Monday, December 30, 2019

The Vector Autoregressive Model Finance Essay - Free Essay Example

Sample details Pages: 7 Words: 2164 Downloads: 7 Date added: 2017/06/26 Category Finance Essay Type Narrative essay Did you like this example? Researches on the causal relationship between equity prices and exchange rates have been conducted with various econometric methods. In this study, I employ the vector autoregressive model and dynamic Granger (1969) causality test to examine the relationship between the variables under study. Empirical studies which are premised on time series data assume that the underlying time series is stationary. Don’t waste time! Our writers will create an original "The Vector Autoregressive Model Finance Essay" essay for you Create order On the contrary, many empirical studies have shown that this assumption is not always true and that a significant number of time series variables are non-stationary (Engle and Granger, 1987). Thus, employing a non-stationary time series data in a regression analysis may result in spurious results (Granger and Newbold (1974)). Therefore, embarking on studies involving time series data necessitates that stationary test is conducted to establish the underlying process of the data series. 3.1 Stationarity Test A data generating process is considered stationary if it has time-invariant first and second moments, and the covariance of two time periods is constant notwithstanding which time periods are used and the distance between them, Gujarati (1995). The process is said to be weakly stationary if the two first conditions are fulfilled but the covariance between two time periods depends on the distance between the time periods, but not on when it is calculated. If the process is stationary around a trend, it is said to be trend-stationary. There are a variety of unit root tests used in the econometric literature principally Augmented Dickey-Fuller (ADF), Dickey-Fuller, Phillip-Perron, Ng-Perron tests, etc to investigate whether the time series data used in a study are stationary or not. I employ the Augmented Dickey-Fuller to examine the stationarity of the variables. 3.1.1 Augmented Dickey-Fuller (ADF) Test The ADF model tests the null hypothesis that there is unit root, against the alternative hypothesis that there is no unit root in the regression. The regression for the ADF test is estimated as follows: (1) where represents the variable that we are examining its properties, is the difference operator, , and are the coefficients to be estimated, p is the chosen lag length, t is the time trend, and t is the white-noise error term. has a stochastic trend under the null hypothesis but under the alternative hypothesis is stationary. Generally, the lag length for conducting the ADF test is unknown but can be estimated using information criteria such as the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) applied to the regressions of the form in equation (1). If the Data Generating Process (DGP) is stationary in the data series at levels, then it will be concluded to be integrated of order zero, I (0). On the contrary, it is not always the case and the un derlying process of the data series may be non-stationary. In effect, the original series need to be transformed into a stationary state by taking difference (d) times. If after taking first difference of the series, it is found that they are all stationary then we can conclude that the DGP is integrated at order one, I (1). Moreover, if the original series used in the study are found out to be integrated of the same order, it is useful to test for cointegration relationship between the integrated variables. 3.2 Cointegration Test It is generally accepted that regression which involves non-stationary time series will lead to spurious results. However, Engle-Granger (1987) proposed that a linear combination of these non-stationary series may be stationary in which case we can say that the series are cointegrated. To compute the Engle-Granger test, let the vector denote the tth observation on N time series, each of which is known to be I (1). If these times series are cointegrated, there exists a vector such that the stochastic process with observation is I (0). However, if they are not cointegrated, there will be no vector with this property, and any linear combination of y1 through yN and a constant will still be I(1). The cointegration regression is estimated as follows: (2) With respect to this regression, it is assumed that all the variables are I (1) and might cointegrate to form a stationary relationship, and thus will result in a stationary residual term. The null hypothesis of non-cointegrati on is that the residual term is non-stationary. Unit root test is conducted on the residuals to find out whether they are stationary or otherwise. To this end, the ADF test is employed to conduct the unit root test. If the residuals are stationary, then one rejects the null hypothesis of non-cointegration. However, if they are non-stationary, then one accepts the null hypothesis of non-cointegration. 3.3 Vector Autoregressive (VAR) Model A vector autoregression is a set of k series of regressions in which the regressors are lagged values of all the k series. The underlying assumption of the model is that all variables are endogenous a priori, and allowance is made for rich dynamics. VAR models offer some level of flexibility and therefore easy to use for analysing multiple time series. This is against the backdrop that one needs not to specify which variables are exogenous or endogenous. However, there are still some difficulties associated with VAR models. In the first place, it is not easy to identify which variables have significant effect on the dependent variable. Also, there is a strict condition that all the data series in the VAR should be stationary. However, most financial time series are non-stationarity. In case the variables are found not to be stationary at levels, then according to Granger (1969), it is more appropriate to estimate VAR or Vector Error Correction Model depending on whether the series are cointegrated or not. The vector error correction model is discussed in the subsequent section. The simplest form of the VAR is the bivariate model. The bivariate model can generally be estimated as follows: (3) where ÃÆ'Æ’Â °Ãƒâ€šÃ‚ Ãƒâ€šÃ‚ ¢it is a white noise term with E (ÃÆ'Æ’Â °Ãƒâ€šÃ‚ Ãƒâ€šÃ‚ ¢it) = 0, E (u1tu2t) =0. 3.4 The Granger Causality Test According to Granger (1969) a variable X could be defined as causal to a time series variable Yif the former helps to improve the forecast of the latter. Thus, X does not Granger-cause Y if Pr (|) = Pr (|) (4) where Pr (.) is the conditional probability, is the information set at time t on past values of Y and is the information set containing values of both Xand Yup to time point t. If the variables are found not to be cointegrated, then the following VAR will be estimated and the Granger causality test is consequently conducted: (5) (6) where SI is the stock price, ER is the exchange rate of the Ghana cedi to the US dollar andare uncorrelated white noise terms, ln represents the natural log, ÃŽ difference operator and t denotes the time period. If the lagged coefficient of vector in equation (5) is significant but that of vector of in equation (6) is not significant then the results imply that there is unidirectional causality from exchange rate to stock price retur ns. However, if the lagged coefficient vector in equation (6) is statistically significant but the lagged coefficient vector in equation (5) is not statistically significant then the results imply that there is unidirectional causality from stock prices returns to exchange rate returns. Moreover, if the lagged coefficient vectors of both equations (5 and 6) are statistically significant then the results imply that there is a bidirectional causality from the stock returns and exchange rate returns. Finally, if both lagged coefficient vectors are statistically insignificant, then this implies that there is no causality between these variables. 3.5 Vector Error Correction Model (VECM) According to Engle and Granger (1987), the VECM is a preferable model to the VAR in equations (5 and 6) if it is found that there is cointegration relation between and or among the data series. The VECM discriminates between both the dynamic short-run and long-run Granger causality. The VECM equations are written as follows: where SI is the stock price, ER is the exchange rate, is the error correction term lagged one period; and are uncorrelated white noise terms. The error correction term () is derived from the long-run cointegration relationship between the variables. The estimates of the error correction term of () also shows how much of the deviation from the equilibrium state is corrected in each short period. To find out the presence of long-run causality between the two data series, one will test for the significance of the coefficient of the error correction term in equations (7 and 8) by employing the t-test. Finally the Wald or F-statistic is used to test for the joint significance of both the error correction term and the various interactive terms in equations (7 and 8). If the lagged coefficient vector of equation (7) is statistically significant but the lagged coefficient vector in equation (8) is not significant then the results imply that there is a unidirectional causality from exchange rate to stock price returns. However, if the lagged coefficient vector in equation (8) is statistically significant but the lagged coefficient vector in equation (7) is not statistically significant then the results imply that there is a unidirectional causality from stock prices returns to exchange rate returns. Moreover, if the lagged coefficient vectors of both equations (7 and 8) are statistically significant then the results imply that there is a bidirectional causality from the stock returns and exchange rate returns. Finally, if both lagged coefficient vectors are statistically insignificant, then this implies that there is no causality between the se variables. 3.6 Lag Length selection Criteria To estimate the VAR/VECM model requires choosing the lag length that reduces the information loss. Thus, choosing the lag length involves neutralizing the trade-off between adding more lags against the marginal benefit of additional estimation uncertainty. Thus, too many lags included in the model will lead to additional estimation errors and whiles too few lags may leave out potentially valuable information. To contain this problem, there are so many models to use to select the lag order, namely the Akaike Information (AIC) and Bayes Information Criteria (BIC). I use the BIC to determine the lag order to the estimate model and therefore I will discuss it briefly. The BIC and AIC are expressed as follows: (9) (10) where SSR(p) is the sum of squared residuals of the estimated AR(p). The BIC estimator of , is the value that minimizes BIC(p) out of the range of lags available. The SSR decreases as more lags are introduced, however the second term increases as more lags are introduced. Moreover, the amount of penalty in the second term of the AIC is relatively smaller to that of the BIC. Thus, the BIC awards more penalty factor relative to the AIC. This implies that BIC gives a consistent estimate of the true lag length unlike the BIC. This makes the BIC preferable to AIC which tends to overestimate the lag order with positive probability. Thus, the second term of the AIC is smaller compared to the BIC. 3.7 Test for Structural Breaks To test for structural breaks in the regression coefficients, I estimate an autoregressive distributed lag (ADL) with dummy variables to represent the periods before and after the redenomination of the cedi. Moreover, to choose the appropriate lag length for both the dependent and independent variables to include in the ADL, I estimate the regression equations with different lag lengths and compare the resulting BICs. In effect, the lag length that resulted in the lowest BIC is chosen to estimate the ADL and then the structural break test is conducted. The ADL is estimated as below: where SIt = stock price returns ERt = exchange rate returns Dt = Dummy variable where Dt = 1 if t à ¢ÃƒÆ' ¢Ãƒ ¢Ã¢â‚¬Å¡Ã‚ ¬Ã‚ °Ãƒâ€šÃ‚ ¥ 3 July, 2007; Dt = 0 if t à ¢ÃƒÆ' ¢Ãƒ ¢Ã¢â‚¬Å¡Ã‚ ¬Ã‚ °Ãƒâ€šÃ‚ ¤ 3 July, 2007 à ¢ÃƒÆ'†¹Ãƒ ¢Ã¢â€š ¬Ã‚  ÃƒÆ' ¢Ãƒ ¢Ã¢â‚¬Å¡Ã‚ ¬Ãƒâ€šÃ‚   = difference operator T = time period; d, are the coefficients of the parameters Chow (1960) model test s for structural break in which case the break dates must be known a priori and the decision is made on the F-statistic that tests the null hypothesis of no break; against the alternate hypothesis that at least one of d is nonzero. Thus, in case of the Chow (1960) test, the investigator has to pick an arbitrary break date or pick a known date based on the feature of the data series. In effect, the results can be highly sensitive to these arbitrary choices and as the true break date can be missed. However, in this study, the break date is identified by the redenomination of the cedi. 3.8 The CUSUM of Squares Test In an attempt to test for the constancy of the variance, I employ the CUSUM of square test Brown et al. (1975). This test is principally based on the square of the residuals on the plot of the quantities. This test involves drawing a pair of critical lines on the diagram which is parallel to the mean value line so that the probability that the sample path crosses one or both critical lines is the significance level. If the sample path stays between the pair of critical lines without crossing any of the two lines, then one can conclude that the variance is constant over the period. However, movement outside of the critical lines implies parameter or variance instability. The CUSUM of squares test is based on the test statistic: (12) where the mean value of is given by: . (13)

Sunday, December 22, 2019

Descriptive Essay - Original Writing - 914 Words

Dreamy I thought. Standing on the corner is a young guy with a smile. I see him here almost every day, so I linger for a while. He tells me his name, and I tell him mine. I m Ester, what s your name? I enquired. My names David .,He replied. We end up talking for a while and I asked him if he had ever left this city. He tells me of all these stories of the places where he s been, the distant lakes and mountains, and in valleys oh so green. I can see it in his eyes, he really has been there, travelled in those distant lands, seen sights beyond compare. I am so honoured just to get to know him, and hear him tell his tales. He makes me laugh and smile, stuff I have never been able to do. I want to go and see the world through†¦show more content†¦I m sure it is because my hearts racing quicker than a train or because my hands are sweatier that the pacific ocean. I felt like a jigsaw puzzle in my heart was complete, but whether this is good or bad I do not know, but honestly , I don t care, I was off to find me and who I think is him, off to find our souls waiting for us to find them. All of a sudden, I saw a dark figure in front of me for about five seconds, but it quickly vanished. I told David but, he didn t believe me and thought I was seeing things. I saw it again, but this time it had increased to twice it is size. My eyes flicker back and forth. Every slight movement or wind caused me to jump. My hand unconsciously clenched into a tight fist. I started to uncontrollably breathe heavily. My mouth was dry and I was unable to swallow. I couldn t make out whether it was a person, animal or shadow. I was so confused and when the figure started to come closer, I was about to scream, but just before I could, he held my mouth and whispered to me, I m here and as long as I am here, you are safe. I took a deep breath and stayed quiet and still. My heart was racing. It was coming closer to me inch by inch. Closer and closer. David, I m scared . He turned me around, pulled my shirt s sleeve up and took something sharp out of his pocket. He held the sharp object up and then slashed it through the middle of my

Saturday, December 14, 2019

Recrystallization of Benzoic Acid Free Essays

Recrystallization of Benzoic acid Chemistry 204-002 Date: 4/9/2011 Hector Ortega Recrystallization is a method used to purify compounds, and this is a very important procedure because compounds are naturally impure. Polarity and solubility play a big role in this experiment and these characteristics are exploited in order to have a crystallization of the desired compound. In this experimented benzoic acid was crystallize using ethanol and water. We will write a custom essay sample on Recrystallization of Benzoic Acid or any similar topic only for you Order Now I chose these solvents based on part C of the experiment (table 1. 1). The compound is too soluble in ethanol but too insoluble in water. Benzoic acid is a polar compound in comparison with ethanol which is a less polar compound. However at low temperatures benzoic acid is insoluble in water. Compounds are soluble in solvents with the same polarity, like dissolves like. Table 1. 1 Benzoic Acid solubility Dissolve Heat Ice H2O No No No Ethanol Yes Yes Yes Hexane No No Acetone Yes Yes Toluene No Yes No The benzoic Acid was dissolved in a very small amount of hot ethanol once dissolved water was added drop wise using a disposable pipet until it got cloudy. Once it reached this point the substance was removed from the steam bed and let cool down at room temperature. It is important to let this cool down slowly so impurities don’t get trapped in between the crystals. After 20 minutes the crystals were filtered out using a vacuum filter method. The crystals were carefully removed from the filter paper and weighted. These crystals were dried out for a period of 2 weeks, to later get a melting point. The MSDS value was compared with the experimental value to verify purity of the crystals Page | 1 Recrystallization of Benzoic acid Chemistry 204-002 Date: 4/9/2011 Hector Ortega Data Collected: Ethanol and Water used as solvents Benzoic acid Grams Started 0. 154 Recovered 0. 126 Final Recovered 0. 064 Percent Recovery 81. 81% *Before Drying for two weeks Final Recovery 41. 52% Melting Point 118. 9 ° C – 119. 9 ° C MSDS MP 122. 4 ° C Percent difference 3. 684% Crystallizing benzoic acid using a mixture of solvents is the most efficient procedure compared to using one solvent alone. By comparing the experimental and MSDS melting points we can see that our recovered crystals had very little impurities only a 3. 8 % difference. If I was to repeat the experiment I would improve the recovery process by letting the substance cool down even more slowly to avoid impurities to get trapped in the crystals. When the crystals were moved from the filter paper to the weighing boat some of the crystals were lost. This could be improved by letting the sample dry longer so the crystals would not stick to the filter p aper or the spatula. Another possible error could have happened when taking the melting point, the rate at which the temperature was rising was a little too high. In the future slowly and gradually rising the temperature would give better more accurate results. Page | 2 Recrystallization of Benzoic acid Chemistry 204-002 Date: 4/9/2011 Hector Ortega 3D embedded Structures  « Che m 3 D E m b e d  » Benzoic Acid  « Che m 3 D E m b e d  » Water Page | 3 Recrystallization of Benzoic acid Chemistry 204-002 Date: 4/9/2011 Hector Ortega  « Che m 3 D E m b e d  » Ethanol References Zubrick (8th ed. ) Chs. 6, 11 and 13 Chemdraw Ultra Version 12. 0 Page | 4 How to cite Recrystallization of Benzoic Acid, Essay examples Recrystallization of Benzoic Acid Free Essays The objective of this experiment was to observe multi-step purification of benzoic acid after performing the extraction from a mixture containing benzoic acid, cellulose, and methyl orange. Recrystallization was done to remove impurities from the sample. The amount of BA recovered during recrystallization is much less than the extracted amount of BA. We will write a custom essay sample on Recrystallization of Benzoic Acid or any similar topic only for you Order Now The difference between the pure and impure samples was observed by comparison of melting points. It was found that impure samples will have a lower and wider melting point range.The experiment performed was important because it provides important knowledge about the chemical nature and reactivity’s of various compounds that can be used in everyday life. Introduction Now that the desired compound is extracted, it still contains impurities. These impurities can be removed through a process called recrystallization. Recrystallization is a method for purifying solid compounds which are frequently the products of organic reactions. This theory is based on three important concepts. The first is that a compound is always more soluble in hot solvents than in cold solvents.Secondly, molecules have unique solubility properties. Lastly, a growing crystal will only accept similar entities into its lattice. This is related to the crystal lattice theory which states crystal formation is anti-entropic based on the equation ? G =? H-T? S. There are three stages of solubility: collision, dissociation, and solvation. In order to raise the probability of collision between the solute and solvent, heat is added to the system. When this occurs, the solute will attack the crystalline structure of the solute and start dissociation. As dissociation continues until all the molecules are free, solvation occurs.Choosing the right solvent is important when considering recrystallization. The solute must have a high temperature coefficient in the solvent: it must be soluble at high temperatures and insoluble at low temperatures, satisfying the first principle stated above. Also the boiling point of the solvent must be lower than the melting point of the solute. This will ensure that the solute dissolves in the solvent and does not melt. The solvent must also be inert to prevent chemical interactions with the solute. Impurities must either be readily dissolved in the solvent or be insoluble.The solvent must also be volatile, and finally, it would be beneficial to the experimenter if the solvent is relatively inexpensive. Once the color and most impurities are removed, the crystals can be formed in the solution through a process called nucleation. Nucleation can be induced by slowly cooling the solution to room temperature. It is important to do this slowly so that small solute resembling impurities do not enter the crystal lattice, as described by the third principle of recrystallization. Chemists often add already pure crystals of the solute to the solution in order to provide a pre-formed lattice for other molecules to enter. This is called seeding. Scratching the glass container in which the solution is contained with a glass stir rod will also induce nucleation on microscopic glass particles. The concept of scratching is similar to that of seeding. Finally, nucleation can be induced by cooling the solution farther in an ice bath; however, this is only a last resort option due to its least efficiency to bring forth crystals. The crystallized solute can then be collected by vacuum filtration. There is a difference observed in the physical properties of the pure compound and the impure mixture. One of the tests of purity is melting point. Melting point is an intrinsic, or intensive, property; the value is independent of the quantity of the substance. Melting point is the temperature at which a substance changes physical state from solid to liquid. Because the substance will have a certain shape and surface area exposure, there will be a time interval in which the melting occurs. Thus, it is more accurate to refer to this as melting range. Melting range encompasses the temperature at which the first particles can be seen turning from solid to liquid until all the sample is in the liquid state. Purer samples have smaller melting ranges.Perfectly pure compounds will have ranges of only 1-2 °C. Impurities lower melting point below literature values and also widen the range between which melting occurs. New techniques and equipment used were used during both parts of the purification process. Activated charcoal was used to adsorb impure colored products. Gravity filtration was used to remove insoluble products which were impurities. Fluted filter paper was used to catch more of the impurities. A heating mantel was introduced during recrystallization. It is a heat source used for solutions. For determining the melting point of benzoic acid, a Mel-Temp apparatus was use.It is used for determining when a small amount of a solid begins to melt and when the melting ends while recording the temperatures, respectively. Experimental: Recrystallization Lab: Initially, took a small amount of impure BA to the side for following week’s lab. The impure BA crystals were weighed, using an analytical balance, and then placed in a 250 mL Erlenmeyer flask. 200 mL of water was boiled (with boiling stones) in a 250 mL round bottom flask using a heating mantel. The boiled water was added slowly to the benzoic acid crystals. Only enough water was added to dissolve the BA crystals. For the rest of the lab the Erlenmeyer flask was kept on a steam bath. Charcoal was added to the BA solution and then gravity filtered using a funnel with fluted filter paper. The filtrate was collected in a 250 mL Erlenmeyer flask. If color in the BA solution still remained then charcoal should be added again. The BA solution was removed from the steam bath and cooled, preferably on a window sill. If crystals did not form while cooling on window sill, use another method to induce nucleation to the start the formation of crystals. The crystals were collects by vacuum filtration and placed on a watch glass to dry. Melting Point of Benzoic Acid: A melting point tube was loaded with BA crystals by inverting the tube into the BA crystals on the watch glass. The tube was packed by dropping through a funnel. The Mel-Temp apparatus was used to determine the melting point range. A rapid melting range experiment was done first and then a slow melting range experiment was carried out to get a better range. Results: Recrystallization lab: Observations: Not much charcoal was used to adsorb the colored molecules The BA crystals were small, shiny, flaky, and white. Almost comparable to texture of dandruff. Data: Mass of extracted Benzoic Acid = 2. 3 g Mass of recrystallized Benzoic Acid = 1. 84 g Calculations: Percent (%) recovery =(weight after recrystalization)/(mass crude BA) ? 100 Percent (%) recovery =(1. 84 g)/(2. 43 g) ? 100=75. 72% Melting Point lab: Observations: Once the benzoic acid began to melt, it happened very quickly.It was hard was difficult to watch the melting and recording the start and end temperature. The crude BA had a lower and wider melting point range. Data: Melting Point Ranges RunCrude (Impure) Benzoic Acid ( °C)Purified Benzoic Acid ( °C) Fast 110. 2-118. 4 at 4. 5 selectivity (Range: 8. 2)115. 4-118. 5 at 4 selectivity(Range: 3. ) Slow113. 2-117. 3 selectivity (Range:4. 1)117. 5-120. 0 selectivity (Range: 2. 5) Discussion ; The goal of recrystallization and determining melting point labs were to explore the techniques used to obtain pure samples from desired compounds. After the extraction the goal was to recrystallize the benzoic acid and determine the percent recovery. Then the goal was to determine the melting point range of the recrystallized benzoic acid and compare it to the melting range of the small sample of the impure benzoic acid. 1. 84 grams of pure benzoic acid was obtained, which was calculated to be 75. 2% from the 2. 43 grams of impure benzoic acid.The percent recovery from the impure sample shows that about three fourths of the sample was able to be collected as pure benzoic acid, and that 0. 59 g of the impure benzoic acid was impurities. From this the experimenter can infer that the pure benzoic acid accounted for most of the mass or that little benzoic acid was lost with the removal of the impurities. Also, there is always a chance that some of the benzoic acid may have remained in the solution instead of crystallizing. Also, using an ice-bath to induce nucleation could have lowered my results or recrystallization because it was the last resort to crystalize the solute. Maybe adding too much charcoal could have adsorbed some of the solute. The charcoal was used to adsorb any of the cellulose (which is the reason for the color) that was left behind. Not too much charcoal was actually used; however, my benzoic acid solution did not have much color so charcoal may not have been needed. Note that the initial value for percent recovery is slightly less than the extracted mass because of the impure benzoic acid set aside for the melting point comparison. The total composition from the very first starting benzoic acid mixture is only 44. 2% (1. 84 grams / 4. 17 grams). Considering practical purposes of recrystallization, one comes to realize how important it is to make this processes as efficient as possible to save money and gain as much product as possible, for example with ibuprofen purification for the pharmaceutical industry. The purity of the sample is shown by the melting range. As expected, the pure benzoic acid had the smallest melting point range of 2. 5 °C. From this, one can tell that this sample was not perfectly pure because pure compounds have melting point ranges of less than 1 °C.There may have been some impurities left in the sample since activated charcoal was not used for this sample. Human error while scraping the impure mixture from the funnel and also from the Erlenmeyer flask would result in a decreased yield. Also, the nucleation may have had some impurity particles collect in the lattice when recrystallizing. After performing the rapid and slow experiment, the temperatures (especially for the pure BA) were not similar. This was probably due to what is called thermometer lag. If the Mel-Temp apparatus’ selectivity was higher than the temperature readings were not as accurate as the slow experiment.The actual value for the melting range coincides with the literature value of 122. 4 °C given in the reagent table. The impure sample, however, had a significantly larger melting range of 4. 1 °C. Also, the impure sample had a lower temperature. This is because impurities disrupt lattice forces and decrease the energy required to break the intermolecular bonds between benzoic acid molecules. One way that this experiment could have been improved is to have more space to perform the various steps in the lab. A lot of the mistakes and errors committed (i. e. pillage) were due to crowding of various equipment that were closely packed next to each other. Overall, theses labs were a success be the experimenter was able to achieve the goals of each lab. The benzoic acid was able to recrystallize and the melting point was fairly close to the literature value even with possible errors performed in lab. Works Cited Wikipedia: The Free Encyclopedia. Wikimedia Foundation, Inc. 22 July 2004. Thurs. 7 Oct. 2010. Zubrick, James. The Organic Chem Lab Survival Manual. 6th. Pittsburgh: John Wiley Son, Inc. , 2008. Print. How to cite Recrystallization of Benzoic Acid, Papers Recrystallization of Benzoic Acid Free Essays Recrystallization of Benzoic Acid Objective To purify benzoic acid by recrystallization and gain experience with a basic organic laboratory techniques. Background Products of chemical reactions are often contaminated with impurities. One method for purifying chemicals, recrystallization, takes advantage of the differences in the solubilities of the desired products and the impurities and the tendency for the slow formation of crystals to exclude impurities from the crystalline solid. We will write a custom essay sample on Recrystallization of Benzoic Acid or any similar topic only for you Order Now HC HC HC CH C CH MgBr + CO2 + HCl HC HC HC CH C CH CO2H ClMgBr Benzoic acid, the chemical that we will be purifying, can be made by reacting phenylmagnesium bromide with carbon dioxide. When the product of that reaction is treated with hydrochloric acid, benzoic acid is formed. From the balanced chemical equation, it is clear that the benzoic acid will not be pure since the byproduct MgClBr, an ionic solid, forms at the same time the desired product forms. Benzoic acid can be separated from ionic solids because the materials have different solubilities in water. At room temperature, benzoic acid is not particularly soluble in water, whereas ionic solids like MgClBr are. Thus, adding water to the crude reaction products will dissolve the ionic solid, and nearly all of the benzoic acid will remain undissolved. If the suspension were filtered, much of the impurity would be washed away; however, the resulting product wouldn’t be as pure as a recrystallized product. To take advantage of the extra purity garnered by crystallization, all of the benzoic acid must be dissolved. On the other hand, the benzoic acid needs to come back out of solution to crystallize. Simply adding room-temperature water cannot accomplish this goal; once the benzoic acid is dissolved there would be no reason for it crystallize. Since benzoic acid is much more soluble in hot water as compared to cold, small amounts of hot water are added to dissolve the benzoic acid. If the hot, saturated, aqueous solution of benzoic acid is cooled, the solution becomes supersaturated, and the supersaturated solution crystallizes. Procedure 1. Obtain a sample of copper(II) sulfate contaminated benzoic acid. 2. Add approximately 0. g (record the actual mass) of the contaminated benzoic acid and 5 mL of water to a 25-mL Erlenmeyer flask. 3. Warm the flask and its contents on a hot plate and slowly add near-boiling water to dissolve the solids. 4. Continue to warm the flask and add near-boiling water until all of the solids have disolved 5. Remove the flask from the hot plate and allow it to cool slowly on the bench top. Covering the flask with a beaker can help slow the rate at which the solution cools. After approximately twenty minutes, crystals will have formed. Cool the suspension further using an ice bath. If crystals have not formed after 20 minutes, there are a few techniques that can be used to coax the crystals out of solution. Often scratching the glass container with a glass rod will induce crystallization. Alternatively, a seed crystal can be obtained by evaporating a drop of the solution on the tip of a stirring rod or spatula. Returning this seed crystal to the super saturated solution will cause crystals to form. 6. Transfer the crystals to a Hirsch funnel, and filter the benzoic acid–water suspension. . Wash the benzoic acid crystals with ice-cold water by pouring ice-cold water over the crystals. 8. Dry the crystals on the Hirsch funnel; that is, allow the vacuum filtration system to draw air through the crystals until the mass of the crystals remains relatively constant. Place the benzoic acid in your drawer and allow it to dry completely. 9. While the benzoic acid is drying, evaporate the water from the aqueous CuSO4 s olution. Remember to add a magnetic stir bar to your flask to lower the risk of spattering. 10. Note the appearance of your CuSO4, and, if possible, record the mass of the CuSO4 that you obtained. 11. After allowing the benzoic acid crystals to dry for a week, determine the mass and the melting point of the benzoic acid. Experimental Report Write an â€Å"experimental† describing the procedure that you followed to recrystallize the benzoic acid. A first draft of the experimental is due one week after steps 1–10 have been completed. A final copy that includes the final mass and the melting point of the benzoic acid is due one week after step 11 is completed. How to cite Recrystallization of Benzoic Acid, Papers

Friday, December 6, 2019

Heart Of Darkness (3810 words) Essay Example For Students

Heart Of Darkness (3810 words) Essay Heart of DarknessHeart of DarknessConrads novel, Heart of Darkness, relieson the historical period of imperialism in order to describe its protagonist,Charlie Marlow, and his struggle. Marlows catharsis in the novel, as hegoes to the Congo, rests on how he visualizes the effects of imperialism. This paper will analyze Marlows change, as caused by his exposure tothe imperialistic nature of the historical period in which he lived. Marlow is asked by the company, the organizationfor whom he works, to travel to the Congo river and report back to themabout Mr. Kurtz, a top notch officer of theirs. When he sets sail, he doesntknow what to expect. When his journey is completed, this little tripwill have changed Marlow forever!Heart of Darkness is a story of one mansjourney through the African Congo and the enlightenment of his soul. It begins withCharlie Marlow, along with a few of his comrades, cruisingaboard the Nellie, a traditional sailboat. On the boat, Marlow begins totell of his experiences in the Congo. Conrad uses Marlow to reveal allthe personal thoughts and emotions that he wants to portray while Marlowgoes on this voyage of a lifetime. Marlow begins his voyage as an ordinaryEnglish sailor who is traveling to the African Congo on a business trip. He is an Englishmen through and through. Hes never been exposed to anyalternative form of culture, similar to the one he will encounter in Africa,and he has no idea about the drastically different culture that existsout there. Throughout the book, Conrad, via Marlowsobservations, reveals to the reader the naive mentality shared by everyEuropean. Marlow as well, shares this naivete in the beginning ofhis voyage. However, after his first few moments in the Congo, he realizesthe ignorance he and all his comrades possess. We first recognize the generalnaivete of the Europeans when Marlows aunt is seeing him for thelast time before he embarks on his journey. Marlows aunt is under theassumption that the voyage is a mission to wean those ignorant millionsfrom their horrid ways(18-19). In reality, however, the Europeans arethere in the name of imperialism and their sole objective is to earn asubstantial profit by collecting all the ivory in Africa. Another manifestation of the Europeansobliviousness towards reality is seen when Marlow is recounting his adventureaboard the Nellie. He addresses his comrades who are on board saying:When you have to attend to things of thatsort, to the mere incidents of the surface, the reality-the reality I tellyoufades. The inner truth is hidden luckily, luckily. But I felt itall the same; I felt often its mysterious stillness watching over me atmy monkey tricks, just as it watches you fellows performing on your respectivetight ropes forwhat is it? half a crown a tumble(56).What Marlow is saying is that while heis in the Congo, although he has to concentrate on the petty little everydaythings, such as overseeing the repair of his boat, he is still aware ofwhat is going on around him and of the horrible reality in which he isin the midst of. On the other hand, his friends on the boat simply dontknow of these realities. It is their ignorance, as well as their innocencewhich provokes them to say Try to be civil, Marlow(57). Not only are they oblivious to the realitywhich Marlow is exposed to, but their naivete is so great, theycant even comprehend a place where this so called reality would evenbe a bad dream! Hence, their response is clearly rebuking the words ofa savage for having said something so ridiculous and uncivilized. Quite surprisingly, this mentality doesnot pertain exclusively to the Englishmen in Europe. At one point duringMarlows voyage down the Congo, his boat hits an enormous patch of fog. At that very instant, a very loud cry is let out(66). After Marlow looksaround and makes sure everything is all right, he observes the contrastsof the whites and the blacks expressions. It was very curious to see the contrastof expression of the white men and of the black fellows of our crew, whowere as much strangers to this part of the river as we, though their homeswere only eight hundred miles away. The whites, of course greatly discomposed,had besides a curious look of being painfully shocked by such an outrageousrow. The others had an alert, naturally interested expression; but theirfaces were essentially quiet. . . (67). Once again, we see the simple-mindednessof the Europeans, even if they were exposed to reality. Their mentalityis engraved in their minds and is so impliable, that even the environmentof the Congo cant sway their belief that people simply dont do the horriblethings Marlow recounts. The whites are dumbfounded and can not comprehendhow people, in this case the natives, would simply attack these innocentpeople. That would just be wrong! The blacks, however, who are cognizantof the reality in which they live, are essentially quiet. They feel rightat home, and are not phased by the shriek. Similarly, the difference of mentalitiesis shown when Marlow speaks of the portion of his crew who are cannibals. While in themidst of his journey, Marlow, quite casually, converses withthese cannibals; even about their animalistic ways! As Jacques Berthoudsaid so accurately in his Joseph Conrad, what would be nspeakable horrorin Londonbecomes, on the Congo river, an unremarkable topic of conversation(47). These unspeakable horrors are hardly unspeakable in the Congo becausethey are normal occurrences there. On the Nellie, Marlow explains to his comrades,the basic difference between living in Europe, and being in the Congo. He states:You cant understand. How could you? Withsolid pavement under your feet, surrounded by kind neighbors ready to cheeryouor to fall you, stepping delicately between the butcher and the policeman,in the holy terror of scandal and gallows and lunatic asylumshow canyou imagine what particular region of the first ages a mans untrammeledfeet may take him into by the way of solitudeutter solitude withouta policemanby the way of silence utter silence, where no warning voiceof a kind neighbor can be heard whispering of public opinion(82)?In Europe, there are kind neighbors whoare there to make sure that everything is all right. The European liveshis life stepping delicately between the butcher and the policeman. Everywherehe looks, there is always someone there who can catch him if he is falling. On the other hand, once a man enters the Congo, he is all alone. No policeman,no warning voice of a kind neighborno one!It is now when Marlow enters the Congoand begins his voyage, that he realizes the environment he comes from isnot reality, and the only way he is going to discover reality is to keepgoing up the river There is one specific theme in Heart ofDarkness in which the reader can follow Marlows evolution from the everydayEuropean to a man who realizes his own naivete and finally to hisuncovering of his own reality. This evolution comes about as a direct resultof Marlows observations of how things are named. This sounds very unusual,that a man would find his true reality by observing the names of certainthings. However, it is precisely these observations which change Marlowforever. Marlow first realizes the Europeans flaw of not being able togive something a name of significance, in the beginning of his voyage,when he has not quite reached the Congo, but he is extremely close. Once, I remember, we came upon a man ofwar anchored off the coast. There wasnt even a shed there, and she wasshelling the bush. It appears the French had one of their wars going onthere-abouts. Her ensign dropped like a limp rag; the muzzles of the longsix inch guns stuck out all over the low hull; the greasy, slimy swellswung her up lazily and let her down, swaying her thin masts. In the emptyimmensity of earth, sky, and water, there she was, incomprehensible, firinginto a continent. Pop, would go one of the six inch guns; a small flamewould dart and vanish, a little white smoke would disappear, a tiny projectilewould give a feeble screechand nothing happened. Nothing could happen. The Career that interest me is being a doctor. EssayNo; you want a deliberate belief. An appeal to me in this fiendish rowisthere? Very well; I hear; I admit, but have a voice too, and for good orevil mine is the voice that can not be silenced (60).This is the lesson which Marlow has learned. Objective standards alone will not lead one to recognize the reality insomething. One can not only depend on anthers principles to find his realityin something because they have not had to bear the pain and responsibilityof creating it. Principles are usually acquisitions, which like other thingswe acquire rather than generate, like clothes are easily shaken off. Thepower of speech which will sustain a man is the power to create or affirmfor ones self a deliberate, or a chosen belief (Bruce Johnson. 79). This judgment must be from ones own internalstrengths. That is why Marlow says, for good or evil, mine is the speechthat can not be silenced. As Kurtz has taught him with his own judgment,a judgment of truth overpowers morality. To find ones own reality, onemust not rely solely on other peoples morality, others peoples principlesand he must assess his own life. What Kurtz did is that he showed thatregardless of whether the truth is good or bad, one must face up to hisreality. He must face up to his own actions even when the conclusion isthe horror, and by doing so, he will find his true reality. Marlow understands that being true to yourselfis not following anthers moral code, but being able to judge ones selfhonestly and uncover their own reality. It is because of this understandingthat Marlow claims that Kurtzs last words is a moral victory paid forby innumerable defeats(120). Despite Kurtzs immoral ways, he is victoriousbecause he didnt run away from the truth; and that is his moral victory. He is true to himself.!On his voyage, Marlow notices at one ofthe stations, a picture that Kurtz had drawn when he was there. It is asketch in oils on a panel representing a woman draped and blindfolded,carrying a lighted torch. The background was sombrealmost black(40). At the time, Marlow didnt really know what it meant. However, this isa precise representation of Kurtz himself. Firstly, the background wassombrealmost black. This is a manifestation of Kurtz because his lifeis full of darkness. He kills, he steals, and he is worshipped as a god. Kurtz cannot be without blackness and survive. In addition, the picturedisplays the lesson itself. It is a picture of the lady of justice holdinga torch. This is Kurtzs role. Unlike Europe, which imposes their principlesupon others, he is merely there to illuminate(79). Kurtz is there toexpand the peoples minds, to introduce them to a broad new spectrum ofreality. However, he does not impose his own reality upon them. Hence,he is blindfolded in the picture. To him, they make a subjective decisionand they find their own truth, regardless of what that truth may be. Thatis his lesson. Eventually Marlow realizes that Kurtzspicture was in essence, a self portrait. The same thing which Kurtz conveyedwith the horror, he conveyed with this picture. Marlows realizationis evident with this remark. I dont like workno man doesbut I likewhats in the workthe chance to find yourself. Your own realityforyourself, not for others(47). Marlow learns the essence of naming andunderstands what it means to be yourself. However, Marlow has encounteredtwo extremes. The European mentality, which is completely oblivious toreality, and Kurtz, a man who has found his reality, but it is one of horrorand no restraint from any wrongdoing. He is now returning to his home todeal with his former world, however, he now possesses his new understanding. Marlow cannot return to his previous European ways simply because hehas been enlightened and lost his naivete. However, why cant he adapt Kurtzs waysand live the other extreme? At one point, Marlow had peeped over the edge(119). Why didnt he jump over? Marlow is repelled from joining Kurtz for severalreasons. Firstly, Kurtz had kicked himself loose from the earthhe hadkicked the earth to pieces. He was alone, and I before him didnot know whether I stood on the ground or floated in the air(112). Kurtzhad denied any sort of moral convictions in order to be worshipped as agod. Because of this unmonitered power, Kurtz lost all sense of restraintand became the savage that he was. Marlow, however, has not lost his senseof morality. What Marlow rejected in Kurtz was the complete absence inKurtz of any innate or transcendental sanctions (Johnson. 99). It is because of Marlows rejection ofboth the Europeans, who Marlow claims are full of stupid importance,and of Kurtzsinability to establish his own moral code, that Marlow choosesan alternative reality(Berthoud. 60). The first time the reader witnessesMarlows choice and becomes a centrist, is when he first gets back to Europe. Marlow finds himself resenting the way the Europeans went about their life,hurrying through the streets to filch a little money from each other(120).Notonly did he find their lives meaningless, but he mocked them to himself. I had no particular desire to enlighten them, but I had some difficultyrestraining myself from laughing in their faces so full of stupid importance I tottered about the streetsgrinning bitterly at perfectly respectablepeople. I admit my behavior was inexcusable (120). Although Marlowlooked down upon these Europeans, he says something remarkable. He judgedhis own actions and found them inexcusable. This is his manifestationof breaking away from Kurtzs extreme. Unlike Kurtz who lacked all restraintand would never find looking down on people bad, Marlow realized that hecouldnt hold it against them simply because they didnt know better. Clearly,Marlow is edging toward a middle ground. Despite this act of judgment, the readerdoesnt know exactly where Marlow stands. However, Marlow does somethingthat is the quintessential act of affirmation that he has chose the middleof the two extremes. While aboard the Nellie, Marlow tells his comradesthat I hate, detest, and cant bear a liesimply because it appallsme. There is a taint of death, a flavor ofmortality in lies(44). Towards the end of the novel, Marlow is invitedby Kurtzs fiancee to go to her house to speak of her beloved Kurtz. Uponher asking Marlow what his last words were, Marlow responded The lastword he pronounced wasyour name(131). He lies to her. He does somethinghe utterly detests. This is the event that convinces the reader of Marlowsuptaking of a middle position. He does look inside himself and use hisown personal ability to judge this event. He does what Kurtz had told him. Despite his abhorrence of lies, he judges this situation and decides thatit was right to lie. However, he is different from Kurtz. Kurtz did judgeevery event independently, however, he does it solely based on his ownwhims. He could not incorporate any objective principles whatsoever inmaking his decision. Marlow does judge every event independently, however,he can not rely solely on his own creeds. Regardless of his decision, hewill always incorporate some objective principles into his judgment. Marlownow creates his alternative reality and achieves his truth. When Marlow was exposed to the imperialisticenvironment of the congo, it had a tremendous effect upon him. The protagonistof Conrads novel undergoes a drastic change in response to his environment,common only to that specific time period. Kurtz shows Marlow the flawsin the Europeans imperialistic ideals. Kurtz sees the meaninglessness ofEuropean standards of the time, and therefore changes his entire perceptionand behavior.

Friday, November 29, 2019

Life In Past Essays - American Slaves, Sojourner Truth, Slavery

Life In Past SOJOUNER TRUTH Sojourner Truth was born under the name Isabella Van Wagener. This was not even her last name but her masters last name because slaves went by their master's last name. She had at least five children with another slave that her master married her to named Thomas. For a while she lived in slavery until a day in 1826 when Isaac Van Wagener set her free. In irony less then a year later slavery was banned in New York. Right after slavery had been made illegal she went to court and recovered her smallest son who had been sold away. In 1829 she went to New York City and supported herself with domestic employment. While in New York City she met Elijah Pierson, a religious missionary. She joined his retrenchment society and eventually his household. In 1843 she left New York City and changed her name to Sojourner Truth, which she used from then on. Obeying a voice she said she heard from god travel up and down the land she went to churches all over the place and got people to accept the Bible and God. In 1850 she wrote a book which she named The Narrative of Sojourner Truth. One other thing that Sojourner Truth was famous for was her Ain't I A Women speech in 1851 at the Women's Rights Convention. No formal record of it exists, but Frances Gage who was the president of the convention, recounted Truth's words. She said that the words Ain't I A Women were very strong and uplifting. Also they have become common words women use today to show their rights. In the 1850s she settled in Battle Creek, Michigan. While here she gathered supplies for black volunteer regiments and in 1864 went to Washington D.C., where she helped integrate street cars and was received at the White House by Abraham Lincoln. For the rest of her life she helped fight for freedom of slaves all around the U.S. then in 1875 she returned to Battle Creek, where she stayed until her death. Social Issues Essays

Monday, November 25, 2019

Illegal Immigrants are Taking American Rights essays

Illegal Immigrants are Taking American Rights essays Illegal Immigrants are Taking American Rights According to the U.S. Census Bureau, more than eight million illegal immigrants were living in America in the year 2000. The Migration Policy Institute reported that number increases by five hundred thousand every year. The United States spends over 20 billion dollars a year to support needy illegal immigrants. The fight is on to end illegal immigration. The overcrowded dwellings, strained public services, school congestion, uncollected payroll and property taxes, disregard for and destruction of public and private property, crime and other unbearable living conditions brought on by people and businesses who disregard local ordinances and state and federal laws. By blatantly disregarding these laws, illegal immigrants eliminate benefits such as jobs, schooling, and public services away from deserving legal immigrants and American citizens. As each year goes by, the number of jobs held by illegal immigrants decreases the availability of employment positions for legal U.S. citizens. The employment securities Americans hope for is dwindling at the cost of nothing. As long as illegal aliens are willing to work at inferior wages and distressed working conditions, the wages of American workers are being depressed. Minority workers and those without a high school degree are especially being affected. At the turn of the century, it was estimated that the total number of American workers being displaced was roughly 730,000. $4.8 billion that could be paying the salaries of legal workers is being compromised to pay lower wages for immigrants unwilling to work under the conditions of their own countries. Virginia Abernathy, a professor at Vanderbilt University, says that It is indeed true that there are profits to be made by the importation of millions of low-skilled, low-wage workers into the country, but the profits are f or a few. They are for the employer.2 Therefore, th...

Thursday, November 21, 2019

Doesnt fit her ( wrote it in the other instruction box) Assignment - 1

Doesnt fit her ( wrote it in the other instruction box) - Assignment Example Consequently, the church cannot significantly influence or prevent the state from continuing its policies, statutes, and laws (Stearns, 2011). Likewise, the secularism concept correctly affirms all religions have the same or equal level in society. One religious group should not be above or superior to another religious group. For example, the Buddhism religion should be superior to the Christian religion. Likewise, the Islam religion must not be superior to the Christian religion (Stearns, 2011). Further, James Wood rightfully uses the Atheist example to prove Christianity can be reconciled with secularism. The atheist (secular) questions the theory of the big_bang explosion concept, creating the possibility of Christianity’s creation concept within a secular environment. The explosion concept disavows God’s creating the universe. By questioning the concept of the Big Bang theory, it is like a Democrat Party person questioning whether he or she is truly a Democrat. In another article, James Wood correctly explains the issue of secularism to Gopnik. The discussion focused on current day society (The New Yorker, 2014). Gopnik’s growing up years includes having a secular family. Gopnik grew up in a deeply religious environment. Wood grew up in a Christian family environment. Both Gopnik and Wood accept the Atheism concept. Atheism disavows the presence of a God who created the universe. Both Wood and Gopnik espouse the unbridled democratic exercise of different religious beliefs and the same beliefs’ related experiences, indicating Christianity concepts can thrive well in a secular atheist environment. Furthermore, Christianity rightfully dictates that religious leaders can advice the people on how to act or not act on certain political issues. The Christian religious leaders may lead the people to rally against the passage of certain laws that run against certain religious teachings. Such teachings

Wednesday, November 20, 2019

The Aspects of Pablo Picasso's Life Assignment Example | Topics and Well Written Essays - 500 words

The Aspects of Pablo Picasso's Life - Assignment Example The paper "The Aspects of Pablo Picasso's Life" gives a review of Pablo Picasso's life. It would not be an exaggeration to suggest that every person who is not even distantly connected to art has heard of Pablo Picasso. This paper will explore some of the aspects of his life. A Spanish painter, Pablo Picasso was one of the founders of the movement called Cubism. He was born on 25 October 1881 in Malaga, Spain and died at the age of 91 in Mougins, France. He did not have any physical, mental or emotional problems, exception for excessive passion for women. Speaking of his marriage, one should note that he was married twice: first time to Olga Khokhlova, a Russian ballerina, and second time to Jacqueline Roque. In spite of that fact he also had numerous affairs and children, for example from a seventeen year old girl named Marie-Thà ©rà ¨se Walter. The family of Picassos consisted of a father who was a curator in museum and a mother. Picasso struggled with different things in the cou rse of his life: he had numerous relationships, some of which he had to keep a secret; he opposed to different social as well as religious orders, fighting for his own vision of the world. As for his artistic legacy, one should note the following works: Les Demoiselles d'Avignon, The Weeping Woman and Guernica. They all laid a foundation of different movements which have influence the development of art for the centuries to come. Thus, there were different styles that Picasso used: there was some realism.

Monday, November 18, 2019

Alexander McQueen Savage Beauty Exhibition Research Paper

Alexander McQueen Savage Beauty Exhibition - Research Paper Example The exhibition serves both as a source of education and a source of inspiration for the contemporary fashion designers. In addition to that, the exhibition was also a very informative and entertaining show for the students of Fashion Designing. The exhibition exhibited more than 70 accessories and about 100 ensembles from the prolific career of McQueen from his career ranged over 19 years (â€Å"About the Exhibition†). The audience leaves the show confused because the fashion that reflected from the models’ outfits represented McQueen’s varying states of mind at different points in time. Such exhibitions are hard to watch because of the conflict between the overt expression of such sensitive themes as vulgarity and the cultural conservatism of the audiences. Despite all their absurdity, one thing that adds to their appeal of the clothes displayed in the exhibition is that they have been designed keeping the different kinds of weather and seasons into consideration. For example, there are clothes made in net to be worn during the summer season whereas there is a whole furry range for the winter season. One theme that was commonly observed in all of his outfits was that they were inspired by birds; pigeon , peacock, and hen to name a few. While watching the show, it is hard for the audiences to predict what is coming up next or even how they feel about it. I chose this topic because McQueen’s fashion show stands out from the queue of traditional fashion shows because of a number of reasons. I have personally never found a fashion show so dramatic, appealing, and at the same time, controversial. It was something very unusual so I wanted to share it with others. If I was in charge, one thing that I would like to change is nudity. I would at least cover up all the private parts of the models in respect of our cultural values of modesty and conservatism.  

Saturday, November 16, 2019

Natural Zeolite as a Cost-effective Opacifier

Natural Zeolite as a Cost-effective Opacifier Ali Ghafarinazari1, 2 à ¯Ã‚ Ã¢â‚¬ ºÃƒ ¯Ã¢â€š ¬Ã‚ ªÃƒ ¯Ã‚ Ã‚ , Esfandiar Amiri1, Mahnaz Karbassi3, Morteza Soroor1, Talieh Rajabloo3 Abstract Zircon as an opacifier material is under the very real risk of being replaced. This is mainly because of two reasons: the anticipated shortage of high-quality grade zircon, and high costs associated with the production of zircon as an opacifier material, which is resulting in upward pressure on zircon prices. This study aimed at assessing the influence natural zeolite as opacifier of on both the technological behavior during processing and the technical performances of ceramic glaze for tile manufacturers. Moreover, preliminary investigations show this category of tiles has potential at antibacterial activity in a cost-effective way. Keywords: Glass-ceramic; Anti-bacterial Tile; Titanates; Zirconia; 1. Introduction The ceramic tile industry is being progressively moving its worldwide production toward new materials with improved aesthetic and technical properties. The availability of these raw materials in the huge amounts required by the tile industry is a problem in many areas, while in other contexts it is the high price to make the tile manufacture disadvantaged in competition with other producers of building materials, whose manufacturing costs are lower. Thus, the ceramic industry is continuously searching for cheap raw materials able to replace the traditional without altering the process and product characteristics [1]. In glaze production, amongst commercial frits, zircon (ZrSiO4) is most conventional opacifier [2]. Nevertheless, these frits are quite expensive and therefore, there have recently been certain attempts to lower the production cost such as optimizing amount of zircon [3], or taking another suitable glass–ceramic glaze systems [4]. Another common opacifier is titania (TiO2). Although refractive indices of titania (2.52 for anatase and 2.76 for rutile [5]) is higher than zirconium oxide (2.17 [1]), but it has technical problems. First is low chemical stability during melting. In addition, rutile, which is stable structure of titania in standard conditions, is the main problem. Because rutile phase, in opposite of anatase, is yellow and leads to increase roughness of surface. Zeolites are high porous and crystalline alumino-silicates with a three-dimensional structure based upon repeated units of silica (SiO4) and alumina (AlO4) tetrahedral [6]. Based on high-temperature phase transformations of natural zeolites [7], possibility of using Iranian natural zeolite as opacifier of tiles are investigated in this study. Zeolites belong to the tectosilicate mineral group and are building up by a framework of corner-sharing. The framework arranges as such to form a microporous structure with large cages (diameters less than 2 nm) connected into channels. They possess special properties, such as ion exchange, molecular sieves, a large surface area, and catalytic activity, which make them a preferable material for tremendous industrial applications in industries such as domestic and commercial water purification, softening, petrochemical industry, biogas industry, heating and refrigeration, detergents, medical, agriculture [8]. Now a days, they are promising for im plementation at ceramic production, such as brick [9], ceramic pigments [10], porcelain and tiles bodies [11] also self-glazing ceramic tiles [12]. The main objective of this study is to use Iranian natural zeolite and develop from this a zeolite opacifier product for glazes, which possesses superior opacifying properties or whiteness values after application on a ceramic body, compared to that of the current zircon, more expensive commercial ceramic or prime grade zircon materials. 2. Experimental Procedure 2.1. Fabrication of Samples In the first part of the experimental study, one single fast-firing opaque tile glaze selected as standard frit (Table 1). The basic Standard frit composition was selected consisting of 6 wt% suspending agent (kaolin), 0.2 wt% deflocculated (sodium tri-poly-phosphate), and 0.1 wt% ligand (Carboxyl Methyl Cellulose, CMC) in an eccentric mill used at selected suspension compositions. At this research, all of materials were of commercial grades (less than 98 wt% purity) from industrial clays. 2.2. Sintering The frit suspensions applied on the surface of tile supports using a regulated glaze applicator for the deposition of raw layers with 0.4 mm thickness. The test specimens were then fired in a roller kiln corresponded to the temperature and rate used industrially to manufacture the product with the support and glaze in question. Heating and cooling rates were about 40  ºC/min and soaking time at 1000  ºC was 3 minutes. 2.3. Characterization of samples The opacity of glaze was evaluated based on a colorimetric analysis using a Minolta CM-2600d spectrophotometer. The results are expressed by the tri-chromatic coordinates: L* means the degree of whiteness, a* indicates the variation between green and red colors, and b* presents the variation between blue and yellow colors, therefore investigation of opacity amount of L* is very important. To better understand the gloss results of the glazes (ÃŽ ²60) was determined by Zehntner ZGM1110 glossiness analyzer. To complement the results, the glazes were characterized micro structurally by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). Crystalline phase identification was performed on glazes prepared from ground samples using a X-ray diffractometer (Philips PW 170) operating with (Cu-KÃŽ ± = 1.54056 Ã…, 35 kV, 40 mA) radiation in the range of 10-60 ° 2ÃŽ ¸, using the following settings: 0.1 mm receiving slit, 0.4 s/0.04 ° 2ÃŽ ¸ counting time. FESEM images were taken by Hitachi S-4160. On account of experiments method and results, particularly SEM, we predicted that the new tile has potential for antibacterial activity. The popular method for antibacterial activity is  ½ McFarland. We described in detail this method for antibacterial tile [13]. As briefly speaking, E. coli and S. aureus were deposited on tile slide (5 cm Ãâ€" 5 cm). Each slide was placed in a sterile vial. Tryptone soy broth was then added to each vial. An aliquot (10 ml) of S. aureus or E. coli suspension was added to each vial (1.6 Ãâ€" 103 ml-1) containing the slides. The vials were incubated with agitation at 35  °C, 220 rpm. The bacteriostatic activity was evaluated after 24 h and the percentage of bacteria reduction was calculated using the following equation (1): (1) In which R is the reduction rate, A is the number of bacterial colonies from untreated tiles and B is the number of bacterial colonies from the treated tiles. 3. Results and discussion In order to investigate effect of zeolite in glaze at different chemical conditions, some experiments carried out in the same firing profile. Output of glossiness and spectrophotometer these experiments showed in Table 2. Before going to the results, it is better to remind that depend on type of body, in general acceptable amount of L* for an opaque glaze is 83.24, it is noticed that this reference opaque glaze has 14wt% Zircon. In addition, acceptable amount for glossiness for shiny tile is at least 88 such as standard frit which is perfectly transparent. After checking standard, conventional opacifires, zircon and titania, were added. When 10wt% zircon was added to frit as state of compound, degree of whiteness and covering increased sharply, without significant effect on glossy. Uniformity distribution of unfired zircon powders on standard frit exhibited on Figure 1. Another conventional opacifier, titania, was added in amount of 5 and 10wt% to the standard frit. Outcomes in Table 2 confirm that amounts of whiteness (L*) and covering (a*) is very upper than zircon but yellowish amount (b*) and decreasing of shiny confirm that titania is in rutile crystallographic state. Morphology of titania on glaze is directly depended on crystallographic state. Microstructural studies confirmed that rutile crystals always have had an acicular morphology, however, anatase crystals were observed with cubic and rectangular morphologies [14]. The other stable phase of titanium in glaze is sphene (CaTiSiO5 [15]), which is completely sphere in glaze [4]. Visual effect of sphene and anatase is white, while anatase has benefits such as semiconductor and antibacterial effects. Bou et al. published that in order to improving smoothness and glossiness adding 1-3wt% P2O5, rutile transformed to sphene. The problem of sphene is non-uniform distribution in glass matrix [4], which decrease chemical and mechanical resistant. Based on Figure 2, existence of rutile confirmed. This big crystal leads to roughness of surface and diminishing glossiness to 25. One of interesting results of FESEM of glaze containing titania is elemental distribution on glass-ceramic. In glassy matrix, atomic percentages of fluxes are 0.93, 4.87, 7.01, and 2.36 % for Na, K, Ca, and Zn respectively, but these amounts are 3.46, 5.25, 12.35, and 3.11 %; i.e. around crystalline part flux materials especially sodium and calcium lead to nucleation. And about 3 at% titanium was solved in glass, due to low chemical stability. In order to investigation of effect of natural zeolite in glaze and comparing with other opacifiers, 10wt% natural zeolite supplemented to the standard. Result of XRD shows that the zeolite has crystallinity based on having less amount of background with sharp peaks (Figure 3). The zeolite leads to covering and whitening surface without significant effect on glossy. As it can be seen in Figure 4, there are large amounts of unfired or crystalline materials in glass matrix which is due to existence of zeolite. In contrast, for higher temperature (1100  °C) and time duration (2 h) zeolite acts as a flux [1], but at this condition it acts as a refractory. Although these results (Table 2) were comparable with zircon, we could not achieve a sufficient opaque glaze because of refractive index of zeolite which is about 1.48 – 1.60 [16], and is close to silicate-leadless glasses (1.5 – 1.7) [5]. For sufficient covering with whitening in glaze by zeolite, possibility of using zeolite as a nucleus for titanium oxides was inspected. For this purpose, 3wt% TiO2 and 7wt% zeolite added to the standard. Table 2 confirms that this glaze is an acceptable as an opaque glaze. This glaze has a shiny surface, well covered tile body, high whiteness, and especially low price due to cheap raw materials. To complement the results, FESEM was carried out on these tiles. Figure 5 exhibits rectangular nanoparticles (25-500 nm, 85 nm average) with uniform distribution in glaze. Based on previous lectures, this structure is related to anatase [5]. Owing to EDX analysis, elements distribution on matrix and ceramic generally was the same with previous samples but percentage of Ti in matrix relented to 0.42 (instead of 3 at% in Figure 2). Indeed, natural zeolite is a cheap agent for nucleation of nanocrystalline anatase without side effect on other properties of tiles. One proposed mechanism for this phenomenon from thermodynamic point of view is alumina and silica which leads to stability of anatase [9]. Based upon zeolite is alumino-silica, this reasoning was checked by kaolin, which is a mineral clay contains mainly alumina and silicates. Results of this experiment are illustrated in Table 2 and Figure 6. Kaolin had no effect on phase and morphology of rutile, and it led to increasing of roughness and firing temperature of glaze. In a conclusion ability of natural zeolite in making glass-ceramic by nanoparticles of anatase is unique according to high porosity and crystallinity (Figure 3) structure. Due to the fact that there are anatase nanoparticles in the glaze, it is promising having antibacterial activity [17]. This phenomenon investigated by  ½ McFarland method as wrote in experimental procedure at end of section 2.3. In this case it has been shown achieving stable nanostructural anatase is not enough for antibacterial activity [18]. In fact, anatase must be excited by Ultraviolet illumination. This tile has just about 35% bacteriostatic which is not significant comparison by naked eye and it needs to measure by microscope. This result is very low in comparison with other components which had more than 95% [13]. It would be obvious that titania at glaze initially melted and then solidification carried out in the form of anatase. The increase zeolite anti-bacteria agent is prepared by achieving smaller anatase particles and better distribution which can be realized by chemistry of glass network. However, due to the fact that propose of this research was just opacity, this result also is very interesting and beyond our goal. 4. Conclusion Natural zeolite is a new mineral source for construction and ceramic glass materials. Our research showed that zeolite is economically expedient to use natural zeolite for fabricating opaque glaze. Indeed natural zeolite led to stabilized nano crystalline of anatase. This glaze has potential for antibacterial tiles. Initial investigation showed potential of antibacterial activity if this kind of products in a cost-effective way. References [1] Demirkiran AÃ…Å ¾, R. Artir, and E. Avci. Effect of natural zeolite addition on sintering kinetics of porcelain bodies. Journal of materials processing technology. 2008;203(1-3):465-70. [2] Beals M, et al Study of Particle Size of the Opacifying Phase in Titania Enamels: I, Change of Particle Size with Change of Concentration of Dissolved TiO2. Journal of the American Ceramic Society. 1951;45(1):403. [3] Bish DLaJWC. Thermal behavior of natural zeolites. Reviews in mineralogy and geochemistry. 2001;45(1):403. [4] Bou E, et al. Microstructural study of opaque glazes obtained from frits of the system: SiO2-Al2O3-B2O3-(P2O5)-CaO-K2O-TiO2. Journal of the European Ceramic Society. 2007;27 (2-3):1791-6. [5] Casasola R, J. Rincà ³n, and M. Romero. Glass–ceramic glazes for ceramic tiles: a review. Journal of Materials Science. 2012;47(2):553-82. [6] Eppler R. Crystallization and Phase Transformation in TiO2 Opacified Porcelain Enamels: 11, Cornparison of Theory with Experiment. Journal of the American Ceramic Society. 1969;52(2):94-9. [7] Diop MaMG. Sodium silicate activated clay brick. Bulletin of Engineering Geology and the Environment. 2008;67(4):499-505. [8] Osman Gencel a, Mucahit Sutcu b, Ertugrul Erdogmus c, Vahdettin Koc d, Vedat Veli Cay e,, Gok MS. Properties of bricks with waste ferrochromium slag and zeolite. Journal of Cleaner Production 2013;59 111-9. [9] Hanaor DaC, Sorrell. Review of the anatase to rutile phase transformation. Journal of Materials Science. 2011;46(4):855-74. [10] Pekkan KaBK. Production of opaque frits with low ZrO2 and ZnO contents and their industrial uses for fast single-fired wall tile glazes. Journal of Materials Science. 2009;44(10):2533-40. [11] Pogrebenkov VM, Sedelnikova MB, Vereshchagin VI. Zeolites: Raw material for ceramic pigments. Glass and Ceramics. 1998;55(1-2):55-6. [12] Pogrebenkov VM, E.D. Melnik, and V.I. Vereshchagin,. Use of Siberian mineral raw materials in the manufacture of self-glazing ceramic tile. Glass and Ceramics. 1997;54(11-12):373-5. [13] Ghafarinzari A, Moztarzadeh F, Rabiee SM, Rajabloo T, Mozafari M, Tayebi L. Antibacterial activity of silver photodeposited nepheline thin film coatings. Ceramics International. 2012;38(7):5445-51. [14] Teixeira SaAMB. Development of TiO2 white glazes for ceramic tiles. Dyes and Pigments. 2009;80(3):292-6. [15] Frost BR, K.R. Chamberlain, and J.C. Schumacher, Sphene (titanite): phase relations and role as a geochronometer. Chemical Geology. 2001;172(1–2):131-48. [16] Larlus O, et al. Silicalite-1/polymer films with low-k dielectric constants. Applied Surface Science. 2004;226(1-3):155-60. [17] Saeki Y. Application of Antibacterial and Self-Cleaning Effects to Noncementitious Construction Materials. Applications of Titanium Dioxide Photocatalysis to Construction Materials: Springer; 2011. p. 17-22. [18] Niederhà £usern S, Bondi M, Bondioli F. Selfà ¢Ã¢â€š ¬Ã‚ Cleaning and Antibacteric Ceramic Tile Surface. International Journal of Applied Ceramic Technology. 2012. Figure captures Figure1 FESEM of glaze with 10wt% zircon. Figure2 FESEM of standard frit with a) 5 and b) 10wt% titania Figure3. XRD from Iranian natural zeolite Figure4. FESEM of standard frit containing 10wt% natural zeolite Figure5. FESEM of standard frit containing 3wt% TiO2 and 7wt% Zeolite; a) morphology of crystal is in range of 25 – 500 nm, in average of 85 nm; b) fine distribution of crystals. Figure6. FESEM of standard frit containing 3wt% TiO2 and 7wt% kaolin Table captures Table1. Composition of the standard frit Table2. Results of spectrophotometer and glossiness 1 à ¯Ã‚ Ã¢â‚¬ ºÃƒ ¯Ã¢â€š ¬Ã‚ ªÃƒ ¯Ã‚ Ã‚  Corresponding author. Tel.: +39 3886598606 E-mail address: [emailprotected] (A. Ghafarinazari)

Wednesday, November 13, 2019

That Was Then This Is Now :: essays research papers

That Was Then This is Now   Ã‚  Ã‚  Ã‚  Ã‚  This book is about two greasers named Bryon and Mark. Mark whose parents died when he was a young age went to live with Bryon. This book is in first person, and takes place behind the eyes of Bryon. The book first starts out by introducing the other characters in the novel: Charlie, a bartender who allows Mark and Bryon to come in to his bar, but wont let them buy booze. M&M a small longhaired child who always seems to be munching on M&Ms, and he lends Bryon and Mark money all the time. After their rendezvous with M&M the boys visit their mother in the hospital, and while their Bryon meets Cathy who is M&Ms sister who just came back from medical school. After a conversation, Bryon invites Cathy to go on a date with him, and Cathy accepts. Soon Bryon talks Mark into double dating with him, then he proceeds to borrow Charlie’s car. The next night Angela, who is Bryon’s ex sends someone to attack him, and who ends up attacking Mark. Mark is sent to the hospitable, but recovers in a day or two. The story then resumes with Bryon continuing to date Cathy, and Mark seems to become more and more jealous. One night Mark, Bryon, Cathy, and M&M decide to drive up and down the Ribbon to get M&M cheered up because his dad was ridiculing him for his long hair. The Ribbon is a long stretch of road that teens hang out. While driving along M&M gets out and walks away with a group of other long haired children, but because you cant stop on the ribbon on a green light all they could do is watch him go away. For the next few days Cathy and Bryon are searching the Ribbon while Mark mysteriously brings in large sums of money to pay for his mothers hospitable bill. Bryon notices this, but never asked Mark where he is getting the money. The next day Mark says he might know where M&M is. Mark discloses a hippy hangout, and that is where Mark goes, but without Cathy. Bryon finds that M&M had been there, but was not around that day. The next day Bryon an d Cathy go to the hangout and find M&M, and he was really bad.

Monday, November 11, 2019

Risks and Loyalties

As Markham was summoned into the conference room to begin his presentation to the board of the state pension fund, he was wrestling with whether or not to raise the liability issue. He knew there were risks either way. There was the risk that his client would choose to take their business elsewhere if he told them what he believed to be the fund’s financial reality. Furthermore, such a move would not only result in lost business, but would likely be interpreted as disloyalty towards his firm. But then he thought about what didn’t happen during the 2008 financial crisis, and this reality gnawed at him: When the subprime crisis played out everybody was asking why, even though there were all these people that had a role in making it happen, no one spoke up? And so does somebody who is playing a bit part in creating a reprise of the last crisis have a responsibility to speak up on behalf of the pensioners themselves even though this is contrary to the wishes of their employer and the board of trustees who has hired their employer to provide investment advice? We all commonly find ourselves in a position where we have to tell someone something they don’t want to hear. We face this kind of communication dilemmas all the time; at home, with friends and at workplace. The range can fall between just telling a friend about his look to the case with Harry Makham, who was facing the problem of telling the board of directors about the wrong liability numbers. There are usually 2 ways of responding to this kind of dilemmas, either â€Å"saying it just right† and falling into the category of confident communicator, or failing to inform and falling into the category of unethical cheater. There are at least 5 different approaches for overcoming ethical issues concerning communication dilemma: * The Utilitarian Approach – action that provides the most good or the least harm for all who are affected-customers, employees, shareholders, the community and the environment. * The Rights Approach- action that best protects and respects the moral rights of those affected * The Justice Approach- ethical actions that treat all human beings equally, or if unequally, then fairy based on some standard that is defensible. but there is a debate over CEO salaries that are hundreds of times larger than the pay of others) * The Common Good Approach- actions that lead to the welfare of everyone in community. * The Virtue Approach – actions that are consistent with certain ideal virtues and are consistent with your own values. Regarding the issue of telling clients things they don’t want to hear the Utilitarian Approach may be more useful, and certain factors should b e taken into consideration: * harm to the clients * harm to the firm * harm to the public * harm to environment * harm to yourself (your ethical views)

Friday, November 8, 2019

Live Liver Donation essays

Live Liver Donation essays Live Liver Donation Living liver donation is a relatively new phenomenon. The first procedure was performed in 1989 with adult-to-adult donations starting in 1995. In this report I would like to explore the assessment and procedure of live liver donation, the risks and effects, and the direction it is taking medicine in the future. The very nature of taking part of a living persons liver and implanting it into another person is cause for questions and curiosity. One might want to know what the long-term effects on a living liver donor are. Due to the recency of the procedure, data is not yet available on the long-term effects. Information so far is anecdotal in the sense there has been only one reported death and no published incidents of failing health as a consequence of living donation; there have been no formal studies we are aware of. The limited information on short-term effects suggests complications arising from the surgery are few and manageable. For the most part they are covered by insurance. Policies vary, and some may exclude this procedure as "experimental," so you'll want to check the insurance policy of the transplant recipient. (It is the recipient's policy that pays.) As with kidney donation, there is interest by some members of the general population in making a "non-directed" donation, which is a donation that goes to anyone waiting for a liver transplant. You can contact your local organ procurement organization to see if they have a program. It is also possible to donate to a friend or family member where there is an emotional but not a biological tie. The transplant center will let you know what their policy is concerning such unrelated donation. It is becoming more common to allow such donation, although United Network for Organ Sharing (UNOS) data show this form of donation is still unusual. Facilities performing the procedures cu...

Wednesday, November 6, 2019

Today a Boy, Tommorow a Man

Today a Boy, Tommorow a Man Free Online Research Papers People are often the products of their environment. A wealthy person has more of a chance to do the more pleasurable things in life than a person who is struggling to find food does. A person who is brought up in a household where no one drinks is less likely to become an alcoholic than one who is brought up in the home of alcoholics. A person’s environment can play a role even in simple things, like whether or not that person is allowed to grow up and mature. In The Man Who Was Almost a Man, Richard Wright depicts two sides to the main character in the story. He shows Dave as both a man in some ways, and a boy in others. Dave is as much a man as his environment allows him to be. Dave is in many ways a man. The first thing that should at least make Dave nearing manhood is his age. â€Å"Ahm seventeen. Almost a man. (Wright 1228) he says to himself as he strolls home after a hard day at work. A male nearing the age of 21 which is the age at which society calls a person a man, should be able to make mature decisions. Dave does make some mature decisions. He goes to work every day and does a good job. He tells his father Research Papers on Today a Boy, Tommorow a ManThe Effects of Illegal ImmigrationStandardized TestingBook Review on The Autobiography of Malcolm XCapital PunishmentHonest Iagos Truth through DeceptionTrailblazing by Eric AndersonGenetic EngineeringMind TravelPersonal Experience with Teen PregnancyHarry Potter and the Deathly Hallows Essay

Monday, November 4, 2019

Organisational Change Essay Example | Topics and Well Written Essays - 3000 words - 2

Organisational Change - Essay Example St. Mungo’s is a reputed charity that works for the vulnerable individual of the society. The employees engaged within St. Mungo’s are highly experienced and loyal towards the activities of the organisation. However, with the recent merger of St. Mungo’s with Broadway, the reliability and dependability of the employees declined and it affected the position of the organisation significantly. The employees called for a strike and it declined the success rate of the organisation in the upcoming days as compared to other competitors. The prime cause for the strike is the pay cut of the loyal and existing employees of St. Mungo’s. The non-monetary benefits that the employees received from the organisation are also restricted by the senior management with the help of reorganisation and hence, it proved negative for the employees. However, the restrictions are mainly applicable for the employees of St. Mungo’s and not for the Broadway staff. This is the ma in key reason that increased the anger of the employees of St. Mungo’s and hence, it resulted in the commencement of a strike (Kotter and Schlesinger, 2007). There are different types of organisational change that would be used by the managers to prevent the organisation from any sort of challenging situation. However, types of organisational change are segmented into two segments such as evolutionary and revolutionary change (Lewin, 2012). As per the view of Schein (2012), constant improvement may be possible only through evolutionary change.

Saturday, November 2, 2019

Cross cultural management Essay Example | Topics and Well Written Essays - 10500 words

Cross cultural management - Essay Example TABLE OF CONTENTS 1. Introduction 4 2. Literature Review 6 2.1. Background research on Leadership 6 2.2. Background Research on Cross Cultural Management 9 2.3. Theory of Hofstede 15 3. Leadership in Egypt 19 3.1. Current Situation 19 3.2. Challenges 20 3.3. Impacts 22 3.4. Implications for Managers in Global Management 25 4. Findings 26 5. Discussion 29 6. Conclusion & Recommendations 32 7. References 34 1. Introduction Leaders are not born, they are made. The most common myth about leadership is the converse of the previous statement, which indeed is creating waves of many more misconceptions amongst those aspiring leaders and entrepreneurs around the world. There was a time when only few men and women dared to question, rebel against odds, voice for the weak and talk for the helpless. But today there is a need for each one of us to dare, rebel, voice and talk, but like leaders and not losers. Andrew Carnegie’s thought provoking statement is worth a note here which states â €Å"No man will make a great leader who wants to do it all himself, or to get all the credit for doing it†. ... If we see the current trends of leadership, there are various personalities who have quoted many inspirational words about leadership and for the future leaders as well. We see Jeff Barnes quoting â€Å"There are no boundaries anymore.† This means the businesses and organizations are looking out for globalization and make their mark all over the world. In the last 10 years the world has seen a fast changes in the business world. When there was economic downturn started in December 2007, many of the interviewees had the thought that it is somewhat different than what was happened 10 years ago. According to Roland Smith’s saying this new environment is regarded as a perpetual whitewater. The Chief Executive Officers (CEO’s) of all the big and renowned organizations have backed the saying of Roland Smith and they were not sure as to how to tackle this changing environment as the equipments are were not available that time. In Egypt the most remarkable monument or st ructure is the Pyramid. If you notice Pyramid, you can see that the tip of it is painted with gold. The reason for that is to get connected with the sun. The Pyramids have always challenged the modern science to build something since the technology and skill sets of the manpower have been advanced with time. Today it has been more than a year since the reign of Dictator Mubarak is ended. Now it is high time for the country to look ahead and reform its social, political and most importantly economic stature. Today the country is in need of a leader who can coach and inspire the nation, which will help in mobilizing the country towards growth and prosperity. The well-known examples of this type of

Thursday, October 31, 2019

The Ku Klux Klan Essay Example | Topics and Well Written Essays - 1500 words

The Ku Klux Klan - Essay Example Much of their activities included horse riding during the night while wearing costumes such as masks. As these innocent night expeditions continued, the society, especially former slaves, begun exhibiting fear since they did not know the real intentions of the group, which they thought was out to cause trouble for them (Parsons 814). Young people enjoy being in control and this has been noted as one of the major motivation factors behind gang formation and membership. It is therefore not a wonder to find that after realizing the effects they were having on the surrounding community, the group begun recruiting more people and expanding their territories to the neighboring towns thereby leading to the emergence of numerous factions, which did not have an agenda or any formal leadership to promote a unified course. The lack of leadership and direction especially after the expansion of the group necessitated the group members to come up with a strategy to exercise control over the operat ions of the group so as to facilitate harmony, which was necessary in strengthening the organization. As a result, a meeting was called in 1867, in which General Nathan Bedford Forrest was appointed as the commander (Parsons 817). Bedford was a former confederate soldier, who had a lot of experience owing to his involvement in the American Civil War from 1861 to 1865. Although he never had formal military training, Bedford had natural talent in war planning and this impressed his superiors as well as his colleagues, and soon he was promoted to the rank of Lieutenant Colonel and was given the role of training and recruiting new soldiers into the army. This means that with him on the helm, KKK was bound to reach great heights to become one of the most influential in the American society. Other members were elected as leaders of smaller groups in order to establish a chain of command similar to that of the army and which was to facilitate discipline and unity among the different factio ns (Artoletti 22). The American Civil War ended in 1865 and paved way for the reconstruction era. Among the policies, which were to be adopted in order to facilitate reconstruction of the country was to promote the rights of black people and former slaves by allowing them to vote and vie for various political offices (McVeigh 16). They were also to be allowed to compete with the white Americans in the job market. In general, all Americans were to be accorded equal rights and privileges irrespective of their color, ethnicity or religion. However, majority of the whites did not take this positively as they felt that this would have created a lot of competition for resources and job opportunities, which were scarce especially within localities where the Ku Klux Klan operated. KKK members were not happy with this and as a result, members started becoming suspicious towards the non-whites, whom they perceived as inferior. Indeed, KKK started approaching the blacks trying to convince them to give up their quest for political offices because they were better off living as second class citizens and that they stood to benefit more if they agreed to remain as slaves, which did not bear any fruits (McVeigh 21). Instead, the blacks continued to demand their rights through activism. A widespread hatred towards the blacks and former slaves especially in the south boosted the membership of KKK as it provided an informal avenue for the

Tuesday, October 29, 2019

Chalice Wine Essay Example for Free

Chalice Wine Essay Chalice Wine Group is a publicly traded company that, through numerous partnerships, owns and/or operates a number of vineyards and wine manufacturing companies in California’s Sonoma valley. Previously, they enjoyed a time of profitability. Yet in recent years, expansion has saw a decrease in their level of profitability, followed by a repeating period of net income losses. The goal of the case is to determine whether the operation of a small winery can be a profitable venture. Upon reading the Chalice Wine Case, the primary issue that I have identified, is that the management of the company has not crafted a clear and identifiable mission. †¢As currently structured, Chalice Wine Group is attempting to be a â€Å"vertically† integrated company. In this they are attempting to accomplish ever step in the wine business. They are making their own grapes, processing their own grapes, bottling, and lastly shipping them to various distribution outlets. This is fine, as long as they are able to create an extremely efficient model to do so. But unfortunately, as their results indicate, they are not efficient enough to make this current model work. There are a number of possible avenues that Chalice Wine Group needs to explore, among those are: -Why are they paying a price for grapes(from themselves! ) that is so in excess of the market rate? There are currently some transfer issues in place, management needs to explore these costs. -Pressing and manufacturing of the wine: The costs of the machinery involved, is extremely expensive. What is Chalice doing with their equipment during the time periods in which there is no production? How are they utilizing this excess capacity? They can either outsource this to another company, or utilize this capacity to process wine for others. -Shipping and distribution: Why are they handling this process themselves? This is easily something that should be handled outside. †¢Secondly, they wish to be a niche wine provider, by manufacturing a high quality, high cost product. The problem is that this statement essentially contradicts their company’s vertical structure. This is illustrated through examination of some of their shipping/bottling practices and part of their distribution chain. -They do not package and bottle their products according to the same quality standards. For example, they are using different quality bottles and boxes for different products. In this eyes of the consumer, this can be inferred as different levels of wine quality. -Next, the desire to be a small niche provider is a direct contradiction to the thought of distribution through food markets. This alone can allow the consumer to infer a mass marketed, broadly distributed product of lower quality. If they want to be a niche provider, they need to market and distribute themselves as such. Chalice Wine Group needs to decide what kind of company they want to be, and as such, needs to structure themselves in a way that will help best meet that mission and goal in the most efficient manner possible.

Saturday, October 26, 2019

Critical perspectives on management and leadership

Critical perspectives on management and leadership There is a difference between what theorists believe managers should do, what managers believe they should do and what managers actually end up doing (Grint, 1995). Applying critical theory to determine what is what and who has what. Critical Theory The Frankfurt School of Critical Theory is the longest and most famous traditions of Marxism. This tradition is often referred as critical theory- meaning a special kind of social philosophy from its inception in 1923 by Felix Weil (Seiler, 2004). The critical theory of society of the Frankfurt School continues to excite interest and controversy (Kellner, 2001). A theory is critical to the extent that it seeks human emancipation, to liberate human beings from the circumstances that enslave them. A number of critical theories have emerged in connection with the many social movements that identify varied dimension of the domination of human beings in modern societies (Gutting, 2003). Thus, the term critical theory was used as the symbol of a philosophy which questions the effective order of political and social modernity through an order of immanent critique. It was mainly an attempt to regain a critical potential that had been overrun by recent intellectual, social, cultural, economic and technological trends. The term Critical theory has its origins in the 20th century Frankfurt School, and now is associated with scholars across a range of disciplines.   Its purpose of inquiry is to confront injustices in society (Clark, 2004).   Critical Theory has been deeply concerned with the fate of modernity, and has offered systematic and comprehensive theories of the trajectory of modernity. Critical theory began by putting Marxian political economy at the centre of analysis, and early critical theory was materialist and committed to socialism (Gingrich, 2000).   Critical theory has generally been committed to the idea of modernity and progress, while at the same time noting the ways that features of modernity can create problems for individuals and society (Kellner, 2000). This is much reflected on the 21st century, though there is progress in many things, but still issues like globalisation tends to pose important problems for the society.   According to Heilman (1998), being critical involves understanding the sets of historically contingent circumstances and contradictory power relationships that create the conditions in which we live.   Theory helps us to organize the world, to sort out the details, to make some coherent sense out of a kaleidoscope of sensations (Ayers, 1992). When theory is theorized, as stated by Heilman (1998), the imperatives of practice bring the theory down to the ground.   Phenomena are observed and experienced; this experience informs theory; and then the theory is further modified as a result of additional practice.   Rather like fiction writing, critical theorizing is a process of imagining and describing a non-real but possible world.   The critical theorists have deeply influenced contemporary social theory, communication theories, cultural theory and many more for a number of decades.   According to Clark (2004), Critical theorists are committed to understand the relationship between societal structures (such as economic and political) and ideological patterns of thought that constrain the human imagination and thus limit opportunities for confronting and changing unjust social systems.   Critical theorists emphasise that theory and research must serve emancipator interests, to create a world that satisfies the needs and powers of social actors (Sanghera, 2004).   According to critical theory, people are dominated by a false consciousness created and perpetuated by capitalism in order to preserve the hegemony of those in power (Meyer-Emerick, 2004).   Due to this cause, one can assume that it prevents people from freely pursuing their own interests.   This dissent is only dismissed if people begin to see the contradictions between the social construction of the world and their lived experience.   Critical Management Studies Critical management studies also known as CMS which is the known as the term that describes the a diverse group of people that has adopted the critical or questioning approaches to management, this term emerged of recent years. The report outline The above statement sets the mood for this report, as the report will be looking at how the critical management theory of yesterday applies to the modern western approaches of management today.   Another key aspect will be on trying to articulate the connections between the management perspectives of contemporary society in the critical theory.   The focus will be on Karl Marx and Michael Foucault as critical theorists and how their perspectives affect the management and leadership in today modern western era. Marx argued that capitalism, like previous socioeconomic systems, would inevitably produce internal tensions which will lead to its destruction. Just as capitalism replaced feudalism, he believed socialism would, in its turn, replace capitalism, and lead to a stateless, classless society called pure communism; Marx economic relationship between managers and the workers. Whilst Foucault argued that patterns in disciplinary behaviour found in management practices. management and leadership Scientific management Scientific management (Taylor System) also known as Taylorism is a theory of management that analysis and manufactures workflows to improve employee (labour) productivity. The idea was developed by a Frederick Winslow Taylor between 1880 and 1890, and it was the first published monograph (written documents). Frederick Taylor believed that decisions based upon tradition and the rules of the thumb should be replaced by accurate procedures that are developed after a study of an individual at work. This means that there is a high level of managerial control over employee work practices. Scientific management is a distinction on the theme of efficiency; it developed in the 19th and 20th century were instance of large recurring theme in the human life of increasing efficiency, decreasing waste and using experiential methods to dictate what matters rather than accepting pre-existing ideas of what matters. Management today is the greatest use of scientific management is a form to contrast a new and improved way of doing business. Leadership Leadership is having the ability to give guidance to those that will follow. Those that follow will help to complete the mission. It is an immature science and the body of knowledge in the field has developed through a series of fits and starts. Leadership is a soft science, just as anthropology, sociology and psychology. It can not be proven exactly what it is. Leadership is an art; the skilful application of leadership behaviours beyond techniques is much the same as the skilful application of brushstrokes by a master painter. Leadership is both rational and emotional. It involves both sides of human experience. It includes actions and influences based on reason and logic as well those based on inspiration and passion. Leadership is a social process shared among all members of a group. (Yolk, 2002) Leadership also involves in political activity as in power activity; conversely, it is much more like transformational leadership. Political processes involve efforts by members of the organization to increase their power or protect existing power sources (Pfeiffer, 1981). Although the ultimate source of political power is usually authority, control over resources, or control over information, political power involves influence processes that transform and magnify the initial basis of power in unique ways Karl Marx A Marxists thought is based on this lifestyle, a science of logic called Dialectics. Thus, Marxism is both a theory and a practice. The theories of Marxism are based on a scientific method of thought called dialectal materialism.   Theory is based on a particular set of conditions that are always finite, and thus, any theory is necessarily limited. To test the validity of theory, Marxists rely on empirical evidence as the criteria of truth (Basgen, 2005). Marxism embraces modernity and Marxists argue that one of the main problems is that capitalism puts fetters on the progressive forces. The forces of capitalism are viewed as progressive in sweeping away the traditional, religious, backward, and feudal forms of society, spreading industrialisation and urbanisation across societies (Moody, 2003). Michel Foucault His studies challenged the influence of German political philosopher Karl Marx and Austrian psychoanalyst Sigmund Freud. Foucault offered new concepts that challenged peoples assumptions about prisons, the police, insurance, care of the mentally ill, gay rights, and welfare (Ron, 2000). The main influences on Foucaults thought were German philosophers Frederick Nietzsche and Martin Heidegger.   The connect.net website, describe Foucaults thought as explored the shifting patterns of power within a society and the ways in which power relates to the self. He investigated the changing rules governing the kind of claims that could be taken seriously as true or false at different times in history. critical analysis Marx critique of capitalisms Capitalism is the system that upholds the relationship between the owners of the means of production and workers. The former comprise the bourgeois class and the latter the proletariat Marxs critique of capitalism was that while this system had incredible power and potential to transform human society positively, in actual fact it resulted in exploitation and ultimately limited the possibility for further improvement (Powell, 2001). Moody (2003), describe this environment as workers were emancipated from traditional limits but became slaves of the new factory system, monopolisation resulted in limits on trade and further progress, and the state acted in the interests of the bourgeoisie rather than society as a whole. Commodity Fetishism Labour Power To be clear about is what the capitalist has bought. The worker has sold not his labour but his ability to work. This Marx calls his labour power. Also, as Marx defines, labour power is the abstraction of human labour into something that can be exchanged for money. In addition, capitalism can purchases labour power as a commodity. In other words, Labour power is a commodity governed by the same laws as other commodities. Its value is determined by the labour-time necessary for its production. Labour power is the ability of the worker to work. It is consumed by the capitalist in the actual labour-process. (R.Sewell and A.Woods) Marx explains, I use the term labour power or capacity for labour, to denote the aggregate of those bodily and mental capabilities existing in a human being, which he exercises whenever he produces a use-value of any kindà ¢Ã¢â€š ¬Ã‚ ¦ The value of labour power, like that of every other commodity, is determined by the labour time necessary for the production, and consequently for the reproduction as well, of this specific article as well. Capitalism Power As Campbell (1981:34) describes, à ¢Ã¢â€š ¬Ã‚ ¦as in slavery, where the producers themselves are owned by the slavery owners; in feudalism where the land is owned by the landlords; or in capitalism where machinery and factories (capital) are owned by capitalists. In capitalism, the machineries and factories is not the only thing owned by capitalists (or factory owners), also labours. For example, in a car making factory, all the machineries are fixed assets to the factory owner, machineries can not make profit for the factory owner if no one operates them, and so labourers who operate machineries are the main assets to the factory owners. In addition, labour power is a commodity (which is bought and sold on the labour market), (The Marxist critique of capitalism) because it has an exchange value. As Campbell (1981: 38) says all commodities labour power has an exchange value, its price (the wage), yet again like all commodities, it also has use value to the purchaser. The purchaser here is any capitalism or any factory owners. It continues one purchased, like any commodityà ¢Ã¢â€š ¬Ã‚ ¦ Labour power is owned therefore, like a machine, and is put to work (Campbell 1981:38) As the labour power is a commodity, so once it is purchases by factory owner, the owner has the power to either use it or exchange it to others. Also, in capitalism, once the owner purchases new labour power, he has the rights to make decision on how much he will pay to his new labourers, and how long the new labourers will work every week; also he can fire any of the labourers in his factory any time if he feels not satisfied with them. à ¢Ã¢â€š ¬Ã‚ ¦ in a capitalist economy the vast majority of people have only their labour power to sell in order to gain income with which to purchase food, clothing, housing and other goods and services. The means of production are owned by the capitalist class and if they are unwilling to hire labour, or wish to reduce the numbers of workers they employ, this puts workers prosperity immediately at risk (Campbell 1981:111) Marxs argument was against capitalism, which he referred to as a stage at which every society must go through that can bring about the seed of its own destruction. He indicated that human essence was labour and physical effort needed in the production of the means of subsistence. Hence, some forms of production are needed for survival. The suggestion being that it is acceptable for oneself but not for others because some individuals may have all factors of production (capital, entrepreneurship, labour and land), while others may have nothing but just their own labour, which eventually will result in uneven distribution of wealth and income. Additionally, Marx argued that capitalism deprives the labour force of their creative fulfilment, and since they are portrayed to be the already planned part of the production process, they are unable to achieve self-actualisation. Exploitation and Alienation For Marx, this alienation works as a process, but it can be broken up into 3 different aspects for analysis. The first aspect of alienation under analysis is how workers are alienated from the product they produce. Under capitalism, the object the workers produce is surrendered for the wages they receive. The workers then loose any relation to the object they are producing because they are handing it over. This is of course is different from the system of self-sufficiency, where the workers have a much more direct relationship with the object that they produce. As the workers become more independent of their product, they transfer power to the employer. As mentioned with Marxs critique on the political economy, the more objects the worker produces, then the more power the employer possesses which will lead to a greater weakness to the workers. Therefore under this system, the workers are only competing to be exploited. This is a form of alienation, because the object that the worker produces becomes an alien entity to him, independent of his control and ultimately controls the worker. Another aspect of alienation that Marx examines is how the self becomes another alien entity to the worker. Under the mode of capitalism, the working conditions are established by the capitalists and not by the workers themselves. These conditions are established along the grounds of the capitalists drive for profits, rather than the workers need for self-fulfilment. Marx felt that self-fulfilment was a major aim of a person, and felt that under the system of capitalism, where your working conditions are created by your employer, it was impossible for the worker to gain this self-fulfilment. He also felt that the capitalist employers were victims of this problem too because if they didnt drive for profits, then they would be put out of business. The labour itself is described by Marx as exterior to the worker, that is, it does not belong to his essence. Therefore he does not confirm himself in his work, he denies himself, feels miserable instead of happy, deploys no free physical and intellectual energy, but mortifies his body and ruins his mind (David McLellan 2000). Explain Marxs articulation of exploitation. The practice of mistreat of workers in an environment that is deliberately designed to maintain it, i.e. capitalism, Marxs conforming the workers alienated by/owners of the means of production to gain profits at the expense of the workers (e.g. managers forcing employees to undertake tasks outside their job description in order to cut costs and maximise profits) because people are alienated they conform to the demands of their employers in order to keep jobs safe. Foucault disciplinary Power Moves away from the economics of Marx. Looks at power and reconceptualises it. Management as a representation of power relations in society. Specific rules maintain, regulate and institutionalize practices in a work environment (office, factory, school, etc), Power- Disciplinary power the panopticon as a illustration of society, the middle tower is all seeing yet prisoners always obey without knowing for certain whether they are being monitored, by whom or by how many. The result is the creation of self-regulating, obedient and disciplined prisoners (at least in theory). Relate this form of disciplinary power to management. Power as the central driving force in a society within a group of people in a working environment. Manager doesnt create a system the manager merely plays along with the rules, thus maintaining the relations of dominance and dominated. Critical Analysis on Leadership Over the influence process of leadership, it needs power. (Northhouse, 2007). Leaders are usually described as wielders of power in the discussion of leadership because they are individuals who dominate others. Power is the capacity or potential to influence another party (Mint berg, 1983; Pfeiffer, 1981, 1992). It is talked as the basis of leadership according to many political theorists like Machiavelli through academic political scientists such as Marx in the twentieth century. People have power when they have the ability to affect others beliefs, attitudes, and courses of action. Ministers, teachers, doctors, and coaches are examples of individuals using power to effect change in people. In commercial, there are two major types of power, position power and personal power (Bass, 1960; Etienne, 1991): Position power refers the power a person derives from a particular rank in a formal organization system, for example, department heads have more power than clerical staff in position. It includes potential influence derived from legitimate authority, control over resources and rewards, control over punishments, control over information, and control over the physical work environment.   Personal power refers the power a leader derives from followers. It includes potential influence derived from task expertise and potential influence based on friendship and loyalty. Followers give leaders power when leaders act in ways that are important to them. Power is also inherent in a persons position in the organization. (Bass, 1960; Etienne, 1991) According to Northhouse (2007) the current dominant leadership paradigm is the transformation approaches which is a process that changes and transforms people. The elements at the heart of transformational leadership are: idealised influence, inspirational motivation, intellectual stimulation and individual consideration. Critical Analysis on Scientific management The Marxist theory of capital sees labour as a cost of production resulting in the alienation of workers as the need for labour surfaces from the physical needs defined by the fundamental relationship between humans and their physical environment (Hatch, 1997, p.27).   Taylors ideas on scientific management (1990) have similar economic themes to Marx and Adam Smith.   By viewing management as a science, he broke down the managerial problem into stages of research, definition, analysis and implementation.   His principles were inherently based on the assumption that people put in as little effort as possible into their work and were soldiering on in order to earn money.   This shifted all the responsibility from the worker to the manager and scientific methods were used to determine the most efficient way of working.   After selecting the best person capable of performing the task, they were trained to work efficiently and their performance was strictly monitored.   In hin dsight, though this may have appeared to be a good generic strategy for the success of a firm, it heavily depended on whether the optimal method of producing could be found and whether or not the strategy was implemented correctly.  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   conclusion