Synthesis of Mesoporous Silica MCM-41

Synthesis of Mesoporous Silica MCM-41 Results and Discussions The present study included the synthesis of mesoporous silica MCM-41 and its modification by impregnation of different metals on the mesoporous to enhance the photocatalytic activity of metals i.e Cu/MCM-41, Fe/MCM-41, CeO2/MCM-41. FTIR analysis of catalyst MCM-41 has the ability to impregnate numerous metals on its surface. MCM-41 was modified with metal salts in order to dope the metals on the surface of mesoporous material was characterized by FTIR analysis. The FT-IR spectra furnished the information about the incorporation of metals on the surface of MCM-41. The FT-IR spectra of synthesized material in the region of 4000 400 cm-1 in transmission mode using platinium ATR, a single reflection sampling module spectrophotometr, and shown in Fig. 5. The uncalcined MCM41 and calcined MCM41 spectra (Fig. 5A. a, b) show intense band at wavenumber 1100 and 802 cm-1 which accounts for the asymmetric and symmetric stretching of the Si-O-Si bonds, respectively.[i] The bands at 970 cm-1 and 460 cm-1 was assigned to the stretching and bending vibrations of surface Si-O- groups respectively.[ii] The sharp peaks at 2864.72cm-1 and 2922.14 cm-1 were due to the presence of surfactant before calcinations of MCM-41.[iii] For calcined MCM41, the bands at 2852 cm-1 and 2921 cm-1 corresponding to the long chain of alkyl group of the surfactant molecules were disappeared after calcination shows the completely removal of surfactants molecules. The differences of the intensities of the peaks in the FT-IR spectra of MCM-41 and MCM-41/ CeO2, are abserved which resulted from the doping of CeO2. A strong absorption peak at 1,632 cm−1 is observed in the spectra of MCM-41/CeO2, and it indicates the formation of Ce-O-Ce.[iv] About copper and iron also add TGA analysis of MCM-41: XRD analysis of MCM-41: Photocatalytic studies by using the metal dopped MCM-41: The metal dopped MCM-41 was studied for the photocatalytic degradation of commonly used pharmaceutics including salts of diclofenac (non-steroidal anti-inflammatory drug (NAID)) and atorvastatin (antihyper lipoproteinemic drug). For this purpose the solutions od these drugs were prepared and degradation potential of metal dopped mesoporous silicate was studied by optimizing various parameters i.e the amount of catalyst, the pH, the light, substrate concentration, metal loading on MCM-41. Effect of pH The interaction between the pharmaceutics and metal dopped mesoporous are dependent on the pH of the solution therefore the optimization of pH is important to achieve maximum degradation efficiency. During the present study, the degradation process was optimized by changing the pH from 3.5 to 10.5 over 10 wt% M/MCM-41(M= Cu, Fe, Ce) with 1 g l_1 of 0.114 mM drug solution. The pH of the pharmaceutic solution is adjusted with 0.1 M HCl and 0.1 M NaOH. The results obtained are shown in Fig. 3d. At acidic pH, the rate of degradation is faster as compared to high and neutral pH. The results clearly show that acidic pH is ideal for the degradation of the pharmaceutics. Effect of light intensity on degradation of pharmaceutic: The photolysis of pharmaceutic was studied under UV irradiation and dark. The log natural decay curves (In Ct/Co) of pharmaceutic versus irradiation time were displayed in (Fig. 3-5). The data for dark control samples were also elaborated in Fig. 6. Photodegradation of diclofenac sodium and atorvastatin under UV light in distilled water and methanol respectively were determined during the summer season (March-september) as displayed in Fig.3. The determined half life of 50 ppm diclofenac sodium in distilled water under UV light was 2.5h and in dark it was observed as 3 h. The rate of reaction varied from 2.8Ãâ€"10-3 to 2.3Ãâ€"10-3 when pharmaceutic was shifted from UV light to dark. Effect of metal loading on MCM-41 The effect of metal loading over MCM-41 on the photocatalytic activity is investigated and the results are shown in Fig. 2a. The degradation studies are carried out with increase of metal (wt%)5, 10 and 15 using 1 g l_1 of catalyst amount in 50 ml pharmaceutics solution. It is observed that 5–10 wt% increase in metal loadings, the photocatalytic activity increases and there is not much degradation rate at higher loadings. Among all the catalysts, 10 wt% M/MCM- 41 (M= Cu, Fe and Ce) showed most efficient photocatalytic degradation of pharmaceutics i.e., complete degradation within 90 min. The loss in the activity with increase in metal percent loading is due to the excess amount of metal oxide dispersed over MCM-41 that blocks the mesopores results a decrease in adsorption capacity. The turbidity of the solution also blocks penetration of light into the solution. Thus, the metal loading over the support clearly shows that one has to optimize the metal content, simultaneously re taining the active sites for adsorption in order to achieve the effective synergism. Effect of catalyst amount To optimize the amount of catalyst required for effective pharmaceutic photocatalytic degradation, different catalyst amounts (0.25–1.5 g l_1) are studied with 10 wt% M/MCM-41 and the results are shown in Fig. 3a. It is observed that 1.0 g l_1 is found to be the optimum. By increasing 0.25– 1.0 g l_1, the photocatalytic activity is increased and at higher contents the activity is not beneficial. This may be due to the fact that higher amount of the catalyst is obstructing the path of light penetration into the solution (i.e., scattering of light) thus reducing the OH radicals formation. Effect of substrate concentration The effect of 0.094, 0.1571 and 0.2829 mM pharmaceutics concentrations are performed over 10 wt% M/MCM-41 catalyst with 1 g l_1 amount for degradation. From Fig. 3b, it is observed that at lower concentrations, the adsorption is more compared to higher concentrations. There is a slight difference in degradation at 0.094, 0.1571 mM concentrations in comparison to 0.2829 mM. Also, it is acknowledged that the degradation is solely depends on the OH radical formation. The production of OH radicals is not sufficient in comparison to the amount of pharmaceutic adsorbed on the surface of the photocatalyst at higher concentrations. In view of this it suggests that, there should be equilibrium between adsorption of reactant molecules and OH radicals generated from the active sites. The 0.1571 mM concentration of pharmaceutic is found to be optimum for 10 wt% M/MCM-41 catalyst using 1 g l_1 amount. The experimental kinetic data are presented in Fig. 3c (inset) and in Table 1, along with time r equired for 50% degradation (t1/2) for each of the fitted lines. The degradation rate of pharmaceutic is decreased while increasing the concentration. The rate constant ‘k’ decreases with increase in initial concentration of drug. The effect of initial concentration of pharmaceutic on the photocatalytic degradation rate is described by pseudo-first order kinetics. The apparent rate constant for 0.114 mM IPU over 10 wt% TiO2/Al-MCM- 41 catalyst is 0.072 min_1 (R2 = 0.994). In the present investigation, 0.1571 mM concentration is found to be the optimum for degradation studies. [i] E.M. Flanigen, H. Khatami, H.A. Szymanski, (1971), Infrared structural studies of zeolite frameworks. In: E.M. Flanigen, L.B. Sand (Eds.). Molecular Sieve Zeolites. ACS Adv. Chem. Ser., 101: pp 201-227. [ii] E.M. Flanigen, H. Khatami, H.A. Szymanski, (1971), Infrared structural studies of zeolite frameworks. In: E.M. Flanigen, L.B. Sand (Eds.). Molecular Sieve Zeolites. ACS Adv. Chem. Ser., 101: pp 201-227. [iii] Taib, I.N., Endud, S., Katun, M.N Functionalization of mesoporous Si-MCM-41 by grafting with trimethylchlorosilane, International journal of chemistry, 3: 3(2011). [iv] Song, X, Qu, P, Jiang, N, Yang, H, Qiu, G: Synthesis and characterization of MCM-41 materials assembled with CeO2 nanoparticles. Coll. Surf. A Physicochem. Eng. Aspects 313–314, 193–196 (2008)

Julius Caesar Essay: Decision Making in Julius Caesar -- Julius Caesar

Decision Making in Julius Caesar Making the right decisions is an ongoing struggle for man, because making decisions is never easy, and the wrong decision can lead to endless perils. Decisions must be made when dealing with power, loyalty, and trust. Yet, unlike other decisions, ones that are about these three fields are the most important, due to the risk involved, and because of the consequences that might follow. Power- power is the complete domination of others, and since all men want to dominate those around them, power is valued as one of the most important possessions. Power is highly sought after, thus the correct decisions must be made to obtain it, and this is clearly proven by Shakespeare's "Julius Caesar". Power is obtained much easier than it is kept. "Liberty! Freedom! Tyranny is dead!" The conspirators celebrate the death of Caesar, because they believe that they make the right decision in killing him, and so far they have, but the decision to spare Mark Antony is one that will haunt them in the end. Power is not always beneficial, it can be a very dangerous possession. "You shall not stir out of your house today." Calphurnia makes the decision to persuade Caesar to stay home, and not go to the Senate meeting. When one has power, there are those who want it, like Brutus and the other conspirators. Calphurnia makes the right decision, yet Caesar makes the wrong one by deciding ... ...imminent. In the course of man's life he will have to make many decisions, and some will decide his future. Power, loyalty, and trust, are essential, yet obtaining them is only the beginning, managing them is a much harder task. For one to succeed he must realize how much power is beneficial and how much is dangerous. Loyalty helps one's cause immensely, yet one must not take the loyalty of his followers to the extreme. Trust is one of the most important assets a man can have, he must be careful, and not take it for granted. Man must always be prepared for these times when a decision must be made, because, as seen in Shakespeare's "Julius Caesar", one irrational decision can be man's last.

Impact of Market Revolution Essay

The end of the war of 1812 brought a large amount of pride to the Americans. From then on came about the transportation revolution which brought about many changes. The major shift from an agrarian to an industrial economy introduced various changes not just in politics but at the lives of many americans. The beginning of the market revolution marked the ending of the Federalist presence in the government while introducing a variety of modifications to the jeffersonian-republican party. These economical and political changes gave about notable chances in the status of labor, the class structure ultimately affecting the lives of american families. The market economy introduced many changes to the job industry by giving rise to the industrial worker most notably in new england. The many mills during the early 19th century were composed of women who seeked to better themselves, in part these women had to submit to their bose’s will when it came to their unstable wages. Even so the vast amounts of jobs that were left unfulfilled gave rise to immigration from Europe. The introduction to the Irish and German immigrants gave rise to wage jobs from skilled jobs which erupted many notable riots from the residents around New England. The waged workers were regarded as â€Å"wage slaves† by many riots due to them having a job that consumed most of their time as well as because of the unstable wages. These eventually led up to the creation of various workingmen parties. The most notable change that occurred during the 1820s was the rise of the new middle class which included doctors and teachers just to name a few. and the fall of the artisan class. This gave rise to the merchants in the class structure as they were the most benefited from the market revolution. The classes played a very important role during the market revolution. The difference of sexuality affecting wages still persisted. Even so, the rise of education during the second great awak ening allowed for better opportunities to become a â€Å"self made man† diminishing the dependence of workers on their bosses. The most affected thing during the market revolution was perhaps the life of american families. The role of the wife and the children changed to a certain point. The wife was expected to provide emotional and spiritual to the husband and her children and caring this being what the cult of  domesticity promoted. The increasing economic gap between the rich and the poor prevented excessive breeding this being due to the economic burden that children were viewed as. This led to the increase of child labor in industrial factories and mills. The market revolution brought many changes with it these heavily influencing the status of labor, the class structure ultimately impacting american families. The shift from an agrarian republic brought changes such as waged jobs while introducing a great influx of immigrants. The widening gap between the rich and the poor were in it’s part negative but in it’s part was positive when it came to education. The life of american families was perhaps the most affected with the introduction of the cult of domesticity and the ideals that reform movements engraved on married women Planning Status of Labor: People began to work on a timely schedule Received hourly wages Development of industries and factories Seed drill, reaper, cotton gin, steel plow increased production rates and made work easier Samuel Slater’s American Factory System Lowell textile Mills Workforce composed of women Young unmarried women hired Mostly from farms Under the promise of wages ; Unstable Wages Class structure: Artisans were going down the social class Women and children were inferior to men received lower wages than men Wealthy merchants were going up the social class ere heads of industries and factories

Choosing the Right Message Program essays

Choosing the Right Message Program essays Audience: People who use the Internet and who are looking for an instant message program. Chatting online can be very fun sometimes, but it can be annoying if you don't have the right Instant Messenger. Choosing an instant message program is hard, and some offer many different options. MSN Messenger, ICQ, and AOL Instant Messenger are just a few of the leading brands, but each program offers different features. MSN Messenger allows anyone with a Hotmail or MSN address to use this program. This program allows you to see when someone is online and permits you to send instant messages. A great feature I like is the typing bar. This bar displays a message when the other user is typing. This is great because you are not interrupting someone thoughts when they are typing. MSN also integrates file transfers into the program. These transfers are faster than any other program. MSN also has Video Conferencing in their program. MSN can also page someone from his or her program. This is also good if you don't want to give out your pager number. ICQ is a chat-based product, which offers features such as user details. User details tell you information about other users. This information includes time information, addresses, and phone numbers of the user. ICQ also allows you to talk to the person instead of just chatting. This feature is called voice chat. ICQ also allows you to leave a message for someone. When the user logs on, they receive any messages you left. ICQ has just about the best search engine feature. This is a great way to help you find people in your area and people with the same interest. Downloading mp3 files is just another feature that helps make this a good download. This is similar to Napster, and it is still illegal. AOL Instant Messenger is about the most popular program, but it does not offer the best features. This program includes the basic chat function. It doesn't include any of the special features mentioned abo...