Clandestine chemistry

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    Membranes

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    A membrane is defined as a thin sheet, film, or layer, which works as a selective barrier between two phases that can be liquid or gas.113 In other words, a membrane is an interface between two adjacent phases acting as a selective barrier, regulating the transport between the two components.114 Membranes have gained an important place in chemical technology and are used in a broad range of applications.115,116,117 The key property that is exploited is the ability of a membrane to control the…

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    The synthesis of Aa-g-poly(MAA) involve the optimization of various reaction conditions like initiator concentration, monomer concentration, crosslinker concentration, solvent concentration and pH. After the optimization of various reaction parameters the replications were carried-out in triplicates for the reproducibility of the results and statistical of the results obtained. It was performed using the Statistical Package for Social Science (SPSS) version 10. Statistical results of the…

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    composite has been investigated. For that purpose, the PMMA samples with Al2O3 additive prepared with different percentages(0,15,25,35 and 45) wt.% and different thickness. The experimental results showed that the D.C electrical conductivity increased with increasing the alumina concentrations and temperature. Also the activation energy change with increasing of additional alumina. The dielectric constant, dielectric loss, A.C electrical conductivity are changed with change the concentration of…

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    Feed Flow Rate Essay

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    4.2.4 Effect of Feed flow rate (Fgr) on Product Distribution An increase in the flow of gas oil means an increase in the velocity of the gas oil feed, also a decrease in the residence time of the gas oil in the riser; hence a rise in the conversion of gas oil and yields of the products is expected(Akpa et al. 2010). When the flow rate of gas oil is increased, there is an increase in the heat inflow into the reactor, rate of cracking reactions are high, feed also spends less time in the reactor…

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    1-[Cyano(4-methoxyphenyl)methyl]cycloalkanol (VF-I) synthesized through the reaction of p-methoxyphenylacetonitrile and cyclohexanone using aq. NaOH and tetrabutylammonium hydrogen sulfate as PTC. NaBH4 and CoCl2 in 2:1 THF: H2O used for the reduction of VF-I to obtain 1-(2-amino-1-(4-methoxyphenyl)ethyl)cyclohexanol (VF-II). Further, venlafaxine derivative of the amino acid -carboxamide (VFCA-I toVII ) synthesized through coupling of N-Phthaloyl amino acid chloride derivative (2a-2g-…

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    Essay On Water Rocket

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    Introduction and Overview: For this extended essay, I will be working on building and optimizing different sized water rockets to find out the optimum amount of fuel (water) for each the different rocket sizes. I will be measuring the ranges at which each rocket will fly to find out the optimum fuel level. A brief summary of water rockets: A water rocket is made up of a selection of parts to provide its successful launch: the nose cone which will make the rather snub-nosed end of the large…

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    Redox Catalyst Essay

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    1. Redox Catalyst Catalyst is defined as a substance that increases the rate of a chemical reaction without changing its chemical composition and affecting the standard Gibbs free energy, by lowering the activation energy of a chemical reaction. It does so by providing an alternative reaction pathway. In redox reaction, the key chemical event is the net movement of electrons from one reactant to the other. The oxidation state of atoms are changed. Transition metal is used as redox catalyst due…

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    Demitri Mendeleeve was a Russian chemist who invented the first periodic table in 1869. The periodic table he made was very different from the modern day periodic table we know today. Henry Moseley updated Mendeleev's version of the periodic table in 1915. This is more like the periodic table that we know and use today. The only difference is that there has been many more elements added. Mendeleeve also had predicted a lot of the characteristics and properties of elements that would fill up…

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    2. The gas phase catalytic oxidation of benzene reactor model and evaluation of the parametric sensitivity To illustrate the parametric sensitivity analysis, the case of gaseous phase catalytic oxidation of benzene to maleic anhydride was considered (LupuČ™or et al., 1981). The multi-tubular reactor (heat exchanger type) with the fixed bed catalyst inside a small diameter tubes (under 3 -4 cm) is continously cooled by molten salt mixture (nitrates and nitrites mixture; Maria , 2007). The raw…

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    3.1. Chemical composition and monosaccharide analysis Polysaccharide molecules are linked together by water molecules through hydrogen bonds in an aqueous solution. Adding ethanol into aqueous solution of polysaccharide initially dehydrate polysaccharides, enhance intra-molecular hydrogen bonding, cause conformational change and aggregation of polysaccharide molecules, and eventually leads to the precipitation of macromolecular chains, and the following addition of alcohol solvent gradually…

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