THE APPLICATION OF CHEMISTRY IN ENVIRONMENT
Year:2010 | Volume:1 | Issue:4|Papers Count:8

Safe water supply needs of living creatures; especially human life is the need to control it using a quality control laboratory tests and indexes is different. Standards for water quality parameters in water resources (including rivers, lakes and...) from different experts are used primarily to control the quality index calculated from results obtained for several tests that show water quality is. Water quality index to compare the quality of water resources with other resources and also to determine the health of a watershed in the different parts are used. Meanwhile, water quality control for a specific time period to understand the changes in water ecosystems are also used.

Isoxazole compounds which have various pharmacological, biological and industrial applications. Especially these compounds show the antivirus activity. It has been proved that they are effective in cure Parkinson and Alzheimer disease. In present research four kinds of isoxazole and an oxime compound have been synthesized. At the first, 4-Methoxybenzaldehyde changed into 4-methoxybenzaldeidoxime (1) by increasing sodium hypochlorite to hydroxylamine hydrochloride in pyridine as a solvent, the compound 1 changed to nitrile oxide and [2+3] cycloaddition happened by using propargyl alcohol, as a result 3- (4- methoxy phenyl) isoxazole-5-yl) methanol (2) was prepared. At the rest of the research 4- (5- hydroxyl methyl) isoxazole-3-yl) phenol (3) was prepared by reaction of HBr and compound 2 and acetic acid. Also, 2-boromo-4- (5- (hydroxy methyl) isoxazole- 3-yl) phenol (4) was prepared by reaction of Br2 and compound 3 in CH2Cl2. In the final step compound (4) was added to Br2 and CH2Cl2, and 3- (3-bromo-4-hydroxy phenyl) -4-bromo-5-hydroxy methyl isoxazole (5) was prepared. The structures of synthesized compounds were confirmed by FT-IR and 1H NMR spectroscopies.

Hydrophobically modification of potato starch was successfully carried out by mild esterification using acyl chlorides (octanoyl, lauroyl, palmitoyl chloride) in aqueous media, which resulted to good yields. Starch esterification was performed with long chain fatty acid chlorides (C8, C12, C16) in two steps, in the first step, starch dispersed in the reaction medium was alkali treated and the second, esterification. Samples of hydrophobic starch esters were synthesized with moderate degrees of substitution (DS-values<0.45) and reactivity of potato starch with this reaction conditions was studied. The chemical structural characteristics of the obtained products were investigated using common spectroscopy methods (FTIR and 1H NMR spectra). Starch nanoparticles and nanodispersion solutions were prepared via dialysis method. Particle size distribution of the nanoparticles determined with using laser diffraction particle size analyzer in aqueous dispersion. The morphology investigation of the starch and the grafted starch nanoparticles was carried out by SEM after freeze drying.

An 1D hydrodynamic model has been simulation and developed for gas hold-up and liquid circulation velocity prediction in air-lift reactors. model is based on momentum balance equations and has been adjusted to experimental data collected on a pilot plant reactor equipped with two types of gas distributors and using water as the liquid phase.The model equations described previously constitute a set of non-linear equations which are solved by an iterative procedure (v.b) (c plus). This model has also been combined with mass transfer and the kinetics of a chemical reaction to yield a complete model of the performance of a reactor.

The light and heavy hydrocarbons, phenol and the other organic material if without treatment charge in to the environment it can be increase the risk of environmental of pollution. For the treatment of these wastes the separator of oil from the lipids and then the biological process for completely remove the organic materials can be used.

This paper presents the results of heat transfer measurement and analysis for two 5*5 cm porous channels. the channels were made of bronze beads with two different mean diameters, dp=0.72 and 1.59 mm. the local wall temperature distribution and heat transfer coefficients were measured for heat flux of 8000 and 16000 watt/m2 with coolant fluid velocity ranging from 0.16 to 5 m/s and inlet fluid pressure of 1~3 atm. the flow of fluid in porous channels is modeled with using Darcy-forcheheimer-brinkman model. By using fluent software, simulation is done that the geometry figure with gambit is generated.

Biotreatment of mixtures of H2S and NH3 gas at various ratios was studied using a three-stage bench-scale bio filter inoculated with thickened municipal activated sludge and packed with a mixture of compost and pieces of hard plastic as a novel biofilter medium. This study investigated the elimination capacity, the removal efficiency, and variations of pH in the packing material, and the effect of inlet loads of H2S on the removal of NH3. At a loading rate of 8.32g NH3/m3 h and 8.32g H2S/m3h (concentration ratio of 2: 1) and an empty bed residence time of 60 s, the biofilter had an elimination capacity of 8.22g NH3/m3 h and 7.42g H2S/m3 h with a removal efficiency of 98.8% and 89.18%, respectively. At a loading rate of 8.32g NH3/m3 h and 16.64g H2S/m3 h (concentration ratio of 1: 1), an elimination capacity of 7.48g NH3/m3 h and 15.03g H2S/m3 h, and a removal efficiency of 90% and 90.3%, respectively, was observed. Nevertheless, at a loading rate of 4.16g NH3/m3 h and 16.64g H2S/m3h (concentration ratio of 1: 2) under same conditions, the elimination capacity and removal efficiency for NH3 was reduced to about 3g NH3/m3 h and 72.34%, respectively. The H2S elimination capacity and removal efficiency remained high at 14.90g H2S/m3h and 90.11%, respectively. The reduction of ammonia elimination capacity, in spite of a decreased NH3 loading rate was due to the acidification of the packing material and reduction of the pH value from 7.4 to 6.6. The Results indicated that the oxidation of a large amount of H2S would involve some environmental stress on nitrification bacterial growth and activity.

metalworking and cutting machining operations (soapy water) is a name that part of the oils or liquids is called for cooling or mental work when the metal cutting operations, cutting, working holes and.....That are used since the lubricants and fluids are operating with widely used and are everywhere, pollution from these materials as widely, but values are low. Pollution from lubricants and fluids, and high levels of operational focus as can be seen. In this article, environmental and health effects of cutting oils, and machining operations base oil (soapy water) on humans and the environment will check.