Journal of Applied Biology
Year:2002 | Volume:15 | Issue:2|Papers Count:7

Because physical changes are calculabe within mathematics by means of equations and especially because for a model designer these equations are of a "partial differential" sort and are often not "analyzable", the importance of their numerical solution is rendered ever more conspicuous not only from a practical (and algorithmic) standpoint but also "from a theoretical perspective. There are two general ideas, namely "finite differences" and "finite element", involved in solving all kinds of these equations. It is decided to use only the finite differences, for their simplicity and comprehensiveness, in the investigation of the solution to the "parabolice" variety of these equations, which in turn entail more diverse methods such as "explicit" and "implicit" approaches, before finally comparing and contrasting these methods from the point of view of accuracy, time of application, and writing a computer program.

Ammonolysis of Ethylenedichloride (EDC) in aqueous phase has been studied through a batch process. The reaction is carried out in lL pressure reactor. Previous works have shown that temperature, reaction time, ammonia concentration and molar ratio of reactants can influence the composition of the products. Ethylenediamine (EDA) is the main product and Diethylenetriamine (DETA) cyclic derivatives such as diethylenediamine (PIP) and higher polyamines are by products of the reaction. In the present work comprehensive study is done to determine the effects of above mentioned factors on the relative " yield of polyamines. The analysis of complex mixture of ethyleneamines have been done in optimum conditions by gas-liquid chromatography technique.

Studies have been performed on the production of cellulosic enzymes of Aspergillus niger and Trichoderma reesei with solid-state fermentation technique. The fungi strains were grown on a mineral medium suitable for cellulolytic microorganisms. Three different carbon sources (Cellulosic material) and time hydrolysis were used in order to determine the best condition for cellulase production and more suitable strain. The result indicated that A. niger was more capable enzyme producer with the rice straw. Fermentation with,mixed cuture was also examined. In comparison with one strain, time of maximum yield was reduced. For two fungi enzyme activity was reduced with increasing of hydrolyzingtime.

We study the behaviour of the ideal fermi gas in the harmonic potential, to calculate the Landau dimagnetism and the magnetic susceptibility in the Non - Commutative Space. We define a parameter K to distinguish Landau diamagnetism in usual space and in the non - commutative space. By calculating the susceptibility we find out that under the condition that k--- > 0 the susceptibility in two different spaces gives similar results.

Microbiological influenced corrosion (MIC) is a type of corrosion in that microorganisms accelerates the chemical corrosion in metal equipments and pipelines. MIC in power units is detected by observations and microbial culturing. In this search a MIC study were done in two power units of Iran by precision observations of differentpartsand severalmicrobialcultures. For this purpose, circulating systems of water and distilled water, turbins, fire system and basins were exactly examined with direct observations, microscopic examinations and culturing. In direct observations, Pipeline Lickages, coupons evaluations, by-passed pipes, deposites, bioaccumulations in pipes and cooling towers, decomposion form of metal and non-metal equipments were examined precisionaly. Culturing methods were done with collection of samples (by Sterile bottles), and inoculation of then in APB, TBC and SRB cultural media After incubation period, results were matched with observations. Results revealed that the MIC was the important (or the main, in several items) causative agent in decomposion, corrosion and Lickages, plugging of pIpelines and finally trip of the unit. Those phonemenons were observed clearly in the internal parts of condensors and pumps. Bio accumulations and microbial attack were caused decreases the efficiency of pumps, plugging and likages of condensers. In this way trip of the units initially were occurred by entrance of industrial water in to distilled water system (caused by lickage of condensers).MIC and accumulated deposites in all points of circulating water system, cause decrease of water flow and ewsulted in decrease of power production. The best methods for control of MIC is a collection of chemical and mechanical methods with routin microbial tests.

In this paper formulation of a paint (DYE) which can resists the rough weather condition (containing the water) has been proposed. This types of DYE can be useful for coating metal in port. Ship structure, oil vessels, it can be used in generally for all, positions and locations which is in clouding corrosion, rough weather conditions. In this cases additive materials and prime matters the DYE conditions shifted toward to a perfectly meet the project needs. The riched cine (coaned = inc) is such a two component dye based on resin epoxy poly amid, the second compound which is the strengthener which the last part broug it as the catalyst.And dryness of the film of the paint which has been responsible for hard duties.