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Shahrechay Dam is located at 12^th Km of Shahrechay River in Urmia. This study was conducted for a year (Spring to fall, 2007) to identify different species of benthic organisms in the dam. Considering the relevant topographic status like the local depth and water speed, 6 sampling stations were chosen and sampling was done in shallow locations of the river by means of superficial method. In this study, 2 phylums, 2 orders, 13 families and 21 species of benthic organisms were identified in Shahrechay Dam Lake. The results indicated that the highest species diversity belonged to Ecdyonuridae family (Eperous Genus). In terms of frequency, it belonged to Tibuficidae (Tubifex Genus), with 43%, 23%, and 11% ratios for spring, summer, and fall, respectively. The final result of the research demonstrated the poverty of lake bed from view of the benthic quantity and density. Therefore, the Shahrechay Dam was not a suitable candidate to develop fishery’s purposes, especially releasing and growing Cyprinidae fishes and other benthos-feeder aquatics.

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Selco enriching emulsion includes compounds from certain oils with marine and herbal origins. Selco oil produces micro-globules with less than 0.1 micron diameter. In order to generate such stability in original selco chemical emulsifiers have been used up to 3%. In this study, persian gum )Amygdalus scopariaspeech( and salep (Orchis mascula (were used as herbal emulsifiers in synthesis of Artemia enriching for a content of 11% to establish emulsification. The soluble part of persian gum and salep was separated with 30% and 22% content, respectively. Through chemical analysis, the chemical composition of the imported Selco oil was identified. Then the similar ingredients of the commercial brand were combined to produce our synthesized production. In physical computing, the average diameter and distribution of oil phase particles side was obtained as 0.1 micron and the relevant surface tension as 15±5 DIN/cm. Then the synthesyzed enriching oil (treatment 1) with the imported one (treatment 2) were tested for Artemia urmiana enriching with standard conditions. Enriching conducted in 3 repetitions with 0.4 gr/lit of the enriching oils/1 lit of water. Nauplii were introduced as 200000 nauplii/lit. The average of nauplii enriching percentage in treatments 1 and 2 was achieved as 27±2.47 and 23±2.52 percent, respectively. The bioassay results on 500 new feed larvae of trout fish has been shown that treatments 1 and 2 were significantly differed in survival. Therefore, the plant emulsifiers in this study, showed good performances as the chemical and physical properties, in stabilizing the oil emulsion in the aqueous phase.

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Chitin and chitosan are two very important biopolymer products that have so many usages in the high cost industries. Chitin Converts into chitosan via de-acetylation of chitin. It occurs by alkaline melting method in the absence of oxygen. Chemical structure change, severe environmental pollution and De-polymerization are of the major problems in producing high quality chitosan. In this study for conversion of chitin into chitosan fungus Aspergillus niger strains (ATHUM-10864), the generator of de-acetylases enzymes were used instead of chemicals. Chitosan quality was determined via elemental analysis infrared spectroscopy, X-ray tomography, molecular weight determination and estimation of crystallinity percent, color and molecular structure.The results showed 80±5% efficiency in the conversion of chitin into chitosan or de-acetylation degree of chitin. The gained chitosan contained of 44.4 % carbon, 8.9 % nitrogen, 2.7 % hydrogen and 39.5 % oxygen. The physical characteristics were as 94.5% Crystallinity and pale brown color. The chemical structure of per unit of chitosan was obtained as C6H12NO4. The results showed that replacing biological methods instead of chemicals was possible to access well quality products. It also eliminates the use of chemical materials such as concentrate sodium hydroxide that is damaging the environment.