Iranian Journal of

Backgrounds and Objectives:since large cities of Iran due to specific population, topographic, cultural and economical conditions have a numerous population per surface unit, , results in everincreasing population and it.s accumulation and have prepared favorable conditions for increasing various mice and rats species in these cities. Efforts, designing, construction and evaluation of electronic traps for mouse and rat controlling is one of the controlling methods which may be studied beside the other methods.
Materials and Methods:At first the types and species of mice and rats in Tehran city were studied (including length, weight, behavior characteristics etc.). Next, using a system producing attractive fragrance attracts mouse and rat to the trap. Then, using electronic sensors, mouse presence with commandswhich is sent to electrical bobbins evaluates.Later, themiddle section becomes electrically activated. Contacting the trap, the animal will die within 3 to 5 seconds contacting. Mouse corpse will transfer to the beneath section of trap. This section includes a drawer to be emptied daily or weekly. Preventing electric shocks, the power of all the sections will go with drawing out the drawer. Testing efficiency of the device, it was tried first with lab mice thus in each level of experiences the problems were solved.
Results:According to the design, each section of the device including attraction, killing and removing sections were evaluated separately. For instance, in killing section, the amount of voltage and its type also the method of electricity transfer to the animal was evaluated. In addition in attraction section the variety of fragrances were compared and it was found that walnut fragrance gave the best result for all the animal samples attraction. Also, the results showed 300 volts current voltage with 15 Amperes current intensity, has the best killing efficiency in less than a second than other voltages.
Conclusion:According to the different evaluations, it was clear there were no good results of killing in 2.5 to 15Amperes direct current intensity. Thus using direct currentmethods in these trap devices were not practical. In addition, using sexual fragrances for attraction males, in several species were tested and results showed that the proteins in these fragrances became decomposed very fast in environmental conditions and the attraction nature of these substances decreased. For this reason it seams according to its easy availability, food fragrances as attraction substances are more practical and useful.

Backgrounds and Objectives: Reactive dyestuff has potential of toxicity, carcinogenesis and mutagenesis for mammals and aquatic organisms. The current physical and chemical methods such as adsorption, coagulation, precipitation, filtration and ... can been used for removing of dyestuff. Biological treatment which is effective and economic for decontamination of dyestuff wastewaters was preferred because of limitation and difficulty of physicochemical methods. In order to investigate the trend of pollution reduction of color compounds, ability of Remazol Black-B dyestuff removal from aqueous medium by bacterial consortium under anoxic conditions was studied.
Materials and Methods: The mix culture of bacteria from textile industries activated sludge was enriched in luria broth medium containing RB-B dyestuff as a carbon source. Then biodegradation was assessed in 4 batch reactors. Microbial population of bacterial and decolorization quantities of samples were detected by MPN and UV-Vis spectrophotometer.
Results: Decolorization efficiency by the bacterial consortium was obtained more than 99% for 50 and 250 mg/L concentrations in 72 and 144 h (3 and 6 days) respectively, while for the initial concentration of 500 mg/L was 98.1in 240 h (10 days) of biodegradation period. Dyestuff reduction rate after completed removal was about 0.69, 1.74,2 mg/L/h for initial concentration of 50, 250, 500 mg/L respectively.
Conclusion: Results showed that Alcaligenes denitrificans and Alcaligenes xylosoxidans bacteria
which were isolated from activated sludge have good potential of RB-B dyestuff removal and this removal is depending on primary concentration of dye. Removal efficiency increased as primary concentration went up.