[Design, production and evaluation of electronic hook for mice population controlling]

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. 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 commands which is sent to electrical bobbins evaluates. Later, the middle 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. 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. 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 current methods 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

Treatment of wastewater in plating industry by chelate extraction method

One of the most efficient methods to preserve environment is the procedure and method to achieve effective materials and the dual and reapplication of natural sources. In this research, After carrying out a vast study on the growing spot of Iranian oaks, of the 36 species and subspecies already identified, 10 species and subspecies were selected as they cover a vaster surface of Iranian woods in North Alborz Region, Arsabaran region and the western part of Zagros Mountains. 5 samples were collected of each type form different spots of the country. The effective and usable substances of oak fruit were extracted and isolated by the four methods of maceration, decoction, perculation and soxhlet tannin in one specie show no significant difference; However the amount of tannin in different species show significant differences in statistical term in such a way that the minimum and maximum tannin was found in Q.Brantii, Belangri with 9.7% tannin and Q.Macrantera, with 3.2 percent tannin. This amount was put in contact with wastewater various from plating industries in 20 to 50 mg/L amount. The mentioned wastewaters contained 50 to 750 mg/L heavy metals [chromium, nickel, zinc, copper and silver]. The results were analyzed through a biofactor variance analysis model with repetition in each house [Toki] Results showed that the removal output for zinc, copper, nickel and chromium without considering the initial concentration of the metal were 91 to 95 percent, 71 to 83.5 percent, 59 to 90 percent, and 84 to 85 percent, respectively. Also, with respect to the studies carried out with different methods and comparing the percentage of metals removal it was concluded that the removals output through applying 50 mg/L. hydroxide calcium along with 50 mg/L tannin with 82.3 percent average had the most effects in entire metals