The impacte of the use different sources of oil on the growth performance fingerling of common carp (Cyprinus carpio L.)

This study was conducted to determine the influence of oil sources on growth performance of fish common carp Cyprinus carpio. Four diets were formed which similar in their protein content and contains four different sources of oil which [Corn oil (A), palm oil (B), sunflower oil (C) and fish oil (D)] 64 fish average weight ranged between (1.598 - 1.544) g were distributed randomly on eight plastic circular form basins with capacity of 20 liters of water. Feeding fish have been tested diets on the rate of 5 % of body weight by repeating each treatment for a period of 42 days. The results showed that there is no significant difference between the treatments (p>0.05) in the values of the final weight, specific growth rate, relative growth rate and food conversion rate. As the weight increase was no significant differences (p>0.05) between treatments (A, B, C), the treatment D (fish oil) was better than treatments (B, A) with significant difference (p<0.05) and did not different

Double-Slope Solar Still Productivity Based on the Number of Rubber Scraper Motions

In low-latitude areas less than 10° in latitude angle, the solar radiation that goes into the solar still increases as the cover slope approaches the latitude angle. However, the amount of water that is condensed and then falls toward the solar-still basin is also increased in this case. Consequently, the solar yield still is significantly decreased, and the accuracy of the prediction method is affected. This reduction in the yield and the accuracy of the prediction method is inversely proportional to the time in which the condensed water stays on the inner side of the condensing cover without collection because more drops will fall down into the basin of the solar-still. Different numbers of scraper motions per hour (NSM), that is, 1, 2, 3, 4, 5, 6, and 7, are implemented to increase the hourly yield of solar still (HYSS) of the double-slope solar still hybrid with rubber scrapers (DSSSHS) in areas at low latitudes and develop an accurate model for forecasting the HYSS. The proposed model is developed by determining the best values of the constant factors that are associated with NSM, and the optimal values of exponent (n) and the unknown constant (C) for the Nusselt number expression (Nu). These variables are used in formulating the models for estimating HYSS. The particle swarm optimization (PSO) algorithm is used to solve the optimization problem, thereby determining the optimal yields. Water that condensed and accumulated inside the condensing glass cover of the DSSSHS is collected by increasing NSM. This process increases in the specific productivity of DSSSHS and the accuracy of the HYSS prediction model. Results show that the proposed model can consistently and accurately estimate HYSS. Based on the relative root mean square error (RRMSE), the proposed model PSO–HYSS attained a minimum value (2.81), whereas the validation models attained Dunkle’s (78.68) and Kumar and Tiwari’s (141.37)