فهرست مطالب v. jafari

Blasting is the initial stage of development in mining operations. Therefore, the use of explosives requires a technical design to control its adverse effects on nearby structures. In that regard, the blast vibrations in Izeh-Karun 3 main road project were recorded using four 3-component Blast Recorder seismographs. The seismographs recorded a peak particle velocity of 8.8 mm/sec in the nearby oil pipe. The blast pattern and the resulting ground vibration are simulated. The numerical model is verified using the recorded seismic data and the empirical model. The stresses applied on the oil pipeline were measured by the static analysis of the stress induced by the oil pipeline's internal pressure and the dynamic analysis of ground vibration. The pipeline stress was equal to 271 MPa, lower than the pipeline yield stress (414 MPa). Therefore, the vibrations induced by the blasting operation did not damage the oil pipeline. Comparing the vibration induced in the oil pipeline (8.8 mm/sec) with the critical vibration level (50 mm/sec) showed that the pipelines near the blast operation were at a safe distance.

This study was conducted to evaluate the effect of aqueous Zingiber officinale extract (ZE) on growth performance, antioxidant activity and resistance of shrimp (Litopenaeus vannamei) challenged with Photobacterium damselae bacteria. A total number of 600 post larvae shrimps (initial weight, 1.06±0.7 g) were randomly distributed into 12 fiberglass tanks representing four treatments each tank containing of 50 shrimp. The control shrimp group (ZE0) was fed a ZE free basal diet. Other groups were fed the basal diet supplemented with 0.5 (ZE 0.5), 1.0 (ZE1) and 1.5 (ZE 1.5) g kg-1 diet. Diets were offered to shrimp at a feeding rate of 10% of live body weight for 8 weeks. After 8 weeks of experimental trial 30 shrimp from each group was infected with LD70 bacteria P. damselae over 10 days to evaluated disease resistance of infected shrimp. Results revealed that growth performance (WG, SGR, FW and PER), the antioxidant activity (SOD, PO, GPx and CAT) of shrimp have significantly increased and cumulative mortality rate decreased (p<0.05) in the ZE1 group compared with the other groups. Meanwhile, the lowest FCR and MDA value were observed in shrimp fed ZE1 supplemented diet. It can be concluded that Z. officinale extract at the level of 1g kg-1 (ZE1) diet seems to be the most appropriate level for increasing growth performance, antioxidant activity and disease resistance of L. vannamei.

Starvation periods of fish in during the developmental stages on growth indices and blood factors can be affected. The effects of compensatory growth on growth indices and physiological responses (glucose, total protein and cholesterol), study for 8 week investigated in Juveniles of common carp (Cyprinus carpio). The fish were divided in 4 experimental groups with initial weight (13/88±0/88 gr) in triplicate that included: 0 (T1) 2 days (T2), 4 days (T3) and a week (T4) starvation and refeeding periods each with 3 replicates were suffered. At the end of testing blood samples for biochemical analysis of each of the treatments used and metabolites were measured by spectrophotometry methode. Results showed growth indices including the final weight, growth rate, specific growth rate and body weight gain in the control and treatment 2 days a week of starvation were significantly different (p<0.05) but between treatments 1 day starvation and control there was no significant difference (p>0.05). The condition factor and feed conversion ratio in all treatments no significant difference (p>0.05). glucose levels between treatment starvation and control groups showed significant differences (p<0.05) but the total protein and cholesterol were not significantly different between control and starved treatments (p>0.05). The results suggest that commomcarp has the physiologic adjustment ability to short-term starvation and re-feeding period.