随着中国对虾(Penaeus orientalis Kishinouye)人工育苗技木的突破,我国对虾苗种生产量逐年递增,保证了养殖和增殖放流的需要。但是各育苗场的育苗效果差异较大:好者,平均每尾亲虾可培育十几万尾虾苗;差者,用数万尾亲虾,育苗量甚少。其...随着中国对虾(Penaeus orientalis Kishinouye)人工育苗技木的突破,我国对虾苗种生产量逐年递增,保证了养殖和增殖放流的需要。但是各育苗场的育苗效果差异较大:好者,平均每尾亲虾可培育十几万尾虾苗;差者,用数万尾亲虾,育苗量甚少。其中原因之一是亲虾产卵率低。展开更多
In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassit...In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassiterite particles and H2 bubbles was explored.The flotation tests were carried out in a single bubble flotation cell.The results show that cassiterite particles 10 μm,10-20 μm,20？38 μm and 38-74 μm match with bubbles with size of 50-150 μm,about 250 μm,74 μm and 74 μm,respectively,and a better recovery can be obtained.It is demonstrated that the recovery of cassiterite is influenced by the size of cassiterite particles and bubbles.Furthermore,the probabilities of collision,adhesion,detachment and collection were calculated using the collision,attachment and collection models.Theoretical calculation results show that the collision probability decreases sharply with decreasing particle size and increasing bubble size（below 150 μm）.The attachment probability would increase from the effective collision,leading to the increase of recovery.展开更多
In order to improve the in vitro fertilization rate of bovine, the effects of different sperm capacitation methods on fertilization were investigated. Total two treatments were designed： two-time centrifugation （C）...In order to improve the in vitro fertilization rate of bovine, the effects of different sperm capacitation methods on fertilization were investigated. Total two treatments were designed： two-time centrifugation （C）, and one-time centrifugation and swim-up method （CS）. The results showed that the cleavage rate in the C treatment group was （75.6±4.5）%, which showed no difference compared with that （（76.4±1.9）%） in the CS treatment group （P〉0.05）; there was also no significant dif- ference in blastocyst rate between the two treatment groups （（35.7±4.1）% vs. （36.3± 2.7）%, P〉0.05）. However, the CS treatment significantly saved the capacitation time in vitro.展开更多
This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stag...This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stage,influence of pH,solid concentration,water chemistry and the amount of collector dosage were investigated on kinetics parameters including flotation rate constant and ultimate recovery.The results indicated that that perfectly mixed reactor model and Kelsall model gave the best and the weakest fit to the experimental data,respectively.It was observed that flotation rate constant and ultimate recovery were strongly affected by chemical factors investigated especially water quality.The flotation rate constant decreased with increasing the solids content,while ultimate recovery increased to certain value and thereafter reduced.It was also found that the most values of flotation rate constant and ultimate recovery obtained in dosage of collector are 30 and 40 g/t,respectively.展开更多
基金Project(50774094)supported by the National Natural Science Foundation of ChinaProject(2010CB630905)supported by the National Basic Research Program of China
文摘In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassiterite particles and H2 bubbles was explored.The flotation tests were carried out in a single bubble flotation cell.The results show that cassiterite particles 10 μm,10-20 μm,20？38 μm and 38-74 μm match with bubbles with size of 50-150 μm,about 250 μm,74 μm and 74 μm,respectively,and a better recovery can be obtained.It is demonstrated that the recovery of cassiterite is influenced by the size of cassiterite particles and bubbles.Furthermore,the probabilities of collision,adhesion,detachment and collection were calculated using the collision,attachment and collection models.Theoretical calculation results show that the collision probability decreases sharply with decreasing particle size and increasing bubble size（below 150 μm）.The attachment probability would increase from the effective collision,leading to the increase of recovery.
基金Supported by Earmarked Fund for China Agriculture(Beef and Yak)Research System(NYCYTX-38)Key Agriculture Research and Development Program of Qiqihar(NYGG-201524)~~
文摘In order to improve the in vitro fertilization rate of bovine, the effects of different sperm capacitation methods on fertilization were investigated. Total two treatments were designed： two-time centrifugation （C）, and one-time centrifugation and swim-up method （CS）. The results showed that the cleavage rate in the C treatment group was （75.6±4.5）%, which showed no difference compared with that （（76.4±1.9）%） in the CS treatment group （P〉0.05）; there was also no significant dif- ference in blastocyst rate between the two treatment groups （（35.7±4.1）% vs. （36.3± 2.7）%, P〉0.05）. However, the CS treatment significantly saved the capacitation time in vitro.
文摘This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stage,influence of pH,solid concentration,water chemistry and the amount of collector dosage were investigated on kinetics parameters including flotation rate constant and ultimate recovery.The results indicated that that perfectly mixed reactor model and Kelsall model gave the best and the weakest fit to the experimental data,respectively.It was observed that flotation rate constant and ultimate recovery were strongly affected by chemical factors investigated especially water quality.The flotation rate constant decreased with increasing the solids content,while ultimate recovery increased to certain value and thereafter reduced.It was also found that the most values of flotation rate constant and ultimate recovery obtained in dosage of collector are 30 and 40 g/t,respectively.
