A new linear integration was developed. First, effective strain rate for slab forging with bulge was expressed in terms of two-dimensional strain rate vector, and its inner-product was integrated term by term. Second,...A new linear integration was developed. First, effective strain rate for slab forging with bulge was expressed in terms of two-dimensional strain rate vector, and its inner-product was integrated term by term. Second, a summation process of term by term integrated results and a formula of the bulging were introduced, and an analytical solution of stress effective factor was obtained. It is proved that the expression of power by the above linear integration is the same as that of traditional immediate integration. Also, the solution was simplified by series expansion and compared by slab forging test with the others. It turns out that the calculated result of total forging pressure is basically in agreement with measured value in the actual press test.展开更多
A new linear integration for plastic power was proposed.The effective strain rate for disk forging with bulge was expressed in terms of two-dimensional strain rate vector,and then its direction cosines were determined...A new linear integration for plastic power was proposed.The effective strain rate for disk forging with bulge was expressed in terms of two-dimensional strain rate vector,and then its direction cosines were determined by the ratio of coordinate increments.Furthermore,inner-product of the vector for plastic power was term integrated by term and summed.Thereafter,through a formula for determination of bulge an analytical solution of stress effective factor was obtained.Finally,through compression tests,the calculated results of above formula were compared with those of Avitzur’s approximate solution and total indicator readings of the testing machine.It is indicated that the calculated compression forces are basically in agreement with the measured ones if the pass reduction is less than 13.35%.However,when the reduction gets up to 25.34% and 33.12%,the corresponding errors between the calculated and measured results also get up to 6% and 13.5%,respectively.展开更多
The yeast Pichia pastoris(P. pastoris) has been used for the expression of heterologous proteins with the significant success. However, it is time-consuming to screen the high expression level of the recombinant P. pa...The yeast Pichia pastoris(P. pastoris) has been used for the expression of heterologous proteins with the significant success. However, it is time-consuming to screen the high expression level of the recombinant P. pastoris directly. Thus, for β-mannanase production, developing the accurate, rapid and inexpensive screening method to substitute random screening is certainly required. A simple method based on the size of hydrolysis hole was described here, but this method was not very accurate that could only be used in preliminary screening. To further improve the accuracy, a micro-plate screening method is established, which appears to be more accurate and effective. The efficiency of this screening method is about 10 times higher than that of the general screening strategy of cultivation in shaking flasks. Two methods presented here can also be used for screening of recombinant Pichia strains with high-level expression of other heterologous protein after modification.展开更多
近五年随着消费者对“天然、绿色、安全”化妆品的关注度日益提高,发酵源化妆品的开发得到了长足发展。对于发酵源化妆品原料的开发,中外研究人员从不同角度入手,提高了相关发酵产物的活性、产量以及有效成分的含量。文章基于中国知网(C...近五年随着消费者对“天然、绿色、安全”化妆品的关注度日益提高,发酵源化妆品的开发得到了长足发展。对于发酵源化妆品原料的开发,中外研究人员从不同角度入手,提高了相关发酵产物的活性、产量以及有效成分的含量。文章基于中国知网(CNKI)数据库以及Web of Science核心数据库,借助文献计量方法和知识图谱可视化软件VOSviewer,以“化妆品”、“发酵”、“cosmetic”、“fermentation”或“fermented”为关键词构建近五年发酵源化妆品文献库,根据可视化分析知识图谱中的关键词共现频率分析近期发酵源化妆品领域的研究热点,并对目前化妆品相关的发酵菌种、发酵产物及功效宣称进行了汇总分析,同时对未来发酵源化妆品的发展与研发提出展望,为发酵源化妆品领域研究提供理论基础。展开更多
文摘A new linear integration was developed. First, effective strain rate for slab forging with bulge was expressed in terms of two-dimensional strain rate vector, and its inner-product was integrated term by term. Second, a summation process of term by term integrated results and a formula of the bulging were introduced, and an analytical solution of stress effective factor was obtained. It is proved that the expression of power by the above linear integration is the same as that of traditional immediate integration. Also, the solution was simplified by series expansion and compared by slab forging test with the others. It turns out that the calculated result of total forging pressure is basically in agreement with measured value in the actual press test.
基金Project(50474015) supported by the National Natural Science Foundation of China
文摘A new linear integration for plastic power was proposed.The effective strain rate for disk forging with bulge was expressed in terms of two-dimensional strain rate vector,and then its direction cosines were determined by the ratio of coordinate increments.Furthermore,inner-product of the vector for plastic power was term integrated by term and summed.Thereafter,through a formula for determination of bulge an analytical solution of stress effective factor was obtained.Finally,through compression tests,the calculated results of above formula were compared with those of Avitzur’s approximate solution and total indicator readings of the testing machine.It is indicated that the calculated compression forces are basically in agreement with the measured ones if the pass reduction is less than 13.35%.However,when the reduction gets up to 25.34% and 33.12%,the corresponding errors between the calculated and measured results also get up to 6% and 13.5%,respectively.
基金Project(CX2012B124)supported by the Graduate Degree Thesis Innovation Program of Hunan ProvinceChina+3 种基金Project(13JJ9002)supported by the Natural Science Foundation of Hunan ProvinceChinaProject(2012XK4081)supported by the Key Science and Technology Plan of Hunan Provincial Science&Technology DepartmentChina
文摘The yeast Pichia pastoris(P. pastoris) has been used for the expression of heterologous proteins with the significant success. However, it is time-consuming to screen the high expression level of the recombinant P. pastoris directly. Thus, for β-mannanase production, developing the accurate, rapid and inexpensive screening method to substitute random screening is certainly required. A simple method based on the size of hydrolysis hole was described here, but this method was not very accurate that could only be used in preliminary screening. To further improve the accuracy, a micro-plate screening method is established, which appears to be more accurate and effective. The efficiency of this screening method is about 10 times higher than that of the general screening strategy of cultivation in shaking flasks. Two methods presented here can also be used for screening of recombinant Pichia strains with high-level expression of other heterologous protein after modification.
文摘近五年随着消费者对“天然、绿色、安全”化妆品的关注度日益提高,发酵源化妆品的开发得到了长足发展。对于发酵源化妆品原料的开发,中外研究人员从不同角度入手,提高了相关发酵产物的活性、产量以及有效成分的含量。文章基于中国知网(CNKI)数据库以及Web of Science核心数据库,借助文献计量方法和知识图谱可视化软件VOSviewer,以“化妆品”、“发酵”、“cosmetic”、“fermentation”或“fermented”为关键词构建近五年发酵源化妆品文献库,根据可视化分析知识图谱中的关键词共现频率分析近期发酵源化妆品领域的研究热点,并对目前化妆品相关的发酵菌种、发酵产物及功效宣称进行了汇总分析,同时对未来发酵源化妆品的发展与研发提出展望,为发酵源化妆品领域研究提供理论基础。
