The microwave-assisted extraction(MAE)technology of tyrosinase inhibitor from batryticated silkworms was studied with the yield and the relative inhibitory activity against tyrosinase(RIAAT) of the extract used as eva...The microwave-assisted extraction(MAE)technology of tyrosinase inhibitor from batryticated silkworms was studied with the yield and the relative inhibitory activity against tyrosinase(RIAAT) of the extract used as evaluating indexes in the experiment.The effects of extraction variables,especially solvent concentrations,microwave power,the duration of microwave irradiation,materials-solvent mass ratio and material particle size on extraction efficiency were investigated.It was concluded that the optimal condition was two doses of microwave radiation(450 W) for 7 min with a mass ratio of 70 % ethanol to material by 8∶1.The extract of batryticated silkworms with 15.8 % yield and 66.7 % RIAAT was obtained after the extracted liquor was decoloured with active char,concentrated and then dried under vacuum.Compared with direct-heating extraction(DHE),MAE can shorten extracting duration,improve the yield and RIAAT of the extract.展开更多
在Bala and Goyal(2000)提出的双向流网络形成模型基础上,研究当个体存在异质性时对纳什网络存在性的影响.分别针对几种不同的环境设定下的个体异质性进行研究,发现个体的连接成本异质性是决定纳什网络存在性的重要因素;但相较于个体的...在Bala and Goyal(2000)提出的双向流网络形成模型基础上,研究当个体存在异质性时对纳什网络存在性的影响.分别针对几种不同的环境设定下的个体异质性进行研究,发现个体的连接成本异质性是决定纳什网络存在性的重要因素;但相较于个体的连接成本而言,连接价值的异质性对纳什网络存在性的影响不大.展开更多
传统给水泵小汽轮机以机组最大出力为选型基准,在机组THA及以下工况运行时小汽轮机运行效率相对下降较多。为提高小汽轮机运行效率,有必要开展给水泵小汽轮机优化选型研究。利用汽轮机补汽增大出力的原理,以机组THA工况对应出力为小汽...传统给水泵小汽轮机以机组最大出力为选型基准,在机组THA及以下工况运行时小汽轮机运行效率相对下降较多。为提高小汽轮机运行效率,有必要开展给水泵小汽轮机优化选型研究。利用汽轮机补汽增大出力的原理,以机组THA工况对应出力为小汽轮机设计选型基准,需要更大出力时通过开启补汽来实现,可相对提高THA及以下工况小汽轮机运行效率。结合某二次再热机组给水泵小汽轮机选型分析实例,对优化前后小汽轮机工作参数进行计算,对比分析不同工况下小汽轮机耗汽量及对机组能耗指标的影响。结果表明,优化选型后,THA、75%THA和50%THA工况下对应小汽轮机进汽流量分别降低1.9、1.2、0.8 t/h,汽轮机热耗分别降低3.08、3.42、3.62 k J/(k W·h)。该小汽轮机优化选型方法可在超超临界二次再热机组上推广应用。展开更多
基金supported by the National Natural Science Foundation of China(51072137,50802064,11074189)Key Projects in the NationalScience&Technology Pillar Program,China(2009BAC62B02)Shanghai Committee of Science and Technology,China(11nm0501600)~~
基金supported by the National Natural Science Foundation of China(51072137,50802064,11074189)Key Projects in the National Science&Technology Pillar Program,China(2009BAC62B02)Shanghai Committee of Science and Technology,China(11nm0501600)~~
文摘The microwave-assisted extraction(MAE)technology of tyrosinase inhibitor from batryticated silkworms was studied with the yield and the relative inhibitory activity against tyrosinase(RIAAT) of the extract used as evaluating indexes in the experiment.The effects of extraction variables,especially solvent concentrations,microwave power,the duration of microwave irradiation,materials-solvent mass ratio and material particle size on extraction efficiency were investigated.It was concluded that the optimal condition was two doses of microwave radiation(450 W) for 7 min with a mass ratio of 70 % ethanol to material by 8∶1.The extract of batryticated silkworms with 15.8 % yield and 66.7 % RIAAT was obtained after the extracted liquor was decoloured with active char,concentrated and then dried under vacuum.Compared with direct-heating extraction(DHE),MAE can shorten extracting duration,improve the yield and RIAAT of the extract.
文摘在Bala and Goyal(2000)提出的双向流网络形成模型基础上,研究当个体存在异质性时对纳什网络存在性的影响.分别针对几种不同的环境设定下的个体异质性进行研究,发现个体的连接成本异质性是决定纳什网络存在性的重要因素;但相较于个体的连接成本而言,连接价值的异质性对纳什网络存在性的影响不大.
文摘传统给水泵小汽轮机以机组最大出力为选型基准,在机组THA及以下工况运行时小汽轮机运行效率相对下降较多。为提高小汽轮机运行效率,有必要开展给水泵小汽轮机优化选型研究。利用汽轮机补汽增大出力的原理,以机组THA工况对应出力为小汽轮机设计选型基准,需要更大出力时通过开启补汽来实现,可相对提高THA及以下工况小汽轮机运行效率。结合某二次再热机组给水泵小汽轮机选型分析实例,对优化前后小汽轮机工作参数进行计算,对比分析不同工况下小汽轮机耗汽量及对机组能耗指标的影响。结果表明,优化选型后,THA、75%THA和50%THA工况下对应小汽轮机进汽流量分别降低1.9、1.2、0.8 t/h,汽轮机热耗分别降低3.08、3.42、3.62 k J/(k W·h)。该小汽轮机优化选型方法可在超超临界二次再热机组上推广应用。
