To satisfy the requirements of nuclear reaction cross sections in nuclear engineering applications and nuclear physics studies,the Neutron Activation Cross Section Data Library has been established.818 target nuclei i...To satisfy the requirements of nuclear reaction cross sections in nuclear engineering applications and nuclear physics studies,the Neutron Activation Cross Section Data Library has been established.818 target nuclei including unstable target or isomeric target nuclei are considered in this library.The induced neutron energy range region is between 10^(-5)eV and 20 MeV.The standard ENDF-6 format is adopted,including general information,reaction cross sections,multiplicities,and so on.The recommended reaction cross sections were obtained using UNF code system and FDRR nuclear model codes or systematic analysis based on available experimental data.展开更多
A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temp...A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen（DO） on cold active lipase production by batch culture of metagenomic library recombinant clone（CAPL3） from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 ℃ for the first 15 h, and then switched to30 ℃. The cold active lipase activity and productivity reached 315.2 U·ml^-1and 8.08 U·ml^-1·h^-1, respectively,increased by both 14.5% compared to the results obtained with temperature controlled at 30℃. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34℃, 30% during 0–15 h;30 ℃, 30% during 15–18 h, and 30 ℃, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml^-1at 39 h, which was 28.8% higher than that achieved without temperature and DO control（275.3 U·ml^-1）.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 11934004 and U1832201)the Science Challenge Project (Grant No. TZ2016005)the CAEP Foundation (Grant No. CX2019022)
文摘To satisfy the requirements of nuclear reaction cross sections in nuclear engineering applications and nuclear physics studies,the Neutron Activation Cross Section Data Library has been established.818 target nuclei including unstable target or isomeric target nuclei are considered in this library.The induced neutron energy range region is between 10^(-5)eV and 20 MeV.The standard ENDF-6 format is adopted,including general information,reaction cross sections,multiplicities,and so on.The recommended reaction cross sections were obtained using UNF code system and FDRR nuclear model codes or systematic analysis based on available experimental data.
基金Supported by the Hi-Tech Research and Development Program of China(863 program of China2012AA092103)China Ocean Mineral Resources R&D Association(DY125-15-T-06)
文摘A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen（DO） on cold active lipase production by batch culture of metagenomic library recombinant clone（CAPL3） from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 ℃ for the first 15 h, and then switched to30 ℃. The cold active lipase activity and productivity reached 315.2 U·ml^-1and 8.08 U·ml^-1·h^-1, respectively,increased by both 14.5% compared to the results obtained with temperature controlled at 30℃. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34℃, 30% during 0–15 h;30 ℃, 30% during 15–18 h, and 30 ℃, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml^-1at 39 h, which was 28.8% higher than that achieved without temperature and DO control（275.3 U·ml^-1）.
