Natural Se element have six kinds of isotope ^74Se, ^76Se, ^77Se, ^78Se, ^80Se and ^82Se,and the natural content of ^74Se is 0. 87%. After being shot by neutron, ^78Se isotope can be changed to be short decayed period...Natural Se element have six kinds of isotope ^74Se, ^76Se, ^77Se, ^78Se, ^80Se and ^82Se,and the natural content of ^74Se is 0. 87%. After being shot by neutron, ^78Se isotope can be changed to be short decayed period to radioisotope. The radiation source made up fro mhigh density ^75Se isotope, which content is more than 90%, is quite valuable for application of agriculture and nuclear medical science and such aspect. This study mainly presents experimental research on gas mass spectrograph, establishes the analysis method for isotope content of Se F6, gives best temperature needed to eradicate impurity from sample,relative strength of Se F6 fragment ion summit under the best electron energy, characteristic summit and data processing technique etc. Using this method, the measuring accuracy of ^74Se isotope content of natural Se F6 is 0.4%. The technique can also be applied to examine products.展开更多
O432.1 2000020752实现光辐射度量基准的几种方法=A few physicalmethods for realizing photometric primary standard[刊,中]/孙立群,朱京平,唐天同,(西安交通大学电子与信息工程学院.陕西,西安(710049)),张玫(西安应用光学研究所.陕...O432.1 2000020752实现光辐射度量基准的几种方法=A few physicalmethods for realizing photometric primary standard[刊,中]/孙立群,朱京平,唐天同,(西安交通大学电子与信息工程学院.陕西,西安(710049)),张玫(西安应用光学研究所.陕西,西安(710065))//应用光学.-1999,20(2).-36-39总结了实现光辐射度量基准的几种主要方法,包括黑体辐射器法,电替代绝对辐射计法,自校准硅光电二极管法和光电探测器量子效率绝对测量法,并对各种方法的优缺点进行比较。图3参5(吴淑珍)展开更多
文摘Natural Se element have six kinds of isotope ^74Se, ^76Se, ^77Se, ^78Se, ^80Se and ^82Se,and the natural content of ^74Se is 0. 87%. After being shot by neutron, ^78Se isotope can be changed to be short decayed period to radioisotope. The radiation source made up fro mhigh density ^75Se isotope, which content is more than 90%, is quite valuable for application of agriculture and nuclear medical science and such aspect. This study mainly presents experimental research on gas mass spectrograph, establishes the analysis method for isotope content of Se F6, gives best temperature needed to eradicate impurity from sample,relative strength of Se F6 fragment ion summit under the best electron energy, characteristic summit and data processing technique etc. Using this method, the measuring accuracy of ^74Se isotope content of natural Se F6 is 0.4%. The technique can also be applied to examine products.
文摘O432.1 2000020752实现光辐射度量基准的几种方法=A few physicalmethods for realizing photometric primary standard[刊,中]/孙立群,朱京平,唐天同,(西安交通大学电子与信息工程学院.陕西,西安(710049)),张玫(西安应用光学研究所.陕西,西安(710065))//应用光学.-1999,20(2).-36-39总结了实现光辐射度量基准的几种主要方法,包括黑体辐射器法,电替代绝对辐射计法,自校准硅光电二极管法和光电探测器量子效率绝对测量法,并对各种方法的优缺点进行比较。图3参5(吴淑珍)