时间分辨-窗口技术应用研究(Ⅲ)——时间分辨荧光光谱法同时测定铽和镝

研究了Tb~(3+)、Dy~(3+)-乙酰丙酮(AA)-三正辛基氧化膦(TOPO)-Triton X-100体系的荧光特性,利用时间分辨-窗口技术实现了Tb和Dy的同时测定,用于合成样品和氧化钇试剂中痕量Tb、Dy的测定,结果良好。     

Numerical integration for the real time production of fundamental ephemerides over a wide time span

A simplified model of the solar system has been developed along with an integration method, enabling to compute planetary and lunar ephemerides to an accuracy better than 1 and 2 milliarcsecs, respectively. On current personal computers, the integration procedure (SOLEX) is fast enough that by using a relatively small ( 20 Kbytes/Cy) database of starting conditions, any epoch in the time interval (up to ±100 Cy) covered by the database can be reached by the integrator in a few seconds. This makes the algorithm convenient for the direct computation of high precision ephemerides over a time span of several millennia.     

A real time processing system of seismic waves using personal computers — Function and characteristics

Conclusions The real-time processing system of CTSN performs following: A/D conversion; automatic event detection; event data saving; automatic measure of P and S arrivals; event location and print out the calculated results. It is corrected at ny moment by using the off-line system. Since December 1993, this system has been operating normally in the CTSN. More than 4 000 earthquakes have been recorded in the system. It has high accuracy in automatic picking P and S arrivals. The location of the earthquakes determined by on-line system are close to those given in published catalogues which are determined by manual procedure. This system can finish locate event in three minutes. It also gives satisfactory epicenter locations for distant events by inputting manually S arrivals in the off-line system. The operation of this system had brought the technical superiority of the CTSN. It not only reduces the labor intensity and simplifies the working procedure, but also makes our research facility into the superior ranks in this field of our country. In conclusion, the real-time processing system of seismic wave provides technical support for the daily requirements of monitoring seismic activity as well as a lot of digital waveform data used seismic research in Sichuan area. This subject is sponsored by the Scientific and Technical Committee of Sichuan Province.     

人工神经网络萃取光度法同时测定金,铂,钯

采用人工神经网络中的Ｂ－Ｐ算法对同时测定贵金属元素金、铂、钯的显色体系进行了研究,２－巯基苯骈噻唑（ＭＢＴ）为显色剂,碘化钾、二氯化锡为辅助络合剂,甲基异丁酮为萃取剂。结果表明,人工神经网络对于处理非线性数据具有很强的校正功能,利用该体系进行多组分同时测定相对误差可控制在±３％,合成样品测定结果令人满意。     

一种黄金密度的测定方法

分析了用阿基米德方法测定金块密度时影响准确度的３个因素,即不同温度下水密度的影响及其校正放置金块吊篮的影响及校正以及天平感量与测定误差间的关系。     

Determination of Iodine in Thirty Two International Geochemical Reference Materials

Thirty two geochemical reference samples have been analysed for their iodine contents by a pyrohydrolysis extraction technique, followed by colourimetry. In spite of the existence of few reported values for iodine, limiting comparison with results from this study, the four available "reference" values show good agreement with the work reported here.     

大行星位置测定的现状

大行星位置的测定是天体测量和天体力学中一项长期而重要的任务。本文介绍了测定大行星位置的意义,重点概括了大行星位置测定的现状,最后讨论了高精度测定外行星位置的困难及今后努力的方向。     

ORBIT OF THE BOWHEAD WHALE, BAIAENA MYSTICETUS

INTRODUCTIONThehoweadwhales(Bahaamyticeus)areveryiInPOrtantsPeciesinthetraditionandctiltmeoftheEskimoPeoPle,whohuntthemeveryyear,andhaveagredtoallowsomesPecimenstobecollectedfromharVested(forsubsistence)boweadwhalesforscien-tificresearehpUrpOses.StudiesontheothitofthebOweadwhalearefewandfarbetWeen.unanisANDMrmODTheorbitsofttheboweadwhaleskulls(87B6,9oB11,94B12)keptinNorthSlopeBorough,Barrow,Alaska,U.S.A.lwereobservedinsitu.asSULrsTheorbitisacavitywhichenclosestheeyeball,witht…     

地质年代在银河年中的周期规律

地质年代表中,从震旦纪至第三纪,各个纪之间的时间间隔并不是均匀相等的。根据天文学家观测到的银河系中心（银心）的赤道座标位置,确定出太阳系在银道面上的位置,把太阳系及地球绕银河系中心公转一周的时间确定为二亿二千万年。以目前太阳系在银道面上的位置为起点,按照时间倒退,顺时针逆转做图,确定过去不同地质年代太阳系在银道面上的位置。可以发现白垩、石炭、寒武、早震旦这四个纪,第三、二叠、奥陶这三个纪,三叠、志留、晚震旦这三个纪,侏罗、泥盆这二个纪各分别发生在银道面的同一位置。