孕妇缺锰及防治

已测试了12000件孕妇头发微量元素，缺锰最普遍，达65%以上，对孕妇缺锰的防治提出了建议．     

巧用晶体三极管测小电容

在没有电容表的情况下，电容有无容量一般是用万用表的欧姆档大致估测，利用电容的充、放电作用，根据表针摆动角度的大小来估量其容量的大小．但这种方法只适用于容量大于几千pF的电容，当电容容量小于2000PF时，即使使用XIokQ的电阻档，表针也几乎不动，此时就难以判定是电容     

VG 354质谱计离子源电离带低温测量设备及其应用

设计了一种用于VG 354 型热电离质谱计电离带低温测量装置(DWZZ).它由热电偶温度计及连接件组装而成,能即时测定电离带的表面温度.测定的离子源中电离带的低温段温度与加热电流的关系可用关系式y=-ax3+bx2-cx+d表示,温度测定的误差＜±2℃.此装置已用于石墨非还原热离子发射特性和石墨存在下M2BO+2、M2X+离子的发射机理的研究.     

关于百分制考试成绩χ~2检验的注记

魏文元，冯淑芬．关于百分制考试成绩χ２检验的注记，数理统计与管理，１９９７，１６，（１），３５～３８．本文提出“分数正态分布”的χ２检验问题，指出在对学生考分这一特殊总体进行χ２检验时，除了要进行通常的χ２检验外，还要对其样本均值和样本标准差作适当限制，从而使χ２检验法更加完善，更具实际意义     

Radon变换CHD反演方法的稳定化数值方法

本文利用Ｔｉｋｈｏｎｏｖ正则化方法、线性插值给出了Ｒａｄｏｎ变换ＣＨＤ反演方法的稳定化数值方法。克服了Ｒａｄｏｎ变换ＣＨＤ反演方法的不稳定性，且便于计算机实现。     

STUDIES ON BIS(ALKENYLCYCLOPENTADIENYL) IVB GROUP METAL DERIVATIVES

A series of new bis(allyleyclopentadienyl) and bis(2-butenylcyelopentadienyl) dichlorides of titanium, zirconium and hafnium have been synthesized by reacting sodium allyl or 2-butenylcyclopentadienide with IVB group metal chlorides. The substituted bis-cyclopentadienyl metal dichlorides treated with inorganic halides, aryllithium, potassium thiocyanate or hydrogen sulfide, bis(alkenylcyclopentadienyl)metal dihalides, and that of diaryl, dithiocyanato and dimercaptometal derivatives were obtained. Addition reaction on allyl group in bis(allylcyclopentadienyl) dihalides of titanium, zirconium and hafnium with hydrogen halide, halogen was studied. It was found that the addition of HX followed Markovnikov's rule.The reactivity of electrophilic addition increased in the order HCl相似文献   

ADENYLATE CYCLASE-MODULATING MEDIATORS OF INSULIN

Plasma membranes prepared from pig liver incubated with insulin (50—300 μU/ml) resulted in the release of at least two insulin chemical mediators. They appeared to modulate the activity of adenylate cyclase in liver plasma membrances of pig. One of them was fraction 1 of insulin mediator (M. W. about 3700—4000 dalton) which markedly stimulated the activity of the enzyme, the other was fraction 2 of insulin mediator (M. W. about 1000 dalton) which inhibited the enzyme activity. The results showed that the inhibitor of fraction 2 generated was significantly higher than that of fraction 1 when the membranes were incubated with insulin of low concentration (50—100 μU/ml). On the other hand, the generation of stimulator of fraction 1 from plasma membranes incubated with insulin of high concentration (200 μU/ml) was higher than that of fraction 2. So the ratio of yield between two mediators produced from the membranes was dependent on the concentration of insulin added. The results also showed that the     

基于矩阵分裂的广义逆A_（T，S）~（2）的表示及其应用

本文首先给出基于矩阵分裂的广义逆Ａ_（Ｔ，Ｓ）~（２）的表示，并将其应用于某些线性方程组迭代格式。本文的结果是一般性的，推广了文［３，４］中的结论。     

Coherence Measurement of White Light Emission from Femtosecond Laser Propagation in Air

Strong white light emission is observed from femtosecond laser propagation in air. The divergence angle of the white light emission is measured to be about 5mrad. Young＇s double-slits and a Michelson interferometer are used to investigate the coherence. The wavelength components of the white light emission are identified to have a good spatial coherence and a coherence time of about 0.5ps.     

生物小分子的电分析化学研究：Ⅳ.维生素K3的电化学性质和光谱电化…

研究了维生素Ｋ３在热解石墨电极上的电化学行为，分子定向和分子间的相互作用，用紫外吸收光谱电化学验证了它的电化学还原机理。实验结果表明维生素Ｋ３在热解石墨电极上的反应是受吸附作用控制的３ｅ，２Ｈ＾＋准可逆过程，维生素Ｋ３分子是Ｃ（６，７）位上的Ｈ按垂直向方吸附于热解石墨电极表面的，且吸附分子间存在着相斥的相互作用，其吸附平衡常数约为１．１１×１０＾５，吸附能约为２８．８ＫＪ．ｍｏｌ＾－＾１。吸收光谱