罗柯夫斯基线圈频率响应特性的测量方法

罗柯夫斯基线圈是测量陡脉冲电流的一种重要装置,其方波响应上升时间能达到纳秒量级,但是,它只能在一定频率范围内作线性测量。为了更好地分析罗柯夫斯基线圈测量灵敏度的频率特性,本文介绍了对西安交通大学研制的该线圈作的频率响应特性测定结果。 文中着重介绍了频响测量的点频法,并叙述了有关影响因素。例如:对信号源、标准电压表、匹配负载等一些专门要求。给出了实测曲线,还介绍了线圈本身各种集中参数的测量结果。     

离子膜富集—XRFA法测定Cr（Ⅲ）和Cr（Ⅵ）

本文利用离子交换膜富集和分离Ｃｒ（Ⅲ）与Ｃｒ（Ⅵ），并用ＸＲＦＡ测定。     

SOLID STATE HIGH RESOLUTION ~(13)C NMR STUDY OF CHINESE MUDSTONE KEROGENS

Using ~(13)C CP MAS TOSS DD NMR, some rules governing the variations of structureparameter and fractional contents for various aliphatic carbon in the mudstone kerogensburied in different depths in China are first reported in this paper, and the preliminarystudies on their natural evolution as well for the formation of oil and gas have been made.The influence of T_(CP), T_(CH), f_(rsc) on quantity measurement of CP in kerogens is discussed.     

二乙胺合三(2-苯骈噻唑基)硼烷在电子电离质谱中的反应

在研究二乙胺合三(2-苯骈噻唑基)硼烷的EI质谱时,发现了在EI条件下三(2-苯骈噻唑基)硼烷的二聚作用,并用高分辨质谱、FAB质谱证实了二聚体的存在。用MIKE谱阐明了二聚体离子主要的裂解途径。提出了二聚体形成的一种机理及其可能的结构。     

^1H NMR Study of Polyvinylalcohol Irradiated by Ultra-violet

The effect of Ultra-violet light on the structure and motion of the polyvinyl alcohol (PVA) chains was studied by IH NMR, spin-lattice relaxation and IR spectroscopy. The results indicated that with the increase of irradiation time, the intensity of the polymer hydroxyl proton peaks decreased and finally vanished, which suggested the self-condensation between the hydroxyl groups proceeded. No methyl proton peaks appeared in the spectra after irradiation shows that there is no cleavage of polymer chain. The longer the irradiation time is, the wider the proton peak of the residual water of the solvent is and it shifted toward low field. This result implies that the hydrogen bonds formed between the polymer and the residual water. The absorption peak of hydroxyl group of the polymer moves toward the lower wave number in the IR spectrum that showed the existence of the hydrogen bonds between the PVA macromolecules.     

断口定量分析中高度参数的扫描电镜测定

在断口定量分析中根据双目成象原理,运用扫描电镜技术,实现对断口上高度参数的测量,将扫描电镜中获得的立体感觉转变为相应的几何参数,从而可以从断口上获得高度参数的定量数据。同时还分别讨论了进行断口高度参数测量的倾转法和剖面法。     

STUDIES ON THE STEREOSELECTIVITY AND SUBSTITUTED GROUPS OF (+)-CAMPHOR DERIVATIVES

From (+)- camphor, six new (+)-camphor derivatives were synthesized. According tothe structure and chemical properties of the derivatives, the relation between the substitutedgroups and the stereoselectivity of alkylations and reduction was examined. It is found thatthe chemical shift of protons of C(8), C(9) methyl groups and chemical properties of carbonylO(2) are associated with the substituted groups.     

四卤化碳: 强碱反应体系顺磁共振研究

单电子转移反应是物理有机化学中十分活跃的研究领域之一,现已发现许多有机反应中都存在着单电子转移过程。探讨不同的单电子转移反应体系,了解其中电子给、受体之间的相互作用,不仅对深入了解反应机理有理论     

实现ICF束匀滑的二元光学器件设计与制作

 采用爬山法和模拟退火法相结合的混合优化算法,设计得到了二元光学器件的良好位相结构;基于高斯分布随机信号模型,分析了二元光学器件对输入波面位相畸变的宽容度。首次针对波长λ＝1.053μm研制了φ10mm的连续位相二元光学器件,并通过多级衰减片及CCD实现了焦斑光强分布测量,结果表明得到了边缘陡峭、旁瓣小、中心主瓣具有一定均匀性、且没有中心零级锐脉冲的焦斑光强分布。     

Studies on monodispersed colloidal particles of doped yttrium compounds

Monodispersed particles of doped yttrium basic carbonates were prepared at aging at elevated temperature corresponding salts solutions in the presence of urea. Coprecipitation in mixed solutions of yttrium, lanthanum and neodymium salts under similar experimental conditions yielded composite particles of basic carbonates. The content of the three metals in the solids followed closely the initial composition of the reacting solutions. On calcination all prepared solids converted to their corresponding oxides while retaining their particle morphology. The so-prepared powders were characterized by various techniques.