多媒体教学手段在天文教育中的应用--天文教学系列软件"探索宇宙"简介

结合中国目前天文学教育的现状和我系开展基础天文学教学的体会,对天文学教学中如何利用多媒体的手段进行了论述,并重点介绍了天文系列多媒体教学软件<探索宇宙>的特点和主要内容.     

Low-temperature reaction of magnesium with fluorobenzene

The low-temperature reaction of magnesium with fluorobenzene has been investigated. Joint condensation of magnesium and fluorobenzene vapours at low temperatures quantitatively gave phenylmagnesium fluoride in one stage.     

The prediction of the peak width at half height in HPLC

The prediction of the peak width at half height is an important aspect in the optimization of the chromatographic operating conditions. In this paper, a linear relationship, between the peak widths at half height and the retention values with various isocratic elution is observed. In gradient elution, however, the relationship between the peak widths at half height and the so-called invented retention values that correspond to the mobile phase composition by eluting the solute from the column end is developed. We believe that there is almost the same band width at half height inside the column (in unit of length) for different solutes. The peak width at half height in the chromatogram (in unit of time) is mainly determined by the capacity factor of the solute when it is eluted from the column end. The larger the capacity factor of a solute eluted from the column end, the more slowly will be the solute eluted from the column end and the wider will be the peak width at half height. It is possible to predict the peak width at half height in various isocratic and gradient elutions by using this linear relationship.     

Fibonacci,Lucas序列与高阶Bernoulli多项式

本文给出了包含Ｆｉｂｏｎａｃｃｉ序列｛Ｆｎ｝、Ｌｕｃａｓ序列｛Ｌｎ｝及高阶Ｂｅｒｎｏｕｌｌｉ多项式Ｂｎ（Ｋ）（ｘ）的一些恒等式。     

Deuterium NMR studies of inositol liquid crystals [1]

Deuterium NMR investigations are presented on members of two new mesogenic series derived from the naturally occurring stereoisomers myo- and scW/o-inositol. Tetraethers of these two series exhibit thermotropic columnar phases in which the columns are apparently formed by stacked hydrogen bonded dimers of these molecules which chemically are vicinal diols. Deuterium NMR measurements were performed on the tetraoctyl homologues 2e (a cis diol) and 3e (a trans diol) of these series. We have investigated mixtures of these diols with small amounts of benzene-d₆ as probe molecules as well as samples of the neat diol compounds deuteriated at their hydroxyl groups. The results obtained show that the mesophases of both compounds are uniaxial and align partially in a magnetic field upon slow cooling from their isotropic liquids. The alignment is with the director parallel to the field direction indicating that the anisotropic magnetic susceptibility of this mesophase is positive. The deuterium quadrupole splitting of the benzene-d₆ probe in both systems is temperature dependent and in the trans diol 3e it even changes sign. This is interpreted in terms of a model in which the benzene-d₆ probe equilibrates rapidly between two (or more) solvation sites with quadrupole splittings of opposite signs The deuterium spectra of the neat deuterium labelled cis diol 2e exhibit two different signals due to the two deuterons which are located at the axial and equatorial hydroxyl groups. This indicates that there is no fast intra- or intermolecular exchange of the hydroxyl hydrogens. The overall quadrupole splittings of the hydroxyl deuterons in this compound are highly reduced compared to their static values and this is interpreted in terms of motional modes involving both reorientation of the hydroxyl deuterons about their C-O axis and overall reorientation of the molecules (or pairs of molecules) around the columnar axes. The corresponding spectra of the neat deuteriated trans diol 3e exhibit a single spectrum indicating that both hydroxyl deuterons in this compound are equivalent, or very nearly so. Within the mesophase region the spectrum undergoes gradual changes due to the increase in the molecular mobility, but the overall motional narrowing is less than in the cis isomer 2e. Apparently due to stronger hydrogen bonding in the trans isomer 3e the precession of the hydroxyl groups is hindered and a fast molecular reorientation is only possible at high temperatures.     

Dynamics of a pair of coupled nonlinear oscillators

A pair of coupled classical oscillators with a general potential and general form of coupling is investigated. For general potentials, the single-frequency solution is shown to be stable for small excitations. For special potentials, such system remains stable for an arbitrary excitation. In both cases, the stability does not depend on the form of coupling. Transition to the instability regime follows from the way how nonlinear potential entrains the energy transfer between the oscillators. Relation between the existence of multi-frequency quasi-periodic or periodic solutions and the instability of single-frequency ones is discussed.     

黄磷废水处理系统中氰降解菌的筛选

首次对含有氰化物的黄磷废水进行了氰降解菌筛选优化,共得耐氰菌20株,其中有9株的降氰率在90％以上,且AB2001003菌株降氰率在97.1％以上.该菌能在72 h内使含CN~-50mg·L~(-1)的黄磷废水降至0.5 mg·L~(-1)以下,达到国家一级排放标准.该菌的最佳生长pH7.7,最佳温29℃.     

￣（45）Ca跨膜流动测定技术用于中药钙拮抗作用的研究

应用￣（４５）Ｃａ跨膜流动测定技术研究钙拮抗剂ｖｅｒａｐａｍｉｌ、中药西红花（ＣｒｏｃｕｓＳａｔｉｖｕｓＬ．）、“地奥心血康”（ＤＡＸＸＫ）、川红花（ＣａｒｔｈａｍｕｓｔｉｎｃｔｏｒｉｕｓＬ．）及银杏叶（ＧｉｎｋｇｏｂｉｌｏｂａＬ．）等对大鼠主动脉￣（４５）Ｃａ跨膜内流的作用，以确定其对细胞膜Ｃａ￣（２＋）通道影响。实验结果表明：西红花、川红花、ＤＡＸＸＫ对平滑肌细胞膜上电压依赖Ｃａ￣（２＋）通道（ＰＤＣ）和受体操纵Ｃａ￣（２＋）通道（ＲＯＣ）都有阻滞作用，并以西红花的阻滞作用最强；而银杏叶对细胞膜Ｃａ￣（２＋）通道无阻滞作用。     

Orthogonally linear polarized lasers(Ⅰ)--principle and devices

Two kinds of orthogonally polarized lasers, i.e. Zeeman dual-frequency lasers and four-frequency ring lasers (laser gyros) have been developed since the invention of lasers, in which circularly polarized lights oscillate. This paper summarizes recent progress of the study on orthogonally linear polarized lasers with the standing wave cavity. Firstly, the expression of producing orthogonally linear polarized lights in standing wave cavity, i.e. laser frequency splitting, is given. Almost all the birefringence effects made in laser cavity are used to produce orthogonally linear polarized lights. The effect includes quartz crystal birefringence effect, calcite birefringence effect,stress (photo-elastic) birefringence effect and electro-optical birefringence effect. Secondly, several physical phenomena of orthogonally linear polarized lasers are discovered such as aberrance of frequency splitting curves caused by optical activity of quartz crystal, order-passing of longitudinal modes with frequency splitting and strong modes competition. Finally, because the traditional Zeeman dual frequency laser cannot output frequency difference larger than 3 MHz, the approaches of obtaining larger frequency difference are studied. The sequential results, several kinds of orthogonally polarized lasers, are described, such as birefringence dual frequency lasers outputting a frequency difference from 40 MHz to hundreds of megahertz, birefringence-Zeeman dual frequency lasers outputting a frequency difference from 1 MHz to hundreds of megahertz, the LD pumped YAG birefringence dual frequency laser outputting frequency difference of several gigahertz, and the lasers whose longitudinal mode spacing is c/4L instead of c/2L.