Ring-opening Polymerization of Chloromethyl Thiirane with Catalytic Systems Composed of Lanthanide Compound and Ethyl Aluminum Sesquichloride

Thering-openingpolymerinahonofchloromethylthiirane(CMT)wasfirstcatriedoutinl952.lLater,itwasfoundthatcahoniccatalystSH,SO','CF3SO3H,andBF,.OEt2'couldpolymerizeCMTbutwithoutdefndtedataofmolecularweightandcatalghcefficiency.Anioincinihators,suchasKOHandNaNH2,areineffechve.2OrganocomPoundsbasedoncadminIn,zinc,andaluIninmcanconvertCMTtoviscousoil.2TwocomPonentZiegler-NattampecatalystsbasedonneodyIninmtris(2-ethylhexylphosphonate),Nd(Pzoo)s,andtriisobutylaluIninUmeAlitedhighactivity…     

钠蒸汽中通过四波参量过程产生紫外相干辐射的光谱特性

本文报告在钠蒸汽中,通过四波参量过程在327nm,328nm,330nm及333nm处得到紫外相干辐射及对它们光谱特性的研究结果。其中333nm信号的可调谐范围较宽,是一可能应用的紫外相干光源。 关键词：     

The Molecular and Crystal Structure of an Inclusion Compound Formed between Acetylferrocene Pyridine-2, 6-diformylhydrazone and Ethanol

1INTR0DUCTI0NIthasbeenreportedthatacety1ferrocenepyridine-2,6-diformylhydrazonewasabletoformbinuclearcomplexeswithrareearthpicratesintheketoforminourpre-viouswork[li.Inthecourseofpurificati0n0fthisligand,wefoundthatitselective1yformsstableinclusi0ncrystalswithethanol.Inordertoelucidatethecoordinationbe-havi0urandtheinclusionpatternofthisligand,themolecularandcrystalstructureofitsinclusioncompoundwithethanolwasreportedinthepresentpaper-2EXPERIMENTAL2.1GeneraIConsiderationTheC,HandNmi…     

激光等离子体中平台型密度分布结构的边界条件和连接条件

本文仔细地分析了以前在自洽密度分布边界条件和连接条件处理中存在的缺点。为了确切地反映真实的边界,用自相似解把真空边界和等离子体静止上流分别与下密度平台和上密度平台连接起来,在声速点实现了完好的匹配。我们的分析结果与计算机模拟完全一致。 关键词：     

Semi-gas kinetics model for performance modeling of flowing chemical oxygen-iodine lasers (COIL)

The gas pressure in a laser cavity of flowing chemical oxygen-iodine laser (COIL)is about 133.31333 Pa[1]. In this pressure range, effects of homogeneous and inhomo-geneous broadening competing with each other on the performances of a COIL are no-ticeable. Generally, a rate equation (RE) model is adopted to the performance modeling of a supersonic COIL, such as in refs. [1—4]. This model assumes the spectral line pro-file is homogeneously broadened. Homogeneous broadening assumption sim…     

IP安全体系结构

介绍了IPSec的体系结构及其提供的安全服务．重点讨论了IPv6中用以实现IPSec安全服务功能的认证报头AH、封装净荷ESP报头及IPSec默认的密码算法。分析了IPSec的安全性优点与存在的问题，并提出了改进建议。     

室温下聚四氟乙烯的压致相变

用激光拉曼光谱研究了PTFE在室温下的压致相变,压致Ⅳ-Ⅱ和Ⅱ-Ⅲ相变时,相应的拉曼光谱都有明显的变化,讨论了压致相变时的构象变化.用Tait方程和Murnaghan方程处理等温压缩数据,也发现了Ⅱ-Ⅲ压致相变.首次计算了高压相的模Gruneisen参数.     

Photocoupling Reactions of Haloaromatic Hydrocarbons With Aromatic Compounds——Synthesis and Mechanism

An effective method of synthesizing polyaromatic hydrocarbons with high selectivity was developed through our research work on the photocoupling reactions between several haloaromatic hydrocarbons and aromatic compounds. The structures of polyaromatic hydrocarbons synthesized were determined by IR, UV, ~1H NMR, MS and elemental analysis, and the crystal structure of 3-(1-naphthyl)-coumarin was established by an crystallographic analysis. Further study of the regioselectivity, orientational effect of substituents, solvent effect, sensitizing and quenching effect supported the proposed mechanism of this type of reaction involving election transfer process under excited triplet state.     

光子加速器的理论研究

研究了光子加速器(即利用等离子体中的朗谬尔波实现光脉冲频率上转换)所涉及的基本物理问题.文中导出了在存在朗谬尔波的条件下,光脉冲频率对于等离子体本底密度及电子密度扰动的依赖关系,并就最大频率转换、光脉冲俘获、波的加速位相(accelerating phase)以及位相滑动(phase slippage)效应进行讨论.     

稳态自洽密度分布的三参量解族

本文利用严格的解析方法求得了激光等离子体中稳态自洽密度分布的三参量解族。讨论几种特殊情况,指出Lee等人给出的平台型密度分布只是其中的一种特殊情况。 关键词：