Crystal Structure of Ethyl 4-benzoyl-1a,2,3,4-tetrahydro-3-methyl-1a-(4-methylphenyl)-1H-azirino〔1,2-a〕〔1,5〕 benzodiazepine-1-carboxylate(C_(28)H_(28)N_2O_3)

１ＩＮＴＲＯＤＵＣＴＩＯＮＢｅｎｚｏｄｉａｚｅｐｉｎｅｃｏｍｐｏｕｎｄｓａｒｅｉｍｐｏｒｔａｎｔｐｈａｒｍａｃｅｕｔｉｃａｌａｇｅｎｔｓ〔１,２〕．Ｒｅｃｅｎｔｌｙｉｔｈａｓｂｅｅｎｆｏｕｎｄｔｈａｔｂｅｎｚｏｄｉａｚｅｐｉｎｅｔｒｉｃｙｃｌｉｃｄｅ...     

Synthesis and Crystal Structure of a Mixed Cu - Cd Bim etallic Com plex ｛〔 Cu Cd(pba)( H_2 O)_3〕·2 H_2 O｝ _n

１　ＩＮＴＲＯＤＵＣＴＩＯＮＨｅｔｅｒｏｍｅｔａｌｐｏｌｙｎｕｃｌｅａｒｃｏｍｐｌｅｘｅｓｈａｖｅｂｅｅｎｔｈｅｓｕｂｊｅｃｔｏｆｍａｎｙｒｅｃｅｎｔｓｔｕｄｉｅｓｔｏｅｌｕｃｉｄａｔｅｔｈｅｍｅｃｈａｎｉｓｍｏｆｓｐｉｎｃｏｕｐｌｉｎｇｂｅｔｗｅｅｎｔｈｅｍｅｔａｌｉｏｎｓ〔１,２〕,ｍｉｍｉｃｋｉｎｇｔｈｅａｃｔｉｖｅｓｉｔｅｏｆｓｏｍｅｍｅｔａｌｅｎｚｙｍｅｓｃｏｎｔａｉｎｉｎｇｄｉｓｓｉｍｉｌａｒｍｅｔａｌｉｏｎｓ,ｓｕｃｈａｓｃｙｔｏｃｈｒｏｍｅｏｘｉｄａｓｅａｎｄｓｕｐｅｒｏｘｉ…     

苯酚在热氧化法制备的SnO2/Ti 电极上的电氧化研究

A SnO₂/Ti electrode prepared by thermal oxidation was used as the anode for galvanostatic electrolysis in acidic solution containing phenol, the time-dependances of phenol concentration,chemical oxygen demand in solution(COD)and instantaneous current efficiency were determined during electrolysis.The results show that with the SnO₂/Ti anode instead of Pt,the COD significantly decreases at the same charge passage, and average current efficiency of oxidation increases by three times The mechanism for phenol oxidation at two electrodes was discussed.     

单分子结的构筑及分子电导性质的测试

分子电子学已成为21世纪研究的热点. 通过将具有特定功能的分子连接在纳米尺度金属电极之间从而构筑包括分子导线、开关、整流器在内的各种分子尺度电子器件, 这引起了科学家们广泛的研究兴趣. 在分子电子学研究中, 构筑金属/分子/金属(MMM)分子结是研究分子器件中电子传输性质的关键. 尽管已经取得了很大的进展, 目前在纳米尺度下构筑稳定可靠的MMM分子结并测试单个分子的电学性质仍然面临很多挑战. 本文着重对单分子电学性质的测试技术和相关理论研究的最新进展以及存在的挑战做了概述.     

Rapid Thermal Annealing Effects on Structural and Optical Properties of Self-Assembled InAs／GaAs Quantum Dots Capped by InAIAs／InGaAs Layers

Effects of rapid thermal annealing on the optical and structural properties of self-assembled InAs/GaAs quantum dots capped by the InAlAs/InGaAs combination layers are studied by photoluminescence and transmission electron microscopy. The photoluminescence measurement shows that the photoluminescence peak of the sample after 850℃ rapid thermal annealing is blue shifted with 370meV and the excitation peak intensity increases by a factor of about 2.7 after the rapid thermal annealing, which indicates that the InAs quantum dots have experienced an abnormal transformation during the annealing. The transmission electron microscopy shows that the quantum dots disappear and a new InAlGaAs single quantum well structure forms after the rapid thermal annealing treatment. The transformation mechanism is discussed. These abnormal optical properties are attributed to the structural transformation of these quantum dots into a single quantum well.     

SYNTHESES OF POLYMER-BOUND RHODIUM COMPLEXES AND THEIR APPLICATION AS CATALYSTS FOR THE HYDROFORMYLATION OF DIISOBUTYLENE (Ⅰ)

Copolymer of styrene-divinylbenzene in bead form (with DVB 8%, average pore radius 3.0×10~2, specific surface area 25m~2/g, particle size 0.2—0.4mm) was made by the suspension polymerization. After chloromethylation, the beads were then reacted with lithium diphenyl phosphine and various amines separately. Two types of polymeric ligands, i.e. polyvinylbenzyl diphenyl phosphine and eight kinds of polyvinylbenzyl amines were thus obtained. In order to prepare the polymer-bound rhodium complexes, the ligands were then reacted with [Rh(CO)_2CI]_2. The initial composition and structure of the polymeric complexes were verified by IR spectra. The complexes synthesized above were used to catalyze the hydroformylation of diisobutylene under conditions of 110℃, 100(120) kg/cm~2 and H_2/CO=1:1. The effects of the donor atoms (N, P) on the activity of the two types of catalysts and the N-substituted groups on the activity 'of polymeric amine-rhodium complexes were examined.     

奥本海默的成功和衰落

一、原子弹之父 1945年7月 16日晚上,正在波茨坦参加美、英、苏三国首脑会议的美国新任总统杜鲁门接到来自五角大楼的密电.电文说:“今晨手术已做,结果令人满意,出乎所料,格罗夫斯大夫甚感欣慰。”[1]杜鲁门接到这个密电后,踌躇满志,显露出一副不可一世的神情.参加会议的英国首相邱吉尔事后回忆:杜鲁门(返回会议后)看上去判若两人,他以一种尖刻的、说一不二的架势同俄国人进行争论.电文中的“手术”,是指当天清晨第一个原子弹试爆成功,格罗夫斯大夫是这项工程的军方负责人格罗夫斯将军.其后,美国试验核武器的计划——曼哈顿工程的内幕逐渐披…     

CMC-Na/TETA-B62型蛇笼树脂对Ag+、Cr3+和Hg2+的吸附性能

研究了自合成的蛇笼型螯合树脂三乙烯四胺交联甘油环氧树脂／羧甲基纤维素体系对Ag^ 、Cr^3 、Hg^2＋的吸附量，吸附动力学，等温吸附过程等静态吸附性能，同时研究了PH值等因素对吸附性能的影响。实验结果表明，该树脂对Ag^ 、Cr^3 具有较强的吸附选择性，在Ag^ 、Cr^3 、Hg^2＋3种离子共存时能选择吸附Ag^ ，其选择性系数分别为KAg/Hg^2 ＝10．31、KAg^ /Cr^3 =1.77,KCr^3 /Hg^2 =5.83。该树脂对上述3种离子的吸附量分别达2.99mmol/g、1．69mmol/g、0．29mmol/g，该类树树可用于含重金属离子污水的处理和金属离子的分离等方面。     

A Quasi-Interpolation Satisfying Quadratic Polynomial Reproduction with Radial Basis Functions

In this paper,a new quasi-interpolation with radial basis functions which satis- fies quadratic polynomial reproduction is constructed on the infinite set of equally spaced data.A new basis function is constructed by making convolution integral with a constructed spline and a given radial basis function.In particular,for twicely differ- entiable function the proposed method provides better approximation and also takes care of derivatives approximation.