A facile synthesis of per (poly )fluoroalkyl substituted α-amino acid derivatives

Initiated by CrCl3/Fe redox couple, per(poly)fluoroalkyl iodides added to methyl a-acetylamino acrylate, giving B-per(poly)fluoroalkyl a-amino acid derivatives in good yields.     

铬酸引发丙烯腈与苎麻纤维接枝共聚反应

棉、麻类织物通过与乙烯类单体接枝共聚可以提高染色性、皱折回复性、耐磨性、防污性等［‘j．纤维素接枝共聚物的合成始于50年代，目前研究最多的是乙烯类单体通过自由基活性中间体与纤维素进行接技共聚，但此法存在一个突出的问题是在接技共聚的同时生成大量均聚物．铬酸（下文用Cr’“表示）是公认的强氧化剂，据报道［’－‘j，它单独存在时并不能引发乙烯类单体聚合，如果用Cr‘”引发乙烯类单体与纤维素接技共聚，均聚物的生成量将会减少．本文以Cr’”为引发剂，将丙烯睛（AN）与艺麻纤维进行接技共聚，考查不同条件对接技率及均聚…     

Cr－Ag／γ－Al_2O_3催化剂在CO氧化反应中Ag的助催化作用

Ｃｒ－Ａｇ／γ－Ａｌ_２Ｏ_３催化剂在ＣＯ氧化反应中Ａｇ的助催化作用陈平，朱波，钟依均，罗孟飞，李少华，吴红丽（杭州大学催化研究所杭州３１００２８）（杭州大学中心实验室杭州）关键词氧化铬，氧化银，氧化铝，负载催化剂，还原特性，一氧化碳，氧化活性催化燃烧...     

Reactivity of tetrahydrochromeno[2,3‐b]indoles: chromic indicators of cyanide

The synthesis and reactivity of a tetrahydrochromeno[2,3‐b]indoles are reported. Evidence for reversible ring‐opening is based on H/D exchange and trapping experiments. These compounds readily undergo reaction with tetra‐n‐butylammonium cyanide. The cyanide reaction is 10–100× faster when the solution is irradiated with 350 nm light. Reaction with trimethylsilyl cyanide occurs only with UV irradiation demonstrating photoreactivity. The rate of tetrahydrochromeno[2,3‐b]indole ring‐opening is greater for (i) Me substitution at the hemiaminal carbon (compared to Ph), and (ii) substitution of fluorine at the 9‐position of the indole. Under acidic conditions, the ring‐opened indolium ion is observed. Copyright © 2013 John Wiley & Sons, Ltd.     

酸催化环合合成△~(1,8)-5,5-双甲基-六氢-7-氧代-萘-2-乙酸甲酯

近年来一些2位含氧的萜类化合物引起了人们的兴趣,虽已报道一些2位含氧的三环三烯萜的合成,但化合物2-oxo-(?)nt-manool     

慢性肺心病患者血清Cu,Zn及Cu/Zn比值的分析研究

分析了65例慢性肺心病患者血清Cu,Zn的含量及Cu/Zn比值，并与健康对照组比较。结果显示，慢性肺心病患者组血清Zn的含量与健康对照组比较有高度显著性差异（P＜0．01），Cu的含是有显著性差异（P＜0．05），Cu/Zn比值有显著性差异（P＜0．05）。提示慢性肺心病与微量元素Cu、Zn元素的含量变化有一定的关系，为研究元素医学与治疗慢性肺心病提供了必要的依据。     

A study of chromic oxide decomposition in an RF argon plasma

Vapor-phase thermal decomposition of chromic oxide in an rf argon plasma was studied using a new experimental system. Homogeneous and heterogeneous modes of reaction were compared, the overall process efficiency being substantially higher for the process carried out entirely in the vapor phase. Reaction products were collected along the reactor wall and studied by chemical methods as well as SEM, X-ray, and IR absorption. The collected powder was highly reactive, fine-grained, and of semiamorphous nature, the average particle size being well below 100 nm. Temperature profiles recorded below the coupling coil by spectroscopic methods were typical of an rf plasma, showing maxima slightly exceeding 5000 K, with the presence of off-axis peaks. Local Cr contents and concentration ratio (Cr)/(Cr₂O₃) in the plasma were determined from the deposition data obtained. A diffusion process was assumed for the wall-deposit buildup. The results obtained confirmed the advantages of using plasma vapor-phase systems, these being higher-efficiency processes and more reliable models than those obtained in the case of gas-solid plasma reactors, where solid particles are injected into the plasma. The thermal decomposition conversion of Cr₂O₃ into Cr was about 8 times higher in the homogeneous gas phase than in the plasma solid phase, all other conditions being equal.Nomenclature c velocity of light, cm × s^–1 - C _Cr ^m metallic Cr content, % by wt. - C _Cr ^t total Cr content, % by wt. - D species diffusivity, cm² · s^–1 - E energy of excited level, eV - f oscillator strength - F rate of species deposition, mol · cm^–2 · s^–1 - g statistical weight - h Planck's constant, J · s^–1 - I radial emission intensity for a given spectral line at a given radius in the plasma, W · sr^–1 · cm^–3 - k Boltzmann's constant, J · K^–1 - l length of collected deposit, cm - m mass of collected deposit, g - M molar weight of Cr - M _Ar ^a molar flow of axial argon, mmol · s^–1 - M _Ar ^p molar flow of peripheral argon, mmol · s^–1 - M _{Cr 2}O₃ molar flow of evaporated Cr₂O₃, mmol · s^–1 - Cr(I) concentration, cm^–3 - Q _T partition function at temperatureT - r reaction radius, cm - R radius of quartz tube, cm - t duration of deposition, s - T temperature, K - total extent of Cr₂O₃ decomposition into Cr, % - Z position of a plane normal to the plasma axis downward the lower turn of rf coil, cm Greek Letters molar ratio of Cr and Cr₂O₃ in deposit - wavelength, nm - species concentration, mol · cm^–3     

绿色化学与铬盐工业的新一代产业革命

本文介绍了铬盐生产的绿色化学研究的内容和方法, 所开拓的熔盐液相氧化-高浓介质单向分离-介稳态相分离-碳化循环转化的多相反应与分离系统的绿色化学新原理, 资源深度利用-反应介质内循环-零排放的完整绿色工业化学体系。