七氟丙烷气体清洁灭火剂的灭火原理

基于哈龙（Halon）灭火剂的消防产品是一种最为有效的气体消防系统。根据《蒙特利尔议定书》的建议，一些新的清洁消防灭火剂将用来取代哈龙减火剂。其中一种候选者就是七氟丙烷（Heptafluoropropane）灭火剂以及基于七氟丙烷的全覆盖灭火系统正开始应用于电脑机房、电信交换投施等领域。然而，大泉仍未封七氟丙烷灭火剂的灭火原理有一个全面了解。该类型系统的操作是有其缺点的，比如，使用遇程会产生氟化氩（hydrogen fluorideo本文将回顾哈龙灭火剂的灭火原理及使用中的一些相关问题，然後讨论七氟丙烷的化学分解遇程、灭火原理以及在使用遇程中减少氟化氢产生的添加剂妁工作原理。本文亦将简要介绍将水雾冷却系统（waterspray coolingsystem，WSCS）与七氟丙烷灭火剂结合以减少氟化氢产生的设想，同时会论及如何定义更好的添加剂的标准。     

磷氮溴协效阻燃剂的合成及应用研究

以三氯氧磷、季戊四醇、苯胺和液溴为原料,合成了一种具有成炭结构的磷氮溴协效阻燃剂季戊四醇双磷酸三溴苯胺盐。研究了物料配比、反应时间、反应温度对合成的影响,得出了最佳合成条件。通过IR对产物结构进行了表征。阻燃实验表明：季戊四醇双磷酸三溴苯胺盐对环氧树脂具有良好的阻燃效果,当其用量为20％,Sb2O3用量为10％时,环氧树脂的氧指数可达32．5％。     

Fe（Ⅲ）—5—Br—PADAP—Triton x—100—EGTA析相光度法测定痕量铁

研究了Fe(Ⅲ)-5-Br-PADAP-Triton x-100析相显色体系,建立了测定痕量铁的析相光度法。实验表明,在pH=9.0硼酸-氢氧化钠介质中,Fe(Ⅲ)-5-Br-PADAP-Triton x-100在95℃加热1h形成的配合物被Triton x-100相完全富集,配合物最大吸收波长为556nm,表观摩尔吸光系数为7.10×10~4L·mol~(-1)·cm~(-1),铁含量在0～3.6×1.5~(-5)mol·L~(-1)范围内符合比尔定律,以EGTA、乙二胺、亚氨基二乙酸为联合掩蔽剂,测定人发、面粉中的痕量铁,获得满意结果。     

A technique for simultaneous in situ MAS NMR and on-line gas chromatographic studies of hydrocarbon conversions on solid catalysts under flow conditions

A new technique is introduced allowing simultaneous in situ MAS NMR investigations of hydrocarbon conversions on solids under flow conditions and on-line gas chromatography. For adsorption of methanol on zeolite HBeta, equal amounts of adsorbed molecules were determined by both analytical methods. Studying the synthesis of methyl tertiary-butyl ether (MTBE) on zeolite HBeta using an MAS NMR rotor reactor, a constant yield of MTBE of Y_mtbe= 27% was obtained up to a weight hourly space velocity of 1.4 h^-1. The variation of the reaction temperature led to a simultaneous change of the ¹³C MAS NMR signals of isobutoxy species and of the yield of MTBE determined by on-line gas chromatography which indicates that isobutoxy species act as chemically active compounds. In this first application, the new in situ technique has demonstrated its advantage for a simultaneous investigation of compounds with a long residence time on the catalyst surface and of compounds rapidly leaving the catalyst surface. This revised version was published online in July 2006 with corrections to the Cover Date.     

Basic Mandarin color terms

In comparative studies of basic color terms of various ethnic groups, Berlin and Kay found that the number of basic color terms used is greater, the more highly developed a culture becomes and vice-versa (Berlin and Kay 1969: 16). According to their thesis, peoples possessing the most highly developed cultures use 11 basic color terms, or the equivalents of white, black, red, yellow, green, blue, brown, orange, purple, pink, and gray. These 11 color terms are found in Japanese, Korean, and Cantonese. However, as only six are found in Mandarin, Mandarin was assigned to a lower stage of cultural development. This is incorrect. In an effort to prove this assertion, this author has conducted numerous studies. Based on research of Mandarin color terms and mapping response, this study attempts to prove that Mandarin has long contained the 11 basic color terms noted by Berlin and Kay. However, after conducting a mapping response study, it was discovered that the Berlin-Kay color set (i.e., the Berlin-Kay-MacLaury Munsell set) is inadequate for examining low saturation basic color terms such as he (Br) and cang (grayish BG), the representative colors of which are difficult to fully ascertain. During this study, this author discovered a certain degree of difficulty hindering mutual understanding between Eastern and Western cultures. Consequently, this study seeks to promote a degree of such understanding. © 1997 John Wiley & Sons, Inc. Col Res Appl, 22, 4–10, 1997.     

Influence of gadolinium on microstructure and magnetic properties of sintered NdGdFeB magnets

The effect of Gd content on microstructure and magnetic properties of sintered Nd33.03-xGdxFe65.65B1.32 (x=0-2) was studied in this paper to improve the thermal stability of NdFeB and to reduce the raw material cost. The results showed that better magnet performance could be obtained by adding Gd (0-1.5 wt.%) with partial substitution of Nd in Nd33.03-xGdxFe65.65B1.32. It was also found that the Nd33.03-xGdxFe65.65B1.32 magnets showed the best performance when Gd addition increased to 1.0 wt.%. The temperature coefficient Br (α) could be improved from -0.15%/oC to -0.063%/oC (maximum work temperature 120 oC) and the Curie temperature could be improved from 315 oC to 323 oC because the Gd2Fe14B had positive temperature coefficient Br (α) and higher Curie temperature than that of Nd2Fe14B. The coercivity could be improved from 10.2 to 11.48 kOe and the microstructure was close to ideal microstructure. The magnetic performance decreased sharply by adding Gd (above 2 wt.%) with partial substitution of Nd in Nd33.03-xGdxFe65.65B1.32 because the Gd element concen-trated in the grain boundaries.     

离子液体中间体1-丁基-3-甲基咪唑溴盐的合成

以N-甲基咪唑和1-溴代正丁烷为原料合成1-丁基-3-甲基咪唑溴盐[Bmim]Br,研究了反应时间、反应温度、N-甲基咪唑与1一溴代正丁烷的摩尔比及溶剂对[Bmim]Br收率的影响,产物结构通过。HNMR及FT—IR表征。实验结果表明,在反应温度60℃、反应时间24h、N-甲基咪唑与1-溴代正丁烷的摩尔比1：1．2时,收率为91．93％。     

Brφnsted酸性离子液体中苯甲酸酯、苄酯的无溶剂微波合成

该文以1-甲基咪唑、吡啶、苄基氯、硫酸、磷酸为原料,合成了4种B r nsted酸性离子液体:1-甲基-3-苄基咪唑硫酸氢根盐(a),1-甲基-3-苄基咪唑磷酸二氢根盐(b),N-苄基吡啶硫酸氢根盐(c),N-苄基吡啶磷酸二氢根盐(d),以它们作为催化剂和反应介质,考察了苯甲酸与系列脂肪醇、苄醇与系列脂肪酸、苯甲酸在无溶剂和微波辐射反应条件下的F ischer酯化反应,结果表明,当苯甲酸或苄醇与离子液体的摩尔比为1∶0.5时,无需外加催化剂,反应即可在化学计量条件下进行,12~20 m in完成反应,苯甲酸酯与苄酯的收率分别为77%~98%和78%~98.5%,气相色谱纯度≥95%。离子液体循环使用3次,催化活性仅下降1.8%~3.4%。     

I2/Bronsted酸性离子液体介导的ε-环己内酯的合成研究

以I₂/Bronsted酸性功能化离子液体1-羧甲基-3-甲基咪唑硫酸氢根盐(［MCMIM］HSO₄)作为反应体系,H₂O₂（35%）为氧化剂,考察环己酮的Baeyer-Villiger氧化反应,结果表明,n（环己酮）∶n（H₂O₂）∶n（离子液体）=1∶3.5∶（0.2～0.6）时,只需加入微量I₂,反应即可在室温下顺利进行,反应时间2 h,ε-环己内酯收率72.7%～78.2%。离子液体经萃取、减压蒸馏除水和真空干燥即可循环使用,循环使用3次,产物酯收率略有下降。     

［EMIM］Br-AlCl3离子液体的合成

采用N-甲基咪唑、溴乙烷、AlCl₃常规回流法以及微波法合成离子液体,研究［EMIM］Br中间体的产率;采用量子化学方法计算离子液体结构,明确合成反应的机理;通过紫外光谱和红外光谱表征［EMIM］Br-AlCl₃离子液体的结构;测试离子液体的密度、电导率等性质。结果表明：常规回流法以N-甲基咪唑和溴乙烷为原料,在70℃温度下反应5 h,反应产率为87.9%;微波法反应时间1000 s,产率为94.2%;40℃下密度为1.46 g·cm^-3,电导率为21 S·m^-1;用DFT B3LYP 量子化学计算方法研究离子液体的构型,离子液体的合成反应遵循SN2反应机理;紫外光谱和红外光谱表征了［EMIM］Br和AlCl₃/［EMIM］Br离子液体的结构。