合成气制低碳烯烃K－Fe－MnO／MgO催化剂的研究Ⅰ．MnO助剂的作用

采用ＣＯ加氢反应、ＣＯ－ＴＰＤ、ＣＯ／Ｈ＿２－ＴＰＳＲ及Ｃ＿２Ｈ＿４／Ｈ＿２－ＴＰＳＲ等手段，研究合成气制低碳烯烃反应Ｋ－Ｆｅ－ＭｎＯ／ＭｇＯ催化剂中ＭｎＯ的助剂作用。结果表明ＭｎＯ能大幅度提高低碳烯烃的选择性，尤其是乙烯的选择性；ＭｎＯ能抑制催化剂表面的乙烯加氢，因而有利于提高低碳烯烃的选择性及烯／烷的比值。     

α－Fe_2O_3／SnO_2气敏薄膜的结构与性质

α－Ｆｅ＿２Ｏ＿３／ＳｎＯ＿２气敏薄膜的结构与性质娄向东，杨秀清，李靖华，沈荷生，沈瑜生（河南师范大学化学系新乡４５３００２）（中国科学技术大学材料科学与工程系合肥）关键词α－Ｆｅ＿２Ｏ＿３，ＳｎＯ＿２，双层膜，气敏性能α－Ｆｅ＿２Ｏ＿３具有刚玉结构...     

三环己基锡O，O＇－二（4－氯苯基）二硫代磷酸酯和二丁基锡双［O，O＇－二（4－甲基苯基）二硫代磷酸酯］的分子和晶体结构

三环己基锡Ｏ，Ｏ＇－二（４－氯苯基）二硫代磷酸酯（Ⅰ），Ｃ＿（３０）Ｈ＿（４１）Ｃｌ＿２Ｏ＿２ＰＳ＿２Ｓｎ，Ｍ＿ｒ＝７１８．３６，单斜晶系，Ｐ２＿１／ｎ，ａ＝１６．１５１（２），ｂ＝９．４１５（１），ｃ＝２２．９８７（３），β＝１０５．６９（１）°，Ｚ＝４，Ｄｃ＝１．４１８ｇ·ｃｍ￣（－３），Ｒ＝０．０６３；二丁基锡双［Ｏ，Ｏ＇－二（４－甲基苯基）二硫代磷酸酯］（Ⅱ），Ｃ＿（３６）Ｈ＿（４６）Ｏ＿４Ｐ＿２Ｓ＿４Ｓｎ，Ｍ＿ｒ＝８５１．６６，单斜晶系，Ｐ２＿１／ｃ，ａ＝１２．２８４（４），ｂ＝９．８０７（１），ｃ＝３４．４７１（８），β＝９９．０２（２）°，Ｚ＝４，Ｄ＿ｃ＝１．３７９ｇ·ｃｍ（－３），Ｒ＝０．０４２。化合物Ⅰ具有单分子的四配位变形四面体结构。其Ｓｎ－Ｓ（１）键长为２．５０１（２）；而Ｓｎ与Ｓ（２）的原子间距则为３．５９７；化合物Ⅱ具有单分子的六配位变形八面体结构，其Ｓｎ－Ｓ（１），Ｓｎ－Ｓ（２），Ｓｎ－Ｓ（３）和Ｓｎ－Ｓ（４）的键长分别为２．４９５（３），２．４９３（２），３．２４４（４）和３．２２８（３）。     

毕兹多克隆抗体的制备和分析应用

用琥珀酸酐－碳二亚胺法和氯磺化法合成了毕兹（Ｂｚ）的两种人工抗原Ｂｚ＿ＨＳ＿ｐｒｏｔｅｉｎ和Ｂｚ＿ＳＯ２＿ｐｒｏｔｅｉｎ。由Ｂｚ＿ＳＯ２＿ＢＳＡ（牛血清白蛋白）诱导出的抗血清能够用来测定１０－９ｍｏｌ·Ｌ－１的Ｂｚ，工作曲线的线性范围在３×１０－５～３×１０－９ｍｏｌ·Ｌ－１，相对标准偏差为１３６％（ｎ＝６），回收率在９０％～１１５％。     

超高比表面炭载钼煤气甲烷化催化剂

以沥青中间相为原料，氢氧化钾直接活化，获得了比表面达２３６３ｍ￣２／ｇ的超高比表面炭分子筛（ＣＭＳ）。分别以ＣＭＳ、ＳｉＯ＿２、活性炭和θ－Ａｌ＿２Ｏ＿３为担体，制备了负载钼催化剂，并研究其加压甲烷化反应性能，发现活性依下面顺序增加：θ－Ａｌ＿２Ｏ＿３＜ＳｉＯ＿２＜活性炭（ＡＣ）＜ＣＭＳ。还分别以钼酸铵和磷钼酸（ＨＰＭｏ）为前驱体，制备了ＣＭＳ负载钼催化剂，并考察了其煤气甲烷化活性，发现不同的催化剂前驱体对催化剂反应活性影响很大。根据产物中ＣＨ＿４／ＣＯ＿２的变化，推测ＣＯ在钼催化剂上的甲烷化反应包括如下两个步骤：（１）３Ｈ＿２＋ＣＯ→ＣＨ＿４＋Ｈ＿２Ｏ，（２）ＣＯ＋Ｈ＿２Ｏ→ＣＯ＿２＋Ｈ＿２。     

二氯二苯基锡与单核苷酸配位作用的研究

研究了二氯二苯基锡（Ｐｈ＿２ＳｎＣｌ＿２）与核酸的基本组成单元──单核苷酸在水相中的配位作用，并用热分析、傅利叶变换红外光谱和￣１Ｈ、￣（３１）Ｐ超导核磁共振谱对新配合物Ｐｈ＿２Ｓｎ（５＇－ＡＭＰ）·Ｈ＿２Ｏ、Ｐｈ＿２Ｓｎ（５＇－ＣＭＰ）·Ｈ＿２Ｏ和Ｐｈ＿２Ｓｎ（５＇－ＧＭＰ）进行了详细的表征。结果表明，在配合物中锡仅与单核苷酸的磷酸根结合，给出了配合物的可能结构。     

SnF2的性质及其制备

ＳｎＦ＿２的性质及其制备陈荣，周杰，沈玉华（北京大学化学系１００８７１）（安庆师范学院）ＳｎＦ＿２是介于离子型和分子型之间的化合物，有α、β和γ三种变体，室温下是α－ＳｎＦ＿２，属单斜晶系，单位晶胞中含有４个环状四聚物Ｓｎ＿４Ｏ＿８，这种结构中有两种...     

ZnSnO3陶瓷材料气敏特性与导电机理

Ｘ－射线光电子光谱（ＸＰＳ）分析表明，在２５～３００℃时，ＺｎＳｎＯ３的表面存在及Ｏ￣－两种吸附氧，且随工作温度的增加，逐渐转变成Ｏ￣－或Ｏ￣（２－）。ＺｎＳｎＯ＿３周表面电阻控制型气敏材料，氧的吸附活化能为０．５２ｅＶ。ＺｎｓｎＯ＿３基元件对各种还原性气体都有一定气敏效应，它对乙醇比汽油的分辨率高５倍以上。     

Studies on the Reactivities of Undecatungstogallates K＿n［GaW＿（11）O＿（39）M（H＿2O）］·xH＿2O（M＝Mn，Co，Ni，Cu，Cr，FeorZn）

ＳｔｕｄｉｅｓｏｎｔｈｅＲｅａｃｔｉｖｉｔｉｅｓｏｆＵｎｄｅｃａｔｕｎｇｓｔｏｇａｌｌａｔｅｓＫ＿ｎ［ＧａＷ＿（１１）Ｏ＿（３９）Ｍ（Ｈ＿２Ｏ）］·ｘＨ＿２Ｏ（Ｍ＝Ｍｎ，Ｃｏ，Ｎｉ，Ｃｕ，Ｃｒ，ＦｅｏｒＺｎ）ＬＩＵＪｉｎｇ－ｆｕ，ＺＨＡＮＸｉａｏ－ｐ...     

SnO2超微粒LB膜初探

用胶体化学法制备了ＳｎＯ＿２超微粒（ｕｌｔｒａｆｉｎｅｐａｒｔｉｃｌｅ，ＵＦＰ）水溶胶和有机溶胶，研究了ＳｎＯ＿２ＵＦＰ在十二烷基苯磺酸钠和硬脂酸作用下的ＬＢ膜成膜性，并对ＳｎＯ＿２和ｓｎＯ＿２ＵＦＰ的气敏特性做了初步的探讨．     

Korngrößenänderung beim Carburieren von Wolfram und Sintern von Wolframcarbid

The change of grain size during each stage of the process was studied, mainly by optical and electron microscopy. The grain size has a marked effect on the properties of cemented carbide. In order to determine the process of formation of WC powder, the cross section and the surface of the carburized powder were examined microscopically. The mechanisms of carburization and grain growth were clarified. The microstructural relationship between the WC powder and the cemented carbide was also determined. The Co from the ball milled WC-Co mixed powder was extracted and the remaining WC powder was studied microscopically and by determining the grain size distribution. Methods of particle crushing and their effect on differences between various forms of WC powder were studied. Grain growth in sintering and the effect of grain size distribution were also studied. It was concluded that grain growth begins long before the appearance of the liquid phase. Finally it was pointed out that the inner structure of WC should be studied at the atomic level.     

Effects of ball-to-powder diameter ratio and powder particle shape on EDEM simulation in a planetary ball mill

The effects of the ball-to-powder diameter ratio (BPDR) and the shape of the powder particles on EDEM simulation results and time in the planetary ball mill was investigated. BPDR was varied from 1 to 40/3 by changing the powder particle diameter from 8 to 0.6 ?mm. The size and shape of the powder particles do not give a significant change in both the ball motion pattern and simulation results when BPDR is over 20/3. It can be assumed that the kinetic energy of the ball has nothing to do with the size and shape of the powder particle. The simulation time and data size increase exponentially as BPDR increases. The effect of change of the powder particle shape on the calculated data size is not significant, but the more complicated its shape, the longer the simulation time, which is linearly related to the number of spheres composing a particle.     

快淬NdFeB磁粉颗粒度对聚合物粘结NdFeB磁体永磁性能的影响

研究了快淬ＮｄＦｅＢ永磁粉颗粒及其分布对聚合物粘结ＮｄＦｅＢ永磁材料性能的影响。快淬Ｎｄ－ＦｅＢ永磁粉颗凿大小及其分布显著地影响聚合物结ＮｄＦｅＢ永磁材料的磁性能。适当尺寸的快淬ＮｄＦｅＢ磁粉组合可获得高的结ＮｄＦｅＢ永磁帝主要是由于快淬ＮｄＦｅＢ磁粉硬度高,呈鳞片状,其尺雨越大越难获得高密度,但尺寸太小又将破坏磁粉的结构,导致磁性能恶化。     

Effect of Processing and Aging on Particle Size of Explosives

Influence of such processes as molding powder production, pel-lets pressing and aging under different condit/ons on particle size of TATB ( 1,3,S-trlamino-2,4,6-trinltrobenzene ) and HMX (cyclotetramethylenetetranitramine) was experimentally studied. The results showed that parflele size of these explosives was greatly changed before and airier moldinu powder produc-tion, but for different size grade of explosive this change was not the same; pressing process had also great effect on explosive particle size, but before and after ageing process explosive par-tide size did not change seriously.     

活性ZnO的制备及其表征

用传统沉淀法以超声波振荡方式制备出粒径约为32．Onm的六方晶型ZnO超细粉。其结构经IR和X-射线衍射表征,并测定了其粒径、比表面积和电学性质。     

稀土配合物前驱体热分解法合成Y2O3:Eu3+纳米材料

Y2O3:Eu是一种重要的红色发光材料。国内外生产多采用高温固相法和液相合成法,产物粒径较大,在涂屏(管)前需球磨以减小粒径,这样会造成晶粒劣化而引起光衰以及易引入杂质,使发光材料的发光性能和稳定性下降。因此,围绕荧光粉的粒度及分布、分散性和结晶性的控制     

选择性激光烧结高分子粉末的制备方法

综述了用于选择性激光烧结(SLS)的高分子粉末的制备方法。首先介绍了选择性激光烧结工艺对粉末在粒径、形貌、粒径分布、流动性等方面的性能要求,然后综述了常用的高分子粉末的制备方法包括机械粉碎法、直接聚合法、溶液法,以及一些较为新颖的粉末制备方法,如相分离法、微流体技术、"溶胀"粉碎法、水分散法,并对不同种类的高分子粉末的应用作了介绍。     

Preparation of Ultrafine Cobalt Powder by Chemical Reduction in Aqueous Solution

IntroductionThe preparation of ultrafine metal powders has been extensively studied in past years due to their scientific interests and potential applications1. Ultrafine particles exhibit novel material properties that differ from those of the bulk solid state because of the size effect2-4. In particular, ultrafine cobalt powders have many important industrial applications. They are commonly used in alkaline rechargeable batteries, magnetic recording media, heterogeneous catalysis, and especi…     

Physical characteristics and properties of waterborne polyurethane materials reinforced with silk fibroin powder

Degummed silk filament was pulverized with a home‐made machine to obtain silk fibroin (SF) powder, and the structure, morphology, and particle size of the SF powder were investigated. The individual spherical particles and aggregates with different morphology of silk fibroin coexisted in water. A waterborne polyurethane (WPU) aqueous dispersion was blended with the SF powder to prepare novel blended materials with improved physical properties. The average particle size and zeta potential of the WPU/SF aqueous dispersions were characterized. The result showed that the WPU/SF dispersion with higher SF content exhibited a less negative zeta potential and a larger average particle size. Furthermore, the effect of SF content on the morphology, miscibility, and mechanical properties of the resulting blended films was studied by scanning electron microscopy, wide‐angle X‐ray diffraction, dynamic mechanical thermal analysis, and tensile testing. The films showed an improved Young's modulus and tensile strength from 0.3 to 33.8 MPa, and 0.6 to 5.2 MPa, respectively, with the increasing of SF up to a content of 26 wt %. The negative charges in the periphery and the small particle size made a good effort on dispersing SF powder into the WPU matrix as small aggregates, and the SF powder led to the efficient strengthening of WPU materials. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 940–950, 2010     

Preparation of nanosized nickel powder by direct-current electrolysis combined with high-voltage spark discharge

The possibility of obtaining nanosized nickel powder by simultaneous dc electrolysis and high-voltage spark discharge has been explored. The powder has been prepared from a nickel sulfate-containing electrolyte using soluble nickel anodes at a cathodic current density in the range of 11000–19000 A/m², a voltage on the spark gap of 12–16 kV, and a pulse repetition frequency of 0.5 Hz. The effect of various factors on the synthesis of the powder has been studied and the optimum conditions for its preparation have been found using mathematical experiment design. The size distribution of particles has been determined with a particle size analyzer. The BET specific surface area of the powder has been measured to be 11.7 ± 2.1 m²/g.