环氧乙烷银催化剂中助催化剂的研究进展

介绍了乙烯氧化制环氧乙烷银催化剂中常见的几种助催化剂；碱金属，卤素，碱上金属，稀土金属，铊，钼，钨硫，铼，锰和镍等，并对其中的铯，氯，钡，铼的助催化作用机理也作了简要介绍。     

SO_4~（2－）／ZrO_2超强酸催化剂的结构表征

用ＢＥＴ法分析了制备条件对ＳＯ＿４￣（２－）／ＺｒＯ＿２超强酸催化剂的比表面和孔结构的影响，用ＳＥＭ观察了催化剂的表面形貌。结果表明，引人ＳＯ＿４￣（２－）后催化剂的比表面和比表面的热稳定性都增大了，在Ｈ＿２ＳＯ＿４浓度为１．０ｍｏｌ／１和焙烧温度约７７３Ｋ时催化剂的比表面较大。制备Ｚｒ（ＯＨ）＿４时用浓氨水得到的催化剂的比表面、平均孔径和孔体积都较大。ＳＯ＿４￣（２－）／ＺｒＯ＿２催化剂的孔为平均孔径３－５ｎｍ的中孔。ＳＥＭ结果表明，ＳＯ＿４￣（２－）／ＺｒＯ＿２催化剂的表面为很不平整的蜂窝状。     

NO分解催化剂Cu/分子筛的ESR研究 Ⅰ.水合铜分子筛的ESR研究

系统地比较了在各种不同制备条件下制得的Ｃｕ／ＺＳＭ－５、Ｃｕ／丝光沸石、Ｃｕ／镁碱沸石和Ｃｕ／毛沸石的ＥＳＲ谱，至少六种水合Ｃｕ物种被发现，而且发现分子筛的腔结构对Ｃｕ物种的存在状态有很大的影响。     

Sonochemical Activation of Al/Ni Hydrogenation Catalyst

This paper proposes a sonochemical approach to the nanostructuring of Al/Ni catalyst with high content of accessible Ni centers and a high reusability. The surface and bulk composition as well as pore size distribution of this catalyst are controlled synergistically by adjusting the ultrasound intensity in aqueous solution. Sonochemical activation of Al/Ni alloy leads to formation of mesoporous Al/Ni metallic based frameworks with surface area up to 125 m² g^?1, and regular distribution of nickel active center in the porous matrix. One of the opportunities of porous Al/Ni catalyst is that due to a time‐resolved controllable formation of protective oxide layer it can be stored and handled under air in comparison to traditional Raney catalysts which need inert conditions. The Al/Ni catalyst is characterized by scanning electron microscopy (SEM), electron diffraction spectroscopy (EDS), X‐ray photoelectron spectroscopy (XPS), confocal scanning fluorescence microscopy (CSFM), solid‐state NMR experiments, and powder X‐ray diffraction analysis (PXRD). The catalytic activity was investigated for the hydrogenation of acetophenone.     

A proposed approach for setup time reduction through integrating conventional SMED method with multiple criteria decision-making techniques

Short setup time is an essential element for the effective implementation of many lean pillars, i.e., JIT, and Kanban. Most of the current setup reduction methodologies are based on Shingo’s Single Minute Exchange of Dies (SMED) that suggests the conversion of internal setup operations to external operations. However, the conventional SMED approach – as proposed by Shingo – does not possess a systematic approach to accomplish this conversion. Thus, a new approach is proposed in order to aid the process engineers in implementing SMED. The proposed approach is based on the conventional SMED, but also it incorporates Multiple Criteria Decision-Making Techniques (MCDM) to the third implementation phase. The MCDM techniques used in this work are Analytical Hierarchal Process (AHP), Preference Selection Index (PSI) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). The proposed approach provides a systematic procedure for selecting the best setup technique among the available alternatives, and takes also into consideration other factors that affect the decision-making process; including: cost, energy, facility layout, safety, life, quality and maintenance. A real example of PVC industry is used to exemplify the approach. The results demonstrate the capability of the proposed approach in setup time reduction, which in turn will improve machines’ utilization, and increase the productivity and flexibility of the whole facility.     

Euro PM2007 congress and exhibition

Abstract

Threatened with bureaucratic over-regulation under the EU's newly enacted REACH legislation, and other competitive challenges, the large tonnage section of the European PM industry did not seem to be facing a rosy future as it met in the Ville Rose city of Toulouse. Nevertheless, the EPMA was seen as having a key role in moving the industry forward and resisting the pressures from the large end users, low cost (Asian) producers, and competing technologies. Europe still leads the world in the manufacture of hard materials, but China is expected to overtake Europe in tungsten carbide and diamond tools production within the next 3–5 years. European sales of metal injection moulded parts continue to grow strongly, doubling in value to E140 million between 1997 and 2003. PM research in Europe is very active, with 40 universities and institutes and over 500 researchers involved. These provided the large majority of the European presentations at PM2007.     

短程硝化反硝化生物脱氮技术的探讨

短程硝化反硝化技术是将硝化反应控制在亚硝酸盐阶段,不进行亚硝酸盐至硝酸盐的转化,直接进行反硝化反应。文章阐述了短程硝化反硝化的形成机理,理论研究进展,系统介绍了短程硝化反硝化影响因素与控制分析,并探讨了短程硝化反硝化生物脱氮技术需深入研究的要点     

酯化法合成丙酮酸乙酯的研究

论述了以丙酮酸、乙醇为原料,离子交换树脂作催化剂,催化合成丙酮酸乙酯的新工艺。考察了催化剂种类、用量、原料配比、反应时间以及催化剂使用次数等因素对酯化率的影响,确定了催化剂种类和最佳工艺条件。结果表明,732强酸性离子交换树脂具有良好的催化活性和选择性,可多次重复使用,酯化率可达85.7%,产品质量符合国家标准。     

液相法合成氢化铝钠的研究

以NaH和AlCl3为主要原料,通过改变实验条件,探索研究液相法合成NaAlH4的合成条件。实验表明,在不加入任何催化剂的情况下无法实现NaAlH4的合成,在以NaAlH4、三乙基铝等物质为催化剂的条件下,虽有少量的产物生成,但是反应不明显,且产物中存在大量的非晶态物质。即便在高温高压下反应亦难以进行,大量的化合物均以非晶态形式存在。