矢量图的参数化重建系统——VACAD

本文重点探讨了如何将矢量图形进行参数化重建，即从只具备纯几何信息的矢量图中抽取元素间的拓扑信息，从而保证尺寸变动时保持拓扑关系不变，并能对多视图进行同步处理。这一方法的最大优点是用户作图时不受约束，因为系统只处理最终图形。另外，该思想并不局限于Ａｕｔｏ ＣＡＤ环境上，可方便地推广到其它二维绘图系统中。     

TiO_2粉体性能对PTC热敏电阻性能的影响

ＴｉＯ_２的纯度、粒度及粒形对ＢａＴｉＯ_３系ＰＴＣＲ的性能影响很大，对所用ＴｉＯ_２加以选择非常重要，国产和日本产ＴｉＯ_２原料在粉体性能上存在差异。     

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吐哈油田在总结国内成功经验的基础上，立足先进适用，配套可靠，相继在鄯善、温米、丘陵三大油田建成了鄯善１０＃、鄯善３０＃、温米５０＃、丘陵１２０＃轻烃回收装置，形成了２１０×１０４ｍ３／ｄ的处理规模。根据吐哈油田天然气的物理性质、压力、外输压力要求，采用低温分离法。在轻烃回收发展过程中，经不断完善和改进，现已形成燃气引擎往复式压缩机；分子筛脱水；多股流冷箱换热；重烃逐级降压闪蒸提馏脱水技术；丙烷制冷；膨胀机制冷；导热油供热；ＤＨＸ工艺；屏蔽液烃泵；分布式集散控制系统和安全联锁控制１０项关键技术。     

全局最小均方算法

本文提出了一种基于全局均方误差最小准则的全局最小均方（ＴＬＭＳ）算法，在理论上分析了它的统计特性和收敛性，用数字仿真技术优良地它的性能。     

油溶性减阻功能聚合物的研制

介绍了以混合α-烯烃为原料,制备了具有减阻功能的共聚物。讨论了催化剂浓度、聚合温度、预聚合时间、原料单体中杂质含量对共聚物特性粘度和转化率的影响。试验表明,在较低的催化剂浓度和预聚合温度下,能得到较高分子量的聚合物。气相色谱法和DSC法测定其组成和单体混合物的组成基本一致,表明共聚物是一种无规的梳状结构聚合物。该聚合物达到较高特性粘度时,能获得较好的减阻率。     

铌酸对酯化反应催化性能的研究

研究了新型固体酸催化剂铌酸对乙醇及异戊醇与乙酸酯化反应的催化性能、研究表明热处理温度对水洗法制备的铌酸催化剂的催化活性有显著影响,在350℃处理时活性达到极大值.与HZSM-5相比,铌酸催化剂不仅在乙醇和乙酸的气相酯化反应中表现出良好的催比性能,而且在异戊醇和乙醇的液相酯化反应中亦表现出较好的催化活性和稳定性.     

Statistical studies of branched ester latex and paint properties

Vinyl versatate, butyl acrylate and 2-ethylhexyl acrylate were compared as comonomer, for colloid-stabilized vinyl acetate latex polymers to assess their impact on latex coating properties. Vinyl versatate afforded advantages in scrub resistance, gloss, hydrophobicity and higher glass transition temperatures. Butyl acrylate developed better wet adhesion efficiency, gel content and hiding efficiency. 2-Ethylhexyl acrylate offered performance comparable to butyl acrylate in hiding efficiency, lowering copolymer glass transition temperatures, and gloss development. Combinations of these monomers, in many instances, afforded a better balance of performance properties than individual monomers alone. In the subject study, a simplex-centroid design was utilized to statistically map polymer compositions for determining the effect of comonomer composition on latex and paint film properties. In addition to developing contour maps of polymer and paint properties as a function of composition, a technique for studying structure-property relationships is presented.     

Some kinetic aspects of unsteady-state partial oxidation reactions. Dynamic processes on metal oxide surfaces

It is shown that steady-state kinetic data do not allow the discrimination between the redox and associated mechanisms of the partial oxidation reactions. A discrimination between these mechanisms was performed using transient experiments. The obtained rate expressions are in agreement with experimental kinetic data for catalytic partial oxidation of o-xylene.

An influence of the conjugate oxidation of a catalyst surface on dynamics and kinetics of the heterogeneous catalytic oxidative reactions is considered. Computing simulation of methane oxidative coupling of methane reaction at lowered temperature and elevated pressure has been performed. It showed that the reaction order with respect to oxygen exceeding unity is consistent with the chain branching mechanism of the reaction in the presence of TiSi₂ and TiB₂ and showed the important role of the branching chain cycles in the low-temperature OCM reaction at elevated pressure.     

提高铌钽标准液显色反应能力并延长其有效贮存期的分光光度法研究

铌，钽的酒石酸，柠檬酸，草酸铵标准液的显色反应能力及有效贮存期，同铌，钽的原始标准溶液ｐＨ有很大关系，铌酒石酸标准液（原始溶液ｐＨ１．４），其显色反应能力仅在８０％～５０％之间（视放置时间长短而异），但如何采用ｐＨ４．５～５．０的铌酒石酸标准液，其显色反应能力达１００％，即使贮存４４０ｄ后，仍能保持原有的显色反应能力，铌柠檬酸标准液（原始溶液ｐＨ１．２），无论用本法（Ｎｂ－ＢＰＲ－ＣＰＢ法）还是用