天然高分子/水性聚氨酯复合材料制备和研究进展

介绍了水性聚氨酯与天然高分子的共混或将天然高分子的活泼氢基团与异氰酸根基团反应制备嵌段性高分子复合材料,通过选择合适的复配比例,可以提高天然高分子的力学性能,又可获得水性聚氨酯的可降解性。对天然高分子/水性聚氨酯相互配合制备复合材料的国内外最新研究进展进行了总结。     

Experimental Study on the Effect of Steel-fibre in Conerete Thick Cap

The effect of steel fibre used in concrete was systematically analyzed by model testing of 30 2-pile thick caps of steel-fibre reinforced concrete, in which the model scale was 1：5. The experiment system composed of a loading device, strain measurement system and a data-acquisition system was used, also an electromechanic centigrade scale, a lens and a Y J-25 static resistance strainometer were used.The experimental results show that the volumetric rate of steel fibre and draw ratio have an important influence on its load-bearing capacity. The incorporation of steel fibre can effectively improve the extension and reduce the thickness of the caps.     

电导率法快速甄别泔水油的研究

将泔水油溶于石油醚中,用水经搅拌浸提其中的导电物质,然后测定水相电导率.实验结果表明:石油醚加入量为油样量的2.5倍,去离子水加入量为油样量的2倍,超声振荡法搅拌5 min后分离油、水相测定水相电导率为最佳电导率测定条件.同时,在最佳条件下将泔水油与其他合格食用油的电导率进行对照研究,泔水油的电导率远远大于合格食用油的.泔水油掺入合格食用油中的电导率测定结果显示,泔水油的含量与电导率成正相关关系.因此,用水漫提后测定水相电导率可作为快速甄别泔水油的一种方法.     

二甲醚火焰传播速度的实验测定

二甲醚被誉为21世纪的绿色燃料，是目前理想的内燃机与民用替代燃料．为了获得二甲醚应用的重要基础参数——火焰传播速度，在定容球弹法、本生火焰法和平面火焰法作出比较分析后，采用本生火焰法实验测定了二甲醚火焰的传播速度．得出了二甲醚火焰传播速度与一次空气系数的关系曲线，并且在一次空气系数约为0．85处，二甲醚火焰传播速度的峰值为0．48m／s．     

补差集的构造

得到了q≡7（mod 16),q是素数幂时存在4－{q^2;q(q-1)/2;q(q-2)} 补差集的充分条件，给出了构造补差集的一种方法，构造出了q=7,23,71,151,167,199,263,359,439时的4-{q^2;q(q-1)/2;q(q-2)}补差集。     

不同类型 Y 分子筛粒子间的离子迁移及其应用

借助于ＸＲＤ、ＳＥＭ－ＥＤＳ和红外光谱等手段研究了在水热处理过程中不同类型Ｙ分子筛粒子间的离子迁移现象，证实这种迁移是可以发生的，并可促进分子筛晶胞的变化。由于ＲＥ＾２＋的迁移，用ＲＥＹ和ＨＹ分子筛复合制备的催化剂在裂化反应过程中表现出良好的活性和选择性。     

固定资产投资项目节能评估工作中存在的主要问题

一、固定资产投资项目节能评估的重要性 当今世界，能源已成为最关键的问题之一，能源是国民经济的命脉，对于社会、经济发展、提高人民生活质量以及国家未来生存安全都极为重要。改革开放以来，我国经济快速发展，社会对能源的需求也迅速增长，2001年-2009年社会总能耗量、万元GDP能耗量见表1。     

A submicron mild steel produced by simple warm deformation

One simple deformation process, through which a submicron ferrite grained mild steel was fabricated, was introduced. According to the transmission electron microscope images of the microstructures, most of the boundaries formed during the process might be low angle boundaries, which means that most of the ultrafine grains are subgrains. This deformation process is attractive because: (1) the necessary strain was only 1.5, (2) the deformation resistance decreased due to higher rolling temperature, and (3) the as warm-rolled mild steel had a microstructure with equiaxed grains of 0.7 μm in average diameter. The result of mechanical tests indicates that better properties, with comparison to its coarse-grained counterpart, were obtained, including doubled yield strength, high hardness, good work hardening and reliable elongation. Cross effect was observed during tensile process and interpreted from point view of conventional dislocation movement.     

用双自准直仪测量静态测角分度误差

介绍一种用双自准直仪和多齿分度强组合测量静态测角分度误差的测量方法。     

镁铝尖晶石粉体的制备方法

概述国内外关于镁铝尖晶石粉体的制备方法及这些方法的优缺点和适用范围,并将其归为固相法、湿化学法和燃烧合成法3类。分析表明,镁铝尖晶石的制备方法趋向于复合化,即集合两种或两种以上的方法来制备,以实现镁铝尖晶石粉体的高性能、高产量,同时满足传统产业和高技术领域的需求。