Plastic fats with zero trans fatty acids by interesterification of mango,mahua and palm oils

Speciality plastic fats with no trans fatty acids suitable for use in bakery and as vanaspati are prepared by interesterification of blends of palm hard fraction (PSt) with mahua and mango fats at various proportions. It was found that the interesterified samples did not show significant differences in solid fat content (SFC) after 0.5 or 1 h reaction time. The blends containing PSt/mahua (1:1) showed three distinct endotherms, indicating a heterogeneity of triacylglycerols (TG), the proportions of which altered after interesterification. The SFC also showed improved plasticity after interesterification. Similar results were observed with other blends of PSt/mahua (1:2). These changes in melting behavior are due to alterations in TG composition, as the trisaturated‐type TG were reduced and the low‐melting TG increased after interesterification. The blends containing PSt/mango (1:1) showed improvement in plasticity after interesterification, whereas those containing PSt/mango (2:1) were hard and showed high solid contents at higher temperature and hence may not be suitable for bakery or as vanaspati. The blends with palm and mahua oils were softer and may be suitable for margarine‐type products. The results showed that the blends of PSt/mahua (1:1, 1:2) and PSt/mango (1:1) after interesterification for 1 h at 80 °C showed an SFC similar to those of commercial hydrogenated bakery shortenings and vanaspati. Hence, they could be used in these applications in place of hydrogenated fats as they are free from trans acids, which are reported to be risk factors involved in coronary heart disease. For softer consistency like margarine applications, the blends containing palm oil and mahua oil are suitable.     

塑料啤酒瓶开发现状

介绍了塑料啤酒瓶的优点,详细介绍了各种以PET为基础的改性啤酒瓶材料,并列举了大量的开发实例。     

基于神经网络和遗传算法的薄壳件注塑成型工艺参数优化

建立了基于神经网络和遗传算法并结合正交试验的薄壳件注塑成型工艺参数优化系统。正交试验法用来设计神经网络的训练样本，人工神经网络有效的创建了翘曲预测模型；遗传算法完成了对影响薄壳塑件翘曲变形的工艺参数（模具温度、注射温度、注射压力、保压时间、保压压力和冷却时间等）的优化，并计算出了它们的优化值。按该参数进行试验，效果良好，可以有效地减小薄壳塑件翘曲变形，其试验数值与计算数值基本相符，说明所提出的方法是可行的。     

Oil thermal annealed nano‐structured indium tin oxide thin films for display applications

Indium tin oxide‐coated thin films (200 nm) are deposited on glass substrates by using R.f. sputtering technique. Here, we investigate the influence of new technique of treatment, which is called as “oil thermal annealing” on the nano‐structured indium tin oxide thin films at fixed temperature (150 °C) which improves adhesion strength, electrical conductivity and optical properties (transmittance) of the films. Oil thermal annealing is used to reduce inherent defects that may be introduced during the prepared thin film and cooling processes. Proposed technique is highly suitable for liquid crystal displays, solar cells and organic light emitting diodes, and many other display‐related applications.     

高压玻璃钢管漏失原因、处理方法及防治措施

玻璃钢管具有质量轻、承受压力高、耐腐蚀、不易结垢、施工简便、使用寿命长的优点。从2000年起,江汉油田将高压玻璃钢管线广泛应用于注水系统和污水处理系统,收到了良好的效果。在生产过程中,由于受外部损伤、施工质量、玻璃性能等因素的影响,漏失现象时有发生。针对这种情况,可采取切割造锥,利用钢制转换接头连接、管沟回填等措施进行解决,以规范施工工艺,保证质量和安全生产。     

Impact fracture behavior of clay-reinforced polypropylene nanocomposites

The micromechanism of plastic deformation during impact loading of polypropylene-clay nanocomposites is examined and compared with the unreinforced polypropylene under identical conditions of processing to underscore the determining role of clay. The addition of clay to polypropylene increases the impact strength in the temperature range of 0 to +70 °C. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and transmission electron microscopy (TEM), wide-angle X-ray diffraction (WAXD) and scanning electron microscopy (SEM) techniques provided an understanding of the micromechanism of plastic deformation in terms of the response of the polymer matrix, nucleating capability of the reinforcement, crystal structure, percentage crystallinity, lamellae thickness, and particle-matrix interface. The enhancement of toughness on reinforcement of polypropylene with nanoclay is associated with change in the primary mechanism of plastic deformation from crazing and vein-type in neat polypropylene to microvoid-coalescence-fibrillation process in the nanocomposite.     

Catalytic degradation of waste polyolefinic polymers using spent FCC catalyst with various experimental variables

Liquid-phase catalytic degradation of waste polyolefinic polymers (HDPE, LDPE, PP) over spent fluid catalytic cracking (FCC) catalyst was carried out at atmospheric pressure with a stirred semi-batch operation. The effect of experimental variables, such as catalyst amount, reaction temperature, plastic types and weight ratio of mixed plastic on the yield and accumulative amount distribution of liquid product for catalytic degradation was investigated. The initial rate of catalytic degradation of waste HDPE was linearly increased with catalyst amount (4-12 wt%), while that was exponentially increased with reaction temperature (350-430 ‡C). Spent FCC catalyst in the liquid-phase catalytic degradation of polymer was not deactivated fast. The product distribution from catalytic degradation using spent FCC catalyst strongly depended on the plastic type. The catalytic degradation of mixed plastic (HDPE: LDPE: PP: PS=3: 2: 3: 1) showed lower degradation temperature by about 20 ‡C than that of pure HDPE.     

Rockburst mechanism in soft coal seam within deep coal mines

A number of rockburst accidents occurring in soft coal seams have shown that the rockburst mechanism involved in soft coal seams is significantly different from that involved in hard coal seams. Therefore, the method used to evaluate rockburst in hard coal seams is not applicable to soft coal seams. This paper established an energy integral model for the rockburst-inducing area and a friction work calculation model for the plastic area. If the remaining energy after the coal seam is broken in the rockburstinducing area is greater than the friction work required for the coal to burst out, then a rockburst accident will occur. Mechanisms of ‘‘quaking without bursting" and ‘‘quaking and bursting" are clarified for soft coal seams and corresponding control measures are proposed as the optimization of roadway layouts and use of ‘‘three strong systems"(strong de-stressing, strong supporting, and strong monitoring).     

人眼屈光度校正算法的研究现状

人类能够与用户图像界面进行交互是依赖于一个清晰正常的视觉。然而,屈光不正（例如近视、远视、散光等）能使人眼视网膜中所显示的图像质量退化。图像质量的好坏严重影响了我们在军事、医学、娱乐领域所取得的研究成果。目前,对于人眼屈光度校正算法的研究主要有五种方法：1.应用一个维纳滤波的预补偿算法来校正人眼屈光度;2.用一个全变差的方法绘制图像对人眼屈光度进行校正;3.用视觉分析系统来校正人眼屈光度;4.使用多层显示器来校正视觉畸变;5.使用可计算的光场显示器来校正视觉畸变。通过研究这几种算法的优缺点提出现有算法的改进以及新的算法研究。     

粉末烧结体镦粗致密与成形的有限元分析

选择典型的镦粗工艺对粉末烧结坯的致密与成形行为和规律进行了研究，提出了多孔材料的致密模型并简要介绍了多孔材料的塑性理论。然后，采用有限元法模拟了不同镦粗压下量的烧结坯的致密与成形过程。密度与等效应变分布的一致性表明，烧结坯的致密强烈依赖于材料的塑性变形。