中性皂熔融法合成蔗糖酯的研究

本法以氢氧化钾和硬脂酸乙酯生成的脂肪酸皂为乳化分散剂，使蔗糖和硬脂酸乙酯在熔融物系中直接发生酯交换反应合成蔗糖酯。适宜的反应条件为：蔗糖：硬脂酸乙酯：氢氧化钾：碳酸钾（催化剂）的摩尔比为1：1．5：0．5：0．036；反应温度130℃，压力（1．33－9．33）×103Pa搅拌下反应4小时。所得粗产物的酯得率89．9％。     

Improved creaminess of low-fat yoghurt: The impact of amylomaltase-treated starch domains

Amylomaltase-treated starch (ATS) is an excellent creaminess enhancer in yoghurt. Small amounts of ATS raised the creaminess perception of low-fat yoghurt (1.5%) to that of full-fat yoghurt (5%). In this way, a reduction in fat-related energy value could be achieved from 45 to 21.5 kcal/100 g product. The functionality of ATS in set yoghurt resulted from discrete domains of ATS that resemble the microstructural behaviour of fat particles. The microstructure of the yoghurt is dominated by the protein and the ATS domains are enclosed in or bound to this protein network. The perceived creaminess resulted from in-mouth melting of these ATS domains due to a combined effect of their physical melting and hydrolysis by amylase present in the saliva.     

The Dependence of the Melting Temperature of Cobalt–Carbon Eutectic on the Morphology of its Microstructure

Fixed points provide a reliable way to realize and verify temperature scales. High-temperature fixed points are being developed based upon alloys, since single-phase materials are impractical to use above the copper freezing point. In particular, eutectic alloys have been shown to be sufficiently reproducible to warrant consideration as a way to significantly improve high-temperature metrology. However, eutectic alloys have certain characteristics requiring that they are used differently from the current ITS-90 fixed points. As their freezing temperature depends on the freezing rate, the melting temperature is preferred, though it has been shown that for some alloys, notably iron–carbon and cobalt–carbon, the apparent melting temperature can depend on the rate of the preceding freeze. This behavior will need to be explained and quantified if such fixed points are to be acceptable. The effect of varying the freezing rate on subsequent melting has been investigated for cobalt–carbon eutectic fixed points. The apparent melting temperature varies by up to 50 mK. Measurements were made of two different fixed-point blackbodies with very similar results. Optical microscopy of samples produced at different freeze rates shows a change in scale of the microstructure. Electron back-scatter diffraction (EBSD) shows evidence of high levels of residual strain in rapidly frozen samples. The effect of annealing on the melting behavior and microstructure has also been investigated. It is suggested that disordered phase boundaries and residual strain lead to changes in the melting behavior as nonequilibrium conditions may lead to a significant level of pre-melting. Whether this actually changes the liquidus temperature, or whether the melting temperature variation is due to the way the melting point is defined, is also discussed. The variation requires consideration if the highest accuracy is to be achieved, and will be a contributory factor to any uncertainty budget.     

(AgCu28)80InxSn(20-x)钎料的熔化特性及其铺展性研究

采用差示扫描量热仪研究了合金的熔化特性。结果表明：该合金在489～496℃处具有554～604℃两个明显的吸热带，添加11wt％的In时，其只存在496℃与603．6℃两个吸热峰。润湿与铺展性能测试表明该合金能很好地润湿紫铜，在In添加量大于12wt％时，随着In含量的增加铺展率变大。     

Y-△起动接线方式的改进

主要阐述传统Y-△起动接线的不足,通过改进接线方式,实现了Y接起动时降低流过KY接触器主触点的电流,并解决了因各种原因造成电动机Y接法所不能转换成△接,从而保证电动机安全、可靠的运行。     

Fabrication of amorphous bulk and multi-phase ceramics by melting method in the HfO2-Al2O3-Gd2O3-Eu2O3system

Ceramics have generally been fabricated from powders by shape forming & sintering methods except for glasses and glass ceramics. Glasses and glass ceramics can be fabricated by melting methods. The melting method has not only higher productivity but also higher shape forming ability than powder processes via forming & sintering methods. Thus we have reinvestigated melting methods in binary and ternary oxides systems to fabricate amorphous bulk ceramics and bulk nano composites. We have successfully fabricated amorphous phases by simple melt solidification methods in ternary eutectic melts in the HfO₂-Al₂O₃-Gd₂O₃system. The present study demonstrates the formation of the amorphous phases in quaternary systems HfO₂-Al₂O₃-Gd₂O₃-Eu₂O₃. Furthermore, we have also succeeded to fabricate nano-structured bulk ceramics, which consisted of constituent oxide grains with 20–100 nm in size, by post annealing of the amorphous phase.     

冲天炉气氛监控仪的研制与应用

本仪器以惠斯登电桥原理的热导式气体检测装置为主要部件，并附有连续抽气、过滤冷却和排除干扰气体的吸附装置等组成部分．它不仅能对熔炼全过程的炉气中ＣＯ２的成份进行准确而迅速地测量与显示，而且能通过排除干扰气体的测量，间接地测出气氛中氢气含量的多少．本仪器在生产实践中使用证明：炉气中ＣＯ２含量的相对变化与铁水过热温度有明显的对应关系，用本仪器所指示的ＣＯ２含量的变化规律对炉况进行监控是行之有效的手段．     

开孔型橡塑多孔材料的应力-应变行为

研究了拉伸应力对开孔型橡胶一塑料多孔材料形态结构和力学性能的影响。结果表明：拉伸应力的增加使橡塑多孔材料产生了形变，导致了气泡孔孔径、透水率的增大。不同定伸长率试样的回缩率是有差异的，定伸长愈大，试样的回缩形变就愈大；回缩形变随时间的变化主要发生在拉伸试样恢复期的初期，30d后试样的形变基本稳定。     

Reversible formation-melting of nano-crystals in supercooled oxyfluoride germanate liquids

The nanocrystals play a critical role in generating and affecting functionalities of glass materials. Therefore, scientists have made considerable efforts in clarifying microscopic mechanisms of nanocrystal formation in glass to obtain the desired type of nanocrystals. However, the phase transitions of nanocrystals during heating have not been well understood. Here we report on a discovery of the reversible melting-formation of nanocrystals in an oxyfluoride germanate glass during heating-cooling circles. Using a differential scanning calorimetry (DSC), we detected a striking endothermic event at 925 K during heating, after the glass underwent a DSC upscan to a temperature between 925–986 K and subsequent cooling. Based on Raman spectroscopy, X-ray diffraction and transmission electron microscopy, the endotherm is attributed to the melting of nano-crystal BaGeF₆ (˜20 nm). An exothermal response was observed at 890 K during the DSC downscan, implying the re-formation of BaGeF₆ nano-crystals. This suggests that the melting-formation of BaGeF₆ nano-crystals is a typical first-order transition.