橡胶减摆器的环境适应性研究

采用电液伺服试验机进行了橡胶减摆器高低温动态特性测试,研究了橡胶减摆器在不同温度环境下动态特性的变化规律,为其在高寒和热带地区的应用提供依据;同时对其湿热、霉菌和盐雾环境适应性进行了测试,为其在潮湿和海洋环境中的应用提供了依据。研究结果表明,当温度在-55~20℃之间时,橡胶减摆器的低温动态刚度与室温下的比值在1~1.7之间;当温度在20~70℃之间时,橡胶减摆器的高温动态刚度与室温下的比值在0.86~1之间;橡胶减摆器具有较好的高低温动态性能;湿热、霉菌和盐雾试验结果表明,橡胶减摆器的环境适应性优良。     

异丙基萘的分子间烷基转移及其在制备2,6-二异丙基萘中的应用

Isopropylation of naphthalene with propene resulted in a variety of isomers having different alkylation levels. The most important isomer is 2,6-DIPN, which is the precursor of important monomer 2,6-naphthalene dicarboxylic acid used for making liquid crystal polymers. In order to increase the yield of 2,6-DIPN, the intermolecular transalkylation with naphthalene was applied to the mixture of other DIPNs and PIPN to obtain MIPN enriched product, which underwent isopropylation with propene to produce 2,6-DIPN in a higher yield. The experimental study showed that the preferable conditions for transalkylation were reaction temperature of 325℃, the molar ratio of isopropyl group to naphthyl group （IP/N） of 0.8 ： 1-0.9 ： 1, reaction time of 4h and 5% of amorphous silica-alumina by mass. The conversions of DIPN and PIPN in its mixture were 62%-69% and 87%-88% respectively and the yield of MIPN was greater than 40%. The mixture of MIPN enriched product and recovered MIPN from rectification was subject to isopropylation with propene at 275℃ over a shape-selective catalyst to produce 2,6-DIPN in a yield up to 38%. A recycled process of recovered components was established, through one cycle the yield of 2,6-DIPN based on naphthalene may be 2.8 times higher than before, and the utilization ratio of raw naphthalene was increased by 46%.     

松香及其改性产品质量检验方法综述

介绍了松香及其改性产品的质量检验标准,针对其主要技术指标:颜色、酸值、树脂酸和金属离子含量的分析方法及研究现状进行了综述,并建议在国家标准中增加松香树脂酸和金属离子含量指标的检测方法.     

柠檬酸三丁酯、乙酰柠檬酸三丁酯合成工艺的研究

以柠檬酸、正丁醇为原料，采用直接酯化法合成了柠檬酸三丁酯。以柠檬酸三丁酯、乙酐和正丁醇为原料，采用共乙酰化-酯化法合成出乙酰柠檬酸三丁酯，并联产乙酸正丁酯。考察了催化剂用量、原料配比、反应温度、反应时间等因素对反应过程的影响，确定了较佳的操作条件，柠檬酸三丁酯收率≥98％，乙酰柠檬酸三丁酯收率≥98％。采用活性炭脱色技术对产品进行精制，明显改善了产品的色泽。     

Properties evaluation and fabrication of green clay reformulated from water sludge

Water sludge from Sungai Dua Penang fresh water processing plant has been successfully converted into functional pottery clay with improved physicochemical behavior and properties. Water sludge was generally made of kaolinite mineral that consisted of silica and alumina. At 7 h of milling duration, water sludge demonstrated a narrow particle size distribution at the size range of 107–150 µm. Water sludge owned a specific surface area of 27 m²/g with 8.8 nm (diameter) pore size and 0.05 cm³/g pore volume. Plasticity of clay body increased when clay formulation involved fine particles, e.g. water sludge or bentonite, which promote water adsorption ability. Fine particles with large surface area and better compaction also explained the enhanced hardness of pottery clay. The incorporation of clay minerals such as bentonite and sodium silicate into the formulation has facilitated metals immobilization within the clay body. Final clay product has a terra cotta color and performed a uniform shrinkage without obvious fracture. The fabrication of pottery wares from water sludge with minimized metals leakage has not only higher reutilize value but also a cost effective green method for handling waste and environmental issues.     

熔块中的气泡缺陷及其解决办法

分析了熔块生产中气泡缺陷产生的各种原因．提出了实际生产中的注意事项和具体的解决办法。     

Periodic nano/micro-hole array silicon solar cell

In this study, we applied a metal catalyst etching method to fabricate a nano/microhole array on a Si substrate for application in solar cells. In addition, the surface of an undesigned area was etched because of the attachment of metal nanoparticles that is dissociated in a solution. The nano/microhole array exhibited low specular reflectance (<1%) without antireflection coating because of its rough surface. The solar spectrum related total reflection was approximately 9%. A fabricated solar cell with a 40-μm hole spacing exhibited an efficiency of 9.02%. Comparing to the solar cell made by polished Si, the external quantum efficiency for solar cell with 30 s etching time was increased by 16.7%.     

复合材料单面双线缝合装置的设计

通过对复合材料的缝合技术和缝合特点的概述,发现目前双面缝合以及单面缝合技术存在的问题和不足,然后结合现有的OSS单面缝合和传统的双面锁式缝合技术的优点,提出了单面双线缝合技术,并基于该技术的缝合动作利用建模软件Solid Works对缝合装置进行了详细的设计,该技术对纤维复合材料铺层的缝合能够形成平滑稳定的类似改良式锁式线迹。最后通过Adams进行运动仿真,验证了各机构能够按规律配合完成缝合动作,证明了缝合装置设计的可行性。     

High‐Strength ZrC Ceramics Doped with Aluminum

High‐strength ZrC ceramics with relative density above 98% were prepared by reactive hot pressing of ZrC and Al at 1900°C. The reaction between ZrC and Al resulted in the formation of ZrC_1?x, Zr₃Al₃C₅ and Zr–Al compound such as AlZr₃ and Al–C–Zr. The intermediate product AlZr₃ below 1600°C and remained Al–C–Zr phase could form liquid phase and promoted the first stage of densification process. The improvement in densification behavior at higher temperatures (1800°C–1900°C) could be attributed to the formation of nonstoichiometric ZrC_1?x. Adding 5 wt% and 7.5 wt% Al to ZrC, the formed ZrC_0.85–Zr₃Al₃C₅ and ZrC_0.80–Zr₃Al₃C₅ based ceramics had 3‐point bending strength as high as 757 ± 79 MPa and 967 ± 50 MPa, respectively, with hardness and fracture toughness being 16.2–18.3 GPa and 3.3–3.5 MPa m^1/2, respectively.     

表面活性元素影响钢液脱氮动力学

在４０ｋｇ真空感应炉上进行表面活性元素（氧、硫）影响钢液脱氮动力学的研究，实验采用真空碳脱氧工艺，研究在不同的硫含量条件下，钢中脱氧和脱氮的相互关系．研究结果表明：（１）当钢中硫含量较低时，脱氮速率很快，随着硫含量的逐步增加，脱氮速率相应降低．（２）钢中硫含量较低时，脱氮速率快于脱氧速率；而当硫含量较高时，脱氧速率大于脱氮速率．（３）真空碳脱氧过程中，脱碳、脱氧速率与硫含量关系不大．