聚乙烯催化剂用烷氧基镁载体的研究进展

基于烷氧基镁载体的Ziegler-Natta聚乙烯催化剂具有活性高、氢调性能好等优点,是目前聚烯烃工业中的研究热点。介绍了烷氧基镁载体的发展进程,综述了烷氧基镁载体的制备及改进方法,分析了烷氧基镁载体在催化剂制备过程中的作用,并对开发适用于乙烯聚合的烷氧基镁载体提出了展望。     

涂装车间节水方案企划与实施

某涂装车间在现有节水措施的基础上，通过企划与实施一系列新的技术及精益管理措施，如，磷化出槽喷淋工艺优化、纯水制水率提升、空调冷凝水回用率提升、中水深度处理回用、用水分级管理等，将新鲜水用量从 15. 2 L/m2降至 11. 3 L/m2，达到涂装行业清洁生产评价指标体系（ 2016版）中的 I级标准 12 L/m²要求，处于国内领先水平。     

VUV photoluminescence properties of KSrPO4:Dy3+ phosphor

White-light-emitting phosphors based on phosphate host matrix, KSrPO_4 doped with Dy~(3+), were prepared by solid state reaction and their VUV luminescent properties were firstly investigated. The excitation band peaking at 125-153 nm corresponding to the absorption of PO_4~(3-) group exhibits very strong absorption. The phosphors emit warm-white luminescence under vacuum ultraviolet excitation of 147 nm, which consists of three main emission peaks located at 475, 570 and 662 nm, respectively.According to the luminescence and color chromaticity of the optimal sample KSrPO_4:1 mol%Dy~(3+),1.3 mol%Li~+, it can be a potential candidate for mercury-free fluorescent lamps.     

基质囊泡及其在骨矿化过程中的作用

基质囊泡(Matrix vesicles,MVs)是骨矿物初始形核生长的场所。骨矿化过程中,钙、磷酸根等离子经通道蛋白跨膜运输进入MVs内,当局部浓度达到一定值时,磷酸钙晶体开始沉积。磷酸钙的存在形态包括无定形磷酸钙、磷酸八钙及羟基磷灰石等。MVs可以调节细胞内外基质中的钙和磷酸根离子的稳态及无机磷酸盐/无机焦磷酸盐的比值,提供磷酸钙晶体成核位点,在骨矿化的初始启动过程中发挥重要作用。本文概述了MVs的生物来源、分子组分、提取方法,MVs介导的骨矿化过程,以及近年来利用囊泡作为体外矿化模型模拟MVs矿化过程的研究进展。     

Physicochemical characteristics,antioxidant capacity and thermodynamic properties of purple-fleshed potatos dried by radio frequency energy

Abstract

The impacts of using radio frequency (RF) energy to dry purple-fleshed potatoes were investigated and compared to infrared radiation (IR) and microwave (MW) drying techniques. The gelatinization rate, color, flavor, morphological, and structural characteristics, thermodynamic properties, as well as antioxidant capacity were examined. The results indicated that the drying time of RF (70?min) and MW (21?min) were shorter than IR (105?min). The gelatinization ratio of MW, RF, and IR were 94.4?±?2.0, 88.3?±?1.4, and 64.5?±?1.1%, respectively. The degree of crystallization of purple-fleshed potato powder decreased with all three drying methods. RF-dried potatoes were able to retain higher polyphenols (loss rate: 4.3%), total anthocyanin (3.7%), and total flavonoid content (35.1%), whereas IR showed the lowest retention. The content of polyphenols also decreased significantly. Furthermore, after RF heating, the scavenging of free radicals was higher compared to MW and IR.     

OMS-2催化剂成型工艺研究及其在印染废水处理中的应用

以OMS-2粉体催化剂为基础,对催化剂进行挤出成型,考察粘结剂种类、粘结剂用量、润滑剂和孔结构改进剂用量、焙烧温度对成型催化剂机械强度的影响。得到最佳成型工艺条件为,粘结剂硅溶胶用量为OMS-2粉体催化剂质量的105%～110%、辅助粘结剂纳米ZrO_2用量为OMS-2粉体催化剂质量的30%～35%、润滑剂田菁粉用量为OMS-2粉体催化剂质量的2. 5%～3. 0%、孔结构改进剂柠檬酸用量为OMS-2粉体催化剂质量的5%～6%,焙烧温度450℃。成型后催化剂机械强度可达150 N·cm~(-1),满足工业化应用对催化剂强度的要求。将成型催化剂应用于催化湿式氧化印染废水处理,经过432 h活性评价时间,COD平均去除率约91. 6%,反应结束后催化剂结构完整,平均机械强度约144 N·cm~(-1),表现出良好的水热稳定性。     

基于电能质量约束的智能配电网分布式电源消纳能力研究

针对智能配电网分布式电源消纳引起的电能质量问题，分析了以电能质量综合指标为控制目标的分布式电源消纳能力评价方法，并依此为约束，采用参数辨识的方法开展智能配电网分布式电源消纳能力研究。IEEE 33节点算例结果表明，文章提出的思路和方法可行，该方法可方便应用到实际工程的决策中。     

Multi-objective layout optimization for an orbital propellant depot

Structural and Multidisciplinary Optimization - The overall layout optimization design of an orbital propellant depot involves the optimization of shape, size, and positions of propellant tanks in...     

耐冲击型金刚石圆锯片锯切受力的数值模拟——以钥匙孔水槽底孔中镶铜钉的锯片为例

建立耐冲击型金刚石锯片锯切受力的有限元分析模型，围绕传统钥匙孔水槽和钥匙孔水槽的底孔中镶铜钉的2种齿形结构，以数值模拟的方式对比研究其锯切受力。仿真结果表明:在承受相同载荷的情况下，钥匙孔水槽底孔中镶铜钉锯片较传统钥匙孔水槽锯片在锯切受力时的变形、应力方面都得到了明显改善，其变形量减少6.36%，第一、第三主应力分别降低38.04%和41.36%。在钥匙孔水槽的底孔镶入铜钉的方式可以提高锯片的耐冲击性，适用于更大载荷的应用场景。