聚醚改性硅油乳化剂的合成及其在特种有机硅消泡剂中的应用

以端烯丙基聚醚F6、含氢硅油为原料,氯铂酸为催化剂,甲苯为溶剂,合成出聚醚改性硅油(PMS),并用红外光谱对其结构进行表征。正交实验优化合成条件为:原料中Si—H与CC的量之比为1∶1.2,催化剂用量为30×10-6,反应温度100℃,甲苯质量分数30%,该条件下反应3 h,含氢硅油中Si—H的转化率达98.7%。将其与白炭黑、甲基硅油等复配,制得粒径小、分布范围窄、球状颗粒的消泡剂。该乳液在65℃下贮存稳定,在高温、不同pH值(2～13)条件下不分层、不漂油,且能保持消泡速度快、抑泡活性强的特点。在PMS用量为起泡液质量的0.06%,鼓泡速度为3.0 L/min条件下,消泡剂可在5.5 s内使高度为500 mL的泡沫迅速破裂,抑泡时间长达1 510 s。     

浸入式水深监测仪器的设计

浸入式水深监测仪器,主要是利用压力传感器进行水深测量,将测出的电流信号转换成电压信号,再经过A/D转换,变成数字信号送入单片机中进行运算处理,最后通过通讯传输,U盘存储数据,液晶显示以及报警控制来完成整个仪器的设计.     

Enhanced photocatalytic hydrogen evolution based on efficient electron transfer in triphenylamine-based dye functionalized Au@Pt bimetallic core/shell nanocomposite

An efficient photocatalytic hydrogen evolution system based on triphenylamine-based dye functionalized bimetallic Au@Pt core/shell nanocomposite (Au@Pt-TPAD) was reported. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV–vis absorption spectra suggested that Au@Pt-TPAD nanocomposite consisted of a bimetallic nanoparticle with Au core and Pt shell nanostructure. The photoelectrochemical result suggested that photoinduced electrons could efficiently transfer from the triphenylamine derivative molecules to the bimetallic nanoparticles. Photocatalytic results showed that the Au@Pt₂-TPAD bimetallic nanocomposite could be used as a stable photoinduced H₂ evolution photocatalyst. Compared with the monometallic counterpart (Au-TPAD or Pt-TPAD), the bimetallic nanocomposite showed much higher catalytic activity for the photocatalytic hydrogen evolution. The amount of hydrogen evolution on the optimal catalyst under 12 h UV–vis light irradiation was about 37.5 μmol. The enhancement of the photocatalytic activity might be attributed to the synergistic effect between the two metals in bimetallic nanoparticles with core/shell structure. This investigation might open up new opportunities for the development of dye functionalized heterometallic nanocomposite with enhanced photocatalytic performance.     

铁强化剂对豆奶粉的感官影响研究

考察了3种铁营养强化剂对豆奶粉感官和酸度等理化指标的影响。通过"三点检验"试验表明,添加乙二胺四乙酸铁钠(NaFeEDTA)的豆奶粉和没有添加铁强化剂的豆奶粉在感官上没有显著差异,而添加了乳酸亚铁和硫酸亚铁的奶粉,却存在显著差异。采用"量值估计法"对添加NaFeEDTA、乳酸亚铁、硫酸亚铁的豆奶粉进行评分表明,3种铁强化剂对无糖和含糖豆奶粉的外观颜色、组织状态和冲调性无显著影响,含NaFeEDTA豆奶粉在气味、滋味方面的感官评价得分要明显高于乳酸亚铁和硫酸亚铁。通过理化检测发现,各种铁强化剂对豆奶粉的酸度和含水量几乎无影响。     

基于有限元仿真的IGBT混合模块的可靠性分析

集成化与微型化是当今电子信息产业发展的特点,其中电子元件的结温与热应力是影响其可靠性的重要因素。硅基IGBT和SiC基续流二极管组成的混合模块广泛应用于城市轨道交通等领域,其可靠性直接影响轨道交通车辆的运行性能。本文建立IGBT混合模块的仿真模型,随着各层材料厚度、焊料空洞大小和位置的变化,计算分析IGBT混合模块的温度与应变变化规律,对模块封装结构进行优化设计。将高热导率石墨烯应用在IGBT混合模块中,仿真分析应用位置不同对模块可靠性的影响,从而进一步优化混合模块的封装结构。通过仿真计算,优化后的IGBT混合模块可将最高结温降低近3℃,最大热应力下降超过30 MPa。     

汪友棠浅绛彩瓷版画赏析及其艺术成就

黟县籍画家汪友棠作的浅绛彩瓷绘右军潇洒出风尘瓷版,从了解瓷版画中的人物故事入手,欣赏浅绛彩瓷名家的画中意境,领略浅绛彩瓷绘名家汪友棠瓷绘的艺术风格和艺术成就,为研究徽学,特别是研究黟籍画家在当年景德镇形成绘瓷的一个画派提供了史料。     

阀门扭矩和弯矩连续测试装置及其检测方法

介绍了阀门扭矩弯矩连续测试装置及其检测方法的性能特点、图示说明及测试方式。给出了通过传感器测试阀门的扭矩和弯矩变化将模拟数据转换成数字信号并由计算机控制输出的工作过程。     

Cathodic electrochemiluminescence behavior of norfloxacin/peroxydisulfate system in purely aqueous solution

A novel cathodic electrochemiluminescence (ECL) behavior of the norfloxacin (NFLX)/peroxydisulfate (S₂O₈²⁻) system in purely aqueous solution at a glassy carbon electrode (GCE) was firstly reported in this paper. The NFLX/S₂O₈²⁻ system could produce a very strong ECL signal under the potential scan from 0 to −1.8 V in 0.1 M phosphate buffer solution (pH 7.0) containing 0.24 mg/mL NFLX and 10 mM S₂O₈²⁻, which was about 350 times higher than that of S₂O₈²⁻ alone, while NFLX did not produce ECL in the absence of S₂O₈²⁻. The effects of pH value, S₂O₈²⁻ and NFLX concentration on the ECL intensity were investigated and the possible mechanism for the ECL behavior of NFLX/S₂O₈²⁻ system was proposed.     

洋葱的成分及保健功能的研究进展

为了促进洋葱的开发利用,介绍了洋葱所含的化学成分和功效成分主要有含硫化合物、前列腺素A、洋葱类黄酮、硒、洋葱油树脂、苯丙素酚类和甾体皂苷类等,同时综述了其具有抑菌、降血脂、降血糖、抗血栓、抗肿瘤和抗氧化等保健功效,认为洋葱是一种具有较高的食用和药用的植物资源.     

基于Moldflow的手机电池盖浇口位置选择

首先对手机电池盖的结构进行分析,选择了两种浇口位置,并据此设计了2种浇注系统.然后采用Moldflow软件分别从充填时间、流动前沿处温度、体积收缩率等方面对这两种浇注系统进行注塑成型分析和比较,最终确定了最佳浇注方案和最佳浇口位置.