静电除尘设备原理及常见故障举例分析

阐述静电除尘器的原理、结构,根据设备在生产实际中的运用,总结静电除尘器在运行中经常出现的故障,包括机械、电气、运行不稳定等方面造成的故障,对故障原因进行了分析,提出适当的解决方法和预防措施.     

医用手套和检查手套新标准即将实施

国家标准化管理委员会2006年3月发布了GB 7543-2006《一次性使用灭菌橡胶外科手套》和GB 10213-2006《一次性使用医用橡胶检查手套》两项新标准,为了方便企业产品注册及产品与新标准的转换,决定在2007年7月1日开始实施。     

油页岩改性沥青微观机理与性能分析

采用荧光显微镜实验研究油页岩改性沥青的微观结构,通过流变实验(DSR)测试高、低温对其流变性能影响,利用沥青三大性能指标实验、粘度实验和旋转薄膜加热实验分析油页岩改性沥青的路用性能。结果表明,油页岩的添加能让SBS改性剂与基质沥青达到更好的共融状态,且能有效提高SBS改性沥青的高温稳定性、粘附性和抗老化性能,但会降低其低温抗裂性能;DSR实验表明掺入适量油页岩能明显提升复合改性沥青的复数剪切模量和车辙因子,且油页岩矿粉掺量越多,增幅越大。     

浅析我国乳胶手套市场前景及对策

<正>在胶乳制品中,乳胶手套占有很重要的地位。本文中的乳胶手套主要指检查手套和医用手套两类。20世纪80年代以来,随着人类免疫缺陷性病毒     

天然胶乳手套蛋白质过敏问题及对策

介绍了天然胶乳手套中所含蛋白质的种类、胶乳蛋白质过敏的起因和流行情况,指出过敏反应与胶乳中的可抽提蛋白质含量有关,采用沥滤、超声波技术与沥滤结合、多次离心胶乳、手套表面氯化处理、酶处理和辐射工艺可降低胶乳手套中的可抽提蛋白质的含量。     

有机蒙脱土增强聚氯乙烯手套材料的制备与表征

通过在乳液聚氯乙烯（PVC）中添加有机蒙脱土（OMMT）来研究OMMT对其各项性能的影响。结果表明：OMMT对乳液PVC／邻苯二甲酸二辛酯（DOP）／OMMT纳米复合材料的力学性能有一定的改善效果;对复合材料的抗增塑剂迁移效果明显;在耐酸和耐碱试验中,未添加OMMT的复合材料的拉伸强度和撕裂强度分别降低了7．3％、5．i％和5．5％、13．3％,而添加3份OMMT后,仅仅降低了2．5％、2．6％和1．5％、4．2％,效果显著。     

Geometric analysis of dielectric failures in polyimide/silicon dioxide nanocomposites

Polyimide/silicon dioxide nanocomposites were tested for their dielectric strength against nanofiller concentrations between 0% and 14%. The sol–gel process was used for in situ generation of silicon dioxide nanoparticles in a polyamic acid host matrix. Spin‐coated and imidized samples with approximately 15 μm in thickness were then subjected to dielectric breakdown measurements in accordance with ASTM standards. Results showed two distinct regimes of dielectric strength. Higher dielectric withstand capability of nearly 275 kV mm^?1 was exhibited by samples with 0% and 2% silicon dioxide. Higher concentration samples were dielectrically weaker by approximately 45% at 150 kV mm^?1. Broken‐down specimens were examined under optical and electron microscopes. An inverse relationship between nanoparticle concentration and breakdown perforation diameter was observed. Hole sizes decreased gradually from 140 to 40 μm as silicon dioxide content increased from 0% to 6% and ultimately settled near 30 μm with higher concentrations. The testing results, examined through failure analysis, were explained by breakdown behaviors and mechanisms at different size scales. The findings from this project, in context with previous works and theories, can help establish connections of dielectric strength, perforation diameter, and nanofiller concentration for future polymer nanocomposite research. POLYM. ENG. SCI., 59:1897–1904, 2019. © 2019 Society of Plastics Engineers     

Microscopic and electrochemical characterization of lead film electrode applied in adsorptive stripping analysis

Lead film electrodes (PbFEs) deposited in situ on glassy carbon or carbon paste supports have recently found application in adsorptive stripping voltammetric determination of inorganic ions and organic substances. In this work, the PbFE, prepared in ammonia buffer solutions, was investigated using scanning electron microscopy, atomic force microscopy and various voltammetric techniques. The microscopic images of the lead films deposited on the glassy carbon substrate showed a considerable variability in microstructure and compactness of the deposited layer depending on the selected experimental conditions, such as the concentration of Pb(II) species, the nucleation and deposition potential, and the time applied. The catalytic adsorptive systems of cobalt and nickel in a solution containing 0.1 ammonia buffer, 2.5 × 10⁻⁵ M nioxime and 0.25 M NaNO₂ were employed to investigate the electrochemical characteristics and utility of the in situ prepared lead films.The optimal parameters, i.e. the lead concentration in the solution, the procedure of film removal, and the time and potential of lead nucleation and film deposition for the adsorptive determination of metal traces, were selected, resulting in the very good reproducibility (RSD = 4.2% for 35 scans) of recorded signals. The voltammetric utility of the lead film electrode was compared to that of glassy carbon, mercury film and bismuth film electrodes, and was subsequently evaluated as superior.     

丁腈胶乳640应用于生产薄型一次性手套

用羧基丁腈胶乳进行了薄型手套的试制实验,对胶乳的成膜性能、干燥条件、氧化锌的用量进行了研究,结果表明,通过添加成膜助剂,控制干燥温度,确定氧化锌用量及应用补强剂,能够克服羧基丁腈胶乳湿凝胶强度低、收缩大、成膜性差的缺点,制作出外观漂亮、性能优良的手套。     

涂装车间PVC机器人喷涂系统的工作原理及典型故障解析

以杜尔全自动机器人PVC胶喷涂系统为对象,详细阐述了PVC喷涂系统的工作原理、校准方法和喷涂质量监控过程.针对由阀岛卡顿导致的喷涂中断典型故障进行了分析并提出了改进措施.总结了杜尔PVC喷涂系统可能存在的风险及后续的完善方向.     

Microscopic analysis of the wood bond line using liquefied wood as adhesive

The bonding of beech (Fagus sylvatica L.) with liquefied wood (LW) causes deterioration of the wood surface, resulting in a high percentage of wood failure at a relatively low bond shear strength. Light microscopy, scanning electron microscopy, FT-IR micro-spectroscopy and elemental carbon, nitrogen and sulphur (CNS) analysis techniques were used to investigate the formation of such bonds. It was assumed that the degradation of lignin, hemicelluloses and parts of the cellulose occurred in the cells of the wood surface where the LW had been applied. At the elevated temperatures occurring during the bonding process, the deteriorated cells were carbonised to some extent. The weak boundary layer of the bond was determined to be a layer of delignified cells located between the zone of partly carbonised cells on the one side and the cells of the undamaged wood of the adherend on the other side. The bonds which formed during the bonding of wood with LW were found to be very untypical compared to bonds formed by synthetic wood adhesives. No adhesive film was formed, the adhesive-adherend interface was not clear and the cells of the adherend subsurface were damaged.     

乳胶手套表面弱酸涂层的性能

研究了弱酸涂层的性能及其对弱酸涂层乳胶手套的影响效果,探讨了弱酸与乳胶手套的结合机理、弱酸在手套表层的均匀分布及其存在形式。结果表明,弱酸涂层在手套表面扩散、吸附、黏结,弱酸与乳胶以机械嵌合形式或扩散吸附形式相结合。羧甲基纤维素/羟乙基纤维素黏合剂和聚环氧乙烷衍生物添加剂对弱酸在乳胶手套表面的黏结和分散有良好的作用。     

橡胶医用手套生产工艺对其绝缘性能的影响

通过实验分析了影响橡胶医用手套绝缘性能的有关因素，列举了相关的实验数据，实验结果表明：手套的表面类型、手套生产过程的工艺控制对绝缘性能影响很大。     

Swelling of polymeric glove materials during permeation by solvent mixtures

Extrapolation from permeation data for pure solvents does not predict accurately their behavior in mixtures. In this study we examined whether the permeation of natural rubber, nitrile, and PVA glove materials by solvent mixtures is proportional to material swelling. Gloves were exposed to solvent mixtures and their permeation was monitored: breakthrough times, permeation rates, and degree of swelling were determined. Toluene exhibits higher permeation than MEK through natural rubber. Adding MEK to toluene decreased the permeation of toluene and increased that of MEK, proportionally to mixture composition and the degree of swelling. The opposite was observed for nitrile: toluene, now the “low permeation” solvent (LPS), retarded MEK permeation and vice versa. The effect was proportional to mixture composition but not consistently proportional to the degree of swelling. Samples were also exposed to the LPS for different time periods prior to a permeation run using the “high permeation” solvent (HPS). The decrease in breakthrough time of the HPS was proportional to the degree of swelling caused by the LPS. Material swelling appears to control MEK and toluene permeation through natural rubber. For nitrile, additional factors are apparently at work. No permeation was detected through PVA and material swelling was negligible. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 775–783, 2005     

Microscopic effects on chloride diffusivity of cement pastes—a scale-transition analysis

For estimation of the durability of structures, it is highly desirable to quantify and simulate the chloride diffusion process in concrete. To this end, diffusion–cell experiments delivering the chloride diffusivity of cement pastes with different water–cement ratios (related to different microporosities) are evaluated in a scale-transition analysis. For prediction of the apparent chloride diffusivity, cement paste can be modelled by means of a differential homogenization scheme involving nondiffusive spherical inclusions in a diffusive matrix. As a result, chloride diffusivity of cement paste is obtained as a function of the microporosity and the chloride diffusivity in the micropore solution. Remarkably, the latter turns out to be one order of magnitude smaller than the chloride diffusivity in a pure salt solution system. The smaller diffusivity is probably caused by structuring of water molecules along the pore surface of cement paste.     

微生物浸出反应硫化铜矿石表面形态特征显微分析

通过光学显微镜和电子显微镜分析了硫化铜原矿样和经摇瓶浸出反应后的矿样表面形态变化特征.结果表明:两个矿样的铜的浸出率、TFe离子质量浓度均随着浸出逐渐上升,粒径较小的矿样浸出率较大.未经浸出反应的原矿样表面比较平整,微观尺度上的孔隙、孔洞很少;浸出反应后,矿石表面吸附有大量细菌,表面变得凹凸不平,大量目的金属元素被浸出.     

碳化硅化学机械抛光中金刚石磨粒与二氧化硅磨粒作用的微观模拟分析

采用反应力场(ReaxFF)分子动力学方法模拟分别以金刚石磨粒和二氧化硅磨粒对碳化硅进行化学机械抛光时的表面微观行为,探讨了这2种硬度不同的磨粒对碳化硅表面原子的去除机制.结果表明,二氧化硅磨粒在抛光过程中相比金刚石磨粒更容易发生化学反应,主要通过持续与碳化硅表面原子成键和断键来实现原子的去除.金刚石磨粒能够使碳化硅表...