超声-臭氧氧化处理硝基苯废水实验研究

在实验装置上对超声-臭氧氧化处理硝基苯废水进行了实验研究，主要考察了废水初始pH值、反应时间，臭氧通入量、超声功率等因素对硝基苯去除率的影响，实验结果表明，超声辐射可以在臭氧氧化过程中起加速反应的作用，而且随着超声功率的增大，加速反应的能力增强；废水初始pH值为11时硝基苯去除效果最佳；随着臭氧通入量的增大，反应时间的延长，硝基苯去除率不断增大；超声-臭氧处理硝基苯废水过程中硝基苯的降解规律为表现一级反应。     

汽车塑料饰件电镀工艺及其性能检测

本文重点讲述了汽车塑料电镀工艺以及其可能存在的各种问题,进一步介绍了相关问题的解决方法.参照目前国际上各大整车厂的性能检测方法,论述了如何对汽车塑料电镀成品件进行性能测试来确定其质量.随着各国对环保要求的提高,希望我国汽车塑料电镀工艺能紧追和应用先进工艺,减少对环境的污染.     

地下水NH4+-15N同位素测试技术进展

本文根据铵离子的物理化学性质,建立了各种测试分析技术.传统的NH4+_-15N同位素测试过程包括样品中NH4+的收集、转化为适于质谱分析的气态N2以及用15N同位素质谱进行分析.其中NH:的收集方法较多,包括蒸馏法、扩散法、离子交换柱法和沸石萃取法等.适于质谱分析气态N2的转化方法可分为化学湿法和干燃烧法.笔者就同位素分析测试过程中NH4+的收集、转化及15N测试各个步骤加以总结,分析各自方法的优缺点和适用范围,寻求问题的解决途径.并评述了最近出现的色谱-质谱联合分析法和叠氮法.最后对地下水NH4+-15N同位素测试技术的发展进行了展望,以期能够更广泛地应用于环境和水文地质领域.     

能力验证的方案设计与实施综述

随着能力验证计划活动的广泛应用,能力验证活动的组织者在设计与实施能力验证计划方案过程中会遇到一些问题,本文试着从对一些共性问题进行分析及探讨,以期为今后的能力验证工作提供参考.     

Ultrasonic preparation of nano-nickel/activated carbon composite using spent electroless nickel plating bath and application in degradation of 2,6-dichlorophenol

Ni was effectively recovered from spent electroless nickel （EN） plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine- formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon （MFT/AG）. PdC12 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite （Ni/AC） in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electro- chemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2.6-dichloronhenol.     

电子产品虚拟试验评估技术综述

介绍了虚拟试验技术在电子产品评估鉴定中的应用方法。首先论述了虚拟试验技术产生的背景及其技术优势。然后结合国外的研究状况,重点对电子产品虚拟试验评估技术的基本流程和涉及的关键技术作了总结和归纳。最后,指出虚拟试验技术在电子产品评估中具有广阔的应用前景。     

总氮测定中应注意的几个问题

对总氮测定中影响空白值偏高的因素进行了实验和分析,并提出了改进意见。     

弹性滑移支座力学性能的试验研究

介绍了弹性滑移支座的原理、构造和特点;通过对其在不同工况下的性能试验,研究了竖向荷载、位移幅值以及加载频率对弹性滑移支座力学性能的影响,并给出了试验值与理论计算值之间的对比。研究结果表明:弹性滑移支座具有良好的工作性能,滞回曲线饱满,耗能能力强;竖向荷载和加载频率对弹性滑移支座的力学性能有一定的影响,而位移幅值对其影响较小;弹性滑移支座的恢复力模型,可以用考虑速度的指数摩擦力模型来描述,并且模拟得较为准确。     

Non-UV based germicidal activity of metal-doped TiO2 coating on solid surfaces

A stain-based screening method was developed to screen different catalyst coatings for their germicidal activity. A Baclight dead/live bacteria viability kit （invitrogen, molecular probes） was used for staining the cell. The screening was carried out following a standard procedure. This included loading cell suspension to solid surface and maintaining contact for 30 min, then staining with a mixture containing dyes. The stained cells were observed using an epifluorescent microscope and photographed with a CCD camera under UV. Metal-doped TiO2 coatings on AI plates were prepared and tested for non-UV germicidal activity without using UV. It was tested using model microorganisms such as Bakers Yeast （Saccharomyces cerevisiae）, Bacillus subtilis, Pseudomonas putida, and Escherichia coli. On the basis of the germicidal activity of catalyst and the degree of damage caused to the cells, the stained cells may appear green （viable）, green with red or yellow nuclei and yellow （compromised） or red （nonviable）. According to their stained color, cells were counted to calculate the percentage of dead, live, and compromised cells. Compromised cells are cells that grow very slowly after reculturing indicating a degree of reversible cell damage. Screening the germicidal activity using this staining method is accurate and efficient, and requires less time than the culture-based method. A modification to the procedure for measuring germicidal activity of rough surfaces or fibrous coatings was developed. Both TiO2 and metal-doped TiO2 （Ag, Pt, Au, Cu） possess non-UV based germicidal activity. The germicidal activity of TiO2 was found to be related with its wetting property and can be improved by UV irradiation before testing. It is not greatly affected by contact time, indicating a fast acting germicidal activity.     

Simulated single-bicycle crashes in the VTI crash safety laboratory

Abstract

Objective: The objective of this study was to examine the influence of bicycle design and speed on the head impact when suffering from a single-bicycle crash, and the possibility to study this using crash tests.

Methods: Simulations of single-bicycle crashes were performed in the VTI crash safety laboratory. Two bicycle crash scenarios were simulated: “a sudden stop” and “sideways dislocation of the front wheel”; using four different bicycle types: a “lady’s bicycle”, a commuter bicycle, a recumbent bicycle and a pedelec; at two speeds: 15 and 25?km/h. In addition, sideway falls were performed with the bicycles standing still. All tests were done with a Hybrid II 50^th percentile crash test dummy placed in the saddle of the bicycles, with acceleration measurements in the head.

Results: The crash tests showed that a sudden stop, e.g. a stick or bag in the front wheel, will result in a falling motion over the handle bars causing a forceful head impact while a sideways dislocation of the front wheel will result in a falling motion to the side causing a more moderate head impact. The falling motion varies between the different bicycle types depending on crash test scenario and speed. The pedelec had a clearly different falling motion from the other bicycle types, especially at a sudden stop.

Conclusions: The study implies that it is possible to examine single-bicycle crashes using crash tests, even though the setup is sensitive to minor input differences and the random variation in the resulting head impact values can be large. Sideway falls with the bicycles standing still were easier to perform with a good repeatability and indicated an influence of seating height on the head impact.