液体流量计在线检测装置的研究

文章研究开发了一套液体流量计在线检测装置,很大程度上解决了许多液体流量计（特别是大口径液体流量计）的在线检测问题。该装置采用超声波流量计作为标准表,针对其硬件接口进行软件编程,实现了检测数据自动采集、证书记录自动打印、联网信息查询等功能。     

Preferential orientation of NV defects in CVD diamond films grown on (113)-oriented substrates

Thick CVD diamond layers were successfully grown on (113)-oriented substrates. They exhibited smooth surface morphologies and a crystalline quality comparable to (100) electronic grade material, and much better than (111)-grown layers. High growth rates (15–50 μm/h) were obtained while nitrogen doping could be achieved in a fairly wide range without seriously imparting crystalline quality. Electron spin resonance measurements were carried out to determine NV centers orientation and concluded that one specific orientation has an occurrence probability of 73% when (100)-grown layers show an equal distribution in the 4 possible directions. A spin coherence time of around 270 μs was measured which is equivalent to that reported for material with similar isotopic purity. Although a higher degree of preferential orientation was achieved with (111)-grown layers (almost 100%), the ease of growth and post-processing of the (113) orientation make it a potentially useful material for magnetometry or other quantum mechanical applications.     

On modulating the Physarum polycephalum plasmodium's electrical resistance,resting membrane potential and capacitance by application of nanoparticles and nanostructures

Physarum polycephalum is a model organism used in the creation of hybrid artificial-biological devices. Among its demonstrated uses in biocomputing it is able to grow self healing ‘wires’ which can be used to generate circuitry, especially following hybridisation with nano- and micro-scale circuit components. In this study P. polycephalum plasmodia were hybridised with nanomaterials; graphene oxide, carbon nanotubes, calcium phosphate and aluminium oxide. Observations were made on toxicological effects and alterations in electrical properties; mean potential, period, frequency, resistance and capacitance. Macroscopically, there was little evidence of toxic effects on P. polycephalum using any of these nanomaterials. Capacitance was increased substantially and electrical resistance decreased in carbon nanotube-treated plasmodia, with all results for other nanomaterials being lesser in magnitude. Our results demonstrate that carbon nanotubes are a suitable material for biohybridisation in the creation of conductive cellular pathways, whilst influencing their capacitance.     

Corrosion resistance of zinc-coated structured sheet metals

The purpose of this study is to characterise the corrosion behaviour of zinc-coated sheet metals after a structuring process using the salt spray test. The investigated structured material is manufactured by hydroforming and has a periodic hexagonal geometry. The corrosion behaviour has been evaluated by estimating the development of the corrosion area and penetration depth. The results of the investigation show that the corrosion area is larger on the smooth sheet than on the structured sheet. The difference between the structured and smooth sheets is negligible with increasing exposure time. Furthermore, the reasons for the different corrosion behaviours are discussed.     

纳米材料在农药残留检测的应用研究进展

食品中的农药残留对人类健康存在潜在风险。纳米材料的快速发展为食品安全检测技术提供了前所未有的机遇。文中综述了当前主要的几种纳米材料的特点及其在食品安全领域中农药检测的应用现状,探讨了纳米粒子在食品安全领域未来的挑战和发展方向。     

基于LED的光栅光调制器照明系统的优化设计与实现

设计了一种基于LED照明的光栅光调制器(GLM)照明系统,以自由曲面TIR透镜、光棒、聚光透镜组为主要光学元件来提高LED光能利用率,并实现光场均匀化。通过仿真得出,照明系统的光能利用率为78.7%,光照均匀性为85%,实验与设计结果基本一致。这表明,优化后的光栅光调制器的照明系统,解决了基于LED的照明系统光照不均匀和光能利用率低的问题。     

Be/HR-1不锈钢热静压高温形变的组织结构

利用光学金相显微镜、扫描电镜(SEM)、X射线衍射(XRD)仪和材料试验机分析Be/HR-1和Be/Cu/HR-1不锈钢真空热静压接头扩散区高温形变的组织结构和性能,探讨形变组织结构与压力和性能的关系.研究表明:热静压的作用使试样产生扩散性蠕变和晶界滑动,影响扩散焊区的晶粒大小和金属间化合物的数量;热静压应不得在使基体晶粒最大的临界压力或临界应变量下进行,适当降低压力和缩短时间可减少沿晶生成金属间化合物的数量,提高连接接头质量;Be/Cu/HR-1不锈钢热静压反应扩散生成的新相熔点大大低于原基材,适当降低温度或压力可有效控制连接工件的变形.     

Precise positioning of piezo-actuated stages using hysteresis-observer based control

The piezo-actuated stages are composed of the piezoelectric actuator and the positioning mechanism. The positioning accuracy of the piezo-actuated stage is limited due to hysteretic nonlinearity of the PEA and friction behaviour of the positioning mechanism. To compensate this nonlinearity of piezoelectric actuator, a PI feedback control associated with feedforward compensating based on the hysteresis observer is proposed in this paper. To verify the consistency of the proposed method, the experiments are implemented by real-time control to be compared with the numerical simulation.     

LA-ICP-MS法测定高含量银饰品中的杂质元素

本文建立了一种使用激光剥蚀-电感耦合等离子质谱法(LA-ICP-MS)对高含量银饰品中22种杂质元素测定的检测方法,实现了对高纯银饰品的准确、高效、绿色环保的近无损测试。通过对Mg、Al、Ti、Cr和Mn等5个目标元素的测试,计算出当激光剥蚀系统能量密度为12.5 J/cm²、剥蚀孔径为90 μm、脉冲频率为10 Hz时为最优参数,目标元素的信号强度和稳定性达到最优。使用系列银标准样品建立工作曲线,对待测高含量银饰品进行测试。该方法的检出限为0.001~0.827 μg/g,各杂质元素的精密度在3%~25%之间,测试结果与ICP-AES的数据相吻合。     

童鞋召回中质量与限量标准情况分析

儿童皮鞋涉及儿童健康安全,目前我国童鞋参照执行的标准并未完全解决童鞋的安全问题,还存在相当一部分的安全监管空白,存在较高质量安全风险隐患。本文根据近年来出口儿童皮鞋产品的召回情况,分析儿童皮鞋产品中限量标准及相关技术法规。