A prototype printer for laser driven micro-transfer printing

This paper demonstrates a new mode of automated micro transfer printing called laser micro transfer printing (LμTP). As a process, micro-transfer printing provides a unique and critical manufacturing route to extracting active microstructures from growth substrates and deterministically assembling them into a variety of functional substrates ranging from polymers to glasses and ceramics and to metallic foils to support applications such as flexible, large-area electronics, concentrating photovoltaics and displays. Laser transfer printing extends micro-transfer printing technology by providing a non-contact approach that is insensitive to the preparation and properties of the receiving substrate. It does so by exploiting the difference in the thermo-mechanical responses of the microstructure and transfer printing stamp materials to drive the release of the microstructure or ‘ink’ from the stamp and its transfer to substrate. This paper describes the process and the physical phenomena that drive it. It focuses on the use of this knowledge to design and test a print head for the process. The print head is used to demonstrate the new printing capabilities that LμTP enables.     

纤维球过滤的适应性和稳定性的研究

论述了纤维球过滤技术用于给水处理和废水处理的效果和适应情况，并和砂滤进行了同步比较试验．同时，探讨了纤维球滤料的反冲洗条件和反冲效果，并经长期运行以观察纤维球过滤的稳定性．     

基于混合遗传算法的模拟电路自动设计研究

模拟电路在电子系统设计中具有重要意义．模拟电路设计包括电路拓扑结构设计和元件值设计,这两个方面对计算机辅助模拟电路设计都很重要．但是,传统的遗传算法在不断进化电路元件值时效率低．因此,本文提出一种具有超突变和精英策略的混合遗传算法HME-GA．该方法不仅可以用来设计电路的拓扑结构,而且可用于设计电路的元件值．实验结果表明,HEM-GA算法优于简单遗传算法GA,可作为计算机辅助模拟电路设计的有效方法,在模拟电路自动化设计中具有非常重要的意义和巨大的应用潜力．     

生化-混凝沉淀-砂滤工艺处理毛巾印染废水

根据毛巾印染废水水质特点 ,选择了厌氧折流板反应池 -生物接触氧化池 -混凝沉淀 -砂滤处理工艺。运行结果表明 ,在进水水质为 :CODCr5 89～ 2 980 mg/L、BOD5 2 49～ 5 3 4 mg/L、SS12 3～ 190 mg/L、色度 3 0 0～80 0倍、p H8.76～ 9.5 6时 ,出水水质达到《纺织染整工业水污染物排放标准》( GB42 87— 92 )一级标准。该处理系统耐冲击负荷 ,运行稳定、简单 ,基建和运行费用较低。     

印染废水处理工艺的改造实践

由于原有的废水处理系统的处理效果不能达到应有的处理目标。废水的色度、COD_(cr)、BOD_5、硫化物仍然经常出现超标现象。所以必须对原有的废水处理系统进行改进。通过实验室小试,确定新的絮凝剂和最佳操作条件,同时对接触氧化池的填料更换,提高废水中污染物的去除效率,使出水水质达到行业排放一级标准。该工艺具有运行费用低、处理效果稳定等特点,尤其适合中小型印染厂废水治理。     

The effect of ink types and printing processes on flotation deinking efficiency of wastepaper recycling

Wastepaper is the largest fraction of solid waste. Flotation deinking plays an essential role in the product quality and process cost of wastepaper recycling. This paper investigated the effect of ink types and printing processes on flotation deinking. Examination of ink types in this study revealed that newsprint oil-based offset-cold and offset-heat inks contain substantial oil (45 to 60%) and resin (5 to 35%); water-based ink contains water (40%) and resin (polystyrene, 30%); and these inks are liquids with densities around 1 g/cm³ at 25 °C. On the other hand, photocopy and laser-print toners were found to be solid powders with particle diameters of about 20 μm, densities of 1 to 1.5 g/cm³, and a composition that consists primarily of styrene-acrylate copolymers (60 to 90%). Except for water-based ink, which is water soluble, all inks in their initial state are hydrophobic. It was found that for newsprint oil based offset-cold inks there is little change in their surface chemical properties, and their hydrophobic character is retained. These inks in the newsprint wastepaper pulp can be effectively removed by flotation. On the other hand, it was found that during the printing processes, the toner particles undergo polymerization (fusion) and oxidation with the subsequent formation of peroxide bonds due to exposure to heat, light, and oxygen (air). The fusion due to polymerization causes bonding to the paper fibers and the creation of larger toner particle sizes. The oxidation creates a greater polarity at the toner particle surface. These effects account for the poor efficiency in the flotation deinking of office waste. In order to improve office wastepaper recycling, it is evident, based on this study and policy considerations, that there is a need to find ways of improving the efficiency and effectiveness of flotation deinking by modification of the surface properties of printed toner particles, or designing new toner particles.     

水解酸化/生物膜法SBR处理印染废水实验研究

针对印染废水污染物浓度高、种类多、色度高、可生化降解性差等特点,对印染废水采用水解酸化/生物膜法SBR进行处理,结果表明,该处理工艺处理效果较好,出水COD、色度、BOD5、NH3-N浓度分别为60~100 mg/L、50~70倍、20~24 mg/L、5~10 mg/L,平均去除率分别达到92.1%、86.5%、95%、90%。     

高速铁路客运车站气力垃圾收集输送系统应用研究

近年来国内高速铁路发展迅猛,同时也新建了一些高速铁路车站,但目前国内铁路车站站车垃圾仍然采用原始的人工收集或者人工机械混合收集的方式,这些传统的垃圾收集方式影响城市形象及人身健康。气力垃圾收集输送系统是目前国际最为先进的垃圾收集输送系统,文章对该系统在高速铁路车站的应用进行了研究,提出了具体的实施方案。     

印染废水处理工艺改造的实践与探讨

根据某印染废水的特点 ,在原有传统处理工艺的基础上进行了工艺改造 ,将调节池改为水解酸化池 ,将活性污泥曝气池改为接触氧化池 ,在池内形成了合理的微生物分布 ,大大地改善了出水水质 ,使 COD、SS、硫化物、色度的去除率分别提高了 2 2 %、10 %、36 .4%、2 5 %。既满足废水排放标准 ,又节约了土建资金。     

全自动烷基汞分析仪测定水中烷基汞的方法研究

建立了全自动烷基汞分析仪测定水中的烷基汞(甲基汞,乙基汞)的方法.实验中衍生化反应所用的试剂为含有2.0 mol/L醋酸缓冲液,1%(g/v)NaBEt4(四乙基硼化钠)和1%(g/v)NaBPr4(四丙基硼化钠)的2%(g/v)氢氧化钾-水溶液,经衍生化的水样直接吹扫捕集后,进入气相色谱柱中分离并高温裂解,最后进入冷原子荧光检测器(CVAFS)中检测甲基汞和乙基汞的含量.甲基汞和乙基汞的方法检出限分别为0.002 ng/L和0.005 ng/L.     

安徽省水质自动监测站点位优化方法研究

文章分析了安徽省现有水质自动监测站布设情况和国内外相关研究情况,指出了现有水质自动监测站建设的不足之处,明确了水环境质量预警和水质断面目标考核两个优化布设目标。就水质自动监测站点位优化的筛选方法进行研究与讨论,提出“理论筛选一现场调研一综合打分”三步走策略,在此基础上提出了水质自动监测站布点三级指标体系。并采用德尔斐法确定权重,建立了合理性综合指数评价体系细则,为环境管理提供了参考。     

A review of process development steps for new material systems in three dimensional printing (3DP)

Three dimensional printing (3DP) is a method for direct digital manufacturing that provides capabilities for creating a wide range of part geometries (including internal channels) in a broad variety of materials, including just about anything that is available as a spreadable powder. Taking advantage of the full variety of materials requires development of specific implementations of 3DP. This paper organizes the process of 3DP implementation into five steps (powder formulation, binder method selection, binder formulation and testing, printing process specification, and post-processing specification) and presents a review of the literature relevant to each step in 3DP implementation.     

PM_(2.5)手工法与自动法比对差异及其与气象条件影响关系分析

通过在杭州、衢州和温州三个城市开展PM2.5手工法和自动法比对试验,分析PM2.5手工法和自动法的比对差异及其与气象条件的影响关系,以期为PM2.5自动监测的现场手工比对工作积累一定的经验,确保PM2.5自动监测数据的准确性。     

Reuse of printing and dyeing wastewater in processess assessed by pilot-scale test using combined biological process and sub-filter technology

In this work, a pilot-scale (300 m³/d) wastewater reclamation system was tested for printing and dyeing wastewater treatment from a textile factory. The wastewater was first hydrolyzed under anoxic condition, and then was treated under aerobic condition. Biologically treated wastewater was filtered by sub-filter technology (Patent: CN1308024A). The results showed that the average concentration of CODcr, color and turbidity in the effluent were less than 50 mg/L, 10 times and 2 NTU, respectively. The average CODcr, color and turbidity removal efficiencies were 91%, 92.5% and 90.9%, respectively. The treated effluent quality satisfied the requirement of water quality for printing and dyeing process. The most attracting part of the work was its extremely low color, low turbidity, low concentration of Fe and Mn, which was always demanded in textile sectors for an improved finish and better quality dyeing.     

中试规模ABR反应器提高印染废水的可生化性

采用厌氧折流式反应器（ABR）处理印染废水。结果表明,在其他条件不做人为改变的前提下,保证PH为9左右,温度处于25℃时,水力停留时间（HRT）会明显影响出水的BOD5／CODcr（以下简写为B／C）。在HRT为10h,8．5h,12h,1411,16h,15h出水B／C均值为O．23,O．21,O．25,0．28,0．27,0．30。在HR．T为15h,出水的BOD5／CODcr值明显提高,实现了可生化性的有效改善。从运行管理的经济性和提高出水的可生化性考虑,处理印染废水的HRT选择15h为佳．     

中试规模ABR反应器提高印染废水的可生化性

采用厌氧折流式反应器（ABR）处理印染废水.结果表明,在其他条件不做人为改变的前提下,保证PH为9左右,温度处于25℃时,水力停留时间（HRT）会明显影响出水的BOD5/CODcr（以下简写为B/C）.在HRT为10h,8.5h,12h,14h,16h,15h出水B/C均值为0.23,0.21,0.25,0.28,0.27,0.30.在HRT为15h,出水的BOD5/CODcr值明显提高,实现了可生化性的有效改善.从运行管理的经济性和提高出水的可生化性考虑,处理印染废水的HRT选择15 h为佳.     

螺旋管-高效液相色谱法在线检测甲醛的研究

研究建立了一种大气环境中气态甲醛在线采样分析系统。该系统通过螺旋管液相吸收和高效液相色谱衍生法,实现了对大气气态甲醛的在线分析。大气中的气态甲醛经过在螺旋管内经液相吸收后,与2,4-二硝基苯肼(DNPH)吸收液在加热条件下充分反应,衍生产物通过高效液相色谱(HPLC)分离后进入紫外检测器(UV)进行检测。采样和分析系统通过DasyLab实现自动运行。该方法可实现在线连续检测,时间分辨率为60min,气态甲醛的检测限可达0.10μg/L。将该方法与乙酰丙酮分光光度法(GB/T15516-1995)进行比对实验,两种方法的检测结果线性相关系数R2=0.9815。采用该方法于2007年10月在北京市进行实际采样分析,得到甲醛浓度平均浓度为4.82μg/L,并呈现明显的日变化,夜间最低,中午及午后较高。     

Living with nuclear energy

Whether we like it or not we are part of the nuclear age, and we are compelled to live with nuclear energy; with the possible exception of hydroelectric power the nuclear option is, on the record to date, the cheapest, the safest and the least environmentally harmful of any existing source of electricity generation.