扫描电子显微镜在光伏原辅材料检验中的应用

采用扫描电子显微镜对镀膜玻璃、硅片、焊带、背板等光伏原辅材料进行测试及分析,分别介绍了扫描电子显微镜在镀膜玻璃膜层结构观察、膜厚测量、硅片表面形貌及间距分析、焊带表面微观分析、背板类型分辨、各层厚度测量等方面的应用,其结果可为镀膜玻璃的性能研究、电池片工艺优化分析、焊带性能评估、背板验货及鉴定等光伏原辅材料的研究及测试提供依据。     

水泥-粉煤灰体系早龄期液相离子浓度与电导率的关系

通过离心和高压萃取法分别提取水泥-粉煤灰体系1h内和5~24h的液相,采用电感耦合等离子体发射光谱仪(ICPOES)、pH计和电导率测试仪分别测试液相离子浓度、pH值和电导率,并探究了粉煤灰掺量对体系液相离子浓度、pH值和电导率的影响。结果表明:随水化时间延长,水泥-粉煤灰体系早龄期液相中K~+浓度先降低后上升,Na~+、SiO_4~(4-)浓度和pH值逐渐上升,5h左右Ca~(2+)和SO_4~(2-)浓度达到峰值,10h左右AlO_2~-浓度达到峰值;随粉煤灰掺量增加,液相中各离子浓度和电导率呈降低趋势,根据液相电导率变化规律将体系早龄期水化进程分为溶解期、诱导期和加速期三个阶段;液相电导率与离子总浓度成正相关,主要受K~+、Na~+和OH~-浓度影响,高掺量(50%)粉煤灰对单一离子与电导率之间相关性的影响较为显著。     

电解法研究DF988膜对钠离子的水传递数

离子膜电解过程中,水分子伴随阳离子通过离子膜而发生移动的现象称为水的电渗透或水传递.简要介绍了国产DF988离子交换膜的结构.通过傅立叶红外光谱(ATR-FTIR)对DF988膜表面进行分析,表明其一侧为磺酸层另一侧为羧酸层即阻挡层.采用自制的电解测试装置对DF988膜的水传递进行了较为系统的实验研究,测定了不同条件下的水传递数和氢氧化钠中氯化钠含量,包括阳极液浓度、阴极液浓度、电流密度和温度等条件.结果表明,电解液浓度对水传递数有明显的影响,水传递数随盐水浓度的降低有明显的增大;而电流密度和温度等则对氢氧化钠中含氯化钠的量影响明显.     

焊带与晶硅太阳能电池片破碎关系

太阳能用电池片在焊接过程中会出现破碎。不论是手焊还是机焊,在焊接过程中碎片总是不可避免,因此焊接碎片率已经成为考核生产车间的一个重要指标,也成为影响晶硅光伏组件成本的重要因素。影响焊接碎片的因索有很多,本文主要从焊带与电池片的作用力方面加以考虑,研究了焊带对晶硅太阳能电池片破碎的影响。     

有机包覆改性SiC粉体表面结构与性质的表征

本研究中的有机包覆改性SiC微粉通过硅烷偶联剂处理以及有机单体在其表面上的接枝聚合而获得。通过X-射线衍射分析改性前后粉体的主要物相成分;以粉体悬浮液离心清液的离子电导率和粉体胶粒的Zeta电位曲线来表征粉体表面的吸附离子浓度及表面电性;通过TEM、FTIR等测试手段表征粉体有机包覆层的形貌和化学组成结构。研究表明:以提高SiC粉体水基分散固含量为目的的有机包覆改性工艺在未改变粉体基本成分的基础上,有效降低了粉体表面吸附离子的浓度,提高了表面电荷;其完整的表面有机包覆层体现包覆物质的结构和性质,有效地掩蔽了SiC粉体原有的表面,使有机包覆改性成为SiC粉体水基分散性能提高的有效方法。     

Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)混合导体导电性能的研究

用直流四电极法测量了空气和氮气气氛下Ba0.5Sr0.5Co0.8Fe0.2O3-δ(BSCF)的总电导率,用电子阻塞电极法测量了空气气氛下BSCF的氧离子电导率。结果表明575℃之前,BSCF呈现p型半导体的导电特征,总电导率温度升高而增大,随氧分压降低而减小;但在575～650℃总电导率显著下降,这与BSCF材料中晶格氧的逸出有关。通过电子阻塞电极法测得的BSCF氧离子电导率σi和温度T的关系符合Arrhe-nius公式,氧离子电导活化能Ea=140.7kJ/mol。通过透氧实验,由Wagner方程计算出来的氧离子电导率与电子阻塞电极法测量得到的值在700℃以下吻合;但700℃后,由于高氧端的气体与膜表面晶格氧的交换以及低氧端表面晶格氧与气相氧交换成为控速环节,使计算出来的氧离子电导率明显低于测量得到的值,并且二者差别随温度升高越来越大。     

未焊透缺陷深度对LY12铝合金搅拌摩擦焊焊缝电导率的影响

采用涡流电导测量仪,测量了LY12铝合金搅拌摩擦焊垂直于焊缝方向的电导率分布及具有不同深度未焊透缺陷处焊缝的电导率。结果表明,焊缝中部电导率较高,母材电导率较低,存在一过渡区,各区的电导率变化与其组织变化有关。未焊透深度对焊缝电导率分布曲线有影响。当未焊透深度较小时,其焊缝中心电导率相对无缺陷时变化不大。当未焊透深度较大时,其焊缝中心电导率值急剧下降,且未焊透深度越大,电导率值越低。     

丙烯酰胺三元反相微乳液体系的制备及其聚合研究

用电导法考察了不同HLB值时的电导率变化规律,研究了正丁醇、氯化钠和醋酸钠的加入对微乳液体系电导率的影响,制备了稳定的丙烯酰胺三元反相微乳液体系,并优化了该体系的聚合工艺,测定了乳液中聚合物的固含量和相对分子质量M.结果表明:HLB值为7.5时体系的电导率σ变化较小,加入5.0%(wt)的氯化钠或加入10%(wt)的醋酸钠可以增加体系的溶水量.聚合试验结果表明,通过连续测定丙烯酰胺三元反相微乳液体系σ的变化来寻求聚合工艺配比参数是可行的,该方法具有一定的实用性.     

附件角焊缝趾部裂纹对37SiMnCrMoV钢断裂强度的影响(宽板试验研究)

对位于应力集中区并且可能受到焊接角变形引起的附加弯矩作用的有限长度的焊趾裂纹来说,裂纹部分前沿总处于高应力区,其最大应力强度因子不在裂纹底部而在裂纹表面附近。裂纹底部处于平面应变状态而裂纹的表面前沿处于平面应力状态。焊趾裂纹对超高强度钢的静载强度的影响是否大于相同尺寸的平板表面裂纹是一个问题。本文对37SiMnCrMoV超高强度钢进行了宽板拉伸试验。试件上加焊各种不同刚度的附件,并在附件角焊缝趾部开人工裂纹,裂纹的深度有0.2板厚和0.4板厚两种,裂纹深长度比(a/(2c))分别为0.05和0.1。同时进行带同样尺寸裂纹的平板试验作对比。试验结果表明:对干37SiMnCr MoV钢而言附件焊趾裂纹对静载强度的影响大于平板上的表面裂纹。这种影响随着附件刚度增加而加剧。     

粗化液中钯离子对ABS塑料直接电镀的影响

粗化是实现活化液在ABS表面吸附的前提和获得良好结合力的必要条件.采用含痕量钯离子的铬酐-硫酸粗化液对ABS塑料表面进行化学粗化,用AFM、XPS和胶体钯吸附量等对粗化前后塑料的表面性能、价键状态和活性进行了考察.结果表明:钯离子加入到粗化液中对ABS表面的粗糙度影响不显著,粗化后的表面氧含量升高;随着粗化液中钯离子浓度的增加,胶体钯在ABS表面上的吸附量增加;增加粗化液中的Pd含量可使ABS表面在低浓度胶体钯溶液中达到与高浓度钯相同的吸附量,有效地降低了胶体钯的浓度.粗化液中加入钯离子不影响基体与镀层的结合力.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.