扫描探针显微镜研究弛豫铁电体电畴生长

本文研究了典型弛豫铁电陶瓷0．9PMN－0．1PT中的电畴生长过程．用扫描探针显微镜的轻敲模式和抬举模式对驰豫铁电陶瓷的表面形貌和电场力像进行了观察．结果表明,在施加不同针尖电压（0．05、0．5、1V）的情况下,能够诱导材料中纳米尺度极化微区通过沿＜111＞方向180°反转,从而形成亚微米尺度电畴．     

阳极氧化法制备TiO2纳米管阵列及其光电性能研究

采用阳极氧化法在钛片上制备了TiO2纳米管阵列光电极，利用扫描电子显微镜（SEM）和X射线衍射仪（xRD）对TiO2纳米管的形貌和结构进行了表征，详细考察了氧化工艺参数对纳米管阵列形貌的影响，并通过稳态光电响应技术对TiO2纳米管电极的光电化学性能进行了研究．结果表明，在1wt％HF电解液中，控制氧化电压为20V，反应30min后，在Ti表面获得了垂直导向的TiO2纳米管阵列，孔径约为90nm，管壁厚度约为10nm．经600℃退火处理后，TiO2纳米管阵列为锐钛矿型与金红石型的混晶结构，此时电极的光电性能最佳，与TiO2纳米多孔膜电极相比，光电性能大幅提高．     

光 光度学 坎德拉

人类的生存不仅借改于太阳、月亮、星星等自然光源，还要借助于火焰吨灯等人造光源。古代中国通人氏发明的钻木取火，以及后来出现的油灯、蜡烛等都是火焰光源。美国人爱迪生（T．A．Mdison）发明的白炽灯，以及后来出现的荧光灯（日光灯）、半导体灯、高压汞灯等都是电光源。人们对于光以及这些人造光源的明亮程度的认识，经历了一段漫长的过程。光是什么？光通常是指能引起人眼的感觉（视觉）的电磁辐射或电磁波，其波长范围从红光的780nm到紫光的380nm，包括红、橙、黄、绿、青、蓝、紫各种颜色（光谱）的可见光。广义地说，从780nm以…     

溶胶-凝胶和碳热还原法制备塔状SiC纳米棒

以正硅酸乙酯（TEOS）、聚乙烯基吡咯酮（PVP）为反应前驱体，Fe（NO3）3为催化剂，采用溶胶-凝胶和碳热还原法制得了碳化硅纳米棒。运用XRD、^29Si MAS NMR、TEM和SAED等手段对样品的组成和形貌进行了表征。结果表明：产物的形貌为塔状纳米棒，且晶体沿平行于[111]的方向生长；塔形SiC棒的塔底宽约80nm。100nm，塔层厚度10nm左右，长约0．4μm-1．0μm。在催化剂Fe的作用下，过饱和CO气氛中的动力学控制过程导致了塔状SiC纳米棒的形成。     

铟锡氧（ITO）纳米晶的可控合成

本文研究了ITO纳米晶合成中不同羧酸对产物的形貌的影响。采用简便的“一锅法”,在反应体系中采用直链的正辛酸盐或具有支链结构的2一乙基己酸盐,可以分别得到单分散性较好的球状纳米晶（7．6nm±1．9nm）和纳米花（18．3±2．1nm）。我们认为这是由于反应前驱体具有不同的反应活性,并通过红外实验对这一想法进行了验证。我...     

红外LED辐射照度量值溯源方法研究

红外波段的划分在不同应用领域有多种说法．通常,红外辐射可分为3个波段：IR-A（780nm～1400nm）,IR-B（1400nm--3000nm）。IR-C（3000nm-qmm）。其中IR-A由于其能量较大,穿透深度大,对人体尤其是皮肤及眼睛的影响较大,甚至会引起白内障以及皮肤灼伤。     

活性模板法制备纳米铜粉体

采用活性模板法制备了高纯纳米铜（Cu）粉体。研究了超声波频率、焙烧温度对纳米粉体性能的影响，通过X射线衍射（XRD）、透射电子显微镜（TEM）和激光粒度分析仪等手段对样品的成分、形貌、粒度及其分布进行了分析。结果表明，模板介质炭黑具有微反应器作用、空间位阻效应和较强的还原性，模板法制得的纳米Cu粉呈规则的链状球形，无明显团聚体，平均粒径为32．3nm，粒径分布窄，粒径范围在19．4～49．5nm。     

用IBAD方法合成ZrN/W纳米多层膜

本文利用高真空离子束辅助沉积系统（IBAD）在室温下制备具有纳米尺寸的ZrN／W多层膜，通过改变双靶的沉积时间，合成一系列的具有不同调制周期（3nm～10nm）的纳米多层膜。利用AES，XRD和纳米力学测试系统，表面形貌仪表征了薄膜的成分、结构和机械性能，分析了不同调制周期对薄膜结构与机械性能的影响。结果表明：多层膜的机械性能普遍优于两种个体材料的混合相；在调制周期为8．6nm时，显示出强的ZrN（111），W（110）织构和较弱的ZrN（220）峰，与其他条件下制备的样品比较，它具有较高的硬度（～26GPa），较高的弹性模量（-310GPa）和较强的膜基结合力（～80mN）。低角度XRD分析证明了薄膜的多层结构。     

多组分掺杂单层结构有机光导体研究

研究以联苯醌衍生物作为电子传输材料（ETM）与空穴传输材料（HTM）、电荷产生材料（CGM）和成膜树脂进行匹配，制备了三组分掺杂和双组分掺杂的单层结构有机光导体，系统地研究了电荷传输材料对单层结构有机光导体静电照相性能的影响。研究结果表明，光导体的的半衰曝光量对电子传榆材料的掺杂浓度具有强烈的依赖性，半衰曝光量首先随ETM浓度的增大而减小，在780nm处，三组分掺杂光导体最低半衰曝光量为2．2μJ／cm（正充电），负充电半衰曝光量为2．8μJ／cm（负充电）：双组分掺杂正充电光导体的半衰曝光量为0．59μJ/cm^2，负充电光导体的半衰曝光量为9．6μJ／cm^2。     

应用100％相消干扰波长的双波长信号系数光度法同时测定镁和钙

在pH10．5的NH3-NH4Cl缓冲溶液中，镁和钙均能与酸性铬蓝K（ACBK）形成暗红色配合物。应用试剂ACBK褪色对钙配合物生色产生100％相消干扰的波长542nm作为镁的测定波长以消除钙的干扰，建立了测定镁的双波长信号系数光度法。于λ^aP542nm，λ^aN602nm测得镁的信号系数，为3．776，信号摩尔吸光系数1．73×10^4L·mol^-1·cm^-1，线性范围为0．02—1．80mg·L^-1。以试剂ACBK褪色对镁配合物生色产生100％相消干扰的波长553nm作为钙的测定波长以消除镁的干扰，建立了测定钙的双波长信号系数光度法，于λ^aP498nm，λ^aN553nm测得钙的信号系数fz为2．083，信号摩尔吸光系数为1．31×10^4L·mol^-1·cm^-1，线性范围为0．03～3．00mg·L^-1，为测验方法，测定了水样中的镁和钙，回收率为96％～104％。     

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.     

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.……     

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.     

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.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.