金属掺杂对TiO2光催化还原CO2制甲酸甲酯活性的影响

采用溶胶-凝胶法制备掺杂金属改性的TiO2光催化剂,并研究其光催化还原CO2制甲酸甲酯的反应效果。以钛酸丁酯为主要原料,制备纳米TiO2。通过改变金属掺杂量、焙烧温度、前躯体pH等,确定出适宜的催化剂制备条件。结合SEM、XRD、UV-vis等对催化剂进行了形貌、结构和吸光行为的表征。进而考察了其光催化还原CO2的活性。结果表明:溶胶-凝胶法制备掺杂金属的TiO2,可使金属均匀地分布于TiO2表面,经催化活性评价,获得适宜的掺杂元素和掺杂量,优选的制备条件为溶胶pH=2.5～3、凝胶焙烧温度500℃,在催化剂用量1mg/mL,光照强度2880μw/cm2的反应条件下,可有效地促进TiO2光催化还原CO2制甲酸甲酯。     

核壳型TiO2／HAP纳米复合光催化剂的制备与表征

采用非均相沉淀的方法，首次在纳米TiO2的表面诱导沉积一层羟基磷灰石（HAP）。通过X射线衍射（XRD）和傅立叶红外光谱（FT-IR）对制备的样品进行结构和成分分析；用原子力显微镜（AFM）、扫描电子显微镜（SEM）和电子能谱仪（EDS）对样品包覆进行表征；采用甲基橙的光催化降解反应和大肠杆菌吸附率测定对所制光催化剂的光催化活性和吸附特性进行了评价；并与纯的纳米TiO2进行比较分析，文中还初步探讨了TiO2／HAP纳米复合材料的包覆机理．结果表明，TiO2／HAP为核壳结构，且包覆均匀，羟基磷灰石包覆层的厚度为8nm。所制备的样品具有良好的光催化活性和对细菌良好的吸附性能。这种核壳型TiO2／HAP纳米复合材料可用作环境净化和杀菌材料．     

复合模板剂下制得介孔TiO2光催化活性的研究

以吐温-80（Tween-80）和司班-80（Span-80）为复合模板剂，采用溶胶-凝胶（sol-gel）工艺制得介孔TiO2。通过对甲基橙溶液进行光催化降解试验表明：模板剂的种类与用量、光照距离和甲基橙溶液的原始浓度等因素对所制得介孔TiO2试样的光催化活性产生明显的影响。实验结果证明，本研究所得介孔TiO2材料具有较高的光催化活性，500℃下煅烧5h制备的样品在2．5h内可使浓度为0．02g／L的甲基橙溶液降解率达到94．7％，明显高于市售纳米TiO2粉体的降解率78．1％；通过X-ray衍射分析获知所制TiO2为锐钛矿型。     

纳米TiO2的制备、醋酸改性及催化性能研究

在硬脂酸介质中，450－900℃温度下，得到不同结构的纳米TiO2；将纳米TiO2进行醋酸处理。用X射线衍射（XRD）和透射电子显微镜（TEM）对纳米TiO2的微结构进行表征，发现，在相同温度下，经醋酸改性的纳米TiO2具有较好的均匀和分散性。纳米TiO2成功用于马来酸酐聚合反应，用红外（ＩＲ）和核磁共振（ＮＭＲ）研究了相关单体和聚合物的结构。此外，对醋酸改性纳米TiO2进行了光催化降解甲基橙研究。     

TiO_2纳米膜的应用及研究进展

TiO2是一种新型的无机功能材料,纳米级TiO2(特别是TiO2纳米膜)因其独特的性能,在光电转化和光催化方面有着广阔的应用前景,特别是在光催化方面,它是当前光催化材料研究的热点之一。重点介绍近年来纳米TiO2膜半导体材料的应用及其研究进展,详细介绍了国内外对TiO2半导体材料在降解、杀菌、光致氧化、还原CO2方面的应用;同时介绍金属掺杂物对TiO2半导体材料在光催化反应中的影响。     

碳掺杂TiO2纳米管列阵的制备及其光催化性能的研究

采用电化学阳极氧化法制备TiO2纳米管列阵,并在CO气氛中对TiO2纳米管样品进行焙烧.XPS研究表明,在CO中焙烧的样品产生了Ti-C峰,说明有C的掺杂.SEM及XRD衍射实验表明,随着焙烧温度的升高,C的掺杂加速了TiO2纳米管的晶型结构向金红石相的转变,管壁明显增厚.以亚甲基蓝为光催化实验降解对象,研究了C掺杂对TiO2纳米管的光催化性能的影响,发现在550℃下焙烧后的TiO2纳米管具有较好的光催化活性,C的掺杂能明显提高TiO2纳米管的光催化性能.     

蝴蝶结状TiO2纳米粒子的制备及其光催化性能研究

以四甲基氢氧化铵（TMAOH）为结构导向剂,钛酸四丁酯（Ti（OBu）4）为钛源,低温水浴处理,再经180℃下水热晶化制备纳米TiO2,采用FT-IR、XRD、TEM、UV—Vis等测试手段对其结构和形貌进行表征,并通过苯酚的光催化降解实验测试其光催化性能,结果表明,TiO2为锐钛矿相,结晶度高,所得TiO2粒子为纳米棒,界面清晰,规整度高,经紫外光照6h后,对苯酚的降解率可达62．3％,具有较高的光催化活性。     

微波辐射溶胶-凝胶法制备TiO2薄膜及其降解铬黑T的活性

通过微波辐射溶胶一凝胶法（sol-gel）法在导电玻璃（ITO）基体上制备TiO2纳米薄膜光催化剂，考察不同加热方式、微波时间、酸处理、薄膜层数等对TiO2纳米粒子及薄膜的影响。以可见光谱（UV-VIS）、X射线衍射（XRD）对TiO2薄膜进行了表征，并通过薄膜光催化降解铬黑T溶液的性能进行了研究。实验表明，ITO玻璃表面的TiO2纳米薄膜经HNO3和微波处理后，因协同效应使薄膜的光催化活性大大增强。     

溶剂热法制备TiO_2-CuO复合颗粒及其光催化性能

采用溶剂热法制备TiO2-CuO复合颗粒,表征了复合颗粒的形貌、结构并研究其模拟太阳光下光催化还原CO2生成甲醇的性能,探讨了TiO2-CuO光催化还原CO2的机理。结果表明:TiO2-CuO复合颗粒为平均粒径约为4.5μm的空心球形颗粒,硫酸铜在复合颗粒的制备过程中具有模板剂和金属源的作用。CuO质量分数为8%的TiO2-CuO复合颗粒具有较高的光催化还原效率,在异丙醇作用下,甲醇产量达127.8μmol/g;CuO复合及异丙醇的添加能够促进电子和空穴的分离,提高光催化还原CO2效率。     

W掺杂纳米TiO2的制备及光催化性能

本文以钛酸丁酯Ti（OC4H9）4和钨酸铵（NH4）6W7O24·6H2O为原料,制备W掺杂的TiO2纳米粒子,用XRD、TEM和IR进行表征,以罗丹明B的光催化降解对其光催化性能进行了研究,表明掺杂使TiO2纳米粒子的光催化活性显著增强。     

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.……     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

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.……     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

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.     

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