新型有机/无机复合材料的合成及其二阶非线性光学特性

以 γ-异氰酸基丙基三乙氧基硅烷 (简称 ICPTEOS)作中间体 ,用溶胶 -凝胶法 (Sol- Gel)合成了含对硝基偶氮苯酚 (NHA)生色团的新型键合型有机 /无机复合非线性光学 (NLO)材料 ,在这种有机生色团与无机玻璃键合形成的交联网络结构中 ,无机玻璃的刚性三维结构和优良的高温稳定性能有效抑制NLO生色团的极化松弛。二次谐波信号 (SHG)测量表明 :合成的键合型聚合物膜的二阶非线性光学系数 (d3 3 )值可达 2 .0 1× 10 -7esu;NL O稳定性也较好 ,在室温下放置 90 d,其 d3 3 值能维持初始值的92 .1% ;在 10 0℃放置 30 0 min,其 d3 3 值仍能维持初始值的 5 7.3%。     

新型PU-DR19-SiO2纳米复合材料的制备和表征

利用溶胶-凝胶法将硅烷染料、含硅氧烷的非线性聚氨酯与TEOS共水解-缩合首先制备了新型PU-DR19-SiO2纳米复合材料,并用IR、SEM、TEM、UV-vis和DSC-TGA对其结构和性能进行了表征.结果显示:材料中有机相与无机相以共价键相连,没有发生相分离,且其中非线性较好的DR19生色团含量和材料的Tg都较纯NLO/PU有显著增加,可以用来制备性能优良的二阶非线性光学器件.     

以噻吩并[2,3-b]噻吩为给体的生色团分子的电子光谱及二阶非线性光学性质的计算研究

本文围绕如何通过理性的分子设计、实现有机NLO生色团的"二阶非线性活性—透明性—热稳定性"的综合优化开展工作。基于噻吩较小的共振能及噻吩并噻吩较高的热稳定性,本文设计了以噻吩并[2,3-b]噻吩为给体,连接不同受体基团的推-拉型生色团,用密度泛函理论方法对它们的电子光谱和二阶非线性光学性质进行了系统的研究,为该类有机NLO材料的筛选和制备,提供理论先导。     

新型PMMA/SiO_2/DR1非线性光学杂化材料的制备及表征

通过溶胶-凝胶法将硅烷染料DR1ASD、含硅氧烷PMMA和TEOS在酸催化条件下共水解-缩合制备了新型非线性光学杂化材料PMMA/SiO2/DR1,并运用FT-IR、SEM、UV-vis、DSC/TG和UV-vis等测试方法对其结构和性能进行表征.测试结果表明:杂化材料中有机相和无机相之间通过共价键结合,无相分离出现;杂化材料的玻璃化转变温度(Tg)和热分解温度(Td)分别达到165℃和405℃;电晕极化后杂化材料具有较高的生色团取向有序度(Φ=0.238),并表现出良好的取向稳定性,80℃条件下3h后依然有初始值的79%.     

功能化甲基丙烯酸甲酯共聚物合成及其交联膜的二阶非线性光学性能

合成了一种甲基丙烯酸甲酯与侧链含有偶氮苯生色团和可化学交联基团-羟基的甲基丙烯酸酯共聚物,这种共聚物和甲苯-2,4-二异氰酸酯(TDI)交联得到的交联网络结构使极化后生色团取向稳定化.SHG测量表明,固化后的聚合物膜的非线性光学稳定性较好,其二阶非线性光学系数d33值室温下1680 h能维持初值的～96%,100 ℃时1000 min仍能维持初值的～70%.极化交联膜的d33值也较高,达到6.10×10-7 esu.     

π电子共轭键结构对材料非线性光学性能影响研究

合成了具有不同π电子共轭键3个新的有机光学材料4-(吡啶-4-乙烯),4'-(N,N-二羟乙基氨基)二乙烯苯(a),N-((4-(N,N-二羟乙基氨基)-苯亚甲基)-4-(吡啶-4-乙烯)苯胺(b)和4-(吡啶-4-乙烯),4'-(N,N-二羟乙基氨基)偶氮苯(c),使用脉宽8ns波长532nm调Q倍频ns/ps Nd:YAG脉冲激光系统测试了它们的非线性光学性能,研究了分子结构与非线性光学性能之间的关系.结果显示这些化合物具有大的三阶非线性光学系数,这可能来源于它们长的D-π-A共轭电子结构;以N=N双键为共轭键的化合物的非线性光学性能优于以C=N或G=C双键为共轭键的化合物.     

有机生色团掺杂有机／无机复合基质非线性光学材料的制备与性能

以4-[乙基-（2-羟乙基）胺]-4’-硝基偶氮苯（DRl）为生色团，甲基丙烯酸甲酯（MMA）和正硅酸乙酯frEOS）为先体，通过原位溶胶-凝胶技术制备了新型的以PMMA／SiO2复合材料为掺杂基质的二阶非线性光学杂化材料，并运用提拉法在洁净的ITO导电玻璃上制备出均匀、透明的厚度为1μm左右的杂化薄膜。DSC测得杂化材料的玻璃化转变温度为130℃；二次谐波产生（SHG）测量结果表明杂化薄膜在电晕极化后二阶非线性系数d33为1．02×10^7esu；用UV-vis光谱对杂化膜在极化前后的取向和取向稳定性进行的研究表明此材料具有较高的取向度，且常温下的取向稳定性也较好，60d后取向序参数φ仍有初始值的85％。     

一种新型二阶非线性光学聚合物材料

报导了一种新型含有五员呋喃杂环非线性光学生色团,并且引入到聚甲基丙烯酸甲酯侧链中。旋转涂膜后,采用电晕极化、紫外－可见光谱研究表明色团虽然具有较大共轭长度,其截止吸收波长却很小。同是该聚合物聚向稳定性很好。     

有机-无机杂化纳米复合材料合成及性能测试

采用溶胶-凝胶法,以甲基三乙氧基硅烷(MTEOS)和正硅酸乙酯(TEOS)及纳米氧化硅为原料,成功制备了有机-无机杂化纳米复合材料及涂层.以X射线衍射(XRD)、富立叶红外光谱(FTIR)、扫描电子显微镜(SEM)和原子力显微镜(AFM)等手段研究了杂化材料的工艺与结构及性能的关系,并对涂覆于铝合金基体上的纳米复合材料涂层的防腐蚀性能进行了实验检测.结果表明,有机-无机杂化纳米复合材料涂层具有优良的抗腐蚀性能.     

脉冲电压对硅/玻璃阳极键合质量影响分析

采用脉冲电压对硼硅玻璃与硅进行了阳极键合试验,结果表明采用脉冲电压能有效缩短硅/玻璃阳极键合时间并能适当降低键合温度。通过拉伸试验表明键合强度能达到预定强度要求,通过扫描电镜对键合界面的微观界面进行分析:表明玻璃/硅的键合界面有较明显的中间过渡层生成;通过分析:认为在玻璃/硅进行阳极键合过程中,脉冲电压产生的脉冲电场力对玻璃Na~+耗尽层中的O~(2-)向界面迁移扩散起到了反复驱动的作用,促进了O~(2-)向阴极表面迁移,增加了界面键合效率,缩短了硅/玻璃阳极键合时间,并降低了键合温度,从而促进了过渡层的形成。     

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.……     

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.     

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.     

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