快速凝固高阻尼Al—Zn—Mg—Cu系合金的研究

本文研究了利用快速凝固粉末冶金工艺制备高阻尼Ａｌ－Ｚｎ－Ｍｇ－Ｃｕ系合金。通过拉伸性能与阻尼性能的测试，以及显微组织分析，探讨了纯铝及石墨对合金拉伸性能及阻尼性能的影响。结果表明：Ａｌ－Ｚｎ－Ｍｇ－Ｃｕ／１５ｗｔ％Ａｌ合金的室温拉伸性能已达到ＬＣ９ＣＧＳ１的水平，阻尼性能为Ｑ＝６．０×１０＾－３；在室温至３００℃温度范围内，随着温度的升高，合金的阻尼能力提高；合金的阻尼机制属复合型机制。     

RS高强Al－Zn－Mg－Cu系合金热处理温度与性能的关系

本文系统研究了ＲＳ高强Ａｌ－Ｚｎ－Ｍｇ－Ｃｕ系合金淬火温度、时效温度与性能关系，同时还分析了合金的微观组织。试验得出在４７０℃淬火峰时效（Ｔ６）的拉伸性能达到σ_ｂ＝７４０ＭＰａ，σ_（０．２）＝７０２ＭＰａ，δ_５＝１０％；双级时（Ｔ７３）可获得σ_ｂ＝６３３ＭＰａ，σ_（０．２）＝６０６ＭＰａ，δ_５＝１１．５％。合金的弥散强化相是Ｃｏ_２Ｎ_９、Ａｌ_３Ｚｒ，沉淀强化相为ＧＰ区、η＇和η。     

低密阻尼金属/金属复合体材料的组织与性能研究

采用快速凝固／粉末冶金法成功地研制出Ａｌ－７．０９％Ｆｅ－１．３４％Ｍｏ－１．４５％Ｓｉ（ＦＭＳ０７１４）合金及其金属／金属复合体材料ＦＭＳ０７１４／１５％Ａｌ和ＦＭＳ０７１４／１０％（Ｚｎ－３０％Ａｌ）,考察了其组织、拉伸性能、阻尼性能和密度,产散锻铝ＬＤ７ＣＳ合金进行了对比。结果表明：ＦＭＳ０７１４合金本身就具有较好的拉伸与阻尼性能。添加纯Ａｌ和Ｚｎ－３０％Ａｌ合金粉均使其强度下降,而 ＦＭＷ     

RS高强Al－Zn－Mg－Cu系合金热处理温度与性能的关系EI

本文系统研究了ＲＳ高强Ａｌ－Ｚｎ－Ｍｇ－Ｃｕ系合金淬火温度、时效温度与性能关系，同时还分析了合金的微观组织。试验得出在４７０℃淬火峰时效（Ｔ６）的拉伸性能达到σ_ｂ＝７４０ＭＰａ，σ_（０．２）＝７０２ＭＰａ，δ_５＝１０％；双级时（Ｔ７３）可获得σ_ｂ＝６３３ＭＰａ，σ_（０．２）＝６０６ＭＰａ，δ_５＝１１．５％。合金的弥散强化相是Ｃｏ_２Ｎ_９、Ａｌ_３Ｚｒ，沉淀强化相为ＧＰ区、η＇和η。     

Cu－Zn－Al－Mn－Ni－Ti合金的显微组织及力学行为

本文利用电子拉伸试验、扫描电镜、金相显微镜研究了Ｃｕ－Ｚｎ－Ａｌ－Ｍｎ－Ｎｉ－Ｔｉ合金的细化效果、断裂方式、记忆性能及伪弹性。结果表明：试验合金的铸态、轧态和淬火态组织得到明显细化。晶粒细化后合金室温拉伸断裂强度为７５０ＭＰａ，断裂应变为６．６％，同未细化的Ｃｕ基记忆合金相比强度大大提高，塑性也有所改善。低温拉伸时呈穿晶断裂，断口主要为准解理台阶；高温拉伸时呈微孔聚集型断裂。试验合金的室温完全可恢复应变为４．０％，完全伪弹性恢复应变为４．５％，均达到了多晶体材料的理论平均值。     

Al－Li－Cu－Mg－Zr合金的晶界断裂

本文通过室温拉伸试验，利用扫描电镜和透射电镜研究了Ａｌ－Ｌｉ－Ｃｕ－Ｍｇ－Ｚｒ合金不同时效状态下的拉伸性能和断裂行为。结果表明，该合金的力学性能与主要强化相δ＇（Ａｌ３Ｌｉ）的尺寸有关，其断裂行为决定于位错的共面滑移程度和滑移与晶界沉淀相的交互作用。     

SiC_w／Al－Li－Cu－Mg－Zr复合材料压铸工艺的研究

本文利用挤压铸造法成功制备了ＳｉＣ_ｗ／Ａｌ－Ｌｉ－Ｃｕ－Ｍｇ－Ｚｒ复合材料。采用化学分析、电子探针和扫描电镜等分析测试手段对材料进行化学分析和组织观察。结果表明，所获得的复合材料样品中晶须分布均匀，各合金元素含量均可控制在成分设计范围内。拉伸试验结果表明，ＳｉＣ_ｗ／Ａｌ－Ｌｉ－Ｃｕ－Ｍｇ－Ｚｒ复合材料具有较优异的综合拉伸性能。     

惯性导航仪用新型铸造铝合金研究

研究了惯性导航仪用新型Ａｌ－Ｚｎ－Ｍｇ系高尺寸稳定性铸造铝合金。新型合金为ＺＡｌＺｎ４Ｍｇ４，具有较高强度及良好的综合性能。研究了Ｚｎ、Ｍｇ、Ｃｕ、Ｔｉ及Ｚｒ等元素和热处理工艺对合金性能的影响，并测定了合金的物理性能和尺寸稳定性。     

Cu—Zn—Al—Mn—Ni—Ti合金的显微组织及力学行为

本文利用电子拉伸试验，扫描电镜，金相显微镜研究了Ｃｕ－Ｚｎ－Ｍｎ－Ａｌ－Ｔｉ合金的细化效果，断裂方式，记忆性能及伪弹性。结果表明：试验合金的铸态，轧态和淬火态组织得到明显细化。晶粒细化后合金室温拉伸断裂强度为７５０ＭＰａ，断列应变为６．６％，同未细化的Ｃｕ基记忆合金相比强度大大提高，塑性也有所改善。低温拉伸时呈穿晶断裂，断口主要为准解理台阶；高温拉伸时呈微孔聚集型断裂。试验合金的室温完全可恢复应变     

ALCHEMI法测定有序合金的马氏体和贝氏体相的原子组态

虽然Ｃｕ－Ｚｎ－Ａｌ和Ｃｕ－Ａｕ－Ｚｎ合金中的母相已知为ＤＯ３或Ｌ２１结构，但通过通道增强微分析原子定位法（ＡＬＣＨＥＭＩ），可以检测Ｃｕ－Ｚｎ－Ａｌ合金的母相，马氏体相和Ｃｕ－Ａｕ－Ｚｎ合金的母相、马氏体、贝氏体相中的原子配置，结果表明，马氏体相中原子配置与母相是完全一样的，但Ｃｕ－Ｚｎ－Ａｌ合金听时效马氏体的Ｃｕ－Ａｕ－Ｚｎ合金中贝氏体与母相不同。本文叙述ＡＬＣＨＥＭＩ测定的结果。     

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.     

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.     

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.……     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.