980nm InGaAs／GaAs／AlGaAs应变量子阱激光器

报导了脊形波导ＩｎＧａＡｓ／ＧａＡｓ／ＡｌＧａＡｓ应变量子阱激光器的特性和实验结果，激光器阀值电流最低为９ｍＡ，典型值为１５ｍＡ，线性输出光功率大地１２０ｍＷ，微分量子效率典型值为６０％，５０℃，８０ｍＷ恒定功率条件下老化实验结果表明；该条件下激光器寿命超过１０００小时。     

量子点激光器及其应用研究

报道了分子束外延生长出自组装垂直耦合ＩｎＡｓ／ＧａＡｓ大功率量子点激光器材料和器件。对腔长为８００μｍ,室温下和７７Ｋ下边续激射阈值电流密度分别为２１８Ａ／Ｃｃｍ＾２和４９Ａ／ｃｍ＾２,波长为９６０ｎｍ,最大输出功率大于１Ｗ。首次报道在０．５４Ｗ工作下,寿命超过３０００小时,功率仅下降０．４９display status０     

1.3μmInAsP/InGaAsP应变补偿量子阱激光器

采用气态源分隔束外延方法及应变补偿生长工艺生长了ＩｎＡｓＰ／ＩｎＧａＡｓＰ应变补偿多量子阱激光器材料,采用选择刻蚀和聚酰亚胺隔离工艺制成了脊波导型１．３μｍ激光器芯片并对芯片性能进行了统计测量,测量结果表明此种激光器芯片在室温下的阈值电流可小于１０ｍＡ,在２５℃至９０℃温度范围内特征温度大于９０Ｋ,并表现出较好的单纵模特性。     

连续输出20WAlGaAs／GaAs量子阱激光二极管线列阵

采用ＭＯＣＶＤ实现了ＡｌＧａＡｓ／ＧａＡｓ量子阱结构，获得了连续输出２０Ｗ激光二极管线列阵，线列阵长度１．０ｃｍ，激射波长８０８±４ｎｍ。     

940nm高功率列阵半导体激光器

利用分子束外延生长方法生长出ＩｎＧａＡｓ／ＧａＡｓ应变量子阱材料。利用该材料制作出的应变量子阱列阵半导体激光器准连续（５００μｓ,１００Ｈｚ）输出功率达到２７Ｗ（室温）,峰值波长为９３９￣９４１ｎｍ,并分析了影响列阵半导体激光器输出功率的因素。     

国产金属有机化合物TMGa,TMAl,TMIn和TMSb的MOVPE鉴定

利用我们研制的常压ＭＯＶＰＥ设备对国产ＴＭＧａ、ＴＭＡｌ、ＴＭＩｎ和ＴＭＳｂ进行了鉴定，为此分别生长了ＧａＡｓ、ＡｌＧａＡｓ、ＩｎＰ、ＧａＳｂ外延层和ＧａＡｓ／ＡｌＡｓ、ＧａＳｂ／ＩｎＧａＳｂ超晶格和ＧａＡｓ／ＡｌＧａＡｓ量子阱结构。表征材料纯度的７７Ｋ载流予迁移率分别达到ＧａＡｓ：μ＿ｎ＝５６６００ｃｍ￣２／Ｖ·ｓ，Ａｌ＿（０．２５）Ｇａ＿（０．７５）Ａｓ：μ＿ｎ＝５１６０ｃｍ￣２／Ｖ·ｓ，ＩｎＰ：μ＿ｎ＝６５３００ｃｍ￣２／Ｖ·ｓ，ＧａＳｂ：μ＿ｐ＝５０７６ｃｍ￣２／Ｖ·ｓ。由１０个周期的ＧａＡｓ／ＡｌＡｓ超晶格结构组成的可见光区布拉格反射器已观测到很好的反射光谱和双晶Ｘ射线回摆曲线上高达±２０级的卫星峰。ＧａＡｓ／Ａｌ＿（０．３５）Ｇａ＿（０．６５）Ａｓ量子阱最小阱宽为１０，在ｌｉＫ下由量子尺寸效应导致的光致发光峰能量移动为３９０ｍｅＶ，其线宽为１２ｍｅＶ。这些结果表明上述金属有机化合物已达到较高质量。     

1.52um InGaAsP／InP分别限制量子阱激光器

报导了在６００℃生长温度下以三甲基镓（ＴＭＧａ）和三甲基铟（ＴＭＩｎ）为Ⅲ族源，用低压金属有机气相沉积（ＬＰ－ＭＯＣＶＤ）技术生长出的高质量１．６０ｕｍ和１．３ｕｍ ＩｎＧａＡｓＰ材料，以及在其分别限制量子阱结构生长的情况下，用质子轰击方法制得的条形结构量子阱激光器。该激光器在室温下直流阈值电流为１００ｍＡ。     

实用化GaInP—AlGaInP半导体量子阱可见光激光器

用低压ＭＯＶＰＥ方法研制出了波长为６５５ｎｍ与６７０ｎｍ的ＧａＩｎＰ－ＡｌＧａＩｎＰ半导体量子阱可见激光器，并已形成一定的批量生产能力。器件的阈值电流典型值为４５ｍＡ，输出光功率不小于５ｍＷ，最高工作温度不低于５０℃，预计２０℃时寿命接近１００，０００小时，主要技术指标与目前进口的同类产品水平相当，完全可以满足实用要求。     

1．52μmInGaAsP／InP分别限制量子阱激光器

报导了在６００℃生长温度下以三甲基镓（ＴＭＧａ）和三甲基铟（ＴＭＩｎ）为Ⅲ族源，用低压金属有机气相沉积（ＬＰ－ＭＯＣＶＤ）技术生长出的高质量１．６０μｍ和１．３μｍＩｎＧａＡｓＰ材料，以及在其分别限制量子讲结构生长的情况下，用质子轰击方法制得的条形结构量子阱激光器。该激光器在室温下直流阈值电流为１００ｍＡ。     

实用化GaInP－AlGaInP半导体量子阱可见光激光器

用低压ＭＯＶＰＥ方法研制出了波长为６５５ｎｍ与６７０ｎｍ的ＧａＩｎＰ－ＡｌＧａＩｎＰ半导体量子阱可见光激光器，并已形成一定的批量生产能力。器件的阈值电流典型值为４５ｍＡ，输出光功率不小于５ｍＷ，最高工作温度不低于５０℃，预计２０℃时寿命接近１００，０００小时，主要技术指标与目前进口的同类产品水平相当，完全可以满足实用要求。     

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...     

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.     

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.     

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.……     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

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.     

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.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

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.