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First-Principle Calculations of Hardness and melting Point of mo_2C

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Journal of materials Science & Technology 2009年第3期25卷 419-422页

作者： X.R. Wang m.F. Yan H.T. Chen School of materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

This paper has constructed two kinds of atomic and electronic models for hexagonal β-mo2C and orthorhombic α-mo2C. The optimized lattice parameters, elastic constant matrixes and overlap population for mo2C crystal cells have been obtained to realize the characterization of the hardness and melting point of the two structures by the first-principles plane wave pseudo potential method based on the density functional theory. The results reveal that the calculated lattice parameters of the mo2C crystal cells agree with the experimental and other calculated data. The calculated melting point/hardness are 2715 K/11.38 GPa for β-mo2C and 2699 K/10.57-12.67 GPa for α-mo2C, respectively. The calculated results from the density of states （dOS） demonstrate that the hybridization effect between mo-3d and C-2p states in α-mo2C crystal cell is much stronger than that in β-mo2C one.

关键词： First-principle mo2C Hardness melting point density of states

Annual performance analysis of different maximum power point tracking techniques used in photovoltaic systems

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Protection and Control of modern Power Systems 2019年第1期4卷 183-192页

作者： Y.Chaibi A.Allouhi m.Salhi A.El-jouni 2EmI team ENSAMMoulay Ismail University50500B.P 15290 El MansourMeknesMorocco Ecole Supérieure de Technologie de Fès U.S.M.B.ARoute d’ImouzzerBP 2427FezMorocco Physics department of the CRmEF TangierMorocco

This paper presents an annual performance evaluation of three maximum power point tracking (mPPT) methods. The used mPPT techniques (Perturb and Observe, Incremental Inductance and Sliding mode) are evaluated under an annual data of atmospheric conditions of the target site. The main contribution of this work is to consider real fluctuation conditions of solar irradiations, ambient temperatures and wind velocities. It was found that the Sliding mode provides higher energy yields independently of the period. Compared to the basic P&O and the IC techniques, sliding mode has the potential of generating up to 8.18% more electrical energy than other techniques.

关键词： Photovoltaic systems maximum power point tracking(mPPT) Annual performance

Optimization of AWJm Process Parameters on 3d-Printed Onyx-Glass Fiber Hybrid Composite

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Journal of Harbin Institute of Technology(New Series) 2023年第2期30卷 84-98页

作者： dharmalingam G Arun Prasad m deepak Panghal Sachin Salunkhe Siva kumar m Rathinasuriyan C department of mechanical Engineering Vel Tech Rangarajan Dr.Sagunthala R&D Institute of Science and TechnologyAvadiChennai-600062Tamil NaduIndia department of Fashion Technology National Institute of Fashion TechnologyNew Delhi-11016India

Compared with conventional manufacturing methods, the additive manufacturing technique enhances mechanical properties. The present investigation of additive manufacturing technique is focused on delamination studies of Onyx-Glass Fiber Hybrid Polymer Composite(OGFHPC) along with surface roughness properties during machining(drilling) of composites through abrasive water jet machining(AWJm). However, delamination is a major issue during machining of OGFHPC. In order to overcome these drawbacks, the fabrication of OGFHPC was carried out using fused deposition modeling(Fdm) technology which is an additive manufacturing method with mark forged mark Two 3d-composite printer. The machinability studies were conducted for drilling operation through AWJm process with different abrasive mass flow rates, drilling diameters and traverse speeds. These drilling machinability process parameters were optimized through the design of experiments-Taguchi analysis followed by the analysis of variance(ANOVA) and validated through the Harmony Search Algorithm(HSA), Whale Optimization Algorithm(WOA) and Grey Wolf Optimization Algorithm(GWO). It was observed that minimum delamination and surface roughness of OGFHPC were optimized for AWJm at abrasive mass flow rates(450 g/min), drilling diameters(12 mm) and traverse speed rate(30 mm/min).

关键词： Onyx-Glass composite fused deposition modeling AWJm delamination surface roughness Taguchi analysis

Local Embeddings of Some Families of Subgroups of Finite Groups

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Acta mathematica Sinica,English Series 2009年第6期25卷 869-882页

作者： A.BALLESTER-BOLINCHES Luis m.EZQUERRO Alexander N.SKIBA departament d'lgebra Universitat de València departamento department of mathematics Gomel State University F.Skorina

In this paper we study the influence of the partial cover and avoidance property on the subgroups of some relevant families of subgroups in a finite group.

关键词： Finite group cover-avoidance property p-supersoluble groups saturated formation

The Philippine National Collection of microorganisms (PNCm):Repository of microbial diversity of the Country

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Journal of Ocean University of Qingdao 2002年第1期1卷 101-104页

作者： monsalud R.G. magbanua F.O. Parungao m.P. Banaay C.G.B. Bayer m.H.d. Yap J.K. Tapay L.m. Philippine National Collection of microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms Philippine National Collection of Microorganisms National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines National Institute of Biotechnology & Applied Microbiology University of the Philippines Los Baos College Laguna 4031 Philippines

The prime function of the Philippine National Collection of microorganisms (PNCm), being the national repository of microbial strains, is to collect and preserve strains for their continued viability and availability for future use. To date, a total of 2144 strains of bacteria (1357), yeasts (250), filamentous fungi (377), algae (14), and strains still to be identified (146) are maintained at the PNCm. These are preserved and maintained using various methods which include modified liquid drying (lyophilization), ultra-low temperature (-70℃) storage in 10% glycerol, storage in sterile soil, distilled water and overlaying with mineral oil. Periodic viability testing is done to assess the stability of these preserved cultures under storage. Aside from preservation and maintenance of cultures, the PNCm is also involved in several research activities. One of these is the isolation, characterization and identification of some Vibrio isolates from the Philippines. details on this particular study is presented in this report.

关键词：收藏文化菲律宾人微生物多样性细菌

SnO2形貌调控及其对有机胺响应的电化学性能

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化工新型材料 2019年第S1期47卷 137-140页

作者：胥丽纯王征王丽杜宇轩 ahm.d m d.maruf 杜建平太原理工大学化学化工学院太原030024 气体能源高效清洁利用山西省重点实验室太原030024

利用水热和溶剂热法合成了纳米SnO2,通过X射线衍射仪、扫描电镜等手段对产物进行表征,进而研究了SnO2在检测胺类物质中的电化学传感性能。结果表明:通过优化合成条件可以调控SnO2的形貌,其形貌与胺的电化学响应值有一定的依赖关系。SnO... 详细信息

利用水热和溶剂热法合成了纳米SnO2,通过X射线衍射仪、扫描电镜等手段对产物进行表征,进而研究了SnO2在检测胺类物质中的电化学传感性能。结果表明:通过优化合成条件可以调控SnO2的形貌,其形貌与胺的电化学响应值有一定的依赖关系。SnO2纳米颗粒有利于检测三甲胺,而纳米颗粒组装的碗状SnO2对三乙胺响应较大,这意味着不同形貌的SnO2可以用于低浓度不同胺的电化学检测。

关键词：纳米SnO2 合成有机胺电化学传感

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中国深圳经济特区中的劳资关系与外国投资者

特区经济 1990年第5期 30-31+36页

作者： J·C·m·钱 ,N·Y·李 ,d·斯库利 ,高扬

作为广泛宣传的“开放政策”的一部分,中国建立了几个经济特区,并在1984年宣布了14个沿海城市为“开放城市”。建立这些经济特区的原因主要在于吸收先进的生产技术和现代管理技术,然而在香港投资者眼里,主要的吸引力在于充足和廉价的劳... 详细信息

作为广泛宣传的“开放政策”的一部分,中国建立了几个经济特区,并在1984年宣布了14个沿海城市为“开放城市”。建立这些经济特区的原因主要在于吸收先进的生产技术和现代管理技术,然而在香港投资者眼里,主要的吸引力在于充足和廉价的劳力,以及作为发展中国家中国的特惠关税。这些经济特区也可能被设想作为一个过濾器,使资产阶级成份不易侵入中国其他地方。深圳在几个经济特区中是最成功的一个,首要的原因在于它毗邻香港。当然,它的成功也可归于香港的大多数商业团体是由有中国南方的语言和风俗的中国人经营的。这个因素显然促进了商业活动的进行,而且当谈到在深圳的香港投资时,“外

关键词：外国投资者深圳经济特区外国认购者广东对外开放基地中华人民共和国劳资关系

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根据南加州的背景地震活动性估计地震危险性

世界地震译丛 2008年第3期39卷 1-11页

作者： m.d.Petersen m.S.Reichle 张力方中国地震局地壳应力研究所

通过分析南加州的历史地震活动性,找到了一种用6.5级或小于6.5级的背景地震活动性计算地震危险性的合理方法。该方法的基本假设是:未来地震在空间上将群集在4级或4级以上历史主震震中附近。通过分析加州去群集的地震目录,计算每个网格... 详细信息

通过分析南加州的历史地震活动性,找到了一种用6.5级或小于6.5级的背景地震活动性计算地震危险性的合理方法。该方法的基本假设是:未来地震在空间上将群集在4级或4级以上历史主震震中附近。通过分析加州去群集的地震目录,计算每个网格内的地震发生率,并对该发生率进行空间光滑处理,以预测未来地震的空间分布。为了寻找合适的空间光滑函数,我们研究了南加州地震震级与距离(r)的相关性,发现其遵循1/rμ幂次率关系,其中μ随着震级增大而增大。我们的研究结果表明,较大的地震在空间上比较小地震更群集。假设地震活动性遵从古登堡-里克特震级分布关系,我们计算了50年超越概率10%的地面峰值加速度。南加州大部分地区的峰值地面加速度值在0.25g至0.35g(g=10m/s2)之间。所得地震动水平一般比用全部震源模型(包括地质和大地测量资料)所得结果的一半还要小。我们还用蒙特卡罗方法计算了危险性图的总体不确定性,发现该地区大多数区域的变化系数为0.24±0.01。

关键词：地震危险性不确定性光滑函数背景地震活动地震动地震活动性小地震南加州危险性区划震级上限

高支化含无机粒子的巯基硅氧烷溶胶的制备及结构表征

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高分子材料科学与工程 2006年第4期22卷 134-137页

作者：贺建芸 mark d.Soucek 北京化工大学高性能UV材料研究室北京100029 美国阿克隆大学聚合物科学与工程学院

用溶胶-凝胶法制备了一种新型的多功能巯基硅氧烷溶胶,其结构用1H-Nm R,FT-IR和m S进行了表征,巯基硅氧烷溶胶的无机粒子粒径大小与分布用小角度光散射仪(SALS)进行了测定。这种新型巯基硅氧烷溶胶能够提高改性亚麻籽油体系自由基聚合... 详细信息

用溶胶-凝胶法制备了一种新型的多功能巯基硅氧烷溶胶,其结构用1H-Nm R,FT-IR和m S进行了表征,巯基硅氧烷溶胶的无机粒子粒径大小与分布用小角度光散射仪(SALS)进行了测定。这种新型巯基硅氧烷溶胶能够提高改性亚麻籽油体系自由基聚合速率。

关键词：巯基硅氧烷溶胶溶胶-凝胶法高支化多官能有机/无机混杂改性亚麻籽油