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Influence of Microstructures on Polarization Resistance and Hydrogen-Induced Cracking of a Micro-Alloyed Steel Submitted to different Cooling Rates

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Journal of Iron and Steel Research International 2011年第S1期18卷 168-172页

作者： González M R Martins de Araújo d S Goldenstein H Alonso-Falleiros N departamento de Engenharia Metalúrgica e de Materiais EscolaPolitécnicaUniversidade de Sao Paulo-SP-Brasil

The effect of different microstructures on the polarization resistance (Rp) and the hydrogen-induced cracking (HIC) of a micro-alloyed steel austenitized and submitted to different cooling rates was *** 19.1 x 6 x 2 mm,containing the whole thickness of the plate were extracted from a 20 mm plate and heat treated on a quenching dilatometer,were submitted to Rp and HIC corrosion *** Rp and HIC tests followed as close as possible ASTM G59 and NACE standard TM0284-2003,in this case,modified only with regard to the size of the *** samples transformed from austenite by a slow cooling (cooling rate of 0.5℃.s-1) showed higher susceptibility to hydrogen-induced cracking,with large cracks in the middle of the sample propagating along segregation bands,corresponding to the centerline of the plate *** cooling rates of 10℃.s-1,only small cracks were found in the matrix and micro cracks nucleated at non-metallic *** higher cooling rates (40℃.s-1) very few small cracks were detected,linked to non-metallic *** result suggests that structures formed by polygonal structures and segregation bands (were eutectoid microconstituents predominate) have higher susceptibility to *** predominantly formed by acicular ferrite make it difficult to propagate the cracks among non-oriented and interlaced acicular ferrite *** segregation bands containing eutectoid products also help inhibit cracking and crack propagation;segregation bands can function as pipelines for hydrogen diffusion and offer a path of stress concentration for the propagation of cracks,frequently associated to non-metallic *** resistance essays performed on the steel in theas received condition,prior to any heat treatment,showed larger differences between the regions of the plate,with a considerably lower Rp in the *** austenitization heat treatments followed by cooling rates of 0.5 e 10℃.s-1 made more uniform the

关键词： hydrogen induced cracking polarization resistance micro-alloyed steel control cooling

A robust test of uncertain linear systems

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控制理论与应用（英文版） 2009年第3期7卷 277-280页

作者： Yogesh V. HOTE d. Roy CHOUdHURY J. R. P. GUPTA department of Instrumentation and Control Engineering Delhi University department of Computer Engineering I. P. University

In this paper, it is shown that for low-order uncertain systems, there is no need to calculate all the minimum and maximum values of the coefficients for a perturbed system which is expressed in terms of polynomials and hence no need to formulate and test all the four Kharitonov＇s polynomials. Furthermore, for higher-order systems such as n ≥ 5, the usual four Kharitonov＇s polynomials need not be tested initially for sufficient condition of perturbed systems; rather, the necessary condition can be checked before going for sufficient condition. In order to show the effectiveness of the proposed method, numerical examples are shown and computational efficiency is highlighted.

关键词： Kharitonov's theorem Robust stability Routh criterion

Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole

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上海交通大学学报 2004年第z2期38卷 79-82页

作者： J.L.Song d.J.Hu Q.C.Wang H.Q.Chen H.G.Guo School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.

关键词： alternator claw-pole casting-forging near net forming numerical simulation

From dirac’s Aether to the dirac Equation

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第4期10卷 1450-1466页

作者： Richard d. Bateson Cavendish Laboratory Cambridge UK

In 1951, dirac proposed a formalism for a Lorentz invariant Aether with a vacuum state that contains all possible velocity states at each space-time point. dirac showed no explicit path from the Aether towards the Quantum Mechanics. In this paper, we demonstrate that dirac’s proposed Aether can be described by a lattice of possible events in space-time built in the local Lorentz frame. The idealised case of single velocity state leads to the famous dirac equation for a plane wave state and is compatible with quantum statistics. On the lattice, possible space-time events are connected by the dirac spinors which provide the probability of observing an event. The inertial mass of a particle is shown to be equivalent to the density of possible events on the lattice. Variation of the lattice density of events modifies the metric and provides a space-time curvature leading to the Hilbert action associated with general relativity. In classical limit, the perturbation in the density of possible events of the Aether is proportional to the Newtonian gravitational potential.

关键词： dirac Aether Lorentz Invariance dirac Equation Quantum Mechanics Space-Time Lattice dirac Spinors Inertial Mass Metric Modification Space-Time Curvature General Relativity

Effect of the catalyst preparation method on the performance of Ni-supported catalysts for the synthesis of saturated amines from nitrile hydrogenation

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Chinese Journal of Catalysis 2019年第11期40卷 1693-1703页

作者： d.J.Segobia A.F.Trasarti C.R.Apesteguía Catalysis Science and Engineering Research Group (GICIC) INCAPE UNL-CONICET CCT Conicet- Paraje El Pozo(3000) Santa Fe Argentina

The liquid-phase hydrogenation of butyronitrile to saturated amines was studied on silica- supported Ni catalysts prepared by either incipient-wetness impregnation (Ni/SiO2-I) or ammonia (Ni/SiO2-A) methods. A Ni/SiO2-Al2O3-I sample was also used. Ni/SiO2-I was a non-acidic catalyst containing large Ni^0 particles of low interaction with the support, while Ni/SiO2-A was an acidic catalyst due to the presence of Ni^2+ species in Ni phyllosilicates of low reducibility. Ni/SiO2-I formed essentially butylamine (80%), and dibutylamine as the only byproduct. In contrast, Ni/SiO2-A yielded a mixture of dibutylamine (49%) and tributylamine (45%), being the formation of butylamine almost completely suppressed. The selective formation of secondary and tertiary amines on Ni/SiO2-A was explained by considering that butylamine is not release to the liquid phase during the reaction because it is strongly adsorbed on surface acid sites contiguous to Ni^0 atoms, thereby favoring the butylimine/butylamine condensation to higher amines between adsorbed species.

关键词： Nitrile hydrogenation Saturated amines Ni-supported catalysts Ni-phyllosilicates Catalyst preparation

太阳能规划——通过地方政策与行动促进太阳能使用

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城市规划学刊 2014年第3期 124-125页

作者： MORLEY d

几个世纪以来,人类在规划居民聚居点和设计建筑物时通常都会考虑有利于太阳自然光热充分吸收的空间形态,但在化石燃料成为热力和电力的主要来源之后,很多此类设计手法被束之高阁。1970年代的能源危机推动了太阳能产品市场的兴起。近年来... 详细信息

几个世纪以来,人类在规划居民聚居点和设计建筑物时通常都会考虑有利于太阳自然光热充分吸收的空间形态,但在化石燃料成为热力和电力的主要来源之后,很多此类设计手法被束之高阁。1970年代的能源危机推动了太阳能产品市场的兴起。近年来,有关被动式和主动式太阳能设计的研究在美国和全球重新获得关注。本报告是美国能源部太阳计划(Sunshot Initiative)的一部分,该计划是一项致力于在2020年

关键词：太阳能地方政府城镇太阳辐射能气候资源美国规划师协会太阳能市场规划长远计划

Growth and Characterization of Organic NLO Crystal:β-Naphthol

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Journal of Materials Science & Technology 2011年第3期27卷 271-274页

作者： S.Janarthanan R.Sugaraj Samuel S.Selvakumar Y.C.Rajan d.Jayaraman S.Pandi department of Physics Presidency College department of Chemistry Presidency College department of Physics L.N.Govt.College department of Material Science Engineering National Chiao Tung University

Single crystals of β-Naphthol （/3N）, an organic nonlinear optical （NLO） material was successfully grown by temperature lowering method using chloroform as solvent. The initial compound was purified by repeated recrystallization process. As-grown crystals were characterized by single crystal X-ray diffraction （XRd） studies to ascertain that βN crystal crystallized in the monoclinic system with a noncemtrosymmetric space group. Vibrational frequencies of various functional groups in the crystals were derived from Fourier transform infrared （FTIR） spectroscopy and proton nuclear magnetic resonance （NMR） spectrum. Optical characterization was done using UV-Visible near-infrared （NIR） spectroscopy. The thermal behaviour of the material was studied by thermo gravimetric and differential thermal plots. Scanning electron microscopy （SEM） study was carried out on the surface of the grown crystals to investigate the nature of defects in the crystal surface and the NLO property of the crystal was tested by Nd：YAG laser as a source.

关键词： Crystal growth Fourier transform infrared (FTIR) spectroscopy Nonlinear optical crystal Scanning electron microscopy (SEM)

The role of RAd9 in tumorigenesis

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Journal of Molecular Cell Biology 2011年第1期3卷 39-43页

作者： Howard B.Lieberman Joshua d.Bernstock Constantinos G.Broustas Kevin M.Hopkins Corinne Leloup Aiping Zhu Center for Radiological Research Columbia University College of Physicians and Surgeons630 W.168th St.New YorkNY 10032USA department of Environmental Health Sciences Mailman School of Public Health722 W.168th St.New YorkNY 10032USA

RAd9 regulates multiple cellular processes that influence genomic integrity,and for at least some of its functions the protein acts as part of a heterotrimeric complex bound to HUS1 and RAd1 ***9 participates in dNA repair,including base excision repair,homologous recombination repair and mismatch repair,multiple cell cycle phase checkpoints and *** addition,functions including the transactivation of downstream target genes,immunoglobulin class switch recombination,as well as 3′–5′exonuclease activity have been *** RAd9 expression has been linked to breast,lung,thyroid,skin and prostate tumorigenesis,and a cause–effect relationship has been demonstrated for the latter ***,human RAd9 overproduction correlates with prostate cancer whereas deletion of Mrad9,the corresponding mouse gene,in keratinocytes leads to skin *** results reveal that RAd9 protein can function as an oncogene or tumor suppressor,and aberrantly high or low levels can have deleterious health *** is not clear which of the many functions of RAd9 is critical for carcinogenesis,but several alternatives are considered herein and implications for the development of novel cancer therapies based on these findings are examined.

关键词： RAd9 tumor suppressor oncogene tumorigenesis cell cycle checkpoints dNA repair

Influence of Carrier Gas on Analysis of MgO Powders by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

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Journal of Materials Science & Technology 2009年第3期25卷 333-335页

作者： J.S. Lee Y.S. Lee C.J. Park H.S. Lee d.S. Lee department of Chemistry Yonsei University Material Analysis Team Korea Testing Laboratory Korea Research Institute of Standards and Science School of Material Science and Engineering Pusan National Univirsity

Laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） has been widely adopted for the direct multi-elemental analysis with high sensitivity. Especially analysis of fine ceramics by LA-ICP-MS without time-consuming sample decomposition process has been one of the most expecting application field. Small additive elements in MgO powders were analyzed by LA-ICP-MS. For precise and accurate analysis influence of carrier gas （Ar or He） was presented by the signal intensities of ICP-MS, relative standard deviation of signal intensities and ablated particle size distribution. Ablated particles were collected and analyzed by scanning electron microscopy （SEM） to investigate the particle size distribution, and the ablated sample surface was examined by camscope. In He gas atmosphere, the signal was more stable than in Ar gas atmosphere. The signal intensity was higher in Ar than in He. Examination of ablated particles and sample surface reveals that more particles were generated in Ar atmosphere and the distribution of particle size was larger.

关键词： Laser ablation MgO powders Carrier gas ICP-MS