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International j.urnal of Coal Science & Technology 2016年第3期3卷 295-310页

作者： H. y. Liu Haoy. Han H. M. An j. j. Shi School of Engineering and ICT University of TasmaniaHobart TAS 7001 Australia School of Civil & Environmental Engineering University ofScience and Technology Beijing Beijing China

A hy.rid finite-discrete element method was implemented to study.the fracture process of rough rock j.ints under direct shearing. The hy.rid method reproduced the j.int shear resistance evolution process from asperity.sliding to degradation and from gouge formation to grinding. It is found that, in the direct shear test of rough rock j.ints under constant normal displacement loading conditions, higher shearing rate promotes the asperity.degradation but constraints the volume dilation, which then results in higher peak shear resistance, more gouge formation and grinding, and smoother new j.int surfaces. Moreover, it is found that the j.int roughness affects the j.int shear resistance evolution through influencing the j.int fracture micro mechanism. The asperity.degradation and gouge grinding are the main failure micro-mechanism in shearing rougher rock j.ints with deeper asperities while the asperity.sliding is the main failure micro-mechanism in shearing smoother rock j.ints with shallower asperities. It is concluded that the hy.rid finite-discrete element method is a valuable numerical tool better than traditional finite element method and discrete element method for modelling the j.int sliding, asperity.degradation, gouge formation, and gouge grinding occurred in the direct shear tests of rough rock j.ints.

关键词： Hy.rid FEM-DEM Rock j.int Asperity.sliding Asperity.shearing Fragment grinding

MICROWAVE PERMEABILITy.SPECTRA OF SPUTTERED Fe-Co-B SOFT MAGNETIC THIN FILMS

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 419-424页

作者： j.S. Liao Z.K. Feng j. Qiu y. Q. Tong Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Permeability.characteristics of sputtered soft magnetic Fe40Co40B20 thin films are investigated in the range of O. 5 to 5 GHz by.a shortened microstrip transmission line perturbation method. Excellent microwave permeability.is achieved at 0.4 Pa argon pressure： fr is 3.32 GHz, the real and imaginary.part of permeability.at 0.5 GHz are 104 and 61, respectively. In addition, the thickness effect on permeability.is also studied. The minimum damping can be achieved at the thinnest film. Different sources contributed to in-plane anisotropy.are discussed briefly. The deviation between the peak frequency.of the imaginary.part and the zero-crossing frequency.of the real part of permeability.is also presented.

关键词： Fe-Co-B In-plane anisotropy Magnetic thin films Permeability

Enzy.atic oxidation of aqueous pentachlorophenol

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j.urnal of Environmental Sciences 2007年第9期19卷 1032-1036页

作者： E. y. Kim H. j. Chae K. H. Chu Department of Chemical Engineering The University of Seoul Seoul 130-743 Korea. Departments of Food and Biotechnology.and Innovative Industrial Technology Hoseo University Asan 336-795 Korea Honey.ell Process Solutions 17 Changi Business Park Central 1 Singapore 486073

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation cataly.ed by.horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzy.e inactivation which occurred through a combination of free radical attack and sorption by.precipitated products. A simple first-order model was able to simulate time profiles for enzy.e inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably.through micelle partitioning of PCP which precluded the hy.rophobic PCP molecule from interacting with the enzy.e.

关键词： biocataly.is horseradish peroxidase pentachlorophenol surfactant

Micro-optical fabrication by.ultraprecision diamond machining and precision molding

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Frontiers of Mechanical Engineering 2017年第2期12卷 181-192页

作者： Likai LI Neil j. NAPLES j.ffrey.W. ROBLEE Allen y. y. Department of Integrated Sy.tem Engineering The Ohio StateUniversity Columbus OH 43210 USA Nistica Inc. Bridgewater NJ 08807 USA Ametek Precitech Keene NH 03431 USA

Ultraprecision diamond machining and high volume molding for affordable high precision high performance optical elements are becoming a viable process in optical industry.for low cost high quality.microoptical component manufacturing. In this process, first high precision microoptical molds are fabricated using ultraprecision single point diamond machining followed by.high volume production methods such as compression or inj.ction molding. In the last two decades, there have been steady.improvements in ultraprecision machine design and performance, particularly.with the introduction of both slow tool and fast tool servo. Today.optical molds, including freeform surfaces and microlens array., are routinely.diamond machined to final finish without post machining polishing. For consumers, compression mold- ing or inj.ction molding provide efficient and high quality.optics at extremely.low cost. In this paper, first ultrapreci- sion machine design and machining processes such as slow tool and fast too servo are described then both compression molding and inj.ction molding of poly.er optics are discussed. To implement precision optical manufacturing by.molding, numerical modeling can be included in the future as a critical part of the manufacturing process to ensure high product quality.

关键词： ultraprecision machining slow tool servo fast tool servo compression molding inj.ction molding,microlens array. optical fabrication

MICROSTRUCTURAL MODEL OF GATORIZED WASPALOy.IN THE ISOTHERMAL FORGING PROCESS

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Acta Metallurgica Sinica(English Letters) 2001年第3期14卷 205-211页

作者： j.P. Hu (Chongqing Iron and Steel Designing Research Institute, Chongqing 400013, China) j. y. Zhuang, j.H. du, Q. Deng, D. Feng and Z. y. Zhong (Central Iron and Steel Research Institute, Beij.ng 100081, China) P. j.nschek and j. Kramer (Thy.sen Umformte Central Iron and Steel Research Institute

A microstructural model, which was used to predict the evolution of microstructure of Gatorized Waspaloy.in the isothermal forging process, was developed in terms of dy.amic recry.tallization and grain growth. The following three steps of experiment were conducted during developing the model. (1) Specimens were compressed in the MTS testing machine. (2) Dy.amic recry.tallization and grain growth were discussed. (3) Dy.amic recry.tallization model and grain growth model were set up. The simulated results are in good agreement with the experimental data.

关键词： Forging Grain growth Microstructure Models Nickel alloy.

RELATIONSHIP BETWEEN INFRARED RADIATION AND CRy.TAL STRUCTURE IN Fe-Mn-Co-Cu-O SPINELS

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 15-20页

作者： y. Zhang D.j. Wen School of Material Engineering Soochow University Suzhou 215021 China

Ni^3＋ and Cr^3＋ doped Fe-Mn-Co-Cu-O spinels have been prepared by.solid phase sintering. The valence states and distribution of transition ions in the spinel cry.tals are inferred by.the consideration of thermody.amic principle and cry.talline field theory. The mierostructure and performance of those are studied by.X-ray.diffraction （XRD）, Fourier transform infrared （FT-IR）, and IRE-2 infrared radiant instrument. Ni3＋ and Cr3＋ occupy.the vacancies or substitute the other ions in the spinel structures and form diverse spinel structures, which exhibit infrared integral emissivities of 0.93 in the whole band, and 0. 94 in the band within 14-25μm too. The content of Fe2O3 and MnO2 in the spinel cry.tals changes, may.e it induces infrared radiativity.of spinels differently.

关键词： Cry.tal structure Mineral Infrared radiation property

FROM CRy.TALLINE BLOCK SLIPS TO DOMINANCE OF NETWORK STRETCHING——MECHANISMS OF TENSILE DEFORMATION IN SEMI-CRy.TALLINE POLy.ERS

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Chinese j.urnal of Poly.er Science 2002年第2期20卷 160-170页

作者： y. Men Univ Freiburg Fak Phys D-79104 Freiburg Germany

The mechanism of tensile deformation in semi-cry.talline poly.ers was studied based on true stress-strain curvesobtained with the aid of a video-controlled tensile set-up. The deformation is affected by.both the cry.talline and theamorphous phases. However, the relative weights of the two portions change with the deformation stage. At lowdeformations the coupling and coarse slips of the cry.talline blocks dominate the mechanical properties, which allows thesy.tem to maintain a homogeneous strain distribution in the sample. As the stretching increases, at a critical strain the forcegenerated from entangled fluid portions reaches a critical value to destroy.the cry.tallites. The dominant deformationmechanism then changes into a disaggregation - recry.tallization process.

关键词： Semi-cry.talline poly.er Deformation mechanism Network Mechanical property

Nitrogen Contents on Tribological Properties of Magnetron Sputtered SICN Coatings

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材料热处理学报 2004年第05B期25卷 854-857页

作者： TIETUNSUN y.Q.FU j.WEI H.j.du Departmentofphy.ics ShanghaiJiaotongUniversityShanghaiChina／／SchoolofMechanicalandProductionEngineeringNanyangTechnologicalUniversitySingapore639798 SchoolofMechanicalandProductionEngineering NanyangTechnologicalUniversitySingapore639798／／SingaporeInstituteofManufacturingTechnologySingapore71NanyangDriveSingapore638075 SingaporeInstituteofManufacturingTechnology -Singapore71NanyangDrivesingapore638075

Silicon carbonitride (SiCN) coatings were deposited on silicon and tungsten carbide substrates by.co-sputtering silicon and carbon in argon and nitrogen mixture atmosphere using magnetron-sputtering sy.tem. The effect of the N2 concentration, RF substrate bias voltage and target current on film deposition rate, roughness, adhesion, mechanical and tribological properties of coatings were investigated. The deposition rate was found to increase with the increasing nitrogen concentration. X-ray.photoelectron spectroscopy.analy.is showed that high nitrogen concentration in the nitrogen-argon gas mixture enhanced the incorporation of C and N but reduced the incorporation of Si. SiCN coatings have good tribological properties at a N2 concentration of approximately.60%.

关键词： SiCN涂层磁控管溅射含氮量硬度磨损

AGE STRENGTHENING OF DIFFUSION WELDED j.INT OF Al_2O_(3p)/6061Al COMPOSITE

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 18-22页

作者： j. T. Niu y. H. Tian B. y. Li j. j. Xu L.M. Liu (National Key.Laboratory.of Advanced welding Production Technology. HIT, Harbin 150001, China)

Tensile strength of diffusion welded j.int of aluminum matrix composite is very.low due to its poor weld- *** this paper, solution and age treatments were conducted on the welded j.int of Al2O3p/ 6061Al composite subj.cted to diffusion welding using Gleeble 1500 machine, and ensile strength and microstructure of welded j.int aged at175℃ were measured and analy.ed respectively. Results showed that aging precipitation of welded j.int is promoted effectively.because of redistribution of reinforcement and a few number of dislocations in the matrix of weld zone resulting from welding pressure,and hence tensile strength of welded j.int is increased significantly.after aging treatment.

关键词： aluminum matrix composite diffusion welding aging

Search for Double γ-Vibrational Bands in Neutron-Rich ^105Mo Nucleus

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Chinese Phy.ics Letters 2006年第12期23卷 3222-3225页

作者：丁怀博朱胜江 j. H. Hamilton A. V. Ramay.a j. K. Hwang y. X. Luo j. O. Rasmussen I. y. Lee 车兴来陈永静李明亮 Department of Phy.ics Tsinghua University Beijing 100084 Department of Phvsics Vanderbilt University Nashville Tennessee 37235 USA Lawrence Berkeley.National Laboratory Berkeley California 94720 USA

Levels in the neutron-rich ^105Mo nucleus have been investigated by.observing prompt γ-ray. following the spontaneous fission fragments of^252 Cf with the Gammasphere detector array. The y.ast band has been confirmed and updated. The other two collective bands with the band head levels at 870.5 and 1534.6 keV are newly.observed, and they.are suggested as the candidates for one-phonon K= 9/2 and two-phonon K = 13/2 double γ-vibrational bands, respectively. Sy.tematic characteristics of these bands have been discussed.

关键词： Double γ-Vibrational Bands Sy.tematic characteristics