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Tribology of nitriding layer, TiN coatings and their complex on AISI D2 steel

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 383-385页

作者： WANG Ke-sheng ZHANG De-yuan DONG Ding-fu College of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Yu King Industrial Company Limited Shenzhen 518103 China College of Materials Science and Engineering Hefei University of Technology Hefei 230009 China National R&D Centre for Surface Engineering of China Shenzhen 518029 China College of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

The sliding wear and impact wear resistances of D2 steel with nitriding layer, PVD titanium nitride coating and their duplex treatment were investigated. The experimental results suggest that the duplex treatment has the best sliding and impact wear resistances under experimental conditions. And the wear resistance of PVD titanium nitride is better than that of nitriding. The impact wear resistance and wear mechanism of all three surface layers remain unchanged under impact load of 0.2 J or 1 J. All samples end with the same symptom of flaking.

关键词： wear resistance titanium nitride nitriding duplex treatment

Investigation on the synthesis conditions of poly(4-methyl-1-pentene)hollow fiber membrane with high gas permeability and strong tensile strength

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Chinese Journal of Chemical Engineering 2024年第11期75卷 25-34页

作者： Changfeng Lu Donghai sheng Lin Zhang Beibei Feng yuan Li State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Central Laboratory of Yongchuan Hospital Chongqing Medical UniversityChongqing 402160China

Poly(4-methyl-1-pentene)hollow fiber membranes(PMP HFMs)are commonly used in gas separation membrane and artificial lung membrane in extracorporeal membrane oxygenation(ECMO),and its porous structure and mechanical properties have a significant impact on the performance of the membrane *** our work,PMP HFMs were prepared by thermally induced phase separation ***,through characterization analysis of powder X-ray diffraction,universal tensile machine,scanning electron microscope and other instruments,the effects of PMP concentration,diluent ratio,quenching temperature,air gap distance and winding speed on the membrane performance were systematically investigated to obtain optimal preparation conditions for PMP *** results showed that the PMP HFMs prepared under optimal conditions possessed good gas permeability with a nitrogen flux of 10.5 ml·MPa^(-1)·cm^(-2)·min^(-1),a surface dense layer,and a good tensile strength of 9.33 *** believed that this work could provide useful references for the application of PMP membranes in the medical field.

关键词： Extracorporeal membrane oxygenation Poly(4-methyl-1-pentene)hollow fiber membranes Thermally induced phase separation Bicontinuous porous structure Gas permeability

Recent studies on potential accident-tolerant fuel-cladding systems in light water reactors

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Nuclear Science and Techniques 2020年第3期31卷 94-123页

作者： sheng-Li Chen Xiu-Jie He Cen-Xi yuan Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China Universite Grenoble Alpes I-MEP238402 Saint Martin d’HeresFrance

Accident-tolerant fuel(ATF)has attracted considerable research attention since the 2011 Fukushima nuclear *** improve the accident tolerance of the fuel-cladding systems in the current light-water reactors,it is proposed to develop and deploy(1)an enhanced Zrbased alloy or coated zircaloy for the fuel cladding,(2)alternative cladding materials with better accident tolerance,and(3)alternative fuels with enhanced accident tolerance and/or a higher U *** review presents the features of the current UO2-zircaloy *** techniques and characters to develop coating materials and enhanced Zr-based alloys are *** features of several selected alternative fuels and cladding materials are reviewed and *** neutronic evaluations of alternative fuel-cladding systems are *** is expected that one or more types of ATF-cladding systems discussed in the present review will be implemented in commercial reactors.

关键词： Accident-tolerant fuel Accident-tolerant cladding Light-water reactor Neutronic evaluation

Research on the Magnetic Field of NGC 7793 P13 and Other Confirmed Pulsating Ultraluminous X-Ray Sources

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Research in Astronomy and Astrophysics 2022年第11期22卷 207-213页

作者： Fan-Liang Meng yuan-Yue Pan Zhao-sheng Li Key Laboratory of Stars and Interstellar Medium Xiangtan UniversityXiangtan 411105China

A pulsating ultraluminous X-ray source(PULX)is a new kind of pulsar(PSR)whose characteristics are different from all known neutron *** magnetic field of PULX is suspected to be the main reason to support its supper Eddington luminosity of *** 7793 P13,which is the second confirmed PULX,can be easily studied due to its nearby position and isolation from other sources in its host *** this paper,we calculate its magnetic field to be∼1.0×10^(12) G based on the continued observations from 2016 to *** magnetic field evolution of NGC 7793 P13 is analyzed,which shows that the source has spent about 10^(4) yr for the field decaying from the simulated initial strength 4.0×10^(14) G to the present *** case of an assumed constant accretion and the limitation of the companion mass,it will be a recycled PSR whose magnetic field is ∼10^(9) G and spin period is a few hundred *** estimate the field strength of the other confirmed PULXs and find main range is 10^(13)-10^(14) *** positions of the magnetic field and spin period are around or below the *** is because these PULXs are in the binary systems and are with the spin-up rate that are 2-3 orders higher than the normal binary *** suggest that PULXs are the accreting magnetars whose multi-pole strong magnetic field can support the supper Eddington *** would be helpful for studying the evolution of the magnetars,the formation of the binary PSRs above the Eddington spin-up line,and the millisecond PSRs with the magnetic field stronger than ∼10^(9) G.

关键词： stars:neutronll(stars:)pulsars stars:evolution stars:magnetic field accretion accretion disks X-rays:bursts stars:magnetars

Optical properties of Al_(x)Ga_(1-x)As/GaAs Woods-Saxon quantum well in the presence of hydrostatic pressure and applied electric field

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Communications in Theoretical Physics 2022年第6期74卷 143-151页

作者： Zhi-Hai Zhang Yi-sheng Shi Jian-Hui yuan School of Physics and Electronics Yancheng Teachers UniversityYancheng 224002China Intelligent photoelectric device and measurement engineering research center Yancheng Teachers UniversityYancheng 224002China The Laboratory of Biomedical Photonics and Engineering Guangxi Medical UniversityNanning 530021China

The third harmonic generation(THG),linear and nonlinear optical absorption coefficients(OACs),and refractive index changes(RICs)are investigated in a Woods-Saxon quantum well(QW)modulated by the hydrostatic pressure and applied electric *** effect of non-uniform aluminum doping(position-dependent effective mass(PDEM))on the mass of the system is discussed,and further to explore the influence of PDEM on the nonlinear THG,OACs,and RICs of the Woods-Saxon *** nonlinear optical properties above are obtained using the compact-density matrix *** electron states in a Woods-Saxon QW under the constant effective mass(CEM)and PDEM are calculated by solving the Schr?dinger equation via the finite difference *** contributions from competing effects of the hydrostatic pressure and applied electric field to the nonlinear optical properties with CEM and PDEM are reported,as well as the comparison with each *** observations reveal that the regulation of external fields and the influence of PDEM play an important role in the photoelectric properties of QW.

关键词： optical properties position dependent effective mass hydrostatic pressure electric field

Responses of HFR-LWC beams under close-range blast loadings accompanying membrane action

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Defence Technology（防务技术） 2020年第6期16卷 1167-1187页

作者： Wan-xiang Chen Li-sheng Luo Zhi-kun Guo Peng yuan School of Civil Engineering Sun Yat-Sen UniversityZhuhai519082China State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai519082China

The load-carrying capacities and failure patterns of reinforced concrete components can be significantly changed by membrane ***,limited work has been carried out to investigate the blast resistance of Hybrid Fiber Reinforced Lightweight Aggregate Concrete(HFR-LWC)members accompanying membrane *** paper presents a theoretical approach to quantitatively depicting the membrane behavior and its contribution on the behavior of HFR-LWC beams under close-range blast loadings,and the suitability of the proposed model is validated by a series of field *** improved Single-Degree-of-Freedom(SDOF)model was employed to describe the dynamic responses of beam-like members under blast loadings accompanying membrane action,where the mass-load coefficient is determined according to the nonuniformly distributed load induced by close-range explosion,and the membrane action is characterized by an in-plane(longitudinal)force and a resisting *** elastoplastic and recovery responses of HFR-LWC beams under the combined action of blast load and membrane force were analyzed by the promoted model.A specially built end-constrain clamp was developed to provide membrane action for the beam member when they are subjected to blast load *** is demonstrated that the analytical displacement-time histories are in good agreement with experimental results before peak deflections and that the improved SDOF model is an acceptable tool for predicting the behavior of HFR-LWC beams under blast loadings accompanying membrane action.

关键词： Blast load Membrane action HFR-LWC beam Dynamic response Experimental study

Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-Fu Song yuan Chen sheng-Bao Shi School of Petroleum Engineering and Environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

Microstructural evolution and mechanical properties of 55NiCrMoV7 hot-work die steel during quenching and tempering treatments

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Advances in Manufacturing 2021年第4期9卷 520-537页

作者： Xing-sheng Yu Chuan Wu Ru-Xing Shi Ya-Sha yuan Luoyang CITIC HIC Casting&Forging Co. LtdLuoyang 471039HenanPeople’s Republic of China National-Local Joint Engineering Laboratory of Intelligent Manufacturing Oriented Automobile Die&Mould Tianjin University of Technology and EducationTianjin 300222People’s Republic of China CITIC Heavy Industries Co. LtdLuoyang 471039HenanPeople’s Republic of China

55NiCrMoV7 hot-work die steel is mainly used to manufacture heavy forgings in the fields of aerospace and *** study aims to clarify the effects of heat treatment on the microstructural evolution and mechanical properties of the steel,in order to find out an optimal heat treatment scheme to obtain an excellent balance of strength,ductility and *** steel was quenched at temperature from 790℃ to 910℃ followed by tempering treatments of 100–650℃ for 5 *** mechanical property tests were carried out by tensile,impact toughness and *** microscope(OM),scanning electron microscope(SEM)and transmission electron microscope(TEM)were used to observe the austenite grains,lath martensite,carbides and fracture *** results show that the quenching temperature mainly influences the austenite grain size and the volume fraction of undissolved carbides(UCs),while the tempering temperature mainly influences the size and morphology of the martensite with a body centered cubic(BCC)and the carbides with a face centered cubic(FCC).The mechanical properties of the steel,including yield and tensile strength,ductility,impact toughness and hardness,get an excellent balance at a quenching range of 850–870*** the tempering temperature increases,the yield and tensile strength and hardness decrease,while the ductility and impact toughness *** variation trends can be further verified by fracture SEM observation and *** with a macro-micro coupled finite element(MMFE)modeling technique,the cooling rate,microstructural evolution and yield strength of the steel were predicted and compared with the tested data.

关键词： Hot-work die steel Microstructural evolution Mechanical properties Heat treatment Macro-micro coupled modeling and simulation

Degradable preformed particle gel as temporary plugging agent for low-temperature unconventional petroleum reservoirs:Effect of molecular weight of the cross-linking agent

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Petroleum Science 2022年第6期19卷 3182-3193页

作者： Hong-Jun Zhang Dao-Yi Zhu Yong-Long Gong Jun-Hui Qin Xiao-Ning Liu yuan-Hang Pi Qi Zhao run-Tian Luo Wan-sheng Wang Ke-Ke Zhi Zong-Jie Mu China University of Petroleum-Beijing at Karamay KaramayXinjiang834000China

The development of unconventional petroleum resources has gradually become an important succession for increasing oil ***,the related engineers and researchers are paying more and more attention to the application of temporary plugging agents(TPAs)for their efficient *** can expand the stimulated reservoir volume(SRV)and facilitate the flow of oil and gas to the bottom of the ***-gels used as temporary plugging agents have the characteristics of the simple injection process,good deformation,high plugging strength,and complete self-degradation performance,which have been widely applied in recent *** this paper,five samples of DPPG polymerized by different molecular weights of cross-linking agents were *** addition,infrared spectroscopy analysis,differential calorimetry scanning(DSC)analysis,static particle gel swelling and degradation performance evaluation experiments,and dynamic temporary plugging performance experiments in cores were conducted at 34°*** show that as the molecular weight of the cross-linking agent(at 0.01 g)in the DPPG molecule decreased from 1,000 to 200 Da,the fewer cross-linking sites of DPPG,the looser the microscopic three-dimensional mesh structure *** swelling ratio increased from 7 to 33 ***,the complete degradation time increased from 40 to 210 ***,the DSC results confirmed that the higher the molecular weight of the cross-linking agent,the worse is chemical stability and the more prone it to *** samples had good temporary plugging performance in reservoir *** prepared by the cross-linking agent with smaller molecular weight has a stronger swelling ratio,higher gel strength,and greater plugging strength in the core ***,the degraded DPPG is less damaging to the ***,their slower degradation rates take a slightly longer times to reach complete *** results of this paper can provide new ideas and

关键词： Temporary plugging agent Preformed particle gel Degradable cross-linking agent Molecular weight Low-temperature reservoir