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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 439-443页

作者： Mi-qi Wang ze-hua zhou Lin-tao Wu Ying Ding ze-hua Wang College of mechanics and materials Hohai University

The precursor carbonization method was first applied to prepare W–C compound powder to perform the in-situ synthesis of the WC phase in a Fe-based alloy coating. The in-situ formation mechanism during the cladding process is discussed in detail. The results reveal that fine and obtuse WC particles were successfully generated and distributed in Fe-based alloy coating via Fe/W–C compound powders. The WC particles were either surrounded by or were semi-enclosed in blocky M7C3 carbides. Moreover, net-like structures were confirmed as mixtures of M23C6 and α-Fe; these structures were transformed from M7C3. The coarse herringbone M6C carbides did not only derive from the decomposition of M7C3 but also partly originated from the chemical reaction at the α-Fe/M23C6 interface. During the cladding process, the phase evolution of the precipitated carbides was WC → M7C3 → M23C6 ＋ M6C.

关键词： precursor carbonization tungsten carbide (WC) microstructure in-situ formation mechanism phase evolution

Self-folding mechanics of graphene tearing and peeling from a substrate

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Frontiers of physics 2018年第3期13卷 17-28页

作者： ze-zhou He Yin-Bo Zhu Heng-An Wu CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China

Understanding the underlying mechanism in the tearing and peeling processes of graphene is crucial for the further hierarchical design of origami-like folding and kirigami-like cutting of graphene. How- ever, the complex effects among bending moduli, adhesion, interlayer interaction, and local crystal structure during origami-like folding and kirigami-like cutting remain unclear, resulting in challenges to the practical applications of existing theoretical and experimental findings as well as to potential manipulations of graphene in metamaterials and nanodevices. Toward this end, classical molecular dynamics （MD） simulations are performed with synergetie theoretical analysis to explore the tearing and peeling of self-folded graphene from a substrate driven by external force and by thermal activation. It is found that the elastic energy localized at the small folding ridge plays a significant role in the crack trajectory. Due to the extremely small bending modulus of monolayer graphene, its taper angle when pulled by an external force follows a scaling law distinct from that in case of bilayer graphene. With the increase in the initial width of the folding ridge, the self-folded graphene, motivated by thermal fluctuations, can be self-assembled by spontaneous self-tearing and peeling from a substrate. Simultaneously, the scaling law between the taper angle and adhesive energy is independent of the motivations for thermal activation-induced self-assembly and external force tearing, providing effective insights into the underlying physics for graphene-based origami-like folding and kirigami-like cutting.

关键词： graphene tearing self-assembly elastic energy molecular dynamics simulation

Development path of Chinese low-carbon cities based on index evaluation

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Advances in Climate Change Research 2018年第2期9卷 144-153页

作者： YANG Xiu WANG Xue-Chun zhou ze-Yu National Center for Climate Change Strategy and International Cooperation Beijing 100038 China

This work takes the 36 cities from China＇s low-carbon pilot project as the research object and uses the carbon emission per capita and GDP per capita to categorize the 36 cities into four types to reveal their low-carbon development status; these four types are leading cities, developing cities, latecomer cities, and exploring cities. On the basis of an index system that quantitatively describes low-carbon development, this research analyzes the characteristics, development trends, and low-carbon development pathways of the four types of cities. According to the present situation and objectives of national emissions and considering the differences in development stages, challenges, and opportunities for each type of the city, this research presents recommendations for the low-carbon roadmap and the medium- and long-term （by 2030） emission trend routes of different types of regions in China.

关键词： City Low-carbon development Index evaluation Development path

Corrosion behavior of Al-3.0 wt%Mg alloy in NaCl solution under magnetic field

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Rare Metals 2017年第8期36卷 627-634页

作者： Xin Zhang ze-Hua Wang ze-Hua zhou Jian-Ming Xu Zhao-Jun Zhong Huan-Long Yuan College of Mechanics and Materials Hohai UniversityNanjing 210098China Zhangjiagang Hongji Aluminum Co.Ltd. Suzhou 215600China

The influences of applied magnetic field on the corrosion behavior of Al-3.0 wt%Mg alloy in 3.5 wt% NaCl solution were investigated by electrochemical measurements,scanning electron microscopy（SEM）and energy-dispersive spectroscopy（EDS）.Stochastic analysis was applied to investigate the influences of applied magnetic *** results indicate that the application of horizontal magnetic field of 0.4 T would increase the pitting corrosion potential（E_（pit））,decrease the corrosion current density（i_（corr））,prolong the pit initiation time,slow down the pit generation rate and inhibit the growth of pitting of the tested alloys in 3.5 wt% NaCl *** applied magnetic field would also change the mechanism of pit initiation of Al-3.0 wt%Mg alloy from A_3 model（without magnetic field）to A_3＋A_4 model（with magnetic field）.The intermediate product Al_（（ad））~＋ is the paramagnetic ion that would be influenced by magnetic field sensitively.

关键词： Al-3.0 wt%Mg alloy Applied magnetic field Pitting corrosion Paramagnetic ion

Feasibility for Testing the Equivalence Principle with Optical Readout in Space

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Chinese Physics Letters 2011年第8期28卷 16-19页

作者： GAO Fen zhou ze-Bing LUO Jun School of Physics Huazhong University of Science and TechnologyWuhan 430074

A concept of testing the equivalence principle with optical readout in space(TEPO)has been proposed[*** Appl.25(2008)423].We further discuss the feasibility of TEPO using LISA(laser interferometer space antenna)Pathfinder technologies,such as a heterodyne interferometer,an inertial sensor,drag-free control and discharge technique,and determine that the equivalence principle could be tested at 8×10^(−17) with one day integration.

关键词： interferometer antenna Pathfinder

In situ synthesis of Fe-based alloy clad coatings containing TiB_2–TiN –(h-BN)

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 613-619页

作者： Shao-qun Jiang Gang Wang Qing-wen Ren Chuan-duo Yang ze-hua Wang and ze-hua zhou College of Mechanics and Materials Hohai University Changzhou Hohai Institute of Science and Technology Limited Liability Company

Fe-based alloy coatings containing TiB2–TiN –（h-BN） were synthesized in situ on Q235 steel substrates by a plasma cladding process using the powders of Fe901 alloy, Ti, and h-BN as raw materials. The effects of Ti/h-BN mass ratio on interfacial bonds between the coating and substrate along with the microstructures and microhardnesses of the coatings were investigated. The results show that the Ti/h-BN mass ratio is a vital factor in the formation of the coatings. Free h-BN can be introduced into the coatings by adding an excess amount of h-BN into the precursor. Decreases in the Ti/h-BN mass ratio improve the microstructural uniformity and compactness and enhance the interfacial bonds of the coatings. At a Ti/h-BN mass ratio of 10/20, the coating is free of cracks and micropores, and mainly consists of Fe-Cr, Fe3B, TiB2, TiN, Ti2N, TiB, FeN, FeB, Fe2B, and h-BN phases. Its average microhardness in the zone between 0.1–2.8 mm from the coating surface is about Hv0.2 551.5.

关键词： iron-based materials coatings plasma cladding in situ synthesis microhardness

Essential Norms of Weighted Composition Operators from Weighted Bergman Space to Mixed-norm Space on the Unit Ball

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Acta Mathematica Sinica,English Series 2013年第3期29卷 547-556页

作者： ze Hua zhou Yu Xia LIANG Hong Gang zeNG Department of Mathematics Tianjin University

In this paper, we characterize the boundedness and compactness of the weighted composi- tion operators from the weighted Bergman space to the standard mixed-norm space or the mixed-norm space with normal weight on the... 详细信息

关键词： Weighted composition operator weighted Bergman space mixed-norm space essentialnorm compact

Fabrication and characterization of Al_2O_3-metal composite coating on steel plate with nonpressure combustion synthesis

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Rare Metals 2013年第4期32卷 390-396页

作者： Chang-Hao Wang ze-Hua Wang ze-Hua zhou Shao-Qun Jiang Xiao-Feng Xue Jing-Jing Yao College of Mechanics and Materials Hohai University School of Materials Science and Engineering Shanghai University

Al2O3-metal composite coatings with different reactants and diluents were fabricated on mild steel plate with nonpressure combustion synthesis process. The coat-ings were characterized by means of X-ray diffraction, scanning electron microscopy, and energy-dispersive spec-trometry, respectively. Thermal shock tests were carried out to determine the bond strength of the coating with the steel substrate. The results indicate that the coating is composed of α-A1203, α-（Fe-Cr） and Al2SiO5 as the main phases. It is found that the coating with the diluents of Al2O3-SiO2 and transition layer of Al2O3-Cr presents the *** hardness of 2270 HV0.2 and the lowest porosity of 3.93 %. Owing to a metallurgical bond of the coating-to-substrate, the coating exhibits a good thermal shock resistance.

关键词： Combustion synthesis Al2O3-metalcomposite coating Diluents Thermal shock resistance

Differences in clinical and genetic characteristics between early-and late-onset narcolepsy in a Han Chinese cohort

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Neural Regeneration Research 2020年第10期15卷 1887-1893页

作者： Hui Ouyang Fang Han ze-Chen zhou Jun Zhang Department of Clinical Neurology Peking University People’s HospitalBeijingChina Department of Clinical Pulmonology Peking University People’s HospitalBeijingChina Department of Epidemiology and Biostatistics School of Public HealthPeking University Health Science CenterBeijingChina

Early-and late-onset narcolepsy constitutes two distinct diagnostic ***,it is not clear whether symptomology and genetic risk factors differ between early-and late-onset *** study compared clinical data and single-nucleotide polymorphisms(SNPs)between early-and late-onset patients in a large cohort of 899 Han Chinese narcolepsy ***,cerebrospinal fluid,and clinical data were prospectively collected from patients,and patients were genotyped for 40 previously reported narcolepsy risk-conferring *** risk scores(GRSs),associations of five different sets of SNPs(GRS1–GRS5)with early-and late-onset narcolepsy,were evaluated using logistic regression and receiver operating characteristic *** sleep latency was significantly shorter in early-onset cases than in late-onset *** severity was greater among late-onset patients,with higher rates of sleep paralysis,hypnagogic hallucinations,health-related quality of life impairment,and concurrent presentation with four or more *** levels did not differ significantly between early-and late-onset *** rs3181077(CCR1/CCR3)and rs9274477(HLA-DQB1)were more prevalent among early-onset *** GRS1(26 SNPs;OR=1.513,95%CI:0.893–2.585;P<0.05)and GRS5(6 SNPs;OR=1.893,95%CI:1.204–2.993;P<0.05)were associated with early-onset narcolepsy,with areas under the receiver operating characteristic curves of 0.731 and 0.732,*** GRS1 nor GRS5 included SNPs in HLA *** results indicate that symptomology and genetic risk factors differ between early-and late-onset *** protocol was approved by the Institutional Review Board(IRB)Panels on Medical Human Subjects at Peking University People’s Hospital,China(approval *** 86)in October 2011.

关键词： case-control studies clinical features genetic association studies genetic load genetic loci genetic phenomena hypothalamic diseases precision medicine risk assessment single nucleotide polymorphism

On the Significance of Reference System for Active Damping of Vibration Isolators in Gravitational Wave Detection

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Chinese Physics Letters 1999年第5期16卷 324-326页

作者： zhou ze-bing LUO Jun FAN Shu-hua Department of Physics Huazhong University of Science and TechnolowWuhan 430074

Several active damping methods corresponding to various reference systems are *** theoretical analyses show that a quasi-fixed reference system can be used to improve the high-frequency performance of a multi-stage active damping system because its high-frequency performance is equivalent to that of a low-pass electronic filter with a very low cut-off frequency.

关键词： reference Reference system