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Enhanced thermoelectric properties of Cu_(3)SbSe_(4)-based materials by synergistic modulation of carrier concentration and phonon scattering

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Journal of Materiomics 2024年第2期10卷 339-347页

作者： Sitong Wei Zhen Ji Wenhao li Shuqi Zheng qing Wang Zhiliang li Lu Yu Sitong Luo Weiyu Song College of New Energy and Materials China University of PetroleumBeijing102249China College of Science China University of PetroleumBeijing102249China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province College of Physics Science and TechnologyHebei UniversityBaoding071002China

Cu_(3)SbSe_(4),a copper-based sulfide free of rare earth elements,has received extensive attention in ther-moelectric ***,its low carrier concentration restricts its widespread *** this study,a microwave-assisted solution synthesis method was used to produce samples of Cu_(3)SbSe_(4),which enabled the formation of CuSe in situ and increased the *** the use of first-principles cal-culations,structural analysis,and performance evaluation,it was found that CuSe can enhance the carrier concentration and that induced nano-defects have a positive effect on reducing the lattice thermal ***,doping with Sn decreases the band gap of the system and moves the Fermi level into the valence band,increasing the carrier concentration to 1.15×10^(-20)cm^(-3).Finally,the zT value of the Cu_(3)Sb_(0.98)Sn_(0.02)Se_(4)sample was achieved at 1.05 at 623 K when the theoretical yield of a single synthesis was 10 mmol.

关键词： Cu_(3)SbSe_(4) Carrier concentration Phonon scattering Synergistic modulation

Effect of Microstructures on Corrosion Behavior of Nickel Coatings:(Ⅰ) Abnormal Grain Size Effect on Corrosion Behavior

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Journal of Materials Science & Technology 2015年第12期31卷 1186-1192页

作者： Guozhe Meng Yang li Yawei Shao Tao Zhang Yanqiu Wang Fuhui Wang Xuequn Cheng Chaofang dong Xiaogang li Corrosion and Protection Laboratory Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University)Ministry of Education Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of Sciences Corrosion and Protection Center University of Science and Technology Beijing

Nickel coatings with different microstructures were synthesized by pulse jet electrodeposition *** morphology and microstructure were investigated by scanning electron microscopy（SEM）and transmission electron microscopy（TEM）.The corrosion property of the coatings was studied by using polarization,electrochemical impedance spectroscopy（EIS）,potential of zero free charge（PZFC） measurements and Mott-Schottky（M-S） *** results showed that the coating with grain size of 50 nm possessed higher corrosion resistance than that with grain size of 10 *** abnormal behavior may be related to the existence of nanoscale twins in the coatings and the lower concentration of acceptor in the passive films.

关键词： Nanocrystalline Pulse jet electrodeposition Corrosion Grain size Growth twins

Endoscopic ultrasound-guided ethanol ablation therapy for tumors

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World Journal of Gastroenterology 2013年第22期19卷 3397-3403页

作者： Wen-Ying Zhang Zhao-Shen li Zhen-dong Jin Department of Gastroenterology Changhai Hospital Second Military Medical University

Endoscopic ultrasonography (EUS) has evolved into a useful therapeutic tool for treating a broad range of tumors since being introduced into clinical practice as a diagnostic modality nearly three decades ago. In particular, EUS-guided fine-needle injection has proven a successful minimally invasive approach for treating benign lesions such as pancreatic cysts, relieving pancreatic pain through celiac plexus neurolysis, and controlling local tumor growth of unresectable malignancies by direct delivery of anti-tumor agents. One such ablative agent, ethanol, is capable of safely ablating solid or cystic lesions in hepatic tissues via percutaneous injection. Recent research and clinical interest has focused on the promise of EUS-guided ethanol ablation as a safe and effective method for treating pancreatic tumor patients with small lesions or who are poor operative candidates. Although it is not likely to replace radical resection of localized lesions or systemic treatment of metastatic tumors in all patients, EUS-guided ablation is an ideal method for patients who refuse or are not eligible for surgery. Moreover, this treatment modalitymay play an active role in the development of future pancreatic tumor treatments. This article reviews the most recent clinical applications of EUS-guided ethanol ablation in humans for treating pancreatic cystic tumors, pancreatic neuroendocrine tumors, and metastatic lesions.

关键词： Endoscopic ultrasonography Ethanol Tumor ablation Pancreas cancer Cystic tumor Neuroendocrine tumors Celiac plexus neurolysis

Carbides precipitation and their evolution of Cr15Co10Mo5-alloyed heat-resistant bearing steel after tempering at different temperatures

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Journal of Iron and Steel Research International 2019年第10期26卷 1096-1105页

作者： Mao-guo Xiao Xin-yang Lü dong-hui li Shao-hong li Kun-yu Zhao Mao-sheng Yang School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The carbides precipitation and their evolution at elevated tempering temperature in Crl5Col0Mo5-alloyed heat-resistant bearing steel were investigated by means of the transmission electron *** results show that there is no carbide precipitated from the martensitic matrix when the sample was tempered at 480℃.However,when the sample was tempered at 540℃,a large number of stable spherical M6C carbides precipitated in the test ***,there are three types of carbides precipitated from the matrix including M6C,M2C and M23C6 carbides when the tempering temperature reached 600℃.The mechanical properties also present a correlation with the evolution of carbides during tempering at different *** indicates that the strengthening mechanism of the steel is mainly attributed to the precipitation of carbides and their evolution,including the morphologies and types of carbides at different *** addition,the austenitic layers with a thickness of about 30 nm have been obtained between the martensite laths after tempering at 600℃.The austenitic layers will produce transformation-induced plasticity effects to improve the toughness of the steel.

关键词： High-temperature bearing steel Carbide evolution Phase diagram Diffusion coefficient Secondary hardening Austenitic layer

Total ionizing dose and synergistic effects of magnetoresistive random-access memory

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Nuclear Science and Techniques 2018年第8期29卷 136-140页

作者： Xing-Yao Zhang Qi Guo Yu-dong li lin Wen Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Technical Institute of Physics and ChemistryChinese Academy of SciencesUrtimqi 830011China Xinjiang Key Laboratory of Electronic Information Materialand Device Urumqi 830011China

A magnetoresistive random-access memory(MRAM) device was irradiated by ^(60) Co c-rays and an electron *** synergistic effect of this on the MRAM was tested with an additional magnetic field during irradiation,from which the total ionizing dose(TID) and the synergistic damage mechanism of MRAM were *** addition,DC,AC,and functional parameters of the memory were tested under irradiation and annealing via a very large-scale integrated circuit test *** radiation-sensitive parameters were obtained through analyzing the *** of the magnetic field applied on the MRAM while testing the synergistic effects,shallow trench isolation leakage and Frenkel–Poole emission due to synergistic effects were smaller than that of TID,and hence radiation damage of the synergistic effects was also lower.

关键词：随机存取剂量电离记忆集成电路测试 MRAM TID 存储器

light Scattering Microscopy of Surface and Its Computational Simulation

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Chinese Physics Letters 1999年第6期16卷 397-399页

作者： CHENG Chuan-fu liU De-li QI dong-ping Department of Physics Shandong Normal UniversityJi'nan 250014

The light scattering microscopy is proposed,which reconstructs the height distribution function of a random surface from the speckle intensity of the scattered light *** the computational simulation,we generated the random surfaces of Gaussian correlation and the speckle intensities,and reconstructed the surfaces by Gerchberg-Saxton(G-S)and modified G-S *** simulation proves this microscopy works well.

关键词： wave. speckle random

Anisotropic corrosion behavior of sintered(Ce_(0.15)Nd_(0.85))_(30)Fe_(bal)B permanent magnets

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Journal of Rare Earths 2019年第3期37卷 287-291页

作者： Xiaoning Shi Minggang Zhu dong Zhou Zheng Jing Meiling Zhang Wei li Division of Functional Material Central Iron & Steel Research Institute

In this work, the corrosion behavior of the surface parallel to the oriented c-axis(c‖) and perpendicular to c-axis(c⊥)in the(Ce_(0.15)Nd_(0.85))_(30)Fe_(bal)B dual main phase magnet was studied. With the addition of Ce,the volume fraction of RE-rich phase shown in the backscattered electron(BSE) images is basically approximate on the two surfaces. The free corrosion potential(E_(corr)) of the c‖ surface is more negative,which shows the worse corrosion resistance from the perspective of thermodynamics. While the reaction kinetics parameters with the smaller free corrosion current(i_(corr)) and the larger transfer resistance(R_(ct)) react the opposite conclusion in 3.5 wt% NaCl solution. Moreover, the c‖ surface performs smaller ions concentration of corrosion product and less damaged corrosion morphology compared to c⊥ surface after the free corrosion. The inconformity is not affected by the RE-rich phase, but by the anisotropy of the grains that the c‖ surface has larger density of the atoms and the lower ratio of(Nd, Ce)/Fe.

关键词： Sintered Nd-Fe-B Ce Dual main phase Anisotropic Electrochemistry Corrosion

Distribution of avian influenza viruses according to environmental surveillanee during 2014-2018, China

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Infectious Diseases of Poverty 2021年第3期10卷 99-100页

作者： Hong Bo Ye Zhang li-Bo dong Jie dong Xi-Yan li Xiang Zhao Zi li Yue-Long Shu Da-Yan Wang Nation al Institute for Viral Disease Control and Preve ntion Chinese Center for Disease Control and PreventionWHO Collaborating Center for Reference and Research On InfluenzaKey Laboratory for BiosafetyNational Health CommissionBeijingChina 不详

Background:Recurrent infections of animal hosts with avian influenza viruses(AIVs)have posted a persistent *** is very important to understand the avian influenza virus distribution and characteristics in environment associated with poultry and wild *** aim of this study was to analyze the geographic and seasonal distributions of AIVs in the 31 provinces,municipalities and autonomous region(PMA)of China,compare the AIVs prevalence in different col-lecting sites and sampling types,analyze the diversity of AIVs subtypes in environment.

关键词： Avian influenza virus live poultry market Environment Surveillanee

A new data structure for accelerating kinetic Monte Carlo method

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Research in Astronomy and Astrophysics 2019年第12期19卷 235-244页

作者： Xu-li Zheng dong-Hui Quan Hai-Long Zhang Xiao-Hu li Qiang Chang Olli Sipila Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Department of Chemistry Eastern Kentucky UniversityRichmondKYUSA Max-Planck-Institute for Extraterrestrial Physics(MPE) Giessenbachstr.185748 GarchingGermany School of Astronomy and Space Science University of Chinese Academy of SciancesBeijing 100049China

The kinetic Monte Carlo simulation is a rigorous numerical approach to study the chemistry on dust grains in cold dense interstellar clouds. By tracking every single reaction in chemical networks step by step, this approach produces more precise results than other approaches but takes too much computing time. Here we present a method of a new data structure, which is applicable to any physical conditions and chemical networks, to save computing time for the Monte Carlo algorithm. Using the improved structure,the calculating time is reduced by 80 percent compared with the linear structure when applied to the osu-2008 chemical network at 10K. We investigate the effect of the encounter desorption in cold cores using the kinetic Monte Carlo model with an accelerating data structure. We found that the encounter desorption remarkably decreases the abundance of grain-surface H2 but slightly influences the abundances of other species on the grain.

关键词： astrochemistry molecular processes methods:numerical ISM:molecules ISM:abundances