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China Foundry 2021年第1期18卷 9-17页

作者： he-shuai yu Xue-feng Guo Hong-bao Cui School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuoHenan454000China henan International Joint Research Laboratory for High-Performance Light Metallic Materials and Numerical Simulations Henan Polytechnic UniversityJiaozuoHenan454000China

The microstructures and mechanical properties of as-cast Mg-5 Sn-1 Si magnesium alloy modified with trace elements Y,Bi,Sb and Sr were investigated and *** show that the microstructure of the as-cast Mg-5 Sn-1 Si alloy consists ofα-Mg,Mg_(2) Si,Mg_(2) Sn and Mg_(2)(Si_xSn_(1-x))*** adding 0.8 wt.%Y,0.3 wt.%Bi,0.9 wt.%Sb and 0.9 wt.%Sr,respectively into the Mg-5 Sn-1 Si magnesium alloy,Mg_(24)Y_(5),Mg_(3) Bi_(2),Mg_(3) Sb_(2) and Mg_(2) Sr phases are precipitated *** elements can refineα-Mg grain and Chinese scriptshaped Mg_(2) Si *** efficiency of different trace elements onα-Mg grain and Mg_(2) Si phase is *** element has the best refinement effect,followed by Sb and Bi,while Y has the least refinement ***-5 Sn-1 Si-0.9 Sr alloy has higher tensile properties than the other three modified *** refinement mechanism of Y,Bi and Sr elements on Mg-5 Sn-1 Si magnesium alloy can be explained by the growth restriction factors and the solute *** Mg-5 Sn-1 Si-0.9 Sb alloy,the heterogeneous nuclei of Mg_(3) Sb_(2) phase is the main reason for the refinement of grains and second phases.

关键词： magnesium alloy Mg-5Sn-1Si alloy Y Bi Sb Sr Mg2Si phase

Electromagnetic and microwave absorption properties of Er-Ho-Fe alloys

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Journal of Rare Earths 2018年第7期36卷 715-720页

作者： Jialiang Luo Shunkang Pan Lichun Cheng Peihao Lin yu he Junqing Chang School of Materials Science and Engineering Guilin University of Electronic Technology Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology School of Materials Science and Engineering Central South University

The ErxHo（2-x）Fe（17）（x = 0.0, 0.1,0.2, 0.3, 0.4） powders were prepared by arc melting and high energy ball milling method. The influence of the Er substitution on phase structure, morphology, saturation magnetization,electromagnetic parameters was investigated by X-ray diffraction（XRD）,scanning electron microscopy（SEM）, vibrating sample magnetometer（VSM） and vector network analyzer（VNA）,respectively. The results show that the saturation magnetization increases and the average particle size increases with the increase of Er content. The minimum absorption peak frequency shifts towards a lower frequency region with the increase of Er content. The ErxHo2-xFe17 powder can achieve the minimum RL of-24.07 dB at 6.96 GHz with a thickness of 2.0 mm and the minimum RL is less than-20 dB at the thickness range from 2.0 to 3.0 mm. The minimum RL of ErxHo2-xFe17 is-37.26 dB at5.68 GHz and the frequency bandwidth of R〈-10 dB reaches about 1.2 GHz with a thickness of 2.4 *** the microwave absorbing properties of the composite with different weight ratios of Er0.3Ho1.7Fe17/graphene were researched. The microwave absorbing peaks of the composite shift to lower frequency with the increase of graphene content. The values of the minimum RL of ErxHo2-xFe17/graphene are close to-10 dB with absorbing coating thicknesses increased.

关键词： ErxHo2-xFe17 alloys Reflection loss Electromagnetic parameters Magnetic properties Microwave absorbing properties Rare earths

Electronic structures and properties of pure vanadium

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中国有色金属学会会刊：英文版 1999年第3期9卷 446-450页

作者： he yu(贺昱) Xie Youqing(谢佑卿) Peng Kun(彭坤) Liu Xinbi(刘心笔) Cent S Univ Technol Dept Mat Sci & Engn Changsha 41083 Peoples R China

By the one atom theory the electronic structure of bcc V has been determined to be [Ar](3d n) 1.799 8 (3d c) 2.657 8 (4S c) 0.171 1 (4s f) 0.371 3 . According to this electronic structure of bcc V, its potential curve, cohesive energy, lattice parameter, elasticity and linear thermal expansion coefficient were calculated. The electronic structures of the primary state crystals of fcc V, hcp V and the primary state liquid—V have also been studied.

关键词： vanadium electronic structure physical properties

Porous S-doped carbon nitride foam with accelerated charge dynamics for synchronous photocatalytic hydrogen production and highly selective oxidation of amines

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Nano Research 2024年第8期17卷 6860-6869页

作者： yu he Aiping Wu Nan Wang Ying Xie Chungui Tian Honggang Fu Key Laboratory of Functional Inorganic Material Chemistry(Ministry of Education of the People’s Republic of China) Heilongjiang UniversityHarbin 150080China

Photocatalytic hydrogen evolution coupled with organic oxidation holds great promise for converting solar energy into high-valueadded chemicals,but it is hampered by sluggish charge dynamics and limited redox ***,a porous S-doped carbon nitride(S-C_(3)N_(4−y))foam assembled from ultrathin nanosheets with rich nitrogen vacancies was synthesized using a molecular selfassembly *** S dopants and N vacancies synergistically adjusted the band structure,facilitating light absorption and enhancing the oxidation ***,the ultrathin nanosheets and porous structure provided more exposed active sites and facilitated mass and charge ***,S-C_(3)N_(4−y) foam exhibited enhanced photocatalytic activities for synchronous hydrogen evolution(4960μmol/(h·g))and benzylamine oxidation to N-benzylidenebenzylamine(4885μmol/(h·g))with high selectivity of>99%,which were approximately 17.6 and 72.9 times higher than those of bulk CN,*** photocatalytic coupling pairing reaction promotes the water splitting by consuming H2O2,thereby improving the hydrogen evolution efficiency and achieving the production of high value-added *** study provides an effective route for regulating the morphology and band structure of carbon nitride for synthesizing highly valuable chemicals.

关键词： photocatalysis S-doped carbon nitride band structure regulation hydrogen evolution coupled with benzylamine oxidation reaction mechanism

On-surface photo-induced dechlorination

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Chinese Chemical Letters 2024年第9期35卷 198-201页

作者： yu he Hao Jiang Shaoxuan yuan Jiayi Lu Qiang Sun Materials Genome Institute Shanghai UniversityShanghai 200444China

On-surface Ullmann-type reaction,or the dehalogenated coupling,is arguably the most pivotal reaction in on-surface synthesis for the fabrications of carbon ***,the vast majority of works rely on activating the C-Br bond of aryl bromide which has a moderate bond dissociation *** C-Cl bond of aryl chloride has a higher dissociation energy and requires much higher thermal energy to break the *** this study,we have explored the on-surface photo-induced dechlorination and achieved the activation of three distinct aryl chlorines on the Au(111)surface with mild *** work enriches our understanding of on-surface photo-induced reactions and highlights the potential of photochemistry in realizing unconventional reactions.

关键词： On-surface synthesis Scanning probe microscopy On-surface photochemistry Dechlorination reaction

A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： Huan yuan San-Yi yuan Jie Wu Wen-Jing Sang yu-he Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

Evolution from Sequential Decay to Simultaneous Multifragmentation with Increasing Beam Energy

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Chinese Physics Letters 1996年第3期13卷 168-171页

作者： he Zhi-yong JIN Gen-ming LI Zu-yu DUAN Li-min DAI Guang-xi ZHANG Bao-guo WU he-yu WEN Wan-xin LUO Qing-zheng QI yu-jin Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000

Two-fragment correlation functions have been measured for ^(40)Ar+^(197)Au collisions at E/A=25 *** on the three-body trajectory calculation,a mean emission time of T~450 fm/c for light fragments was extracted from th... 详细信息

关键词： functions. energy. decay

Differential Proteomic Analysis of Carbon Ion Radiation in Sheep Sperm

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Journal of Integrative Agriculture 2013年第9期12卷 1629-1637页

作者： he yu-xuan LI Hong-yan ZHANG Yong he Jian-hua ZHANG Hong ZHAO Xing-xu College of Veterinary Medicine Gansu Agricultural University Department of Medical Physics Institute of Modern PhysicsChinese Academy of Sciences Key Laboratory of heavy Ion Radiation Medicine Chinese Academy of Sciences Key Laboratory of heavy Ion Radiation Medicine of Gansu Province University of Chinese Academy of Sciences Lanzhou Agricultural Science and Technology Research Promotion Center

This study is first to investigate proteomic changes in sheep sperm induced by carbon ion radiation using two-dimensional electrophoresis （2-DE） analysis in the project of breeding a new variety of sheep. Differential expression proteins were detected using the PDQuest 8.0 software after staining with Coomassie blue. Valid spots were then analyzed through liquid chromatography tandem mass spectrometry （LC-MS/MS）. Among the 480 total protein spots displayed in 2-D gels, 6 specific protein spots were observed in sperm gels. A search against protein sequences in the National Center for Biotechnology Information databases （NCBI） indicated that differentially expressed proteins correspond to two proteins, identified to be enolase and transcription factor AP-2-alpha （TFAP-2c0. The two proteins were up-regulated in the irradiated sperm. To the best of our knowledge, this study is the first to identify proteomic changes induced by carbon ion radiation in sheep sperm. The analysis of differential expression protein may be useful in identifying new breeding markers in sheep reproduction and in clarifying the mechanisms involved in irradiation or space breeding.

关键词： sheep sperm protein two-dimensional polyacrylamide gel electrophoresis analysis proteome carbon ionradiation irradiation breeding

Association between PPARG genetic polymorphisms and ischemic stroke risk in a northern Chinese Han population: a case-control study

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Neural Regeneration Research 2019年第11期14卷 1986-1993页

作者： Yan-Zhe Wang he-yu Zhang Fang Liu Lei Li Shu-Min Deng Zhi-Yi he Department of Neurology the First Hospital of China Medical University

Two common polymorphisms of the peroxisome proliferator-activated receptor gamma(PPARG) gene, rs1801282 and rs3856806, may be important candidate gene loci affecting the susceptibility to ischemic stroke. This case-control study sought to identify the relationship between these two single-nucleotide polymorphisms and ischemic stroke risk in a northern Chinese Han population. A total of 910 ischemic stroke participants were recruited from the First Hospital of China Medical University, Shenyang, China as a case group, of whom 895 completed the study. The 883 healthy controls were recruited from the health Check Center of the First Hospital of China Medical University, Shenyang, China. All participants or family members provided informed consent. The study protocol was approved by the Ethics Committee of the First Hospital of China Medical University, China on February 20, 2012(approval No. 2012-38-1). The protocol was registered with the Chinese Clinical Trial Registry(registration number: ChiCTR-COC-17013559). Plasma genomic DNA was extracted from all participants and analyzed for rs1801282 and rs3856806 single nucleotide polymorphisms using a SNaPshot Multiplex sequencing assay. Odds ratios(ORs) and 95% confidence intervals(CIs) were calculated using unconditional logistic regression to estimate the association between ischemic stroke and a particular genotype. Results demonstrated that the G allele frequency of the PPARG gene rs1801282 locus was significantly higher in the case group than in the control group(P he G allele had a 1.844 fold increased risk of ischemic stroke(OR = 1.844, 95% CI: 1.286–2.645, P he rs3856806 T allele had a 1.366 fold increased risk of ischemic stroke(OR = 1.366, 95% CI: 1.077–1.733, P = 0.010). The distribution frequencies of the PPARG gene haplotypes rs1801282-rs3856806 in the control and case groups were determined. The frequency of distribution in the G-T haplotype case

关键词： nerve regeneration stroke cerebral ischemia ischemic stroke peroxisome proliferator-activated receptor γ single-nucleotide polymorphism haplotype analysis interaction case-control study Chinese Han population neural regeneration

Oxidation behavior of Al0.2CoCrFeNi high-entropy alloy film in supercritical water environment

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Rare Metals 2022年第4期41卷 1217-1222页

作者： Bao-Hong Zhu Hao-Chen Qiu Wei Jiang Qing-he yu GRIMAT Engineering Institute Co. LtdBeijing 101407China General Research Institute for Nonferrous Metals Beijing 100088China National Engineering Research Center of Nonferrous Metals Materials and Products for New Energy GRINM Group Co.Ltd.Beijing 100088China

The corrosion resistance of Al0.2CoCrFeNi high-entropy alloy(heA) film deposited by magnetron sputtering was investigated and compared with that of Al0.2 CoCrFeNi heA bulk and G115 *** heA film is composed of face-centered cubic with nanoscale grain *** he As(film and bulk) exhibit higher electro-chemical corrosion resistance than the G115 alloy in 3.5 wt% NaCl solution.

关键词： alloy corrosion resistance