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Science Bulletin 2019年第5期64卷 293-300页

作者： Cong Wang Xieyu zhou linwei zhou Ning-Hua Tong Zhong-Yi Lu Wei Ji Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices Department of Physics Renmin University of China

Two-dimensional magnets have received increasing attention since Cr_2Ge_2Te_6 and CrI_3 were experimentally exfoliated and measured in 2017. Although layered ferromagnetic metals were demonstrated at room temperature, a layered ferromagnetic semiconductor with high Curie temperature(Tc) is yet to be unveiled. Here, we theoretically predicted a family of high Tcferromagnetic monolayers, namely MnNX and CrCX(X = Cl, Br and I; C = S, Se and Te). Their Tcvalues were predicted from over 100 K to near 500 K with Monte Carlo simulations using an anisotropic Heisenberg model. Eight members among them show semiconducting bandgaps varying from roughly 0.23 to 1.85 eV. These semiconducting monolayers also show extremely large anisotropy, i.e. ～10~1 for effective masses and ～10~2 for carrier mobilities, along the two in-plane lattice directions of these layers. Additional orbital anisotropy leads to a spin-locked linear dichroism, in different from previously known circular and linear dichroisms in layered *** with the mobility anisotropy, it offers a spin-, dichroism-and mobility-anisotropy *** results manifest the potential of this 2D family for both fundamental research and high performance spin-dependent electronic and optoelectronic devices.

关键词： Two-dimentional materials First-principles calculation Strong mobility anisotropy Spin-locked linear dichroism High-temperature ferromagnets Direct bandgap semic on ductor

Quasi-One-Dimensional Free-Electron-Like States Selected by Intermolecular Hydrogen Bonds at the Glycine/Cu(100) Interface

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Chinese Physics Letters 2020年第11期37卷 75-80页

作者： linwei zhou Chen-Guang Wang Zhixin Hu Xianghua Kong Zhong-Yi Lu Hong Guo Wei Ji Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-nano Devices Renmin University of ChinaBeijing 100872China Center for Joint Quantum Studies and Department of Physics Institute of ScienceTianjin UniversityTianjin 300350China Centre for the Physics of Materials and Department of Physics McGill University3600 University StreetMontrealQCH3A 2T8Canada

We carry out ab initio density functional theory calculations to study manipulation of electronic structures of selfassembled molecular nanostructures on metal surfaces by investigating the geometric and electronic properties of glycine molecules on Cu(100).It is shown that a glycine monolayer on Cu(100)forms a two-dimensional hydrogen-bonding network between the carboxyl and amino groups of glycine using a first principles atomistic calculation on the basis of a recently found *** network includes at least two hydrogen-bonding chains oriented roughly perpendicular to each *** molecule–metal electronic hybridization,these two chains selectively hybridized with the two isotropic degenerate Cu(100)surface states,leading to two anisotropic quasi-one-dimensional surface *** occupying these two states can near-freely move from a molecule to its adjacent molecules directly through the intermolecular hydrogen bonds,rather than mediated by the *** results in the experimentally observed anisotropic free-electron-like *** results suggest that hydrogen-bonding chains are likely candidates for charge conductors.

关键词： structure. chains bonding

Band alignment and interlayer hybridization in monolayer organic/WSe_(2) heterojunction

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Nano Research 2022年第2期15卷 1276-1281页

作者： Yanping Guo Linlu Wu Jinghao Deng linwei zhou Wei Jiang Shuangzan Lu Da Huo Jiamin Ji Yusong Bai Xiaoyu Lin Shunping Zhang Hongxing Xu Wei Ji Chendong Zhang Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan UniversityWuhan 430027China Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices Renmin University oj ChinaBeijing 100872China

Semiconducting heterojunctions(HJs),comprised of atomically thin transition metal dichalcogenides(TMDs),have shown great potentials in electronic and optoelectronic ***/TMD hybrid bilayers hold enhanced pumping efficiency of interfacial excitons,tunable electronic structures and optical properties,and other superior advantages to these inorganic ***,we report a direct probe of the interfacial electronic structures of a crystalline monolayer(ML)perylene-3,4,9,10-tetracarboxylic-dianhydride(PTCDA)/ML-WSe_(2) HJ using scanning tunneling microscopy,photoluminescence,and first-principle *** PTCDAAA/Se_(2) interfacial interactions lead to appreciable hybridization of the WSe_(2) conduction band with PTCDA unoccupied states,accompanying with a significant amount of PTCDA-to-WSe_(2) charge transfer(by 0.06 e/PTCDA).A type-ll band alignment was directly determined with a valence band offset of-1.69 eV,and an apparent conduction band offset of-1.57 ***,we found that the local stacking geometry at the HJ interface differentiates the hybridized interfacial states.

关键词： two-dimensional materials organic/transition metal dichalcogenide(TMD)heterojunction interlayer hybridization band diagram

Optimal parameter space for stabilizing the ferroelectric phase of Hf_(0.5)Zr_(0.5)O_(2) thin films under strain and electric fields

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Chinese Physics B 2024年第7期33卷 509-517页

作者：王侣锦王聪周霖蔚周谐宇潘宇浩吴幸季威 Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China In Situ Devices Center School of Integrated CircuitsEast China Normal UniversityShanghai 200241China

Hafnia-based ferroelectric materials, like Hf_(0.5)Zr_(0.5)O_(2)(HZO), have received tremendous attention owing to their potentials for building ultra-thin ferroelectric devices. The orthorhombic(O)-phase of HZO is ferroelectric but metastable in its bulk form under ambient conditions, which poses a considerable challenge to maintaining the operation performance of HZO-based ferroelectric devices. Here, we theoretically addressed this issue that provides parameter spaces for stabilizing the O-phase of HZO thin-films under various conditions. Three mechanisms were found to be capable of lowering the relative energy of the O-phase, namely, more significant surface-bulk portion of(111) surfaces, compressive c-axis strain,and positive electric fields. Considering these mechanisms, we plotted two ternary phase diagrams for HZO thin-films where the strain was applied along the in-plane uniaxial and biaxial, respectively. These diagrams indicate the O-phase could be stabilized by solely shrinking the film-thickness below 12.26 nm, ascribed to its lower surface energies. All these results shed considerable light on designing more robust and higher-performance ferroelectric devices.

关键词： Hf_(0.5)Zr_(0.5)O_(2) orthorhombic phase ferroelectric films phase stability thickness-dependent ternary phase diagrams

Two ultra-stable novel allotropes of tellurium few-layers

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Chinese Physics B 2020年第9期29卷 458-463页

作者： Changlin Yan Cong Wang linwei zhou Pengjie Guo Kai Liu Zhong-Yi Lu Zhihai Cheng Yang Chai Anlian Pan Wei Ji School of Physics and Electronics Hunan UniversityChangsha 410082China Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China The Hong Kong Polytechnic University Hung HomKowloonHong KongChina Key Laboratory for Micro-Nano Physics and Technology of Hunan Province College of Materials Science and EngineeringHunan UniversityChangsha 410082China

At least four two-or quasi-one-dimensional allotropes and a mixture of them were theoretically predicted or experimentally observed for low-dimensional Te,namely theα,β,γ,δ,and chiral-α+δ*** them theγandαphases were found to be the most stable phases for monolayer and thicker layers,***,we found two novel low-dimensional phases,namely theεandζ***ζphase is over 29 meV/Te more stable than the most stable monolayerγphase,and theεphase shows comparable stability with the most stable monolayerγ*** energetic difference between theζandαphases reduces with respect to the increased layer thickness and vanishes at the four-layer(12-sublayer)thickness,while this thickness increases under change ***εandζphases are metallic chains and layers,***ζphase,with very strong interlayer coupling,shows quantum well states in its layer-dependent *** results provide significantly insight into the understanding of polytypism in Te few-layers and may boost tremendous studies on properties of various few-layer phases.

关键词： two-dimensional materials Te density functional theory

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老年人急性上消化道出血病因研究

中华老年医学杂志 2016年第2期35卷 198-200页

作者：周林伟浙江省台州市玉环县坎门街道社区卫生服务中心急诊内科 317602

目的探讨导致老年人急性上消化道出血可能病因。方法收集我院2012年1月至2015年5月370例确诊的急性上消化道出血患者作为目标人群，回顾性分析且按年龄分为老年组和非老年组两组，比较两组患者上消化道出血病因与诱因情况。结果胃溃疡... 详细信息

目的探讨导致老年人急性上消化道出血可能病因。方法收集我院2012年1月至2015年5月370例确诊的急性上消化道出血患者作为目标人群，回顾性分析且按年龄分为老年组和非老年组两组，比较两组患者上消化道出血病因与诱因情况。结果胃溃疡（36．5％和12．3％）与消化道肿瘤（16．4％和2．4％）导致的上消化道出血老年组高于非老年组（χ2=30．149、23．093，均P〈O．01）；急性胃黏膜病变（8．8％和20．4％）、十二指肠溃疡（25．2oA和38．9%）、胃底及食道静脉曲张（1．9％和8．5％）导致的上消化道出血老年组低于非老年组（χ2=9．320、7．706、7．534，均P〈0．01）；静脉曲张因过度服药（18．2％和2．8％）与精神状态（17．0％和2．4％）诱导上消化道出血老年组高于非老年组（χ2=25．092，24．502，均P〈0．01）。不规律饮食（1．3％和17．5％）、酗酒（2．5％和13．7％）、过劳（2．5%和7．1％）诱导上消化道出血老年组低于非老年组（χ2=25．478、14．070、3．9270，均P〈0．01或0．05）．结论急性上消化道出血的病因较多，老年常见病因为为胃溃疡与消化道肿瘤；过度服药和精神状态是诱发老年患者发生急性消化道出血的主要因素，应加强预防。

关键词：出血胃肠道危险因素

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复合式土压平衡盾构机刀盘开口模式设计

哈尔滨工程大学学报 2017年第3期38卷 433-439页

作者：霍军周周林伟朱冬张伟王伟政孙伟大连理工大学机械工程学院辽宁大连116024

复合式土压平衡盾构机在掘进过程中,刀盘开口模式直接影响碴土流动性,碴土流动性能够保证施工开挖面压力平衡,因此合理的刀盘开口模式是保证盾构系统内部压力稳定和掘进安全的关键。本文针对加入改性材料后具有一定流动特性的碴土,运用... 详细信息

复合式土压平衡盾构机在掘进过程中,刀盘开口模式直接影响碴土流动性,碴土流动性能够保证施工开挖面压力平衡,因此合理的刀盘开口模式是保证盾构系统内部压力稳定和掘进安全的关键。本文针对加入改性材料后具有一定流动特性的碴土,运用计算流体力学的方法,研究了不同刀盘开口方式对碴土流动性的影响。分别对比了相同和不同开口率下,对于同一性质的流体,盾构系统的压力传递情况,得到了系统轴向的压力分布规律。针对不同开口率得到了开口率大小与压力传递的关系,针对相同开口率得到了不同开口位置与压力传递的关系,为刀盘开口模式的结构设计提供依据。

关键词：复合式土压平衡盾构机拓扑结构开口率压力传递计算流体力学盾构机

基于风洞试验的不同坡度多跨锯齿屋面风压特性研究

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实验力学 2021年第2期36卷 259-268页

作者：李春光周林威韩艳陈甦人长沙理工大学土木工程学院湖南长沙410014

多跨锯齿屋面因其具有跨度大、结构轻盈的特点成为典型的风灾易损结构。目前国内规范对锯齿屋盖的风荷载规定较为粗略,简单给定了统一的风压系数参考值,在实际工程应用中具有一定的局限性。本文以某4跨锯齿房屋为研究对象,通过风洞试验... 详细信息

多跨锯齿屋面因其具有跨度大、结构轻盈的特点成为典型的风灾易损结构。目前国内规范对锯齿屋盖的风荷载规定较为粗略,简单给定了统一的风压系数参考值,在实际工程应用中具有一定的局限性。本文以某4跨锯齿房屋为研究对象,通过风洞试验测试了15°、21°、26°、30°和40°等5种不同屋面坡度对锯齿屋盖风压特性的影响。试验结果表明,我国建筑结构荷载规范GB 50009-2012关于锯齿屋面的负风压系数绝对值明显偏小,锯齿屋面最不利均面积负风压系数随着坡度的增加逐渐从高屋角(HC)区转移到屋面边区(SE),且与HC区相反,SE区内的最不利负风压系数绝对值随角度增加而增大;锯齿中间B、C跨最不利均面积负风压系数始终出现在HE区,其绝对值随角度增加而增大,而尾跨D则出现在SE区,且随角度增加而减小;屋面最不利极值负风压系数为-9.6,随着屋面坡度的增大,屋面的最大极值负风压系数绝对值逐渐减小。此外,以各坡度屋面负风压系数的分布为依据,给出了不同屋面坡度范围和不同跨屋面风压系数分区划分建议。

关键词：风洞试验锯齿屋面风压系数分区划分

基于灰色层次理论液压机构断路器运行状态的综合评价

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山西电力 2016年第1期 39-42页

作者：周林伟程刚国网山西省电力公司晋城供电公司山西晋城048000

提出了一种液压操作机构断路器运行状态的灰色层次理论综合评价方法。根据液压操作机构断路器构成元件,定义了5种指标集,用灰色关联分析法计算各元件的关联系数,用层次分析法确定权重系数,最后采用关联度大小进行综合评价分析,并对实际... 详细信息

提出了一种液压操作机构断路器运行状态的灰色层次理论综合评价方法。根据液压操作机构断路器构成元件,定义了5种指标集,用灰色关联分析法计算各元件的关联系数,用层次分析法确定权重系数,最后采用关联度大小进行综合评价分析,并对实际液压操作机构断路器进行计算,取得了良好的计算结果。

关键词：液压机构断路器关联度综合评价运行状态灰色层次分析法

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中老年尘肺病患者心理健康状况及影响因素

中华行为医学与脑科学杂志 2024年第4期33卷 352-356页

作者：连俊秀张红鑫林铭淳周子琦周林玮郭兴端林立山东第二医科大学公共卫生学院潍坊261053 济宁医学院职业卫生与环境医学重点实验室济宁272013

目的:探讨中老年尘肺病患者心理健康状况及其影响因素。方法:选取2023年3月—5月在某职业病医院住院的尘肺病患者120例(Ⅰ期85例,Ⅱ期19例,Ⅲ期16例)为尘肺组,同期选取某医院128名健康查体人员为对照组。对尘肺组患者进行肺功能测定,包... 详细信息

目的:探讨中老年尘肺病患者心理健康状况及其影响因素。方法:选取2023年3月—5月在某职业病医院住院的尘肺病患者120例(Ⅰ期85例,Ⅱ期19例,Ⅲ期16例)为尘肺组,同期选取某医院128名健康查体人员为对照组。对尘肺组患者进行肺功能测定,包括用力肺活量(forced vital capacity,FVC)、第一秒用力呼气容积(forced expiratory volume in one second,FEV1)、FEV1/FVC、呼气峰值流量(peak expiratory flow,PEF)、一氧化碳弥散量(diffusing capacity of the lungs for carbon monoxide,DLCO),同时采用症状自评量表(symptom checklist-90,SCL-90)对两组被试分别进行心理健康评估。采用SPSS 22.0对数据进行方差分析、Kruskal-Wallis检验、Spearman相关分析、Logistic回归分析。结果:Ⅲ期尘肺病患者肺功能指标FVC[(83.84±15.11)L]、FEV1[(75.72±18.24)L]、FEV1/FVC[(71.43±11.84)%]、PEF[(73.94±23.33)L/S]、DLCO[(72.60±23.91)mmol·min^(-1)·kPa^(-1)]均低于Ⅰ期尘肺患者[(94.99±16.52)L,(93.48±19.55)L,(77.32±7.64)%,(99.28±26.80)L/s,(95.93±22.93)mmol·min^(-1)·kPa^(-1)],均差异有统计学意义(均P<0.05)。尘肺组SCL-90总分及各因子评分均明显均高于对照组(均P<0.05)。SCL-90总分与受教育程度(r=-0.246,P=0.007)、FEV1(r=-0.252,P=0.047)、FEV1/FVC(r=-0.260,P=0.042)呈负相关,与分期(r=0.184,P=0.045)、饮酒(r=0.198,P=0.030)呈正相关。回归分析结果显示,分期高是心理健康水平下降的危险因素,较高的文化程度以及较好的肺功能是心理健康水平下降的保护因素(均P<0.05)。结论:尘肺病患者易出现心理问题,其中以躯体化、强迫症状、抑郁和焦虑等较常见。受教育程度、肺功能、尘肺分期会对尘肺病患者的心理健康造成影响。

关键词：尘肺病心理健康影响因素中年人老年人