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Study on theoretical model for electrical explosion resistivity of Al/ni reactive multilayer foil

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Defence Technology（防务技术） 2024年第2期32卷 348-356页

作者： zehao Wang Tao Wang Pengfei Xue Mingyu Li Qingxuan Zeng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China China Ship Development and Design Center Wuhan 430064China

Al/ni reactive multilayer foil(RMF)possesses excellent comprehensive properties as a promising substitute for traditional Cu bridge.A theoretical resistivity model of Al/ni RMF was developed to guide the optimization of ***/ni RMF with different bilayer thicknesses and bridge dimensions were prepared by MEMS technology and electrical explosion tests were carried *** to physical and chemical reactions in bridge,the electrical explosion process was divided into 5 stages:heating of condensed bridge,vaporization and diffusion of Al layers,intermetallic combination reaction,intrinsic explosion,ionization of metal gases,which are obviously shown in measured voltage *** of interface and grain boundary scattering on the resistivity of film metal were *** on variations of substance and state,the resistivity was developed as a function of temperature at each *** explosion curves were calculated by this model at different bilayer thicknesses,bridge dimensions and capacitor voltages,which showed an excellent agreement with experimental ones.

关键词： Al/ni reactive multilayer foil Electrical explosion Resistivity model Phase transition Calculation

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铁路职工心理健康状况调查研究

郑州铁路职业技术学院学报 2023年第1期35卷 102-105页

作者：倪泽昊郑州铁路职业技术学院河南郑州451460

90项症状自评量表(SCL-90)是已标准化了的症状自评量表,可以评价一个人的思维、情感、人际关系、生活习惯等心理健康要素,具有良好的效果。借助SCL-90对某铁路局职工进行抽样调查,结果显示:铁路职工整体心理健康水平相较于全国常模偏低... 详细信息

90项症状自评量表(SCL-90)是已标准化了的症状自评量表,可以评价一个人的思维、情感、人际关系、生活习惯等心理健康要素,具有良好的效果。借助SCL-90对某铁路局职工进行抽样调查,结果显示:铁路职工整体心理健康水平相较于全国常模偏低;铁路局轮班、日勤、管理三个不同工种员工之间,轮班岗的员工更容易出现心理问题;运动有利于铁路职工的心理健康,且每周3-5次最佳。

关键词：铁路职工 SCL-90 心理健康

20Cr32ni1Nb高温合金焊接接头组织及力学性能研究

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电焊机 2024年第4期54卷 141-147页

作者：张泽浩肖明颖烟台玛努尔高温合金有限公司山东烟台264034 烟台哈尔滨工程大学研究院山东烟台264006

采用高镍和低镍两种焊丝氩弧焊接20Cr32ni1Nb铸造耐热合金炉管,旨在研究20Cr32ni1Nb高温合金焊接接头的组织和力学性能。通过金相、硬度和拉伸等表征测试方法对比分析两种焊接接头的显微组织和力学性能。结果表明,焊接接头的母材由柱状... 详细信息

采用高镍和低镍两种焊丝氩弧焊接20Cr32ni1Nb铸造耐热合金炉管,旨在研究20Cr32ni1Nb高温合金焊接接头的组织和力学性能。通过金相、硬度和拉伸等表征测试方法对比分析两种焊接接头的显微组织和力学性能。结果表明,焊接接头的母材由柱状奥氏体晶粒和网状晶界构成,焊缝是由细小的针状或者柱状奥氏体晶粒和沿晶界分布的链状或者块状碳化物构成。受焊接热输入影响,热影响区的母材晶粒粗化,并在晶界处析出二次碳化物;焊接接头热影响区的显微硬度较母材下降约20 HV_(0.2);低镍焊缝的显微硬度略低于高镍焊缝,更接近于母材,约为220 HV_(0.2),这有利于改善焊接接头的整体力学性能。两种焊接接头拉伸性能均满足焊接评定要求,其短时拉伸力学性能相近,但低镍焊接接头的高温拉伸持久时间远超高镍焊接接头,达3.9倍,这是因为低镍焊缝更易析出碳化物,阻碍晶界滑移和位错聚集,进而提高其抗蠕变性能。低镍焊丝更适合20Cr32ni1Nb合金的焊接。

关键词：高温合金焊接接头焊材成分显微组织力学性能

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Practical strategy to construct anti-osteosarcoma bone substitutes by loading cisplatin into 3D-printed titanium alloy implants using a thermosensitive hydrogel

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Bioactive Materials 2021年第12期6卷 4542-4557页

作者： zehao Jing Renhua ni Jiedong Wang Xinhong Lin Daoyang Fan Qingguang Wei Teng Zhang Yufeng Zheng Hong Cai Zhongjun Liu Department of Orthopedics Peking University Third HospitalBeijing100191People’s Republic of China Engineering Research Center of Bone and Joint Precision Medicine Ministry of EducationBeijing100191People’s Republic of China Beijing Key Laboratory of Spinal Disease Research Beijing100191People’s Republic of China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871People’s Republic of China

Surgical resection and perioperative adjuvant chemotherapy-based therapies have improved the prognosis of patients with osteosarcoma;however,intraoperative bone defects,local tumour recurrence,and chemotherapy-induced adverse effects still affect the quality of life of *** 3D-printed titanium alloy(Ti6Al4V)implants have advantages over traditional implants in bone repair,including lower elastic modulus,lower stiffness,better bone conduction,more bone in-growth,stronger mechanical interlocking,and lager drug-loading capacity by their inherent porous ***,cisplatin,a clinical first-line anti-osteosarcoma drug,was loaded into Ti6Al4V implants,within a PLGA-PEG-PLGA thermo-sensitive hydrogel,to construct bone substitutes with both anti-osteosarcoma and bone-repair *** optimal concentrations of cisplatin(0.8 and 1.6 mg/mL)were first determined in ***,the anti-tumour effect and biosafety of the cisplatin/hydrogel-loaded implants,as well as their bone-repair potential were evaluated in vivo in tumour-bearing mouse,and bone defect rabbit models,*** loading of cisplatin reduced tumour volume by more than two-thirds(from 641.1 to 201.4 mm3)with negligible organ damage,achieving better anti-tumour effects while avoiding the adverse effects of systemic cisplatin *** bone repair was hindered by cisplatin loading at 4 weeks,no difference was observed at 8 weeks in the context of implants with versus without cisplatin,indicating acceptable long-term stability of all implants(with 8.48%-10.04%bone in-growth and 16.94%-20.53%osseointegration).Overall,cisplatin/hydrogel-loaded 3D-printed Ti6Al4V implants are safe and effective for treating osteosarcoma-caused bone defects,and should be considered for clinical use.

关键词： 3D-printed titanium alloy Orthopaedic implant Osteosarcoma Hydrogel Local chemotherapy

Study on theoretical model for electrical explosion resistivity of Al/ni reactive multilayer foil

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企业数字化与全要素生产率提升——来自中国上市公司的证据

Defence technology 2024年第2期

作者： zehao Wang Tao Wang Pengfei Xue Mingyu Li Qingxuan Zeng

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贵州财经大学学报 2023年第5期 41-51页

作者：巫景飞王泽昊倪中新上海大学上海200444

数字化已成为当下企业最重要的战略,但数字化能否提升企业全要素生产率尚存争议。基于上市公司及其一级控股子公司与数字化相关的无形资产投入、专利、软件著作权数量和年报词频等数据,构建包含投入、成果、关注度三维度的数字化水平指... 详细信息

数字化已成为当下企业最重要的战略,但数字化能否提升企业全要素生产率尚存争议。基于上市公司及其一级控股子公司与数字化相关的无形资产投入、专利、软件著作权数量和年报词频等数据,构建包含投入、成果、关注度三维度的数字化水平指标体系,并运用熵值法测度2010~2020年沪深A股上市公司的数字化水平。然后,检验企业数字化对全要素生产率的影响效果与机制。研究发现:中国上市公司总体数字化水平波动上升,呈现国有企业快于非国有企业,东部地区快于中西部地区,信息技术行业快于其他行业;数字化通过提升企业内部沟通效率、增强规模经济效应、降低大客户依赖以及提高供应链管理效率等四项机制促进全要素生产率的提升;对于非国有性质、强竞争行业以及东部地区的企业,数字化对全要素生产率的促进作用更为显著。

关键词：全要素生产率数字化熵值法高质量发展

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曲体束腰型光声池的设计及性能分析

中国激光 2021年第1期48卷 180-189页

作者：李泽昊杨春勇唐梓豪彭苗苗倪文军郭连波侯金陈少平智能无线通信湖北省重点实验室中南民族大学电子信息工程学院湖北武汉430074 南洋理工大学电气电子工程学院新加坡新加坡639798 华中科技大学武汉光电国家研究中心湖北武汉430074

在基于光声光谱技术的痕量气体检测系统中,光声池是决定系统性能的关键部件。针对传统柱形光声池受限于形状优化参数的问题,本文提出并设计了一种母线为双曲线的曲体束腰型光声池方案,该方案创新性地引入了母线离心率参数,实现了三维立... 详细信息

在基于光声光谱技术的痕量气体检测系统中,光声池是决定系统性能的关键部件。针对传统柱形光声池受限于形状优化参数的问题,本文提出并设计了一种母线为双曲线的曲体束腰型光声池方案,该方案创新性地引入了母线离心率参数,实现了三维立体优化。本文基于有限元分析方法,利用COMSOL软件构建模型,分析母线离心率为7.14的光声池结构,得到了该结构在热黏性损耗作用下的前八阶声学模态值以及可视化振型。仿真结果表明,所设计的光声池的品质因数高达83.3;对光声池进行形状优化,发现光声池谐振腔长度对谐振频率敏感,母线短半轴长对声压幅值敏感。通过调节母线离心率可以有效地调节谐振频率且不影响声压幅值。光声池的幅频响应特性表明,较小的离心率易激发多谐振峰,在离心率为5时,激发的第一、第二谐振峰较强,它们的品质因数分别为75.9和128.9。本研究表明,此类曲体束腰型光声池具有优良的性能及较高的可设计度,对新型光声检测技术具备多场景适应能力,具有重要的理论和工程应用价值。

关键词：光谱学光声光谱痕量气体检测有限元方法光声池声学模态值

An updated Vegetation Map of China(1:1000000)

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Science Bulletin 2020年第13期65卷 1125-1136,M0004页

作者： Yanjun Su Qinghua Guo Tianyu Hu Hongcan Guan Shichao Jin Shazhou An Xuelin Chen Ke Guo Zhanqing Hao Yuanman Hu Yongmei Huang Mingxi Jiang Jiaxiang Li Zhenji Li Xiankun Li Xiaowei Li Cunzhu Liang Renlin Liu Qing Liu Hongwei ni Shaolin Peng zehao Shen Zhiyao Tang Xingjun Tian Xihua Wang Renqing Wang Zongqiang Xie Yingzhong Xie Xiaoniu Xu Xiaobo Yang Yongchuan Yang Lifei Yu Ming Yue Feng Zhang Keping Ma State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China College of Pratacultural and Environmental Sciences Xinjiang Agricultural UniversityUrumqi 830052China College of Life Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China College of Resources Science and Technology Beijing Normal UniversityBeijing 100875China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China College of Forestry Central South University of Forestry&TechnologyChangsha 410004China College of Life Sciences Xiamen UniversityXiamen 361005China Guangxi Institute of Botany Chinese Academy of SciencesGuilin 541006China Agricultural College Ningxia UniversityYinchuan 750021China School of Ecology and Environment Inner Mongolia UniversityHohhot 010000China Institute of Navel Orange School of Life and Environmental ScienceGannan Normal UniversityGanzhou 341000China Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Institute of Natural Resources and Ecology Heilongjiang Academy of SciencesHarbin 150040China State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China Institute of Ecology College of Urban and Environmental Science and Key Laboratory of Earth Surface ProcessesPeking UniversityBeijing 100871China School of Life Sciences Nanjing UniversityNanjing 210023China Zhejiang Tiantong Forest Ecosystem National Observation and Research St

Vegetation maps are important sources of information for biodiversity conservation,ecological studies,vegetation management and restoration,and national strategic decision *** current Vegetation Map of China(1:1000000)was generated by a team of more than 250 scientists in an effort that lasted over 20 years starting in the ***,the vegetation distribution of China has experienced drastic changes during the rapid development of China in the last three decades,and it urgently needs to be updated to better represent the distribution of current vegetation ***,we describe the process of updating the Vegetation Map of China(1:1000000)generated in the 1980s using a‘‘crowdsourcing-change detection-classification-expert knowledge"vegetation mapping strategy.A total of 203,024 field samples were collected,and 50 taxonomists were involved in the updating *** resulting updated map has 12 vegetation type groups,55 vegetation types/subtypes,and 866 vegetation formation/sub-formation *** overall accuracy and kappa coefficient of the updated map are 64.8%and 0.52 at the vegetation type group level,61%and 0.55 at the vegetation type/subtype level and 40%and 0.38 at the vegetation formation/sub-formation *** compared to the original map,the updated map showed that 3.3 million km^2 of vegetated areas of China have changed their vegetation type group during the past three decades due to anthropogenic activities and climatic *** expect this updated map to benefit the understanding and management of China’s terrestrial ecosystems.

关键词： Vegetation map Crowdsource Remote sensing Update

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复垦不同年限煤矸山土壤重金属污染状况评价

水土保持研究 2017年第5期24卷 343-346页

作者：亢晨宇贺泽好于亚军山西师范大学地理科学学院山西临汾041000

为研究复垦年限对煤矸山土壤重金属的影响,以山西省霍州市曹村煤矿煤矸山复垦3a,5a,7a和9a农田为研究对象,对复垦地土壤重金属Hg,Cd,Pb,As和ni的质量分数及其污染状况进行了分析。结果表明:(1)煤矸山复垦农田0—20cm和20—40cm土层土壤... 详细信息

为研究复垦年限对煤矸山土壤重金属的影响,以山西省霍州市曹村煤矿煤矸山复垦3a,5a,7a和9a农田为研究对象,对复垦地土壤重金属Hg,Cd,Pb,As和ni的质量分数及其污染状况进行了分析。结果表明:(1)煤矸山复垦农田0—20cm和20—40cm土层土壤重金属质量分数有随复垦年限增加而增加的趋势,其中Pb,Cd表现最明显,而Hg的增加趋势主要出现在20—40cm土层;同时,煤矸山复垦农田土壤重金属质量分数均不同程度地高于当地普通农田,尤其在20—40cm土层表现更明显;(2)单因子污染指数表明,Hg和As在0—20cm和20—40cm土层污染程度随年限没有变化,分别为重度污染和轻微污染,Pb和Cd在0—20cm也没有变化,分别为轻微污染和轻度污染,但在20—40cm土层随年限增长达到轻度污染和中度污染;综合污染指数表明,复垦农田在0—20cm和20—40cm土层污染指数均表现为随复垦年限增加而增加的趋势,4种复垦年限农田均达到重度污染。研究结果有助于指导煤矸山植被恢复和复垦地的合理利用。

关键词：复垦土壤不同年限煤矸山土壤重金属生态风险