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Effects of Strain Rate on the Mechanic Performance of Lattice Materials

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Journal of Wuhan University of Technology(Materials Science) 2021年第3期36卷 416-423页

作者：牛海燕 YOU Ning MIAO Cheng MU Xiaoming 杨子臻 LU Ruijiao lai Xin LI Guofei Beijing Special Vehicle Research Institute Beijing100072China 32178 Beijing100012China Science and Technology on Materials in Impact Environment Laboratory Yantai264003China Department of Engineering Structure and Mechanics Wuhan University of TechnologyWuhan430070China

Split Hopkinson pressure bar(SHPB)was utilized to explore the effects of loading strain rate on the dynamic compressing strength of the titanium alloy lattice material.Results reveal that the yield strength of alloy lattice material reaches 342 MPa initially and then drops to 200 MPa before it rebounds to 252 MPa while the loading strain rate correspondingly increases from the static value 1401/s to 2084/s.Numerical simulations were then carried out to explore the possible reason underlying.Results show that the lattice structure changed the stress distribution and caused significate stress concentration at finite strain with high strain rate.It is believed that the strain rate strengthening effect and layer-wise failure mode are the main reasons of the above mechanical properties change.

关键词： titanium alloy lattice material dynamic properties

基于博弈论偏序集的煤矿瓦斯爆炸风险评价模型研究

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运筹与管理 2023年第9期32卷 136-142页

作者：赖文哲邵良杉辽宁工程技术大学工商管理学院辽宁葫芦岛125105 辽宁工程技术大学系统工程研究所辽宁葫芦岛125105

准确评价煤矿瓦斯爆炸风险是预防与控制瓦斯爆炸事故的重要前提。基于偏序集理论,提出瓦斯爆炸风险的博弈论偏序集评价模型。依据分级准则划分风险安全等级,对影响瓦斯爆炸风险因素进行综合分析,最终选取通风设施设备、瓦斯涌出量、风... 详细信息

准确评价煤矿瓦斯爆炸风险是预防与控制瓦斯爆炸事故的重要前提。基于偏序集理论,提出瓦斯爆炸风险的博弈论偏序集评价模型。依据分级准则划分风险安全等级,对影响瓦斯爆炸风险因素进行综合分析,最终选取通风设施设备、瓦斯涌出量、风量供需比、安全教育与培训等14项指标(记为y_(1)-y_(14))构成模型的指标集合并进行博弈论优化。运用该模型对20个矿井样本(记为A1-A20)进行风险等级评价,结果表明:模型评价结果的Hasse图表达较为准确。偏序集模型中的各指标权重ω经博弈论法优化后均处于平衡状态,保证了偏序关系的转化,充分发挥出偏序集评价模型中若指标权重次序固定评价结果稳健这一特性。为煤矿瓦斯爆炸风险的评价提供了一种新思路。

关键词：风险评价瓦斯爆炸偏序集博弈论法 Hasse图

高铁网络、高端服务业集聚与区域创新——基于中国地级城市层面的经验证据

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贵州师范大学学报（社会科学版） 2022年第3期 97-106页

作者：许冰来逢波山东交通学院经济与管理学院山东济南250357

本文将高铁开通视作一个准自然实验,基于2004—2016年中国285个地级及以上城市的面板数据,采用多期DID模型实证检验了高铁网络建设对区域创新的影响及作用机制。研究结果表明:(1)高铁网络显著提升了区域创新水平,西部地区与各区域小城... 详细信息

本文将高铁开通视作一个准自然实验,基于2004—2016年中国285个地级及以上城市的面板数据,采用多期DID模型实证检验了高铁网络建设对区域创新的影响及作用机制。研究结果表明:(1)高铁网络显著提升了区域创新水平,西部地区与各区域小城市的创新促进效应受高铁开通的影响更大;(2)在经过PSM-DID方法与剔除特殊样本等稳健性检验后该研究结论仍然成立;(3)中介效应检验表明,高端服务业多样化集聚是高铁网络影响区域创新的重要传导渠道,高铁带来的高端服务业多样化集聚有利于促进区域创新;高铁网络对高端服务业专业化集聚没有显著影响,也不能通过高端服务业专业化集聚促进区域创新。

关键词：高铁网络高端服务业区域创新多期DID模型

A NEW APPROACH TO TRANSMISSION SYSTEM PROTECTION WITH FRULT GENERATED NOISE

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电力系统及其自动化学报 1993年第1期5卷 1-9页

作者： L.L.lai City University UK

The use of non-power frequency components for protection measurements in an area that has received relatively little attention. Although work on the use of switched stack tuners has been reported for fault detection, the sensitivity of switched arrangements is limited by scnsitivity of directional detectors for switching purposes. This paper presents an alternative non-switching scheme which is relatively simple.A simplified typical 400kV system with the line trap, stack tuner, coupling capacitor and bus capacitance to earth is considered. Fault studies by using the EMTP have been carried out, frequency-dependent pararnctcrs are used for the line representation. Arcing faults have also bccn investigated and the results show a great promise of the scheme.

关键词： Fault generated noise transmission system protection.

Waterborne Arsenic Poisoning Caused by Discarded Slags--Yongzhou City,Hunan Province,China,2018

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China CDC weekly 2020年第32期2卷 619-621页

作者： Junjia Lu Yan lai Shaofeng Jiang Peibin Ma Lei Huang Yimei Yang Fangkun Tang Chuntao Huang Lun Hong Yu Yin Chengye Sun National Institute of Occupational Health and Poison Control Chinese Center for Disease Control and PreventionBeijingChina Hunan Prevention and Treatment Institute for Occupational Diseases Changsha CityHunan ProvinceChina

What is already known about this topic?Overexposure to arsenic is toxic and affects bodily systems.In severe cases,loss of motor function and death can occur.What is added by this report?At the end of 2018,a waterborne acute arsenic poisoning event occurred in Yongzhou City of Hunan Province because arsenic-containing slags contaminated the water supply,which resulted in 10 people being poisoned.Patients were poisoned through domestic use of contaminated well water excluding drinking.What are the implications for public health practice?Clinicians should be trained to correctly and promptly identify and diagnose acute arsenic poisoning.The arsenic slags and byproducts should be strictly managed by corresponding enterprises to avoid similar poisoning incidents.When dealing with such events,water intended for domestic use should be closely monitored and environmental pollution should be assessed and controlled.

关键词： Hunan dealing prompt

Exposure to PM2.5 Enhances the PI3K/AKT Signaling and Malignancy of ERα Expression-dependent Non-small Cell Lung Carcinoma

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Biomedical and Environmental Sciences 2021年第4期34卷 319-323页

作者： TIAN Lei LI Ying LIU Huan Liang lai Wen Qing SHI Yue LIU Xiao Hua XI Zhu Ge LIN Ben Cheng Tianjin Institute of Environmental and Operational Medicine Tianjin 300050China The Third Surgical Department of Breast Cancer Tianjin Medical University Cancer Institute and HospitalTianjin 300070China

Atmospheric particulate matter(PM)2.5 is a major carcinogen and is associated with an increased risk of developing various cancers and pulmonary fibrous diseases[1-2].Non-small cell lung cancer(NSCLC)is the major type of lung cancer with high morbidity and mortality rates.Epidemiological studies report that the incidence of NSCLC,particularly adenocarcinoma,significantly differs with the gender[3].Female patients with NSCLC have unique epidemiologic characteristics,imaging profiles,clinical manifestations,and pathological characteristics[4].

关键词： PI3K/AKT NSCLC ERα

深化基础考查突出思维品质--2022年高考全国理综甲卷第18题试题评析与教学启示

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物理教学 2022年第9期44卷 60-62页

作者：赖世锵广东仲元中学广东511400

本文以2022年全国理综甲卷物理试题为例,分析物理试题命题改革的方向与思路,在高中物理教学中,教师应该深化基础性,设置进阶点,加强学生对物理本质的理解,注重物理方法的培养,把教材内容讲全讲透,提升课堂效果,形成学生必备知识与关键能... 详细信息

本文以2022年全国理综甲卷物理试题为例,分析物理试题命题改革的方向与思路,在高中物理教学中,教师应该深化基础性,设置进阶点,加强学生对物理本质的理解,注重物理方法的培养,把教材内容讲全讲透,提升课堂效果,形成学生必备知识与关键能力,提高学生的物理观念与科学思维的核心素养。

关键词：电场磁场带电粒子物理方法必备知识关键能力

Understanding Sulfur Redox Mechanisms in Different Electrolytes for Room-Temperature Na-S Batteries

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Nano-Micro Letters 2021年第8期13卷 107-120页

作者： Hanwen Liu Wei-Hong lai Qiuran Yang Yaojie Lei Can Wu Nana Wang Yun-Xiao Wang Shu-Lei Chou Hua Kun Liu Shi Xue Dou Institute for Superconducting and Electronic Materials Australian Institute of Innovative MaterialsUniversity of WollongongInnovation CampusSquires WayNorth WollongongNSW 2500Australia

This work reports influence of two different electrolytes,carbonate ester and ether electrolytes,on the sulfur redox reactions in room-temperature Na-S batteries.Two sulfur cathodes with different S loading ratio and status are investigated.A sulfur-rich composite with most sulfur dispersed on the surface of a carbon host can realize a high loading ratio(72%S).In contrast,a confined sulfur sample can encapsulate S into the pores of the carbon host with a low loading ratio(44%S).In carbonate ester electrolyte,only the sulfur trapped in porous structures is active via‘solid-solid’behavior during cycling.The S cathode with high surface sulfur shows poor reversible capacity because of the severe side reactions between the surface polysulfides and the carbonate ester solvents.To improve the capacity of the sulfur-rich cathode,ether electrolyte with NaNO_(3) additive is explored to realize a‘solid-liquid’sulfur redox process and confine the shuttle effect of the dissolved polysulfides.As a result,the sulfur-rich cathode achieved high reversible capacity(483 mAh g^(−1)),corresponding to a specific energy of 362 Wh kg^(−1) after 200 cycles,shedding light on the use of ether electrolyte for high-loading sulfur cathode.

关键词： Room-temperature sodium-sulfur batteries Carbonate ester electrolyte Ether electrolyte Sulfur cathode Sulfur redox reactions

Focal peliosis hepatis in a colon cancer patient resembling metastatic liver tumor

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World Journal of Gastroenterology 2012年第41期18卷 5999-6002页

作者： Wu-Jun Xiong Li-Juan Hu Yi-Cheng Jian Yi He Wei Zhou Xin-lai Guo Ya-Xin Zheng Departmentof Gastroenterology Shanghai East Hospital Affiliated to TongjiUniversity Shanghai 200120 China Department of Surgery Shanghai East Hospital Affiliated to Tongji University Shanghai200120 China

Peliosis hepatis(PH) is a rare benign condition characterized by the presence of multiple,randomly distributed,blood filled cystic areas of variable size within the liver parenchyma.PH is difficult to recognize and may be mistaken for neoplasm,metastases or multiple abscesses.A 75-year-old female with a previous history of colon cancer was admitted when a liver mass in the right liver lobe was found 11 mo after surgery during the follow-up period.Computed tomography and magnetic resonance imaging scan of the abdomen were performed.The initial possible diagnosis was metastatic hepatocellular carcinoma.The patient underwent excision of the hepatic segment where the nodule was located.The pathological diagnosis of the surgical specimen was PH.PH should be considered in the differential diagnosis of new liver lesions in patients whose clinical settings do not clearly favor metastasization.Clinicians and radiologists must recognize these lesions to minimize the probability of misdiagnosis and inappropriate treatment.

关键词：肝肿瘤转移性紫斑病患者计算机断层扫描大肠癌类似焦距