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抛丸和抛浆对金属基体表面完整性的影响对比

塑性工程学报 2024年第2期31卷 97-104页

作者：柴泽琳周存龙齐浩郭瑞李春阳太原科技大学机械工程学院山西省冶金设备设计理论与技术重点试验室山西太原030024

以Q235热轧带钢为研究对象,利用ANSYS/AUTODYN模块模拟了抛丸和抛浆对基体表面的冲击过程,并结合抛丸和抛浆冲击试验研究了带钢表面粗糙度和残余应力。结果表明,抛丸冲击后基体表面冲击深度和冲击直径分别比抛浆高20%~49%和9%~22%;抛丸... 详细信息

以Q235热轧带钢为研究对象,利用ANSYS/AUTODYN模块模拟了抛丸和抛浆对基体表面的冲击过程,并结合抛丸和抛浆冲击试验研究了带钢表面粗糙度和残余应力。结果表明,抛丸冲击后基体表面冲击深度和冲击直径分别比抛浆高20%~49%和9%~22%;抛丸冲击基体表面瞬时温度为247~413℃,抛浆冲击基体表面瞬时温度为60~97℃,说明浆体中的流体可以带走大量冲击热能。抛丸冲击后基体表面粗糙度和表面残余应力比抛浆冲击分别高22%~37%和3.7%~13.8%,抛浆冲击后基体表面完整性优于抛丸冲击。

关键词：抛丸抛浆冲击力表面粗糙度残余应力

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Comparison of the Stress Corrosion Cracking Behaviour of AISI 304 Pipes Welded by TIG and LBW

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 579-589页

作者： Ji-Jin Xu Shuai Wang ze chai Chun Yu Jun-Mei Chen Hao Lu Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China

The stress corrosion cracking(SCC)behaviour of AISI 304 pipe girth welds which were welded by a single-pass laser beam welding(LBW)and a multi-pass tungsten inert gas welding(TIG),respectively,was studied by the slow strain rate tests combined with the electrochemical corrosion *** results show that fracture of both the TIG joint and LBW joint occurs in the heat-affected zone(HAZ).According to the electron-backscattered diffraction observation of the micro structures,comparison of potentiodynamic polarization curves and X-ray photoelectron spectroscopy analysis of corrosion products on HAZs of the two joints after the electrochemical tests,the LBW joint exhibits better SCC resistance than the TIG joint in corrosion environments,due to the synthetic effect of more Cr_(2)O_(3) in corrosion products,finer grains,lower residual strain and higher δ-ferrite content in its *** the TIG joint has better mechanical property,considering lower SCC susceptibility and higher production efficiency of the LBW joint,the LBW promisingly replaces the TIG for welding of AISI304 pipes in the nuclear power industry.

关键词： Laser beam welding Slow strain rate test Stress corrosion cracking Tungsten inert gas welding AISI 304 stainless steel

Sensing properties and mechanisms of LaF_(3)-Co_(3)O_(4) nanorods for low-concentration methanol detection

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Rare Metals 2024年第5期43卷 2193-2204页

作者： Xiao-Xi He Hong-Feng chai Yi-Wen Zhou Ke-Wei Liu ze-Xin Yu Chao Zhang College of Mechanical Engineering Yangzhou UniversityYangzhou225127China Institutefor Manufacturing Technologies of Ceramic Components and Composites(IMTCCC) University of Stuttgart70569 StuttgartGermany

Methanol is one of the characteristic gases that distinguish between healthy individuals and lung cancer(LC)lesions in exhaled human *** concentration in exhaled breath is generally below one part per million(1×10^(-6)).The second-phase composite is widely regarded as one of the methods to improve the gas-sensing perfor-mance of metal oxide semiconductor(MOS)*** this study,LaF_(3)-Co_(3)O_(4) was synthesized by a simple hydrothermal method to enhance its low-concentration methanol gas-sensing performance.5 at%LaF_(3)-Co_(3)O_(4) nanorods exhibited excellent methanol detection performance,including a wider linear detection concentration range(0.2×10^(-6)~5×10^(-6)),a response value exceeding 4.0 for 1×10^(-6)methanol at 275°C and 75%relative humidity(RH),long-term stability(maximum deviation within 15%over 2 weeks),and excellent *** mechanism of performance enhancement was studied using various techniques,and density functional *** special spinel structure of Co_(3)O_(4),the high ionic migration of F-in LaF_(3),the larger specific surface area of 5 at%LaF_(3)-Co_(3)O_(4) nanorods,and the generated crystal defects all explain the excellentmethanol gas-sensing *** work provides a novel route to prepare MOS composite materials for low-concentration methanol gas detection.

关键词： Gas sensor LaF_(3) Co_(3)O_(4) Methanol Lung cancer

Preparation of Fe-As alloys by mechanical alloying and vacuum hot-pressed sintering:microstructure evolution,mechanical properties,and mechanisms

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Rare Metals 2024年第8期43卷 3876-3892页

作者： Fei chai Fei-Ping Zhao Zhan Hu Shi-Yi Wen Ben-Hammouda Samia ze-Lin Fu Xin-Ting Lai Yan-Jie Liang Xiao-Bo Min Li-Yuan chai School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Institute of Environmental EngineeringCentral South UniversityChangsha 410083HunanChin State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Building Civiland Environmental EngineeringConcordia UniversityMontreal H3G 1M8Canada

Arsenic materials have attracted great attention due to their unique ***,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low temperature and the high melting point of ***,a new Fe-As alloy was obtained by mechanical alloying(MA) followed by vacuum hot-pressed sintering(VHPS).Moreover,a systematic study was carried out on the microstructural evolution,phase composition,leaching toxicity of As,and physical and mechanical properties of Fe-As alloys with varying weight fractions of As(20%,25%,30%,35%,45%,55%,65%,and 75%).The results showed that pre-alloyed metallic powders(PAMPs) have a fine grain size and specific supersaturated solid solution after MA,which could effectively improve the mechanical properties of Fe-As alloys by VHPS.A high density(> 7.350 g·cm^(-3)),low toxicity,and excellent mechanical properties could be obtained for FeAs alloys sintered via VHPS by adding an appropriate amount of As,which is more valuable than commercial Fe-As *** Fe-25% As alloy with low toxicity and a relatively high density(7.635 g·cm^(-3)) provides an ultra-high compressive strength(1989.19 MPa),while the Fe-65% As alloy owns the maximum Vickers hardness(HVo.5 899.41).After leaching by the toxicity characteristic leaching procedure(TCLP),these alloys could still maintain good mechanical performance,and the strengthening mechanisms of Fe-As alloys before and after leaching were *** in the grain size,micro structure,and phase distribution induced significant differences in the compressive strength and hardness.

关键词： Mechanical alloying Vacuum hot-pressed sintering High-pressure Arsenic-iron alloys Mechanical properties

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对话:教师干预校园欺凌的可能理路

教学与管理 2019年第27期 67-69页

作者：柴泽英华东师范大学教育学部

近年来,校园欺凌成为'世界性'问题。同时,反欺凌也达成了世界共识。从弗莱雷'对话'视角出发,试图链接此视角与校园欺凌干预的契合点,探寻教师如何通过'对话'干预校园欺凌,以期达成促使欺凌者与被欺凌者共同和解的目的。

关键词：校园欺凌欺凌干预对话共同和解

开发区企业存在生产率优势吗?——基于开发区升格政策的准自然实验

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经济管理 2020年第10期42卷 59-76页

作者：柴泽阳孔令丞华东理工大学商学院上海200237

开发区升格作为一种外部制度环境的变动,通过政策比较优势对企业产生重要影响。文章利用2005—2013年的中国工业企业数据,以2009年启动的省级开发区升格政策为准自然实验,利用双重差分法考察了升格政策对开发区企业生产率的影响,并深入... 详细信息

开发区升格作为一种外部制度环境的变动,通过政策比较优势对企业产生重要影响。文章利用2005—2013年的中国工业企业数据,以2009年启动的省级开发区升格政策为准自然实验,利用双重差分法考察了升格政策对开发区企业生产率的影响,并深入探究了政策效果的异质性及其根源。研究发现:(1)开发区升格政策整体上并未促进区内企业生产率的提升。异质性检验表明,29.41%的开发区升格为正向政策效果,19.12%的开发区升格为负向政策效果,51.47%无显著影响。(2)开发区升格伴随的企业更替是导致政策效果差异的根源,具有高效率、成长型企业进入以及低效率企业退出特征的开发区升格会促进企业生产率增长;而具有低效率企业涌入特征的开发区升格会抑制企业生产率增长;具有非成长型企业进入特征的开发区升格对企业生产率无显著影响。(3)升格政策为正向效果的地区,其政府效率和市场化水平相对较高,有利于形成优胜劣汰的选择效应。本文的研究发现为地方政府推动开发区体制机制创新,实现地区经济高效率、高质量发展提供了参考依据。

关键词：开发区升格企业更替企业生产率双重差分

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略论山西古代壁画

山西档案 2012年第1期 22-34页

作者：柴泽俊

本文原发表于《山西文物》1982年第3期,后收入《柴泽俊古建筑修缮文集》(文物出版社,2009年)。鉴于本文在寺观壁画研究中的重要作用,本刊略加编辑,加以刊发,注释体例,一依其旧,以飨读者。

关键词：古代壁画山西文物出版社 2009年注释体例古建筑文集编辑

Uterine Artery Embolization with and without Local Methotrexate Infusion for the Treatment of Cesarean Scar Pregnancy

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Uterine Artery Embolization with and without Local Methotrex...

2015年泛长三角围产医学学术年会暨浙江省围产医学学术年会

作者： Feng Qi Ling-Zhi Zheng Wei Zhou Mei-Fen Wang ze-Ying chai Department of Gynecology and Obstetrics Taizhou Hospital of Zhejiang Province

Objective:To compare the clinical value of uterine artery embolization(UAE)with local methotrexate(MTX)infusion to embolization without MTX in the treatment of cesarean scar pregnancies(CSP).Materials and Methods:From January 2009 to December 2013,50 patients with CSP treated with UAE receiving or not receiving local MTX infusion before curettage were analyzed ***-two patients were offered UAE with local MTX infusion before curettage(UAE+MTX group),while 28 patients received UAE alone before curettage(UAE group).Clinical data and the outcomes were analyzed,followed by a brief review of the published literature summarizing what is known about UAE with and without MTX for the treatment of ***:UAE was successful in 42 of 50 cases(84%),with complications occurring in only five *** were no significant differences in the success rate,complication rate,recovery time,or hospitalization costs between the UAE+MTX group and the UAE ***,blood loss in the UAE+MTX group was significantly higher than in the UAE ***:UAE with or without local MTX infusion might be an effective treatment for *** with UAE alone,UAE with local MTX infusion did not dramatically improve the therapeutic effect of UAE.A larger and more comprehensive random control study is warranted to better evaluate the therapeutic effects of UAE in the treatment of CSP.

关键词： Cesarean scar pregnancy uterine artery embolization methotrexate curettage

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GCr15轴承钢中碳化物的定量分析

机械工程材料 2015年第1期39卷 42-45页

作者：柴泽巴发海上海材料研究所上海200437

为了准确测定GCr15轴承钢中残余奥氏体的含量,必须先测出其碳化物的含量。采用计算法、金相法及电解萃取法分别测定了球化退火态GCr15轴承钢中碳化物的含量,并对这三种方法进行了比较。结果表明：球化退火态GCr15轴承钢中的碳化物体积... 详细信息

为了准确测定GCr15轴承钢中残余奥氏体的含量,必须先测出其碳化物的含量。采用计算法、金相法及电解萃取法分别测定了球化退火态GCr15轴承钢中碳化物的含量,并对这三种方法进行了比较。结果表明：球化退火态GCr15轴承钢中的碳化物体积分数为13.51%~16.61%;金相法只可估算碳化物的含量,准确性较差;计算法模拟计算的是材料在热力学平衡态条件下的相含量,只可作为其它方法的参照;电解萃取法是一种能相对比较准确测定碳化物含量的分析方法。

关键词： GCr15轴承钢碳化物金相法电解萃取法