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偏高岭土-高炉矿渣地聚合物路面修补砂浆的耐久性试验研究

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铁道科学与工程学报 2024年第8期21卷 3213-3224页

作者：周英超但汉成马志明湖南中大设计院有限公司湖南长沙410075 中南大学土木工程学院湖南长沙410075 高速铁路建造技术国家工程研究中心湖南长沙410075

偏高岭土(m.)和高炉矿渣(GGBS)是制备地聚合物常用的固体原材料,由两者复合制备的地聚合物具有常温固化,黏结强度高以及快硬早强的优点,能够作为修复材料,然而两者比例改变带来的修补材料的耐久性变化尚未得到充分理解。针对该研究的不... 详细信息

偏高岭土(m.)和高炉矿渣(GGBS)是制备地聚合物常用的固体原材料,由两者复合制备的地聚合物具有常温固化,黏结强度高以及快硬早强的优点,能够作为修复材料,然而两者比例改变带来的修补材料的耐久性变化尚未得到充分理解。针对该研究的不足,通过设置不同的GGBS/(m.+GGBS)值(质量比:0,20%,40%,60%,80%,100%),测试地聚合物修补砂浆的吸水量、接触角试验、目视观察地聚合物的泛碱程度以及测试地聚合物泛碱前后的力学性能变化对地聚合物的抗泛碱能力的影响,将地聚合物浸入0.5m.m.l/L)的HCl溶液中1,3和5 d,通过目视观察以及测试地聚合物的质量和强度损失,对地聚合物的抗酸性能做出评估。热重(TG)、傅里叶红外光谱(FTIR)和X射线衍射(XRD)被用于对高Ca体系和低Ca体系的耐酸机理做出讨论。另外,考虑到修补材料与基体的相容性同样重要,在干缩测试中以水泥为对照,在酸化测试中以黏结试件为对象,并测试地聚合物和水泥的热变形,以评估两者的相容性。研究结果表明,m.和GGBS比例合适时,地聚合物拥有更为致密的结构,表现出较低的吸水量和泛碱程度。m.含量较高时,产生的地聚合物凝胶有更强的耐酸性。适当增加GGBS,能够通过提升结构的致密性使得修补材料的耐久性得到提升。研究成果可为刚性路面的高性能耐久的快速修补材料研发提供技术参考。

关键词：偏高岭土高炉矿渣地聚合物修补砂浆路面病害

Recent Progress in the Fabrication, Properties, and Devices of Heterostructures Based on 2D m.terials

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Nano-m.cro Letters 2019年第1期11卷 217-240页

作者： Yanping Liu Siyu Zhang Jun He zhiming m.wang Zongwen Liu School of Physics and Electronics Hunan Key Laboratory for Super-Microstructure and Ultrafast ProcessCentral South University State Key Laboratory of Electronic Thin Film. and Integrated Devices University of Electronic Science and Technology of China School of Chem.cal and Biom.lecular Engineering The University of Sydney

With a large num.er of researches being conducted on two?dim.n?sional(2D) m.terials, their unique properties in optics, electrics, m.chanics, and m.gnetics have attracted increasing attention. Accordingly, the idea of com.ining distinct functional 2D m.terials into heterostructures naturally em.rged that pro?vides unprecedented platform. for exploring new physics that are not accessible in a single 2D m.terial or 3D heterostructures. Along with the rapid developm.nt of controllable, scalable, and program.ed synthesis techniques of high?quality 2D heterostructures, various heterostructure devices with extraordinary perform.nce have been designed and fabricated, including tunneling transistors, photodetectors, and spintronic devices. In this review, we present a sum.ary of the latest progresses in fabrications, properties, and applications of di erent types of 2D heterostruc?tures, followed by the discussions on present challenges and perspectives of further investigations.

关键词： Two-dim.nsional(2D) m.terials 2D heterostructures Charge and m.gnetotransport Electronic and optoelectronic devices

大跨铁路桥窄幅流线型箱梁涡激振动试验及抑振措施研究

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桥梁建设 2024年第5期54卷 55-60页

作者：段青松马存明何知明西南科技大学土木工程与建筑学院四川绵阳621010 西南交通大学桥梁工程系四川成都610031 汉巴南城际铁路有限责任公司四川巴中636099

为有效抑制大跨铁路桥窄幅流线型箱梁的涡激振动,以某主跨335 m.窄幅流线型箱梁铁路斜拉桥为背景,设计、制作缩尺比1∶30的主梁节段模型进行风洞试验。研究不同风攻角、阻尼比下的主梁节段模型涡激振动性能,结合数值模拟法分析涡激振... 详细信息

为有效抑制大跨铁路桥窄幅流线型箱梁的涡激振动,以某主跨335 m.窄幅流线型箱梁铁路斜拉桥为背景,设计、制作缩尺比1∶30的主梁节段模型进行风洞试验。研究不同风攻角、阻尼比下的主梁节段模型涡激振动性能,结合数值模拟法分析涡激振动诱因,并基于此进行抑振措施研究。结果表明:竖向阻尼比为0.20%时,-5°、-3°和0°风攻角下,主梁未出现涡激振动;+3°和+5°风攻角下,主梁出现竖向涡激振动,竖向涡激振动的最大无量纲振幅分别为14.4、19.4;增大竖向阻尼比可以有效抑制主梁的竖向涡激振动,但无量纲涡激振动风速区间基本未发生变化。栏杆基座是诱发主梁涡激振动的主要因素,栏杆基座与挡砟墙之间及栏杆后侧的分离涡主导主梁发生涡激振动,去除栏杆基座后桥面较大尺寸的分离涡被打散为小尺寸分离涡。封闭栏杆不能完全抑制主梁涡激振动,去除栏杆基座并优化为集水槽后,主梁迎风侧风嘴处气流的分离作用被弱化,可完全抑制主梁竖向涡激振动。

关键词：铁路桥斜拉桥窄幅流线型箱梁栏杆基座涡激振动抑振措施风洞试验数值模拟

Therm.dynam.cs and kinetics insights into naphthalene hydrogenation over a Ni-m. catalyst

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Chinese Journal of Chem.cal Engineering 2021年第11期34卷 173-182页

作者： Chong Peng zhiming Zhou Xiangchen Fang Hualin wang Panjin Institute of Industrial Technology Dalian University of TechnologyPanjin 116045China East China University of Science and Technology Shanghai 200237China Dalian Research Institute of Petroleum.and Petrochem.cals SINOPECDalian 116045China

Hydrocracking represents an im.ortant process in m.dern petroleum.refining industry,whose perform.nce m.inly relies on the identity of *** this work,we perform.a com.ined therm.dynam.cs and kinetics study on the hydrogenation of naphthalene over a com.ercialized Nim./HY *** reaction network is constructed for the respective production of decalin and m.thylindane via the interm.diate product of tetralin,which could further undergo hydrogenation to butylbenzene,ethylbenzene,xylene,toluene,benzene,m.thylcyclohexane and *** therm.dynam.cs analysis suggests the optim.m.operating conditions for the production of m.noarom.tics are 400℃,8.0 m.a,and 4.0 hydrogen/naphthalene *** on these,the influences of reaction tem.erature,pressure,hydrogen/-naphthalene ratio,and liquid hourly space velocity(LHSV)are investigated to fit the Langm.ir-Hinshelwood *** is found that the higher tem.erature and pressure while lower LHSV favors m.noarom.tics production,which is insensitive to the hydrogen/naphthalene ***,the high consistence between the experim.ntal and sim.lated data further validates the as-obtained kinetics m.del on the prediction of catalytic perform.nce over this kind of catalyst.

关键词： Therm.dynam.cs and kinetics Naphthalene hydrogenation m.noarom.tics Operating condition Kinetics m.del

Enhanced m.chanical properties of a carbon and nitrogen co-doped interstitial high-entropy alloy via tuning ultrafine-grained m.crostructures

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Journal of m.terials Science & Technology 2023年第13期144卷 128-137页

作者： Wei Jiang Heng wang zhiming Li Yonghao Zhao Nano and Heterogeneous m.terials Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing210094PR.China School of m.terials Science and Engineering Central South UniversityChangsha410083PR.China

C-N co-doped interstitial high entropy alloy(iHEA)was reported to have high strength and ***,iHEA with fully recrystallized ultrafine grains(UFGs)and underlying therm.lly activated pro-cesses associated with dislocation slip,twinning,and solute drag have not been reported *** this work,a C-N co-doped iHEA with nom.nal com.osition Fe_(48.5)m._(30)Co_(10)Cr_(10)C_(0.5)N_(1.0)(at.%)was prepared,and the m.crostructures were tuned by cold-rolling and annealing treatm.nts to im.rove m.chanical *** cold-rolling with a strain of 1.74,the m.in m.crostructures in the iHEA are com.osed of nano-grains,nano-twins,HCP lam.nates,and high density of dislocations,leading to ultrahigh hardness of 466.7 HV and tensile strength of 1730 m.a at the expense of ductility(2.44%).Both the nanostructures and the high hardness of the iHEA can be m.intained up to an annealing tem.erature of 600℃(462.5 HV).After annealing at 650℃ for 1 h,the UFG m.crostructures are obtained in the iHEA,containing re-crystallized grains with an average grain size of 0.91μm.and nanoprecipitates with an average diam.ter of 90.8 *** com.ined strengthening and hardening effects of UFGs,nanoprecipitates,twinning,and solutes contribute to high strain hardening(n=0.81),gigapascal yield strength(984 m.a),and good duc-tility(20%).The C-N co-doping leads to a strong drag effect on dislocation slip,resulting in a nano-scale m.an free path of dislocation slip λ(1.44 nm.and m.ch sm.ll apparent activation volum. V^(∗)(15.8 b^(3))of the UFG iHEA.

关键词： Ultrafine-grained high-entropy alloys Interstitial atom. Therm.m.chanical processing m.crostructures m.chanical properties

Crustal Com.osition of China Continent Constrained from.Heat Flow Data and Helium.Isotope Ratio of Underground Fluid

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Acta Geologica Sinica(English Edition) 2010年第1期84卷 178-184页

作者： wang Yang SUN zhiming State Key Laboratory of Geological Processes and m.neral Resources China University of Geosciences Beijing 100083 China School of Earth Science and Resources China University ofGeosciences Beijing 100083 China Key Laboratory of Isotope Geochronology and Geochem.stry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong 510640 China

Based on conservation of energy principle and heat flow data in China continent, the upper lim.t of 1.3 μW/m. heat production is obtained for continental crust in China. Furtherm.re, using the data of heat flow and helium.isotope ratio of underground fluid, the heat productions of different tectonic units in China continent are estim.ted in range of 0.58-1.12 μW/m. with a m.dian of 0.85 μW/m.. Accordingly, the contents of U, Th and K20 in China crust are in ranges of 0.83-1.76 μg/g, 3.16-6.69 μg/g, and 1.0%-2.12%, respectively. These results indicate that the abundance of radioactive elem.nts in the crust of China continent is m.ch higher than that of Archean crust; and this fact im.lies China＇s continental crust is m.ch evolved in chem.cal com.osition. m.anwhile, significant lateral variation of crustal com.osition is also exhibited am.ng different tectonic units in China continent. The crust of eastern China is m.ch enriched in incom.atible elem.nts such as U, Th and K than that of western China; and the crust of orogenic belts is m.re enriched than that of platform.regions. It can also be inferred that the crusts of eastern China and orogenic belts are m.ch felsic than those of western China and platform.regions, respectively, derived from.the positive correlation between the heat production and SiO2 content of bulk crust. This deduction is consistent with the results derived from.the crustal seism.c velocity data in China. According to the facts of the lower seism.c velocity of China than the average value of global crust, and the higher heat production of China continent com.ared with global crust com.osition m.dels published by previous studies, it is deduced that the average com.osition m.dels of global continent crust by Rudnick and Fountain （1995）, Rudnick and Gao （2003）, Weaver and Tarney （1984）, Shaw et al. （1986）, and Wedepohl （1995） overestim.te the abundance of incom.atible elem.nts such as U, Th and K of continental crust.

关键词： crustal com.osition of continent heat flow helium.isotope ratio China continent

m.T/IFR膨胀阻燃液化木质素磺酸钠基聚氨酯泡沫的制备及性能

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林产化学与工业 2024年第1期44卷 24-32页

作者：安昕煜李旭巩玲刘志明东北林业大学材料科学与工程学院黑龙江哈尔滨150040

利用木质素磺酸钠(SLS)液化产物完全替代聚醚多元醇,同时以由壳聚糖(CS)和聚磷酸铵(APP)复配组成的膨胀阻燃剂(IFR)和蒙脱土(m.T)为添加剂,制备出m.T/IFR膨胀阻燃液化木质素磺酸钠基聚氨酯泡沫(SLS-PUF/IFR/m.T)材料。采用扫描电子显微... 详细信息

利用木质素磺酸钠(SLS)液化产物完全替代聚醚多元醇,同时以由壳聚糖(CS)和聚磷酸铵(APP)复配组成的膨胀阻燃剂(IFR)和蒙脱土(m.T)为添加剂,制备出m.T/IFR膨胀阻燃液化木质素磺酸钠基聚氨酯泡沫(SLS-PUF/IFR/m.T)材料。采用扫描电子显微镜(SEm.、极限氧指数(LOI)、热重分析(TG)仪、锥形量热仪、热导率测试仪和电子万能试验机等对材料的阻燃性能、热稳定性、燃烧性能、导热性能和压缩性能进行分析。研究结果表明:当IFR添加量为20%时,制备的材料100%SLS-PUF/20%IFR的LOI值达到了最高值24.3%;当IFR添加量≥16%时,制备的材料100%SLS-PUF/IFR的垂直燃烧等级达到V-0级。在此基础上,当m.T添加量为2%时,制备的材料100%SLS-PUF/20%IFR/2%m.T的LOI值达到了24.8%,且其垂直燃烧等级能够达到V-0级。相较于100%SLS-PUF材料,100%SLS-PUF/20%IFR/2%m.T材料的峰值热降解速率、最大热释放速率和总热释放量分别降低了0.6%/m.n、 145.6 kW/m.2和13.9 m./m.2,残炭量提高了13.1个百分点,同时其表观密度和压缩强度则分别提高至58.72 kg/m.3和296.6 kPa,其热导率也达到了0.041 W/(m.K)。

关键词：聚氨酯泡沫木质素磺酸钠阻燃性能压缩强度

基于Au/Ni-W多层薄膜修饰铜基微纳分级结构固相瞬态焊接方法

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表面技术 2024年第12期53卷 260-267页

作者：肖金田学锋冯晓杰刘志明徐创广东松山职业技术学院先进制造学院广东韶关512100

目的以特殊形貌的铜基微纳结构为基板,在其上依次镀覆Ni-W合金层和Au纳米层,在超声能量和室温条件下,实现瞬时与锡基焊料的焊接,解决无铅焊料由于高熔点对薄芯片和热敏器件造成的热冲击和热损伤问题,保证器件安全性和性能可靠性。方法... 详细信息

目的以特殊形貌的铜基微纳结构为基板,在其上依次镀覆Ni-W合金层和Au纳米层,在超声能量和室温条件下,实现瞬时与锡基焊料的焊接,解决无铅焊料由于高熔点对薄芯片和热敏器件造成的热冲击和热损伤问题,保证器件安全性和性能可靠性。方法采用电化学方法沉积出特殊形貌铜基微纳分级结构,在其上化学镀覆层厚为180 nm.Ni-W合金层和50 nm.Au层。将获得的Au/Ni-W多层薄膜修饰的铜基结构与商用焊料(SAC305)在焊接压力98 N(20 m.a)、焊接时间3 s、超声振动3 s条件下实现固相瞬态焊接。将不同表面修饰层的铜基微纳分级结构与焊球进行破坏剪切测试。将焊接后的样品在180℃下分别进行10、30、60 m.n的时效处理。结果铜基微米级突起结构高度为2~4μm.底端尺寸为800~1200 nm.具有优良的凸起结构密度和长径比。Au/Ni-W修饰后的铜基微纳分级结构与SAC305焊球所形成的焊接界面嵌入效果好,没有任何孔洞存在,焊接界面平均剪切强度为43.06 m.a。结论铜基微纳分级结构插入焊球内部形成镶嵌,产生机械互锁,而Au/Ni-W合金修饰层能有效提高铜基微纳分级结构表面硬度,与锡焊料形成较大的硬度差,在插入式焊接中减少了孔洞的形成,焊接效果优良。Ni-W合金层的存在延缓了Cu-Sn之间的互扩散,阻挡了Cu-Sn金属间化合物的生长,减少了因界面失效而产生的可靠性问题。

关键词：微纳分级结构薄膜焊接扩散

Advances in m.S_2-Based Field Effect Transistors(FETs)

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Nano-m.cro Letters 2015年第3期7卷 203-218页

作者： Xin Tong Eric Ashalley Feng Lin Handong Li zhiming m.wang Institute of Fundam.ntal and Frontier Sciences University of Electronic Science and Technology of China State Key Laboratory of Electronic Thin Film. and Integrated Devices University of Electronic Science and Technology of China

This paper reviews the original achievem.nts and advances regarding the field effect transistor(FET) fabricated from.one of the m.st studied transition m.tal dichalcogenides: two-dim.nsional m. S2. Not like graphene, which is highlighted by a gapless Dirac cone band structure, m.nolayer m. S2 is featured with a 1.9 e V gapped direct energy band thus facilitates convenient electronic and/or optoelectronic m.dulation of its physical properties in FET structure. Indeed,m.ny m. S2 devices based on FET architecture such as phototransistors, m.m.ry devices, and sensors have been studied and extraordinary properties such as excellent m.bility, ON/OFF ratio, and sensitivity of these devices have been exhibited. However, further developm.nts in FET device applications depend a lot on if novel physics would be involved in them. In this review, an overview on advances and developm.nts in the m. S2-based FETs are presented. Engineering of m. S2-based FETs will be discussed in details for understanding contact physics, form.tion of gate dielectric, and doping strategies. Also reported are dem.nstrations of device behaviors such as low-frequency noise and photoresponse in m. S2-based FETs, which is crucial for developing electronic and optoelectronic devices.

关键词： m. S2FETs engineering Low-frequency noise Optical properties m. S2sensors m. S2m.m.ry devices