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Journal of Materials Science & Technology 2022年第1期96卷 212-225页

作者： Jinshuo Zhang Guohua Wu Liang Zhang Xiaolong Zhang chunchang shi Xin Tong National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites School of Materials Science andEngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Innovation Institute for Materials Shanghai200444China

A dramatic improvement of strength and ductility of cast Al-2.5Li-1.5Cu-1Zn-0.5Mg-0.15 Zr alloy was obtained by the collaboration of Sc-alloying and optimized ageing *** and independent influence of Sc-alloying and different ageing temperatures were *** results revealed that a substantial increase was realized in the hardness of Sc-containing alloy,and the ageing response time was only influenced by ageing *** and heterogeneousδ'(Al_(3)Li),wideδ'-precipitation free zones(δ'-PFZs),and a large amount of T_(1)(Al_(2)CuLi)precipitates were observed in Sc-containing alloy aged at 175℃,which resulted in superior yield strength and poor *** Sc-containing alloy obtained an excellent combination of ductility(elongation=8.2%)and tensile strength(ultimate strength=565 MPa)suffered to 150℃ ageing for 64 *** increase in the elongation was mainly due to the combined effect of grain refining,much finerδ',and extremely narrowδ'-PFZs(<10 nm),while the higher strength was mainly attributed to the formation of Al_(3)(Sc,Zr,Li)composite particles and a large amount of S'(Al_(2)CuMg)***,the enhancement of the different ageing temperature(150℃ and 175℃)on the mechanical properties of the alloys without Sc addition was not obvious.

关键词： Cast Al-Li-Cu alloy δ’-PFZs Mechanical properties Cu-containing phases Microstructure evolutions

Effect of Different Ageing Processes on Microstructure and Mechanical Properties of Cast Al–3Li–2Cu–0.2Zr Alloy

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Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1243-1251页

作者： Guohua Wu chunchang shi Liang Zhang Wencai Liu Antao Chen Wenjiang Ding National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

The effect of different ageing processes on microstructure and mechanical properties of cast Al–3 Li–2 Cu–0.2 Zr alloy was investigated using transmission electron microscopy and tensile tests. The results showed that the mean size of δ′-Al3 Li particles and the number density of Cu-rich precipitates both increased with increasing ageing temperature from 150 to 190 °C for 24 h, resulting in increasingly high strength. In contrast, the ductility deteriorated with the increase in ageing temperature as a result of the intensified planar slip. The duplex low-to-high ageing treatment(120 °C for 6 h followed by 160 °C for 24 h) was shown to be beneficial to the ductility compared with the corresponding single-stage ageing treatment(160 °C for 24 h). The reduced slip length induced by the precipitation of θ′-Al 2 Cu phases was found to be mainly responsible for this ductility improvement.

关键词： Cast Al–Li alloy Ageing treatment Precipitates Slip length

青海东部上喇家村黄土剖面全新世野火历史及人类活动

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第四纪研究 2024年第1期44卷 72-83页

作者：雷秋景谭志海张琪石斌黄春长西安工程大学环境与化学工程学院陕西西安710600 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室陕西西安710061 陕西师范大学地理与旅游学院陕西西安710119

由于不同燃烧指标存在明显的差异,致使人们对于火燃烧方式的理解尚不确定。本研究选取黄河上游青海上喇家典型剖面(深度464 cm,年代范围14.5~0 ka B.P.)为对象,结合炭屑和黑碳以及古生态指标,揭示该区域全新世以来的野火历史演变过程。... 详细信息

由于不同燃烧指标存在明显的差异,致使人们对于火燃烧方式的理解尚不确定。本研究选取黄河上游青海上喇家典型剖面(深度464 cm,年代范围14.5~0 ka B.P.)为对象,结合炭屑和黑碳以及古生态指标,揭示该区域全新世以来的野火历史演变过程。研究结果表明末次冰期和全新世早期,气候较为干旱,以明烧为特征的草原区域野火时常发生,与东亚季风气候所控制燃料特征和湿度密切相关。全新世中期,气候较现在温暖而湿润,生物成壤作用强烈,该地区整体上自然野火发生处于较低水平。其中,4200~3850 a B.P.和3400~3000 a B.P.这两个阶段的粗颗粒炭屑通量峰值分别是齐家文化中晚期(4200~3800 a B.P.)和辛店文化时期(3400~2700 a B.P.)人类频繁放火烧荒和开垦农田以及生活等活动的结果;而3850~3600 a B.P.阶段以焖烧为特征的低强度野火发生,与气候持续干旱和人类森林砍伐活动加剧有关。与此同时,该区域遭遇2次大规模的地震和山洪泥流地质灾害,生态环境恶化,使得农耕为主的齐家文化被半农半畜牧的辛店文化所替代,从而导致该期间炭屑通量整体下降。全新世晚期,气候进一步干旱,1500年以来本地大幅度生物质燃烧增加与农业扩张和耕地面积增大密切相关。总之,全新世中期先前人类长期频繁森林砍伐活动所诱发的低强度焖烧火模式是导致该区域植被减少和土地退化的不容忽视的重要因素,而东亚季风所控制的季节性降水变化仍是野火发生必要条件。

关键词：炭屑黑碳燃烧方式全新世气候变化

High depolarization temperature and superior piezoelectric performance with complex structural evolution in BiFeO_(3)-PbTiO_(3)-(Sr0.7Bi0.2,0.1)TiO_(3) systems

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Journal of Materiomics 2022年第6期8卷 1260-1268页

作者： Hongwei shi Feng Li Xinliang Yang Mingsheng Long Lei Shan chunchang Wang Jiwei Zhai Information Materials and Intelligent Sensing Laboratory of Anhui Province Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationInstitutes of Physical Science and Information TechnologyAnhui UniversityHefei230601China Laboratory of Dielectric Functional Materials School of Materials Science and EngineeringAnhui UniversityHefei230601China School of Materials Science&Engineering Tongji University4800 Caoan RoadShanghai201804China

Bismuth ferriteebased ferroelectric ceramics are considered strong competitors in highetemperature piezoelectric applications that benefits from their high depolarization temperature(Td),but problems of large conductivity and low piezoelectric coefficient(d33)should be ***_(3)ePbTiO_(3)ex(Sr0.7Bi0.2,0.1)TiO_(3)(BFePTexSBT)ternary system are designed in this work that successfully resolves this tough *** refinements show that this system exhibits multiphase coexistence with complex structural transition among rhombohedral,tetragonal and pseudocubic ***,a high Td~320℃ and d33~236℃/N are synergistically optimized in x=0.20 composition near pseudoephase boundary,which are indicated by multiescale techniques(phase structure,dielectric analysis etc.).What'smore,dual electrostrain peaks appear at separate phase boundaries for x=0.20 and 0.66 compositions with distinct piezo/ferroelectric *** law and piezoelectric force microscopy analysis clarify that the optimal electrostrain performance for both critical compositions are dominated by intrinsic(x=0.20)and extrinsic(x=0.66)contributions,*** work not only provides a new BFePTexSBT system with a high Td and superior d33 that are promising candidates in highetemperature actuator and sensor applications,but also presents a possibility of multiphaseecoexistence established exotic macroscopic performances.

关键词： BiFeO_(3)-based Piezoelectric Electrostrain Multiphaseecoexistence Domain switching

定量测江河中阴离子表面活性剂所用高效试剂的合成

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化学试剂 1985年第4期 221-222页

作者：黄治清杨春常李晰石桂林辽宁大学化学系

多年来,阴离子表面活性剂大量流入江河湖中,污染日趋严重。为了准确测定其含量,1979年有人合成了MDEPAP、NDEPAP和MANPAP高效阳离子试剂。这类试剂可将水中的阴离子表面活性剂缔合出来,溶剂提取后进行定量测试,检测范围为0～1.5×10-5M... 详细信息

多年来,阴离子表面活性剂大量流入江河湖中,污染日趋严重。为了准确测定其含量,1979年有人合成了MDEPAP、NDEPAP和MANPAP高效阳离子试剂。这类试剂可将水中的阴离子表面活性剂缔合出来,溶剂提取后进行定量测试,检测范围为0～1.5×10-5M。与标准亚甲基蓝测定法（简称JIS法）相比,具有快速、简单、灵敏度高、稳定性强等特点。我们从1981年先后合成了MDEPAP、EDEPAP和BDP等试剂。本文主要介绍其合成方法和测试结果。

关键词：阴离子表面活性剂偶氮合成方法试剂

Enzyme-Triggered Fluorescence Turn-on： A Probe for Specifically Imaging Ovarian-Cancer-Related γ-Glutamyltranspeptidase

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Chinese Journal of Chemistry 2017年第11期35卷 1711-1716页

作者： Jie Tian Qinglong Yan Ying Zhu Jichao Zhang Jiao Li Ben shi Ge Xu Chunhai Fan chunchang Zhao Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science & Technology Shanghai 200237 China Division of Physical Biology & Bioimaging Center Shanghai Synchrotron Radiation Facility CAS Key Laborato- ry of lnterfacial Physics and Technology Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

A fluorescent turn-on probe for specifically targeting γ-glutamyltranspeptidase （GGT） was designed and synthe- sized by integrating boron-dipyrromethene （BODIPY） as a chromophore and glutathione （GSH） as the GGT sub- strate. GGT-catalyzed the cleavage of the γ-glutamyl bond and generated the aromatic hydrocarbon transfer between the sulfur and the nitrogen atom in BODIPY, leading to distinct optical changes. Such specific responsiveness pro- vides an easily distinguishable fluorescence signal to visualize the GGT activity in living cells and differentiate GGT-positive cancer cells from GGT-negative cells.

关键词： fluorescence turn-on GGT the aromatic hydrocarbon transfer living cells specifically targeting

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基于博弈论的EPC项目评标方法研究

项目管理技术 2022年第6期20卷 103-107页

作者：韦春昌聂春龙李佩琪石爽南华大学湖南衡阳421001

以我国现行的招投标法中常用的评标法为研究对象,分析两种评标方法存在的问题以及EPC模式的特点,研究EPC项目招标的综合评标法,重新构建评标指标体系,运用博弈论组合赋权技术对评标指标再赋权,最后结合实例验证,结果表明与实际评标结果... 详细信息

以我国现行的招投标法中常用的评标法为研究对象,分析两种评标方法存在的问题以及EPC模式的特点,研究EPC项目招标的综合评标法,重新构建评标指标体系,运用博弈论组合赋权技术对评标指标再赋权,最后结合实例验证,结果表明与实际评标结果一致。该方法降低了投标报价比重,增加了质量技术管理方面的权重值,对引导投标单位以质量技术管理等为指导的良性竞争有一定的现实意义。

关键词： EPC模式综合评标法博弈论项目评标

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PMC模式下工程招标风险评价研究

科技通报 2022年第9期38卷 60-64页

作者：韦春昌聂春龙李佩琪石爽南华大学土木工程学院湖南衡阳421001

以PMC模式下的工程招标为研究对象,分析了此模式下工程招标的特点,从PMC管理承包商的视角,识别工程招标存在的风险并建立招标风险评价体系,然后运用G1法和熵权法确定指标权重,融合博弈论思想进行组合赋权,再结合灰色聚类法构建风险评价... 详细信息

以PMC模式下的工程招标为研究对象,分析了此模式下工程招标的特点,从PMC管理承包商的视角,识别工程招标存在的风险并建立招标风险评价体系,然后运用G1法和熵权法确定指标权重,融合博弈论思想进行组合赋权,再结合灰色聚类法构建风险评价模型。最后将该模型应用于实例,算出各风险因素的指标权重和风险评价等级,针对评价结果分析并提出相应风险防控或转移措施,对国内PMC模式下的工程招标风险管控和PMC模式的推广应用有一定的实用意义。

关键词： PMC模式工程招标博弈论灰色聚类法风险评价

Visualizing Glioma Margins by Real-Time Tracking of γ-Glutamyltranspeptidase Activity

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Visualizing Glioma Margins by Real-Time Tracking of γ-Gluta...

黄河龙门段商周转折时期的古洪水事件及气候背景

第十三届中国医师协会神经外科医师年会

作者： Yingchao Liu Jie Tan Yi Zhang Jianfeng Zhuang Mingxu Ge Ben shi Jiao Li Ge Xu Shangchen Xu Chunhai Fan chunchang Zhao Department of Neurosurgery Provincial Hospital Affiliated to Shandong University Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chemistry and Molecular EngineeringEast China University of Science & Technology Shandong Medical Imaging Research Institute Shandong University CAS Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied Physics Chinese Academy of Sciences

Distinguishing tumor from adjacent non-cancerous tissue can be problematic during surgical treatment of malignant ***,a novel approach to selective discrimination is *** goal of this study was to determine whether a fluorescent probe activated by γ-Glutamyltranspeptidase（GGT）,an enzyme that is overexpressed on glioma cell membranes but only minimally expressed in normal brain tissue,could be used to visualize glioma ***,we showed that the GGT-activatable fluorescent probe（NC-B-Cys-Glu）provided real-time in situ tracking of enzyme activity that accurately distinguished glioma from healthy brain ***-B-Cys-Glu,which featured distinct ratiometric fluorescence responsiveness after interaction with GGT,enabled monitoring of GGT activity in living cells and differentiation between glioma and normal *** spraying of NC-B-Cys-Glu facilitated real-time in vivo identification of orthotopic glioblastomas in a mouse ***,the tumor,infiltrating area and surrounding normal tissue were distinguished in clinical glioma samples by real-time tracking of GGT *** coupled with auto fluorescence bronchoscopy,NC-B-Cys-Glu offered diagnostic value for cancers overexpressing ***,NC-B-Cys-Glu might offer a promising tool to guide maximal yet precise tumor resection while sparing non-cancerous tissue.

关键词： Glioma margins Activatable probe γ-Glutamyltranspeptidase real-time clinical

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湖泊科学 2017年第1期29卷 234-245页

作者：石彬楠黄春长庞奖励查小春周亚利张玉柱刘雯瑾陕西师范大学旅游与环境学院西安710062

通过野外观察研究,在黄河中游晋陕峡谷龙门段乡宁-韩城大桥西端支沟内,发现了全新世古洪水滞流沉积物.通过野外观察和室内实验分析,证明它们是黄河特大洪水悬移质泥沙在高水位滞流环境下的沉积物,记录了黄河晋陕峡谷段一期4次特大古洪... 详细信息

通过野外观察研究,在黄河中游晋陕峡谷龙门段乡宁-韩城大桥西端支沟内,发现了全新世古洪水滞流沉积物.通过野外观察和室内实验分析,证明它们是黄河特大洪水悬移质泥沙在高水位滞流环境下的沉积物,记录了黄河晋陕峡谷段一期4次特大古洪水事件.通过地层学对比分析和光释光测年,确定这4次洪水发生在全新世中期-晚期转折阶段,即我国历史上商代末期-西周初期的气候突变转型期.利用"古洪水滞流沉积物厚度含沙量法"恢复古洪水洪峰水位,运用HEC-RAS模型估算出4次古洪水事件洪峰流量介于46280~48800 m^3/s之间.这些成果为黄河中游地区的防洪减灾、水资源开发利用、流域生态环境综合治理等方面提供了可靠的超长尺度水文数据.这为深入理解黄河流域水文系统对于全球变化的响应规律提供了新的证据.

关键词：古洪水商末滞流沉积物水文学黄河