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Threshold of climate extremes that impact vegetation productivity over the Tibetan Plateau

Science China Earth Sciences 2024年第6期67卷 1967-1977页

作者： Zhenggang PIAO Xiangyi LI Hao XU Kai WANG Shuchang TANG Fei KAN songbai hong College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Vegetation growth is adversely impacted by multiple climate extremes related to the water and thermal stress over the Tibetan Plateau(TP).However,it remains unknown at which stress level these climate extremes can trigger the abrupt shifts of vegetation response to climate extremes and result in the maximum vegetation response across TP.To fill this knowledge gap,we combined the hydrometeorological data and the satellite-derived vegetation index to detect two critical thresholds that determine the response of vegetation productivity to droughts,high-temperature extremes,and low-temperature extremes,respectively,during 2001-2018.Our results show that the response of vegetation productivity to droughts rapidly increases once crossing -1.41±0.6 standard deviation(σ)below the normal conditions of soil moisture.When crossing-2.98σ±0.9σ,vegetation productivity is maximum damaged by droughts.High-temperature extremes,which have the two thresholds of 1.34σ±0.4σand 2.31σ±0.4σover TP,are suggested to trigger the strong response of vegetation productivity at a milder stress level than low-temperature extremes(two thresholds:-1.44σ±0.5σand-2.53σ±0.8σ).Moreover,we found the compounded effects of soil moisture deficit in reducing the threshold values of both high-and low-temperature extremes.Based on the derived thresholds of climate extremes that impact vegetation productivity,Earth System Models project that southwestern TP and part of the northeastern TP will become the hotspots with a high exposure risk to climate extremes by 2100.This study deciphers the high-impact extreme climates using two important thresholds across TP,which advances the understanding of the vegetation response to different climate extremes and provides a paradigm for assessing the impacts of climate extremes on regional ecosystems.

关键词： Tibetan Plateau Climate extremes Thresholds Vegetation productivity

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The greenhouse gas budget for China's terrestrial ecosystems

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National Science Review 2023年第12期10卷 55-57页

作者： Xuhui Wang Yuanyi Gao Kai Wang Yuxing Sang Yilong Wang Yuzhong Zhang songbai hong Yao Zhang Wenping Yuan Institute of Carbon Neutrality Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE) Institute of Tibetan Plateau ResearchChinese Academy of Sciences Key Laboratory of Coastal Environment and Resources of Zhejiang Province School of EngineeringWestlake University Institute of Advanced Technology Westlake Institute for Advanced Study School of Atmospheric Sciences Sun Yat-sen University

The increased atmospheric concentrations of greenhouse gases (GHGs,including CO2, CH4 and N2O) are unequivocally the major driving forces of climate warming [1]. These GHGs originate not only from the use of fossil fuels, but also from disturbances to and management of terrestrial ecosystems.Recent evidence suggests that terrestrial ecosystems,

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高溶质含量Cu-Ni-Si合金热压缩变形行为研究

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铸造技术 2024年第1期45卷 73-80页

作者：于倩彭丽军曹祎程刘峰罗毅洪松柏中国有研科技集团有限公司有色金属材料制备加工国家重点实验室北京100088 有研工程技术研究院有限公司北京101407 北京有色金属研究总院北京100088 宁波兴业盛泰集团有限公司浙江宁波315336

电连接器用铜合金为目前5G通讯、新能源汽车等领域的重要材料,Cu-Ni-Si系合金因其优异的力学电学性能、良好的抗应力松弛性能成为该研究背景下广泛应用的材料。目前尚缺乏热变形制度对该合金显微组织影响机理的研究。本文研究了变形温度... 详细信息

电连接器用铜合金为目前5G通讯、新能源汽车等领域的重要材料,Cu-Ni-Si系合金因其优异的力学电学性能、良好的抗应力松弛性能成为该研究背景下广泛应用的材料。目前尚缺乏热变形制度对该合金显微组织影响机理的研究。本文研究了变形温度在600~950℃、应变速率在0.01~10.00 s-1条件下的高溶质含量Cu-Ni-Si合金铸锭的热变形行为,发现在高应变速率下,硬化和软化在变形过程中交替占据主导地位,流变应力呈“波浪形”变化。建立了合金的热变形本构方程和热加工图,获得了高溶质含量Cu-Ni-Si合金的热变形温度为900~950℃,探究了不同变形条件下合金热变形过程的软化机制。结果表明,在950℃低应变速率时,合金的再结晶主要以晶界弓出形核的不连续动态再结晶为主,而在应变速率较高时,主要发生位错转动合并形成新的大角晶界的连续动态再结晶。

关键词： Cu-Ni-Si合金热压缩本构方程热加工图显微组织

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时效态C17200合金的组织与性能

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中国有色金属学报 2013年第6期23卷 1516-1522页

作者：彭丽军熊柏青解国良洪松柏解浩峰北京有色金属研究总院有色金属材料制备加工国家重点实验室北京100088 鹰潭兴业电子金属材料有限公司鹰潭335000

采用X射线衍射(XRD)、透射电子显微镜(TEM)、高分辨电子显微镜(HRTEM)等分析手段研究C17200合金时效过程中微观组织演变,测试不同时效工艺处理后合金的硬度和电导率等性能。结果表明:合金经320℃时效1 h后,基体(200)主峰的左侧出现比较... 详细信息

采用X射线衍射(XRD)、透射电子显微镜(TEM)、高分辨电子显微镜(HRTEM)等分析手段研究C17200合金时效过程中微观组织演变,测试不同时效工艺处理后合金的硬度和电导率等性能。结果表明:合金经320℃时效1 h后,基体(200)主峰的左侧出现比较明显的低角度边带峰,即合金发生调幅分解,使得在基体的(100)面上形成圆盘状结构的GP区。合金在时效过程中存在两种析出方式:晶界不连续析出和晶内连续析出,且连续析出序列为α过饱和固溶体→GP区→γ′→γ。调幅分解和γ′相析出是C17200合金在时效过程中硬度升高并达到峰值的主要原因。

关键词： C17200合金时效处理调幅分解微观组织

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不同处理工艺对Cu-Ni-Co-Si合金组织与性能的影响

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稀有金属材料与工程 2019年第6期48卷 1969-1974页

作者：彭丽军马吉苗刘兴宇刘峰黄国杰洪松柏解浩峰刘冬梅宁波兴业盛泰集团有限公司浙江宁波315336 北京有色金属研究总院有色金属材料制备加工国家重点实验室北京100088 北京有色金属研究总院生物冶金国家重点实验室北京100088

通过物理性能测试和扫描电子显微镜(SEM)、透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)等分析技术,系统研究不同处理工艺对Cu-Ni-Co-Si合金微观组织与性能的影响。结果表明,合金经热轧在线淬火时效处理后,合金中存在大量的正交... 详细信息

通过物理性能测试和扫描电子显微镜(SEM)、透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)等分析技术,系统研究不同处理工艺对Cu-Ni-Co-Si合金微观组织与性能的影响。结果表明,合金经热轧在线淬火时效处理后,合金中存在大量的正交结构的大颗粒(Ni,Co)2Si相和少量、细小的(Ni,Co)2Si相,是导致合金综合性能无法满足后续使用的主要原因;经固溶时效和固溶冷变形时效处理后,合金的硬度与时效时间的关系曲线均呈单峰型,而合金的导电率与时效时间的关系曲线均呈先快速增加后缓慢增大最后趋于稳定的趋势;综合性能优良的Cu-Ni-Co-Si合金合理的加工热处理制度为热轧试样经1000℃固溶处理1 h+60%冷变形+500℃时效2 h。合金经固溶时效和固溶冷变形时效处理后,基体中出现大量圆盘状的正交结构的(Ni,Co)2Si相,与基体的取向关系为(221)p//(200)Cu,(102)p//(001)Cu。

关键词： Cu-Ni-Co-Si合金固溶时效微观组织维氏硬度导电率

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A fiber-reinforced solid polymer electrolyte by in situ polymerization for stable lithium metal batteries

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Nano Research 2023年第7期16卷 9259-9266页

作者： Yifan Xu Ruo Zhao Lei Gao Tingsong Gao Wenjuan Wang Juncao Bian songbai Han Jinlong Zhu Qiang Xu Yusheng Zhao Institute for Advanced Study Shenzhen UniversityShenzhen 518055China Guangdong Provincial Key Laboratory of Energy Materials for Electric Power Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and DevicesAcademy for Advanced Interdisciplinary StudiesSouthern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials Department of Materials Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Peking UniversityBeijing 100871China

Solid polymer electrolytes(SPEs)by in situ polymerization are attractive due to their good interfacial contact with electrodes.Previously reported in situ polymerized SPEs,however,suffer from the low polymerization degree that causes poor mechanical strength,Li dendrite penetration,and performance decay in Li-metal batteries.Although highly polymerized SPEs are more stable than lowly polymerized ones,they are restricted by their sluggish long-chain mobility and poor ionic conductivity.In this work,a three-dimensional fibrous membrane with ion selectivity was prepared and used as a functional filler for the in situ formed SPE.The obtained SPE has high stability due to its high polymerization degree after the long-term heating process.The fibrous membrane plays a vital role in improving the SPE’s properties.The rich anion-adsorption sites on the fibrous membrane can alleviate the polarization effect and benefit a uniform current distribution at the interface.The fibrous nanostructure can efficiently interact with the polymeric matrix,providing rich hopping sites for fast Li+migration.Consequently,the obtained SPE enables a uniform Li deposition and long-term cycling performance in Li-metal batteries.This work reported an in situ formed SPE with both high polymerization degree and ionic conductivity,paving the way for designing high-performance SPEs with good comprehensive properties.

关键词： solid polymer electrolytes fibrous solid filler metal-organic frameworks in situ polymerization ion selectivity

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Effects of fluorination on crystal structure and electrochemical performance of antiperovskite solid electrolytes

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Journal of Energy Chemistry 2023年第2期77卷 521-528,I0013页

作者： Lei Gao Manrong Song Ruo Zhao songbai Han Jinlong Zhu Wei Xia Juncao Bian Liping Wang Song Gao Yonggang Wang Ruqiang Zou Yusheng Zhao School of Materials Science and Engineering Peking UniversityBeijing 100871China Guangdong Provincial Key Laboratory of Energy Materials for Electric Power Guangdong-Hong Kong-Macao Joint Laboratory for Photonic-Thermal-Electrical Energy Materials and DevicesAcademy for Advanced Interdisciplinary StudiesSouthern University of Science and TechnologyShenzhen 518055GuangdongChina Institute for Advanced Study Shenzhen UniversityShenzhen 518055GuangdongChina

The development of all-solid-state lithium batteries(ASSLBs)depends on exploiting solid-state electrolytes(SSEs)with high ionic conductivity and electrochemical stability.Fluorination is generally considered to be an effective strategy to improve the ionic conductivity and electrochemical stability of inorganic SSEs.Here,we report the partial fluorination of the chlo rine sites in an antiperovskite,by which the orthorhombic Li_(2)OHCl was transformed into cubic Li_(2)OHCl_(0.9)F_(0.1),resulting in a fourfold increase in ionic conductivity at 30℃.The ab initio molecular dynamics simulations suggest that both the crystal symmetry and the anions electronegativity influence the diffusion of Li+in the antiperovskite structure.Besides,from the perspective of experiments and calculations,it is confirmed that fluorination is a feasible method to improve the electrochemical stability of antiperovskite SSEs.The LiFePO_(4)|Li cell based on Li_(2)OHCl_(0.9)F_(0.1) is also assembled and exhibits stable cycle performance,which indicates that fluorination of antiperovskite SSEs is an effective way to produce high-performance SSEs for practical application of ASSLBs.

关键词： Antiperovskite Solid-state electrolyte Fluorination Ionic conductivity

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C17510弹性合金的固溶时效与组织性能的研究

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有色金属科学与工程 2014年第5期5卷 45-48,73页

作者：黄国杰洪松柏郑国辉赵洋汪东亚彭丽军北京有色金属研究总院有色金属材料制备加工国家重点实验室北京100088 鹰潭兴业电子金属材料有限公司江西鹰潭335000 宁波兴业盛泰集团有限公司浙江宁波315336

采用OM、SEM、XRD和TEM分析手段对C17510合金的固溶时效与组织性能进行研究.结果表明,冷轧态C17510合金的合理固溶处理温度为950℃.时效态C17510合金的硬度与时间呈单峰型曲线,合金的电导率与时间呈先剧增,后缓慢增大,最后趋于稳定的趋... 详细信息

采用OM、SEM、XRD和TEM分析手段对C17510合金的固溶时效与组织性能进行研究.结果表明,冷轧态C17510合金的合理固溶处理温度为950℃.时效态C17510合金的硬度与时间呈单峰型曲线,合金的电导率与时间呈先剧增,后缓慢增大,最后趋于稳定的趋势.冷轧态C17510合金经950℃×0.5 h固溶处理+525℃×4 h时效处理后,其维氏硬度为231,电导率为56%IACS.

关键词： C17510合金固溶时效处理微观组织维氏硬度电导率

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Effect of traditional Chinese medicinal enemas on ulcerative colitis of rats

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World Journal of Gastroenterology 2004年第13期10卷 1914-1917页

作者： Song-MingGuo hong-BinTong Lian-songbai WeiYang DepartmentofTraditionalChineseMedicine TongjiHospitalTongjiUniversityShanghai200065China DepartmentofTraditionalChineseMedicine ShuguangHospitalShanghaiTraditionalChineseMedicineUniversityShanghai200032China

AIM: To investigate the effects of traditional Chine semedicinal enema (TCME) on inflammatory and immune response of colonic mucosa of rats with ulcerative colitis(UC), and to observe the pathogenic mechanism.METHODS: Thirty UC rats, induced by intestinal enema together with 2.4-dinitrochlorobenzene (DNCB) and acetic acid, were randomly divided into 3 groups, i.e., GⅠ, GⅡ and GⅢ. Groups GⅠ and GⅡ were administered with TCME and salazosulfapyridine enema (SASPE), respectively. Group GⅢ was clystered with only normal saline (NSE), served as control. Group GIV was taken from normal rats as reference,once daily, from the 7th day after the establishment of UC for total 28 d. Interleukin-6 (IL-6) in the colonic mucosa was assayed by ^3H-TdR incorporation assay. Colonic mucosal lymphocyte subpopulation adhesive molecules, CD4^+CD11a^+,CD4^+CD18^+, CDs^+CD11a^+, CDs^+CD18^+ (LSAM), tumor necrosis factor (TNF)-α, and interferon-γ (IFN-γ), were detected by enzyme linked immunosorbent assay (ELISA). Moreover, the expression of TNF-α mRNA and IFN-γ mRNA in colonicmuc osa were detected by polymerase chain reaction (RT-PCR).RESULTS: Before therapies, in model groups, GⅠ, GⅡ and GⅢ,levels of IL-6, TNF-α, IFN-γ, CDs^+CD11a^+ and CD8^+CD18^+ were significantly different (38.29+2.61 U/mL, 16.54+1.23 ng/L,8.61+0.89 ng/L, 13.51+2.31% and 12.22+1.13% ,respectively) compared to those in GIV group (31.56+2.47 U/mL, 12.81+1.38 ng/L, 5.28+0.56 ng/L, 16.68+1.41% and 16.79+1.11%, respectively). After therapeutic enemas,in GI group, the contents of IL-6 (32.48±2.53 U/m), TNF-α(13.42±1.57 ng/L) and IFN-γ (5.87+0.84 ng/L) were reduced; then, the contents of CD8^+CD11a^+ (16.01+1.05 %)and CD8^+CD18^+ (16.28±0.19%) were raised. There was no significant difference between groups GⅠ and GIV, but the difference between groups GⅠ and GⅡ was quite obvious (P<0.05). The expressions of TNF-α mRNA and IFN-γ mRNAin group GⅢ were much higher than those of group GIV,but those in group GI were significantly suppressed by TCME therapy.CONCLUSION: Ulcerative

关键词：传统中医药灌肠剂溃疡性结肠炎老鼠免疫反应

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6063铝合金氧化膜与CsF-AlF_3及KF-AlF_3钎剂的反应机制

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焊接学报 2009年第9期30卷 13-16,20页

作者：朱宏薛松柏盛重南京航空航天大学材料科学与技术学院南京210016 中国电子科技集团第十四研究所南京210013

选用CsF-AlF3和KF-AlF3钎剂,研究了两种钎剂在6063铝合金表面不同温度下的去膜效果,并分析和探讨了钎剂与6063铝合金表面氧化膜的反应机制.研究发现,CsF-AlF3钎剂是以反应、溶解的机制去除6063铝合金表面氧化膜的,NH4F在高温下生成的HF... 详细信息

选用CsF-AlF3和KF-AlF3钎剂,研究了两种钎剂在6063铝合金表面不同温度下的去膜效果,并分析和探讨了钎剂与6063铝合金表面氧化膜的反应机制.研究发现,CsF-AlF3钎剂是以反应、溶解的机制去除6063铝合金表面氧化膜的,NH4F在高温下生成的HF是CsF-AlF3钎剂去膜的关键化合物.此外,H2O的存在或形成促进了HF的生成,从而加速了钎剂的去膜进程.CsF-AlF3钎剂反应产物中没有发现CsF和AlF3,只有少量的CsAlF4存在.在570℃下,KF-AlF3钎剂反应产物中以KAlF4为主,而在610℃条件下,KAlF4已不存在,只有少量的KMgF3生成.结果表明,在610℃条件下,Mg,Mn元素和KAlF4将逐渐地消耗掉,使得钎剂熔点急剧升高,导致钎剂流动性变差.

关键词： 6063铝合金氧化膜钎剂反应产物

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