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气候变化对黄河河源区水资源系统的影响

干旱区资源与环境 2006年第6期20卷 57-62页

作者：蓝永超沈永平李州英刘进琪马建华中国科学院寒区旱区环境与工程研究所兰州730000 黄河水利委员会上游水文水资源局兰州730000

利用水文、气象台站观测资料,分析了黄河河源区近几十年来温度、降水的变化。结果显示,该区域的温度对全球变暖有着明显的对应关系,近几十年来流域各个地方的温度有着不同程度的上升。降水量总体上呈减少态势,但因地理位置的不同而差异... 详细信息

利用水文、气象台站观测资料,分析了黄河河源区近几十年来温度、降水的变化。结果显示,该区域的温度对全球变暖有着明显的对应关系,近几十年来流域各个地方的温度有着不同程度的上升。降水量总体上呈减少态势,但因地理位置的不同而差异较大。其中,位于流域产流高值区的东南部近10余年降水大幅减少,受其影响,黄河源区产水量呈持续递减的态势。基于上述分析,利用大气环流模型(GCMS)与统计模式对未来流域气温、降水和径流的可能变化进行了预测,计算结果均表明,未来30年里黄河河源区的温度将进一步上升,并且降水量也有显著增加。受其影响,黄河河源区径流量将比1990S有显著增加。

关键词：黄河河源区全球变暖大气环流模型

Salt-assisted vapor-liquid-solid growth of high-quality ultrathin nickel oxide flakes for artificial synapses in image recognition applications

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Nano Research 2024年第5期17卷 4622-4630页

作者： Hui Zhang Zongjie shen Alei Li Lin Wang Qinan Wang Yunfei Li Yunlei Zhong Juntong Zhu yong Zhang Mengjiao Han Dan Tian Chun Zhao Lixing Kang Qingwen Li School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China Division of Advanced Materials Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China College of Energy Soochow Institute for Energy and Materials Innovationsand Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou 215123China Songshan Lake Materials Laboratory Dongguan 523808China School of Advanced Technology Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesNanjing Forestry UniversityNanjing 210037China

Transition metal oxides have attracted intense interest owing to their abundant physical and chemical *** controlled preparation of large-area,high-quality two-dimensional crystals is essential for revealing their inherent properties and realizing high-performance ***,fabricating two-dimensional(2D)transition metal oxides using a general approach still presents substantial ***,we successfully achieve highly crystalline nickel oxide(NiO)flakes with a thickness as thin as 3.3 nm through the salt-assisted vapor-liquid-solid(VLS)growth method,which demonstrated exceptional stability under ambient *** explore the great potential of the NiO crystal in this work,an artificial synapse based on the NiO-flake resistive switching(RS)layer is ***-term and long-term synaptic behaviors are obtained with external *** artificial synaptic performance provides the foundation of the neuromorphic application,including handwriting number recognition based on artificial neuron network(ANN)and the virtually unsupervised learning capability based on generative adversarial network(GAN).This pioneering work not only paves new paths for the synthesis of 2D oxides in the future but also demonstrates the substantial potential of oxides in the field of neuromorphic computing.

关键词： nickel oxide(NiO)flakes vapor-liquid-solid(VLS)growth memristor synapse generative adversarial network(GAN)

Function-reversible facets enabling SrTiO_(3)nanocrystals for improved photocatalytic hydrogen evolution

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Frontiers in Energy 2024年第1期18卷 101-109页

作者： Bin WANG Bei AN Xiaoqian LI Shaohua shen School of Physics Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter(Ministry of Education)Key Laboratory of Shaanxi for Advanced Materials and Mesoscopic PhysicsXi’an Jiaotong UniversityXi’an 710049China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China

It has been widely reported that,for faceted nanocrystals,the two adjacent facets with different band levels contribute to promoted charge separation,and provide active sites for photocatalytic reduction and oxidation reaction,*** such cases,only one family of facets can be used for photocatalytic hydrogen ***,by using SrTiO_(3)nanocrystals enclosed by{023}and{001}facets as a model photocatalyst,this paper proposed a strategy to achieve the full-facets-utilization of the nanocrystals for photocatalytic hydrogen via chemically depositing Pt nanoparticles on all *** photo-deposition experiment of CdS provided direct evidence to demonstrate that the{023}facets which were responsible for photooxidation reaction can be function-reversed for photocatalytic hydrogen evolution after depositing Pt nanoparticles,together with the{001}***,the full-facets-utilization led to a much-improved activity for photocatalytic hydrogen,in contrast to those SrTiO_(3)nanocrystals with only{001}facets deposited by Pt nanoparticles via a photo-deposition method.

关键词： SrTiO_(3)nanocrystals crystal facets photocatalysis hydrogen evolution

A Systematic Analysis of Early Life Exposure to the Chinese Famine(1959-1961)and the Health of Older Adults-China,2008-2023

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China CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： Chi shen Xi Chen School of Public Policy and Administration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Department of Health Policy and Management Yale School of Public HealthNew HavenCTU.S Department of Economics Yale UniversityNew HavenCTU.S

What is already known about this topic?There is mounting evidence indicating that the aging process initiates during early life stages,with in utero the individual’s environment playing a significant ***,it is crucial to comprehend the enduring effects of early life circumstances on health in old *** is added by this report?In this study,we conducted a meta-analysis to examine the effects of the Chinese Famine(1959–1961)on the health of older *** also explored potential mechanisms underlying these *** are the implications for public health practice?The complex interplay between early life circumstances,multiple health-related sectors,and healthy aging necessitates a comprehensive life-course approach and strategic interventions to enhance public health in an aging society.

关键词： life aging mount

Investigation of Ce/BEA as a passive NO_(x)adsorber:*** occurrences of cerium and adsorption behavior

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Journal of Rare Earths 2024年第7期42卷 1265-1271,I0003页

作者： Minghui Yu Yiying Ding Xiaojie Yu Siwei Yan Meiqing shen Jianqiang Wang Jun Wang Gurong shen School of Materials Science and Engineering Tianjin UniversityTianjin300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin300350China National Rare Earth Catalysis Research Institute Dongying257000China

Ce/BEA has great potential as a passive NO_(x)absorber(PNA)to reduce the NO_(x)emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NO_(x)desorption temperature ***,as a novel material,its physical and chemical properties still remain *** this work,Ce/BEA was synthesized by ion-exchange method to identify the active species in NO_(x)adsorption,compared with aggregated Ce species in Ce/SiAlO_(x) prepared by impregnation method.X-ray diffraction(XRD),high resolution-transmission electron microscopy(HR-TEM)and aberration-corrected-scanning transmission electron microscopy(AC-STEM)were performed to confirm the isolated single atom formation of Ce species in Ce/***-vis diffraction reflection spectra(DRS)and X-ray photoelectron spectroscopy(XPS)were conducted to find the difference of chemical environment between the isolated Ce species and aggregated *** performance evaluation and temperature programmed reduction of hydrogen(H_(2)-TPR)results show the high NO_(x)storage capacity and active oxygen species quantity in Ce/*** is also found that the main NO_(x)adsorption species are Ce^(4+)-O^(∗)rather than Ce^(3+).NO_(x)-diffuse reflectance infrared Fourier transform spectroscopy(NO_(x)-DRIFTS)confirms that the bidentate nitrite species are the critical NO_(x)adsorption intermediates and the conception of NO_(x)adsorption and desorption processes is proposed.

关键词： Passive NO_(x)absorber Ce/BEA Isolated Ce species Rare earths

1979-2009年《冰川冻土》论文发表趋势:基于文献计量分析的结果与启示

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冰川冻土 2010年第6期32卷 1276-1285页

作者：宁宝英何元庆沈永平梁红中国科学院国家科学图书馆兰州分馆甘肃兰州730000 中国科学院资源环境科学信息中心甘肃兰州730000 中国科学院寒区旱区环境与工程研究所甘肃兰州730000

利用数据库提供的文献详细信息,从文献计量分析的角度,基于对1979-2009年《冰川冻土》刊载论文的数量、学科分类、研究地域、核心作者群、研究热点等指标的年际分布量化,分析了该刊所关注的研究内容与研究方向变化,探讨了国内从事该领... 详细信息

利用数据库提供的文献详细信息,从文献计量分析的角度,基于对1979-2009年《冰川冻土》刊载论文的数量、学科分类、研究地域、核心作者群、研究热点等指标的年际分布量化,分析了该刊所关注的研究内容与研究方向变化,探讨了国内从事该领域研究的组织机构分布与研究人员组成的区域变化.结果表明,31 a来《冰川冻土》的论文发表数量总体呈波动性快速增长趋势,中国科学院实施知识创新工程以来,这种增长尤为明显;相关研究机构具有明显的地域相关性,主要集中冰川冻土分布区周边,近来东部地区的部分综合性院校的加入表明国内对冰川、冻土及相关问题的关注度日益增强;冰川地貌、多年冻土、气候变化、青藏高原和青藏铁路为该刊出现频次最高的5个关键词,其中气候变化作为最高频年度关键词出现11次,反映了《冰川冻土》关注的研究热点.《冰川冻土》刊载的论文被CSCD和SCI引用频次和期刊影响因子不断提高,说明了学界对冰川、冻土及相关问题的关注程度不断加强.另外,由于新兴研究力量的兴起和研究者提高国际影响力的需求,导致该刊尚未形成核心作者群,这对未来我国冰川冻土研究成果的国际推介和期刊的发展方向提出了新的机遇与挑战.

关键词：《冰川冻土》文献计量分析发表趋势

Ultrafine ordered L1_(2)-Pt-Co-Mn ternary intermetallic nanoparticles as high-performance oxygen-reduction electrocatalysts for practical fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 157-165,I0005页

作者： Enping Wang Liuxuan Luo yong Feng Aiming Wu Huiyuan Li Xiashuang Luo Yangge Guo Zehao Tan Fengjuan Zhu Xiaohui Yan Qi Kang Zechao Zhuang Daihui Yang Shuiyun shen Junliang Zhang China-UK Low Carbon College Shanghai Jiao Tong UniversityShanghai 201306China Institute of Fuel Cells Key Laboratory for Power Machinery and Engineering of MOESchool of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Tangfeng Energy Technology Co.Ltd. Shanghai 201306China State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China Department of Chemical Engineering Columbia UniversityNY 10027USA

The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy ***,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/***,it also has a greatly enhanced electrochemical *** addition,the effects of annealing temperature and time are further *** importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel *** characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering *** work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.

关键词： Platinum Cobalt Manganese Oxygen reduction reaction Ordered intermetallic L1_(2)atomic structure Proton-exchange membrane fuel cell

贡嘎山海螺沟冰川物质平衡、水交换特征及其对径流的影响

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冰川冻土 2001年第1期23卷 7-15页

作者：谢自楚苏珍沈永平冯清华湖南师范大学资源与环境研究所湖南长沙410081 中国科学院寒区旱区环境与工程研究所甘肃兰州730000

在贡嘎山海螺沟冰川研究的基础上 ,提出计算该冰川物质平衡的两种方法 ,获得了较一致的结果 .表明近 10a来物质平衡平均为 - 470mm ,与高亚洲边缘山脉的冰川同样处于强烈的衰退状态 .该冰川有很高的物质平衡水平 (2 5 44mm)及水交换水平... 详细信息

在贡嘎山海螺沟冰川研究的基础上 ,提出计算该冰川物质平衡的两种方法 ,获得了较一致的结果 .表明近 10a来物质平衡平均为 - 470mm ,与高亚洲边缘山脉的冰川同样处于强烈的衰退状态 .该冰川有很高的物质平衡水平 (2 5 44mm)及水交换水平 (3 819mm) ,液相比例高 (1/3) ,较小的稳定性系数 (0 2 0 ) ,具有典型的季风海洋型冰川的水交换特征 .由于冰川退缩冰川径流增加 ,预计 2 0 2 0年将达到临界状态 .在气候持续转暖变湿情况下 ,预测临界状态将延至 2 0 5 0年左右。

关键词：海螺沟冰川物质平衡水分交换径流变化最大熵法

乌鲁木齐河源区44a来气候变暖特征及其对冰川的影响

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冰川冻土 2005年第6期27卷 813-819页

作者：王国亚沈永平毛炜峄中国科学院寒区旱区环境与工程研究所甘肃兰州730000 中国气象局乌鲁木齐沙漠气象研究所新疆乌鲁木齐830002

应用乌鲁木齐河源区大西沟气象站1961—2004年44 a逐日气象观测资料,从最高、最低气温、日较差及积温变化角度分析了河源区的气候变暖特征.结果表明:最低、最高、年平均气温、冬季极端最低气温均呈升高趋势,并且最低气温的上升幅度大于... 详细信息

应用乌鲁木齐河源区大西沟气象站1961—2004年44 a逐日气象观测资料,从最高、最低气温、日较差及积温变化角度分析了河源区的气候变暖特征.结果表明:最低、最高、年平均气温、冬季极端最低气温均呈升高趋势,并且最低气温的上升幅度大于最高气温的上升幅度,呈非对称性变化;气温日较差有显著变小的趋势;日照时数有变少的趋势,可能与大气中水汽含量的增加、云量增多有关,显示了大气水汽温室效应在气候变暖过程中的重要作用.河源区云量出现主要在下午到晚上,其增多显示的水汽温室效应使最低温上升明显,进而对冰川的消融和冰川冰的增温产生影响.计算了稳定通过T≥0℃的气候积温,其与冰川物质平衡相关性最大.最后讨论了积温变化趋势与1号冰川物质平衡的关系以及冰川对气候变化的敏感性.

关键词：气候变暖气候积温冰川响应敏感性乌鲁木齐河源