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Chinese Journal of Chemical Physics 2017年第4期30卷 372-378,I0001页

作者：刘舒婷苏涛张鹏费泽杰刘洪涛中国科学院上海应用物理研究所熔盐化学与工程技术部上海201800

On account of excellent thermal physical properties, molten nitrates/nitrites salt has been widely employed in heat transfer and thermal storage industry, especially in concentrated solar power system. The thermal stability study of molten nitrate/nitrite salt is of great importance for this system, and the decomposition mechanism is the most complicated part of it. The oxide species O2^2- and O2^- were considered as intermediates in molten KNO3-NaNO3 while hard to been detected in high temperature molten salt due to their trace concentration and low stability. In this work, the homemade in situ high temperature UV- Vis instrument and a commercial electron paramagnetic resonance were utilized to supply evidence for the formation of superoxide during a slow decomposition process of heat transfer salt （HTS, 53 wt% KNO3/40 wt% NaNO2/7 wt% NaNO3）. It is found that the superoxide is more easily generated from molten NaNO2 compared to NaNO3, and it has an absorption band at 420-440 nm in HTS which red shifts as temperature increases. The band is assigned to charge-transfer transition in NaO2 or KO2, responsible for the yellow color of the molten nitrate/nitrite salt. Furthermore, the UV absorption bands of molten NaNO2 and NANO3 are also obtained and compared with that of HTS.

关键词： Superoxide Decomposition of heat transfer salt High temperature UV-visible Electron paramagnetic resonance

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW China

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Science China Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3,4, ZHANG Hucai2, WANG Weiguo3 & AN Chenbang3 1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 2. Nanjng Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China 3. Environment and Resources College, Lanzhou University, Lanzhou 730000, China 4. Beijing Normal University, Beijing 100875, China 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal University Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Synthesis of aminoalkylsilanes with oligo(ethylene oxide) unit as multifunctional electrolyte additives for lithium-ion batteries

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Science China Chemistry 2013年第6期56卷 739-745页

作者： WANG JingLun LUO Hao MAI YongJin ZHAO XinYue ZHANG LingZhi Guangzhou Institute of Energy Conversion Chinese Academy of Sciences

Aminoalkylsilanes with oligo(ethylene oxide) units were designed and synthesized as multifunctional electrolyte additives for lithium-ion batteries. The chemical structures were fully characterized by nuclear magnetic resonance (NMR) spectroscopy and their thermal properties, viscosities, electrochemical windows, and ionic conductivities were systematically measured. With adding one of these compounds (1 vol. %, DSC3N1) in the baseline electrolyte 1.0 M LiPF 6 in EC: DEC (1:1, in volume), Li/LiCoO 2 half cell tests showed an improved cyclability after 100 cycles and improved rate capability at 5C rate condition. Electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), and energy dispersive spectroscopic (EDS) analysis confirmed the acid scavenging function and film forming capability of DSC3N1. These results demonstrated that the multifunctional organosilicon compounds have considerable potential as additives for use in lithium-ion batteries.

关键词： aminoalkylsilane electrolyte additives lithium cobalt oxide lithium-ion batteries

Hierarchically porous carbon/red phosphorus composite for high-capacity sodium-ion battery anode

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Science Bulletin 2018年第15期63卷 982-989页

作者： Meng Li Na Feng Mengmeng Liu Zifeng Cong Jiangman Sun Chunhua Du Quanbin Liu Xiong Pu Weiguo Hu cas Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and Sensor Beijing Institute of Nanoenergy and NanosystemsChinese Academy of Sciences School of Nannoscience and Technology University of Chinese Academy of Sciences School of Chemical Engineering and Light Industry Guangdong University of Technology Center on Nanoernergy Researh School of Physical Science and Technology Guangxi University

Red phosphorus has received remarkable attention as a promising anode material for sodium ion batteries(NIBs) due to its high theoretical capacity. However, its practical application has been impeded by its intrinsic low electronic conductivity and large volume variations during sodiation/desodiation process. Here, we design a composite to confine nanosized red phosphorus into the hierarchically porous carbon(HPC) walls by a vaporization-condensation strategy. The mass loading of P in the HPC/P composite is optimized to deliver a reversible specific capacity of 2,202 m Ah/gpbased on the mass of red P(836 m Ah/gcompositebased on the total composite mass), a high capacity retention over 77% after100 cycles, and excellent rate performance of 929 m Ah/gpat 2 C. The hierarchical porous carbon serves as the conductive networks, downsize the red phosphorus to nanoscale, and provide free space to accommodate the large volume expansions. The suppressed mechanical failure of the red phosphorus also enhances the stability of solid-electrolyte interface(SEI) layer, which is confirmed by the microscopy and impedance spectroscopy after the cycling tests. Our studies provide a feasible approach for potentially viable high-capacity NIB anode.

关键词： Red phosphorus Hierarchical porous carbon Sodium ion batteries Anode

Environmental impacts of domestic resource extraction in China

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Ecosystem Health and Sustainability 2019年第1期5卷 67-78,I0013页

作者： Shen Zhao He-Ming Wang Wei-Qiang Chen Dong Yang Jing-Ru Liu Feng Shi State Environmental Protection Key Laboratory of Eco-Industry Northeastern UniversityShenyangChina Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of ScienceXiamenFujianChina Xiamen Key Lab of Urban Metabolism XiamenFujianChina SDAS Key Laboratory of Scientific Decision-Making Institute of Science and Technology for Development of ShandongQilu University of Technology(Shandong Academy of Sciences)JinanChina Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijingChina

Introduction:The rapid development of economy has led to extensive raw material consumption and relevant environmental damage in *** analyze environmental impacts and identify materials resulting in these environmental effects via raw material extraction,we combine economy-wide material flow accounting and life-cycle analysis methods to estimate environmental impacts of Chinese domestic extraction(DE)during the period of 1992–*** relationship between these increasing environmental impacts and Chinese GDP was also explored by decoupling ***:Results show that Chinese DE increased by 372%during 1992–*** global warming potential,abiotic depletion potential,and respiratory inorganics of Chinese DE increased by 195%,46%,and 408%,*** terms of specific materials,extraction of iron ores,gravel and sand,and coal induced the most environmental *** relationship between environmental impacts and Chinese GDP/DE was characterized by relative ***:To minimize the environmental impacts of extraction,we recommend that the Chinese government improve its extraction techniques and reduce excess demand for materials with large extraction such as iron ores,gravel and sand,and *** also recommend researching alternative materials for scarce resources like molybdenum,gold,and fluorite.

关键词： Decoupling analysis economy-wide material flow accounting life cycle assessment environmental impact material flows

Quantum Confinement Effects in Dynamically Screened Quasi-One-DimensionalSystems

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Chinese Physics Letters 2013年第6期30卷 178-181页

作者： WANG Ting-Dong HUAI Ping Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800 University of Chinese Academy of Sciences Beijing 100049

We theoretically study the quantum confinement effects on the self-energies of electrons and holes in quasi-onedimensional semiconductor *** is found that the effective Coulomb interactions are enhanced with the increase in lateral confinement and the decrease in confinement *** single-particle self-energies of electrons and holes are calculated in dynamic plasmon pole approximation within the GW approximation,where G refers to Green’s function and W is the dynamically screened Coulomb *** real and imaginary parts of the self-energies have a strong dependence on the effective Coulomb interactions.

关键词： interaction. approximation imaginary

Frequency dependence in the emission from subpulse drifting pulsars

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Research in Astronomy and Astrophysics 2021年第9期21卷 153-162页

作者： Xiao-Hong Han Rai Yuen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesUrumqi 830011China SIfA School of PhysicsUniversity of SydneySydneyNSW 2006Australia

We investigate relations in the emission properties as revealed by drifting subpulses detected at different observing frequencies based on the method that incorporates the rotating carousels in pulsar magnetospheres of multiple emission *** emission state is associated with particular emission properties as determined by the drifting subpulses at a particular frequency,and different emission states obtained at different frequencies reveal the variation of emission properties across the emission *** method allows the determination of the essential radio emission properties such as the relative emission height,subpulse number,charge density and the plasma flow relative to corotation in an emission region for a particular *** apply the method to seven pulsars that exhibit subpulse drifting along single drift-band at 326 MHz and 1429 *** results show that drifting subpulses observed at different frequencies correspond to particular emission states suggesting that the pulsar emission properties are frequency *** show that emission follows the frequency-to-radius mapping for pulsars with obliquity angle?30°regardless of the sign and magnitude of the *** pulsars with long rotation periods in our sample,the circulation time for the plasma to revolve once around the magnetosphere relative to corotation increases as the rotation period increases at both frequencies,but exhibits irregularity for pulsars with short rotation *** results suggest that evolution of the obliquity angles in subpulse drifting pulsars is from large to small,and the emission region tends to be’thicker’in younger pulsars.

关键词： radiation mechanisms:non-thermal pulsar:general

Expansion and expression diversity of FAR1/FRS-like genes provides insights into flowering time regulation in roses

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Plant Diversity 2021年第2期43卷 173-179页

作者： Mi-Cai Zhong Xiao-Dong Jiang Wei-Hua Cui Jin-Yong Hu cas Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China

Roses are important horticultural plants with enormous diversity in flowers and flowering ***,molecular regulation of flowering time variation in roses remains poorly ***,we report an expansion of the FAR1/FRS-like genes that correlates well with the switch to prostrate-toerect growth of shoots upon flowering in Rosa wichuraiana‘Basye's Thornless'(BT).With the availability of the high-quality chromosome-level genome assembly for BT that we developed recently,we identified 91 RwFAR1/FRS-like genes,a significant expansion in contrast to 52 in Rosa chinensis‘Old Blush’(OB),a founder genotype in modern rose *** FAR1/FRS-like proteins feature distinct variation in protein domain *** dispersed expansion of RwFAR1/FRS-like genes occurred specifically in clade I and II and is significantly associated with transposon insertion in *** of the RwFAR1/FRS-like genes showed relatively higher expression level than their corresponding orthologs in ***1/FRS-like genes regulate light-signaling processes,shade avoidance,and flowering time in Arabidopsis ***,the expansion and duplication of RwFAR1/FRS-like genes,followed by diversification in gene expression,might offer a novel leverage point for further understanding the molecular regulation of the variation in shoot-growth behavior and flowering time in roses.

关键词： Rose FAR1/FRS-Like genes Gene family expansion Flowering time Shoot growth behavior

Land cover mapping toward finer scales

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Science Bulletin 2020年第19期65卷 1604-1606页

作者： Min Feng Xin Li National Tibetan Plateau Data Center Key Laboratory of Tibetan Environmental Changes and Land Surface ProcessesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China University of Chinese Academy Sciences Beijing 100049China

Land cover is the physical evidence on Earth,and land cover maps show the spatial distribution of the different covers on the Earth’s surface as well as the complex interactions among *** evolving for several decades,land cover mapping has reached a milestone and is currently experiencing a transformation from coarse and moderate scales to much finer scales to provide more precise knowledge on *** paper reviews the history of land cover mapping,summarizes the key characteristics of this transformation,and highlights the recent advances in urban land cover mapping.

关键词： Earth scales transformation

Robust enhanced hydrogen production at acidic conditions over molybdenum oxides-stabilized ultrafine palladium electrocatalysts

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Nano Research 2021年第1期14卷 268-274页

作者： Ji Sun Xian Zhang Meng Jin Qizhong Xiong Guozhong Wang Haimin Zhang Huijun Zhao Key Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in Nanoscience InstituteInstitute of Solid State PhysicsChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Centre for Clean Environment and Energy Griffith UniversityGold Coast CampusQLD 4222Australia

Electrochemical water splitting is quite seductive for eco-friendly hydrogen fuel energy production,however,the attainment of highly efficient,durable,and cheap catalysts for the hydrogen evolution reaction(HER)remains *** this study,molybdenum oxides stabilized palladium nanoparticle catalysts(MoO_(x)-Pd)are in situ prepared on commercial carbon cloth(CC)by the facile two-step method of dip-coating and electrochemical *** a self-supported Pd-based catalyst electrode,the MoO_(x)-Pd/CC presents a competitive Tafel slope of 45.75 mV·dec^(-1),an ultralow overpotential of 25 mV,and extremely long cycling durability(one week)in 0.5M H_(2)S0_(4)electrolyte,superior to unmodified Pd catalysts and comparable to commercial Pt mesh *** the one hand,the introduction of MoO_(x)can inhibit the growth of Pd particles to obtain ultrafine Pd nanoparticles,thus exposing more available active *** the other hand,density functional theory(DFT)calculation revealed that MoO_(x)on the surface of Pd metal can regulate the electronic structure of Pd metal and enhance its intrinsic catalytic activity of *** work suggests that transitional metal nanoparticles stabilized by molybdenum oxides are hopeful approaches for obtaining fruitful hydrogen-producing electrocatalysts.

关键词： MoO_(x) Pd nanoparticles electrocatalysts hydrogen evolution reaction