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Soil respiration in typical plant communities in the wetland surrounding the high-salinity Ebinur Lake

Frontiers of Earth Science 2018年第3期12卷 611-624页

作者： yanhong li Mingliang ZHAO Fadong li Xinjiang Normal University College of Geography and Tourism Urumqi 830054 China Key Laboratory of Xinjiang Uygur Autonomous Region Xinjiang Laboratory of Lake Environment and Resources in Arid Area Urumqi 830054 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100190 China

Soil respiration in wetlands surrounding lakes is a vital component of the soil carbon cycle in arid regions. However, information remains limited on the soil respiration around highly saline lakes during the plant growing season. Here, we aimed to evaluate diurnal and seasonal variation in soil respiration to elucidate the controlling factors in the wetland of Ebinur Lake, Xinjiang Uygur Autonomous Region, western China. We used a soil carbon flux automatic analyzer （li-840A） to measure soil respiration rates during the growing season （April to November） in two fields covered by reeds and tamarisk and one field with no vegetation （bare soil） from 2015 to 2016. The results showed a single peak in the diurnal pattern of soil respiration from 11：00 to 17：00 for plots covered in reeds, tamarisk, and bare soil, with minimum values being detected from 03：00 to 07：00. During the growing season, the soil respiration of reeds and tamarisk peaked during the thriving period （4.16 and 3.75 μmol.m-2.s-1, respectively）, while that of bare soil peaked during the intermediate growth period （0.74 pmol-m-2-s-1）. The soil respiration in all three plots was lowest during the wintering period （0.08, 0.09, and -0.87 μmol.m-2.s-1, respectively）. Air temperature and relative humidity significantly influenced soil respiration. A significant linear relationship was detected between soil respiration and soil temperature for reeds, tamarisk, and bare soil. The average Q10 of reeds and tamarisk were larger than that of bare soil. However, soil moisture content was not the main factor controlling soil respiration. Soil respiration was negatively correlated with soil pH and soil salinity in all three plot types. In contrast, soil respiration was positively correlated with organic carbon. Overall,CO2 emissions and greenhouse gases had a relatively weak effect on the wetlands surrounding the highly saline Ebinur Lake.

关键词： Ebinur Lake soil respiration high salinity soil temperature soil moisture

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Interaction Kinetics between Sn-Pb Solder Droplet and Au/Ni/Cu Pad

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Journal of Materials Science & Technology 2006年第3期22卷 392-396页

作者： Fuquan li Chunqing WANG yanhong TIAN Microjoining Lab. School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The interracial phenomena of the Sn-Pb solder droplet on and needle-like AuSn4 are formed at the interface after Au/Ni/Cu pad are investigated. A continuous AuSn2 the liquid state reaction （soldering）. The interracial reaction between the solder and Au layer continues during solid state aging with AuSn4 breaking off from the interface and felling into the solder. The kinetics of Au layer dissolution and diffusion into the solder during soldering and aging is analyzed to elucidate intermetallic formation mechanism at the solder/Au pad interface. The concentration of Au near the solder/pad interface is identified to increase and reach the solubility limit during the period of liquid state reaction. During solid state reaction, the thickening of Au-Sn compound is mainly controlled by element diffusion.

关键词： Sn-Pb solder droplet Intermetallic Aging Dissolution

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A class of Ga-Al-P-based compounds with disordered lattice as advanced anode materials for li-ion batteries

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Journal of Energy Chemistry 2023年第4期79卷 12-21页

作者： yanhong li Peixun Xiong Lei Zhang Songliu Yuan Wenwu li School of Physics Huazhong University of Science and TechnologyWuhan 430074HubeiChina School of Chemical Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon 440-746Republic of Korea School of Materials Science&Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Phosphides possess large reversible capacity, small voltage hysteresis, and high energy efficiency, thus promising to be new anode candidates to replace commercial graphite for li-ion batteries(liBs).Through a facile mechanochemistry method, we prepare a novel ternary phosphide of Ga0.5Al0.5P whose crystalline structure is determined to be a cation-disordered cubic zinc sulfide structure according to XRD refinement. As an anode for liBs, the Ga0.5Al0.5P delivers a reversible capacity of 1,352 mA h g^(-1)at100 mA g^(-1)with an initial Coulombic efficiency(ICE) up to 90.0% based on a reversible li-storage mechanism integrating intercalation and subsequent conversion processes as confirmed by various characterizations techniques including in-situ XRD, ex-situ Raman, and XPS and electrochemical ***-modified Ga0.5Al0.5P exhibits a long-lasting cycling stability of retaining 1,182 mA h g^(-1)after300 cycles at 100 m A g^(-1), and 625 mA h g^(-1)after 800 cycles at 2,000 mA g^(-1), and a high-rate performance of remaining 342 m A h g^(-1)at 20,000 mA g^(-1). The outstanding electrochemical performances can be attributed to enhanced reaction kinetics enabled by the capacitive behaviors and the faster liion diffusion enabled by the cation-mixing. Importantly, by tuning the cationic ratio, we develop a novel series of cation-mixed compounds of Ga_(1/3)Al_(2/3)P, Ga_(1/4)Al_(3/4)P, Ga_(1/5)Al_(4/5)P, Ga_(2/3)Al_(1/3)P, Ga_(3/4)Al_(1/4)P, and Ga_(4/5)Al_(1/5)P, which demonstrate large capacity, high ICE, and suitable anode potentials. Broadly, these compounds with disordered lattices probably present novel physicochemical properties, and high electrochemical performances, thus providing a new perspective for new materials design.

关键词： Multinary phosphides Disordered lattice Anode li-ion batteries

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Facile preparation of compact LTA molecular sieve membranes on polyethyleneimine modified substrates

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Chinese Chemical Letters 2021年第3期32卷 1086-1088页

作者： Fangge Chen yanhong li Aisheng Huang Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of ChemistryEast China Normal UniversityShanghai 200241China

A facile preparation strategy was proposed for preparation of compact zeolite LTA membranes on polyethyleneimine(PEI)modified substrates without *** the functionalization of substrates by using PEI,compact LTA membranes can be formed on various kinds of substrates.A well-intergrown and phase-pure LTA membrane with a thickness of about 3.0μm is successfully prepared on the a-Al_(2)O_(3)disk after crystallization for 24 h at 60℃.Besides LTA membrane,wellintergrown zeolite FAU membranes can also be formed on PEI-modified a-Al_(2)O_(3)substrates,suggesting the universality of this *** zeolite LTA membranes synthesized on PEI-modified a-Al_(2)O_(3)tubes were evaluated for the separation of alcohols/water mixture through *** as-synthesized zeolite LTA membranes display high pervaporation *** the separation of 10 wt%isopropanol/water solution at 90℃,a high separation factor of44991 and a water flux of 1.73 kg m^(-2)h^(-1)are achieved.

关键词： Zeolite LTA membrane Polyethyleneimine modification Covalent modification Alcohols/water separation Membrane separation

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Recent Progress of Counter Electrodes in Nanocrystalline Dye-sensitized Solar Cells

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Journal of Materials Science & Technology 2007年第5期23卷 577-582页

作者： Kexin li Zhexun YU yanhong LUO Dongmei li Qingbo MENG Beijing National Laboratory for Condensed Matter Phy~cs Institute of l~hysics Chinese Academy of Sciences Beijing100080 China

Dye-sensitized solar cell （DSC） consists a combination of several different materials： photoanodes with nanoparticulated semiconductors, sensitizers, electrolytes and counter electrodes （CEs）. Each materials performs specific task for the conversion of solar energy into electricity. The main function of CE is to transfer electrons to the redox electrolyte and regenerate iodide ion. The work of CE is mainly focused on the studies of the kinetic performance and stability of the traditional CEs to improve the overall efficiency of DSC, seeking novel design concepts or new materials. In this review, the development and research progress of different CE materials and their electrochemical performance, and the problems are discussed.

关键词： Counter electrode Dye-sensitized solar cell Carbon Polymer

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Multi-scale analysis of trade-off/synergistic effects of forest ecosystem services in the Funiu Mountain Region,China

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Journal of Geographical Sciences 2022年第5期32卷 981-998,F0003页

作者： ZHANG Jingjing ZHU Wenbo ZHU lianqi li yanhong College of Geography and Environmental Science Henan UniversityKaifengHenan475004China

The trade-offs and synergies of forest ecosystem service are important research topics for several *** multi-scale analysis of service trade-offs and synergies assists in the implementation of more effective forest resource *** on multi-source data including forest distribution,topography,NDVI,meteorology and soil conditions,key forest ecosystem services,including total forest volume,carbon storage,water yield,soil retention and habitat quality were mapped and evaluated for the Funiu Mountain Region through integrated deployment of the CASA model,the InVEST3.2 model and the ArcGIS10.2 *** characteristics of trade-offs and synergies among different ecosystem services were then mapped and considered across multiple spatial scales(i.e.,by region,north and south slopes,vertical belt)using the spatial overlay analysis *** main results are as follows:(1)Mean forest volume is 49.26 m^(3)/ha,carbon density is 156.94 t/ha,water yield depth is 494.46 mm,the unit amount of soil retention is 955.4 t/ha,and the habitat quality index is 0.79.(2)The area of forests with good synergy is 28.79%,and the area of forests with poor synergy is 10.15%,while about 61.06%of forests show severe trade-offs and weak *** overall benefits of forest ecosystem services in the study area are still *** the future,bad synergy and severe trade-off areas should be the focus of forest resource management and efficiency regulation.(3)Synergy between ecosystem services is better for forest on south slope than that on north *** broad-leaved forest belt at moderate elevations on south slope in the mountains(SIII)has the highest synergies,while that at low elevations on north slope(NI)exhibits the lowest synergy levels.

关键词： forest ecosystem services trade-off/synergy multi-scale analysis CASA InVEST Funiu Mountain Region

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TIM-3: a crucial regulator of NK cells in pregnancy

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Cellular & Molecular Immunology 2017年第11期14卷 948-950页

作者： yanhong li Dajin li Meirong Du Laboratory for Reproductive Immunology Hospital of Obstetrics and GynecologyFudan University Shanghai Medical CollegeShanghaiChina Key Laboratory of Reproduction Regulation of NPFPC SIPPRIRDFudan UniversityShanghaiChina Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases ShanghaiChina

In pregnancy,the maternal immune system(including innate and adaptive immunity)makes elaborate adjustments to endure the embryo’s expression of paternal antigens and to protect the embryo from attacks by invading pathogens such as bacteria or viruses.1 As the predominant innate immune cells during gestation,natural killer(NK)cells have been proven to mediate the establishment of maternal-fetal immune tolerance and to initiate appropriate defenses against infections.2 Tim-3,a member of the T-cell immunoglobulin and mucin domain proteins,has emerged as a key molecule in both innate and adaptive responses and represents a promising novel therapeutic target.

关键词： pregnancy immunity predominant

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Synthesis and electrochemical performance of liMnPO_4 /C composites cathode materials

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Rare Metals 2012年第5期31卷 474-478页

作者： ZHONG Shengkui XU Yuebin li yanhong ZENG Honghu li Wei WANG Jian College of Environmental Science and Engineering Guilin University of Technology Guilin 541004 China Guangxi Key Laboratory of Environmental Engineering Protection and Assessment Guilin University of Technology Guilin 541004 China

liMnPO_4 /C composites were synthesized via solid-state reaction with different carbon sources: sucrose, citric acid and oxalic acid. The sam- ples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical performance test. The results of XRD reveal that carbon coating has no effect on the phase of liMnPO_4 . The liMnPO_4 /C synthesized at 600 °C with citric acid as carbon source shows an initial discharge capacity of 117.8 mA·hg^-1 at 0.05 C rate. After 30 cycles, the capacity remains 98.2 mAh·g^-1 . The improved electrochemical properties of liMnPO_4 /C is attributed to the decomposition of organic acid during the sintering process.

关键词： lithium-ion battery cathode material carbon coating liMnPO^4

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Advance in 3D self-supported amorphous nanomaterials for energy storage and conversion

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Nano Research 2023年第7期16卷 10597-10616页

作者： Baohong Zhang yanhong li Haoze Bai Binbin Jia Di liu lidong li School of Chemistry Beihang UniversityBeijing 100191China Department of Chemistry Tsinghua UniversityBeijing 100084China

The advancement of next-generation energy technologies calls for rationally designed and fabricated electrode materials that have desirable structures and satisfactory ***-dimensional(3D)self-supported amorphous nanomaterials have attracted great enthusiasm as the cornerstone for building high-performance *** particular,tremendous efforts have been devoted to the design,fabrication,and evaluation of self-supported amorphous nanomaterials as electrodes for energy storage and conversion devices in the past ***,the electrochemical performance of devices assembled with 3D self-supported amorphous nanomaterials still remains to be dramatically promoted to satisfy the demands for more practical *** this review,we aim to outline the achievements made in recent years in the development of 3D self-supported amorphous nanomaterials for a broad range of energy storage and conversion *** firstly summarize different synthetic strategies employed to synthesize 3D nanomaterials and to tailor their composition,morphology,and ***,the performance of these 3D self-supported amorphous nanomaterials in their corresponding energy-related reactions is ***,we draw out our comprehensive understanding towards both challenges and prospects of this promising field,where valuable guidance and inspiration will surely facilitate further development of 3D self-supported amorphous nanomaterials,thus enabling more highly efficient energy storage and conversion devices that play a key role in embracing a sustainable energy future.

关键词： three-dimensional(3D)self-supported amorphous nanomaterials synthetic strategy energy storage energy conversion

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Effect of Yb^(3+) concentration on the structures and upconversion luminescence properties of Y_2O_3:Er^(3+) ultrafine phosphors

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Rare Metals 2008年第6期27卷 603-607页

作者： ZHANG Yongming li yanhong ZHANG Yang HONG Guangyan YU Yingning School of Materiasls Science and Engineering Shenyang Institute of Chemical Technology Shenyang 110142 China Key Laboratory of Rare Earth Chemistry and Physics Chinese Academy of Sciences Changchun 130022 China

Y2O3：Er^3＋ ultrafine phosphors with a varying Yb^3＋ ion concentration were prepared by a urea homogeneous precipitation method. The results of XRD show that all the samples are of a pure cubic structure and the average crystallite sizes can be calculated as 45, 34, and 28 nm for Y2O3：Er^3＋ ultrafine phosphors with Yb^3＋ ion concentrations of 0, 10%, and 20%, respectively. The lattice constant and cell volume of the ultrafine phosphors decrease with enhancing Yb^3＋ ion concentration. The upconversion luminescence spectra of all the samples were studied under 980 nm laser excitation. The strong green and red upconversion emission were observed, and attributed to the ^2H11/2→^4I15/2, ^4S3/2 → ^4I15/2 and ^4F9/2 →^4I15/2 transitions of Er^3＋, respectively. The intensity of red emission increases with increasing Yb^3＋ ion concentration. The effect of Yb^3＋ ion concentration on the structures and upconversion luminescence mechanism were discussed.

关键词： ultrafine phosphor ion concentration urea homogeneous precipitation method upconversion luminescence

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