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海南岛土壤粘粒矿物特征与土壤系统分类

土壤学报 2002年第4期39卷 467-475页

作者：杨德涌陈世俭马毅杰中国科学院南京土壤研究所南京210008

研究了海南岛不同母质土壤的粘粒矿物特征:都含有较多的高岭石,其中玄武岩发育土壤粘粒中高岭石最多,但其结晶最差。片岩和紫色砂岩发育土壤含相当多的水云母,粘粒部分水云母含量高达40％～45％,石灰岩发育土壤水云母含量亦较高,达20％... 详细信息

研究了海南岛不同母质土壤的粘粒矿物特征:都含有较多的高岭石,其中玄武岩发育土壤粘粒中高岭石最多,但其结晶最差。片岩和紫色砂岩发育土壤含相当多的水云母,粘粒部分水云母含量高达40％～45％,石灰岩发育土壤水云母含量亦较高,达20％～37％,此类水云母属二八面体型的水化白云母。玄武岩和花岗岩发育的“湿润”土壤粘粒中针铁矿与赤铁矿的含量之比为（3～4）:1,而花岗岩发育的“常湿”土壤粘粒中只有针铁矿,不见赤铁矿存在,证明土壤中氧化铁矿物的类型是土壤湿润状况的反应,在中国土壤系统分类中可以用来区分“湿润”和“常湿”土壤的一个指标。

关键词：海南岛土壤粘粒矿物特征土壤系统分类

Experimental investigation on shear strength deterioration at the interface between different rock types under cyclic loading

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3063-3079页

作者： Qiong Wu Zhiqi Liu Huiming Tang Liangqing wang Xiaoxue Huo Zhen Cui shiyu Li Bo Zhang Zhiwei lin Faculty of Engineering China University of GeosciencesWuhan430074China Guangxi Fangchenggang Beitou Environmental Protection Water Co. Ltd.Fangchenggang538021China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The shear strength deterioration of bedding planes between different rock types induced by cyclic loading is vital to reasonably evaluate the stability of soft and hard interbedded bedding rock slopes under earthquake;however,rare work has been devoted to this subject due to lack of *** this study,experimental investigations on shear strength weakening of discontinuities with different joint wall material(DDJM)under cyclic loading were conducted by taking the interface between siltstone and mudstone in the Shaba slope of Yunnan Province,China as research objects.A total of 99 pairs of similar material samples of DDJM(81 pairs)and discontinuities with identical joint wall material(DIJM)(18 pairs)were fabricated by inserting plates,engraved with typical surface morphology obtained by performing three-dimensional laser scanning on natural DDJMs sampled from field,into mold *** shear tests were conducted on these samples to study their shear strength changes with the cyclic number considering the effects of normal stress,joint surface morphology,shear displacement amplitude and shear *** results indicate that the shear stress *** displacement curves under each shear cycle and the peak shear strength *** number curves of the studied DDJMs are between those of DIJMs with siltstone and mudstone,while closer to those of DIJMs with *** peak shear strengths of DDJMs exhibit an initial rapid decline followed by a gradual decrease with the cyclic number and the decrease rate varies from 6%to 55.9%for samples with varied surface morphology under different testing *** normal stress,joint surface morphology,shear displacement amplitude and shear rate collectively influence the shear strength deterioration of DDJM under cyclic shear loading,with the degree of influence being greater for larger normal stress,rougher surface morphology,larger shear displacement amplitude and faster shear rate.

关键词： Discontinuities with different joint wall material(DDJM) Discontinuities with identical joint wall material(DIJM) Cyclic shear test Shear strength deterioration Joint surface morphology Shear displacement amplitude Shear rate Normal stress

Preparation of Fe-As alloys by mechanical alloying and vacuum hot-pressed sintering:microstructure evolution,mechanical properties,and mechanisms

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Rare Metals 2024年第8期43卷 3876-3892页

作者： Fei Chai Fei-Ping Zhao Zhan Hu shi-Yi Wen Ben-Hammouda Samia Ze-lin Fu Xin-Ting Lai Yan-Jie Liang Xiao-Bo Min Li-Yuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Institute of Environmental EngineeringCentral South UniversityChangsha 410083HunanChin State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Building Civiland Environmental EngineeringConcordia UniversityMontreal H3G 1M8Canada

Arsenic materials have attracted great attention due to their unique ***,research concerning iron-arsenic(Fe-As) alloys is very scarce due to the volatility of As at low temperature and the high melting point of ***,a new Fe-As alloy was obtained by mechanical alloying(MA) followed by vacuum hot-pressed sintering(VHPS).Moreover,a systematic study was carried out on the microstructural evolution,phase composition,leaching toxicity of As,and physical and mechanical properties of Fe-As alloys with varying weight fractions of As(20%,25%,30%,35%,45%,55%,65%,and 75%).The results showed that pre-alloyed metallic powders(PAMPs) have a fine grain size and specific supersaturated solid solution after MA,which could effectively improve the mechanical properties of Fe-As alloys by VHPS.A high density(> 7.350 g·cm^(-3)),low toxicity,and excellent mechanical properties could be obtained for FeAs alloys sintered via VHPS by adding an appropriate amount of As,which is more valuable than commercial Fe-As *** Fe-25% As alloy with low toxicity and a relatively high density(7.635 g·cm^(-3)) provides an ultra-high compressive strength(1989.19 MPa),while the Fe-65% As alloy owns the maximum Vickers hardness(HVo.5 899.41).After leaching by the toxicity characteristic leaching procedure(TCLP),these alloys could still maintain good mechanical performance,and the strengthening mechanisms of Fe-As alloys before and after leaching were *** in the grain size,micro structure,and phase distribution induced significant differences in the compressive strength and hardness.

关键词： Mechanical alloying Vacuum hot-pressed sintering High-pressure Arsenic-iron alloys Mechanical properties

Dimethylsulfoniopropionate (DMSP) Increases Longevity and Mitochondrial Function in Caenorhabditis elegans: Implications for the Role of the Global Sulfur Cycle in Terrestrial Ecosystems

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Environment & Health 2024年第8期2卷 572-585页

作者： Hongyuan Li Peng Ji Yue Cao Zhitao Cui Jingwei Gao Hongshuang wang Cong lin Yibo wang Xiaohui wang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The Key Laboratory of Molecular Epigenetics of the Ministry of Education Northeast Normal UniversityChangchun 130024China Department of Geriatrics The First Hospital of Jilin UniversityChangchun 130021China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Beijing National Laboratory for Molecular sciences Beijing 100190China

Dimethylsulfoniopropionate(DMSP)is a compound synthesized by marine phytoplankton that contributes to the oceanic sulfur ***,DMSP has also been found in algal species and several terrestrial plants,forming part of the global sulfur ***,compared to its role in the marine environment,the impact of DMSP on terrestrial ecosystems remains relatively *** this study,DMSP was shown to promote longevity and prevent age-associated functional decline in Caenorhabditis elegans(***),a soil-dwelling *** decreased mitochondrial content and improved mitochondrial function in *** at the old stage,which was via enhancing autophagy *** was demonstrated that DMSP significantly increased the expression of autophagy and mitophagy genes during ***,DMSP protected against Parkinson’s disease(PD)induced byα-synuclein(α-syn)aggregation via *** studies showed that DMSP directly activated nuclear translocation of the Skinhead-1(SKN-1)transcription factor from the ***,SKN-1 was involved in DMSP-induced autophagy and played a key role in lifespan extension andα-syn clearance in *** conclusion,DMSP delays physiological aspects of aging in ***,providing insights into the interplay between the global sulfur cycle and terrestrial organisms.

关键词： DMSP C.elegans terrestrial ecosystem aging autophagy

Preliminary assessment of the data appropriateness of electronic health records for real-world studies:A survey of hospitals in a developing region in China

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chinese Medical Journal 2024年第9期137卷 1130-1131页

作者： Yuelin Yu lin Zhuo Ruogu Meng Wanqian Guo Yuanyuan Chen Yunjing Zhang Ying Chen Hongjing shi Zhi lin Siyan Zhan Shengfeng wang Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Research Center of Clinical Epidemiology Peking University Third HospitalBeijing 100191China National institute of Health Data science Peking UniversityBeijing 100191China Health science Center Peking UniversityBeijing 100191China

To the Editor:Assessment of data appropriateness is a process to answer whether electronic health records(EHRs)from routine healthcare practices couldt intended study purposes,for example,available to be proceeded,with enough individual records,with relevant information able to be extracted from records,etc.[1-3]This has been increasingly underscored as a prerequisite when using EHRs(one important type of real-world data[RWD])for scientic purposes.[4-6]Although controversies remain on the denitions,types and assessment methods of the dimensions of RWD appropriateness,the latest ofcial guidelines(i.e.,from the *** and Drug Administration[FDA][4]and China National Medical Products Administration[NMPA][6])suggest that the assessment start from a preliminary stage on variable existence,and subsequently deepen into the issue of data value(such as missing value,outliers,etc.),as the preliminary assessment is the foundation of the overall RWD appropriateness.[7]Little is known about the appropriateness of EHRs in developing regions,which feature high visit volumes and a great number of ***,this study aimed to preliminarily investigate RWD appropriateness from hospitals in developing regions from the perspective of core variables’comparison.

关键词： electronic dimensions records

Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet

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Atmospheric and Oceanic science Letters 2024年第5期17卷 47-53页

作者： Yumeng Liu Xianhong Meng lin Zhao S-Y.Simon wang Lixia Zhang Zhaoguo Li Chan wang Yingying An Key Laboratory of Cryospheric science and Frozen soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina Zoige Plateau Wetlands Ecosystem Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina University of chinese academy of sciences BeijingChina Utah Climate Center Utah State UniversityLoganUSA The State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina

Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal *** study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,pshift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer *** empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR *** influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°***,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ.

关键词： Summer precipitation East Asian subtropical westerly jet Three River Source Region Atlantic-Eurasian teleconnection

Regional Simulation of soil Organic Carbon Dynamics for Dry Farmland in East China by Coupling a 1:500000 soil Database with the Century Model

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Pedosphere 2011年第3期21卷 277-287页

作者： wang shi-Hang shi Xue-Zheng ZHAO Yong-Cun D. C. WEINDORF YU Dong-Sheng XU Sheng-Xiang TAN Man-Zhi SUN Wei-Xia State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 (China) Louisiana State University AgCenter Baton Rouge Louisiana 70803 (USA) Graduate University of chinese academy of sciences Beijing 100049 (China)

Changes in soil organic carbon (SOC) in agricultural soils influence soil quality and greenhouse gas concentrations in the atmosphere. Dry farmland covers more than 70% of the whole cropland area in China and plays an important role in mitigating carbon dioxide (CO2) emissions. In this study, 4109 dry farmland soil polygons were extracted using spatial overlay analysis of the soil layer (1:500000) and the land use layer (1:500000) to support Century model simulations of SOC dynamics for dry farmland in Anhui Province, East China from 1980 to 2008. Considering two field-validation sites, the Century model performed relatively well in modeling SOC dynamics for dry farmland in the province. The simulated results showed that the area-weighted mean soil organic carbon density (SOCD) of dry farmland increased from 18.77 Mg C ha1 in 1980 to 23.99 Mg C ha1 in 2008 with an average sequestration rate of 0.18 Mg C ha1 year?1. Approximately 94.9% of the total dry farmland area sequestered carbon while 5.1% had carbon lost. Over the past 29 years, the net SOC gain in dry farmland soils of the province was 19.37 Tg, with an average sequestration rate of 0.67 Tg C year1. Augmentation of SOC was primarily due to increased consumption of nitrogen fertilizer and farmyard manure. Moreover, SOC dynamics were highly differentiated among dry farmland soil groups. The integration of the Century model with a fine-scale soil database approach could be conveniently utilized as a tool for the accurate simulation of SOC dynamics at the regional scale.

关键词： agricultural soils C02 emissions greenhouse gas soil organic carbon density soil quality

Stable carbon isotope composition and intrinsic water use efficiency in plants along an altitudinal gradient on the eastern slope of Yulong Snow Mountain, China

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Ecological Processes 2024年第2期13卷 218-230页

作者： Feng Jiang Tao Pu Zi-Jing Xue Yan-Wei Ma Xiao-Yi shi Fu-Xi shi College of Geography and Environmental sciences Zhejiang Normal University Yulong Snow Mountain Glacier and Environment Observation and Research Station/State Key Laboratory of Cryospheric sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of Forestry Jiangxi Agricultural University

Background Stable carbon isotope composition(δ13Cp) can be used to estimate the changes in intrinsic water use efficiency（iWUE） in plants,which helps us to better understand plants' response strategies to climate *** study focused on the variations in δ13Cpand iWUE for the different life-form plants（i.e.,herbs,shrubs,and trees）along an altitudinal gradient（3300,3600,3900,4100,4300,and 4500 m） on the eastern slope of Yulong Snow Mountain,southeastern margin of the Qinghai-Tibet *** response mechanisms of δ13Cpand iWUE for different life-form plants to altitude were thoroughly analyzed in this mountain *** The δ13Cpvalues of plants on the eastern slopes of Yulong Snow Mountain ranged from-30.4‰to-26.55‰,with a mean of-28.02‰,indicating a dominance of *** δ13Cpand iWUE values varied among different life-form plants in the order of herbs> shrubs> trees,particularly in 3600,3900,and 4300 ***δ13Cpand iWUE values for herbs and shrubs increased with altitude and were mainly controlled by air *** two parameters for trees exhibited a trend of initial decrease followed by an increase with *** 3900 m,the δ13Cpand iWUE values decreased with altitude,influenced by soil ***,above 3900 m,the two parameters increased with altitude,mainly regulated by air *** addition,iWUE was positively correlated with leaf P content but negatively correlated with leaf N:P ratio,especially for herbs and trees,suggesting that P plays a key role in modulating iWUE in this *** The diffe rentiated responses of water availability for different life-form plants to a higher altitudinal gradient are regulated by air temperature,soil moisture,and leaf P content in the Yulong Snow *** results provide valuable insights into understanding the wate r-carbon relationships in high-altitude ecosystems.

关键词： Stable carbon isotope Water use efficiency Altitude Life form Yulong Snow Mountain

Frequency-Self-Adaptive Radio Frequency Power Harvester Enabled by Shape-Reconfigurable Liquid Metal

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Electromagnetic science 2024年第2期2卷 91-103页

作者： Cheng Zhang Yuchao wang Zebin Zhu Hai lin Kun wang Xintong shi Yi Du Chaoyun Song Long Ren Qiang Cheng Key Laboratory of Materials for High-Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Hangzhou institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China College of Physical science and Technology Central China Normal UniversityWuhan 430000China Center of Quantum and Matter science and School of Physics Beihang UniversityBeijing 100191China Department of Engineering King’s College LondonLondon WC2R 2LSUK State Key Laboratory of Radio Frequency Heterogeneous Integration College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518000China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430000China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China

Radio frequency(RF)energy harvester as an efficient tool for capturing and converting the flourishing ambient RF energy provides a promising solution for long-term powering the wireless sensor networks and the Internet of things(IoTs).However,the actual distribution of the environmental RF signals is dynamically frequency-dependent due to the diverse wireless terminals only interacting with specified *** take full advantage of the RF energy carrying this characteristic,an intelligent RF energy harvester is in demand to automatically sense the frequency information of an incident signal and conduct the corresponding RF-to-direct current transformation ***,to the best of my knowledge,a frequency-self-adaptive RF harvester is first presented with the help of the shape-reconfigurable liquid metal,which can precisely identify and efficiently convert an arbitrary signal from the frequency span of 1.8 to 2.6 *** with a microcontroller unit and a tensile system,the dynamic functionality of the entire system is comprehensively demonstrated,showing promising potential to significantly advance various fields,including sustainable IoT applications,green wearable technologies,and self-powered devices.

关键词： Liquid metal Radio frequency power harvesting Frequency-self-adaptive Broadband rectification