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j.urnal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu S.j.Liu B.w.ng w.B.sun X.j.Liu Z.w.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China key laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China w.ihai Institute for Bionics-j.lin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys w.th different phase compositions w.re prepared by various Y additions(x=0.4,3,and 6 w..%)to adj.st the compressive properties and energy absorption *** characterization methods w.re then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests w.re performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results show.d that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),w.phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).w.en the Y content ranges betw.en 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj.m^(3)to 10.97 Mj.m^(3)at RT,w.ich is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

The Grow.h of Semi-insulating InP（Fe） byVapor-phase Epitaxy Using N2+H2 as a Carrier Gas

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Chinese j.urnal of Lasers 1996年第1期B5卷 72-76页

作者： sun Hongbo LI Yudong CHEN Songyan HU Lizhong SU Shichang LIU Shiyong(state key laboratory on integrated optoelectronics,j.lin University Region, Changchun 130023, China) j.lin Univ Changchun China

The grow.h of semi-insulating SI: InP （Fe） using N2+H2as a carrier gas through chloride vapor phase（VPE） is reported for the first time. The incorporation of Fe is achieved by using FeCl2generated by reaction of HCl and Fe. The transport of Fe as FeCl2,commonly reduced by a large hydrogen partial pressure in convertional VPE system, has greatly improved by the use of N2. A proper N2to H2ratio for the iror. incorporation and optimal grow.h procedure are discussed. The resitivity of 5×10～8Ω·cm is comparable w.th the best results by MOCVD. Especially the technique has been successfully used for the preparation of quantum w.ll laser diode.

关键词： VPE MQE SI-InP(Fe). far-field paterns

Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by w.sterlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU He sun state key laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

The diverse climates,distribution of snow.and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the w.sterlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in w.sterlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow.UYE),Lancang(ULC),Nuj.ang(UNj.,and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results show.d that:(1)The annual runoff in the maj.rity of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI show.d a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing betw.en the 1980s and 2000s,w.th the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the w.sterlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to w.rm season temperature changes in the most w.sterlies-dominated upper basins has decreased,w.ile the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change w.sterlies and monsoon Runoff variations Large-scale circulation factors

Coupled Cu doping and Z-scheme heteroj.nction for synergistically enhanced tetracycline photodegradation

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Nano Research 2024年第7期17卷 5937-5948页

作者： Huidong Shen Chunming Yang Song Hong Leiduan Hao Liang Xu Alex w.Robertson Zhenyu sun Country state key laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shaanxi key laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China Department of Physics University of WarwickCoventry CV 47ALUK

Semiconductor-based photocatalysis by utilizing solar energy for sustainable organic pollutant elimination has been a promising tactic to alleviate environmental ***,the development of robust and efficient photocatalysts to degrade organic pollutants still faces maj.r challenges because of insufficient charge *** w. design and fabricate a heteroj.nction consisting of copper,carbon-modified TiO_(2),and sulfur-doped g-C_(3)N_(4)nanosheets(i.e.,S-C_(3)N_(4)/Cu/C-TiO_(2)).The heterostructure affords a remarkable synergistic photocatalysis for tetracycline hydrochloride degradation,achieving an 82.6%removal efficiency w.thin 30 min under visible light irradiation,about 15.4 and 7.3 times higher than that of S-C_(3)N_(4)and C-TiO_(2),*** superior performance is attributed to the synergy betw.en Cu doping and the Z-scheme heteroj.nction,w.ich not only enhances the interfacial electric field effect,facilitating charge separation,but also boosts the redox *** charge carrier transfer betw.en Cu/C-TiO_(2)and S-C_(3)N_(4)follow. a Z-scheme,as verified by trapping experiments,electron spin-resonance spectroscopy,and density functional theory ***,the tetracycline hydrochloride degradation pathw.ys are enunciated by liquid chromatograph mass spectrometry *** w.rk provides an effective approach for constructing high-performance photocatalysts that have potential in environmental remediation.

关键词： photocatalysis Cu doping Z-scheme heteroj.nction electrons and holes separation tetracycline degradation

InGaAs/InGaAlAs Strain-compensated Multiple-quantum-w.ll Lasers w.th Improved Temperature Characteristic

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Chinese j.urnal of Lasers 1999年第5期8卷 3-5页

作者： sun Ke w.NG j.anhu ZHOU Dan PENG j.hu(state key Lab. on integrated optoelectronics, Electronic Engineering Dept,Tsinghua University, Beij.ng 100084, China) 清华大学集成光电子学联合国家重点实验室北京 100084

It is reported on realization of pulsed operation of InGaAs/InGaAlAs straincompensated multiple-quantum-w.ll lasers at room temperatures. The w.rking w.velength is 1. 56μm; the threshold current density for the stripe w.veguide lasers is less than 1. 85kA/cm2； for the ridge w.veguide lasers, the threshold current is 35 mA. The incorporation of compensated strain, w.ich makes the multiple-quantum-w.ll design applicable, leads to an obvious improvement on device temperature characteristic.

关键词： strain-compensation quantum w.ll laser diode InGaAlAs/InP

New.perspectives on deep carbon cycling

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Science China Earth Sciences 2024年第8期67卷 2411-2422页

作者： w.idong sun Center of Deep Sea Research Key Laboratory of Ocean Observation and ForecastingInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan laboratory Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

The proto-atmosphere serves as a crucial starting point for the carbon *** based on atmospheric data from Mars and Venus suggest that Earth's proto-atmosphere contained>110 bar of CO_(2)and>2.6 bar of *** protoatmosphere had over 1000 bar of w.ter vapor during the magma ocean stage,assuming the proto-ocean had a volume of tw. oceans of *** this stage both w.ter and carbon dioxide w.re in a supercritical state at the magma-atmosphere *** serpentinization reactions occurred due to rock-w.ter interaction,producing abundant ***,nitrogen is reduced to ammonia,and carbon dioxide to methane,forming carbonate *** proto-atmosphere dominated by methane,ammonia,and hydrogen formed a significant amount of amino acids through *** process is essential not only to the origin of life,but also to the early carbon-nitrogen cycle on *** the Hadean eon,a large amount of CO_(2)w.s sequestered as carbonate and organic ***,it mainly entered the deep mantle through mantle overturn or *** the mantle transition zone,carbonate undergoes“Redox freezing”,w.ere carbonate is reduced to diamond through oxidation of ferrous iron in the *** the low.r mantle,Fe^(2+)undergoes disproportionation reactions,forming Fe^(3+)and metallic *** these,Fe^(3+)mainly resides in bridgmanite,thereby increasing the oxygen fugacity of the low.r mantle,w.ile metallic iron falls to the Earth's *** distribution of carbon in the mantle is crucial for deep carbon *** density curves of diamond and mantle peridotite melt intersect at the bottom of the mantle transition zone(about 660 km).This density crossover leads to the accumulation of diamond during the magma ocean *** materials such as subducting slabs enter the low.r mantle,compensatory upw.lling of low.r mantle material *** enters the upper mantle,decomposes,releasing Fe^(3+)ions and oxidizes diamond

关键词： Carbon cycling Proto-atmosphere Amino acids Subduction initiation Passive margin subduction Atmospheric carbon dioxide

Dominant w.ody plant species recognition w.th a hierarchical model based on multimodal geospatial data for subtropical forests

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j.urnal of Forestry Research 2024年第3期35卷 111-130页

作者： Xin Chen Yuj.n sun state Forestry&Grassland Administration key laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been w.dely used,leading to a w.alth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant w.ody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data w.th the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data w.re computed.A hierarchical model obtained information on forest distribution and area and the dominant w.ody plant *** results suggest that combining data sources from the S1 w.nter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant w.ody species recognition,using S1 w.nter and S2 data across all four seasons w.s *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE w.re 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely w.ll for extracting information about dominant w.ody plant *** the results using the GEE application allow. for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant w.ody plant species Subtropics Model performance

Multi-Sensor Fusion Adaptive Estimation for Nonlinear Under-observed System w.th Multiplicative Noise

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Chinese j.urnal of Electronics 2024年第1期33卷 282-292页

作者： Yongpeng CUI Xiaoj.n sun School of Electronic Engineering Heilongjiang University key laboratory of Information Fusion Estimation and Detection

The adaptive fusion estimation problem w.s studied for the multi-sensor nonlinear under-observed systems w.th multiplicative noise. A one-step predictor w.th state update equations w.s designed for the virtual state w.th virtual noise first of all. An extended incremental Kalman filter(EIKF) w.s then proposed for the nonlinear under-observed systems. Furthermore, an adaptive filtering method w.s given for optimization. The fusion adaptive incremental Kalman filter w.ighted by scalar w.s finally proposed. The comparison analysis w.s made to verify the optimization of the state estimation using adaptive filtering method in the filtering process.

关键词： Adaptive systems Information filters Matrices Adaptive estimation Kalman filters state estimation Nonlinear systems

Organic thin-film transistors and related devices in life and health monitoring

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Nano Research 2024年第2期17卷 426-444页

作者： Chenfang sun Tie w.ng Tianj.n key laboratory of Drug Targeting and Bioimaging Life and Health Intelligent Research InstituteTianjin University of TechnologyTianjin 300384China

The early determination of disease-related biomarkers can significantly improve the survival rate of ***,a series of explorations for new.diagnosis technologies,such as optical and electrochemical methods,have been devoted to life and health *** thin-film transistor(OTFT),as a state-of-the-art nano-sensing technology,has attracted significant attention from construction to application ow.ng to the merits of being label-free,low.cost,facial,and rapid detection w.th multi-parameter ***,interference from non-specific adsorption is inevitable in complex biological samples such as body liquid and exhaled gas,so the reliability and accuracy of the biosensor need to be further improved w.ile ensuring sensitivity,selectivity,and ***,w. overview.d the composition,mechanism,and construction strategies of OTFTs for the practical determination of disease-related biomarkers in both body fluids and exhaled *** results show.that the realization of bio-inspired applications w.ll come true w.th the rapid development of high-effective OTFTs and related devices.

关键词： organic thin-film transistors biosensors biomarkers organic bioelectronics organic semiconductors healthcare