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Eco-environment contribution of agroforestry to agriculture development in the plain area of China—Huai'an Prefecture, Jiangsu Province as the case study area

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Journal of Environmental Sciences 2005年第2期17卷 327-331页

作者： renhong-chang LUYong-long LIUCan MENGQing-hua SHIYa-juan ResearchCenterforEco-EnvironmentalSciences ChineseAcademyofSciencesBeijing100085China／／AcademyofForestInventoryandPlanningStateForestryAdministrationBeijing100714China ResearchCenterforEco-EnvironmentalSciences ChineseAcademyofSciencesBeijing100085China ChinaNationalForestryEconomicsandDevelopmentResearchCenter Beijing100714China AcademyofForestInventoryandPlanning StateForestryAdministrationBeijing100714China

For improving the environmental quality and ensuring supply of wood and non-timber forest products, many forests have been planted in plain areas of China. Scientists have studied their benefits, almost all of the approaches were based on fixed-point data, and few was considered on the non-efficient factors and temporal scale effects. This paper studies the positive and negative benefits at a large temporal scale, and the effects of plain afforestation on stockbreeding and rural economy. The benefits of plain afforestation, correlation coefficiency of agroforestry and production factors are analyzed via stochastic frontier modeling in Huanghuaihai Plain Area of China; elastic coefficient of agroforestry, husbandry, farming, and total output of agricultural sector are calculated through adopting partial differential equation. Some conclusions can be drawn that, plain forests have an important effect on the development of plain agriculture. But shelterbelts and small-scale forests have different effect on the development of agricultural economy. Shelterbelts have negative effect on the industries, but small-scale forest has positive effect. On the whole, contribution of forest resource to value of animal husbandry and gross production value of agriculture is positive, and to the value of farming is negative.

关键词： plain afforestation agricultural development agroforestry plain area of China

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Efficacy and safety of Y- 2 sublingual tablet for patients with acute ischaemic stroke: protocol of a phase III randomised double- blind placebo- controlled multicentre trial

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Stroke & Vascular Neurology 2024年第1期9卷 90-95页

作者： Yu Fu renhong Tang Rong Chen Anxin Wang Jinsheng Ren Shunwei Zhu Xiaofei Feng Dongsheng Fan Deparment of Neurology Peking University Third HospitalBeijingChina State Key Laboratory of Neurology and Oncology Drug Development NanjingJiangsuChina Simcere Pharmaceutical Group Limited NanjingJiangsuChina Neurodawn Pharmaceutical Co. LtdNanjingJiangsuChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina

Background and purpose Clinical studies have demonstrated that edaravone dexborneol can improve the functional outcomes in patients with acute ischaemic stroke(AIS).The present clinical trial aimed at testing the efficacy and safety of Y-2 sublingual tablet on 90-day functional outcome in patients with *** and design This is a randomised,double-blind,placebo-controlled,multicentre,parallel-group trial of Y-2 sublingual tablet on patients with *** estimated 914 patients at age of 18–80 years with AIS within 48 hours after symptom onset from 40 hospitals will be randomly assigned to receive Y-2 sublingual tablet or placebo for 14 *** are at score 6–20 points on National Institutes of Health Stroke Scale(NIHSS)and had a modified Rankin Scale(mRS)≤1 before this stroke,except mechanical thrombectomy and neuroprotective agents *** outcomes The primary outcome is the proportion of patients with mRS≤1 on day 90 after *** efficacy outcomes include mRS score on day 90,the proportion of patients with mRS≤2 on day 90;the change of NIHSS score from baseline to day 14 and the proportion of patients with NIHSS score≤1 at the days 14,30 and *** This trial will provide valuable evidence for the efficacy and safety of Y-2 sublingual table for improving 90 days the functional outcomes in patients with *** registration number NCT04950920.

关键词： patients protective centre

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Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8Mo stainless steel

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Journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang Liu chang-jun Wang chang Liu School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8Mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and M23C precipitates form,which are the major strengthening phases of PH13-8Mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8Mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 MPa,1432 MPa and 63 J,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and M23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment Microstructure Mechanical property

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Inverse-time Backup Protection Based on Unified Characteristic Equation for Distribution Networks with High Proportion of Distributed Generations

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 202-212页

作者： Nana chang Guobing Song Zhongxue chang Yuping Zheng Xingang Yang the School of Electrical Engineering Xi’an Jiaotong UniversityXi’anChina State Key Laboratory of Smart Grid Protection and Control NARI Group CorporationNanjingChina Electric Power Research Institute of State Grid Shanghai Electric Power Company ShanghaiChina

The setting work of backup protection using steady-state current is tedious,and mismatches occasionally occur due to the increased proportion of distributed generations(DGs)connected to the power ***,there is a practical need to study a backup protection technology that does not require step-by-step setting and can be adaptively *** paper proposes an action sequence adaptive to fault positions that uses only positive sequence fault component(PSFC)*** the influence of DGs,the unified time dial setting can be obtained by selecting specific *** protection performance is improved by using the adjacent upstream and downstream protections to meet the coordination time interval in the case of metallic faults at the near-and far-ends of the ***,the expression and implementation scheme for inverse-time backup protection(ITBP)based on the unified characteristic equation is *** results show that this scheme can adapt to DG penetration scenarios and can realize the adaptive coordination of multi-level relays.

关键词： Inverse-time backup protection(ITBP) distributed generation(DG) positive sequence fault component(PSFC)voltage unified characteristic equation adaptive coordination

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Polymeric piezoelectric accelerometers with high sensitivity,broad bandwidth,and low noise density for organic electronics and wearable microsystems

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Microsystems & Nanoengineering 2024年第3期10卷 63-74页

作者： chang Ge Edmond Cretu The Department of Electrical and Computer Engineering The University of British ColumbiaVancouverBCCanada

Piezoelectric accelerometers excel in vibration *** the emerging trend of fully organic electronic microsystems,polymeric piezoelectric accelerometers can be used as vital front-end components to capture dynamic signals,such as vocal vibrations in wearable speaking assistants for those with speaking ***,high-performance polymeric piezoelectric accelerometers suitable for such applications are *** organic compounds such as PVDF have inferior properties to their inorganic counterparts such as ***,most existing polymeric piezoelectric accelerometers have very unbalanced performance *** often sacrifice resonance frequency and bandwidth for a flat-band sensitivity comparable to those of PZT-based accelerometers,leading to increased noise density and limited application *** this study,a new polymeric piezoelectric accelerometer design to overcome the material limitations of PVDF is *** new design aims to simultaneously achieve high sensitivity,broad bandwidth,and low *** samples were manufactured and characterized,demonstrating an average sensitivity of 29.45 pC/g within a±10 g input range,a 5%flat band of 160 Hz,and an in-band noise density of 1.4μg/√*** results surpass those of many PZT-based piezoelectric accelerometers,showing the feasibility of achieving comprehensively high performance in polymeric piezoelectric accelerometers to increase their potential in novel applications such as organic microsystems.

关键词： piezoelectric polymeric overcome

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Recent Progresses of the DAMPE Mission

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空间科学学报 2024年第4期44卷 633-642页

作者： chang Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033 School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026

The DArk Matter Particle Explorer(DAMPE)is a space high-energy particle andγ-ray detector whose major scientific goals are the indirect detection of dark matter particles,the origin of cosmic rays and highenergyγ-ray *** its successful launch in December 2015,the DAMPE has been operated smoothly in orbit for more than 8 *** direct measurements of the boron-to-carbon and boron-to-oxygen flux ratios,and the proton+Helium spectrum up to 316 TeV have been obtained,revealing new spectral features with very high *** search results ofγ-ray spectral line and fractionally charged particles indicate a good potential of DAMPE for indirect dark matter detection and new physical discovery in *** DAMPE measurements are expected to significantly advance our understanding of the fundamental problems in astroparticle physics.

关键词： DAMPE Dark matter Indirect detection Cosmic rays

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Preface to the Special Issue:Additive Manufacturing—Expanding Production Horizon

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 1-2页

作者： Lai-chang Zhang Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing(AM),commonly known as 3D printing,has become a transformative technology that has a profound impact on various industrial *** encompasses a set of techniques for building objects layer by layer from digital *** conventional subtractive manufacturing methods that involve removing material from large blocks,AM adds material incrementally,providing unprecedented design flexibility and efficiency.

关键词： removing printing Expanding

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Soliton microcomb generation by cavity polygon modes

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Opto-Electronic Advances 2024年第8期7卷 6-14页

作者： Botao Fu renhong Gao Ni Yao Haisu Zhang Chuntao Li Jintian Lin Min Wang Lingling Qiao Ya Cheng State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-Intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China Research Center for Frontier Fundamental Studies Zhejiang LabHangzhou 311100China Engineering Research Center for Nanophotonics&Advanced Instrument Ministry of EducationSchool of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China School of Physical Science and Technology ShanghaiTech UniversityShanghai 200031China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Shanghai Research Center for Quantum Sciences Shanghai 201315China Hefei National Laboratory Hefei 230088China

Soliton microcombs,which require the hosting cavity to operate in an anomalous dispersion regime,are essential to integrate photonic *** the past,soliton microcombs were generated on cavity whispering gallery modes(WGMs),and the anomalous dispersion requirement of the cavity made by normal dispersion material was achieved through structural dispersion *** inevitably degrades the cavity optical quality factor(Q)and increases pump threshold power for soliton comb *** overcome the challenges,here,we report a soliton microcomb excited by cavity polygon *** modes display anomalous dispersion at near-infrared while optical Q factors exceeding 4×10^(6) are ***,a soliton comb spanning from 1450 nm to 1620 nm with a record low pump power of 11 m W is demonstrated,a three-fold improvement compared to the state of the art on the same material platform.

关键词： thin-film lithium niobate nonlinear optics microresonators

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Breakthrough in Li-mediated continuous electrosynthesis of ammonia

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Science China Chemistry 2024年第10期67卷 3191-3192页

作者： Fei Zhan chang Yu State Key Laboratory of Chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Ammonia(NH3)ranks among the manufactured chemicals,with an annual production surpassing 182 million tons[1],which is an indispensable raw material for fertilizer industry and has been recognized as a promising carbon-... 详细信息

关键词： ammonia Ammonia suppl

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An interview with *** Zhang

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High Power Laser Science and Engineering 2024年第3期12卷 122-125页

作者： Guoqing chang Institute of Physics Chinese Academy of SciencesBeijingChina

*** Zhang,a distinguished physicist,has made significant contributions in the fields of high-energy-density physics and inertial confinement *** of these,he was elected academician of the Chinese Academy of Sciences in 2003,academician of the German National Academy of Sciences in 2007,Fellow of the Academy of Sciences for the Developing World(TWAS)in 2008,foreign member of the Royal Academy of Engineering in the United Kingdom in 2011 and foreign associate of the National Academy of Sciences in the United States in *** 2015,he was awarded the prestigious Edward Teller Medal,the most important international award in inertial confinement fusion and high-energy-density *** 2021,he was awarded the Future Science Prize in Physical Sciences.

关键词： interview award Jie

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