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Quantitative relationships between vegetation and several pollen taxa in surface soil from North China

Chinese Science Bulletin 2000年第16期45卷 1519-1523页

作者： LI yiyin, ZHANG Xinshi & zhou Guangsheng1. Department of Urbon and Environmental Sciences, Peking University, Beijing 100871, China 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 3. School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024, China Correspondence should be addressed to Li yiyin Department of Urbon and Environmental Sciences Peking University Beijing China School of Urban and Environmental Sciences Northeast Normal University Changchun China Laboratory of Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing China

According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-intercept

关键词： pollen taxa in surface soil vegetation regression parameters (slope term and y-intercept term) representation Northeast China Transect (NECT).

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茄子钵苗全自动移栽机构优化设计与试验

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农业机械学报 2018年第5期49卷 152-160页

作者：赵匀刘星薛向磊张卫星单伊尹周脉乐东北农业大学工程学院哈尔滨150030

为了实现茄子钵苗的全自动机械化移栽,设计了一种全自动茄子钵苗移栽机构,提出了一种以牛顿插值法构建的新型非圆齿轮,建立了茄子钵苗移栽机构运动学模型。通过农艺与农机的结合,以钵盘规格、基质体积比、土钵含水率为试验因素,取苗力... 详细信息

为了实现茄子钵苗的全自动机械化移栽,设计了一种全自动茄子钵苗移栽机构,提出了一种以牛顿插值法构建的新型非圆齿轮,建立了茄子钵苗移栽机构运动学模型。通过农艺与农机的结合,以钵盘规格、基质体积比、土钵含水率为试验因素,取苗力与土钵基质损失率为试验指标,进行了三因素三水平的正交试验,试验结果表明,钵盘规格105穴、基质体积比1、土钵含水率70%~80%时,取苗力为2.70 N,土钵基质损失率为2.94%,利于茄子钵苗的全自动机械化移栽。根据移栽机构数学模型结合茄子钵苗农艺要求,开发了牛顿插值齿轮茄子钵苗移栽机构优化设计与分析软件,优化出一组满足茄子钵苗移栽要求的参数。根据优化的参数进行三维建模、虚拟仿真,运用3D打印技术制作物理样机进行了轨迹验证试验,验证了该机构的正确性与可行性,通过取苗试验与栽植试验,证明了该机构的实用性。

关键词：茄子钵苗移栽机构牛顿插值齿轮参数优化正交试验

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不同股市情绪下机构投资者与股市稳定性研究

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浙江科技学院学报 2021年第2期33卷 123-130,143页

作者：张萍周羿吟浙江科技学院经济与管理学院杭州310023

为研究机构投资者对股市稳定性的作用,以证券投资基金为机构投资者代表,引入股权分置改革和深化体制改革作为中国股市两大情绪转换期的分隔点,利用主成分分析法得出个人投资者情绪指数,使用EGARCH模型(exponential generalized autoregr... 详细信息

为研究机构投资者对股市稳定性的作用,以证券投资基金为机构投资者代表,引入股权分置改革和深化体制改革作为中国股市两大情绪转换期的分隔点,利用主成分分析法得出个人投资者情绪指数,使用EGARCH模型(exponential generalized autoregressive conditional heteroskedasticity model,指数广义自回归条件异方差模型)实证研究在不同股市情绪下机构投资者对股市波动性及个人投资者的影响。结果表明:在股权分置改革时期,机构投资者行为系数η1小于0,杠杆指标β大于0,交互项显著,表明机构投资者减弱了股市波动性,且存在正杠杆作用,此时机构投资者对个人投资者影响较大;在情绪平淡期,η1值远小于0,个人投资者指标十分显著,表明机构投资者对股市波动性和个人投资者的正向影响最大;在深化体制改革时期η1的估计值为30.216,此时交互项不显著,表明此时机构投资者加剧了股市波动,但对个人投资者的影响作用不大。可见,机构投资者并不能在任何时候都起到稳定股市的作用,也不能对个人投资者行为起到持续的正向影响,因此监管当局需根据不同股市情绪灵活制定相应政策。

关键词：机构投资者股市情绪 EGARCH模型主成分分析

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Electrically injected GeSn lasers with peak wavelength up to 2.7 μm

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Photonics Research 2022年第1期10卷 222-229页

作者： yiyin zhou SOLOMON OJO CHEN-WEI WU YUANHAO MIAO HUONG TRAN JOSHUA MGRANT GREY ABERNATHY SYLVESTER AMOAH JAKE BASS GREGORY SALAMO WEI DU GUO-EN CHANG JIFENG LIU JOE MARGETIS JOHN TOLLE YONG-HANG ZHANG GREG SUN RICHARD ASOREF BAOHUA LI SHUI-QING YU Department of Electrical Engineering University of ArkansasFayettevilleArkansas 72701USA Microelectronics-Photonics Program University of ArkansasFayettevilleArkansas 72701USA Department of Mechanical Engineering Taiwan Chung-Cheng UniversityMing-HsiungChiayi 62102China Department of Physics University of ArkansasFayettevilleArkansas 72701USA Institute for Nanoscience and Engineering University of ArkansasFayettevilleArkansas 72701USA Department of Electrical Engineering and Physics Wilkes UniversityWilkes-BarrePennsylvania 18766USA Thayer School of Engineering Dartmouth CollegeHanoverNew Hampshire 03755USA School of Electrical Energy and Computer EngineeringArizona State UniversityTempeArizona 85287USA Department of Electrical Engineering University of Massachusetts BostonBostonMassachusetts 02125USA Arktonics LLCFayettevilleArkansas 72701USA

GeSn lasers enable the monolithic integration of lasers on the Si platform using all-group-Ⅳ direct-bandgap *** GeSn laser study recently moved from optical pumping into electrical *** this work,we present explorative investigations of GeSn heterostructure laser diodes with various layer thicknesses and material *** layer material was studied by using Si_(0.03)Ge_(0.89)Sn_(0.08) and Ge_(0.95)Sn_(0.05),and cap layer total thickness was also *** 190 nm SiGeSn-cap device had threshold of 0.6 kA/cm^(2) at 10 K and a maximum operating temperature(T_(max)) of 100 K,compared to 1.4 kA/cm^(2) and 50 K from 150 nm SiGeSn-cap device,***,the 220 nm GeSn-cap device had 10 K threshold at 2.4 kA/cm^(2) and T_(max) at 90 K,i.e.,higher threshold and lower maximal operation temperature compared to the SiGeSn cap layer,indicating that enhanced electron confinement using SiGeSn can reduce the threshold *** study of the active region material showed that device gain region using Ge_(0.87)Sn_(0.13) had a higher threshold and lower T_(max),compared to Ge_(0.89)Sn_(0.11).The performance was affected by the metal absorption,free carrier absorption,and possibly defect density *** maximum peak wavelength was measured as 2682 nm at 90 K by using Ge_(0.87)Sn_(0.13) in gain *** investigations provide directions to the future GeSn laser diode designs toward the full integration of group-Ⅳ photonics on a Si platform.

关键词： GeSn pumping absorption

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Microstructure and Wear/corrosion Resistance of Stainless Steel Laser-alloyed with Mn+W_(2)C, Mn+NiWC and Mn+SiC

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 283-294页

作者： zhou Rui DIAO Xiaogang SUN Yixin School of Metallurgical Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China CITIC Heavy Cast Iron Industry Co. Ltd.Luoyang 417039China

In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed *** evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were *** indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+*** as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C *** improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.

关键词： laser surface alloying stainless steel carbide type microstructure wear and corrosion resistance

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Distributed fiber optic sensing system for vibration monitoring of 3D printed bridges

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Optoelectronics Letters 2025年第1期21卷 28-34页

作者： ZHAO Shuai zhou Ran LUO Mingming LIU Jianfei LIU Xiongfei zhou Tao School of Electronic Information Engineering Hebei University of Technology Tianjin Key Laboratory of Electronic Materials and Devices School of Civil Engineering and Transportation Hebei University of Technology Tianjin Jinhang Institute of Technical Physics

The fiber optic sensing technology provides data support in structural health monitoring of the macro facilities, including design, construction, and maintenance of bridges, tunnels, ports and other infrastructures. In this paper, a distributed vibration sensing system is proved to be responsive to a single touch over a 1.8-m-long equivalent fiber segment, covering a vibration frequency from 5 Hz to 25 kHz. The sensing fiber was arranged as an S type layout on the bridge to recognize the standing state, windblown disturbance, and walking vibration. Moreover, the knocking and climbing events are recognized fiber laying spinning lines and hanging on the fences, respectively. The demonstration shows an accurate positioning and sensitive vibration monitoring applied on the automated three-dimensional(3D) printed bridge, which is applicable to all kinds of 3D printed facilities as intelligent sensory neuro-networks.

关键词： Spinning (fibers)

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Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： Jian‑En zhou Yilin Li Xiaoming Lin Jiaye Ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Lithium-ion batteries(LIBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with Li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(LIBs,SIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues Self-sacrificial template Lithium-ion batteries Sodium-ion batteries Potassium-ion batteries

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Grid-Connected/Islanded Switching Control Strategy for Photovoltaic Storage Hybrid Inverters Based on Modified Chimpanzee Optimization Algorithm

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Energy Engineering 2025年第1期122卷 265-284页

作者： Chao zhou NarisuWang Fuyin Ni Wenchao Zhang School of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou213001China Jiangsu Key Laboratory of Power Transmission&Distribution Equipment Technology Jiangsu University of TechnologyChangzhou213001China

Uneven power distribution,transient voltage,and frequency deviations are observed in the photovoltaic storage hybrid inverter during the switching between grid-connected and island *** response to these issues,this paper proposes a grid-connected/island switching control strategy for photovoltaic storage hybrid inverters based on the modified chimpanzee optimization *** proposed strategy incorporates coupling compensation and power differentiation elements based on the traditional droop ***,it combines the angular frequency and voltage amplitude adjustments provided by the phase-locked loop-free pre-synchronization control *** pre-synchronization is achieved by regulating the virtual current to zero and aligning the photovoltaic storage hybrid inverter with the grid ***,two novel operators,learning and emotional behaviors are introduced to enhance the optimization precision of the chimpanzee *** operators ensure high-precision and high-reliability optimization of the droop control parameters for photovoltaic storage hybrid inverters.A Simulink model was constructed for simulation analysis,which validated the optimized control strategy’s ability to evenly distribute power under load *** strategy effectively mitigated transient voltage and current surges during mode ***,seamless and efficient switching between gridconnected and island modes was achieved for the photovoltaic storage hybrid *** enhanced energy utilization efficiency,in turn,offers robust technical support for grid stability.

关键词： Photovoltaic storage hybrid inverters modified chimpanzee optimization algorithm droop control seamless switching

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Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao zhou Xiongbin Luo Hang Li Shan Guo Zhuang Tong Xiaotao zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Solvation

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Laser‑Induced Highly Stable Conductive Hydrogels for Robust Bioelectronics

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Nano-Micro Letters 2025年第3期17卷 117-120页

作者： Yibo Li Hao zhou Huayong Yang Kaichen Xu State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310058People’s Republic of China

Despite the promising progress in conductive hydrogels made with pure conducting polymer,great challenges remain in the interface adhesion and robustness in longterm *** address these challenges,*** Hwan Ko and Taek-Soo Kim’s team introduced a laserinduced phase separation and adhesion method for fabricating conductive hydrogels consisting of pure poly(3,4-ethylenedioxythiophene):polystyrene sulfonate on polymer *** laser-induced phase separation and adhesion treated conducting polymers can be selectively transformed into conductive hydrogels that exhibit wet conductivities of 101.4 S cm^(−1)with a spatial resolution down to 5μ***,they maintain impedance and charge-storage capacity even after 1 h of *** micropatterned electrode arrays demonstrate their potential in long-term in vivo signal recordings,highlighting their promising role in the field of bioelectronics.

关键词： Laser processing Conductive hydrogels Stable interface Bio-interfacing electrodes Bioelectronic application

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