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塔额盆地草原蝗虫空间生态位研究

环境昆虫学报 2024年第3期46卷 625-634页

作者：宋占云万育欣查绪栋陈冉杨静 ROMAN Jashenko 季荣新疆师范大学生命科学学院新疆特殊环境物种保护与调控生物学实验室中亚区域跨境有害生物联合控制国际研究中心乌鲁木齐830054 哈萨克斯坦科学院动物研究所阿拉木图050038

本文分析塔额盆地草原蝗虫的生态位,旨在为当地的蝗灾监控、治理及生态平衡保护提供理论依据。本研究对塔额盆地冲积平原、山前洪积倾斜平原、山地3种地形的草原蝗虫的空间生态位进行分析,统计得出了蝗虫优势度、群落组成差异、Levins... 详细信息

本文分析塔额盆地草原蝗虫的生态位,旨在为当地的蝗灾监控、治理及生态平衡保护提供理论依据。本研究对塔额盆地冲积平原、山前洪积倾斜平原、山地3种地形的草原蝗虫的空间生态位进行分析,统计得出了蝗虫优势度、群落组成差异、Levins生态位宽度和Shannon生态位宽度、Pianka生态位重叠等相关参数。结果表明:3种地形共采集蝗虫6科19种1023头,不同地形优势种、常见种及稀有种均存在差异。山地与山前洪积倾斜平原、冲积平原的蝗虫群落组成差异较大。黑条小车蝗Oedaleus decorus decorus、蓝胫戟纹蝗Dociostaurus tartarus、意大利蝗Calliptamus italicus、红胫戟纹蝗Dociostaurus kraussi kraussi、伪星翅蝗Calliptamus coelesyriensis的生态位较宽且与其他蝗虫存在生态位重叠。塔额盆地草原蝗虫发生种类较多,绝大部分优势种蝗虫对空间资源的利用能力较强、竞争较激烈,对优势危害种加大监测力度,而针对山前洪积倾斜平原中的稀有种类,应加以保护以确保生物多样性。

关键词：塔额盆地生态位宽度生态位重叠草原蝗虫

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Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm

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Defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： Guangbo xu Bingting zha Hailu Yuan Zhen Zheng He zhang Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

Seabed structures and foundations related to deep-sea resource development:A review based on design and research

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Deep Underground Science and Engineering 2024年第2期3卷 131-148页

作者： Shengjie Rui Haojie zhang Hang xu Xing zha Mengtao xu Kanmin Shen Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhouChina Advanced Modelling Offshore EnergyNorwegian Geotechnical InstituteOsloNorway Geotechnical Technology Center(Overseas Engineering Center) PowerChina Huadong Engineering Corporation LimitedHangzhouChina

The deep‐sea ground contains a huge amount of energy and mineral resources,for example,oil,gas,and *** infrastructures such as floating structures,seabed structures,and foundations have been developed to exploit these *** seabed structures and foundations can be mainly classified into three types:subsea production structures,offshore pipelines,and *** study reviewed the development,installation,and operation of these infrastructures,including their structures,design,installation,marine environment loads,and *** this basis,the research gaps and further research directions were explored through this literature ***,different floating structures were briefly analyzed and reviewed to introduce the design requirements of the seabed structures and ***,the subsea production structures,including subsea manifolds and their foundations,were reviewed and ***,the basic characteristics and design methods of deep‐sea pipelines,including subsea pipelines and risers,were analyzed and ***,the installation and bearing capacity of deep‐sea subsea anchors and seabed trench influence on the anchor were *** the review,it was found that marine environment conditions are the key inputs for any offshore structure *** fabrication,installation,and operation of infrastructures should carefully consider the marine loads and geological *** structures have their own mechanical *** fatigue and stability of pipelines mainly depend on the soil‐structure *** selection should consider soil types and possible trench *** focuses and research gaps can provide a helpful guide on further research,installation,and operation of deep‐sea structures and foundations.

关键词： anchors floating structures pipelines risers subsea foundations

NONLINEAR VIBRATION FOR MODERATE THICKNESS RECTANGULAR CRACKED PLATES INCLUDING COUPLED EFFECT OF ELASTIC FOUNDATION

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Applied Mathematics and Mechanics(English Edition) 2005年第8期26卷 963-972页

作者： XIAO Yong-gang（肖勇刚） FU Yi-ming（傅衣铭） zha xu-dong（查旭东） Department of Engineering Mechanics Hunan UniversityChangsha 410082 P. R. China College of Bridge and Structure Engineering Changsha University of Science and Technology Changsha 410076 P. R. China

Based on Reissner plate theory and Hamilton variational principle, the nonlinear equations of motion were derived for the moderate thickness rectangular plates with transverse surface penetrating crack on the two-parameter foundation. Under the condition of free boundary, a set of trial functions satisfying all boundary conditions and crack＇s continuous conditions were proposed. By employing the Galerkin method and the harmonic balance method, the nonlinear vibration equations were solved and the nonlinear vibration behaviors of the plate were analyzed. In numerical computation, the effects of the different location and depth of crack, the different structural parameters of plates and the different physical parameters of foundation on the nonlinear amplitude frequency response curves of the plate were discussed.

关键词： moderate thickness rectangular plate elastic foundation crack nonlinear vibration

Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： Jun zha Huijie zhang School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

Chiral transfer amidst one-dimensional linear polymers and twodimensional network covalent organic frameworks:Striking a fine balance between helicity and crystallinity

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Nano Research 2024年第6期17卷 5726-5734页

作者： Xinlin zha Mengjuan Zuo Guilin xu Zhong Yan Haining You Yi Xiong Ying Liu Yingying Li Liyan Yang Ke Liu Mufang Li Tao zhao dong Wang College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China Key Laboratory of Textile Fiber and Products Ministry of EducationWuhan Textile UniversityWuhan 430200China

The current landscape of chiral covalent organic frameworks(COFs)predominantly centered on constructing asymmetric molecular-scale chirality,often introducing an inherent contradiction to the COF symmetry and limiting ***,we overcome these challenges by achieving chiral transfer between one-dimensional(1D)imine linear polymers(LPs)and two-dimensional(2D)networkβ-ketoenamine COFs composed of achiral *** successfully synthesize several 1D imine LPs with mesoscopic helical chirality,comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription *** the irreversible tautomerism mechanism within the linker replacement approach,terephthalaldehyde(TPA)units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol(TP),yielding the corresponding 2D networkβ-ketoenamine *** and helicity of the resultantβ-ketoenamine COFs intimately hinge on reaction conditions,including the aldehyde stoichiometry of Tp and TPA,as well as the quantity and concentration of the catalyst *** optimized conditions,the nucleation and growth were precisely governed,achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D networkβ-ketoenamine COFs,even with covalent bond rupture,recombination,and topological transition(from[C2+C2]to[C3+C2]).Impressively,the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D networkβ-ketoenamine *** study not only offers new perspectives on the development of chiral functional COFs,but also provides fresh insights into the precise control of COFs'microscopic morphology.

关键词： chiral covalent organic frameworks chiral transfer dimensional transformation helicity

Molecular Dynamics-Based Simulation of Polyethylene Pipe Degradation in High Temperature and High Pressure Conditions

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2139-2161页

作者： Guowei Feng Qing Li Yang Wang Nan Lin Sixi zha Hang dong Ping Chen Minjun Zheng School of Mechanical Engineering Xinjiang UniversityUrumqi830046China Xinjiang Yian Special Inspection Engineering Company Limited Urumqi830063China Xinjiang Uygur Autonomous Region Inspection Institute of Special Equipment Urumqi830000China Pressure Pipe Department China Special Equipment Inspection and Research InstituteBeijing100013China Tarim Oilfield Branch Company Korla841000China Yimai Cai Oil and Gas Management Area Tarim Oilfield Branch OfficeKorla841000China

High-density polyethylene(HDPE)pipes have gradually become the first choice for gas networks because of their excellent *** the use of pipes increases,there will unavoidably be a significant amount of waste generated when the pipes cease their operation life,which,if improperly handled,might result in major environmental contamination *** this study,the thermal degradation of polyethylene materials is simulated for different pressures(10,50,100,and 150 MPa)and temperatures(2300,2500,2700,and 2900 K)in the framework of Reactive Force Field(ReaxFF)molecular dynamics *** main gas products,density,energy,and the mean square displacement with temperature and pressure are also *** findings indicate that raising the temperature leads to an increase in the production of gas products,while changing the pressure has an impact on the direction in which the products are generated;the faster the temperature drops,the less dense the air;both temperature and pressure increase impact the system’s energy conversion or distribution mechanism,changing the system’s potential energy as well as its total energy;the rate at which molecules diffuse increases with temperature,and decreases with *** results of this investigation provide a theoretical basis for the development of the pyrolytic treatment of polyethylene waste materials.

关键词： ReaxFF MD high-density polyethylene degradation temperature pressure

Polydopamine-modified metal-organic frameworks nanoparticles enhance the corrosion resistance and bioactivity of polycaprolactone coating on high-purity magnesium

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Journal of Magnesium and Alloys 2024年第5期12卷 2070-2089页

作者： Qingyun Fu Shaojie He Junjie Yang Ziyu Su Ping Li Xincheng Yu Weihong Jin Shulan xu Zhentao Yu Dingsheng zha Center of Oral Implantology Stomatological HospitalSouthern Medical UniversityGuangzhouChina Panyu Hospital of Chinese Medicine Guangzhou 511400China Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China First Affiliated Hospital of Jinan University Guangzhou 510630China

Biodegradable magnesium(Mg)and its alloys exhibit excellent biocompatibility and mechanical compatibility,demonstrating tremendous potential for applications in ***,the rapid degradation rate has limited their clinical ***(PCL)is commonly employed as a polymer coating to impede the rapid degradation of ***,its long-term anti-corrosion capability and bioactivity are *** address these issues,polydopamine(PDA)-modified zeolitic imidazolate framework-8(PZIF-8)bioactive nanoparticles are fabricated and incorporated into the PCL *** PZIF-8 particles,featuring catechol motifs,can enhance the compactness of the PCL coating,reduce its defects,and possess biomineralization ability,thereby effectively improving its anti-corrosive and bioactive ***,the active substances released from the degradation of the PZIF-8 particles such as Zn^(2+)and PDA are beneficial for *** corrosion tests indicate that the corrosion current density of PCL-treated sample decreases by more than one order of magnitude and the amount of H_(2)released decreases from 0.23±0.12 to 0.08±0.08 ml cm^(-2)after doping with the ***,the improved corrosion resistance and released PDA and Zn^(2+)from the coating can promote osteogenic differentiation by up-regulating the expression of alkaline phosphatase activity,related osteogenic genes,and *** addition,in vivo implantation experiments in rabbit femur defects further offer strong evidence that the doping of PZIF-8 nanoparticles accelerates bone reconstruction of the PCL *** summary,this work implies a new strategy to fabricate a PCL-based coating on Mg-based implants by introducing the PZIF-8 particles for orthopedic applications.

关键词： Polydopamine ZIF-8 High-purity magnesium Polycaprolactone coating Anticorrosion Bone regeneration

Preparing cyclic polymers at high concentrations via self-folding cyclization technique by adjusting the contents of hydrophilic units in linear precursors

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Chinese Chemical Letters 2024年第2期35卷 283-288页

作者： Hao zha Zuowei Wang Chao Liu Chunyan Hong Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Cyclic polymers are a class of polymers that feature endless topology,and the synthesis of cyclic polymers has attracted the attention of many ***,cyclic polymers were efficiently constructed by self-folding cyclization technique at high *** poly((oligo(ethylene glycol)acrylate)-co-(dodecyl acrylate))(P(OEGA-co-DDA))precursors with different ratios of hydrophilic and hydrophobic moieties were synthesized by reversible addition-fragmentation chain transfer(RAFT)polymerization using a bifunctional chain transfer agent with two anthryl end *** amphiphilic linear precursors underwent the self-folding process to generate polymeric nanoparticles in *** irradiating the aqueous solution of the nanoparticles with 365 nm UV light,cyclic polymers were synthesized successfully via coupling of anthryl *** effects of the ratios of hydrophilic and hydrophobic moieties in linear P(OEGA-co-DDA)copolymers and polymer concentration on the purity of the obtained cyclic polymers were explored in detail via ^(1)H nuclear magnetic resonance(^(1)H NMR),dynamic light scattering(DLS),UV‒visible(vis)analysis,three-detection size exclusion chromatography(TD-SEC)and transmission electron microscopy(TEM).It was found that by adjusting the content of the hydrophilic segments in linear precursors,single chain polymeric nanoparticles(SCPNs)can be generated at high polymer ***,cyclic polymers with high purity can be constructed *** method overcomes the limitation of traditional ring-closure method,which is typically conducted in highly dilute conditions,providing an efficient method for the scalable preparation of cyclic polymers.

关键词： Cyclic polymers Self-folding cyclization technique Single chain polymeric nanoparticles RAFT polymerization Direct visualization