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Mechanical analysis of C/C composite grids in ion optical system

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Applied Mathematics and Mechanics(English Edition) 2019年第11期40卷 1589-1600页

作者： Shuiqiang zhang Aijun LI Yuqin ZHENG dongsheng zhang School of Engineering Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072China Research Center for Composite Materials Shanghai UniversityShanghai 200444China Department of Mechanics Shanghai UniversityShanghai 200444China

The ion thruster is an engine with high specific impulse for satellites and spacecrafts,which uses electric energy to boost the *** ion optical system,also known as gate assemblies which consist of acceleration and screen grids,is the key component of the ion *** this paper,the static mechanical properties of the C/C composite grids are evaluated based on the structural *** volume element (RVE) is adopted to simplify the braded composite structure as a continuum *** dynamical behavior of the 100 mm ion thruster optics in the launch environment (1000g shock-load) is numerically modeled and simulated with the half-sine pulse *** impact response of the C/C and molybdenum gate assemblies on the stress distribution and deformation is *** simulated results indicate that the magnitudes of the normal displacement of the composite grids subject to the uniformly distributed load are on the same level as molybdenum grids although the normal stiffness of the composite grids is much *** subject to impact loading,the stress distribution in the C/C composite grids is similar to molybdenum grids while the stress magnitude is much *** finding shows that the C/C gate assemblies outperform molybdenum grids and meet the requirement of long lifetime service in space travel.

关键词： ion optical system C/C composite grid mechanical analysis

Benthodytes occidentpalauta ***.,a new species of deep-sea holothuroid(Elasipodida:Psychropotidae)from the west of Kyushu-Palau Ridge in the Western Pacific Ocean

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Journal of Oceanology and Limnology 2024年第1期42卷 252-262页

作者： Chongzhen YUAN Chunsheng WANG dongsheng zhang Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China

Benthodytes occidentpalauta *** collected from the Kyushu-Palau Ridge at a depth of 5481 m in *** new species is characterized by a gelatinous body wall,violet skin,six pairs of dorsal papillae,and a rough mid-ventral surface without tube *** dorsal deposits are rod-shaped and *** types of papillae deposits as crosses with four arms with central bipartite *** deposits are *** ossicles are rod-shaped with end *** deposits are rodshaped,tripartite,and *** phylogenetic analyses based on cytochrome oxidase subunit 1(COI)and 16S individually and a concatenated dataset of COI and 16S genes of this species support that *** *** to Benthodytes.

关键词： Holothuroidea Benthodytes cytochrome oxidase subunit 1(COI) 16S phylogenetic analysis

A new tunable elastic metamaterial structure for manipulating band gaps/wave propagation

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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1543-1554页

作者： Zhenyu WANG Zhaoyang MA Xingming GUO dongsheng zhang Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai UniversityShanghai 200444China

A one-dimensional mechanical lattice system with local resonators is proposed as an elastic metamaterial model,which shows negative mass and negative modulus under specific frequency *** proposed representative units,consisting of accurately arranged rigid components,can generate controllable translational resonance and achieve negative mass and negative modulus by adjusting the local structural parameters.A shape memory polymer is adopted as a spring component,whose Young’s modulus is obviously affected by temperature,and the proposed metamaterials’tunable ability is achieved by adjusting *** effect of the shape memory polymer’s stiffness variation on the band gaps is investigated detailedly,and the special phenomenon of intersecting dispersion curves is discussed,which can be designed and controlled by adjusting *** dispersion relationship of the continuum metamaterial model affected by temperature is obtained,which shows great tunable ability to manipulate wave propagation.

关键词： tunable elastic metamaterial negative mass negative modulus

Vibration isolation performance analysis of a bilateral supported bio-inspired anti-vibration control system

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Applied Mathematics and Mechanics(English Edition) 2023年第5期44卷 759-772页

作者： Shihua ZHOU dongsheng zhang Bowen HOU Zhaohui REN School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China

To achieve better anti-vibration performance in a low frequency region and expand the range of vibration isolation,a bilateral supported bio-inspired anti-vibration(BBAV)structure composed of purely linear elements is proposed,inspired by the motion form of bird legs and the nonlinear extension and compression of muscles and *** kinematic relations and nonlinear dynamic model considering vertical and rotational vibrations are *** loading capacity and equivalent stiffness are investigated with key *** amplitude-frequency characteristics and force transmissibility are used to evaluate the stability and anti-vibration performance with the effects of the excitation amplitude,rod length,installation angle,and spring *** results show that the loading requirements and resonant characteristics of the BBAV structure are adjustable,and superior vibration isolation performance can be achieved readily by tuning the *** X-shaped vibration structure is sensitive to the spring stiffness,which exhibits a wider vibration isolation bandwidth with smaller spring ***,depending on the parameters,the nonlinear behavior of the BBAV system can be interconverted between the softening type and the hardening *** theoretical analysis in this study demonstrates the advantages and effectiveness of the vibration isolation structure.

关键词： bio-inspired X-shaped structure anti-vibration performance force transmissibility loading capacity amplitude-frequency curve

Different vertical distribution of zooplankton community between North Pacific Subtropical Gyre and Western Pacific Warm Pool: its implication to carbon flux

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Acta Oceanologica Sinica 2019年第6期38卷 32-45页

作者： Dong Sun dongsheng zhang Ruiyan zhang Chunsheng Wang Key Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic AdministrationHangzhou 310012China Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

The mesozooplankton in both epipelagic and mesopelagic zones is essentially important for the study of ecosystem and biological carbon pump. Previous studies showed that the diel vertical migration (DVM) pattern of mesozooplankton varied among ecosystems. However, that pattern was largely unknown in the Western Pacific Warm Pool (WPWP). The vertical distribution, DVM and community structure of mesozooplankton from the surface to 1 000 m were compared at Stas JL7K (WPWP) and MA (North Pacific Subtropical Gyre, NPSG). Two sites showed similarly low biomass in both epipelagic and mesopelagic zones, which were in accordance with oligotrophic conditions of these two ecosystems. Stronger DVM (night/day ratio) was found at JL7K (1.31) than that at MA (1.09) on surface 0–100 m, and an obvious night increase of mesopelagic biomass was observed at JL7K, which was probably due to migrators from bathypelagic zone. Active carbon flux by DVM of zooplankton was estimated to be 0.23 mmol/(m2·d) at JL7K and 0.16 mmol/(m2·d) at MA. The community structure analysis showed that calanoid copepods, cnidarians and appendicularians were the main contributors to DVM of mesozooplankton at both sites. We also compared the present result with previous studies of the two ecosystems, and suggested that the DVM of mesozooplankton was more homogeneous within the WPWP and more variable within the NPSG, though both ecosystems showed typically extremely oligotrophic conditions. The different diel vertical migration strength of mesozooplankton between NPSG and WPWP implied different efficiency of carbon pump in these two ecosystems.

关键词： mesopelagic zone diel vertical migration biological pump vertical distribution active carbon flux

Quality evaluation of rubber-to-metal bonded structures based on shearography

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Science China(Physics,Mechanics & Astronomy) 2015年第7期58卷 49-56页

作者： LIU Bin GUO XingMing QI GongJin zhang dongsheng Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Beijing Aeronautical Technology Research Center Department of Mechanics Shanghai University

The quality of bonding is often a concern in rubber-to-metal bonded parts with regard to the integrity and stability of the structure. In this study, shearography has been used to detect the out-of-plane deformation of the defects caused by thermal and vacuum stresses. A sample of the vulcanized styrene-butadiene rubber bonded to steel with known artificial voids was prepared and during bonding process a region was glued with thick adhesives. The rubber surface of the sample was inspected in thermal radiation and vacuum modes respectively with a self-designed shearography device. Meanwhile, a numerical simulation was conducted to predict the out-of-plane deformation of the rubber surface in these two stress modes. Results from the numerical simulation and the experiments indicated that the debonding defects could be inspected in both loading modes. In the thermal radiation mode the region with thick adhesives could be identified successfully. This study provides a guideline for quality control of rubber-to-metal structures using an optical method.

关键词： shearography optical mechanics debonding

Digital monitoring for heavy duty mechanical equipment based on fiber Bragg grating sensor

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Science China(Technological Sciences) 2009年第2期52卷 285-293页

作者： ZHOU ZuDe JIANG DeSheng zhang dongsheng School of Mechatronics Engineering Wuhan University of TechnologyHubei 430070China Key Laboratory of Fiber Optic Sensing Technology and Information Processing(Wuhan University of Technology) Ministry of EducationHubei 430070China

The digital monitoring principle and technologies for heavy duty mechanical equipment based on fiber Bragg grating (FBG) technology are introduced in this paper. The fundamentals of new-style FBG sensing technology, including the photorefractive effect of FBG, the physical formation, and the relation between optical properties and grating parameters, are investigated. The plaster, encapsulation and distribution planning of FBG sensor (FBGS), which is used to monitor heavy duty mechanical equipment under abominable environment and extreme conditions, are also studied. In addition, theoretical and experimental researches on the strain, temperature, displacement, and stress transmission characteristics between FBGS and detection interface are presented. The principle and method for temperature compensation in non-uniformity temperature field are described in detail as well. Comparing with the traditional sensing monitoring techniques, the application of FBGS technology on digital monitoring and diagnosis for heavy duty mechanical equipment has a number of significant technical advantages and will make a new breakthrough in this field.

关键词： fiber Bragg grating sensor (FBGS) heavy duty mechanical equipment digital monitoring temperature compensation

Benthodytes palauta,a new species of deep-sea holothuroid(Elasipodida:Psychropotidae)from the western Pacific Ocean

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Acta Oceanologica Sinica 2021年第12期40卷 50-54页

作者： Chuan Yu Chunsheng Wang dongsheng zhang Ruiyan zhang School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

A new species of Psychropotidae holothuroid,Benthodytes palauta ***.,was collected from the Kyushu-Palau Ridge at a depth of 2666 *** new species is characterized by a leathery body wall,red-violet skin,five pairs of dorsal papillae,nineteen pairs of tube feet,and a narrow *** internal organs include one Polian vesicle,two tufts of gonads,and no respiratory *** ossicles are large and spinous,with crosses of four arms with central bipartite *** ossicles are crosses with four arms with bipartite *** dorsal ossicles were few and large,and cross-shaped with four arms and central bipartite *** ossicles were large and rod-shaped or slender *** ossicles were primary crosses of four arms and brim ossicles were cross-shaped with *** phylogenetic analyses of this species support that *** *** to ***,the paraphyletic relationships were confirmed;however,a revision of the genus Benthodytes is needed to resolve its phylogenetic relationship.

关键词： 16S COI Kyushu-Palau Ridge phylogenetic analyses Psychropotes Psycheotrephes

Design of comprehensive test system for detecting overlying strata mining-induced fractures on surface with radon gas

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Mining Science and Technology 2011年第6期21卷 823-827页

作者： zhang Wei zhang dongsheng Fan Gangwei State Key Laboratory of Coal Resources and Safe Mining School of Mines China University of Mining ＆ Technology Xuzhou 211116 China College of Geology and Exploration Engineering Xinjiang University Urumchi 830046 China

Based on radon gas properties and its existing projects applications, we firstly attempted to apply geo- physical and chemical properties of radon gas in the field of mining engineering, and imported radioac- tive measurement method to detect the development process of the overlying strata mining-induced fractures and their contained water quality in underground coal mining, which not only innovates a more simple-fast-reliable detection method, but also further expands the applications of radon gas detection technology in mining field. A 3D simulation design of comprehensive testing system for detecting strata mining-induced fractures on surface with radon gas (CTSR) was carried out by using a large-scale 3D solid model design software Pro/Engineer (Pro/E), which overcame three main disadvantages of ''static design thought, 2D planar design and heavy workload for remodification design'' on exiting design for mining engineering test systems. Meanwhile, based on the simulation design results of Pro/E software, the sta- bility of the jack-screw pressure bar for the key component in CTSR was checked with a material mechan- ics theory, which provided a reliable basis for materials selection during the latter machining process.

关键词： Mining engineering Radon gas detection technology Mining-induced fractures Comprehensive test system Pro/Engineer 3D simulation