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REPRODUCTIVE MECHANISM OF RUDITAPES PHILIPPINARUM PHYSIOLOGICAL ACTION OF NH4OH SEAWATER AND THE DISCOVERY OF SHEDDING HORMONE

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Acta Oceanologica Sinica 1983年第2期 320-329页

作者：方永强汪敏 Third Institute of Oceanography National Bureau of Oceanography Xiamen

This paper expounds primarily on the physiological mechanism of the mature process and release of Ruditapes philippinarum’s eggs. A natural dry condition, immersion in NH4OH seawater, and crude extracted shedding hormone, were the necessary physiological conditions and factors which make eggs reach physiological maturity, and make the female or male clam spaw and spermiate. At the same time, it has been shown that the physiological action of the NH4OH seawater may stimulate the respiration of the eggs, and that the comsumption oxygen raises 15.17*1. The shape of eggs turns from oval into round; and the ultrastructure of the nucleus and cytoplasm show strengthened metabolic activity. Besides, it has been substantiated that the shedding hormone exist in the gonad of female clams. The shedding hormone may be a heat labile protein. The result may be of theoretial importance and economic value to artifical reproduction of the molluscs.

关键词： OH REPRODUCTIVE MECHANISM OF RUDITAPES PHILIPPINARUM PHYSIOLOGICAL ACTION OF NH4OH SEAWATER AND THE DISCOVERY OF SHEDDING HORMONE NH

Improving Fatigue Properties of 316L Stainless Steel Welded Joints by Surface Spinning Strengthening

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 840-854页

作者： Dongqiqiong wang Qiang wang Xiaowu Li Zhefeng Zhang Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China College of Light Industry Liaoning UniversityShenyang 110036China

The surface spinning strengthening(3S)mechanism and fatigue life extension mechanism of 316L stainless steel welded joint were systematically elucidated by microstructural analyses and mechanical *** indicate that surface gradient hardening layer of approximately 1 mm is formed in the base material through grain fragmentation and deformation twin strengthening,as well as in the welding zone composed of deformedδ-phases and *** fatigue strength of welded joint after 3S significantly rises by 32%(from 190 to 250 MPa),which is attributed to the effective elimination of surface geometric defects,discrete refinement ofδ-Fe phases and the appropriate improvement in the surface strength,collectively mitigating strain localization and surface fatigue damage within the gradient strengthening *** redistributed fineδ-Fe phases benefited by strong stress transfer of 3S reduce the risk of surface weak phase cracking,causing the fatigue fracture to transition from microstructure defects to crystal defects dominated by slip,further suppressing the initiation and early propagation of fatigue cracks.

关键词： 316L stainless steel Welded joint Surface spinning strengthening Nanotwin Fatigue life

Numerical Analysis on Charging Performance of the Macro-Encapsulating Combined Sensible-Latent Heat Storage System with Structural Parameters

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Journal of Thermal Science 2024年第3期33卷 1026-1036页

作者： wang Wei PAN Zhenfei wang Jingfu WU Yuting MA Chongfang Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of EducationCollege of Energy and Power EngineeringBeijing University of TechnologyBeijing100124China Key Laboratory of Heat Transfer and Energy Conversion Beijing MunicipalityCollege of Energy and Power EngineeringBeijing University of TechnologyBeijing100124China

For combined sensible-latent heat storage system(CSLHS)(termed as the hybrid configuration),macro encapsulation can effectively solve the leakage problem of ***,due to the poor thermal conductivity of PCMs,the charging performance of the hybrid configuration slightly increases compared to the solid structure(with only sensible materials).Meanwhile,the natural convection in the PCMs zone could improve the charging ***,how to improve natural convection intensity is a key issue for the CSLHS by macro *** is found that adding fins can significantly enhance natural convection and accelerate the melting of *** this paper,we proposed the hybrid configuration with fins built-in by macro encapsulation,and analyzed its charging performance with different fin structural parameters in the PCM zone by CFD *** the case,the sensible heat storage material is high-temperature concrete and the PCM is a low-melting-point mixed molten *** analyzed the effects of fin number,fin length and fin thickness on the charging performance of the hybrid configuration *** the result,the charging performance increases with the fin number,but the increase rate gradually *** the fin number is 6,the charging performance increases by 20.18%compared to the situation without *** charging performance increases gradually with the fin *** with the hybrid configuration without fin,for each 10 mm increase in fin length,its charging performances increase by 4.09%,5.26%,7.02%,8.77%,11.70%,and 15.79%,*** from number and length of fins,the effect of thickness on the charging performance is very *** the fin thickness increased from 1 mm to 4 mm,the charging performance only increased by 2.3%.It indicates that the main reason for the improving the charging performance is to increase the natural convection intensity by dividing the PCM zone through *** results show that the charging performance

关键词： macro-encapsulation hybrid configuration natural convection structural parameter charging performance

Numerical simulation and parameter optimization of Coriolis force scale measurement process based on DEM

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Particuology 2024年第7期90卷 128-139页

作者： Haiting Liu Yong Yang Xiangliang wang Jiewen Deng Bingbing wang School of Energy and Power Engineering Northeast Electric Power UniversityJilin132012China CNBM Hefei Mechanical&Electrical Engineering Technology Co.Ltd Hefei230051China

The Coriolis force method is a recently developed and highly regarded direct measurement technique that enables high-precision measurement of bulk *** operational parameters and variations thereof directly influence the measurement accuracy of the *** this study,a measurement correction coefficient is introduced to improve the calculation method for mass flow rate of the *** DEM is employed to simulate the motion of particle groups within the Coriolis force scale under different parameters,and the effects of various structural and operational parameters on the measurement results are *** research findings indicate that a lower rotational speed leads to more stable instantaneous measurement results,although the measurement error is relatively *** the rotational speed exceeds 300 rpm,the measurement error remains within 15%.For materials with a radius of 1–2 mm,the variation range of precision error is approximately 0.4%.Among the structural parameters,the radius of the measurement wheel has the most significant impact on the measurement results,wherein a larger measurement wheel radius corresponds to a smaller measurement *** horizontal angle of the blades follows as the next influential parameter,with a clockwise rotation and a horizontal angle of 30°resulting in a measurement error below 2%.

关键词： Parameter optimization Discrete element method Coriolis force scale Measurement error Numerical simulation

自动喷淋局部应用系统在古城镇文物建筑消防中的运用分析

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智能建筑与智慧城市 2017年第4期 41-43页

作者：汪皓岷西双版纳州公安消防支队

加强消防系统建设是减少和避免生命财产风险的良好保护措施,也是维持社会稳定和保障国家发展的关键步骤。自动喷水灭火系统以其高精度的运行机制和简单的操作模式越来越多地被广大火灾重点防范企业使用,作为局部应用系统以其精细简单的... 详细信息

加强消防系统建设是减少和避免生命财产风险的良好保护措施,也是维持社会稳定和保障国家发展的关键步骤。自动喷水灭火系统以其高精度的运行机制和简单的操作模式越来越多地被广大火灾重点防范企业使用,作为局部应用系统以其精细简单的模式和特点深受广大中小型企业的青睐。论文重点探讨了自动喷水灭火局部应用系统在建筑中的应用,尤其是在古建筑文物保护方面的使用,并针对应用中遇到的问题提出了一系列改进措施,对指导建筑单位的施工管理具有一定的借鉴意义。

关键词：自动喷水局部应用消防文物建筑

Reaction Mechanism of Actin ATP Hydrolysis Studied by QM/mm Calculations

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Chemical Research in Chinese Universities 2024年第5期40卷 849-855页

作者： wang Yiwen LIN Lirui XU Li-Yan LI En-Min DONG Geng Department of Biochemistry and Molecular Biology Shantou University Medical CollegeShantou515041P.R.China Department of Bioinformatics Shantou University Medical CollegeShantou515041P.R.China Medical Informatics Research Center Shantou University Medical CollegeShantou515041P.R.China Key Laboratory of Molecular Biology in High Cancer Incidence Coastal Area of Guangdong Higher Education Institutes Shantou University Medical CollegeShantou515041P.R.China Cancer Research Center Shantou University Medical CollegeShantou515041P.R.China Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology Shantou University Medical CollegeShantou515041P.R.China

Actin fibers are an important part of the cytoskeleton,providing vital support for the plasma *** function is driven by its ATPase(ATP:adenosine triphosphate)activity,i.e.,ATP+H_(2)O→ADP+*** seemingly simple reaction has attracted much attention because the hydrolysis of ATP provides energy to support life ***,the reaction mechanism of ATP hydrolysis in actin is not *** order to gain deep insights into the functions of actin,it is essential to elucidate the reaction mechanism of the actin ATP *** this paper,we have studied the reaction mechanism of the ATP hydrolysis in actin by the combined quantum mechanical and molecular mechanics(QM/mm)*** results show that 1)bond cleavage of the Pγ—OS of ATP and bond formation between oxygen of the lytic water and Pγatoms take place simultaneously,and this is the rate-limiting step of the hydrolysis;2)the proton on the lytic water transfers to the phosphate to form H_(2)P_(γ)O_(4)−via one bridge *** energy barrier of the complete reaction is 17.6 kcal/mol(1 kcal=4.184 kJ),which is in high agreement with the experimental value.

关键词： Actin Adenosine triphosphate(ATP)hydrolysis Quantum mechanical and molecular mechanics(QM/mm) Reaction mechanism

Nitrogen‑Doped Magnetic‑Dielectric‑Carbon Aerogel for High‑Efficiency Electromagnetic Wave Absorption

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Nano-Micro Letters 2024年第1期16卷 313-327页

作者： Shijie wang Xue Zhang Shuyan Hao Jing Qiao Zhou wang Lili Wu Jiurong Liu Fenglong wang Key Laboratory for Liquid‑Solid Structural Evolution and Processing of Materials Ministry of Education Shandong UniversityJinan 250061People’s Republic of China School of Mechanical Engineering Shandong UniversityJinan 250061People’s Republic of China Shenzhen Research Institute of Shandong University Shenzhen 518057GuangdongPeople’s Republic of China

Carbonbased aerogels derived from biomass chitosan are encountering a flourishing moment in electromagnetic protection on account of lightweight,controllable fabrication and ***,developing a facile construction method of component design with carbon-based aerogels for high-efficiency electromagnetic wave absorption(EWA)materials with a broad effective absorption bandwidth(EAB)and strong absorption yet hits some ***,the nitrogen-doped magnetic-dielectric-carbon aerogel was obtained via ice template method followed by carbonization treatment,homogeneous and abundant nickel(Ni)and manganese oxide(MnO)particles in situ grew on the carbon *** to the optimization of impedance matching of dielectric/magnetic components to carbon aerogels,the nitrogen-doped magnetic-dielectric-carbon aerogel(Ni/MnO-CA)suggests a praiseworthy EWA performance,with an ultra-wide EAB of 7.36 GHz and a minimum reflection loss(RLmin)of−64.09 dB,while achieving a specific reflection loss of−253.32 dB mm−***,the aerogel reveals excellent radar stealth,infrared stealth,and thermal management ***,the high-performance,easy fabricated and multifunctional nickel/manganese oxide/carbon aerogels have broad application aspects for electromagnetic protection,electronic devices and aerospace.

关键词： Electromagnetic wave absorption Wide bandwidth Dielectric-magnetic synergy Multifunction

Development of EPDM composites reinforced by CNTs@SiO_(2)for thermal protection systems of aerospace propulsion:Significant improvement in oxidation and ablation resistance properties

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Chinese Journal of Aeronautics 2024年第2期37卷 471-481页

作者： Li wang Jiang LI Kang LI Yiwei wang Chenyang MA Science and Technology on Combustion Internal Flow and Thermal-Structure LaboratoryNorthwestern Polytechnical UniversityXi’an 710072China

Carbon Nanotubes(CNTs)reinforced Polymer-Matrix Composites(PMCs)is widely used as insulation materials in thermal protection system of aerospace ***,CNTs are prone to oxidation and have high thermal conductivities,which makes it difficult to improve the ablation resistance of insulation materials that contain ***_(2)was encapsulated onto the surface of CNTs(CNTs@SiO_(2)),which were then added to Ethylene Propylene Diene Monomer(EPDM)rubber to prepare the insulation *** analysis and ablation test were used to evaluate the resistance of the insulation materials to thermal oxidation and ***,scanning electron microscopy was performed to analyze their *** revealed that the addition of CNTs@SiO_(2)could visibly reduce the effects of hot corrosion and ablation on insulation *** C-CNTs@SiO_(2)-1 formulation had the best ablative ***,compared with the unencapsulated formulation(C-CNTs-10),the C-CNTs@SiO_(2)-1 formulation reduced the line ablation rate by 51%to 0.0130 mm/s after oxygen-acetylene ***,the ablation mechanism was investigated based on the effects of the CNTs@SiO_(2)additive on their ***,the improvement in ablation performance may be attributed to CNTs@SiO_(2)-induced decreases in thermal conductivity,improvement in the hot corrosion resistance in the char layer,and changes in the microstructure.

关键词： Polymer-Matrix Composites(PMCs) Carbon Nanotubes(CNTs) Thermal properties Ablation Oxidation

Exceptional mechanical performance and macroscale superlubricity enabled by core-shell-like MoS_(2)/B_(4)C film

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Science China(Technological Sciences) 2024年第7期67卷 2018-2030页

作者： REN SiMing GAO ZhenRong FAN Xin wang HaiXin wang LiPing Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

Molybdenum disulfide(MoS_(2)) films are widely deployed in industrial applications owing to their inherent interlayer slip characteristics, offering energy consumption savings and prolonged mechanical part performance. Nevertheless, their practical utility is limited by environmental constraints and the limitations of preparation techniques, which hinder the attainment of robust superlubricity(friction coefficient mm^(3)N-1m^(-1)) under high contact stress in a mild vacuum environment. This noteworthy outcome is primarily attributable to the self-segmentation of the macroscale contact interface during the friction process, involving:(1) a large amount of wear debris is embedded into the wear track to create extensive micro-sized asperities;(2) a nanolayer of amorphous carbon enriched with oxide nanoparticles is formed on the uppermost part of these asperities;(3) numerous incommensurate nanocontacts comprising nanoparticles and highly oriented MoS_(2)nanosheets are established, culminating in the achievement of robust superlubricity. Our pioneering design, coupled with the elucidation of the underlying superlubricity mechanism, holds significant promise for advancing the development of robust and high-performance lubricants.

关键词： MoS_(2)/B_(4)C nanocomposites core-shell-like structure H/E ratio high-temperature friction macroscale superlubricity