检索结果-南通市图书馆

science China(Technological sciences) 2009年第1期52卷 72-78页

作者： wang bo1, wang rongxiu2.& wu yong1 1 school of mathematic science,{2., chongqing 400050, China 2.Department of Computer science and Information Engineering, chongqing technology and Business University, chongqing 400067, China school of mathematic{2. Chongqing Institute of Technology Chongqing 400050 China Department of Computer science and Information Engineering Chongqing Technology and Business University Chongqing 400067 China

The elastic moduli of short-fiber-reinforced foams depend critically on the fiber content and fiber length, as well as on the fiber orientation distribution. Based on periodic tetrakaidecahedrons, the finite element models with short-fiber reinforcement were proposed in this paper to examine the effects of the fiber content and fiber length on Young's modulus. The fiber length distribution and fiber orientation distribution were also considered. The proposed models featured in a three-dimensional diorama with random short-fiber distribution within or on the surfaces of the walls and edges of the closed-cells of polypropylene (PP) foams. The fiber length/orientation distributions were modeled by Gaussian prob-ability density functions. Different fiber volume fractions, different lengths, and different distributions were investigated. The predicted Young's moduli of the PP foams with short-glass-fiber or short-carbon-fiber reinforcement were compared with other theoretic and experimental results, and the agreement was found to be satisfactory. The proposed finite element models were proved to be acceptable to predict the Young's moduli of the grafted closed-cell PP foams with short-fiber reinforcement.

关键词： short-fiber reinforcement Young’s modulus finite element Gaussian distribution

维普期刊数据库

A solution using only electromagnetic coils for relative pose control in satellite docking

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第3期37卷 258-281页

作者： Guangzheng RUAN Lijian wu bo {2. Yaobing {2. Runqi HAN College of Electrical Engineering Zhejiang UniversityHangzhou 310012China Beijing institute of Spacecraft System Engineering Beijing 100094China

This paper proposes an electromagnetic coil topology and its control strategy,which can be incorporated into the electromagnetic docking device to achieve relative pose control in satellite *** target satellite has a main coil;the chaser satellite possesses a main coil of the same size accompanied by six and four evenly arranged secondary coils inside and outside the main coil,*** coil on the target satellite is DC energized,while the currents in the coils of the chaser satellite are *** remove the coupling between the pitch/yaw torque and translational force,the internal and external secondary coils of the chaser satellite interact with the main coil of the target satellite to perform the control of relative pitch/yaw and relative translation,respectively,so relative pose control can be *** torque and force vectors exerted by the secondary coils of the chaser satellite are synthesized onto the pitch and yaw axes of the body *** to their spatial composition relationship,the formulas are proposed,which obtain the magnetic moment vectors of the coils from the set torques and *** controllers regulating pitch/yaw,translation,and distance utilize a three-loop cascaded structure that consists of an outer position loop,a middle velocity loop and an inner current *** control strategy is verified by dynamics simulation.

关键词： Electromagnetic docking 6 degree of freedom Relative pose control Coil array Far field model Motion decoupling

维普期刊数据库

Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

在线全文

学校读者我要写书评

暂无评论

Petroleum science 2024年第4期21卷 2839-2848页

作者： yong Hu Xi Lu Hai-bo {2. Ji-Chao Fang Yi-Ning wu Jian Fang Sun SINOPEC Petroleum Exploration and Production Research institute Shandong Key Laboratory of Oilfield Chemistry School of Petroleum Engineering China University of Petroleum (East China)

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ωasp) is 0-2. wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase of ω*** ωaspincreases from 0 to 2. wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** the ωaspincreases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

A novel alternative for pyrogen detection based on a transgenic cell line

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第3期9卷 1221-1229页

作者： Qing He Chuan-Fei Yu Gang wu Kai-Qin wang {2.-bo Ni Xiao Guo Zhi-Hao Fu Lan wang De-Jiang Tan Hua Gao Can wang Gang Chen Xu-Hong Chen bo Chen Jun-Zhi wang National institutes for Food and Drug Control BeijingChina school of Life science and Biopharmaceutics Shenyang Pharmaceutical UniversityShenyangChina Shanghai institute for Food and Drug Control ShanghaiChina KeyMed Biosciences Inc. ChengduChina

Pyrogen,often as a contaminant,is a key indicator affecting the safety of almost all parenteral drugs(including biologicals,chemicals,traditional Chinese medicines and medical devices).It has become a goal to completely replace the in vivo rabbit pyrogen test by using the in vitro pyrogen test based on the promoted‘reduction,replacement and refinement’principle,which has been highly considered by regulatory agencies from different *** used NF-κB,a central signalling molecule mediating inflammatory responses,as a pyrogenic marker and the monocyte line THP-1 transfected with a luciferase reporter gene regulated by NF-κB as an in vitro model to detect pyrogens by measuring the intensity of a fluorescence ***,we show that this test can quantitatively and sensitively detect endotoxin(lipopolysaccharide from different strains)and nonendotoxin(lipoteichoic acid,zymosan,peptidoglycan,lectin and glucan),has good stability in terms of NF-κB activity and cell phenotypes at 39 cell passages and can be applied to detect pyrogens in biologicals(group A&C meningococcal polysaccharide vaccine;basiliximab;rabies vaccine(Vero cells)for human use,freeze-dried;Japanese encephalitis vaccine(Vero cells),inactivated;insulin aspart injection;human albumin;recombinant human erythropoietin injection(CHO Cell)).The within-laboratory reproducibility of the test in three independent laboratories was 85%,80%and 80%and the interlaboratory reproducibility among laboratories was 83.3%,95.6%and 86.7%.The sensitivity(true positive rate)and specificity(true negative rate)of the test were 89.9%and 90.9%,*** summary,the test provides a novel alternative for pyrogen detection.

关键词： pyrogen rabbit replace

Jetting of a near-wall cavitation bubble induced by another tandem bubble

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2024年第3期36卷 444-456页

作者： Hui Han Jing-zhu wang Jian-lin Huang Peng-bo Bai {2.-gang Chen Yi-wei wang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China school of Engineering science University of Chinese Academy of SciencesBeijing100049China Guangdong Aerospace Research Academy Guangzhou511458China school of Future technology University of Chinese Academy of SciencesBeijing100049China Jianghuai Advance technology Center Hefei230088China

Double bubbles near a rigid wall surface collapse to produce a significant jet impact,with potential applications in surface cleaning and ultrasonic ***,the dynamic behaviors of near-wall bubbles remain *** this study,we investigate the jetting of a near-wall bubble induced by another tandem *** define two dimensionless standoff distances,γ_(1),γ_(2.,to represent the distances from the center of the near-wall bubble to the rigid wall and the center of controlling bubble to the center of the near-wall bubble,*** observations reveal three distinct jetting regimes for the near-wall bubble:transferred jetting,double jetting,and directed *** further investigate the jetting mechanism,numerical simulations are conducted using the compressibleInterFoam solver in the open-source framework of OpenFOAM.A detailed analysis shows that the transferred jet flow is caused by the pinch-off resulting from the axial contraction velocity at the lower end of the near-wall bubble being greater than the vertical contraction velocity,leading to a maximum jet velocity of 682.58 m/*** the case of double jetting,intense stretching between the controlling bubble and the wall leads to a pinch-off and a double jetting with a maximum velocity of 1096.2. m/*** directed jet flow is caused by the downward movement of the high-pressure region generated by the premature collapse of the controlling bubble,with the maximum jet velocity reaching 444.62.m/s.

关键词： Jetting of near-wall bubble controlling bubble impact velocity

Protein crystallization with DNA templates

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第3期86卷 262-268页

作者： bo Zhang Jia Yu Zhe Pu Wenhui Guo Ruoqi Yang Yu Wen Zhijiang Rong Hui wang Xiaoli {2. bo wang Hongyan Sun school of Environment and Resources Taiyuan University of Science and TechnologyTaiyuan030024China school of Chemical Engineering and technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of DNA,single-stranded DNA with 10,2.,40 bases and double-stranded DNA with 10,2.,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates ***-stranded DNA led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA *** number and crystallization rate was enhanced with addition of long double-stranded DNA *** the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization

Recent advances and applications of single atom catalysts based electrochemical sensors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第4期17卷 2994-3013页

作者： Mingyue wang Mingfu Ye Jieyue wang {2. Xu Zhendong wang Xinyue Tong Xinya Han Kui Zhang Wenhai wang Konglin wu Xianwen Wei institute of Clean Energy and Advanced Nanocatalysis(iClean) School of Chemistry and Chemical EngineeringAnhui University of TechnologyMaanshan 243002China school of Materials science and Engineering Anhui University of TechnologyMaanshan 243002China Anhui International Research Center of Energy materials green manufacturing and biotechnology School of Chemistry and Chemical EngineeringAnhui University of TechnologyMaanshan 243002China Carbon Cycle and Emission Control Research Center Low-Carbon Research InstituteAnhui University of TechnologyMaanshan 243002China

Single atom catalysts(SACs)have attracted considerable attention due to their unique structures and excellent catalytic performance,especially in the area of catalysis science and energy conversion and *** recent years,SACs have emerged as a new type of sensing material for constructing electrochemical sensors(ECSs),presenting excellent sensitivity,selectivity,and ***,we review the recent advances of SACs in electrochemical sensing and discuss the status quo of current SAC-based ***,the fundamentals of SAC-based ECSs are outlined,including the involved central metal atoms and various supports of SACs in this field,the detection mechanisms,and improving strategies of SAC-based ***,the important applications of SAC-based ECSs are listed and classified,covering the detection of reactive oxygen and nitrogen species,environmental pollutants,disease biomarkers,and ***,based on abundant reported cases,the current conundrums of SAC-based ECSs are summarized,and the prediction of their future developing trends is also put forward.

关键词： single atom catalysts(SACs) electrochemical sensors(ECSs) reactive oxygen and nitrogen species environmental pollutants disease biomarkers pharmaceuticals

Theoretical and experimental research on static stiffness,performance,and lift-off characteristics of multi-layer gas foil thrust bearings

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2024年第11期12卷 2458-2479页

作者： Yang HU Pengjing DING Fangling wu Xiaojing wang {2. LIANG yonggang MENG school of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200072China Aviation Key Laboratory of science and {2. on Aero Electromechanical System Integration Nanjing Engineering Institute of Aircraft SystemsNanjing 211106China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

In this study,a new comprehensive fully coupled elastic–hydrodynamic model is developed for a multi-layer gas foil thrust bearing(GFTB).The interaction effects among the top foil,back board,middle foil,and bottom foil,as well as the Coulomb friction effect,are *** stiffness and static characteristics obtained by the experimental and theoretical approaches are in good agreement,which verifies the accuracy of the *** contribution of each foil layer to the overall stiffness and the load-carrying mechanism are *** effects of the load,preload,and rotational speed on the static performance are investigated ***,start–stop tests are performed to achieve the lift-off speed,start-up torque,and shut-down torque under various operating conditions.

关键词： multi-layer gas foil thrust bearing(GFTB) load carrying mechanism static performance

Tjong:A transformer‐based Mahjong AI via hierarchical decision‐making and fan backward

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence technology 2024年第4期9卷 982-995页

作者： Xiali Li bo Liu Zhi Wei Zhaoqi wang Licheng {2. school of Information and Engineering Minzu University of ChinaBeijingChina Key Laboratory of Ethnic Language Intelligent Analysis and Security Governance of MOE Minzu University of ChinaBeijingChina Department of Computer science New Jersey Institute of TechnologyNewarkNew JerseyUSA

Mahjong,a complex game with hidden information and sparse rewards,poses significant *** Mahjong AIs require substantial hardware resources and extensive datasets to enhance AI *** authors propose a transformer‐based Mahjong AI(Tjong)via hierarchical decision‐*** utilising self‐attention mechanisms,Tjong effectively captures tile patterns and game dynamics,and it decouples the decision pro-cess into two distinct stages:action decision and tile *** design reduces de-cision complexity ***,a fan backward technique is proposed to address the sparse rewards by allocating reversed rewards for actions based on winning *** consists of 15M parameters and is trained using approximately 0.5 M data over 7 days of supervised learning on a single server with 2.*** action decision achieved an accuracy of 94.63%,while the claim decision attained 98.55%and the discard decision reached 81.51%.In a tournament format,Tjong outperformed AIs(CNN,MLP,RNN,ResNet,VIT),achieving scores up to 2.0%higher than its ***-more,after 3 days of reinforcement learning training,it ranked within the top 1%on the leaderboard on the botzone platform.

关键词： decision making deep learning deep neural networks

Refining the Factors Affecting N_(2.O Emissions from Upland Soils with and without Nitrogen Fertilizer Application at a Global Scale

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric sciences 2024年第9期41卷 1804-1820页

作者： Wenqian JIANG Siqi LI yong LI Meihui wang {2. wang Ji LIU Jianlin SHEN Xunhua ZHENG State Key Laboratory of Atmospheric boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory for Agro-ecological Processes in Subtropical Regions Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China Changsha Research Station for Agricultural&Environmental Monitoring Chinese Academy of SciencesChangsha 410125China University of Chinese Academy of sciences Beijing 100049China State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environment SciencesShanghai 200233China institute of Carbon Neutrality Qilu ZhongkeJinan 251699China Hubei Province Key Laboratory for Geographical Process Analysis and Simulation Central China Normal UniversityWuhan 430079China Department of Ecohydrology Leibniz Institute of Freshwater Ecology and Inland FisheriesBerlin 12587Germany Key laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning 530001China Golden Mantis school of Architecture Soochow UniversitySuzhou 215123China

Nitrous oxide(N_(2.O)is a long-lived greenhouse gas that mainly originates from agricultural *** and more studies have explored the sources,influencing factors and effective mitigation measures of N_(2.O in recent ***,the hierarchy of factors influencing N_(2.O emissions from agricultural soils at the global scale remains *** this study,we carry out correlation and structural equation modeling analysis on a global N_(2.O emission dataset to explore the hierarchy of influencing factors affecting N_(2.O emissions from the nitrogen(N)and non-N fertilized upland farming systems,in terms of climatic factors,soil properties,and agricultural *** results show that the average N_(2.O emission intensity in the N fertilized soils(17.83 g N ha^(-1)d^(-1))was significantly greater than that in the non-N fertilized soils(5.34 g N ha^(−1) d^(−1))(p1).Climate factors and agricultural practices are the most important influencing factors on N_(2.O emission in non-N and N fertilized upland soils,*** different climatic zones,without fertilizer,the primary influence factors on soil N_(2.O emissions are soil physical properties in subtropical monsoon zone,whereas climatic factors are key in the temperate *** fertilizer,the primary influence factors for subtropical monsoon and temperate continental zones are soil physical properties,while agricultural measures are the main factors in the temperate monsoon *** enhanced agricultural practices,such as reduced N fertilizer rate combined with the addition of nitrification and urease inhibitors can potentially mitigate N_(2.O emissions by more than 60%in upland farming systems.

关键词： N_(2.O emissions influencing factors nitrogen cycling upland farming systems

维普期刊数据库