检索结果-南通市图书馆

Key technologies and development trends of the soft abrasive flow finishing method

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(applied Physics & Engineering) 2023年第12期24卷 1043-1064页

作者： Yunfeng TAN Yesha NI Weixin XU Yuanshen XIE Lin LI Dapeng TAN Key lab of E&M Ministry of Education&Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China State Key laboratory of fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China Collaborative Innovation Center of High-end Laser Manufacturing Equipment Zhejiang Province&Ministry of EducationHangzhou 310014China

This paper reviews recent developments of the soft abrasive flow finishing(SAF)method in constraint *** multiphase fluid dynamics modeling,material removal mechanism,auxiliary strengthening finishing techniques,and observation of surface impact effects by abrasive particles and cavitation bubbles are presented in *** prospects and challenges are given for four aspects:thin-walled curved surfaces,biomedical functions,electronic information,and precise optical components.

关键词： Soft abrasive flow finishing(SAF) Dynamic modeling Material removal mechanism Processing optimization Strengthening finishing control technology

A salt-induced tackifying polymer for enhancing oil recovery in high salinity reservoirs: Synthesis, evaluation, and mechanism

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

GREEN ENERGY & ENVIRONMENT 2024年第11期9卷 1747-1758页

作者： Wu, Yining Li, Peihan Yan, Bin Li, Xiaohan Huang, Yongping Yuan, Juncong Feng, Xiang Dai, Caili China Univ Petr East China Dept Petr Engn Qingdao 266580 Peoples R China Sichuan Univ Coll Biomass Sci & Engn Dept Natl Engn Lab Clean Technol Leather Manufacture Chengdu 610065 Peoples R China Princeton Univ Dept Civil & Environm Engn Princeton NJ 08544 USA China Univ Petr East China Dept Chem Engn Qingdao 266580 Peoples R China

Polymer flooding is an effective method widely applied for enhancing oil recovery (EOR) by reducing the mobility ratio between the injected water and crude oil. However, traditional polymers encounter challenges in high salinity reservoirs due to their salt sensitivity. To overcome this challenge, we synthesized a zwitterion polymer (PAMNS) with salt-induced tackifying property through copolymerization of acrylamide and a zwitterion monomer, methylacrylamide propyl-N, N-dimethylbutylsulfonate (NS). NS monomer is obtained from the reaction between 1,4-butanesultone and dimethylamino propyl methylacrylamide. In this study, the rheological properties, salt responsiveness, and EOR efficiency of PAMNS were evaluated. Results demonstrate that PAMNS exhibits desirable salt-induced tackifying characteristics, with viscosity increasing up to 2.4 times as the NaCl concentration reaches a salinity of 30 x 10(4) mg L-1. Furthermore, high valence ions possess a much stronger effect on enhancing viscosity, manifested as Mg2+ > Ca2+ > Na+. Molecular dynamics simulations (MD) and fluid dynamics experiment results demonstrate that PAMNS molecules exhibit a more stretched state and enhanced intermolecular associations in high-salinity environments. It is because of the salt-induced tackifying, PAMNS demonstrates superior performance in polymer flooding experiments under salinity ranges from 5 x 10(4) mg L-1 to 20 x 10(4) mg L-1, leading to 10.38-19.83% higher EOR than traditional polymers. (c) 2023 Institute of Process Engineering, Chinese Academy of Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).

关键词： High salinity reservoirs Salt-induced tackifying polymer Anti-polyelectrolyte behavior Enhanced oil recovery ZWITTERIONIC POLYMER BRUSHES SURFACE WATER BEHAVIOR

Impacts of the Leading Modes of Tropical Indian Ocean Sea Surface Temperature Anomaly on Sub-Seasonal Evolution of the Circulation and Rainfall over East Asia during Boreal Spring and Summer

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 Meteorological Research 2017年第1期31卷 171-186页

作者： Senfeng LIU Anmin DUAN State Key laboratory of Numerical Modelling for Atmospheric Sciences and Geophysical fluid dynamics Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology

The two leading modes of the interannual variability of the tropical Indian Ocean （TIO） sea surface temperature （SST） anomaly are the Indian Ocean basin mode （IOBM） and the Indian Ocean dipole mode （IODM） from March to August. In this paper, the relationship between the TIO SST anomaly and the sub-seasonal evolution of the circula- tion and rainfall over East Asia during boreal spring and summer is investigated by using correlation analysis and composite analysis based on multi-source observation data from 1979 to 2013, together with numerical simulations from an atmospheric general circulation model. The results indicate that the impacts of the IOBM on the circulation and rainfall over East Asia vary remarkably from spring to summer. The anomalous anticyclone over the tropical Northwest Pacific induced by the warm IOBM is closely linked with the Pacific-Japan or East Asia-Pacific telecon- nection pattern, which persists from March to August. In the upper troposphere over East Asia, the warm phase of the IOBM generates a significant anticyclonic response from March to May. In June and July, however, the circulation response is characterized by enhanced subtropical westerly flow. A distinct anomalous cyclone is found in August. Overall, the IOBM can exert significant influence on the western North Pacific subtropical high, the South Asian high, and the East Asian jet, which collectively modulate the precipitation anomaly over East Asia. In contrast, the ef- fects of the IODM on the climate anomaly over East Asia are relatively weak in boreal spring and summer. There- fore, studying the impacts of the TIO SST anomaly on the climate anomaly in East Asia should take full account of the different sub-seasonal response during boreal spring and summer.

关键词： East Asia sub-seasonal evolution Indian Ocean basin mode Indian Ocean dipole mode

Numerical method for simulating rarefaction shocks in the approximation of phase-flip hydrodynamics

在线全文

学校读者我要写书评

暂无评论

applied Mathematics and Mechanics(English Edition) 2021年第6期42卷 871-884页

作者： M.M.BASKO Keldysh Institute of applied Mathematics Russian Academy of SciencesMiusskaya Square 4Moscow 125047Russia

A finite-difference algorithm is proposed for numerical modeling of hydrodynamic flows with rarefaction shocks, in which the fluid undergoes a jump-like liquid-gas phase transition. This new type of flow discontinuity, unexplored so far in computational fluid dynamics, arises in the approximation of phase-flip(PF) hydrodynamics, where a highly dynamic fluid is allowed to reach the innermost limit of metastability at the spinodal, upon which an instantaneous relaxation to the full phase equilibrium(EQ) is assumed. A new element in the proposed method is artificial kinetics of the phase transition, represented by an artificial relaxation term in the energy equation for a "hidden"component of the internal energy, temporarily withdrawn from the fluid at the moment of the PF transition. When combined with an appropriate variant of artificial viscosity in the Lagrangian framework, the latter ensures convergence to exact discontinuous solutions, which is demonstrated with several test cases.

关键词： fluid dynamics with phase transitions two-phase flow rarefaction shock Lagrangian scheme artificial viscosity artificial kinetics

Counter-current three-phase fluidization in a turbulent contact absorber： A CFD simulation

在线全文

学校读者我要写书评

暂无评论

Particuology 2017年第6期15卷 51-67页

作者： Syed Shah Jehan Gillani Atta Ullah Muhammad Zaman Imran Rafique Chugtai Mansoor Hameed Inayat Department of Chemical Engineering Pakistan Institute of Engineering and Applied Sciences (PIEAS) 45650 Islamabad. Pakistan

A computational fluid dynamics study of three-phase counter-current fluidization occurring in a turbu- lent contact absorber was performed. A two-dimensional, transient Eulerian multi-fluid model was used, in which the dispersed solid phase was modeled employing a kinetic theory of granular flow. The grid independence of the model, the effect of wall boundary conditions, the choice of granular temperature model, the effects of order of discretization scheme and drag models were studied for a base case setting, The results of simulations were validated against experimental results obtained from the literature. Once the model settings were finalized, simulations were performed for different gas and liquid velocities to predict the hydrodynamics of the absorber. Computed bed expansion and pressure drop were compared with experimental data. Good agreement between the two was found for low velocities of gas and liquid.

关键词： multiphase Counter-current Computational fluid dynamics (CFD) fluidization Turbulent contact absorber

The Warm Arctic-Cold Eurasia Pattern and Its Key Region in Winter in CMIP6 Model Simulations

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 2023年第12期40卷 2138-2153,I0002-I0006页

作者： Liang ZHAO Yunwen LIU Yihui DING Qingquan LI Wei DONG Xinyong SHEN Wei CHENG Haoxin YAO Ziniu XIAO State Key laboratory of Numerical Modeling for Atmosphere Sciences and Geophysical fluid dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Neijiang Meteorological Bureau Neijiang 641000China China Meteorological Administration National Climate CenterBeijing 100081China Key laboratory of Geoscience Big Data and Deep Resource of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China Southern Marine Science and Engineering Guangdong laboratory(Zhuhai) Zhuhai 519082China Beijing Institute of the applied Meteorology Beijing 100029China

An enhanced Warm Arctic-Cold Eurasia(WACE)pattern has been a notable feature in recent winters of the Northern ***,divergent results between model and observational studies of the WACE still *** study evaluates the performance of 39 climate models participating in the Coupled Model Intercomparison Project phase 6(CMIP6)in simulating the WACE pattern in winter of 1980-2014 and explores the key factors causing the differences in the simulation capability among the *** results show that the multimodel ensemble(MME)can better simulate the spatial distribution of the WACE pattern than most single *** that can/cannot simulate both the climatology and the standard deviation of the Eurasian winter surface air temperature well,especially the latter,usually can/cannot simulate the WACE pattern *** mainly results from the different abilities of the models to simulate the range and intensity of the warm anomaly in the Barents Sea-Kara seas(BKS)*** analysis shows that a good performance of the models in the BKS area is usually related to their ability to simulate location and persistence of Ural blocking(UB),which can transport heat to the BKS region,causing the warm Arctic,and strengthen the westerly trough downstream,cooling central ***,simulation of UB is key and significantly affects the model’s performance in simulating the WACE.

关键词： warm Arctic-cold Eurasia pattern Arctic amplification CMIP6 simulation evaluation extreme climate blocking highs

Understanding the Recovery of the Intervertebral Disc:A Comprehensive Review of In Vivo and In Vitro Studies

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第4期21卷 1919-1948页

作者： Faten Feki Fahmi Zaïri Abderrahman Tamoud Melissa Moulart Rym Taktak Nader Haddar Fahed Zaïri Sfax University ENISMaterials Engineering and Environment Laboratory3038SfaxTunisia University of Lille IMT Nord EuropeJUNIAUniversity of ArtoisULR 4515-LGCgELaboratoire de Génie Civil et geo-Environnement59000LilleFrance PrediTwins lab 59000LilleFrance Japet Medical Device 59000LilleFrance Sfax University ENISLaboratory of Advanced Materials3038SfaxTunisia Ramsay Générale de Santé Hôpital PrivéLe Bois59000LilleFrance

Within the consistent daily rhythm of human life,intervertebral discs endure a variety of complex loads beyond the influences of gravity and muscle forces,leading to significant morphological changes(in terms of volume,area,and height)as well as biomechanical alterations,including an increase in disc stiffness and a decrease in intradiscal ***,the discs demonstrate an ability to regain their original morphological and biomechanical characteristics after a period of nocturnal *** preservation of normal disc function is critically dependent on this recovery phase,which serves to forestall premature disc *** phenomenon of disc recovery has been extensively documented through numerous in vivo studies employing advanced clinical techniques such as Magnetic Resonance Imaging(MRI),stadiometry,and intradiscal pressure ***,the findings from in vitro studies present a more complex picture,with reports varying between full recovery and only partial recuperation of the disc ***,research focusing on degenerated discs in vitro has shed light on the quantifiable impact of degeneration on the disc ability to *** dynamics within the disc are considered a primary factor in recovery,yet the disc intricate multiscale structure and its viscoelastic properties also play key *** elements interact in complex ways to influence the recovery mechanism,particularly in relation to the overall health of the *** objective of this review is to collate,analyze,and critically evaluate the existing body of in vivo and in vitro research on this topic,providing a comprehensive understanding of disc recovery *** understanding offers a blueprint for future advancements in medical treatments and bionic engineering solutions designed to mimic,support,and enhance the natural recovery processes of intervertebral discs.

关键词： Intervertebral disc Recovery In vivo vs.in vitro studies Degeneration Viscoelastic effects fluid dynamics

Discrete and continuum modeling of dislocations in crystal

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Discrete and continuum modeling of dislocations in crystal

白云鄂博矿床碳酸岩墙/脉和赋矿白云岩中流体包裹体研究

中国计算力学大会2014暨第三届钱令希计算力学奖颁奖大会

作者： Zhanli Liu Yinan Cui Liyuan Wang Zhuo Zhuang applied Mechanics lab. School of AerospaceTsinghua University

The discrete dislocation plasticity in crystals is investigated by Discrete Dislocation dynamics(DDD)and micro-scale continuum crystal plasticity theory,respectively,in this *** the DDD modeling,a unified computational model which directly combines 3D DDD and Finite Element Method(FEM)is developed to investigate the discrete dislocation plasticity in a finite *** this model,1)an initial internal stress field is introduced to represent the preexisting stationary dislocations in the crystal;2)the external boundary condition is handled by finite element method spontaneously;3)the constitutive relationship is based on the finite deformation theory of crystal plasticity,but the discrete plastic strains induced by the slip of dislocations are calculated by dislocation dynamics methodology instead of phenomenological constitutive equations used in conventional crystal *** processes,such as loop dislocation evolution,dislocation junction formation *** simulated to verify the reliability of this computational *** challenges in the current DDD modeling are also discussed,such as it is difficult to deal with dislocations in heterogeneous materials and to consider the evolution of more than one types of defects,*** solve these problems,it is useful to describe the defects in a continuum manner.A new method for modeling dislocations continuously is developed based on the continuum crystal plasticity *** with conventional crystal plasticity theory,the‘plastic slip’associated with each dislocation sweep is described by a continuous smooth field *** evolution of plastic slip field is described through Ginzburg-Laudau equation,similar to that used in phase field method(PFM).The advantage is the elastic interaction between dislocations as well as the interaction between dislocations and internal/external interfaces are automatically taken into account within a unified continuum mechanics *** examples are

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

岩石学报 2007年第1期23卷 161-168页

作者：秦朝建裘愉卓周国富王中刚张台荣肖国望 State Key lab of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002 State Key lab of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002 Key Lab of Dynamics of MineralizationGuangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640 Bayan Obo Iron Mine Baotou Steel-Iron GroupBaotou 014080

fluid inclusion study has been carried out for the carbonatite dykes/veins and the ore-hosted dolostone of the Bayan Obo superlarge REE-Fe-Nb deposit in order to provide the evidence and constraint for their *** on the detailed geological observation and mineralogical investigation,the heating and cooling stage and laser Raman spectroscopy were mainly used for the laboratory work of this *** results have been obtained:(1)The discovery of melt and melt-fluid inclusions from carbonatite dykes/veins in the Dulahara and Jianshan Mountains,combined with the fine-grained(aplitic)texture of rocks,as well as the types and features of fluid inclusions such as CO_2 enrichment,higher homogenization temperature,provides a direct evidence for the magmatic origin of these dykes/veins.(2)The carbonatite dykes/veins distributed in two regions,nearby the axis of the Kuangou anticline and in the east to Bayan Obo town,mainly show coarse-grained *** melt inclusion was found,and the fluid inclusions possess features of less CO_2,lower homogenization temperature and higher *** are tentatively identified as veins formed by some carbonate-rich hydrothermal solution.(3)Bedding carbonate layers/lens within the hanging wall and foot wall of ore-hosted dolostone,previously recognized as of magmatic origin,mainly composed by *** existence of single phase pure aqueous inclusions with very low homogenization temperature indicates their sedimentary origin.(4)The ore-hosted dolostone possesses apparent bedding and laminated *** melt inclusion was found,but,both single phase pure aqueous inclusions and CO_2 bearing multi-phase fluid inclusions coexisted in *** the direction towards ore-bodies,the homogenization temperature and CO_2 contents of fluid inclusion show an increasing *** indicates the sedimentary origin of dolostone superimposed by late fluid metasomatism.

关键词：白云鄂博矿床碳酸岩墙/脉赋矿白云岩流体包裹体