检索结果-南通市图书馆

MULTI-MODE OF VORTEX-INDUCED VIBRATION OF A FLEXIBLE CIRCULAR CYLINDER

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 2011年第4期23卷 483-490页

作者： xie fang-fang DENG Jian ZHENG Yao School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China

The vortex-induced vibration of a flexible circular cylinder is investigated at a constant Reynolds number of 1000. The finite-volume method on moving meshes is applied for the fluid flow, and the Euler-Bernoulli beam theory is used to model the dynamic response of a flexible cylinder. The relationship between the reduced velocity and the amplitude response agrees well with the experimental results. Moreover, five different vibrating modes appear in the simulation. From the comparisons of their vortex structures, the strength of the wake flow is related to the exciting vibrating mode and different vortex patterns arise for different vibrating modes. Only 2P pattern appears in the first vibrating mode while 2S-2P patterns occur in the other vibrating modes if monitoring at different sections along the length of the cylinder. The vibration of the flexible cylinder can also greatly alter the three-dimensionality in the wake, which needs further studies in our future work, especially in the transition region for the Reynolds number from 170 to 300.

关键词： multi-mode Vortex-Induced Vibration (VIV) three-dimensional instability flexible cylinders Euler-Bemoulli beam

Controlled Self-assembly of Thermo-responsive Amphiphilic H-shaped Polymer for Adjustable Drug Release

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2018年第3期36卷 406-416页

作者： Yang Bai fang-Yuan xie Wei Tian College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi'an 710021China Ministry of Education Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Macromolecular Science and Technology School of ScienceNorthwestern Polytechnical UniversityXi’an 710072China Department of Pharmacy Eastern Hepatobiliary Surgery HospitalThe Second Military Medical UniversityShanghai 200438 China

Despite the fact that some progress has been made in the self-assembly of H-shaped polymers, the corresponding self-assemblies that respond to external stimulus and are further utilized to adjust the release of drugs are still deficient. The stimuli-responsive segments with amphiphilic H-shaped structure are generally expected to enhance the controllability of self-assembly process. The synthesis and self-assembly behavior of thermo-responsive amphiphilic H-shaped polymers with poly（ethylene glycol）（PEG）, polytetrahydrofuran （PTHF） and poly（N-isopropyl acrylamide）（PNIPAM） as building blocks are reported in this paper. The inner architecture structure and size of complex micelles formed by H-shaped self-assemblies were effectively adjusted when the solution temperature was increased above the lower critical solution temperature of PNIPAM segments. Furthermore, it was found that the architecture of self-assemblies underwent a transition from the complex micelles based on primary micelles with hybrid PEG/PNIPAM shells to large complex micelles based on primary micelles with hybrid PTHF/PNIPAM cores and PEG shells during the thermal-induced self-assembly process. The adjustable release rate ofdoxorubicin （DOX） from the DOX-loaded complex micelles and basic cell experiments further proved the feasibility of these self-assemblies as the thermal-responsive drug delivery system.

关键词： H-shaped polymer Thermo-responsive polymer Amphiphilic polymer Self-assembly Drug release

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2025年第1期17卷 13-21页

作者： Xian-Rong Wu Xiao-Hong He Yong-fang xie School of Life Health Information Science and Engineering Chongqing Post and Communications UniversityChongqing 400065China

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various *** recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus *** dysbiosis may promote the formation and recurrence of *** microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these *** the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut *** microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

关键词： Recurrent colorectal polyps Gut microbiota dysbiosis Klebsiella Probiotics Intestinal inflammation Microbial intervention strategy

Thickness-Dependent Microstructure and its Effect on Anisotropic Mechanical Properties of Duplex Stainless Steel 2205 Multi-pass Welded Joints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2023年第11期36卷 1883-1892页

作者： Zhilong Dong Xue-fang xie Jingwen Li Yu Wan State Key Laboratory of Heavy Oil Processing College of New EnergyChina University of Petroleum(East China)Qingdao266580China China National Offshore Oil Corporation Petrochemical Engineering Company Limited Jinan250000China

In this study,the thickness-dependent microstructural characteristics of duplex stainless steel 2205 multi-pass welded joints were first investigated by the combination of optical microscope and electron back-scattered diffraction ***,a series of tensile tests of miniature samples cut from different passes and directions were performed to analyze the thickness-dependent and anisotropic mechanical *** results demonstrate that the microstructure changed with the welded passes,i.e.,a large number of grain boundary austenite,Widmanstätten austenite and a small number of tiny intragranular austenite existed at the surface passes,while a mass of intragranular austenite were found at the middle ***,the Kurdjumov–Sachs orientation relationship was widespread at the welded *** addition,the yield and tensile strengths of the middle passes were greater than that of the surface passes due to the grain-boundary strengthening by tiny intragranular ***,due to the existence of Kurdjumov–Sachs orientation relationship,the longitudinal yield and tensile strength were greater than transverse values,particularly for the middle passes.

关键词： Duplex stainless steel Multi-pass welded joints Thickness-dependent microstructure Anisotropic mechanical properties

Unsteady simulation for a high-speed train entering a tunnel

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 Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 957-963页

作者： Xin-hua LI Jian DENG Da-wei CHEN fang-fang xie Yao ZHENG School of Aeronautics and Astronautics Zhejiang University Hangzhou 310027 China National Engineering Laboratory for System Integration of High-Speed Train （South） CSR Qingdao Sifang Co. Ltd Qingdao 266111 China

In order to study the unsteady aerodynamics effects in railway tunnels,the 3D Reynolds average Navier-Stokes equations of a viscous compressible fluid are solved,and the two-equation k-ε model is used in the simulation of turbulence,while the dynamic grid technique is employed for moving *** focus on obtaining the changing tendencies of the aerodynamic force of the train and the aerodynamic pressures on the tunnel wall and train surface,and discovering the relationship between the velocity of the train and the intensity of the micro pressure wave at the tunnel *** is shown that the amplitudes of the pressure changes in the tunnel and on the train surface are both approximately proportional to the square of the train speed,so are the microwave and the drag of the train.

关键词： High-speed train Aerodynamics Railway tunnel Numerical analysis

An update on the role of intestinal cytochrome P450 enzymes in drug disposition

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2016年第5期6卷 374-383页

作者： fang xie Xinxin Ding Qing-Yu Zhang Bioimaging Glaxo Smith KlineKing of Prussia College of Nanoscale Science SUNY Polytechnic Institute Wadsworth Center New York State Department of Health

Oral administration is the most commonly used route for drug *** cytochrome P450(CYP)-mediated metabolism can eliminate a large proportion of some orally administered drugs before they reach systemic circulation,while leaving the passage of other drugs unimpeded.A better understanding of the ability of intestinal P450 enzymes to metabolize various clinical drugs in both humans and preclinical animal species,including the identification of the CYP enzymes expressed,their regulation,and the relative importance of intestinal metabolism compared to hepatic metabolism,is important for improving bioavailability of current drugs and new drugs in ***,we briefly review the expression of drug-metabolizing P450 enzymes in the small intestine of humans and several preclinical animal species,and provide an update of the various factors or events that regulate intestinal P450 expression,including a cross talk between the liver and the *** further compare various clinical and preclinical approaches for assessing the impact of intestinal drug metabolism on bioavailability,and discuss the utility of the intestinal epithelium–specific NADPH-cytochrome P450 reductasenull(IECN) mouse as a useful model for studying in vivo roles of intestinal P450 in the disposition of orally administered drugs.

关键词： Cytochrome P450 Intestine Bioavailability Drug disposition Drug metabolism

An experimental study on anisotropy of thermal conductivity in shale

在线全文

学校读者我要写书评

暂无评论

Energy Geoscience 2023年第4期4卷 71-80页

作者： fang xie Chuanqing Zhu Boning Tang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China

Thermal conductivity plays a crucial role in heat transfer and geothermal field distribution in the *** the anisotropy of thermal conductivity in shale and its influencing factors is significant for resource evaluation in shale oil and gas *** this study,the thermal conductivity of shales in the Songliao and Sichuan basins was measured by laser scanning *** relationship between thermal conductivity and mineral composition,burial depth and stratigraphy was analyzed to investigate the anisotropy of shale thermal conductivity and its influencing *** results show that the thermal conductivity of shale ranges from 1.000 to 2.500 W/(m·K)at different *** thermal conductivity of shale is positively correlated with the content of high thermal conductivity minerals such as quartz and increases with burial *** anisotropy index of shale thermal conductivity ranges from 0.96 to *** heat flows through multiple laminae,the interfacial thermal resistance and the influence of the medium cause a decrease in the shale thermal conductivity as the angle between the heat flow direction and the laminae *** insights obtained are of reference significance for the accurate modeling of the thermal properties of shale sequences and the study of the geothermal field in shale oil and gas areas.

关键词： Thermal conductivity Shale Anisotropy Songliao Basin Sichuan Basin

Complementary two-phase anode improving stability and conductivity for lithium storage performance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2023年第1期42卷 85-99页

作者： Xue-fang xie Guo-Zhao fang Ying-Zhu Hu Xin-Xin Cao Ting Zhu An-Qiang Pan School of Materials Science&Engineering Central South UniversityChangsha410083China

Metal chalcogenides with multiple lithium ions storage capability have received extensive attentions in recent years;however,their practical application is restricted by the structural instability and poor ***,a unique structure of N and S co-doped C/TiO_(2)nanofibers is reported to support SnS nanosheets for fast and ultra-stable lithium *** incorporation of TiO_(2)can notably suppress the excessive uncontrollable growth of SnS and improve the structural stability of the electrode *** effects of the ratios between Ti and Sn and the corresponding synthesis temperatures on the structure and electrochemical properties of the electrodes have been systematically *** interface charge transfer behavior of SnS and TiO_(2)composite heterostructure was clarified by density functional theory(DFT)*** electronic interaction SnS and TiO_(2)can effectively reduce the energy band gap and form a built-in electric field at the interface of the two *** is beneficial for the adsorption of lithium ion and consequently accelerate the reaction kinetics of the electrode *** the two phases are combined,the agglomeration of SnS is effectively suppressed,and the overall conductivity of the composite is greatly ***,the synergistic effect induced by SnS and TiO_(2)enables the good stability of the electrode in both lithium-ion half-cells and full *** work can provide new insights toward improving the performance of alloy-type anodes.

关键词： SnS TiO_(2) Structural stability Battery

Partial Cubes and Archimedean Tilings

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2018年第4期34卷 782-791页

作者： Yun-jing PAN Ming-fang xie Fu-ji ZHANG ChengYi College Jimei University Xiamen 361021 China Jiangxia University Fuzhou 350108 China School of Mathematical Sciences Xiamen University Xiamen 361005 China

Some physicists depicted the molecular structure SnCl_2 · 2（H_2O） by a piece of an Archimedean tiling（4.8.8） that is a partial cube. Inspired by this fact, we determine Archimedean tilings whose connected subgraphs are all partial cubes. Actually there are only four Archimedean tilings,（4.***.4.4）,（6.6.6）,（4.8.8） and（4.6.12）, which have this property. Furthermore, we obtain analytical expressions for Wiener numbers of some connected subgraphs of（4.8.8） and（4.6.12） tilings. In addition, we also discuss their asymptotic behaviors.

关键词： archimedean tiling wiener number partial cube average distance