检索结果-南通市图书馆

Communications in Theoretical Physics 2019年第10期71卷 1163-1171页

作者： Na Hao yong-jun jian School of Mathematical Science Inner Mongolia University

This paper investigates the magnetohydrodynamic(MHD) electroosmotic flow(EOF) of Newtonian fluid through a zeta potential modulated parallel plate microchannel with patterned hydrodynamic slippage. The driven mechanism of the flow originates from the Lorentz force generated by the interaction of externally imposed lateral electric field Ey and vertical magnetic field Bz and electric field force produced by an externally applied electric field Ex. It is assumed that the wall zeta potential and the slip length are periodic functions of axial coordinate x, an analytical solution of the stream function is achieved by utilizing the method of separation of variables and perturbation expansion. The pictures of streamlines are plotted and the vortex configurations produced in flow field due to patterned wall potential and hydrodynamic slippage are discussed. Based on the stream function, the velocity field and volume flow rate are obtained, which are greatly depend on some dimensionless parameters, such as slip length ls, electrokinetic widthλ, the amplitude δ of the patterned slip length, the amplitude m of the modulated zeta potential and Hartmann number Ha. The variations of velocity and volume flow rate with these dimensionless parameters are discussed in details. These theoretical results may provide some guidance effectively operating micropump in practical nanofluidic applications.

关键词： magnetohydrodynamic(MHD) flow electroosmotic flow(EOF) modulated hydrodynamic slippage patterned charged surface

Effect of patterned hydrodynamic slip on electromagnetohydrodynamic flow in parallel plate microchannel

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2020年第11期29卷 308-314页

作者： Chun-Hong Yang yong-jun jian School of Mathematical Science Inner Mongolia UniversityHohhot 010021China

A fully developed electromagnetohydrodynamic(EMHD) flow through a microchannel with patterned hydrodynamic slippage on the channel wall is studied. The flow is driven by the Lorentz force which originates from the interaction between an externally imposed lateral electric field and a perpendicular magnetic field. The governing equations for the velocity with patterned slip boundary conditions are solved analytically by perturbation techniques under the assumption of small Reynolds number Re. In addition, the numerical solutions for the velocity are obtained by using the finite-difference method, and they are found to be in good agreement with the analytical solutions within admissible parameter range. The effects of different parameters on the velocity and volume flow rate due to patterned hydrodynamic slippage are discussed in detail, including wave-number K, Hartmann number Ha, amplitude δ of the patterned slip length, and normalized electric field strength S. The results show that patterned slippage over microchannel walls can induce transverse flows, which will increase the mixing rates in microfluidic devices. In addition, we also find that precise flow control can be achieved by controlling the magnetic flux and the wave-number and also by well choosing the electric field intensity. Our analysis can be used for designing the efficient micro-fluidic mixers.

关键词： electromagnetohydrodynamic(EMHD)flow patterned slip wall

Instability of single-walled carbon nanotubes conveying Jeffrey fluid

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第4期30卷 328-332页

作者： Bei-Nan Jia yong-jun jian School of Mathematical Science Inner Mongolia UniversityHohhot 010021China

We report instability of the single-walled carbon nanotubes(SWCNT) filled with non-Newtonian Jeffrey *** objective is to get the influences of relaxation time and retardation time of the Jeffrey fluid on the vibration frequency and the decaying rate of the amplitude of carbon *** elastic Euler-Bernoulli beam model is used to describe vibrations and structural instability of the carbon nanotubes.A new vibration equation of an SWCNT conveying Jeffrey fluid is first derived by employing Euler-Bernoulli beam equation and Cauchy momentum equation taking constitutive relation of Jeffrey fluid into *** complex vibrating frequencies of the SWCNT are computed by solving a cubic eigenvalue problem based upon differential quadrature method(DQM).It is interesting to find from computational results that retardation time has significant influences on the vibration frequency and the decaying rate of the ***,the vibration frequency decreases and critical velocity increases with the retardation *** is to say,longer retardation time makes the SWCNT more stable.

关键词： single-walled carbon nanotubes Jeffrey fluid relaxation time retardation time

Transient electro-osmotic and pressure driven flows of two-layer fluids through a slit microchannel

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2013年第4期29卷 534-542页

作者： Jie Su yong-jun jian Long Chang Quan-Sheng Liu School of Mathematical Science Inner Mongolia University School of Mathematics and Statistics Inner Mongolia University of Finance and Economics

By method of the Laplace transform, this arti- cle presents semi-analytical solutions for transient electro- osmotic and pressure-driven flows （EOF/PDF） of two-layer fluids between microparallel plates. The linearized Poisson- Boltzmann equation and the Cauchy momentum equation have been solved in this article. At the interface, the Maxwell stress is included as the boundary condition. By numerical computations of the inverse Laplace transform, the effects of dielectric constant ratio e, density ratio p, pressure ratio p, viscosity ratioμ of layer II to layer I, interface zeta potential difference △ψ, interface charge density jump Q, the ratios of maximum electro-osmotic velocity to pressure velocity , and the normalized pressure gradient B on transient veloc- ity amplitude are *** find the velocity amplitude becomes large with the interface zeta potential difference and becomes small with the increase of the viscosity. The ve- locity will be large with the increases of dielectric constant ratio; the density ratio almost does not influence the EOF ve- locity. Larger interface charge density jump leads to a strong jump of velocity at the interface. Additionally, the effects of the thickness of fluid layers （hi and h2） and pressure gradient on the velocity are also investigated.

关键词： Hydromechanics ~ Micro-parallel plates ~ Elec-tric double layer (EDL) ~ Unsteady EOF/PDF ~ Two-layerNewtonian fluids

Pressure Oscillating Flow in Corrugated Parallel Channel

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2016年第12期65卷 694-700页

作者： Yu-Fei Wei Hai-jun Wang yong-jun jian Department of Physiology Hetao College Bayannur 015000 China Mathematical Science College Inner Mongolia Normal University Hohhot 010022 China School of Mathematical Sciences Inner Mongolia University Hohhot 010021 China

The approximate analytical solution of velocity is presented for incompressible and viscous fluid driven by the oscillation of the periodic pressure, between two slit parallel plates with corrugated walls by employing perturbation method. The corrugations of the two walls are described as periodic sinusoidal waves with small amplitude either in phase or half-period out of phase. Based on the analysis, we discuss the influence of the dimensionless parameters on velocity u±and mean velocity parameter φ±numerically, such as Reynolds number Re, nondimensional amplitude A of pressure gradient and wave number k.

关键词： corrugated walls perturbation method oscillating pressure

Synthesis and Crystal Structure of 5-N-i-Propyl-2-(2′-nitrobenzenesulfonyl)-glutamine

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2006年第6期22卷 760-762页

作者： XIAO yong-jun WANG jian-guo WANG Bao-lei LI Zheng-ming SONG Hai-bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

The title compound, 5 -N-i-propyl-2-（2＇ -nitrobenzenesulfonyl）-glutamine, was synthesized and its structure was confirmed by IB, MS, ^1H NMB, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2（ 1 ）, with a =0. 69281 （ 11 ） nm, b = 0. 76508（12）, c = 1. 5843（3） nm, α=90°, β =90. 941 （3）°, γ =90°, V=0. 8397（2） nm^3, Z =-2, Dc = 1.477 g/cm^3,μ =0. 236 mm^-1, F（000） =392, R =0. 0297, and wR=0.0664.

关键词： 5 -N-i-Propyl-2-( 2' -nitrobenzenesulfonyl) -glutamine Synthesis Crystal structure

Underwater Digital Terrain Model with GPS-aided High-resolution Profile-scan Sonar Images

在线全文

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2008年第2期13卷 233-238页

作者：周拥军寇新建 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

The whole procedures of underwater digital terrain model (DTM) were presented by building with the global positioning system (GPS) aided high-resolution profile-scan sonar *** algorithm regards the digital image scanned in a cycle as the raw *** the label rings are detected with the improved Hough transform (HT) method and followed by curve-fitting for accurate location;then the most probable window for each ping is detected with weighted neighborhood gray-level co-occurrence matrix;and finally the DTM is built by integrating the GPS data with sonar data for 3D *** case of an underwater trench for immersed tube road tunnel is illustrated.

关键词： digital terrain model high-resolution sonar Hough transform neighborhood gray-level co-occurrence matrix

First Passage Probability of Structures under Non-Gaussian Stochastic Behavior

在线全文

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2008年第4期13卷 400-403页

作者：何军周拥军寇新建 Department of Civil Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiaotong University

An analytical moment-based method was proposed for calculating first passage probability of structures under non-Gaussian stochastic behaviour. In the method, the third-moment standardization that con- stants can be obtained from first three-order response moments was used to map a non-Gaussian structural response into a standard Gaussian process; then the mean up-crossing rates, the mean clump size and the initial passage probability of some critical barrier level by the original structural response were estimated. Finally, the formula for calculating first passage probability was established on the assumption that the corrected up-crossing rates are independent. By a nonlinear single-degree-of-freedom system excited by a stationary Gaussian load, it is demonstrated how the procedure can be used for the type of structures considered. Further, comparisons between the results from the present procedure and those from Monte-Carlo simulation are performed.

关键词： first passage probability stochastic process non-Gaussian structures third-moment standardization

Mutual regulation between microRNA-373 and methyl-CpGbinding domain protein 2 in hilar cholangiocarcinoma

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2012年第29期18卷 3849-3861页

作者： yong-jun Chen jian Luo Guang-Yao Yang Kang Yang Song-Qi Wen Sheng-Quan Zou Department of Biliary-pancreatic Surgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM:To investigate the reciprocal modulation between microRNA(miRNA) and DNA methylation via exploring the correlation between miR-373 and methyl-CpGbinding domain protein(MBD)***:MiR-373 expression was examined using the TaqMan miRNA *** of miR-373 was investigated using methylation-specific polymerase chain reaction,and recruitment of methyl binding proteins was studied using the chromatin immunoprecipitation *** analysis was conducted using the QuikChange Site-Directed Mutagenesis *** activity of miR-373 gene promoter constructs and targeting at MBD2-three prime untranslated region(3'UTR) by miR-373 were evaluated by a dual-luciferase reporter gene ***:In hilar cholangiocarcinoma,miR-373 decreased and was closely associated with poor cell differentiation,advanced clinical stage,and shorter *** promoter-associated CpG island of miR-373 gene was hypermethylated and inhibited expression of ***2 was up-regulated and enriched at the promoter-associated CpG island of ***-mediated suppression of miR-373 required MBD2 enrichment at the promoter-associated CpG island,and miR-373 negatively regulated MBD2 expression through targeting the 3'***:MiR-373 behaves as a direct transcriptional target and negative regulator of MBD2 activity through a feedback loop of CpG island methylation.

关键词： MicroRNA-373 Methyl-CpG binding domain proteins 2 Methylation Hilar cholangiocarcinoma Three prime untranslated region

Two-dimensional electrophoresis for comparative proteomic analysis of human bile

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2007年第4期6卷 402-406页

作者： Bo Chen,Jing-Qing Dong,yong-jun Chen,jian-Ming Wang,jun Tian,Chun-Ben Wang and Sheng-Quan Zou Department of General Surgery,Tongji Hospital and Department of Proteomics Research Center,Tongji Medical College,Huazhong University of Science and Technology,Wuhan 430030,China Department of General Surgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China.

BACKGROUND:Proteomic analysis of bile fluid holds promise as a method to identify biomarkers of bile tract diseases,especially for tumors. Two-dimensional electrophoresis(2-DE) is a popular and proven separation technique for proteome analysis,but using this strategy for bile fluid analysis is still not fully developed. This study was undertaken to(a) establish a reliable method for general clean-up to make bile fluid samples suitable for 2-DE;(b) obtain 2-D biliary maps with high reproducibility and resolution;and(c) identify protein patterns present in 2-D biliary maps for potential tumor biomarker discovery,with the intention of distinguishing malignant from benign causes of bile duct obstruction. METHODS:Bile fluid samples were obtained from two patients suffering from malignant and benign bile tract obstruction(one patient with cholangiocarcinoma as the experimental case,the other with cholelithiasis as control). A variety of sample preparation options,including delipidation,desalination and nucleic acid removal,were adopted to remove contaminants that affect 2-DE results. After that,each 350 μg purified sample was loaded onto nonlinear IPG strips(18 cm,pH 3-10 and pH 4-7) for first-dimension isoelectric focusing,and 12.5% SDS-PAGE electrophoresis for second dimension separation. Then 2-D maps were visualized after silver staining and analyzed with the Image Master 2-D software. RESULTS:A large number of protein spots were separated in 2-D maps from the experimental and control groups,with means of 250 and 216 spots on pH 3-10 IPG strips,and 182 and 176 spots on pH 4-7 strips,respectively. Approximately 16 and 23 spots were differentially expressed in matched pairs from the experimental and control cases using pH 3-10 and pH 4-7 strips. CONCLUSIONS:This study established a reliable sample preparation process suitable for 2-DE of bile fluid. By this method,2-D biliary maps with high reproducibility and resolution were obtained. The differentially displayed prote

关键词： proteome electrophoresis,gel,two-dimensional bile