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Exact solutions for the flow of non-Newtonian fluid with fractional derivative in an annular pipe

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 485-495页

作者： TONG Dengke WANG Ruihe YANG Heshan Institute of Mathematics and Computional Science University of Petroleum Beijing 102249 China Institute of Mathematics and Computional Science University of Petroleum Beijing 102249 China Institute of Mathematics and Computional Science University of Petroleum Beijing 102249 China

This paper deals with some unsteady unidirectional transient flows of Oldroyd-B fluid in an annular pipe. The fractional calculus approach in the constitutive relationship model Oldroyd-B fluid is introduced and a generalized Jeffreys model with the fractional calculus has been built. Exact solutions of some unsteady flows of Oldroyd-B fluid in an annular pipe are obtained by using Hankel transform and Laplace transform for fractional calculus. The following four problems have been studied: (1) Poiseuille flow due to a constant pressure gradient; (2) axial Couette flow in an annulus; (3) axial Couette flow in an annulus due to a longitudinal constant shear; (4) Poiseuille flow due to a constant pressure gradient and a longitudinal constant shear. The well-known solutions for Navier-Stokes fluid, as well as those corresponding to a Maxwell fluid and a second grade one, appear as limited cases of our solutions.

关键词： fractional calculus, generalized Oldroyd-B fluid, exact solutions, velocity fields.

Convective heat transfer enhancement of laminar flow of latent functionally thermal fluid in a circular tube with constant heat flux: internal heat source model and its application

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Science China(Technological Sciences) 2003年第2期46卷 131-140页

作者：张寅平胡先旭郝磬王馨 ZHANG Yinping HU Xianxu HAO Qing & WANG Xin Department of Building Science Tsinghua University

This paper analyzes the convective heat transfer enhancement mechanism of latent heat functionally thermal fluid. By using the proposed internal heat source model, the influence of each factor affecting the heat transfer enhancement of laminar flow in a circular tube with constant heat flux is analyzed. The main influencing factors and the mechanisms of heat transfer enhancement are clarified, and the influences of the main factors on the heat transfer enhancement are quantitatively analyzed. A modified Nusselt number for internal flow is introduced to describe more effectively the degree of heat transfer enhancement for latent functionally thermal fluid.

关键词： latent functionally thermal fluid, heat transfer enhancement, microcapsule, phase change.

Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science China Earth Sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Beijing Institute of Geology for Mineral Resources, Beijing 100012, China Correspondence should be addressed to Wang Lijuan (email: wlj@***) Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Beijing Institute of Geology for Mineral Resources Beijing China

fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North China Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Electrorheological fluid of kaolinite-based ternary nanocomposite and its properties

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Science China(Technological Sciences) 2005年第5期48卷 496-509页

作者： WANG Baoxiang ZHAO Xiaopeng YAO Yuan Institute of Electrorheological Technology Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China Institute of Electrorheological Technology Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China Institute of Electrorheological Technology Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China

According to the physical and chemical design, a kind of kaolinite /dimethylsulfoxide/carboxymethyl starch (CMS) ternary nanocomposite was prepared by the two-step composite method. Firstly, the polar liquid-dimethylsulfoxide (DMSO) was directly intercalated into the interlayer of kaolinite, and then the intercalated complex was composite with CMS by the solution method. The results showed that DMSO moderately intercalated the interlayer of kaolinite and the basal spacing of kaolinite was swollen from 0.715 to 1.120 nm. Under the electric fields of 5 kV mm-1 and volume fraction 30%, the static shear stress of kaolinite/DMSO/CMS ternary ERF could reach 17 kPa, which was 14 times and 4.25 times higher than that of pure kaolinite ERF and kaolinite/CMS ERF respectively. At the suitable component ratio (kaolinite:DMSO:CMS=1:0.75:0.6) of nanocomposite, a stronger synergetic effect and the optimum electrorheological effect could be attained. The ternary nanocomposite ERF also had good temperature effect and sedimentation properties. The sedimentation part of ternary nanocomposite ERF was only 9% after 30 days. The results of dielectric properties showed that the dielectric constant and conductivity of ternary nanocomposite ERF had been improved more enormously than that of the single component ERF and binary composite ERF. So the polarization and dielectric mismatch were strengthened, which was suitable to the enhancement of ER effect.

关键词： electrorheological fluid, intercalation, ternary system, nanocomposite.

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science China Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2, HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment Science, Hebei University, Baoding 071002, China 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China 3. College of Physics Science and Technology, Hebei University, Baoding 071002, China College of Chemistry and Environment Science Hebei University Baoding China International Center for Materials Physics Chinese Academy of Sciences Shenyang China College of Physics Science and Technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

fluid flow and mineralization of Youjiang Basin in the Yunnan-Guizhou-Guangxi area, China

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Science China Earth Sciences 2003年第Z1期46卷 99-109页

作者：王国芝胡瑞忠苏文超朱赖民 Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Chengdu University of Technology Chengdu 610059 China

Comprehensive studies, based on isotope geochemistry of C, H, O, S and Sr, chronology, common element and trace element geochemistry of fluid inclusions for the epithermal Au, As, Sb and Hg deposits in the Youjiang Basin and its peripheral areas, suggested that the ore fluid was the basin fluid with abundant metallic elements and the large-scale fluid flow of the same source in the late Yenshan stage was responsible for huge epithermal mineralization and silicification. The ore fluid flowed from the basin to the platform between the basin and the platform and migrated from the inter-platform basin to the isolated platform in the Youjiang Basin. The synsedimentary faults and paleokast surface acted respectively as main conduits for vertical and lateral fluid flow.

关键词： Youjiang Basin, basin fluid, fluid flow, epithermal mineralization.

Isolation of Cell-Free DNA from Seminal fluid

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Journal of Pharmacy and Pharmacology 2017年第8期5卷 554-560页

作者： Tina Draskovic Faculty of Pharmaciy University of Ljubljana Ljubljana 1000 Slovenia

Cell-flee DNA （cfDNA） is small short double stranded molecule that is also found in seminal fluid. It is a product ofapoptotic cells in different developmental stages during spermatogenesis. To final concentration of total cfDNA in semen contributesalso cfDNA secreted from living cells and cfDNA that is result of different diseases e.g. prostate cancer or infertility. Amendedconcentration （high or low） can be connected to prostate cancer or male infertility and can represent important non-invasive diagnosticbiomarker for detection and prognosis of these pathological conditions. In this paper, I will discuss different approaches for isolation ofcfDNA from seminal fluid, which includes selection of the samples, separation, isolation, extraction, purification and analysis. Today＇smost popular approach for isolation is the use of commercial kits based on selective binding and elution on silica-membrane technology,magnetic-bead technology or extraction with organic solvents and salting out procedure. Furthermore I will present that I tried to isolatecfDNA from semen with QIAamp DNA Mini Kit to confirm the presence of cell-free DNA in our samples. In the end I will describeproblems we are facing during cfDNA measurement which are mainly associated with low concentration of cfDNA in samples.

关键词： Cell-free DNA, seminal fluid, diagnostic biomarker, prostate cancer, male infertility, cell-free DNA isolation, problems ofcell-free DNA measurement.

Basical characteristics of fluid geologic process of interlayer oxidation zone sandstone-typeuranium deposit

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Science China Earth Sciences 2007年第Z2期50卷 185-194页

作者： WU BoLin LIU ChiYang WANG JianQiang State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China

This paper reveals the physicochemical properties such as component, formulation, genesis, tem- perature, pH, Eh, salinity and pressure of all main alteration fluid of interlayer oxidation zone sand- stone-type uranium deposits after studying the geologic process and geochemistry of internal typical sandstone-type uranium deposits such as Shihongtan deposit in the Turpan-Hami basin, 512 deposit in the Yili basin, Dongsheng deposit in the Ordos basin. The composition of fluid can be divided into two parts based on the analysis of inclusion: one can be affirmed as atmospheric water with ordinary temperature epigenesist according to the character of hydrogen and oxygen isotope of inclusion, the other is natural gas containing gaseous hydrocarbon like CH4, and CO2 as well as a little H2S, CO, H2, N2 and so on, it always contains a small quantity of hydrocarbon liquid in petroliferous basins. The fluid property of oxidation alteration zone is always oxidation alkaline, and neutrality or weak acid-weak alkaline and reducibility during the metallizing process, but at secondary reduction or deoxidization zone it becomes strong reduction alkaline. Oxygenic groundwater in the fluid is the activate and mig- ratory medium of uranium element, but the gaseous hydrocarbon like CH4 as well as H2, H2S, CO from natural gas is the important sedimentary reducer of uranium mineral; the transformation of pH,Eh in fluid environment is the main reason for the formation of uranium metallization.

关键词： fluid, interlayer oxidation zone, uranium deposit, inclusion, isotope

Magnetohydrodynamic approach of non-Newtonian blood flow with magnetic particles in stenosed artery

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Applied Mathematics and Mechanics(English Edition) 2017年第3期38卷 379-392页

作者： I. A. MIRZAt M. ABDULHAMEED S. SHAFIE Abdus Salam School of Mathematical Sciences Government College University Lahore 54000 Pakistan School of Science and Technology Federal Polytechnic P. M. B. Bauchi 0231 Nigeria Department of Mathematical Sciences Faculty of Science Universiti Teknologi Skudai 81310 Malaysia

The non-Newtonian blood flow, together with magnetic particles in a stenosed artery, is studied using a magneto-hydrodynamic approach. The wall slip condition is also considered. Approximate solutions are obtained in series forms under the assumption that the Womersley frequency parameter has small values. Using an integral transform method, analytical solutions for any values of the Womersley parameter are *** simulations are performed using MATHCAD to study the influence of stenosis and magnetic field on the flow parameters. When entering the stenosed area, blood velocity increases slightly, but increases considerably and reaches its maximum value in the stenosis throat. It is concluded that the magnitude of axial velocity varies considerably when the applied magnetic field is strong. The magnitude of maximum fluid velocity is high in the case of weak magnetic fields. This is due to the Lorentz's force that opposes motion of an electrically conducting fluid. The effect of externally transverse magnetic field is to decelerate the flow of blood. The shear stress consistently decreases in the presence of a magnetic field with increasing intensity.

关键词： Bingham plastic fluid, magnetic particle, blood flow, magnetohydrodynam-ics, artery stenosis