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Lattice Boltzmann simulation of solute transport in a single rough fracture

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Water Science and Engineering 2014年第3期7卷 277-287页

作者： zhi DOU zhi-fang ZHOU School of Earth Sciences and Engineering Hohai University

In this study, the lattice Boltzmann method （LBM） was used to simulate the solute transport in a single rough fracture. The self-affine rough fracture wall was generated with the successive random addition method. The ability of the developed LBM to simulate the solute transport was validated by Taylor dispersion. The effect of fluid velocity on the solute transport in a single rough fracture was investigated using the LBM. The breakthrough curves （BTCs） for continuous injection sources in rough fractures were analyzed and discussed with different Reynolds numbers （Re）. The results show that the rough frac~＇e wall leads to a large fluid velocity gradient across the aperture. Consequently, there is a broad distribution of the immobile region along the rough fracture wall. This distribution of the immobile region is very sensitive to the Re and fracture geometry, and the immobile region is enlarged with the increase of Re and roughness. The concentration of the solute front in the mobile region increases with the Re. Furthermore, the Re and roughness have significant effects on BTCs, and the slow solute molecule exchange between the mobile and immobile regions results in a long breakthrough tail for the rough fracture. This study also demonstrates that the developed LBM can be effective in studying the solute transport in a rough fracture.

关键词： solute transport single rough fracture Lattice Boltzmann method, self-affinity breakthrough curve

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腰椎间盘突出症模型大鼠疼痛的针刺干预

中国组织工程研究 2025年第5期29卷 936-941页

作者：支芳朱满华熊伟林星镇南昌市洪都中医院江西省南昌市330038

背景:针灸是缓解腰椎间盘突出症腰痛的有效方法,但其机制目前尚未明确。JAK2/STAT3信号通路相关因子可调节机体炎症反应,参与神经病理性疼痛的过程。目的:基于JAK2/STAT3信号通路研究针刺对腰椎间盘突出症模型大鼠的作用机制。方法:采... 详细信息

背景:针灸是缓解腰椎间盘突出症腰痛的有效方法,但其机制目前尚未明确。JAK2/STAT3信号通路相关因子可调节机体炎症反应,参与神经病理性疼痛的过程。目的:基于JAK2/STAT3信号通路研究针刺对腰椎间盘突出症模型大鼠的作用机制。方法:采用随机数字表法将40只SD大鼠分为假手术组、模型组、针刺组与针刺+激动剂组,每组10只。模型组、针刺组及针刺+激动剂组采用自体髓核移植法构建L5腰椎间盘突出症模型,造模3 d后,针刺组开始进行针刺治疗(作用于阳陵泉、肾俞、环跳、大肠俞等穴位),针刺+激动剂组造模后第6,12,18天针刺治疗前向L4/L5椎间隙鞘内注射JAK2激动剂香豆霉素A1,针刺治疗1次/d,20 min/次,连续治疗15 d。造模前及造模后3,6,9,12,15,18 d,检测大鼠机械缩足阈值;造模后18 d,检测血清炎症因子水平,苏木精-伊红染色观察L5-L6组织形态,RT-PCR检测L5-L6组织JAK2、STAT3 mRNA表达,Western Blot检测L5-L6组织JAK2、STAT3、p-JAK2及p-STAT3蛋白表达。结果与结论:①模型组大鼠造模后不同时间点的机械缩足阈值均低于假手术组(P<0.05),针刺组大鼠造模后9,12,15,18 d的机械缩足阈值均高于模型组(P<0.05),针刺+激动剂组大鼠造模后9,12,15,18 d的机械缩足阈值均低于针刺组(P<0.05);②与假手术组比较,模型组白细胞介素6、肿瘤坏死因子α、神经递质P物质、脑部神经肽Y水平均升高(P<0.05);与模型组比较,针刺组4种炎症因子水平均降低(P<0.05);与针刺组比较,针刺+激动剂组4种炎症因子水平均升高(P<0.05);③苏木精-伊红染色显示模型组大鼠腰椎退行性变化明显,针刺组与针刺+激动剂组大鼠腰椎退行性变化减轻,针刺组减轻更明显;④与假手术组比较,模型组JAK2与STAT3 mRNA表达、p-JAK2与p-STAT3蛋白表达均升高(P<0.05);与模型组比较,针刺组JAK2与STAT3 mRNA表达、p-JAK2与p-STAT3蛋白表达均降低(P<0.05);与针刺组比较,针刺+激动剂组JAK2与STAT3 mRNA表达、p-JAK2与p-STAT3蛋白表达均升高(P<0.05);⑤结果表明,针刺干预可通过降低腰椎间盘突出症模型大鼠的炎症反应来缓解疼痛,其作用机制可能与抑制JAK2/STAT3信号通路有关。

关键词： JAK2/STAT3信号通路针刺腰椎间盘突出症病理性疼痛机械缩足阈值炎症反应

NUMERICAL STUDY OF NON-AQUEOUS PHASE LIQUID TRANSPORT IN A SINGLE FILLED FRACTURE BY LATTICE BOLTZMANN METHOD

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Journal of Hydrodynamics 2012年第1期24卷 130-137页

作者： DOU zhi ZHOU zhi-fang HUANG Yong WU Wei School of Earth Science and Engineering Hohai UniversityNanjing 210098China School of Materials Science and Engineering Southeast UniversityNanjing 211189China

In this article,the Non-Aqueous Phase Liquid（NAPL）transport in the single filled fracture was studied with the Shan-Chen multi-component multiphase Lattice Boltzmann Method（LBM）with special consideration of wettability *** the help of the model,the contact angle of the non-wetting phase and wetting phase interface at a solid wall could be *** considering a set of appropriate boundary conditions,the fractured conductivity was investigated in condition that the NAPL blocks the channels in the single filled *** order to study the wettability effects on the NAPL transport,a constant driving force was introduced in the Shan-Chen multi-component multiphase *** regimes with different wettabilities were *** results show that the LBM is a very instrumental method for simulating and studying the immiscible multiphase flow problems in single filled fracture.

关键词： single filled fracture Lattice Boltzmann Method(LBM) Non-Aqueous Phase Liquid(NAPL)transport wettability contact angle immiscible two-phase flow

Experimental study on shear behavior of prestressed reactive powder concrete I-girders

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 618-627页

作者： Hui ZHENG zhi fang Bin CHEN College of Civil Engineering Hunan University of TechnologyZhuzhou 412007China College of Civil Engineering Hunan UniversityChangsha 410082China

As a new generation of concrete,RPC(Reactive Powder Concrete)has attracted great research attention for its ultra-high strength and high *** the present paper,experimental results from tests on eight prestressed RPC I-section girders failing in shear are reported *** beams with RPC of 120 MPa in compression were designed to assess the ability to carry shear stress in thin webbed prestressed beams with *** test variables were the level of prestressing,shear span-depth ratio(a/d)and stirrup *** deformation,shear capacity and crack pattern were experimentally investigated in *** regard to the shear resistance of the test beams,the predictions from three standards(AFGC,JSCE and SIA)on the design of UHPC structures were compared with the experimental result suggesting that the experimental strength is almost always higher than ***,as a new concrete,was different from normal concrete and fiber reinforced *** study should be needed to develop an analytical method and computation model for shear strength of RPC beams.

关键词： prestressed concrete RPC(Reactive Powder Concrete) concrete beams shear strength experimental study

Theoretical Study on the Catalytic Activity and Sulfur Resistibility of Amorphous Alloy Ni-B-P

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Chinese Journal of Structural Chemistry 2007年第3期26卷 273-280页

作者： fang zhi-Gang GUO Jing-Xue School of Chemical Engineering University of Science and Technology Liaoning Anshan 114051 China

In the present paper, one hundred cluster models NinBP （n = 1-6） have been designed and studied by density functional theory （DFT） to get an insight into the local structure, catalytic properties and sulfur resistibility of amorphous alloy Ni-B-P. The configurations in triplet state are found more stable than those in the singlet state. It is found： that as the content of Ni in the clusters increases, the value of Fermi level in clusters fluctuated, which shows that the content of Ni can influence the Fermi level to a certain extent. Based on the Fermi level and DOS, we consider the activity of catalyst in hydrogenation reaction is the best in cluster Ni3BP. On the basis of the charge of clusters NinBP （n = 1 -6）, we conclude the amorphous alloy Ni-B-P with high Ni content has better sulfur resistibility and the best hydrogenation activity, strong sulfur resistibility appears in clusters Ni3BP, and the amorphous alloy Ni60B20P20 with similar proportion is expected to prepare in the future.

关键词： amorphous alloy Ni-B-P DFT catalytic activity sulfur resistibility

Special issue on selected papers from HVDP 2016

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Plasma Science and Technology 2017年第6期19卷 1-2页

作者： zhi fang Cheng CHENG College of Electrical Engineering and Control Science Nanjing Tech University Institute of Plasma Physics Chinese Academy of Sciences

This special issue contains selected papers from the 2016 National Conference on High Voltage and Discharge Plasmas（HVDP）,which was hosted by the Plasmas and their Applications Committee,China Electrotechnical Society,and held in Beijing,China,on 26 and 27 November *** conference was attended by over 430 delegates from 110 universities,research institutes and *** total,280 abstracts and 132 full papers have been submitted,giving a wonderful assembly of technical contributions from around China.

关键词： this Special issue on selected papers from HVDP 2016

Variable Separation Solution for （1＋1）-Dimensional Nonlinear Models Related to Schroedinger Equation

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Communications in Theoretical Physics 2004年第4X期42卷 568-572页

作者： XUChang-zhi ZHANGJie-fang InstituteofNonlinearPhysics ZhejiangNormalUniversityJinhua321004China

A variable separation approach is proposed and successfully extended to the (1+1)-dimensional physics models. The new exact solution of (1+1)-dimensional nonlinear models related to Schr6dinger equation by the entrance of three arbitrary functions is obtained. Some special types of soliton wave solutions such as multi-soliton wave solution,non-stable soliton solution, oscillating soliton solution, and periodic soliton solutions are discussed by selecting the arbitrary functions appropriately.

关键词：变量分析近似孤立子解二维非线性模型非线性物理薛定谔方程随机函数

Three-dimensional analysis of spreading and mixing of miscible compound in heterogeneous variable-aperture fracture

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Water Science and Engineering 2016年第4期9卷 293-299页

作者： zhi Dou zhi-fang Zhou Jin-guo Wang Department of Civil Engineering University of Toronto School of Earth Sciences and Engineering Hohai University

As mass transport mechanisms,the spreading and mixing(dilution) processes of miscible contaminated compounds are fundamental to understanding reactive transport behaviors and transverse *** this study,the spreading and dilution processes of a miscible contaminated compound in a three-dimensional self-affine rough fracture were simulated with the coupled lattice Boltzmann method(LBM).Moment analysis and the Shannon entropy(dilution index) were employed to analyze the spreading and mixing processes,*** corresponding results showed that the spreading process was anisotropic due to the heterogeneous aperture distribution.A compound was transported faster in a large aperture region than in a small aperture region due to the occurrence of preferential *** the spreading and mixing processes were highly dependent on the fluid flow velocity and molecular *** calculated results of the dilution index showed that increasing the fluid flow velocity and molecular diffusion coefficient led to a higher increasing rate of the dilution index.

关键词： Mixing Spreading Solute transport Three-dimensional fracture Self-affinity Hurst exponent

Integration of a Nonlinear Vibration Absorber and Levitation Magnetoelectric Energy Harvester for Whole-Spacecraft Systems

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Acta Mechanica Solida Sinica 2019年第3期32卷 298-309页

作者： Ye-Wei Zhang zhi-Wei fang Shi-Lei Wang zhi-Yu Ni Jian Zang Bo fang College of Aerospace Engineering Shenyang Aerospace University Shenyang 110136 China Shanghai Prime Machinery Company Limited Shanghai 200072 China

This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger energy harvesting capability than the existing systems. It harvests energy from a wide frequency range and has a high output voltage. The harvested energy is determined by magnetic field strength, excitation frequency, and resistive load. The change in the magnetic field strength has the least impact on the output voltage. The vibration reduction effects and harvested energy of the system are analyzed with an approximate analytical method that combines the harmonic balance approach and the pseudo-arclength continuation algorithm. The results of the Runge-Kutta method are nearly consistent with those of the approximate analytical method. Moreover, the effects of the excitation frequency, resistive load, and parameters of the nonlinear energy sink on the system vibration response and energy harvesting are analyzed.

关键词： Levitation magnetoelectric energy harvester Whole spacecraft Nonlinear energy sink Vibration reduction