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Partial slip effect on non-aligned stagnation point nanofluid over a stretching convective surface 被引量:2
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作者 S.Nadeem Rashid Mehmood Noreen Sher Akbar 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期369-376,共8页
The present study inspects the non-aligned stagnation point nano fluid over a convective surface in the presence of partial slip. Two types of base fluids namely water and kerosene are selected with Cu nanoparticles. ... The present study inspects the non-aligned stagnation point nano fluid over a convective surface in the presence of partial slip. Two types of base fluids namely water and kerosene are selected with Cu nanoparticles. The governing physical problem is presented and transformed into a system of coupled nonlinear differential equations using suitable similarity transformations. These equations are then solved numerically using midpoint integration scheme along with Richardson extrapolation via Maple. Impact of relevant physical parameters on the dimensionless velocity and temperature profiles are portrayed through graphs. Physical quantities such as local skin frictions co-efficient and Nusselt numbers are tabularized.It is detected from numerical computations that kerosene-based nano fluids have better heat transfer capability compared with water-based nanofluids. Moreover it is found that water-based nanofluids offer less resistance in terms of skin friction than kerosene-based fluid. In order to authenticate our present study, the calculated results are compared with the prevailing literature and a considerable agreement is perceived for the limiting case. 展开更多
关键词 partial slip non-aligned stagnation point NANOFLUID stretching convective surface
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Hydromagnetic thin film flow of Casson fluid in non-Darcy porous medium with Joule dissipation and Navier's partial slip
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作者 G.S.SETH R.TRIPATHI M.K.MISHRA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第11期1613-1626,共14页
In this paper, the effects of viscous and Ohmic heating and heat genera- tion/absorption on magnetohydrodynamic flow of an electrically conducting Casson thin film fluid over an unsteady horizontal stretching sheet in... In this paper, the effects of viscous and Ohmic heating and heat genera- tion/absorption on magnetohydrodynamic flow of an electrically conducting Casson thin film fluid over an unsteady horizontal stretching sheet in a non-Darcy porous medium are investigated. The fluid is assumed to slip along the boundary of the sheet. Similar- ity transformation is used to translate the governing partial differential equations into ordinary differential equations. A shooting technique in conjunction with the 4th order Runge-Kutta method is used to solve the transformed equations. Computations are car- ried out for velocity and temperature of the fluid thin film along with local skin friction coefficient and local Nusselt number for a range of values of pertinent flow parameters. It is observed that the Casson parameter has the ability to enhance free surface velocity and film thickness, whereas the Forchheimer parameter, which, is responsible for the inertial drag has an adverse effect on the fluid velocity inside the film. The velocity slip along the boundary tends to decrease the fluid velocity. This investigation has various applications in engineering and in practical problems such as very large scale integration (VLSI) of electronic chips and film coating. 展开更多
关键词 fluid thin film non-Darcy medium velocity slip unsteady stretching sheet Joule dissipation heat generation/absorption
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Numerical Modeling of Non-Similar Mixed Convection Heat Transfer over a Stretching Surface with Slip Conditions
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作者 A. Subba Rao V. R. Prasad +3 位作者 N. Nagendra K. V. N. Murthy N. Bhaskar Reddy O. Anwar Beg 《World Journal of Mechanics》 2015年第6期117-128,共12页
In this paper, the heat transfer effect on the steady boundary layer flow of a Casson fluid past a stretching surface in the presence of slip conditions was analyzed. The stretching surface is maintained at a constant... In this paper, the heat transfer effect on the steady boundary layer flow of a Casson fluid past a stretching surface in the presence of slip conditions was analyzed. The stretching surface is maintained at a constant temperature. The boundary layer conservation equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller-box finite difference scheme. The resulting equations are solved numerically by using the Kellerbox finite-difference method, and the expressions for velocity and temperature are obtained. They satisfy all imposed initial and boundary conditions and reduce to some well-known solutions for non-Newtonian fluids. Numerical results for velocity, temperature, skin friction and Nusselt number are shown in various graphs and discussed for embedded flow parameters. It is found that both velocity and temperature decrease with an increase of the Casson fluid parameter. 展开更多
关键词 STRETCHING Surface non-Newtonian Fluid slip Condition Keller-Box NUMERICAL Method Heat Transfer SKIN Friction Coefficient
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肥胖儿童non-HDL-C、remnant cholesterol与亚临床动脉粥样硬化的关系 被引量:4
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作者 焦朝艳 刘戈力 +4 位作者 鲍鹏丽 魏莹 杨箐岩 郑荣秀 赵菁 《天津医科大学学报》 2014年第1期25-28,共4页
目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体... 目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体质量儿童30例为III组(对照组)。比较3组儿童血脂指标,对肥胖组各项血脂指标与血浆致动脉粥样硬化指数(AIP)进行相关性分析,肥胖患儿体质指数、血脂指标与颈动脉内径、内膜-中层厚度(c-IMT)、血流参数进行相关性分析。结果:I组、II组的TG、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、non-HDL-C、remnant cholesterol、AIP均较对照组升高,高密度脂蛋白胆固醇(HDL-C)较对照组降低,且I组的remnant cholesterol、AIP均较II组升高。肥胖组儿童AIP与TG、non-HDL-C、remnant cholesterol呈正相关,与HDL-C呈负相关。37例行颈动脉超声检查的肥胖儿童的c-IMT较正常儿童的增厚。结论:non-HDL-C、remnant cholesterol在肥胖儿童亚临床AS中有重要作用,在肥胖儿童血脂异常的治疗中应关注non-HDL-C、remnant cholesterol的变化。 展开更多
关键词 儿童肥胖 亚临床动脉粥样硬化 non—HDL—C REMNANT CHOLESTEROL 血浆致动脉粥样硬化指数 颈动脉内膜-中层厚度
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Flow behavior in microchannel made of different materials with wall slip velocity and electro-viscous effects 被引量:5
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作者 Lei Wang Jiankang Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期73-80,共8页
In a microfluidic system, flow slip velocity on a solid wall can be the same order of magnitude as the average velocity in a microchannel. The flow-electricity interaction in a complex microfluidic system subjected to... In a microfluidic system, flow slip velocity on a solid wall can be the same order of magnitude as the average velocity in a microchannel. The flow-electricity interaction in a complex microfluidic system subjected to joint action of wall slip and electro-viscous effect is an important topic. This paper presents an analytic solution of pressuredriven liquid flow velocity and flow-induced electric field in a two-dimensional microchannel made of different materials with wall slip and electro-viscous effects. The Poisson- Boltzmann equation and the Navier-Stokes equation are solved for the analytic solutions. The analytic solutions agree well with the numerical solutions. It was found that the wall slip amplifies the fow-induced electric field and enhances the electro-viscous effect on flow. Thus the electro-viscous effect can be significant in a relatively wide microchannel with relatively large kh, the ratio of channel width to thickness of electric double layer, in comparison with the channel without wall slip. 展开更多
关键词 MICROCHANNEL Wall slip - Electro-viscous effects
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Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced non-small cell lung cancer: a meta-analysis 被引量:13
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作者 Qiang Zhang Yi-Huan Fan +2 位作者 Teng Zhang Xiao-Lan Qin Ji-Fang Song 《TMR Integrative Medicine》 2017年第2期68-78,共11页
Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a syst... Objective: To evaluate the clinical efficacy of Shenqi Fuzheng injection combined with gemcitabine plus cisplatin(GP) in the treatment of advanced non-small cell lung cancer (NSCLC). Methods: we performed a systematicsearch in the electronic databases such as Cochrane Library, Pubmed, Embase, Chinese Journal Full-text Database,Chinese Biomedical Literature Database, Chinese Science and Technology Periodical Full-text Database andWanfang Database up to 30 January 2017. Randomized controlled trials (RCT) of Shenqi Fuzheng Injectioncombined with GP chemotherapy in the treatment of advanced NSCLC were searched, and all the RCTs wereconducted on methodological quality assessment. Data extraction and data analysis were according to standards ofCochrane systematic review. Results: Eight trials were included including a total of 701 patients. Meta-analysisresults: Shenqi Fuzheng injection combined with GP chemotherapy could significantly improve the functionalstatus of patients with NSCLC (OR = 3.44, 95% CI [2.26, 5.25], P 〈 0.0001) and clinical treatment efficacy (OR =(OR = 0.31, 95%CI [0.20, 0.47], P 〈 0.0001. The rate of leukopenia (OR = .31, 95%CI [0.20,0.47], P 〈 0.0001),thrombocytopenia (OR = 0.58, 95%CI [0.37, 0.91], P = 0.020), hemoglobin decline ((OR = 0.31, 95%CI [0.16,0.59], P = 0.0004) and incidence of gastrointestinal reactions (OR = 0.58,P 〈 0.05) could be reduced. Conclusion:Shenqi Fuzheng injection combined with GP chemotherapy in the treatment of advanced NSCLC obtainedsignificantly clinical efficacy. The quality of the literature incorporated is low, the conclusion requires high-qualityresearch to further prove. 展开更多
关键词 Shenqi Fuzheng GP chemotherapy Advanced non - small cell lung cancer Meta analysis
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带有两个物体的Burridge-Knopoff模型的stick-slip运动
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作者 张继锋 冯奇 《振动工程学报》 EI CSCD 北大核心 2007年第5期480-483,共4页
Burridge-Knopoff模型是研究地震机理的一种摩擦动力系统模型。考察了具有两个自由度的Burridge-Knopoff模型的摩擦激振问题。系统带有两个摩擦接触面,摩擦采用带有负斜率的速度依赖型摩擦曲线。因为摩擦引入的非光滑性,给系统的直接求... Burridge-Knopoff模型是研究地震机理的一种摩擦动力系统模型。考察了具有两个自由度的Burridge-Knopoff模型的摩擦激振问题。系统带有两个摩擦接触面,摩擦采用带有负斜率的速度依赖型摩擦曲线。因为摩擦引入的非光滑性,给系统的直接求解带来了很大的困难;又因为具有两个摩擦接触面,运动情况会更加复杂:物体一的2种形式stick或slip,物体二具有同样的2种形式,从而可组合成4种运动形式的交替运动。首先找到各个运动形式的显式解,再根据各运动形式的跃迁点即可得系统总体的运动。在小的驱动速度下把速度依赖型的摩擦对速度取平均值,近似为动摩擦系数;把位移和速度表达为时间的显式函数。再按位移和速度处于不同运动形式进行迭代求解待定系数。最后由确定的待定系数判断系统运动的性质(周期运动或是混沌运动)。 展开更多
关键词 摩擦激振 - 非光滑 迭代序列
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Imperialistic Competitive Algorithm:A metaheuristic algorithm for locating the critical slip surface in 2-Dimensional soil slopes 被引量:5
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作者 Ali Reza Kashani Amir Hossein Gandomi Mehdi Mousavi 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第1期83-89,共7页
In this study, Imperialistic Competitive Algorithm(ICA) is utilized for locating the critical failure surface and computing the factor of safety(FOS) in a slope stability analysis based on the limit equilibrium ap... In this study, Imperialistic Competitive Algorithm(ICA) is utilized for locating the critical failure surface and computing the factor of safety(FOS) in a slope stability analysis based on the limit equilibrium approach. The factor of safety relating to each trial slip surface is calculated using a simplified algorithm of the Morgenstern-Price method, which satisfies both the force and the moment equilibriums. General slip surface is considered non-circular in this study that is constituted by linking random straight lines.To explore the performance of the proposed algorithm, four benchmark test problems are analyzed. The results demonstrate that the present techniques can provide reliable, accurate and efficient solutions for locating the critical failure surface and relating FOS. Moreover, in contrast with previous studies the present algorithm could reach the lower value of FOS and reached more exact solutions. 展开更多
关键词 Meta-heuristic algorithms Morgen-stern and price method non-circular slip surface Imperialistic competitive algorithm
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Analysis of Numerical Results in High Temperature Congealment and Chemistry Non-equilibrium Flow Field
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作者 Hong-tao Zheng Zhi-yong Tan +2 位作者 Hai-ou Sun Chun-liang Zhou Zhi-ming Li 《Journal of Marine Science and Application》 2002年第1期26-34,共9页
Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved... Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved. In this paper, using internalequivalent heat area in place of electric are that created Ohm heat, the flow fields of thermodynamic equilibrium chemistry con-gealment and chemistry non-equilibrium in the plasma generator were simulated. The influences of the inlet prerotation angleof air, the inlet total pressure of air and the airflow compression angle of spray nozzle on the temperature on the surface of elec- 展开更多
关键词 plasma GENERATOR CHEMISTRY non - EQUILIBRIUM IGNITION technique numerical calculation
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Jeffery-Hamel flow of non-Newtonian fluid with nonlinear viscosity and wall friction 被引量:1
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作者 J. NAGLER 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第6期815-830,共16页
A Jeffery-Hamel (J-H) flow model of the non-Newtonian fluid type inside a convergent wedge (inclined walls) with a wall friction is derived by a nonlinear ordinary differential equation with appropriate boundary c... A Jeffery-Hamel (J-H) flow model of the non-Newtonian fluid type inside a convergent wedge (inclined walls) with a wall friction is derived by a nonlinear ordinary differential equation with appropriate boundary conditions based on similarity relationships. Unlike the usual power law model, this paper develops nonlinear viscosity based only on a tangential coordinate function due to the radial geometry shape. Two kinds of solutions are developed, i.e., analytical and semi-analytical (numerical) solutions with suitable assumptions. As a result of the parametric examination, it has been found that the Newtonian normalized velocity gradually decreases with the tangential direction progress. Also, an increase in the friction coefficient leads to a decrease in the normalized Newtonian velocity profile values. However, an increase in the Reynolds number causes an increase in the normalized velocity function values. Additionally, for the small values of wedge semi-angle, the present solutions are in good agreement with the previous results in the literature. 展开更多
关键词 Jeffery-Hamel (J-H) flow slip condition non-Newtonian fluid friction nonlinear viscosity analytical solution numerical solution approximate solution
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Turbulent Flow Action of Pulp in Wet - Laid Non - Woven Processes
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作者 程隆棣 黄秀宝 于修业 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期57-59,共3页
The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and prac... The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and practice.The suitable use of the imported velocity of pulp is very important in producing wet-laid products of good quality. 展开更多
关键词 WET - laid non - woven fiber PULP FLOW TURBULENT FLOW layer FLUID occluded FLUID .
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CYFRA 21-1 as an early predictor of first line chemotherapy response in advanced non small cell lung cancer
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作者 Kashif Iqbal 《The Chinese-German Journal of Clinical Oncology》 CAS 2007年第3期250-253,共4页
Objective: In an era of ever evolving, promising new therapies for advanced non small cell lung cancer (NSCLC), early predictors of response to therapy, are needed. We evaluated early variations in CYFRA 21-1 serum... Objective: In an era of ever evolving, promising new therapies for advanced non small cell lung cancer (NSCLC), early predictors of response to therapy, are needed. We evaluated early variations in CYFRA 21-1 serum levels of patients with advanced NSCLC receiving first line chemotherapy and correlated the results with objective tumor response. Methods: 29 consecutive, previously untreated, patients of advanced non small cell lung cancer, with measurable disease on CT scan were evaluated. All patients were treated with conventional systemic chemotherapy, although the choice of chemotherapy was left to the discretion of the treating physicians. Serum samples were obtained immediately before the start of 1st and 2nd cycles of chemotherapy. CYFRA 21-1 was measured with an electrochemiluminescense immunoassay on an automatic analyzer (Elecsys 2000; Roche Diagnostics). Response was evaluated using Response evaluation criteria in solid tumors (RECIST) criteria. Results: 10 patients had partial response, 9 patients had stable disease and 9 had progressive disease. None of the patients had complete response. 21/29 (72%) patients had an elevated baseline value of CYFRA 21-1.62% patients (18/29) had a decrease in CYFRA 21-1 after 1 cycle of chemotherapy. The average reduction in the 2nd reading was irrespective of whether baseline value was normal or not. The average reduction was statistically significant (P = 0.002; 95% CI, from 0.8369 to 3.49464; t test). 8 out of 10 (80%) patients with partial response had a reduction in their 2nd reading of. CYFRA (P = 0.019; 95% CI, from 0.81965 to 7.20035; t test) which was significant. We also observed that 6/9 (66%) patients whose disease remains stable also had a decrease in their subsequent reading (P = 0.0106; 95% CI, from -0.44942 to 3.82720; t test), though it was not significant statistically. Although 5 out of 9 (55%) patients, who had an increase in their CYFRA 21-1 level, had progressive disease, but it was not statistically significant (P = 0.537; 95% CI, from -1.20021 to 2.13354; ttest). 14 out of 19 (73%) who either had partial response or had stable disease, had a reduction in their 2nd value of CYFRA 21-1 and was significant statistically (P = 0.004; 95% CI, from 0.74792 to 3.50208; t test). We also observed that except for 1 patient, all patients who had a decrease of 42% or more in their subsequent CYFRA 21-1 level, were those who had either responded to chemotherapy or had stable disease (P = 0.001), which was statistically significant. Conclusion: We can conclude that monitoring of serum marker CYFRA 21-1, early dudng first-line chemotherapy may be a useful prognostic tool for evaluation of early tumor response in patients with advanced NSCLC. 展开更多
关键词 CYFRA 21-1 non small cell lung cancer CHEMOTHERAPY RESPONSE
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考虑黏结-滑移效应的UHPC梁钢筋应力计算方法
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作者 孙永新 蔺鹏臻 杨子江 《西南交通大学学报》 EI CSCD 北大核心 2024年第5期1058-1067,共10页
为建立适用于配筋超高性能混凝土(UHPC)梁的钢筋应力计算方法,对6片UHPC-T形截面梁开展四点弯曲试验,研究钢筋应力的变化规律.从钢筋-UHPC受力平衡与变形协调机理出发,应用微元体建立平衡、变形以及黏结-滑移微分方程,导出能综合反映钢... 为建立适用于配筋超高性能混凝土(UHPC)梁的钢筋应力计算方法,对6片UHPC-T形截面梁开展四点弯曲试验,研究钢筋应力的变化规律.从钢筋-UHPC受力平衡与变形协调机理出发,应用微元体建立平衡、变形以及黏结-滑移微分方程,导出能综合反映钢筋与UHPC界面黏结-滑移影响及钢纤维抗拉贡献的钢筋应力计算公式,并通过简化应变不均匀系数与裂缝截面钢筋应力计算,提出便于工程应用的钢筋应力简化公式.研究表明:单位荷载下钢筋应力的增幅随配筋率的提高而减小,而与钢纤维体积率的变化无关;与普通混凝土梁相比,UHPC梁的钢筋应力在开裂截面处偏小,但其分布在相邻裂缝间的不均匀程度更高;钢筋应力建议公式计算值与本文、既有文献的试验值均吻合良好;钢筋应力简化公式计算值与试验值之比的均值为1.03,变异系数为0.06,表明该简化式可用于UHPC梁的钢筋应力计算. 展开更多
关键词 超高性能混凝土(UHPC) 钢筋应力 黏结-滑移 应变不均匀系数 微元体
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MiR-16-5p plays an inhibitory role in human non-small cell lung cancer through Fermitin family member 2
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作者 JUNQI GUO YUN YANG +6 位作者 WEI ZHAO ZHONGHAI YAN XIA YANG YUNFEI YAN RUIMIN HAO JINXIA HU FEI JIAO 《BIOCELL》 SCIE 2021年第3期627-638,共12页
Increasing evidence indicates that aberrant expressions of some microRNAs are associated with cancer progression.However,the roles and biological mechanisms of miRNA-16-5p in human non-small cell lung cancer(NSCLC)are... Increasing evidence indicates that aberrant expressions of some microRNAs are associated with cancer progression.However,the roles and biological mechanisms of miRNA-16-5p in human non-small cell lung cancer(NSCLC)are not to be well studied.Here,we validated that the expression of miR-16-5p was decreased significantly in NSCLC samples and cell lines.The correlation between the clinicopathological features of NSCLC and the miR-16-5p expression showed that the expression of miR-16-5p in non-small cell lung cancer was linked with the advanced TNM stage,positive lymph node metastasis,with short overall survival(OS).Also,a negative correlation between miR-16-5p and Fermitin family member 2(FERMT2)was observed,implying there may be a potential link about their regulation.The hypothesis was further confirmed by in-silico analysis and dual-luciferase reporter assay.Moreover,we demonstrated that the transfections of miR-16-5p mimics could alter some biological characteristics of NSCLC cells remarkably accomplished by the expression variance of FERMT2 in vitro and in vivo assays.Summarily,this study demonstrated that miR-16-5p,as a tumor suppression factor in NSCLC by targeting FERMT2,could serve as one promising biomarker in the prediction for NSCLC patients. 展开更多
关键词 miR-16-5p non–small-cell lung cancer(NSCLC) Fermitin family member 2(FERMT2) APOPTOSIS INVASION Overall survival(OS)
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THE NAVIER-STOKES EQUATIONS WITH THE KINEMATIC AND VORTICITY BOUNDARY CONDITIONS ON NON-FLAT BOUNDARIES 被引量:1
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作者 Dan Osborne 《Acta Mathematica Scientia》 SCIE CSCD 2009年第4期919-948,共30页
We study the initial-boundary value problem of the Navier-Stokes equations for incompressible fluids in a general domain in R^n with compact and smooth boundary, subject to the kinematic and vorticity boundary conditi... We study the initial-boundary value problem of the Navier-Stokes equations for incompressible fluids in a general domain in R^n with compact and smooth boundary, subject to the kinematic and vorticity boundary conditions on the non-flat boundary. We observe that, under the nonhomogeneous boundary conditions, the pressure p can be still recovered by solving the Neumann problem for the Poisson equation. Then we establish the well-posedness of the unsteady Stokes equations and employ the solution to reduce our initial-boundary value problem into an initial-boundary value problem with absolute boundary conditions. Based on this, we first establish the well-posedness for an appropriate local linearized problem with the absolute boundary conditions and the initial condition (without the incompressibility condition), which establishes a velocity mapping. Then we develop apriori estimates for the velocity mapping, especially involving the Sobolev norm for the time-derivative of the mapping to deal with the complicated boundary conditions, which leads to the existence of the fixed point of the mapping and the existence of solutions to our initial-boundary value problem. Finally, we establish that, when the viscosity coefficient tends zero, the strong solutions of the initial-boundary value problem in R^n(n ≥ 3) with nonhomogeneous vorticity boundary condition converge in L^2 to the corresponding Euler equations satisfying the kinematic condition. 展开更多
关键词 Navier-Stokes equations incompressible vorticity boundary condition kinematic boundary condition absolute boundary condition non-flat boundary general domain Stokes operator Neumann problem Poisson equation VORTICITY strong solutions inviscid limit slip boundary condition
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Slip-Line Field Theory of Transversely Isotropic Body
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作者 阮怀宁 王维襄 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第4期335-345,共11页
A slip-line field theory of transversely isotropic body is proposed in the presentpaper in order to deal with problems in geology and geotechniques.The Goldenblat-Kopnov failure criterion is employed.The parameters in... A slip-line field theory of transversely isotropic body is proposed in the presentpaper in order to deal with problems in geology and geotechniques.The Goldenblat-Kopnov failure criterion is employed.The parameters in it are treated as functions of tempperature It is applicable to transverse isotropic media in non-uniform temperaturefield.The basic equtions of plastic deformation are developed while the associated ru-les of flow are derived.By means of characteristic line theory,slip-line slope formulasand laws of variation of stress and velocity along slip lines are obtained,The indenta-tion on semi-infinite media is calculated.The theory developed in this paper may be simplified into many classical theories such as Mises,Hill,and Coulomb ones,This complicated theory may be applied to geotechniques,geological structures,petroleumindustry,mining engineering,etc. 展开更多
关键词 slip-line field. transversely isotropic. non-uniform temperaturefield. failure criterion. limit equilibrium
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基于M-P法的抗滑桩支护边坡稳定性分析 被引量:40
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作者 梁冠亭 陈昌富 +1 位作者 朱剑锋 肖淑君 《岩土力学》 EI CAS CSCD 北大核心 2015年第2期451-456,469,共7页
为评价采用抗滑桩支护后的边坡稳定性,从设计和验算两个角度着手,基于Morgenstern-Price(M-P)法建立了抗滑桩支护边坡的分析模型,进而得到了抗滑桩下滑力和边坡安全系数的表达式;通过引入自适应遗传优化算法,建立边坡稳定性分析优化模型... 为评价采用抗滑桩支护后的边坡稳定性,从设计和验算两个角度着手,基于Morgenstern-Price(M-P)法建立了抗滑桩支护边坡的分析模型,进而得到了抗滑桩下滑力和边坡安全系数的表达式;通过引入自适应遗传优化算法,建立边坡稳定性分析优化模型,搜索采用抗滑桩支护边坡的非圆弧最危险滑动面;从确定安全系数求抗滑桩所受下滑力和确定抗滑桩抗力求边坡最小安全系数两种情况出发,探讨了抗滑桩位置对边坡稳定性的影响。结果表明:该方法可搜索出更加符合实际情况的边坡非圆弧最危险滑动面,并且能够得到抗滑桩的下滑力或边坡的最小安全系数,相同条件下抗滑桩应设置在边坡中部较为适合,才能最大发挥抗滑桩的加固作用。 展开更多
关键词 边坡 抗滑桩 稳定性 改进Morgenstern-Price法 非圆弧滑动面
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黄河泥沙非传统资源制备O′-SiAlON/SiC耐火材料 被引量:4
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作者 程科 徐斌 +2 位作者 徐利华 张菡 刘明 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2007年第A02期369-372,共4页
利用黄河泥沙合成O′-SiAlON/SiC复相耐火材料,着重将胶态成型工艺应用到制备过程中,即利用注浆成型工艺制备坯体,使坯体结构更均匀,同时促进最终产物的生成。探索了注浆成型中各工艺参数对坯体性能的影响,利用正交实验对注浆成型工艺... 利用黄河泥沙合成O′-SiAlON/SiC复相耐火材料,着重将胶态成型工艺应用到制备过程中,即利用注浆成型工艺制备坯体,使坯体结构更均匀,同时促进最终产物的生成。探索了注浆成型中各工艺参数对坯体性能的影响,利用正交实验对注浆成型工艺参数进行了优化设计,并得到最佳工艺参数,在此工艺条件下制备的坯体密度最高(1.86 g/cm^3)。最终在较低的烧结温度下制备出O′-SiAlON/SiC复相耐火材料,该材料具有相对较高的O′-SiAlON/SiC比及较少的杂质相含量。 展开更多
关键词 注浆成型 O'-SiAlON/SiC 黄河泥沙 非传统资源
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钢-混凝土组合梁非线性变形研究 被引量:6
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作者 谭文辉 李达 《工程力学》 EI CSCD 北大核心 2008年第A01期107-110,136,共5页
目前,对于钢-混凝土组合梁在荷载长期效应下挠度的研究,我国现行规范是通过降低弹性模量的方法来考虑荷载的长期效应,而没有充分考虑混凝土的收缩、徐变的影响。此外,组合梁交接面的滑移对长期挠度的影响也不可忽视。综合现有研究成果,... 目前,对于钢-混凝土组合梁在荷载长期效应下挠度的研究,我国现行规范是通过降低弹性模量的方法来考虑荷载的长期效应,而没有充分考虑混凝土的收缩、徐变的影响。此外,组合梁交接面的滑移对长期挠度的影响也不可忽视。综合现有研究成果,选取影响挠度的主要影响因素:混凝土的收缩、徐变和抗剪连接件的滑移进行考虑,推导出考虑混凝土的徐变、收缩和剪切件滑移的钢-混凝土组合梁长期挠度计算公式,并对一高层建筑中的两根典型组合梁进行了现场监测与分析。理论分析和实测结果表明:用现行规范中的计算方法计算出的组合梁的长期挠度值偏小,因此,对组合梁的设计和施工提出了一些建议。 展开更多
关键词 -混凝土组合梁 长期挠度 徐变 收缩 滑移
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钢-混凝土组合梁非线性分析概述 被引量:5
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作者 毛小勇 张耀春 《哈尔滨建筑大学学报》 北大核心 2001年第5期19-24,共6页
对钢-混凝土组合梁非线性分析过程中的关键问题进行了分析,这些问题主要包括:混凝土本构关系模型的选用;混凝土的开裂模式及开裂后性能;钢和混凝土之间连接滑移的处理方法等。阐述了分段杆单元法、分层法、平面应力法等常用分析模型及... 对钢-混凝土组合梁非线性分析过程中的关键问题进行了分析,这些问题主要包括:混凝土本构关系模型的选用;混凝土的开裂模式及开裂后性能;钢和混凝土之间连接滑移的处理方法等。阐述了分段杆单元法、分层法、平面应力法等常用分析模型及其优缺点。最后,给出了组合梁非线性分析数值实现方法的几点建议。 展开更多
关键词 组合梁 非线性分析 有限元 裂缝 数值方法 钢梁 钢筋混凝土
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