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bearing capacity and settlement of strip footing on geosynthetic reinforced clayey slopes

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Journal of Central South University 2012年第4期19卷 1116-1124页

作者： S.A.Naeini b.Khadem Rabe E.Mahmoodi Department of Civil Engineering Imam Khomeini International UniversityQazvin 16818-34149Iran

The effect of geosynthetic reinforcing on bearing capacity of a strip footing resting on georeinforced clayey slopes was *** results of a series of numerical study using finite element analyses on strip footing upon both reinforced and unreinforced clayey slopes were *** objectives of this work are to:1) determine the influence of reinforcement on the bearing-capacity of the strip footings adjacent slopes,2) suggest an optimum number of reinforcement and 3) survey the effect of friction angle in clayey soils reinforced by *** investigations were carried out by varying the edge distance of the footing from *** different numbers of geosynthetic layers were applied to obtaining the maximum bearing capacity and minimum *** achieve the third objective,two different friction angles were *** results show that the load?settlement behavior and ultimate bearing capacity of footing can be considerably improved by the inclusion of reinforcing *** using more than one layer reinforcement,the ultimate bearing capacity does not change *** is also shown that for both reinforced and unreinforced slopes,the bearing capacity increases with an increase in edge *** addition,as the soil friction angle is increased,the efficiency of reinforcing reduces.

关键词： geosynthetic reinforcing numerical analysis bearing capacity strip footing clayey slope friction angle

Infield superconducting properties of nano-sized Ag added Cu0.5Tl0.5ba2Ca2Cu3O10-δ

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Progress in Natural Science:Materials International 2017年第4期27卷 487-490页

作者： M.w.Rabbani Liaqat Ali M.Mumtaz Iftikhar Hussain Gul Materials Research Laboratory Department of Physics FBAS International Islamic University(IIU) Department of Material s Engineering(ME) Thermal Transport Laboratory(TTL)School of Chemical and Materials Engineering(SCME)National University of Science and Technology(NUST)

Infield superconducting properties of {(Ag)/CUTl-1223};(x = 0, 0.5,1.***.2.0 and 4.0 wt %) nanoparticlessuperconductor composites were investigated under different applied magnetic field up to H = 8 T. The increase in critical temperature {T(0)} and decrease in normal state resistivity(p) were observed with increasing contents of Ag nanoparticles in CuTl-1223 superconducting matrix. The value of T(K) remained almost unaffected by applying external magnetic field, but a decreasing trend in T(0) was observed by increasing the value of external applied magnetic field. The transition region below T(K) showed Arrhenius behavior due to thermally activated flow of magnetic vortices. Enhancement in flux flow activation energy(U) and suppression in transition width(ΔT) of CuTl-1223 phase with addition of Ag nanoparticles showed the improvement in flux pinning strength of superconductor.

关键词： Ag)_x/CuTl-1223 composites Activation energy Transition width Flux pinning Critical field

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静电雾化过程中粒径分布的预测

农业工程学报 2008年第12期24卷 89-92页

作者：张军 Michael w Reeks 集美大学机械工程学院能源与动力研究所厦门361021 纽卡斯尔大学机械与系统工程学院

运用信息熵方法对静电雾化过程中的雾滴尺寸分布进行了统计模拟,获得了预测粒径分布的统计模型。采用改进的Newton-Raphson算法对模型进行了数值计算,该模型可实现射流模式下的雾滴直径分布的预测。结果表明,射流模式下粒径分布较窄,最... 详细信息

运用信息熵方法对静电雾化过程中的雾滴尺寸分布进行了统计模拟,获得了预测粒径分布的统计模型。采用改进的Newton-Raphson算法对模型进行了数值计算,该模型可实现射流模式下的雾滴直径分布的预测。结果表明,射流模式下粒径分布较窄,最大粒径是最小粒径的2～3倍。通过与其他学者的试验数据比较表明,模型预测结果除了在较小流量情况下外,总体上与试验结果较为相符。该文的研究结果对静电雾化效果的优化及控制有一定的参考价值。

关键词：静电雾化信息熵数值计算雾滴直径分布

Structure of Ag/bi multilayers

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Chinese Science bulletin 1997年第16期42卷 1350-1353页

作者： Zhang, M Yu, w Liu, RP He, Dw wang, wK Chinese Acad Sci Inst Phys Beijing 100080 Peoples R China Chinese Acad Sci Int Ctr Mat Phys Shenyang 110015 Peoples R China

MULTILAYERS are often formed from two elemental layers deposited alternately. In recent years, multilayer thin films have been used increasingly in both basic research and technological fields because of their specific properties in electricity, light, magnetism and mechanics as well as their high interfacial density. In many applications, one has to consider the effects arising from microstructure. If the thickness of sublayers is very small (several nanometers),multilayers may exhibit a dimensional periodic structure (modulation structure) in the

关键词： Ag/bi multilayers interface.

Design concerns of room and pillar retreat panels

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International Journal of Mining Science and Technology 2017年第1期27卷 29-35页

作者： Klemetti Ted M. Sears Morgan M. Tulu Ihsan b. Mining Engineer Ground Control branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

why do some room and pillar retreat panels encounter abnormal conditions？ what factors deserve the most consideration during the planning and execution phases of mining and what can be done to mitigate those abnormal conditions when they are encountered7 To help answer these questions, and to determine some of the relevant factors influencing the conditions of room and pillar （R ＆ P） retreat min- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, multiple-seam interactions, geological conditions, and mining geometry. This paper details observations were made in four consecutive R ＆ P retreat panels and the data were collected from an instrumentation site during retreat mining. The pri- mary focus was on the differences observed among the four panels and within the panels themselves. The instrumentation study was initially planned to evaluate the interactions between primary and secondary support, but produced rather interesting results relating to the loading encountered under the current mining conditions. In addition to the obse^ation and ｜ll^trumentation, numerical modeling was per- formed to evaluate the stress condi~!ons. both the LaModel 3.0 and Rocscience Phase 2 programs were used to evaluate these four panels, The results of both models indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction mining in overlying seams when compared to the full overburden load. both models showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the observations and instrumentation studies performed at the mine. These efforts provided two overarching conclusions concerning R ＆ P retreat mine planning and execution. The first was that there are four areas that should not be overlooked during R ＆ P retreat mining： topographic relief, multiple^seaPa str

关键词： Room and pillar Retreat mining Deep coverSafety Multiple seam

Minimally Invasive Surgical Oncology 2011

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Surface and thermal effects on vibration of embedded alumina nanobeams based on novel Timoshenko beam model

2011年

作者： Ronald Matteotti Stanley w. Ashley

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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Applied Mathematics and Mechanics(English Edition) 2014年第7期35卷 875-886页

作者： b.AMIRIAN R.HOSSEINI-ARA H.MOOSAVI Department of Mechanical Engineering Isfahan University of TechnologyIsfahan 84156-83111 Iran Department of Mechanical Engineering Payame Noor University Tehran 19395-3697 Iran

This paper deals with the free vibration analysis of circular alumina （Al2O3） nanobeams in the presence of surface and thermal effects resting on a Pasternak foun- dation. The system of motion equations is derived using Hamilton＇s principle under the assumptions of the classical Timoshenko beam theory. The effects of the transverse shear deformation and rotary inertia are also considered within the framework of the mentioned theory. The separation of variables approach is employed to discretize the governing equa- tions which are then solved by an analytical method to obtain the natural frequencies of the alumina nanobeams. The results show that the surface effects lead to an increase in the natural frequency of nanobeams as compared with the classical Timoshenko beam model. In addition, for nanobeams with large diameters, the surface effects may increase the natural frequencies by increasing the thermal effects. Moreover, with regard to the Pasternak elastic foundation, the natural frequencies are increased slightly. The results of the present model are compared with the literature, showing that the present model can capture correctly the surface effects in thermal vibration of nanobeams.

关键词： surface effect thermal environment alumina nanobeam Pasternak foun-dation Timoshenko beam model

Grain growth in AZ31 alloy after uniaxial compression

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Transactions of Nonferrous Metals Society of China 2010年第12期20卷 2215-2222页

作者： S.AbDESSAMEUD H.AZZEDDINE b.ALILI D.bRADAI Laboratoire Faculty of PhysicsUniversity of Sciences and Technology Houari Boumediene(USTHB)BP32El-Alia Bab EzzouarAlgiers 16111Algeria

The grain growth morphology,kinetics and texture change after uniaxial compression at 430 ℃ of an extruded AZ31 alloy were *** samples were loaded following two routes insuring two initial textures of the samples with compression direction parallel and normal to the extrusion *** both initial textures,a stable grain size is attained upon isothermal annealing and the grain growth kinetics can be described by:dn= dRn+kt with an n value of around *** annealing texture with grown grains is a retained hot deformation texture without emerging or strengthening other *** grain growth is not observed for annealing time up to 10 000 h at 450℃.

关键词： AZ31 magnesium alloy uniaxial compression annealing grain growth texture

A Second Main Theorem on P^n for difference operator

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Science China Mathematics 2009年第12期52卷 2751-2758页

作者： wONG Pit-Mann LAw Hiu-Fai wONG Philip P.w. Department of Mathematics University of Notre Dame Department of Mathematics University of Hong Kong

The main result of this article is an extension of the Second Main Theorem,of Halburd and Korhonen,for meromorphic functions of finite *** result replaces the counting function of the ramification divisor Nramf(r)in the classical Second Main Theorem by the counting function of a finite difference divisor Npair(r).In this article,the Second Main Theorem of Halburd and Korhonen is extended to the case of holomorphic maps into Pn of finite order.

关键词： finite difference Second Main Theorem finite order ramification