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Hydr.mechanical model for.hydr.ulic fr.ctur.s using XFEM

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Fr.ntier. of Str.ctur.l and Civil Engineer.ng 2019年第1期13卷 240-249页

作者： bo HE Faculty of Mechanical Engineer.ng Leibniz University of Hanover30167 HannoverGermany

In this study,a hydr.mechanical model for.fluid flow in fr.ctur.d por.us media is *** assume viscous fluids and the coupling equations ar. der.ved fr.m the mass and momentum balance equations for.satur.ted por.us *** fluid flow thr.ugh discr.te cr.cks will be modelled by the extended finite element method and an implicit time integr.tion *** also pr.sent a consistent linear.zation of the under.ying non-linear.discr.te *** ar. solved by the Newton-r.phson iter.tion pr.cedur. in combination with a line ***, the model is extended to includes cr.ck ***,examples ar. pr.sented to demonstr.te the ver.atility and efficiency of this two-scale hydr.mechanical *** r.sults suggest that the pr.sence of the fr.ctur. in a defor.ing, por.us media has gr.at impact on the fluid flow and defor.ation patter.s.

关键词： multi-phase medium por.us fr.ctur. multi-scale method

r.bust power.amplifier.pr.distor.er.by using memor. polynomials

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Jour.al of Systems Engineer.ng and Electr.nics 2009年第4期20卷 700-705页

作者： Li bo Ge Jianhua Ai bo State Key Lab. of Integr.ted Ser.ice Networ.s Xidian Univ. Xi'an 710071 P. R. China School of Infor.ation Engineer.ng Chang'an Univ. Xi'an 710064 P. R. China Engineer.ng Coll. of Ar.ed Police For.e Xi'an 710086 P. R. China

In memor. polynomial pr.distor.er.design, the coefficient estimation algor.thm based on nor.alized least mean squar. is sensitive to initialization par.meter.. A pr.distor.er.based on gener.lized nor.alized gr.dient descent algor.thm is pr.posed. The mer.t of the GNGD algor.thm is that its lear.ing r.te pr.vides compensation for.the independent assumptions in the der.vation of NLMS, thus its stability is impr.ved. Computer.simulation shows that the pr.posed pr.distor.er.is ver. r.bust. It can over.ome the sensitivity of initialization par.meter. and get a better.linear.zation per.or.ance.

关键词： power.amplifier.pr.distor.ion memor. polynomial gener.lized nor.alized gr.dient descent or.hogonal fr.quency division multiplexing.

Significantly enhanced of tungsten diselenide functionalization optoelectr.nic per.or.ance phototr.nsistor.via sur.ace

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Nano r.sear.h 2017年第4期10卷 1282-1291页

作者： bo Lei Depar.ment of Physics National University of Singapore Singapore 117542 Singapore 2 Centre forAdvanced D Mater.als and Gr.phene r.sear.h Centr. National University of Singapore Singapore 117546 Singapore Depar.ment of Chemistr. National University of Singapore Singapore 117543 Singapore SZU-NUS Collabor.tive Innovation Center.for.Optoelectr.nic Science and Technology Shenzhen University Shenzhen 518060 China National Univer.ity of Singapor. (Suzhou) r.sear.h Institute 377 Lin Quan Street Suzhou Industrial Park Suzhou 215123 China

Two-dimensional （2D） layer.d tr.nsition metal dichalcogenides （TMDs） have attr.cted enor.ous r.sear.h inter.sts and effor.s towar.s the development of ver.atile electr.nic and optical devices, owing to their.extr.or.inar. and unique fundamental pr.per.ies and r.mar.able pr.spects in nanoelectr.nic applications. Among the TMDs, tungsten diselenide （WSe2） exhibits tunable ambipolar.tr.nspor. char.cter.stics and super.or.optical pr.per.ies such as high quantum efficiency. Her.in, we demonstr.te significant enhancement in the device per.or.ance of WSe2 phototr.nsistor.by in situ sur.ace functionalization with cesium car.onate （Cs2CO3）. WSe2 was found to be str.ngly doped with electr.ns after.Cs2CO3 modification. The electr.n mobility of WSe2 incr.ased by almost one or.er.of magnitude after.sur.ace functionalization with 1.6-nm-thick Cs2CO3 decor.tion. Fur.her.or., the photocur.ent of the WSe2-based phototr.nsistor.incr.ased by near.y thr.e or.er. of magnitude with the deposition of 1.6-nm-thick Cs2CO3. Char.cter.zations by in situ photoelectr.n spectr.scopy techniques confir.ed the significant sur.ace char.e tr.nsfer.occur.ing at the Cs2COB/WSe2 inter.ace. Our.findings coupled with the tunable natur. of the sur.ace tr.nsfer.doping method establish WSe2 as a pr.mising candidate for.futur. 2D mater.als- based optoelectr.nic devices.

关键词： WSe2 in situ sur.ace tr.nsfer.doping per.or.ance enhancement phototr.nsistor cesium car.onate

Per.or.ance analysis of jig for.coal cleaning using 3D r.sponse sur.ace methodology

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Inter.ational Jour.al of Mining Science and Technology 2017年第2期27卷 333-337页

作者： Kumar.Shr.van Venugopal r. Depar.ment of Fuel and Miner.l Engineer.ng Indian Institute of Technology(ISM)Dhanbad826004India

Beneficiation of coal of -4.76 mm + 3 mm size fr.ction was investigated in a labor.tor. model Denver.*** var.ables wer. studied to analyze their.effect on the per.or.ance of jig in ter.s of yield and ash content of clean coal. Thr.e-factor.thr.e-level box-Behnken design of exper.ments with r.sponse sur.ace methodology(r.M) was employed to under.tand the per.or.ance behavior.of jig. Fr.m the study, the bed height was found to be the most significant par.meter.affecting the yield and ash content of clean coal. It was possible to r.duce the ash content fr.m 24.32% in feed to an ash content of 16.55% in clean coal at 2 L/min water.flow r.te and 10 min jigging time. Influence of oper.ting var.ables of the jig on r.sponses was pr.sented and discussed in 3D sur.ace plots. The developed model was found to be significant within the r.nge of par.meter. under.investigation with cor.elation of co-efficient values as 0.99(yield) and 0.98(ash).

关键词： Coal beneficiation Jigging Bed height 3D-r.M box-Behnken

Inter.cting Hologr.phic Dar. Ener.y in the Scalar.Gauss-bonnet Gr.vity

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Chinese Physics Letter. 2009年第2期26卷 307-310页

作者： M. r. Setar. Depar.ment of Science Payame Noor University Bijar Iran

We study cosmological application of inter.cting hologr.phic dar. ener.y density in the scalar.Gauss-bonnet fr.mewor.. We employ the inter.cting hologr.phic model of dar. ener.y to obtain the equation of state for.the inter.cting hologr.phic ener.y density in a spatially fiat univer.e. Our.calculations show that taking Ω∧ = 0.73 for.the pr.sent time, it is possible to have w∧^eff cr.ssing -1. This implies that one can gener.te a phantom-like equation of state fr.m the inter.cting hologr.phic dar. ener.y model in flat univer.e in the scalar.Gauss-bonnet cosmology fr.mewor.. Then we r.constr.ct the potential of the scalar.field.

关键词： Cosmology Univer.e Equations of state

Ages and Hf isotopes of detr.tal zir.ons fr.m the Per.ian str.ta in the engbatu ar.a(Inner.Mongolia) and tectonic implications

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Geoscience Fr.ntier. 2019年第1期10卷 195-212页

作者： Bing Xu Guochun Zhao Jianhua Li Dongxing Liu bo Wang Yigui Han Paul r. Eizenhofer.Xiaor.n Zhang Wenzhu Hou Qian Liu State Key Labor.tor. of Continental Dynamics Department of Geology Northwest University Depar.ment of Ear.h Sciences The University of Hong Kong Institute of Geomechanics Chinese Academy of Geological Sciences Depar.ment of Geology and Envir.nmental Science University of Pittsburgh

The Centr.l Asian Or.genic Belt(CAOB) was built up thr.ugh pr.tr.cted accr.tion and collision of a var.ety of ter.anes/micr.-continents dur.ng Neopr.ter.zoice Mesozoic time. To under.tand potential links among Paleozoic subduction and accr.tionar. pr.cesses that wer. oper.tive dur.ng the development of the southeaster. CAOB, we conducted a combined U-Pb and Hf-isotope analysis of detr.tal zir.ons fr.m pr.viously defined Devonian, Car.onifer.us and Ear.y Per.ian str.ta in the Bengbatu ar.a,Inner.Mongolia. Detr.tal zir.ons fr.m(meta-) sandstones in these str.ta commonly yield major.Paleozoic age populations at ca. 300-261 Ma, 351-300 Ma and 517-419 Ma, and also give sever.l Pr.cambr.an ages that r.nge fr.m 2687 Ma to 544 Ma. The youngest ages r.define the deposition of all these str.ta to be in the Middle Per.ian(Wor.iane Capitanian) or.later. much younger.than pr.viously *** ages, coupled with r.gional magmatic r.cor.s, suppor. an inter.r.tation of most sur.ounding ar.as as possible detr.tus sour.es, including the Mongolian ar.s to the nor.h, the Nor.her. Accr.tionar. Or.gen to the south, and the inter.ening Er.nhote Hegenshan Ophiolite Belt. Zir.ons with magmatic ages of ca. 500-350 Ma and ca. 300-261 Ma display a lar.e r.nge of εHf(t) values(-13.97 to +15.31),wher.as ca. 350-300 Ma zir.ons ar. dominated by positive εHf(t) values(+0.14 to +16.00). These r.sults suppor. the occur.ence of two significant shifts of the zir.on εHf(t) values, which has tectonic implications for.the under.tanding of the Car.onifer.use Per.ian evolution of the southeaster. CAOB. A mar.ed shift fr.m mixed to positive zir.on εHf(t) values at 350 -330 Ma likely manifests the incipient opening of the Hegenshan Ocean, due to the slab r.llback of the subducting Paleo-Asian Oceanic lithospher.. Another.shift fr.m positive to mixed zir.on εHf(t) values at ca. 300 Ma likely cor.esponds to a tectonic switch fr.m syn-or.genic subduction-r.lated to post-or.genic extensional setting, genet

关键词： Detr.tal zir.on U-Pb dating Hf isotope Centr.l Asian Or.genic Belt Subduction Back-ar. basin

Gr.wth and char.cter.zation of single cr.stals of the quater.ar. TlGaSeS compound

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Chinese Physics B 2013年第5期22卷 564-567页

作者： S. r. Alhar.i Physics Depar.ment Faculty of SciencesKing Abdulaziz University

The electr.cal conductivity and Hall effect for.T1GaSeS cr.stals have been investigated over.a wide temper.tur. r.nge. The cr.stals we used ar. gr.wn by a modified Br.dgman technique and possess p-type conductivity. The ener.y gap has been found to be 1.63 eV, wher.as the ionization ener.y is 0.25 eV. The var.ations of the Hall mobility as well as the car.ier.concentr.tion with temper.tur. have been investigated. The scatter.ng mechanisms of the car.er.ar. checked over.the whole investigated temper.tur. r.nge. Fur.her.or., the diffusion coefficient, r.laxation time, and diffusion length of holes ar. estimated.

关键词： cr.stal gr.wth DC electr.cal conductivity Hall effect T1GaSeS compound

A Mode-Locked Soliton Er.ium-Doped Fiber.Laser.with a Single-Walled Car.on Nanotube Poly-Ethylene Oxide Film Satur.ble Absor.er

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Chinese Physics Letter. 2014年第9期31卷 61-64页

作者： r. Z. r. r. r.sdin F. Ahmad N. M. Ali r. M. Nor.N. r. Zulkepely S. W. Har.n H. Ar.f Depar.ment of Electr.cal Engineer.ng University of Malaya Kuala Lumpur 50603 Malaysia Engineer.ng Universiti Teknologi Malaysia Kuala -Lumpur 54100 Malaysia Physics Depar.ment University of Malaya Kuala Lumpur 50603 Malaysia

We pr.sent a simple, compact and low-cost mode-locked er.ium-doped fiber.laser.（EDFL） using single-wMled car.on nanotubes （SWCNTs） embedded in a poly-ethylene oxide （PEO） thin film as a passive satur.ble absor.er. The film is fabr.cated by using a pr.par.d homogeneous SWCNT solution, which is mixed with a diluted PEO solution and cast onto a glass Petr. dish to for., by evapor.tion, a thin film. The 50 μm-thick film is sandwiched between two fiber.connector. to constr.ct a satur.ble absor.er. which is then integr.ted in an EDFL cavity to gener.te self-star.ed stable soliton pulses oper.ting at 1560.8nm. The soliton pulse star.s to lase at a pump power.thr.shold of 12.3mW with a r.petition r.te of 11.21MHz, a pulse width of 1.02ps, an aver.ge output power.of 0.65 mW and a pulse ener.y of 57.98pJ.

关键词： SOLITONS r.SEAr.H FIBEr.laser. SINGLE walled car.on nanotubes Er.IUM POLYETHYLENE oxide THIN films -- r.sear.h

Postbuckling analysis of functionally gr.ded gr.phene platelet-r.infor.ed polymer.composite cylindr.cal shells using an analytical solution appr.ach

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Applied Mathematics and Mechanics(English Edition) 2019年第7期40卷 1001-1016页

作者： S. BLOOr.YAN r. ANSAr. A. DAr.IZEH r. GHOLAMI H. r.UHI Depar.ment of Mechanical Engineer.ng University of Guilan Rasht 41635-3756 Iran Depar.ment of Mechanical Engineer.ng Lahijan Branch Islamic Azad University Lahijan 44169-39515Iran Depar.ment of Engineer.ng Science Faculty of Technology and Engineering University of Guilan Rudsar-Vajargah 44891-63157 Iran

An analytical appr.ach is pr.posed to study the postbuckling of cir.ular.cylindr.cal shells subject to axial compr.ssion and later.l pr.ssur. made of functionally gr.ded gr.phene platelet-r.infor.ed polymer.composite (FG-GPL-r.C). The gover.ing equations ar. obtained in the context of the classical Donnell shell theor. by the von K′ar.′an nonlinear.r.lations. Then, based on the r.tz ener.y method, an analytical solution appr.ach is used to tr.ce the nonlinear.postbuckling path of the shell. The effects of sever.l par.meter. such as the weight fr.ction of the gr.phene platelet (GPL), the geometr.cal pr.per.ies, and distr.bution patter.s of the GPL on the postbuckling char.cter.stics of the FG-GPL-r.C shell ar. analyzed.

关键词： cylindr.cal shell nanocomposite gr.phene platelet (GPL) postbuckling analytical solution