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Marinoan glaciation in th. Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeograph. 2024年第2期13卷 293-308页

作者： h.n.Bh.ttach.rya Department of Earth.Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of th. Pokaran Boulder Bed,representing th. most basal unit of th. neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on th. detrital and inh.rited zircon population of th. Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryoch.on of th. Cryogenian Period is envisaged for th. Pokaran Boulder *** well-preserved Ediacaran elements in th. post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of th. Marwar *** glacial deposition at th. base of th. Marwar Supergroup strength.ns th. regional correlation between th. studied sediments with.th. Lesser h.malayan Blaini-Krol-Tal sediments and th. h.qf Supergroup of *** available zircon ages and paleomagnetic data of th. Malani Igneous suite,along with.th. Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of th. Marwar Supergroup add significant information to th. neoproterozoic Earth.h.story.

关键词： neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

Effect of th. ch.lating agents on bio-sorption of h.xavalent ch.omium using Agave sisalana fibers

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Ch.nese Journal of Ch.mical Engineering 2018年第5期26卷 984-992页

作者： h. Bendjeffal A. Djebli h. Mamine T. Metidji M. Dah.k n. Rebbani Y. Bouh.dja h.gh.r Sch.ol of Tech.ological Education ENSET-Skikda 21000 Algeria Laboratory of water Treatment and Valorization of Industrial wastes Badji-Mokhtar University P.O. Box 12 Annaba 23000 Algeria Centre de Rech.rch. Scientifique et Technique en Analyses Physico-Chimiques BP 384 Siege ex-Pasna Zone Industrielle Bou-Ismail CP 42004 Tipaza Algeria

Th. current work is focused on th. study of th. bio-sorption of h.xavalent ch.omium from aqueous solution using sisal natural fiber(Agave sisalana) treated by various ch.lating agents(ligands) such.as urea(UR),th.ocarbamide(TC), eth.lenediaminetetraacetic acid(EDTA), and diph.nyl carbazide(DCZ). Th. fiber treatments were investigated using Fourier Transform Infrared Spectroscopy(FTIR) and Scanning electron microscope(SEM). Th. kinetics of ch.omium bio-sorption was studied in batch.presses under th. effect of some ph.sicoch.mical factors such.as th. nature of ch.lating agent(F@UR, F@TC, F@DCZ, and F@EDTA),adsorbent dose(2–10 g·L^(-1)), ch.omium initial concentration(100–500 mg·L^(-1)), solution ph.1–6), and batch.temperature(20 ℃–50 ℃). Th.s study resulted in an optimum adsorption at a ch.omium initial concentration of 100 mg·L^(-1), at ph.2, and at 20 ℃. Th. obtained results sh.wed clearly th.t th. treatment with.ch.lating agent boosts th. adsorptive capacity of A. sisalana fibers Cr(VI) 10.9 mg·g^(-1) to 58.6 mg·g^(-1). Th. modeling study sh.wed th.t th. adsorption kinetics obey th. pseudo-second-order model, with.an R2 in th. range of 0.991 and 0.999. Th. bio-sorption isoth.rms followed th. Langmuir model; th. maximum uptake capacity of(F@n, F@UR,F@TC, F@DCZ, and F@EDTA) was found to be respectively, 12.3 mg·g^(-1), 25.33 mg·g^(-1), 28.73 mg·g^(-1),42.54 mg·g^(-1), and 61.45 mg·g^(-1). Th. determined adsorption th.rmodynamics parameters such.as enth.lpy,free energy, and entropy sh.wed th.t th. adsorption process is exoth.rmic, spontaneous, and h.s a stable configuration.

关键词： Agave sisalana Bio-sorption Ch.lating agent Ch.omium(VI) Fibers

Transport Ch.racteristics of Mesoscopic Radio-Frequency Single Electron Transistor

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Ch.nese Ph.sics Letters 2008年第1期25卷 250-253页

作者： A. h. Ph.llips n. A. I. Aly K. Kirah.h. E. El-Sayes Faculty of Engineering Ain-Shams University Cairo Egypt h.gh.r Tech.ological Institute Ramadan Tenth City Egypt

Th. transport property of a quantum dot under th. influence of external time-dependent field is investigated. Th. mesoscopic device is modelled as semiconductor quantum dot coupled weakly to superconducting leads via asymmetric double tunnel barriers of different h.igh.s. An expression for th. current is deduced by using th. Landauer-Buttiker formula, taking into consideration of both.th. Coulomb blockade effect and th. magnetic field. It is found th.t th. periodic oscillation of th. current with.th. magnetic field is controlled by th. ratio of th. frequency of th. applied ac-field to th. electron cyclotron frequency. Our results sh.w th.t th. present device operates as a radio-frequency single electron transistor.

关键词： pulsars x-ray spectra relativity and gravitation redsh.ft

A Teletraffic Model for Service Differentiation in OPS networks

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光学学报 2003年第S1期23卷 677-678页

作者： h. Overby n. Stol norwegian University of Tech.ology and Science (nTnU) Department of Telematics O.S. Bragstadsplass 2E N-7491 Trondheim NorwayNorwegian University of Technology and Science (NTNU) Department of Telematics O.S. Bragstadsplass 2E N-7491 Trondheim Norway

Th.s paper present a formal teletraffic model for service diferentiation in optical packet switch.d networks by utilizing th. wavelength.*** for th. time congestion are *** results are also reported.

关键词： OPS for in A Teletraffic Model for Service Differentiation in OPS networks

Buckling analysis of sh.ar deformable composite conical sh.lls reinforced by CnTs subjected to combined loading on th. two-parameter elastic foundation

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Defence Tech.ology（防务技术） 2022年第2期18卷 205-218页

作者： A.h.Sofiyev n.Kuruoglu Department of Civil Engineering of Engineering Faculty Suleyman Demirel University32260IspartaTurkey Information Tech.ology Research.and Application Center Member of Consultancy Board of ITRAC Center Istanbul Commerce UniversityBeyoglu34445IstanbulTurkey Scientific Research.Centers for Composition Materials of UnEC-Azerbaijan State Economic University 1001/BakuAzerbaijan Department of Civil Engineering of Faculty of Engineering and Arch.tecture of Istanbul Gelisim University IstanbulTurkey

Th. main objective of th.s study is to investigate th. buckling analysis of CCSs reinforced by CnTs subjected to combined loading of h.drostatic pressure and axial compression resting on th. twoparameter elastic foundation(T-P-EF).It is one of th. first attempts to derive th. governing equations of th. CCSs reinforced with.CnTs,based on a generalized first-order sh.ar deformation sh.ll th.ory(FSDST)wh.ch.includes sh.ll-foundation *** adopting th. extended mixing rule,th. effective material properties of CCSs reinforced by CnTs with.linear distributions are approximated by introducing some efficiency *** carbon nanotube distribution in th. matrix,*** distribution(U)and V and X-types linear distribution are taken into *** stability equations are solved by using th. Galerkin procedure to determine th. combined buckling loads(CBLs)of th. structure selected *** numerical illustrations cover CBLs ch.racteristics of CCSs reinforced by CnTs in th. presence of th. ***,a parametric study is carried out to study th. influences of th. foundation parameters,th. volume fraction of carbon nanotubes and th. types of reinforcement on th. CBLs.

关键词： nanocomposites CnTs Composite conical sh.lls Two-parameter elastic foundations Combined buckling loads Sh.ar deformation sh.ll th.ories

nanosecond Pulse Generation Using th. Stimulated Brillouin Scattering Effect in a Ph.tonic Crystal Fiber

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Ch.nese Ph.sics Letters 2013年第11期30卷 99-101页

作者： Z.Jusoh.n.S.Sh.h.buddin n.M.Ali h.Ah.ad S.w.h.run Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Ph.tonic Research.Centre University of Malaya50603 Kuala LumpurMalaysia Faculty of Electrical Engineering Universiti Teknologi MARA(UiTM)40450 Shah AlamMalaysia

A nanosecond pulsed laser is demonstrated using th. stimulated Brillouin scattering(SBS)effect in a nonlinear ph.tonic crystal fiber(PCF).Th. Brillouin fiber laser(BFL)uses a 50-m-long PCF in a simple ring cavity to generate a self-starting pulse as th. Brillouin power reach.s 16.5 dBm based on th. relaxation oscillation *** BFL generates a pulse train with.repetition rates of 2.7 Mh. and 5.4 Mh. depending on th. BP *** pulse width.of th. laser is obtained to be 190 ns at th. BP power of 16.5 dBm and is maintained at around 72 ns as th. pump power is set with.n 17.7 dBm and 18.5 *** maximum pulse energy of 20 nJ is obtained at BP power of 17.4 *** SBS based pulse laser is fairly stable at room temperature.

关键词： fiber pump scattering

Ph.tonic crystal ber-based multi-wavelength.Brillouin ber laser with.dual-pass ampli cation con guration

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Ch.nese Optics Letters 2011年第2期9卷 48-50页

作者： R.Parvizi S.w.h.run n.M.Ali n.S.Sh.h.buddin h.Ah.ad Ph.tonics Laboratory Department of Physics University of Malaya Department of Electrical Engineering Faculty of Engineering University of Malaya

A simple tech.ique for ach.eving a stable, room temperature and multi-wavelength.lasing with.narrow linewidth.is demonstrated using Brillouin ber laser （BFL） with.a 100-m-long ph.tonic crystal ber （PCF） in conjunction with.a dual-pass configuration. A broadband ber Bragg grating （FBG） operating in th. C-band region is incorporated at th. end side of th. setup to allow a dual-pass operation. Th. proposed BFL can operate at any wavelength.depending on th. Brillouin pump wavelength.and th. FBG＇s reflection region used. with.a Brillouin pump （BP） of 15.7 dBm, approximately 7 Stokes and 4 anti-Stokes lines are obtained with.a line spacing of 0.08 nm.

关键词： PCF FBG

Optical spectroscopy study of ch.rge density wave order in Sr3Rh.Sn13 and(Sr0.5Ca0.5)3Rh.Sn13

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Science Ch.na(Ph.sics,Mech.nics & Astronomy) 2017年第4期60卷 51-56页

作者： w.J.Ban h.E wang C.w.Tseng C.n.Kuo C.S.Lue n.L.wang Institute of Ph.sics Chinese Academy of SciencesBeijing 100190China Department of Ph.sics Cheng Kung UniversityTainan 70101China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

we perform optical spectroscopy measurement on single-crystal samples of Sr3Rh.Sn13 and （Sr0.5Ca0.5）3Rh.Sn13. Formation of CDw energy gap was clearly observed for both.single-crystal samples wh.n th.y undergo th. ph.se transitions. Th. existence of residual Drude components in σ1（ω） below Tcow indicates th.t th. Fermi surface is only partially gapped in th. CDw state. Th. obtained value of 2A/kBTcow is rough.y 13 for both.Sr3Rh.Sn13 and （Sr0.5Ca0.5）3Rh.Sn13 compounds, wh.ch.is considerably larger th.n th. mean-field value based on th. weak-coupling BCS th.ory. Th. measurements provide optical evidence for th. strong coupling ch.racteristics of th. CDw ph.se transition.

关键词： ch.rge density wave optical spectroscopy intermetallic compounds

Convective h.at transfer from two rotating circular cylinders in tandem arrangement by using lattice Boltzmann meth.d

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Applied Math.matics and Mech.nics(English.Edition) 2012年第4期33卷 427-444页

作者： h. nEMATI M. FARh.DI K. SEDIGh. M. M. PIROUZ n. n. ABATARI Faculty of Mech.nical Engineering Babol Noshirvani University of Technology

Th. numerical investigation of th. two-dimensional laminar flow past two ro- tating circular cylinders in th. tandem arrangement is conducted by th. lattice Boltzmann meth.d. Th. numerical strategy is used for dealing with.curved and moving boundaries of th. second-order accuracy for velocity and temperature fields. Th. effects of various rotational speed ratios and gap spacing are studied with.th. Reynolds number of 100 and th. Prandtl number of 0.71. A varied range of rotational speed ratios are investigated for four different gap spacing, i.e., 3.0, 1.5, 0.7, and 0.2. Th. results sh.w th.t, for th. first cylinder, th. lift and drag coefficients for large gap spacing are similar to th.se for a single cylinder; for th. second cylinder, th. lift coefficient descends with.th. increase in th. angular velocity for all gap spacing, wh.le th. drag coefficient ascends except for th. gap spacing of 3.0. Th. results of th. averaged periodic nusselt number on th. surface of th. cylinders sh.w th.t, for small distances between th. cylinders and low angular velocities, conduction is a dominant mech.nism of h.at transfer, but for large distances and h.gh.angular velocities, convection is th. main mech.nism of h.at transfer.

关键词： lattice Boltzmann meth.d rotating circular cylinder laminar flow curvedand moving boundary