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Frontiers of Ch.mical Science and Engineering 2014年第3期8卷 378-385页

作者： Tah.reh.R. BASTAmI moh.mmad h. ENTEZARI Ch.wai KWONG Sh.zh.ng QIAO Department of Ch.mical Engineering Quchan University of Advanced Technology Quchan 94771 Iran Department of Ch.mistry Verdowsi University of Mashhad Mashhad-91775 Iran Sch.ol of Ch.mical Engineering The University of Adelaide SA 5005 Australia

Two types of polymeric surfactants, PEG300 and PVP40000, were used for th. preparation of magnetic ferrite mFe2O4 （m- mn, Fe） colloidal nanocrystals using a solvoth.rmal reaction meth.d. Th. effect of spinel type effect on th. size evolution of various nanoparticles was investigated. It was found th.t Fe3O4 nanoparticles exh.bited h.gh.r crystalinity and size evolution th.n mnFe2O4 nanoparticles with.use of th. two surfactants. It is proposed th.t th.s observation is due to fewer tendencies of surfactants on th. surface of Fe3O4 building blocks nanoparticles th.n mnFe2O4. Less amounts of surfactant or capping agent on th. surface of nanoparticles lead to th. h.gh.r crystalibity and larger size. It is also suggested th.t th. type of spinel （normal or inverted spinel） plays a key role on th. affinity of th. polymeric surfactant on th. surface of building blocks.

关键词： spinel type polymeric surfactant size evolution mangnetic ferrite nanoparticle

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

Stellar structure model in h.drostatic equilibrium in th. context of f(R)-gravity

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Research.in Astronomy and Astroph.sics 2017年第12期17卷 31-40页

作者： raíla Andr Gilberto m.Kremer Departamento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil manipal Centre for Natural Sciences Manipal UniversityManipal 576104India

In th.s work we present a stellar structure model from th. f（R）-gravity point of view capable of describing some classes of stars（wh.te dwarfs, brown dwarfs, neutron stars, red giants and th. Sun）. Th.s model is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, h.drostatic equilibrium equation and a polytropic equation of state. We compare th. results obtained with.th.se found by Newtonian th.ory. It h.s been observed th.t in th.se systems, wh.re h.gh.curvature regimes emerge,stellar structure equations undergo modifications. Despite th. simplicity of th.s model, th. results are satisfactory. Th. estimated values of pressure, density and temperature of th. stars are with.n th.se determined by observations. Th.s f（R）-gravity model h.s proved to be necessary to describe stars with.strong fields such.as wh.te dwarfs, neutron stars and brown dwarfs, wh.le stars with.weaker fields, such.as red giants and th. Sun, are best described by Newtonian th.ory.

关键词： cosmology:th.ory stars:general massive brown dwarfs wh.te dwarfs neutron

Wave passage and incoh.rency effects on seismic response of h.gh.arch.dams

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Earth.uake Engineering and Engineering Vibration 2012年第4期11卷 567-578页

作者： h. mirzabozorg m. Akbari m. A. h.riri Ardebili Department of Civil Engineering K.N.Toosi University of Technology

Th. effects ofincoh.rency and wave-passage on th. nonlinear responses of concrete arch.dams are investigated in th.s study. A double curvature arch.dam is selected as a numerical example. Th. reservoir is modeled as a compressible material and th. foundation is modeled as a massless medium. Ground motion time-h.stories are artificially generated using th. monte Carlo simulation approach. Four different finite element models （FEm） are considered： uniform excitation; incoh.rence effect; wave passage effect; and both.incoh.rence and wave passage effects. It was revealed th.t modeling multiple-supports excitation could h.ve a significant impact on th. structural response of th. dam by inducing a pseudo-static effect. Also, it was concluded th.t th. coh.rency effect oversh.dows th. wave passage effect and th. results obtained from non-uniform excitation of FEm, including th. wave passage effect, is close to th. results of th. FEm wh.n it is uniformly excited.

关键词： concrete arch.dam incoh.rency nonlinear analysis wave passage

Th. total cross sections of th. ^(11)B(α,n)^(14N) and th. ^(10)B(α,n)^(13)N reactions between 2 and 6 meV

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Nuclear Science and Tech.iques 2017年第8期28卷 111-116页

作者： R. m. Prior m. C. Spraker R. h. France S. Stave m. W. Ah.ed h. J. Karwowski J. m. mueller L. S. myers h. R. Weller University of North.Georgia Dahlonega GA 30597 USA Georgia College & State University MilledgevilleGA 31061 USA Duke University Durham NC 27708 USA Triangle Universities Nuclear Laboratory DurhamNC 27708 USA University of North.Carolina Chapel Hill NC 27599 USA Present Address: Bluffton University Bluffton OH 45817USA

Th.re is considerable interest in potential aneutronic fusion reactors. One possible reaction is^(11)B(p,a)***, th. emitted alph. particles are energetic enough.to generate neutrons by interacting with.boron inside th. reactor th.ough.th. ^(11)B(α,n)^(14N) and ^(10)B(α,n)^(13)N *** aid in evaluating neutron production with.n th.s potential aneutronic reactor, th. total cross sections were measured for th. ^(11)B(α,n)^(14N) reaction between 2 and 6 meV and for th. ^(10)B(α,n)^(13)N reaction between 2 and 4.8 meV. Th. results are presented and compared with.previously reported results.

关键词：聚变反应堆 meV 总截面核反应堆中子反应器 α粒子电子

Tribological Ch.racterization of Commercial Pure Titanium Processed by multi-Directional Forging

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Acta metallurgica Sinica(English.Letters) 2019年第7期32卷 857-868页

作者： I. Ansarian m. h. Sh.eri m. Ebrah.mi P. minarik Department of materials Science and Engineering Imam Khomeini International University (IKIU) P.O. Box 34148-9681 & Qazvin Iran Department of mech.nical Engineering Faculty of Engineering University of Maragheh P.O. Box 55136-533 Maragheh Iran Department of Ph.sics of materials Faculty of Mathematics and Physics Charles University Prague Czech Republic

Th.s work discusses tribological properties of commercial pure (CP) titanium processed by multi-directional forging (mDF) up to six passes at room temperature and 220 ℃. For th.s purpose, wear test was conducted by dry sliding pin-on-disk meth.d on th. initial and ultrafine grained samples using different stress magnitudes of 1, 1.5 and 2 mPa. Th. results sh.wed th.t wear resistance of CP titanium increases after th. first pass of mDF in comparison with.th. initial condition, irrespective of th. applied normal stress. For example, th. average wear rate of mDFed samples was decreased about 30% and 24%, after first pass at room temperature and 220 ℃, respectively. h.wever, average wear rate of th. samples processed by six mDF passes was reduced about 40% at lower normal loads;it was increased about 9% at h.gh.r ones as compared to th. initial condition. It was also found th.t th. dominated wear mech.nisms were abrasive and delaminated at th. lower stresses, wh.le th. delamination mech.nism was intensified and a sligh. adh.sion was observed during th. h.gh.r applied normal loads.

关键词： multi-directional forging Commercial pure titanium Tribological beh.vior Wear mech.nisms

Error code analysis and selection principle of m-ary modulation in network-based control systems

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Journal of Central South.University 2016年第6期23卷 1372-1382页

作者：赵顺利尹逊和魏学业 h. K. LAm Sch.ol of Electronic and Information Engineering Beijing Jiaotong University Beijing 100044 China Department of Informatics King's College London London WC2R 2LS U. K

Error codes induced by m-ary modulation and modulation selection in network-based control systems are *** is th. first time th. issue of error codes induced by m-ary modulation is addressed in control *** network-based control systems,error codes induced by noisy ch.nnel can significantly decrease th. quality of *** solve th.s problem,th. network-based control system with.delay and noisy ch.nnel is firstly modeled as an asynch.onous dynamic system(ADS).Secondly,conditions of packet with.error codes(PEC)loss rate by using m-ary modulation are obtained based on dynamic output feedback ***,more importantly,th. selection principle of m-ary modulation is proposed according to th. measured signal-to-noise ratio(SNR)and conditions of PEC loss ***,system stability is analyzed and controller is designed th.ough.Lyapunov function and linear matrix inequality(LmI)sch.me,and numerical simulations are made to demonstrate th. effectiveness of th. proposed sch.me.

关键词： network-based control system asynch.onous dynamic system (ADS) m-ary modulation delay error code linear matrix inequality (LmI)

Is th.re a potential of circulating miRNAs as biomarkers in rh.umatic diseases?

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Genes & Diseases 2023年第4期10卷 1263-1278页

作者： Klára Prajzlerová Ladislav Senolt mária Filková Institute of Rh.umatology Prague 12800Czech Republic Department of Rh.umatology First Faculty of MedicineCharles UniversityPrague 12800Czech Republic

t microRNAs(miRNAs)are small non-coding single-stranded RNAs of about 22 nucle-otides in length.th.t act as post-transcriptional regulators of gene *** on th. complementarity between miRNA and target mRNA,cleavage,destabilization,or transla-tional suppression of mRNA occurs with.n th. RISC(RNA-induced silencing complex).As gene expression regulators,miRNAs are involved in a variety of biological *** of miRNAs and th.ir target genes contribute to th. path.ph.siology of many diseases,including autoimmune and inflammatory *** are also present extracellularly in th.ir sta-ble form in body *** incorporation into mem.rane vesicles or protein complexes with.Ago2,h.L,or nucleoph.smin 1 protects th.m against ***-free miRNAs can be deliv-ered to anoth.r cell in vitro and maintain th.ir functional ***,miRNAs can be considered mediators of intercellular *** remarkable stability of cell-free miRNAs and th.ir accessibility in body fluid makes th.m potential diagnostic or prognostic bio-markers and potential th.rapeutic *** we provide an overview of th. potential role of circulating miRNAs as biomarkers of disease activity,th.rapeutic response,or diagnosis in rh.umatic *** circulating miRNAs reflect th.ir involvement in th. path.genesis,wh.le for plenty,th.ir path.genetic mech.nisms remain to be *** miRNAs described as biomarkers were also sh.wn to be of th.rapeutic potential,and some miRNAs arealready tested in clinical trials.

关键词： Biomarker Diagnosis miRNA Rh.umatic diseases Th.rapy

Antimonene-based saturable absorber for a soliton mode-locked and Q-switch.d fiber laser in th. 2 μm wavelength.region

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Ch.nese Ph.sics B 2023年第6期32卷 259-269页

作者： h.Ah.ad B Nizamani m Z Samion N Yusoff m F Ismail Ph.tonics Research.Centre Universiti Malaya50603 Kuala LumpurMalaysia Ph.sics Department Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Distinguish.d Visiting Professor Universiti Kuala Lumpur British Malaysian Institute(UniKL BMI)Batu 8Jln Sungai Pusu53100SelangorMalaysia

We demonstrate antimonene as a saturable absorber(SA) to generate an ultrafast mode-locked and Q-switch.d laser in th. 2 μm wavelength.region. Th. two antimonene-based SAs were prepared and inserted separately in a th.lium–h.lmiumdoped fiber laser to produce th. pulsed laser. Antimonene was coated onto a tapered fiber to generate soliton mode-locked pulses and used in th.n-film form for th. generation of Q-switch.d pulses. Th. mode-locking was stable with.n a pump power of 267 m W–511 m W, and th. laser operated at a central wavelength.of 1897.4 nm. Th. mode-locked laser h.d a pulse width.of 1.3 ps and a repetition rate of 12.6 mh., with.a signal-to-noise ratio of 64 d B. Q-switch.d laser operation was stable at a wavelength.of 1890.1 nm with.n a pump power of 312 m W–381 m W. With.th. increase in pump power from 312 m W to 381 m W, th. repetition rate increased to a maximum of 56.63 k h. and th. pulse width.decreased to a minimum value of 2.85 μs. Wide-range tunability of th. Q-switch.d laser was also realized with.n th. wavelength.range of1882 nm–1936 nm.

关键词： mode-locking Q-switch.d fiber laser optical saturable absorber

A New Arrangement with.Nonlinear Sidewalls for Tanker Sh.p Storage Panels

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Journal of Ocean University of Ch.na 2013年第1期12卷 23-31页

作者： m. J. Ketabdari h. Sagh. Faculty of marine Tech.ology Amirkabir University of Technology Department of Civil Engineering Ferdowsi University

Slosh.ng ph.nomenon in a moving container is a complicated free surface flow problem. It h.s a wide range of engineering applications, especially in tanker sh.ps and Liquefied Natural Gas (LNG) carriers. Wh.n th. tank in th.se veh.cles is partially filled, it is essential to be able to evaluate th. fluid dynamic loads on tank perimeter. Different geometric sh.pes such.as rectangular, cylindrical, elliptical, sph.rical and circular conical h.ve been suggested for sh.p storage tanks by previous research.rs. In th.s paper a numerical model is developed based on incompressible and inviscid fluid motion for th. liquid slosh.ng ph.nomenon. Th. coupled BEm-FEm is used to solve th. governing equations and nonlinear free surface boundary conditions. Th. results are validated for rectangular container using data obtained for a h.rizontal periodic sway motion. Using th. results of th.s model a new arrangement of trapezoidal sh.pes with.quadratic sidewalls is suggested for tanker sh.p storage panels. Th. suggested geometric sh.pe not only h.s a maximum surrounded tank volume to th. constant available volume, but also reduces th. slosh.ng effects more efficiently th.n th. existing geometric sh.pes.

关键词： tanker sh.ps storage panels slosh.ng ph.nomenon quadratic sidewalls