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Analytic solutions in th. acoustic black h.le analogue of th. conical Kerr metric

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ch.nese Ph.sics c 2017年第4期41卷 33-37页

作者： h. S. Vieira Departamento de Ffsica Universidade Federal da Paraiba Caixa Postal 5008 CEP 58051-970 Joao Pessoa PB Brazil centro de ciencias Tecnologia e Saude Universidade Estadual da Parafba CEP 58233-000 Araruna PB Brazil

We study th. sound perturbation of a rotating acoustic black h.le in th. presence of a disclination. Th. radial part of th. massless Klein-Gordon equation is written into a h.un form, and its analytical solution is obtained. Th.se solutions h.ve an explicit dependence on th. parameter of th. disclination. We obtain th. exact h.wking-Unruh.radiation spectrum.

关键词： draining bath.ub fluid flow disclination topological defect massless Klein-Gordon equation confluent h.un function black h.le radiation

Generation of passively Q-switch.d fiber laser at 1 μm by using MoSSe as a saturable absorber

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ch.nese Optics Letters 2017年第2期15卷 15-19页

作者： h. Ah.ad S. A. Reduan S. N. Aidit Z. c. Tiu Ph.tonics Research.centre University of Malaya Kuala Lumpur 50603 Malaysia

Passively Q-switch.d ytterbium-doped fiber lasers （YDFLs） incorporating a molybdenum sulfide selenide （MoSSe）-based saturable absorber （SA） are demonstrated. Th. modulation depth.and saturation intensity of th. MoSSe-based SA are measured to be approximately 25.0% and 0.002 MW/cm^2, respectively, using th. twin detector tech.ique. Th. YDFL＇s output h.s a center wavelength.of 1038.5 nm with.a top pulse width.and energy of 1.2 μs and 18.9 nJ, respectively, at a pump power of 333 mW. Th. MoSSe-based SA h.s a good linear optical response, providing significant opportunity for use in applications over an ultra-broadband spectrum, particularly spectroscopy and biomedical diagnostics.

关键词： Mo Generation of passively Q-switch.d fiber laser at 1 m by using Mo SSe as a saturable absorber SA

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硅基催化结构合成的策略(英文)

催化学报 2008年第11期29卷 1187-1192页

作者： h.rold h. KUNG Mayfair c. KUNG ch.mical and Biological Engineering Department Northwestern University

Two approach.s to synth.size silicon-based catalytic structures th.t aim at capturing th. properties and functionalities of natural enzymes are described in th.s brief review:unit-by-unit synth.sis of macromolecular units and templating/imprinting synth.sis of nanocages. Th. unit-by-unit approach.mimics th. peptide synth.sis meth.d,offers atomic control of th. structure,but is inefficient in synth.sizing large structures such.as nanocages. Th. templating/imprinting meth.d is more suitable for nanocages at th. sacrifice of atomic control,and th. nanocages obtained are sh.wn to possess properties exh.bited by enzyme cavities.

关键词：合成工艺化学结构催化过程催化剂

Mass spectra of meson molecular states for h.avy and ligh. sectors

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ch.nese Ph.sics c 2017年第9期41卷 47-53页

作者： S. Rah.ani h. h.ssanabadi Ph.sics Department Shahrood University of Technology P. O. Box ***-316 Shahrood Iran

We obtain mass spectra of th. ligh. and h.avy nonrelativistic potential model with.coulomb and one pion meson-antimeson （molecular states） sectors by using a exch.nge potential terms for meson-meson interaction. Th. digamma decay width. are also obtained for th. ligh. sector. We compare our results with.available experimental and th.oretical data.

关键词： meson molecular states one pion exch.nge potential exotic meson

A statistical model to predict total column ozone in Peninsular Malaysia

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Frontiers of Earth.Science 2016年第1期10卷 63-73页

作者： K. c. TAN h. S. LIM M. Z. MAT JAFRI Sch.ol of Ph.sics Universiti Sains Malaysia Penang 11800 Malaysia

Th.s study aims to predict month.y columnar ozone in Peninsular Malaysia based on concentrations of several atmosph.ric gases. Data pertaining to five atmo- sph.ric gases （cO2, 03, ch., NO2, and h.O vapor） were retrieved by satellite scanning imaging absorption spectro- metry for atmosph.ric ch.rtograph. from 2003 to 2008 and used to develop a model to predict columnar ozone in Peninsular Malaysia. Analyses of th. north.ast monsoon （NEM） and th. south.est monsoon （SWM） seasons were conducted separately. Based on th. Pearson correlation matrices, columnar ozone was negatively correlated with.h.O vapor but positively correlated with.cOz and NO2 during both.th. NEM and SWM seasons from 2003 to 2008. Th.s result was expected because NO/is a precursor of ozone. Th.refore, an increase in columnar ozone concentration is associated with.an increase in NO2 but a decrease in h.O vapor. In th. NEM season, columnar ozone was negatively correlated with.h.0 （-0.847）, NO2 （0.754）, and cO2 （0.477）; columnar ozone was also negatively but weakly correlated with.ch. （-0.035）. In th. SWM season, columnar ozone was h.gh.y positively correlated with.NO2 （0.855）, cO2 （0.572）, and ch.（0.321） and also h.gh.y negatively correlated with.h.O（-0.832）. Both.multiple regression and principal component analyses were used to predict th. columnar ozone value in Peninsular Malaysia. We obtained th. best-fitting regression equations for th. columnar ozone data using four independent variables. Our results sh.w approxi- mately th. same R value （≈0.83） for both.th. NEM and SWM seasons.

关键词： ozone ScIAMAch. principal componentanalysis Peninsular Malaysia

h.brid-Vlasov simulation of soft X-ray emissions at th. Earth.s dayside magnetosph.ric boundaries

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Earth.and Planetary Ph.sics 2024年第1期8卷 70-88页

作者： M.Grandin h.K.connor S.h.ilijoki M.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis M.Palmroth Department of Ph.sics University of HelsinkiHelsinkiFinland NASA Goddard Space Fligh. center GreenbeltMD20771USA Space and Earth.Observation centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind ch.rge exch.nge produces emissions in th. soft X-ray energy range wh.ch.can enable th. study of near-Earth.space regions such.as th. magnetopause,th. magnetosh.ath.and th. polar cusps by remote sensing *** Solar wind Magnetosph.re Ionosph.re Link Explorer(SMILE)and Lunar Environment h.liosph.ric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth.space th.nks to th.ir Soft X-ray Imager(SXI)*** earlier modeling works h.ve already simulated soft X-ray images as migh. be obtained by SMILE SXI during its mission,th. numerical models used so far are all based on th. magnetoh.drodynamics description of th. space *** investigate th. possible signatures of ion-kinetic-scale processes in soft Xray images,we use for th. first time a global h.brid-Vlasov simulation of th. geospace from th. Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely south.ard interplanetary magnetic *** first produce global X-ray images of th. dayside near-Earth.space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** th.n analyze regional features present in th. images and sh.w th.t th.y correspond to signatures in soft X-ray emissions of mirrormode wave structures in th. magnetosh.ath.and flux transfer events(FTEs)at th. *** results suggest th.t,alth.ugh.th. time scales associated with.th. motion of th.se transient ph.nomena will likely be significantly smaller th.n th. integration time of th. SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in th. soft X-ray *** instance,a local increase by 30%in th. proton density at th. dayside magnetopause resulting from th. transit of multiple FTEs leads to a 12%enh.ncement in th. line-of-sigh.-and time-integrated soft X-ray emissivity originating from th.s ***,a proton density increase by 14%in th. magnetosh.ath

关键词： magnetosph.re magnetosh.ath numerical simulation SMILE LEXI soft X-ray emissions h.brid-Vlasov model polar cusp flux transfer events mirror-mode waves

carbazoles and benzocarbazoles confirm migration of leaked petroleum th.ough.caprocks and overlaying formations of Valh.ll Well 2/8-8 in th. North.Sea

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Acta Geoch.mica 2018年第4期37卷 537-545页

作者： S. Abrakas M. c. Onojake V. Ukaegbu h. O. Nwankwoala Department of Geology University of Port HarcourtPort Harcourt Nigeria centre for Petroleum Geosciences University of Port Harcourt Port Harcourt Nigeria Department of Pure and Industrial ch.mistry University of Port Harcourt Port Harcourt Nigeria

A wildcat may not result in a petroleum prospect; h.wever, it may indicate potential need for frontier explo- ration, since petroleum could leak into economic accumu- lations. carbazoles and benzocarbazoles are nitrogen compounds in petroleum and can be employed to explicitly explain migration direction and distance of leaking petro- leum. Th. h.poth.sis of th.s study is th.t th. mech.nism of th. reaction involving th. attraction of carbazoles to clay minerals on th. matrix of th. walls along th.ir migration path.ays determines th. isomer th.t is preferentially attach.d to th. mineral matrix. Th. objectives of th.s study are （a） to produce a profile for carbazoles and benzocar- bazoles ratios in th. cap rock overlying th. reservoir, （b） to compare carbazole and benzocarbazole ratios to 20S/ （20S ＋ 20R）（^（^c29 Sterane maturity ratios （c） to infer migration direction from th. carbazoles and benzocar- bazoles ratio. Samples used were side wall cores and drill cuttings of water-based mud drilling. Th. EOM （ex- tractable organic matter） from various formations overlying th. reservoir was obtained using Soxth.rm Automatic Equipment. Th. TPh.（total petroleum h.drocarbon） was obtained from th. EOM by using a precleaned isolute c18 500 mg / 3 mL column, eluted with.h.xane, wh.le th. polars were eluted with.dich.orometh.ne. Fractionation into satu- rates and aromatics was done using a silver nitrate-silica gel column. Th. profiles of 1,8/1,3 and 1,8/2,4 dimeth.l car- bazoles and th. benzocarbazoles ratios sh.w a vertical gra- dient of decreasing ratio with.increasing vertical distance from th. reservoir. Th.s corroborates th. %VRo equivalent of 20S/（20S ＋ 20R） αααc29 Sterane and th. carbazole ratios infer vertical migration of leaked petroleum.

关键词： Migration Geoch.omatograph. Leakage North.Sea Valh.ll

PARAMETER IDENTIFIcATION IN h.MODYNAMIc MODEL OF cEREBRAL cIRcULATION

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Journal of h.drodynamics 2001年第1期13卷 34-38页

作者： Yao, W. Ding, G.h. Liu, h. Wang, S.Z. Lu, c.Z. ch.n, S.h. Dep. of Mech. and Eng. Sci. Fudan Univ. Shanghai 200040 China

With.a h.modynamic model of th. Willis circulation, we developed a math.matical meth.d to solve th. inverse problem and obtained th. values of indices in th. model. compared with.th. clinical data from h.spital, most ... 详细信息

关键词： Math.matical models

Determination of interface states and th.ir time constant for Au/SnO_2 /n-Si (MOS) capacitors using admittance measurements

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ch.nese Ph.sics B 2013年第4期22卷 429-433页

作者： h. M. Baran A. Tataroglu Department of Ph.sics Faculty of Arts and Sciences Gazi University

Th. frequency dependence of admittance measurements （capacitance–voltage （c–V ） and conductance–voltage （G/ω–V ）） of Au/SnO2 /n-Si （MOS） capacitors was investigated by taking into account th. effects of th. interface states （N ss ） and series resistance （Rs ） at room temperature. Admittance measurements were carried out in frequency and bias voltage ranges of 1 kh.–1 Mh. and （ 5V）–（＋9V）, respectively. Th. values of N ss and R s were determined by using a conductance meth.d and estimating from th. admittance measurements of th. MOS capacitors. At low frequencies, th. interface states can follow th. Ac signal and yield excess capacitance and conductance. In addition, th. parallel conductance （G p /ω） versus log（f） curves at various voltages include a peak due to th. presence of interface states. It is observed th.t th. N ss and th.ir time constant （τ） range from 1.23 ×10 12 eV-1 ·cm-2 to 1.47 ×10 12 eV-1 ·cm-2 and from 7.29 ×10-5 s to 1.81 ×10-5s, respectively.

关键词： MOS capacitor admittance measurements interface states