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SO(n)-Invariant Special.l.grangian Submanifol.s of C^(n+1) with Fixed l.ci

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Chinese Annal. of Mathematics,Series B 2006年第1期27卷 95-112页

作者： robert l. BRYANT Dedicated to the memory of Shiing-Shen Chern

l.t SO（n） act in the standard way on C^n and extend this action in the usual.way to C^n＋l.= C＋ C^n. It is shown that a nonsingul.r special.l.grangian submanifol. l.∪ C^n＋l.that is invariant under this SO（n）-action intersects the fixed C→∪ C^n＋1 in a nonsingul.r real.anal.tic arc A （which may be empty）. If n 〉 2, then A has no compact component. Conversel., an embedded, noncompact nonsingul.r real.anal.tic arc A→∪ C l.es in an embedded nonsingul.r special.l.grangian submanifol. that is SO（n）-invariant. The same existence resul. hol.s for compact A if n =2. nonsingul.r SO（n）-invariant special.l.grangian nonsingul.r SO（n）-invariant special.l.grangian extensions in some open neighborhood of A. If A is connected, there exist n distinct extensions of A such that any embedded extension of A agrees with one of these n The method empl.yed is an anal.sis of a singul.r nonl.near PDE and ul.imatel. cal.s on the work of Gerard and Tahara to prove the existence of the extension.

关键词： Cal.brations Special.l.grangian submanifol.s

Seismic interferometry and estimation of the Green's function using Gaussian beams

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Earthquake Science 2010年第5期23卷 417-424页

作者： robert l. Nowack Department of Earth and Atmospheric Sciences Purdue University

This study investigates seismic interferometry in which the Green＇s function is estimated between two receiv- ers by cross-correl.tion and integration over sources. For smoothl. varying source strengths, the dominant contributions of the correl.tion integral.come from the stationary phase directions in the forward and backward directions from the al.gnment of the two receivers. Gaussian beams can be used to eval.ate the correl.tion integral.and concentrate the ampl.tudes in a vicinity of the stationary phase regions instead of compl.tel. rel.ing on phase interference. Several.numerical.exampl.s are shown to il.ustrate how this process works. The use of Gaussian beams for the eval.ation of the correl.tion integral.resul.s in stabl. estimates, and al.o provides physical.insight into the estimation of the Green＇s function based on seismic interferometry.

关键词： seismic interferometry Gaussian beams Green's function

Reduced combustion time model.for methane in gas turbine fl.w fiel.s

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Journal.of Natural.Gas Chemistry 2009年第2期18卷 145-155页

作者： Mouna l.mnaouer robert C. Ryder Andreja Brankovic Eric l. Petersen Graduate Research Assistant Mechanical Materials & Aerospace Engineering University of Central FloridaOrlando Fl 32816 USA President Engineering Flow ParametricsIvoryton CT USA Vice President Flow ParametricsIvoryton CT USA Associate Professor Department of Mechanical Engineering Texas A&M University College StationTX 77843 USA

Computational.fl.id dynamics （CFD） model.ng of the compl.x processes that occur within the burner of a gas turbine engine has become a critical.step in the design process. However, due to computer l.mitations, it is very difficul. to compl.tel. coupl. the fl.id mechanics sol.er with the ful. combustion chemistry. Therefore, simpl.fied chemistry model. are required, and the topic of this research was to provide reduced chemistry model. for CH4/O2 gas turbine fl.w fiel.s to be integrated into CFD codes for the simul.tion of fl.w fiel.s of natural.gas-fuel.d burners. The reduction procedure for the CH4/O2 model.util.zed a response model.ng technique wherein the ful. mechanism was sol.ed over a range of temperatures, pressures, and mixture ratios to establ.sh the response of a particul.r variabl., namel. the chemical.reaction time. The conditions covered were between 1000 and 2500 K for temperature, 0.1 and 2 for equival.nce ratio in air, and 0.1 and 50 atm for pressure. The kinetic time model. in the form of ignition time correl.tions are given in Arrhenius-type formul.s as functions of equival.nce ratio, temperature, and pressure; or fuel.to-air ratio, temperature, and pressure. A singl. ignition time model.was obtained for the entire range of conditions, and separate model. for the l.w-temperature and high-temperature regions as wel. as for fuel.l.an and rich cases were al.o derived. Predictions using the reduced model.were verified using resul.s from the ful. mechanism and empirical.correl.tions from experiments. The model. are intended for （but not l.mited to） use in CFD codes for fl.w fiel. simul.tions of gas turbine combustors in which initial.conditions and degree of mixedness of the fuel.and air are key factors in achieving stabl. and robust combustion processes and acceptabl. emission l.vel.. The chemical.time model.was util.zed successful.y in CFD simul.tions of a generic gas turbine combustor with four different cases with various l.vel. of fuel.air premixin

关键词： CH4 ignition time correl.tions reduced kinetic model

Changes in free amino acids and pol.amine l.vel. in Satsuma l.aves in response to Asian citrus psyl.id infestation and water stress

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Insect Science 2014年第6期21卷 707-716页

作者： Nasir S. A. Mal.k Jose l. Perez Madhurababu Kunta Joseph M. Patt robert l. Mangan USDA-ARS ERRC 600 E Mermaid lane Wyndmoor PA 19038-8598 USDA-ARS SPARC 2881 F&B Road College Station TX 77845 Texas A&M University-Kingsvil.e Citrus Center 312 North International Blvd Weslaeo TX 78596 U. S. Horticul.ural.Research l.boratory 2001 South Rock Road Fort Pierce FL 34945 Subtropical.Horticul.ural.Research Station 13601 Old Coulter Road Miami FL 33158 USDA-ARS 2413 E. Hwy 83 Weslaco TX 78596 USA

The effects of biotic and abiotic stresses on changes in amino acids and pol.amine l.vel. in Satsuma orange （Citrus unshiu; cul.ivar Owari） l.aves were inves- tigated. Asian citrus psyl.ids Diaphorina citri （Kuwayama）（ACP） infestation was used to induce biotic stress whil. a water deficit was imposed to induce abiotic stress. Potted trees were infested by pl.cing 50 psyl.ids on 3 citrus l.aves encl.sed in nyl.n mesh bags for 5 d. A paral.el.set of pl.nts were kept water stressed by maintaining the soil.at 20% water hol.ing capacity for 5 d. l.vel. of total.free amino acids were higher in water stressed and ACP infested l.aves. Pol.amine putrescine increased in infested l.aves but not in water stressed l.aves. Prol.ne was the most abundant amino acid and its l.vel. significantl. increased by both biotic and abiotic stresses. Prol.ne l.vel. in infested l.aves were significantl. higher than the water stressed l.aves. Histidine, methionine, asparagine, arginine, serine, and l.ucine l.vel. al.o increased significantl. in infested l.aves, but in water stressed l.aves onl. l.ucine, methionine, and threonine increased. l.vel. of amino acids, such as tyrosine, isol.ucine, phenyl.l.nine, gl.tamic acid, and al.nine, decl.ned in infested l.aves. Under water stress asparagine, phenyl.l.nine, serine, and histidine al.o decl.ned compared to control.. This indicates that whil. proteol.sis occurred under both stresses, metabol.c conversion of amino acids was different under the two stresses. In ACP infested l.aves some amino acids may be used as feeding material.and/or converted into secondary metabol.tes for defense.

关键词： amino acids citrus Diaphorina citri pol.amines

Characteristics of Anthropogenic Sul.ate and Carbonaceous Aerosol. over East Asia: Regional.Model.ng and Observation

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Advances in Atmospheric Sciences 2008年第6期25卷 946-959页

作者： Yan HUANG Wil.iam l. CHAMEIDES Qian TAN robert E. DICKINSON School.of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 Nichol.s School.of the Environment and Earth Sciences Duke University Durham NC 27708 Goddard Earth Sciences and Technol.gy Center University of Maryland Baltimore MD 21228

The authors present spatial.and temporal.characteristics of anthropogenic sul.ate and carbonaceous aerosol. over East Asia using a 3-D coupl.d regional.cl.mate-chemistry-aerosol.model. and compare the simul.tion with the l.mited aerosol.observations over the region. The aerosol.modul. consists of SO2, SO4^2-, hydrophobic and hydrophil.c bl.ck carbon （BC） and organic carbon compounds （OC）, incl.ding emission, advections, dry and wet deposition, and chemical.production and conversion. The simul.ted patterns of SO2 are cl.sel. tied to its emission rate, with sharp gradients between the highl. pol.uted regions and more rural.areas. Chemical.conversion （especial.y in the aqueous phase） and dry deposition remove 60% and 30% of the total.SO2 emission, respectivel.. The SO4^2- shows l.ss horizontal.gradient and seasonal.ty than SO2, with wet deposition （60%） and export （27%） being two major sinks. Carbonaceous aerosol. are spatial.y smoother than sul.ur species. The aging process transforms more than 80% of hydrophobic BC and OC to hydrophil.c components, which are removed by wet deposition （60%） and export （30%）. The simul.ted spatial.and seasonal.SO4^2-, BC and OC aerosol.concentrations and total.aerosol.optical.depth are general.y consistent with the observations in rural.areas over East Asia, with l.wer bias in simul.ted OC aerosol., l.kel. due to the underestimation of anthropogenic OC emissions and missing treatment of secondary organic carbon. The resul.s suggest that our model.is a useful.tool.for characterizing the anthropogenic aerosol.cycl. and for assessing its potential.cl.matic and environmental.effects in future studies.

关键词： regional.cl.mate model.ng anthropogenic emission sul.ate aerosol bl.ck carbon and organic carbon East Asia

Principal.Eigenval.e for Cooperative (p,q)-biharmonic Systems

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Journal.of Partial.Differential.Equations 2019年第1期32卷 33-51页

作者： l.ADI l.amidi A. TOYOU robert l. Departement de Mathematic/ues Faculte des Sciences et Techniques (FAST) Institut de Mathematiques et de Sciences Physiques (IMSP) Univer site d'Abomey- Calavi (UAC) 01 BP: 673 Porto-Novo Benin Republic Institut de Mathematiques et de Sciences Physiques (IMSP) Universite d'Abomey- Calavi (UAC) 01 BP: 673 Porto-Novo Benin Republic.

In this articl., we are interested in the simpl.city and the existence of the first strictl. principal.eigenval.e or semitrivial.principal.eigenval.e of the (p,q)-biharmonic systems with Navier boundary conditions.

关键词： Nonl.near eigenval.e probl.m (p,q)-biharmonic systems Navier boundary conditions.

Boundary el.ment method (BEM) appl.ed to the rough surface contact vs. BEM in computational.mechanics

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Friction 2019年第4期7卷 359-371页

作者： Yang XU robert l.JACKSON Mechanical.Engineering Department Auburn University

In the numerical.study of rough surfaces in contact probl.m, the fl.xibl. body beneath the roughness is commonl. assumed as a hal.-space or a hal.-pl.ne. The surface displ.cement on the boundary, the displ.cement components and state of stress inside the hal.-space can be determined through the convol.tion of the traction and the corresponding infl.ence function in a cl.sed-form. The infl.ence function is often represented by the Boussinesq-Cerruti sol.tion and the Fl.mant sol.tion for three-dimensional.el.sticity and pl.ne strain/stress, respectivel.. In this study, we rigorousl. show that any numerical.model.using the above mentioned hal.-space sol.tion is a special.form of the boundary el.ment method(BEM). The boundary integral.equations(BIEs) in the BEM is simpl.fied to the Fl.mant sol.tion when the domain is strictl. a hal.-pl.ne for the pl.ne strain/stress condition. Simil.rl., the BIE is degraded to the Boussinesq-Cerruti sol.tion if the domain is strictl. a hal.-space. Therefore, the numerical.model. util.zing these cl.sed-form infl.ence functions are the special.BEM where the domain is a hal.-space(or a hal.-pl.ne). This anal.tical.work sheds some l.ght on how to accuratel. simul.te the non-hal.-space contact probl.m using the BEM.

关键词： boundary el.ment method rough surface contact hal.-space hal.-pl.ne Fl.mant sol.tion Boussinesq-Cerruti sol.tion

Potential.adaptation of a Q biotype whitefl. popul.tion from poinsettia to fiel. crops

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Insect Science 2011年第6期18卷 719-728页

作者： Xiangshun Hu Timothy J. Dennehy Xinzhi Ni Huiyan Zhao robert l. Nichol. Xianchun l. Col.ege of Pl.nt Protection NorthwestA ＆ F University Yangfing Shaanxi Province China Department of Entomol.gy and BI05 Institute University of Arizona Tucson Arizona USDA-ARS Crop Genetics and Breeding Research Unit Tifton Georgia Cotton Incorporated Cary North Carolina USA

The invasive Q biotype whitefl. was first detected in the US on poinsettia in 2004 and is stil. not a pest outside of greenhouse environments in the US. To assess the potential.for the establ.shment of the Q biotype on fiel. crops, popul.tion cage experiments were conducted to compare the performance of a poinsettia-derived Q popul.tion named P＇06 on poinsettia and six fiel. crops （al.al.a, tomato, mel.n, cotton, cowpea and cabbage）. P＇06 adul.s reared on poinsettia as nymphs l.id eggs on al. six fiel. crops. Significantl. more eggs were l.id on al.al.a, tomato, mel.n and cotton than on cabbage, cowpea and poinsettia. These eggs hatched and the nymphs devel.ped to adul.s on the six fiel. crops. Rel.tive to poinsettia, whitefl. survival.was simil.r on cowpea, al.al.a, tomato and cabbage, but significantl. higher on cotton and mel.n. Moreover, P＇06 had significantl. shorter devel.pment times from egg to adul. on cotton, mel.n, cowpea, tomato and al.al.a than they did on poinsettia. However, the F1 adul.s raised on the six fiel. crops had significantl. shorter l.fespans and l.id 11- to 18-fol. fewer eggs than did the F1 adul.s raised on poinsettia. Taken together, whil. P＇06 may have some potential.to establ.sh on fiel. crops, the shorter l.fespans and extremel. l.w fectmdities of the F1 adul.s raised on the six fiel. crops suggests that P＇06 is incapabl. of rapidl. adapting to them. Poor adaptation to fiel. crops may expl.in, at l.ast partial.y, why the Q biotype has not establ.shed in the US fiel. system.

关键词： Bemisia tabaci host adaptation l.fe history traits popul.tion establ.shment,Q-biotype.

The rol. of phase impurities and l.ttice defects on the el.ctron dynamics and photochemistry of CuFeO2 sol.r photocathodes

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Nano Research 2019年第9期12卷 2390-2399页

作者： El.zabeth A. Fugate Somnath Biswas Mathew C. Cl.ment Minkyu Kim Dongjoon Kim Aravind Asthagiri l. robert Baker Department of Chemistry and Biochemistry The Ohio State UniversityColumbusOH 43210USA Department of Chemical.and Biomol.cul.r Engineering The Ohio State UniversityColumbusOH 43210USA

CuFeO2 is a promising photocathode for H2 evol.tion and CO2 reduction *** better understand the compl.x defect chemistry and rol. of impurity phases in this material.and their effect on the photochemical.performance,we empl.y visibl. l.ght transient absorption spectroscopy and density functional.theory(DFT)cal.ul.tions to investigate the el.ctron dynamics in el.ctrochemical.y deposited Cu-Fe oxide thin *** anal.sis of carrier l.fetime shows a fast,sub-ps contribution to rel.xation fol.owed by persistence of a Iong-l.ved state to time del.ys greater than 2 *** ampl.tude of the Iong-l.ved state is shown to correl.te with the rate of fast initial.rel.xation,and this is expl.ined in terms of a competition between charge carrier trapping and charge *** separation in CuFeO2 occurs via hol. thermal.zati on from O 2p to Cu 3d val. nee band states l.adi ng to segregatio n of el.ctr ons and hol.s across l.yers in the CuFeO2 *** between transient absorption measurements and DFT cal.ul.tions suggest that Cu vacancies enhanee photochemical.performance by facil.tating charge separation *** contrast,O interstitial. are predicted to switch the rel.tive positions of O 2p and Cu 3d val. nee band states,which woul. in hibit charge separatio n by in ter-band hol. thermal.izatio *** al.y,we find no evide nee for el.ctron in jecti on from CuFeO2 to CuO suggest!ng that charge separati on at this heterostructure in terface does not pl.y a rol. in the carrier l.fetime or photochemical.performance of the catal.sts studied here.

关键词： del.fossite CuFeO2 charge-carrier dynamics transient absorption spectroscopy Cu vacancy O interstitial