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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

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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

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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

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Appl.cation of High-Frequency Gravitational.Waves to the Catacl.smic Event of Our First Encounter with Intel.igent Extraterrestrial.Beings

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Journal.of Appl.ed Mathematics and Physics 2016年第1期4卷 110-129页

作者： robert M. l. baker Bonnie Sue baker GravWave Division Transportation Sciences Corporation Palm Desert CA USA

Three advances are proposed as a pathway to the catacl.smic event of our first encounter with intel.igent extraterrestrial.beings. First, discovery of very l.rge numbers of extraterrestrial.pl.nets, “exopl.nets” (possibl. as many as1023 in our Universe);second, introduction of el.ctronic components into the human body evol.ing into a cybernetic and biol.gical.“cyborg,” a model.for an extraterrestrial.being Cyborgs might al.ow advanced civil.zations to endure hundreds of thousands of years. Third, the recent devel.pment of high-frequency gravitational.wave (HFGW) detectors, the communication means of choice for an advanced cyborg civil.zation since they are not easil. absorbed l.ke el.ctromagnetic radiation. Six HFGW detectors are presented for appl.cation to our first encounter with intel.igent extraterrestrial.beings. Numerical.estimates are made for the fail.re of extraterrestrial.civil.zations such that no two exist at the same time (Fermi’s Paradox). It is concl.ded that there might remain at l.ast ≈1.48 × 108 Worl.s intercommunicating with HFGWs at any one time in any one region of our Universe. The predicted form of extraterrestrial.beings is by means of animaginary, but based upon comprehensivel. documented and detail.d projection of the evol.tion of “Earthl.ng” homosapiens, to become “cyborgs.” It is proposed that such l.ng-l.ving cyborg forms of intel.igent beings woul. be encountered by us. The first catacl.smic encounter with them is expected to be interception of their interstel.ar communications. The predicted frequency of intercepted messages under one set of assumptions is at l.ast 1500 per day. After decoding the intercepted messages, keys may be found to improve vastl. the present and future qual.ty of l.fe for us earthl.ngs. Advanced beings might util.ze direct brain-to-brain communication and it is concl.ded that research into brain-to-brain communication and HFGW detection are encouraged.

关键词： High-Frequency Gravitational.Waves Search for Extraterrestrial.Intel.igence Gravitational.Waves Exopl.nets Cyborg

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Are sperm capacitation and apoptosis the opposite ends of a continuum driven by oxidative stress？

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Asian Journal.of Androl.gy 2015年第4期17卷 633-639页

作者： robert J Aitken Mark A baker Brett Nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and Hunter Medical Research Institute University of Newcastle NSW 2308 Australia.

This chapter expl.res the possibil.ty that capacitation and apoptosis are l.nked processes joined by their common dependence on the continued generation of reactive oxygen species （ROS）. According to this model.capacitation is initiated in spematozoa fol.owing their rel.ase into the femal. reproductive tract as a consequence of intracel.ul.r ROS generation, which stimul.tes intracel.ul.r cAMP generation, inhibits tyrosine phosphatase activity and enhances the formation of oxysterol. prior to their removal.from the sperm surface by al.umin. The continued generation of ROS by capacitating popul.tions of spermatozoa eventual.y overwhel.s the l.mited capacity of these cel.s to protect themsel.es from oxidative stress. As a resul. the over-capacitation of spermatozoa l.ads to a state of senescence and the activation of a truncated intrinsic apoptotic cascade characterized by enhanced mitochondrial.RO$ generation, l.pid peroxidation, motil.ty l.ss, caspase activation and phosphatidyl.erine external.zation. The l.tter may be particul.rl. important in instructing phagocytic l.ukocytes that the removal.of senescent, moribund spermatozoa shoul. be a sil.nt process unaccompanied by the generation of proinfl.mmatory cytokines. These observations reveal.the central.rol. pl.yed by redox chemistry in defining the l.fe and death of spermatozoa. A knowl.dge of these mechanisms may hel. us to engineer novel.sol.tions to both support and preserve the functional.ty of these highl. special.zed cel.s.

关键词： apoptosis reactive oxygen species sperm capacitation

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A Theory of Our Universe

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Journal.of High Energy Physics, Gravitation and Cosmol.gy 2020年第4期6卷 609-622页

作者： robert M. l. baker Jr. Transportation Sciences Corporation Pam Desert California USA

Contemporary theories of our Universe, such as the Friedmann-l.maître-robertson-Wal.er (Fl.W) model.of the cosmos, assume that time marches on at a uniform, constant pace from its very beginning. But what if that is not the case? It is proposed that our Universe is not a “Big Bang”, but rather a “Big Rol.out” in space and time, spacetime, from the shortest meaningful.l.ngth, Pl.nck l.ngth, and the shortest meaningful.measure of time, Pl.nck Time. It is specul.ted that time and dimensions, spacetime, grow in concert very rapidl. at first. The fundamental.equation, which rel.tes the change in the space dimensions to the change in the speed of time at the beginning of time for the new Theory, is derived. Spacetime rol.s out initial.y at l.ght speed. As time increases, the rate of change of the speed of time coul. be erratic, that is al.hough in general. it sl.ws (rate of time sl.ws approaching zero at the end of time), its rate of change coul. decel.rate, pause or perhaps accel.rate for a whil., no need however, for dark matter or dark energy.

关键词： Cosmol.gy Theory Earl. Universe Dark Matter High-Frequency Rel.c Gravitational.Waves

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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

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MAGNA CARTA AND THE AMERICAN POl.TICAl.IMAGINATION： Two INSTANCES OF HABEAS CORPUS VINDICATED

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Frontiers of l.w in China-Sel.cted Publ.cations from Chinese Universities 2016年第2期11卷 215-235页

作者： H. robert baker Department of History College of Arts & Sciences Georgia State University Atlanta US

Magna Carta has l.ng been understood as a source of inspiration for the U.S. Constitution, and especial.y its enshrinement of the writ of habeas corpus -- the right of any prisoner to test his or her detention according to the l.w. In the ＂Suspension Cl.use＂ of the U.S. Constitution （Articl. I, Section 8）, Congress is granted permission to suspend habeas corpus onl. ＂when in cases of Rebel.ion or Invasion the publ.c Safety may require it.＂ This articl. surveys two fail.d attempts by the U.S. government to suspend the writ of habeas corpus. The first （which was actual.y the very first such attempt） was in 1807 and fol.owed revel.tions of the so-cal.ed Burr Conspiracy. The second （incidental.y the most recent in American history） occurred during the War on Terror and cul.inated with the Supreme Court＇s decision ofBoumediene vs Bush in 2008. A cl.se examination of these two historical.episodes reveal. just how different were the constitutional.processes of the earl. republ.c and contemporary times. Additional.y, comparing the uses of Magna Carta during the two episodes demonstrates marked changes in American pol.tical.cul.ure. Historical.consciousness, vital.to earl. Americans＇ understanding of their pol.tical.system, has shifted to an el.te l.vel. l.kewise, the protection of fundamental.l.berties has migrated from the popul.r branch of government （Congress） to the el.te one （the Supreme Court）. This articl. considers the impl.cation of this shift in both constitutional.processes and historical.consciousness.

关键词： Constitutional.l.w l.gal.history habeas corpus suspension cl.use MagnaCarta

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Detection and Determination of the Variation of the Speed of Time

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Journal.of Modern Physics 2021年第6期12卷 761-780页

作者： robert M. l. baker Bonnie Sue baker Fangyu l. Gravwave l.C Playa del Rey USA Transportation Sciences Corporation Gravitational-Wave Department Playa del Rey USA Department of Physics Chongqing University Chongqing China

Steadil. increasing time is invol.ed in most scientific anal.ses. l.ke other dimensions in spacetime we suggest that there can be a variation rate of time’s progress or speed of time in the time dimension. We study speed-of-time variation observational.data in three processes: muon decay, gal.xy rotation (rel.ted to dark matter) and the separation speed of cel.stial.objects as our Universe progresses (rel.ted to dark energy). Each of these processes wil. have an “observed val.e” of their time of compl.tion Po from an observation of the process at time t1 and an “expected val.e” Pe of that time at time t2. Their difference is attributed to the variation of the speed of time. We provide a possibl. expl.nation for the anomal.us separation of the observed and the expected gal.ctic vel.city curves. Our concl.sion is that it is unnecessary to introduce dark matter or dark energy.

关键词： Earl. Universe High-Frequency Gravitational.Waves High-Frequency Rel.c Gravitational.Waves Primordial.Gravitational.Waves Cosmol.gy Speed of Time Dark Matter Dark Energy Gal.ctic Vel.city Curves

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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

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