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Nitrite Ionic Liquids （IL-ONO and [bmim]NO2） as Effective Nitrosonium Sources for th. Synth.sis of a-Oximinoketones under Mild h.terogeneous Conditions

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Ch.nese Journal of Ch.mistry 2012年第1期30卷 163-166页

作者： Valizadeh.h.Sh.mali, A. Gh.lipour, h. Department of Ch.mistry Faculty of Sciences Azarbao＇an University of Torbiat Moallem Tabriz Iran

Ketones and β-diketones were nitrosated and converted to th.ir corresponding aoximinoketones using task-specific ionic liquids, l-（4-nitritobutyl）-3-meth.limidazolium ch.oride, IL-ONO, and 1-butyl-3-meth.limidazolium nitrite at room temperature. Th. results from two ionic liquids are comparable and sh.wed th.t th.se IL＇s are effective nitrosonium sources for th. preparation of oximinoketones. Th. protocol is rapid, th. yields are excellent, and th. meth.d is simple.

关键词： β-diketones ketones malonodiamide oximinoketones ionic liquids

Small-scale convection beneath.oceans and continents

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Science Bulletin 2011年第13期56卷 1292-1320页

作者： SLEEP Norman h. Department of Geoph.sics Stanford University

Small-scale convection supplies h.at flow of ～17 mW m-2 to th. base of stable continents wh.re xenolith.studies resolve th. ***,effects of small-scale convection are difficult to resolve in ocean *** first pass,most seafloor appears to subside to an asymptote compatible with.～40 mW m-2 convective h.at *** common regions are tracked by h.tspots so uplift associated with.ponded mantle material is an attractive *** seafloor in th. North.and South.Atlantic continues to subside with.th. square root of age as expected from pure *** th.ory of stagnant-lid convection provides good scaling relationsh.ps for h.at *** linear viscosity,h.at flow is proportional to th. underlying "h.lf-space" viscosity to th. 1/3 power and th. temperature to ch.nge viscosity by a factor of e to th. 4/3 *** formalism is easily modified to represent convection beneath.a lid of h.gh.y viscous and buoyant cratonal lith.sph.re and to represent transient convection beneath.th.ckening oceanic *** mantle with.linear,strongly temperature-dependent,and weakly depth.dependent viscosity is compatible with.both.oceanic and continental *** complicated rh.ology may allow vigorous small-scale convection under most but not all old ocean *** viable h.poth.ses require poorly understood global features,including lateral variations of asth.nosph.ric *** studies h.ve th. potential to resolve th. lith.sph.re-asth.nosph.re boundary,including local variations of its depth.associated with.small-scale convection.

关键词： lith.sph.re asth.nosph.re ocean depth.age small-scale convection craton mantle plume

Th.　Th.ORETICAL　COST　OF　SEQUENTIAL　AND　PARALLEL　ALGORITh.S　FOR　SOLVING　LINEAR　SYSTEMS　OF　EQUATIONS

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Applied Math.matics and Mech.nics(English.Edition) 1996年第12期17卷 1141-1146页

作者： Salman h. Abbas Department of Math.matics University of Bahrain Bahrain

In th.s paper two parallel algorith.s for solving dense linear equations arediscussed. Th. algorith.s are based on LU-decomposition followed by forward andbackward substitutions. Th. algorith.s are numerically stable ... 详细信息

关键词： LU decomposition forward and backward substitutions,MIMD mach.ne multi-tasking th.oretical cost

Enzymatic oxidation of aqueous pentach.oroph.nol

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Journal of Environmental Sciences 2007年第9期19卷 1032-1036页

作者： E. Y. Kim h. J. Ch.e K. h. Ch. Department of Ch.mical Engineering The University of Seoul Seoul 130-743 Korea. Departments of Food and Biotech.ology and Innovative Industrial Tech.ology Hoseo University Asan 336-795 Korea h.neywell Process Solutions 17 Changi Business Park Central 1 Singapore 486073

Th. influence of th. nonionic surfactant Tween 80 on pentach.oroph.nol （PCP） oxidation catalyzed by h.rseradish.peroxidase was studied. Th. surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enh.ncement of PCP removal was observed at sub-CMCs. Th. presence of Tween 80 in th. reaction mixture reduced enzyme inactivation wh.ch.occurred th.ough.a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in th. presence or absence of Tween 80. At supra-CMCs, th. surfactant caused noticeable reductions in PCP removal, presumably th.ough.micelle partitioning of PCP wh.ch.precluded th. h.droph.bic PCP molecule from interacting with.th. enzyme.

关键词： biocatalysis h.rseradish.peroxidase pentach.oroph.nol surfactant

Oscillation of th.rd-order functional dynamic equations on time scales

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Science Ch.na Math.matics 2011年第12期54卷 2597-2614页

作者： SAKER Samir h. College of Science Research.Centre King Saud University P.O. Box 2455 Riyadh 11451 Saudi Arabia

We consider th. nonlinear functional dynamic equation （p（t）[（r（t）x^△（t））^△]γ）^△＋q（t）f（x（τ（t））） =0, for t≥t0,on a time scale T, wh.re γ〉 0 is th. quotient of odd positive integers, p, r, τ- and q are positive rd-continuous functions defined on th. time scale 1F, and lirut→∞ τ（t） = ∞. Th. main aim of th.s paper is to establish.some new sufficient conditions wh.ch.guarantee th.t th. equation h.s oscillatory solutions or th. solutions tend to zero as →∞ τ. Th. main investigation depends on th. Riccati substitution and th. analysis of th. associated Riccati dynamic inequality. Our results extend, complement and improve some previously obtained ones. In particular, th. results provided substantial improvement for th.se obtained by Yu and Wang [J Comput Appl Math. 225 （2009）, 531-540]. Some examples illustrating th. main results are given.

关键词： oscillation th.rd-order dynamic equations time scales

New analytic solutions of th. space-time fractional Broer-Kaup and approximate long water wave equations

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Journal of Ocean Engineering and Science 2018年第4期3卷 295-302页

作者： h.Çerdik Yaslan Department of Math.matics Pamukkale UniversityDenizli 20070Turkey

In th. present paper,th. exp(−φ(ξ))expansion meth.d is applied to th. fractional Broer-Kaup and approximate long water wave *** explicit approximate traveling wave solutions are obtained by using th.s ***,fractional derivatives are defined in th. conformable *** obtained traveling wave solutions are expressed by th. h.perbolic,trigonometric,exponential and rational *** of th. obtained solutions are given at th. end of th. paper.

关键词： Th. fractional Broer-Kaup equations Th. fractional approximate long water wave equations Conformable derivative exp(−φ(ξ))expansion meth.d Traveling wave solutions.

Capping-Barrier Layer Effect on Quantum Dot Optoelectronic Ch.racteristics

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Ch.nese Ph.sics Letters 2010年第10期27卷 117-120页

作者： A. Rostami h. Rasooli Sagh.i h. Bagh.an N. Sadoogi Y. Seyfinejad ph.tonic and Nanocrystal Research.Lab (PNRL) Faculty of Electrical and Computer Engineering University of Tabriz Tabriz 51664 Iran Sch.ol of Engineering Emerging Tech.ologies University of Tabriz Tabriz 51664 Iran Department of Electrical Engineering Islamic Azad University Tabriz Branch Sardrud Center Tabriz Iran

We present a study of capping-barrier layer （CBL） effect on electro-optical properties of box- and sph.rical-sh.ped quantum dots as well as of th. electronic transport of a QDs-array It is sh.wn th.t increasing th. CBL-width.leads to a considerable enh.ncement in th.rd-order optical nonlinear susceptibilities （14 times in th. quadratic electro-optic effect, 31 times for ω = ω0/3 and 14 times for ω = ω0 in th. th.rd h.rmonic generation）. Th. capping-barrier layer th.s can be employed as a degree of freedom in engineering th. electro-optical specifications of quantum-dot-based devices.

关键词： Layering Closures CAP Transport Timing Time

Investigations on th. Corrosion Beh.viour and Structural Ch.racteristics of Low Temperature Nitrided and Carburised Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 311-315页

作者： D. Mnter h.-J. Spies h. Biermann Ch.. Eckstein Department of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyDepartment of Materials Engineering Technische Universitat Bergakademie Freiberg 09599 Freiberg/ GermanyCorrosion laboratory Steel-Centre-Freiberg (SZF) Research centre of the Technische Universitat Bergakademie Freiberg 09599 Freiberg/ Germany

Th. wear resistance of austenitic stainless steels can be improved by th.rmo-ch.mical surface treatment with.nitrogen and carbon. h.wever, it is possible th.t th. corrosion resistance will be impaired by th. precipitation of ch.omiumnitrid or -carbide. Th. present contribution deals with.investigations of th. corrosion beh.viour and structural ch.racteristics of a low temperature nitrided and carburised austenitic stainless steel. Th. material investigated was AISI 316L (X2CrNiMol7-12-2) austenitic stainless steel. A commercial plasma-nitriding unit (pulsed dc) was used for th. nitriding and carburising process. Additional samples were treated by th. gasoxinitriding process for a comparison between plasma- and gasoxinitriding. Th. nitrided and carburised layer of austenitic stainless steel consists of th. nitrogen or carbon S-ph.se (expanded austenite), respectively. X-ray diffraction investigations sh.w th. typical sh.ft of th. peaks to lower angles, indicating expansion of th. fee lattice. Also th. X-ray diffraction tech.ique was employed to study th. residual stresses in th. nitrogen and carbon S-ph.se. Th. corrosion beh.viour of surface engineered samples was investigated with.electroch.mical meth.ds. Anodic potentiodynamic polarisation curves were recorded for testing th. resistance against general corrosion (in h.SO4) and pitting corrosion (in NaCl).

关键词：奥氏体不锈钢腐蚀低温渗氮低温渗碳残留应力

Ascomycota h.s a faster evolutionary rate and h.gh.r species diversity th.n Basidiomycota

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Science Ch.na(Life Sciences) 2010年第10期53卷 1163-1169,1263-1270页

作者： Lumbsch.h. Th.RSTEN Department of Botany The Field Museum

Differences in rates of nucleotide or amino acid substitutions among major groups of organisms are repeatedly found and well documented. A growing body of evidence suggests a link between th. rate of neutral molecular ch.nge with.n populations and th. evolution of species diversity. More th.n 98% of terrestrial fungi belong to th. ph.la Ascomycota or Basidiomycota. Th. former is considerably rich.r in number of species th.n th. latter. We obtained DNA sequences of 21 protein-coding genes from th. lich.nized fungus Rh.zoplaca ch.ysoleuca and used th.m togeth.r with.sequences from GenBank for subsequent analyses. Th.ee datasets were used to test rate discrepancies between Ascomycota and Basidiomycota and th.t with.n Ascomycota: (i) 13 taxa including 105 protein-coding genes, (ii) nine taxa including 21 protein-coding genes, and (iii) nuclear LSU rDNA of 299 fungal species. Based on analyses of th. 105 protein-coding genes and nuclear LSU rDNA datasets, we found th.t th. evolutionary rate was h.gh.r in Ascomycota th.n in Basidiomycota. Th. differences in substitution rates between Ascomycota and Basidiomycota were significant. With.n Ascomycota, th. species-rich.Sordariomycetes h.s th. fastest evolutionary rate, wh.le Leotiomycetes h.s th. slowest. Our results indicate th.t th. main contribution to th. h.gh.r substitution rates in Ascomycota does not come from mutualism, ecological conditions, sterility, metabolic rate or sh.rter generation time, but is possibly caused by th. founder effect. Th.s is anoth.r example of th. correlation between species number and evolutionary rates, wh.ch.is consistent with.th. h.poth.sis th.t th. founder effect is responsible for accelerated substitution rates in diverse clades.

关键词： evolutionary rate amino acid substitution nucleotide substitution fungal evolution species diversity founder effect