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Cobalt(Ⅱ) ch.oride accelerated one-pot th.ee-component synth.sis of α-aminoph.sph.nates at room temperature

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Ch.nese Ch.mical Letters 2011年第5期22卷 559-562页

作者： Zah.d Karimi-Jaberi h.ssan Zare Moh.mmad Amiri Nagh.eh.sadeghi Department of Ch.mistry Islamic Azad UniversityFiroozabad BranchP.O.Box 74715-117FiroozabadFarsIran

A simple,efficient,and general meth.d h.s been developed for th. one-pot,th.ee-component synth.sis ofα-aminoph.sph.nates from condensation reaction of trimeth.l ph.sph.te,aryl aldeh.des and aryl amines in th. presence of CoCl_2-6h.2O under solvent-free ***α-aminoph.sph.nates were synth.sized relatively quickly in good yields at room temperature.

关键词： α-Aminoph.sph.nates Cobalt(Ⅱ) ch.oride Trimeth.l ph.sph.te Room temperature Solvent-free

Numerical Algorith. for Solving Multi-Pantograph.Delay Equations on th. h.lf-line Using Jacobi Rational Functions with.Convergence Analysis

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Acta Math.maticae Applicatae Sinica 2017年第2期33卷 297-310页

作者： Eid h. DOh. Ali h. Bh.AWY Ramy M. h.FEZ Department of Math.matics Faculty of Science Cairo University Giza Egypt Department of Math.matics Faculty of Science King Abdulaziz University Jeddah Saudi Arabia Department of Math.matics Faculty of Science Beni-Suef University Beni-Suef Egypt Department of Math.matics Alwagjh University College University of Tabuk Tabuk Saudi Arabia Department of Basic Science Institute of Information Technology Modern Academy Cairo Egypt

A new spectral Jacobi rational-Gauss collocation （JRC） meth.d is proposed for solving th. multi- pantograph.delay differential equations on th. h.lf-line. Th. meth.d is based on Jacobi rational functions and Gauss quadrature integration formula. Th. main idea for obtaining a semi-analytical solution for th.se equations is essentially developed by reducing th. pantograph.equations with.th.ir initial conditions to systems of algebraic equations in th. unknown expansion coefficients. Th. convergence analysis of th. meth.d is analyzed. Th. meth.d possesses th. spectral accuracy. Numerical results indicating th. h.gh.accuracy and effectiveness of th.s algorith. are presented. Indeed, th. present meth.d is compared favorably with.oth.r meth.ds.

关键词： multi-pantograph.equation delay equation collocation meth.d Jacobi-Gauss quadrature Jacobirational functions convergence analysis

Sudden enh.ncement of sedimentation flux of^(210)Pb_(ex) as anindicator of lake productivity as exemplified by Lake Ch.ngh.i

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Science Ch.na Earth.Sciences 2005年第4期48卷 484-495页

作者： P. h. Santsch. Department of Marine Sciences Texas A&M University Galveston Texas 77551 USA

Th. fundamental assumption of 210Pbsediment dating is th. stable flux of 210Pbse, wh.ch.was derived from atmosph.re and th.n transferred into sediments via lake water. Wh.n th. sedimentation rate is relatively constant, th. 210Pbse activity in sediments will be exponentially reduced with.sedimentation age. 210Pbse in lake water is incorporated into sediments mainly via organic particulates. If th. sedimentation flux of organic matter in lake water is suddenly in- creased, 210Pbse will be significantly deposited and th.n transferred into sediments. On th. one h.nd such.sudden purification effect is obviously unfit for th. fundamental assumption of 210Pbse dating; on th. oth.r h.nd, th. sudden enh.ncement of 210Pbse flux would be indicative of th. conspicuous variation of primary productivity of lake water. Th.s problem will be discussed in accordance with.th. variation trend of 210Pbex in th. vertical profile of recent sediments of Lake Ch.ngh.i, Yunnan Province. Th. sediment core was collected from th. deep-water area of Lake Ch.ngh.i in June 1997. Th. vertical profile of 137 Cs activity is ch.racterized by a tree-peak pat- tern. Th.s profile gave reliable ages, and also sh.wed th. stability of sediment accumulation in th. recent ten years. Th. vertical profile of210Pbse activity displays a specific distribution of peaks, and is similar to th. vertical profile of Corg. Th.s ph.nomenon seems to be related to th. mech.- nism of constraining th. transfer of 210Pbse into lake sediments. Th. average atomic ratios of h.rg/Corg and Corg/Norg in Lake Ch.ngh.i sediments are 5.51 and 7.04, respectively, indicating th.t th. organic matter was predominantly derived from th. remains of endogenic algae. In terms of th. th.ee-stage evolutionary ch.racteristics of organic matter in sediments, i.e., “deposition-de- composition-accumulation”, th. sedimentation fluxes （F（Corg）） of organic carbon （Corg） since 1970 were calculated by modeling. Th. sedimentation fluxes of 210Pbse (F(210P

关键词： sudden purification effect, 210Pbex, primary productivity of lake, Lake Ch.ngh.i.

Th. synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene promoter on activation of PglaA transcription

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Science Ch.na(Life Sciences) 2004年第2期47卷 139-147页

作者： WANG h. M. Genencor International Inc. 925 Page Mill Road Palo Alto California 94304 USA

EMSA and footprinting analyses h.ve revealed th.t th. -489—-414 bp and th. -390—-345 bp (designated DC and PC respectively) upstream of th. Aspergillus niger T21 glaA gene were bound by one protein factor in th. A. niger T21 wh.le cell extract. Both.DC and PC contained CCAAT pentanucleotides. Th. functions of DC and PC in regulation of expression of glucoamylase (GLA) were studied. CCAAT pentanucleotides were replaced with.CGTAA and th. mutated DNA fragments DCm and PCm lost th. binding activities of protein factors in vitro. In vivo wh.n eith.r DC or PC was mutated or th. relative orientations between th.m were ch.nged on th. PglaA, th. transcriptional activity of PglaA decreased to a basal level. Introduction of multi-copies of DC into th. original site at th. PglaA in A. niger T21 decreased th. expression of endogenous GLA expression and th. exogenous reporter E. coli uidA gene introduced under th. PglaA promoter, wh.le h.ving no effect on th. uidA gene under th. control of PgpdA. EMSA re-vealed th.t th. levels of th. specific DNA-binding protein factors in th. transformants maintained th. same meaning th.t introduction of multi-copies of DC caused th. titration effect. Angh.pC gene was cloned from A. niger T21 cDNA and introduced into th. DC multi-copied strains. Th. expression of Angh.pC improved th. expression of th. endogenous GLA and th. exogenous gene controlled by PglaA. Th.se results sh.wed th.t both.th. CCAAT pentanucleotides were necessary for DC and PC binding to th. protein factors, and th. simultaneous binding of DC and PC to th. protein was necessary for promoting th. transcriptional activity of PglaA. Angh.pC was th. specific positive trans-acting protein factor binding to DC.

关键词： Aspergillus niger glucoamylase, synergetic effect, mutation analysis, multi-copy of CCAAT box, titration effect.

Tree water potentials supporting an explanation for th. occurrence of Vach.llia erioloba in th. Namib Desert (Namibia)

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Forest Ecosystems 2017年第4期4卷 303-312页

作者： Joach.m h. A. Krug Institute for Silviculture and Forest Ecology Georg-August-University of Gottingen Bosgenweg 1 37077 Gottingen Germany

Background： Site-vegetation relations of Vach.llia erioloba, Faidh.rbia albido, Euclea pseudebenus and Tamarix usneoides in two contrasting locations in th. Namib Desert （Namibia） were evaluated with.th. goal to relate soil water availability to th. occurrence of trees under h.per-arid conditions, Meth.ds： Plant water potentials were measured using a pressure ch.mber in th. field. Pre-dawn water potentials were assessed to reflect th. soil water potential of th. rh.zosph.re. Midday water potentials were measured to assess th. strongest negative water potential applied by th. sample trees. Results： Pre-dawn water potentials and midday water potentials indicated access to soil water in th. rh.zosph.re and by th.s, provide an explanation for an occurrence of V. erioloba with.n th. extreme environmental conditions of sand dunes in th. Namib Desert. Diurnal ranges seem to reflect more and less suitable stands, in terms of soil water availability, with.n th. sampling sites. Wh.le th. impact of th. eph.meral Kuiseb river on soil water availability was assessed th.ough.th. four species＇ plant-internal water relations, comparable pre-dawn water potentials of V. erioioba at both.sites indicate soil water availability also in th. dunes of Namibrand. Th. extreme midday water potentials of th. dune plants possibly sh.w th. upper limit of tolerance for V. eriolobo. Conclusions： Th. preliminary data provide an explanation of th. occurrence and distribution of th. investigated species in beds of eph.meral rivers and on dunes under th. h.per-arid climatic conditions of th. Namib Desert and qualify suitability with.n th. assessed sites. Understanding th. plant-ph.siological processes and assessing th. plant-internal water potential provides a valuable tool to evaluate soil water availability with.n th. rh.zosph.re and to describe an adaptation potential of investigated species. Th. comparability of pre-dawn water potentials at both.sites indicates unexpected soil water availability w

关键词： Water potential Arid land Soil water availability Namibia V. erioloba

TIME AND NORM OPTIMAL CONTROLS:A SURVEY OF RECENT RESULTS AND OPEN PROBLEMS

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Acta Math.matica Scientia 2011年第6期31卷 2203-2218页

作者： h. O. Fattorini Department of Math.matics University of California Los Angeles

We present in th.s paper a survey of recent results on th. relation between time and norm optimality for linear systems and th. infinite dimensional version of Pontryagin＇s maximum principle. In particular, we discuss optimality （or nonoptimality） of singular controls satisfying th. maximum principle and smooth.ess of th. costate in function of smooth.ess of th. target.

关键词： linear control systems in Banach.spaces time optimal problem norm optimal problem

Low-lying states and isospin excitation in th. Ge isotopes

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Ch.nese Ph.sics C 2009年第7期33卷 538-546页

作者： Falih.h. Al-Kh.dair Department of Ph.sics Tsinghua University Center of Nuclear Th.ory Lanzhou Heavy Ion National Laboratory Department of Ph.sics College of EducationBasrah University

Th. level structure of ^64-70Ge isotopes h.s been studied with.n th. framework of th. interacting boson model-3（IBM-3） . Th. symmetry ch.racter in th. proton and neutron degrees of freedom of th. energy levels h.s been investigated. Th. isospin excitation states（T 〉 Tz） h.ve been assigned for th. ^64Ge（N = Z） nucleus. Some intruder states in th.se nuclei h.ve been suggested. Th. calculated energy levels and transition probabilities are in good agreement with.recent experimental data. Th. study indicates th.t th. Ge isotopes are in transition from γ-unstable to vibrational.

关键词： IBM-3 Isospin Z ≈ N nuclei, ^64-70Ge isotopes

Cloning and ch.racterization of a FLORICAULA/LEAFY orth.log, PFL, in polygamous papaya

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Cell Research 2005年第8期15卷 576-584页

作者： Paul h. MOORE,h.nrik h. ALBERT,Adrienne h.K. ROADER,Ray MING USDA-ARS Pacific Basin Agricultural Research.Center Aiea h. 96701 USA USDA-ARS Pacific Basin Agricultural Research.Center Aiea h. 96701 USA Section of Cell and Developmental Biology University of California San Diego La Jolla CA 92093 USA h.waii Agriculture Research.Center Aiea h. 96701 USA

Th. h.mologous genes FLORICAULA (FLO) in Antirrh.num and LEAFY (LFY) in Arabidopsis are known to regu- late th. initiation of flowering in th.se two distantly related plant species. Th.se genes are necessary also for th. expression of downstream genes th.t control floral organ identity. We used Arabidopsis LFY cDNA as a probe to clone and sequence a papaya orth.log of LFY, PFL. It encodes a protein th.t sh.res 61% identity with.th. Arabidopsis LFY gene and 71% identity with.th. LFY h.mologs of th. two woody tree species: California sycamore (Platanus racemosa) and black cottonwood (Populus trich.carpa). Despite th. h.gh.sequence similarity with.n two conserved regions, th. N-terminal proline-rich.motif in papaya PFL differs from oth.r members in th. family. Th.s difference may not affect th. gene function of papaya PFL, since an equally divergent but a functional LFY orth.log NEEDLY of Pinus radiata h.s been reported. Genomic and BAC South.rn analyses indicated th.t th.re is only one copy of PFL in th. papaya genome. In situ h.bridization experiments demonstrated th.t PFL is expressed at a relatively low level in leaf primordia, but it is expressed at a h.gh.level in th. floral meristem. Quantitative PCR analyses revealed th.t PFL was expressed in flower buds of all th.ee sex types - male, female, and h.rmaph.odite with.marginal difference between h.rmaph.odite and unisexual flowers. Th.se data suggest th.t PFL may play a similar role as LFY in flower development and h.s limited effect on sex differentiation in papaya.

关键词： divergence floral meristem identity gene flower development gene expression molecular ph.logeny.

Specimen aspect ratio and progressive field strain development of sandstone under uniaxial compression by th.ee-dimensional digital image correlation

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Journal of Rock Mech.nics and Geotech.ical Engineering 2017年第4期9卷 599-610页

作者： h. Munoz A. Tah.ri Deep Exploration Tech.ologies Cooperative Research.Centre (DET CRC) Export Park Adelaide Airport Adelaide SA 5950 Australia Sch.ol of Civil Environmental & Mining Engineering The University of Adelaide Adelaide SA 5005 Australia

Th. complete stress-strain ch.racteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression *** patterns development during pre-and post-peak beh.viours in specimens with.different aspect ratios was also *** stress,post-peak portion of stress-strain,brittleness,ch.racteristics of progressive localisation and field strain patterns development were affected at different extents by specimen aspect *** patterns of th. rocks were obtained by applying th.ee-dimensional(3D) digital image correlation(DIC) *** conventional strain measurement using strain gauges attach.d to specimen,3D DIC allowed not only measuring large strains,but more importantly,mapping th. development of field strain th.ough.ut th. compression test,*** pre-and post-peak *** strain development in th. surface of rock specimen suggests th.t strain starts localising progressively and develops at a lower rate in pre-peak ***,in post-peak regime,strains increase at different rates as local deformations take place at different extents in th. vicinity and outside th. localised *** extent of localised strains togeth.r with.th. rate of strain localisation is associated with.th. increase in rate of strength.*** localisation and local inelastic unloading outside th. localised zone both.feature post-peak regime.

关键词： Uniaxial compression test Aspect ratio Strain patterns Digital image correlation(DIC)