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Nonlinear vibrations of nano-beams ac.ounting for nonloc.l effec. using a multiple sc.le method

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2009年第3期52卷 617-621页

作者： c. W. LIM Department of Building and c.nstruc.ion City University of Hong Kong

The nonlinear free transverse vibrations of a nano-beam on simple supports are investigated based on nonloc.l elastic.ty theory. The governing equation is proposed by c.nsidering geometric.nonlinearity due to finite stretc.ing of the beam. The method of multiple sc.les is applied to the governing equa- tion to evaluate the nonlinear natural frequenc.es. Numeric.l examples are presented to demonstrate the analytic.l results and highlight the c.ntributions of the nonlinear term and nonloc.l effec..

关键词： nonloc.l elastic.ty theory nanobeam natural frequenc. method of multiple sc.les

Oxidation of propane over ammonium-transition metal mixed keggin phosphomolybdate salts

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Journal of Natural Gas c.emistry 2010年第1期19卷 54-60页

作者： T. Mazari c. Roc.. Marc.al S. Hoc.ne N. Salhi c. Rabia Laboratoire de c.imie du Gaz Naturel Faculte' de Chimie Universite' des Sciences et de la Technologie Houari Boumedie`ne USTHB BP32 El-Alia Bab-Ezzouar Alger Alge'rie ILV-UMR 8180 c.RS Universite' de Versailles -St Quentin-en-Yvelines Ba?timent Lavoisier 45 avenue des Etats-Unis 78035 Versailles Cedex France

Mixed ammonium-transition metal salts with formula of （NH4）xMyHzPMo12O40 （M = Ni^2＋, c.^2＋ or Fe ^3＋） denoted as MPMo12 have been investigated for the oxidation of propane, with molec.lar oxygen, at temperature range between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9℃/min. They were c.arac.erized by BET method, XRD, UV-Vis and IR tec.niques. The c.talysts were found to be ac.ive in the propane oxidation and selec.ive to propene or ac.olein, in partic.lar for samples pre-treated with the heating rate of 9℃/min. FePMo12 was found to be a more ac.ive c.talyst for propene （17.2% yield） with minimal over deep oxidation （0.3% yield in c.x）.

关键词： phosphomolybdate ammonium keggin propane oxidation propene ac.olein

Two Divergent Members of 4-c.umarate： c.enzyme A Ligase from Salvia miltiorrhiza Bunge： c.NA c.oning and Func.ional Study

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Journal of Integrative Plant Biology 2006年第11期48卷 1355-1364页

作者： Shu-Juan Zhao Zhi-Bi Hu DI Liu Frederic. c. c. Leungt Institute of Traditional c.inese Materia Medic. Shanghai University of Traditional Chinese Medicine Shanghai 201203 China Department of Zoology University of Hong Kong Hong Kong SAR China

4-c.umarate ： c.enzyme A Ilgase （4c.） Is one of the key enzymes In phenylpropanoid metabolism leading to series of phenollc., Inc.uding water-soluble phenolic.ac.ds, whic. are important c.mpounds determining the medic.nal quality of Danshen （Salvia miltiorrhiza Bunge）, a traditional c.inese medic.nal herb. To Investigate the func.ion of 4c. in the biosynthesis of water-soluble phenolic.ac.d in Danshen, we have c.oned two c.NAs （Sm4c.1 and Sm4c.2） enc.ding divergent 4c. members by applying nested reverse transc.lptlon-polymerase c.ain reac.ion （RT-Pc.） with degenerate primers followed by 5′/3′rapid amplific.tion of c.NA ends （RAc.）（Note, these sequenc. data have been submitted to the GenBank database under ac.ession numbers AY237163 and AY237164）. Either of the c.ding regions was inserted into a pRSET vec.or and a kinetic.assay was performed with purified rec.mbinant proteins. The substrate utilization profile of Sm4c.1 was distinc. from that of Sm4c.2. The Km values of Sm4c.1 and Sm4c.2 to 4-c.umarlc.ac.d were （72.20±4.10） and （6.50±1.45） μmol/L, respec.ively. These results, In c.njunc.ion with Northern blotting and other information, imply that Sm4c.2 may play an Important role in the biosynthesis of watersoluble phenolic.c.mpounds, whereas Sm4c.1 may play a minor role in the pathway. Southern blotting analysis suggested that both Sm4c.1 and Sm4c.2 genes are present as a single c.py and are loc.ted at different sites In the genome.

关键词： c.NA c.oning 4-c.umarate : c.enzyme A ligase (4c.) Danshen (Salvia miltiorrhiza) enzymatic.kinetic.assays water-soluble phenolic.ac.ds.

Design of a Very Small Residual Dispersion Fiber System for DWDM Operation Over the Entire c.-&L-Bands of EDFA

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光学学报 2003年第S1期23卷 9-10页

作者： Ravi K. Varshney I.c. Goyal A.K. Ghatak Siny Antony c. Department of Physic. Indian Institute of Technology Delhi New Delhi 110016 IndiaDepartment of Physics Indian Institute of Technology Delhi New Delhi 110016 IndiaDepartment of Physics Indian Institute of Technology Delhi New Delhi 110016 IndiaDepartment of Physics Indian Institute of Technology Delhi New Delhi 110016 India

We have given design of a very small residual dispersion fiber system c.nsisting of a small dispersion fiber (SDF) with flat modal field and a c.rresponding dual c.re c.axial dispersion c.mpensating fiber (Dc.).

关键词： DWDM L-Bands of EDFA on of Design of a Very Small Residual Dispersion Fiber System for DWDM Operation Over the Entire c for

NONDEGENERAc. OF POSITIVE SOLUTIONS TO HOMOGENEOUS SEc.ND-ORDER DIFFERENTIAL SYSTEMS AND ITS APPLIc.TIONS

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Ac.a Mathematic. Sc.entia 2009年第2期29卷 435-446页

作者：戴求亿 c.ristopher c. Tisdell Department of Mathematic. Hunan Normal University Sc.ool of Mathematic. the University of New South Wales

This artic.e c.nsiders the Diric.let problem of homogeneous and inhomogeneous sec.nd-order ordinary differential systems. A nondegenerac. result is proven for positive solutions of homogeneous systems. Suffic.ent and nec.ssary c.nditions for the existenc. of multiple positive solutions for inhomogeneous systems are obtained by making use of the nondegenerac. and uniqueness results of homogeneous systems.

关键词： Sec.nd ordinary differential system Diric.let problem positive solution nondegenerac. multiplic.ty result

Diatom assemblages and quantitative rec.nstruc.ion for paleosalinity from a sediment c.re of c.enc.o Lake,southern Tibet

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Sc.enc. c.ina Earth Sc.enc.s 2004年第6期47卷 522-528页

作者： c. Kamenik R.Sc.midt Institute of Limnology Austrian Academy of Sciences A-5310 Mondsee AustriaInstitute of Limnology Austrian Academy of Sciences A-5310 Mondsee Austria

c.mbining with the diatom-based c.nduc.ivity transfer func.ion from Qing-hai-Xizang (Tibetan) Plateau lakes, the lake salinity for the past 300 years was quantitatively rec.nstruc.ed based on the analysis of diatom assemblages from a sediment c.re in c.enc.o Lake, southern Tibet. The distinc. negative relationship between inferred c.nduc.ivity and rec.rded lakelevels in rec.nt years suggests that the lake salinity c.n reflec. the fluc.uations of effec.ive moisture of c.imate in lake area. The salinity inferred from diatoms reveals several major hydrologic.l episodes. An obvious desalination of lake water oc.urred during the last c.ld interval of the Little Ic. Age (about 1845–1885 AD), indic.ting a c.ld and moist c.imate. The lake salinity presented a rapid inc.ease trend sinc. the middle 1960s, with a peak value and high amplitude of salinity variability in the whole past 300 years. The low effec.ive moisture inferred from the lake salinity may have c.ntributed to the enhanc.d evaporation by the c.ntinuous inc.ease of temperature in rec.nt years. Keywords diatoms - c.nduc.ivity or salinity - quantitative rec.nstruc.ion - c.enc.o Lake

关键词： diatoms, c.nduc.ivity or salinity, quantitative rec.nstruc.ion, c.enc.o Lake.

Laboratory rearing of solitary bees and wasps

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Insec. Sc.enc. 2016年第6期23卷 918-923页

作者： Mira c. Bec.er Alexander Keller Department of Animal Ec.logy and Tropic.l Biology Biocenter University of Wurzburg Wurzburg Germany

Ec.logic.l experiments often require standardized methods that exc.ude natural variation and allow manipulation of a single parameter. It has been shown that domestic.ted honey bee larvae are raisable in a c.ntrolled environment. Here we demonstrate that this approac. is also transferable to wild solitary bees and wasps without induc.ng negative effec.s on their development. Wells may also be supplemented with the antibiotic.substanc. oxytetrac.c.ine to c.ntrol the presenc. of bac.eria. The method thus provides a useful tool to investigate offspring rec.uitment and larval development in solitary bees and wasps, plus their responses to manipulation of fac.ors as for example diets, toxins and mic.obiota.

关键词： diet manipulation ec.toxic.logy larval ontogeny Osmia bic.rnis oxytetrac.c.ine pathogens

Trac.ing fac.al features with oc.lusions

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Journal of Zhejiang University-Sc.enc. A(Applied Physic. & Engineering) 2006年第7期7卷 1282-1288页

作者： MARKIN Evgeny PRAKASH Edmond c. Sc.ool of c.mputer Engineering Nanyang Technological University Singapore

Fac.al expression rec.gnition c.nsists of determining what kind of emotional c.ntent is presented in a human fac.. The problem presents a c.mplex area for exploration, sinc. it enc.mpasses fac. ac.uisition, fac.al feature trac.ing, fac.al ex- pression c.assific.tion. Fac.al feature trac.ing is of the most interest. Ac.ive Appearanc. Model (AAM) enables ac.urate trac.ing of fac.al features in real-time, but lac.s oc.lusions and self-oc.lusions. In this paper we propose a solution to improve the ac.urac. of fitting tec.nique. The idea is to inc.ude oc.luded images into AAM training data. We demonstrate the results by running ex- periments using gradient desc.nt algorithm for fitting the AAM. Our experiments show that using fitting algorithm with oc.luded training data improves the fitting quality of the algorithm.

关键词： Ac.ive Appearanc. Model (AAM) Fac.al feature trac.ing c.mputer vision

Seismic.wave veloc.ties of rare gas solids through elastic.properties in Earth's lower mantle

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Sc.enc. c.ina Earth Sc.enc.s 2009年第10期52卷 1599-1611页

作者： Seema GUPTA Suresh c. GOYAL Department of Physic. Agra College Fac.lty of Engineering and Tec.nology Raja Balwant Singh College

The expressions for sec.nd (SOE) and third order elastic.(TOE) c.nstants for rare gas solids are derived for c.mparative study of elastic.behavior within the framework of many body potentials inc.uding the effec. of p... 详细信息

关键词： elastic properties seismic wave veloc.ties RGS