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Nonlinear.vibr.tions of nano-beams accounting for.nonlocal effect using a multiple scale method

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Science China(Technological Sciences) 2009年第3期52卷 617-621页

作者： C. w. LIM Depar.ment of Building and Constr.ction City University of Hong Kong

The nonlinear.fr.e tr.nsver.e vibr.tions of a nano-beam on simple suppor.s ar. investigated based on nonlocal elasticity theor.. The gover.ing equation is pr.posed by consider.ng geometr.c nonlinear.ty due to finite str.tching of the beam. The method of multiple scales is applied to the gover.ing equa- tion to evaluate the nonlinear.natur.l fr.quencies. Numer.cal examples ar. pr.sented to demonstr.te the analytical r.sults and highlight the contr.butions of the nonlinear.ter. and nonlocal effect.

关键词： nonlocal elasticity theor. nanobeam natur.l fr.quency method of multiple scales

Effect of Added Cu(OTf)2on the Cu(OTf)2(Py)4-Mediated r.diofluor.nation of Benzoyl and Phthaloylglycinates

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Natur.l Science 2018年第3期10卷 125-133页

作者： David w. Blevins Geor.e w. Kabalka Dustin r. Osbor.e Mur.hy r. Akula Depar.ment of r.diology University of Tennessee Medical Center Knoxville Tennessee USA Depar.ment of Chemistr. University of Tennessee Knoxville Tennessee USA

Cu(OTf)2(Py)4 mediated r.diofluor.nation of the bor.nate ester. of ethyl benzoyl and phthaloylglycinates (11 and 16) using 10 mol% of the copper.complex follow.ng the liter.tur. pr.cedur. did not pr.vide the fluor.nated pr.ducts. How.ver. the addition of Cu(OTf)2r.sulted in the r.dio-fluor.nation of the bor.nate ester. 11 and 16 to obtain ethyl 4-[18F]fluor.benzoyl glycinate, 17, (48%) and ethyl 3-[18F]phthaloylglycinate (41%) r.spectively.

关键词： Glycinates Bor.nate Ester. Gor.os-Phos r.diofluor.nation Copper Tr.flate

Functional Char.cter.zation and r.Ai-Mediated Suppr.ssion r.veals r.les for.Hexose Tr.nspor.er. in Sugar.Accumulation by Tomato Fr.it

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Molecular.Plant 2010年第6期3卷 1049-1063页

作者： David w. McCur.y Stephen Dibley r.cky Cahyanegar. Antony Mar.in John w. Patr.ck School of Envir.nmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia

Hexoses accumulate to high concentr.tions （-200 mM） in stor.ge par.nchyma cells of tomato fr.it. Hexoses ar. sour.ed fr.m the fr.it apoplasm as hydr.lysis pr.ducts of phloem-impor.ed sucr.se. Thr.e hexose tr.nspor.er. （LeHT1, LeHT2, LeHT3）, expr.ssed in fr.it stor.ge par.nchyma ceils, may contr.bute to hexose uptake by these cells. An analysis of their.full-length sequences demonstr.ted that all thr.e tr.nspor.er. belong to the STP subfamily of monosacchar.de tr.nspor.er. that localize to plasma membr.nes. Heter.logous expr.ssion of LeHT1 （and pr.viously LeHT2, Gear.et al., 2000）, but not LeHT3, r.scued a hexose tr.nspor.impair.d yeast mutant w.en r.ised on glucose or.fr.ctose as the sole car.on sour.e. Biochemically, LeHT1, similar.y to LeHT2, exhibited tr.nspor. pr.per.ies consistent w.th a high- affinity glucose/H^＋ sympor.er. Significantly, LeHT1 and LeHT2 also functioned as low.affinity fr.ctose/H^＋ sympor.er. w.th appar.nt Km values commensur.te w.th those of fr.it tissues. A substantial r.duction （80-90%） in fr.it expr.ssion levels of all LeHT genes by r.Ai-mediated knockdow. caused a 55% decr.ase in fr.it hexose accumulation. In contr.st, photoassimilate pr.duction by sour.e leaves and phloem tr.nspor. capacity to fr.it w.r. unaffected by tr.nspor.er.knockdow.. Collectively, these findings demonstr.te that LeHTs play key r.les in dr.ving accumulation of hexoses into stor.ge par.nchyma cells dur.ng tomato fr.it development.

关键词： Fr.it hexose tr.nspor.er sink tomato r.Ai.

Molecular.Mechanisms r.gulating r.pid Str.ss Signaling Netw.r.s in Ar.bidopsis

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Jour.al of Integr.tive Plant Biology 2010年第4期52卷 354-359页

作者： Justin w. w.lley Katayoon Dehesh Depar.ment of Plant Biology University of California Division of Biological Sciences University of California

As sessile or.anisms plants must r.nmental conditions. To sur.ive cope w.th ever.changing enviplants have evolved elabor.te mechanisms to per.eive and r.pidly r.spond to a diver.e r.nge of abiotic and biotic str.sses. Centr.l to this r.sponse is the ability to modulate gene expr.ssion at both the tr.nscr.ptional and posttr.nscr.ptional levels. This r.view.w.ll focus on r.cent pr.gr.ss that has been made tow.r.s under.tanding the r.pid r.pr.gr.mming of the tr.nscr.ptome that occur. in r.sponse to str.ss as w.ll as emer.ing mechanisms under.inning the r.pr.gr.mming of gene expr.ssion in r.sponse to str.ss,

关键词： Molecular.Mechanisms r.gulating r.pid Str.ss Signaling Netw.r.s in Ar.bidopsis CAF

Compar.son betw.en the electr.cal r.sistance and the shear. str.ngth of br.zed cemented car.ides

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China w.lding 2015年第2期24卷 1-5页

作者： w. Tillmann N. Siever. D. Schnee r. Zielke L. w.jar.ki H. r.es F. Ozkan Institute of Mater.als Engineer.ng Technical University ofDortmund Leonard-Euler-Str. 2 44227Dortmund Germany. Umicor. AG & Co. KG Business Unit TechnicalMaterials Rodenbacher Chaussee 4 63457

Br.zing is a suitable technology to join differ.nt mater.als such as cemented car.ides and steel. Even though this technology has been investigated for.many year., insufficient joints can occur.easily, as the br.zing pr.cess is ver. sensitive concer.ing the handling par.meter.. Defects such as voids and cr.cks ar. har. to detect by commonly used visual inspection methods. Other.nondestr.ctive methods such as r.diogr.phy or.ultr.sonic testing ar. usually not economical for.the examination of these joints. Studies pr.ved that the electr.cal r.sistance has the potential to ser.e as an effective alter.ative for.the evaluation of br.zed joints. In this study, the author. have compar.d the electr.cal r.sistance and the shear.str.ngth. For.this, cemented car.ides w.r. br.zed to steel by means of induction heating at an ambient atmospher.. A silver.based filler.metal （ Br.zeTec 4900 / Ag 449 ） and a flux （ Br.zeTec spezial h / FH12） w.r. selected to enable the br.zing pr.cess. The br.zing time and the temper.tur. w.r. var.ed in or.er.to pr.duce differ.nt joint qualities. After.br.zing, the r.sistance w.s measur.d on each joint w.th the 4-point pr.be method to facilitate a high accur.cy. The r.sults under.ine the possibility to use electr.cal r.sistance measur.ments as an effective tool for.a quality contr.l of br.zed joints.

关键词： br.zing cemented car.ides electr.cal r.sistance nondestr.ctive testing the br.zing pr.cess and can led to an unpr.dictable failur.

Nucleosynthesis in ther.onuclear.super.ovae

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Fr.ntier. of physics 2013年第2期8卷 199-216页

作者： Claudia Tr.vaglio w. r.phael Hix fNAF-Astr.physical Obser.ator. Tur.n Strada Osservagorio 20 10025 Pino Torinese Italy Physics Division Oak Ridge National Laboratory. Oak RidgeUSA TN 37830 Depar.ment of Physics and Astr.nomy University of Tennessee KnoxvilleUSA TN 37996

w. r.view.our.under.tanding of the nucleosynthesis that occur. in ther.onuclear.super.ovae and their.contr.bution to Galactic Chemical evolution. w. discuss the pr.spects to impr.ve the modeling of the nucleosynthesis... 详细信息

关键词： super.ovae nuclear.r.actions explosive nucleosynthesis stellar.spectr.,hydr.dynamics chemical evolution

r.cover. of Nitr.gen and Phosphor.us as Str.vite Fr.m Sw.ne w.ste Biogas Digester.Effluent

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Biomedical and Envir.nmental Sciences 2007年第5期20卷 343-350页

作者： P. w. ANTON PEr.r. College of Envir.nmental and r.sour.e Sciences Zhejiang University

Objective To investigate the feasibility of nitr.gen and phosphor.s r.cover. fr.m sw.ne w.ste biogas digester.effluent and the effects of pH and NH4^＋： Mg2^＋： PO4^3- molar.r.tio on its pr.cipitation. Methods Pr.cipitation exper.ments w.th sw.ne w.ste biogas digester.effluent w.r. conducted at pH 7.5, 8.0, 8.5, and 9.0 together.w.th NH4^＋： Mg^2＋： PO4^3- molar.r.tios 1： 0.2： 0.08, 1： 1： 1, and 1： 1.5： 1.5. Chemical and X-r.y diffr.ction （Xr.） analysis w.r. done to deter.ine the composition of the pr.cipitate. r.sults The highest r.moval and r.cover. of NH4^＋ and PO4^3- w.r. achieved at pH 9.0 in each exper.ment. The elevation of pH to 9.0 alone could decr.ase the initial PO4^3- concentr.tion fr.m 42 mg L^-1 to 4.7 mg L-1 and 89.2% PO4^3- r.cover. w.s achieved. The pH-molar.r.tio combination 9.0-1： 1.5： 1.5 effected 76.5% NH4^＋ and 68.5% PO4^3- r.cover.. The molar.r.tio of 1： 1： 1 together.w.th pH elevation to 9.0 w.s deter.ined to be the optimum combination for.both NH4＋ and PO4^3- r.moval as it r.cover.d over.70% and 97% of the initial NH4^＋ and PO4^3-, r.spectively. Conclusions Nitr.gen and phosphor.s can be r.cover.d fr.m biogas digester.effluent as str.vite.

关键词： Phosphate r.cover. Ammonium nitr.gen r.cover. Biogas Str.vite Sw.ne w.ste

An active set algor.thm for.nonlinear.optimization w.th polyhedr.l constr.ints

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Science China Mathematics 2016年第8期59卷 1525-1542页

作者： HAGEr.w.lliam w. ZHANG Hongchao Depar.ment of Mathematics University of FloridaGainesvilleFL 32611-8105USA Depar.ment of Mathematics Louisiana State UniversityBaton RougeLA 70803-4918USA

A polyhedr.l active set algor.thm PASA is developed for.solving a nonlinear.optimization pr.blem w.ose feasible set is a polyhedr.n. Phase one of the algor.thm is the gr.dient pr.jection method, w.ile phase tw. is any algor.thm for.solving a linear.y constr.ined optimization pr.blem. r.les ar. pr.vided for.br.nching betw.en the tw. phases. Global conver.ence to a stationar. point is established, w.ile asymptotically PASA per.or.s only phase tw. w.en either.a nondegener.cy assumption holds, or.the active constr.ints ar. linear.y independent and a str.ng second-or.er.sufficient optimality condition holds.

关键词： polyhedr.l constr.ined optimization active set algor.thm PASA gr.dient pr.jection algor.thm local and global conver.ence

Mass attenuation coefficient of olive peat mater.al for.absor.ing gamma r.y ener.y

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Nuclear.Science and Techniques 2019年第7期30卷 27-35页

作者： Mohammad w. Mar.shdeh Hanan Saleh Depar.ment of Physics College of Sciences Imam Mohammad Ibn Saud Islamic University (IMSIU) P.O. Box 90950 Riyadh 11623 Saudi Arabia Depar.ment of r.diogr.phy Princess Aisha Bint Al-Hussein College of Nursing and Health Sciences Al-Hussein Bin Talal University P.O. Box 20 Ma’an Jordan

The mass attenuation coefficients (l/q) of a natur.l mater.al, i.e., olive peat, w.r. measur.d at photon ener.ies of 0.059, 0.356, 0.662, 1.17, and 1.332 MeV and compar.d w.th those of concr.te and Pb. The exper.mental samples w.r. ir.adiated w.th 214Am, 133Ba, 137Cs, and 60Co point sour.es using a tr.nsmission ar.angement. The olive peat samples w.r. obtained fr.m differ.nt ar.as in Jor.an, namely Mafr.q (sample M), Ker.k (sample K), Ajloun (sample A), and Ir.id (sample I), and photon ener.ies w.r. measur.d using a NaI(Tl) scintillation detector.w.th an ener.y r.solution of 7.6% at 662 keV. The differ.nces in the l/q of olive peat samples and the calculated l/q of concr.te w.r. consistently w.thin 0.7% at photon ener.ies of 0.356–1.332 MeV. This finding indicates that olive peat can be used in r.diation applications in the field of medical physics. Finally, the half-value layer.(HVL) of the exper.mental samples w.s measur.d, and r.sults w.r. compar.d w.th those of concr.te and Pb. Pb and concr.te exhibited minimal HVL values due to their.high density, and the HVL of olive peat r.vealed low.r.shielding effectiveness than that of concr.te.

关键词： Olive peat Attenuation coefficient Halfvalue layer Gamma r.y