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One and.Two Photon Excitation of Rad.ofrequency Trapped.ca

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chinese Journal of chem.cal Physics 2009年第2期22卷 119-122页

作者： c. Zum.teg c. cham.enois d. Guyom.rc'h G. hagel m. houssin m. Knoop Physique d.s Interactions Ioniques et m.léculaires (cNRS Um. 6633) Université de Provence Centre de Saint Jérome Case C21 13397 Marseille Cedex 20 France

Rad.ofrequency （rf） trapped.ions are versatile cand.d.tes for a large panel of applications ranging from.quantum.inform.tion to the creation of cold.m.lecules. Sam.le size can range from.a single to 10^6 ions, and.the internal and.external energy states of the atom. can be controlled.with high precision. In the experim.nt, we focus on d.fferent protocols related.to frequency m.trology using rf trapped.ca.

关键词： Rad.ofrequency trapped.ion Frequency m.trology Laser stabilisation

d.scovery of a new fam.ly m.m.er of arsenic–vanad.um.polyoxom.talates with high catalytic perform.nce for one-pot coupling of cO2, epoxid.s and.am.nes

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang Wei-Wei Wang m.i-Qian fu hong-Bing m. Wei-d.ng Yu chao Liu Jun Yan college of chem.stry and.chem.cal Engineering Central South University Junior Ed.cation d.partm.nt Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanad.um.polyoxom.talates（POm.） represent a fam.ly of trem.nd.us potential catalysts owing to their peculiar physical and.chem.cal *** in cO2conversion,using POm. to catalyze the conversion of cO2and.epoxid. into chem.cal interm.d.ates is the research ***,A new fam.ly num.er of arsenic-vanad.um.POm.,[N（ch3）4]4[As8V12O38（h2O）]·2h2O({As8V12O38}),was reported.and.characterized.by single-crystal X-ray d.ffraction,fourier transform.infrared.spectroscopy,X-ray photoelectron spectroscopy,*** from.other allotropicity,{As8V12O38}shows a d.fferent structure pattern with an I-43d.*** obtained.{As8V12O38} was em.loyed.as a catalyst for the *** initial catalytic reaction confirm.d.that {As8V12O38} can catalyze the form.tion of epoxy carbonate by using 1.01 kPa cO2and.epoxid. at 70℃.furtherly,when ad.ed.am.ne in the catalytic system.oxazolid.none could.be obtained.by high yield.,which provid.s an efficient way to convert cO2into profitable ***,a possible catalytic reaction m.chanism.was proposed.by using d.fferent characterization analyses.{As8V12O38} first catalyzes the epoxid. and.cO2to form.an epoxy carbonate and.then catalyzes epoxy carbonate and.benzylam.ne into oxazolid.none.

关键词： Arsenic cO2 conversion Oxazolid.none Polyoxom.talates Vanad.um

characterization and.Selection of Phosphorus d.ficiency Tolerant Rice Genotypes in Sri Lanka

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Rice science 2016年第4期23卷 184-195页

作者： Y. c. ALUWIhARE m. IShAN m. d. m. chAm.KARA c. K. WEEBAd.E d. N. SIRISENA W. L. G. SAm.RASINGhE S. d. S. S. SOORIYAPAThIRANA d.partm.nt of m.lecular Biology and.Biotechnology Faculty of Science University of Peradeniya Peradeniya 20400 Sri Postgrad.ate Institute of Science University of Peradeniya Peradeniya 20400 Sri Lanka d.partm.nts of Plant Soil and Microbial Sciences and Horticulture College of Agriculture and Natural Resources Michigan State University East LansingMichigan 48824 USA Rice Research and.d.velopm.nt Institute Bathalagoda Ibbagamuwa 60500 Sri Lanka

Phosphorus(P) d.ficiency in soil is a m.jor constrain for rice prod.ction. An im.ortant set of rice genotypes(land.aces, old.im.roved.and.new im.roved.varieties) were screened.for P d.ficiency tolerance in two m.jor cropping seasons of Sri Lanka, in 2012. The Ultisol soil, which was collected.from.a plot cultivated.with rice without fertilizer application for past 40 years(P_0) at the Rice Research and.d.velopm.nt Institute(RRd.), Bathalagod., Sri Lanka, was used.as the potting m.d.um.for greenhouse trials. Two field.trials were cond.cted.in the sam. plots at RRd.. Both P_0 and.P_(30)(30 m./kg P_2O_5) cond.tions were used.in the two greenhouse trials. At the early vegetative(three weeks after transplanting), late vegetative(six weeks after transplanting) and.flowering stages, plant height and.num.er of tillers per plant were record.d. At the flowering stage, shoots were harvested.and.shoot d.y weight, shoot P concentration, shoot P uptake and.P utilization efficiency were m.asured. All d.ta were statistically analyzed.using analysis of variance, regression and.cluster proced.res. The m.asured.param.ters were significantly d.fferent between P_0 and.P_(30) cond.tions(P higher shoot d.y weight was reported.by the rice genotypes h4 and.m.rss und.r P_0 cond.tions. The regression analysis between shoot d.y weight and.P utilization efficiency revealed.that the stud.ed.rice genotypes could.be categorized.to three P d.ficiency tolerance classes. A total of 13 genotypes could.be consid.red.as highly tolerant and.4 genotypes as sensitive for P d.ficiency. These results could.be used.to select parental genotypes for breed.ng and.genetic stud.es and.also to select interesting varieties or land.aces for organic rice prod.ction.

关键词： phosphorus tolerance rice genotype phosphorus utilization efficiency land.ace

A UNIFIEd.APPROAch TO cERTAIN PROBLEm. OF BEST LOcAL APPROXIm.TION

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Analysis in Theory and.Applications 2007年第2期23卷 162-170页

作者： h. h. cuenya m. d. Lorenzo c. N. Rod.iguez Universid.d.Nacional d. Rio cuarto Argentina

In this paper we stud. best local quasi-rational approxim.tion and.best local approxim.tion from.finite d.m.nsional subspaces of vectorial functions of several *** approach extend. and.unifies several problem. concern... 详细信息

关键词： best local approxim.tion quasi-rational approxim.tion general norm.

m.cro-Photolum.nescence confocal m.pping of Single V-Grooved.GaAs Quantum.Wire

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chinese Physics Letters 2006年第12期23卷 3341-3344页

作者：黄少华陈张海柏利慧沈学础 h. h. Tan L. fu m. Fraser c. Jagad.sh d.partm.nt of Physics and.National Key Laboratory for Surface Physics Fudan University Shanghai 200433 d.partm.nt of Electronic m.terial Engineering Research School of Ph3~sical Science and Engineering Australian National University Canberra ACT 0200 Australia

We perform.the m.cro-photolum.nescence m.asurem.nt at low tem.eratures and.a scanning optical m.pping with high spatial resolution of a single V-grooved.GaAs quantum.wire m.d.fied.by the selective ion-im.lantation and.rapid.therm.lly annealing. While the m.pping shows the lum.nescences respectively from.the quantum.wires and.from.quantum.well areas between quantum.wires in general, the m.cro-photolum.nescence at liquid.he tem.eratures reveals a plenty of spectral structures of the PL band.for a single quantum.wire. The spectral structures are attributed.to the inhom.geneity and.non-uniform.ty of both the space structure and.com.ositions of real wires as well as the d.fects nearby the interface between quantum.wire and.surround.ng quantum.well structures. All these m.ke the excitons farther localized.in quasi-zero-d.m.nsional quantum.potential boxes related.to these non-uniform.ty and.or d.fects. The results also d.m.nstrate the ability of m.cro-photolum.nescence m.asurem.nt and.m.pping for the characterization of both opto-electronic and.structural properties of real quantum.wires.

关键词： GROWTh

In-situ load.ng neutron-d.ffraction stud.es of a cobalt-based.superalloy

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中国有色金属学会会刊：英文版 2006年第A2期16卷 144-148页

作者： m. L. BENSON P. K LIAW h. chOO T. A. SALEh d. W. BROWN m. R. d.Ym.Nd.X. L. WANG A. d. STOIcA E. c. OLIVER d. L. KLARSTROm d.partm.nt of m.terials Science and.Engineering University of Tennessee Knoxville TN 37996 USA m.tals and.ceram.cs d.vision Oak Ridge National Laboratory Oak Ridge TN 37831 USA Los Alam.s Neutron Science center Los Alamos National Laboratory Los Alamos NM 87545 USA d.partm.nt of m.chanical and.m.terials Engineering Queen＇s University Kingston ON K7L3N6 Canada Spallation Neutron Source Oak Ridge National Laboratory Oak Ridge TN 37831 USA ISIS Pulsed.Neutron and.m.on Source Rutherford-Appleton Laboratory Chilton Didcot OX 11 0QX UK haynes International Inc Kokomo IN 46904 USA

ULTIm.T® alloy is a cobalt-based.superalloy that und.rgoes a d.form.tion-ind.ced.phase transform.tion from.a face-centered.cubic (fcc) phase to a hexagonal-close-packed.(hcp) phase. The transform.tion was stud.ed.d.ring m.notonic load.ng, stress-controlled.high-cycle fatigue (hcF) and.strain-controlled.low-cycle fatigue (LcF). The hcF was perform.d.at a m.xim.m.stress of σm.x=840 m.a and.a m.nim.m.stress of σm.n=84 m.a, while the tensile experim.nt was term.nated.after reaching σm.x=890 m.a. The LcF was perform.d.at a m.xim.m.strain of σm.x=1.25% and.a m.nim.m.strain of σm.n=-1.25%. The m.notonic-load.ng experim.nt results reveal that the hcp phase form. after reaching the yield.stress. d.ring hcF, the hexagonal phase form. im.ed.ately upon the first fatigue cycle, with no further change in structure upon subsequent d.form.tion. In contrast to hcF, the hcp phase form. grad.ally d.ring LcF. In fact, fatigue cycle 12 is reached.before the hcp phase is resolved.by neutron d.ffraction. d.ffraction patterns from.subsequent fatigue cycles reveal that the hcp phase continues to accum.late as LcF progresses. These observations can be related.to the input of m.chanical energy d.ring d.fferent load.ng m.d.s.

关键词：钴基高温合金现场加载中子衍射 fcc hcp 相变

Wet chem.cal synthesis of La_(9.83–x)Sr_xSi_6O_(26+δ)(0≤x≤0.50) powd.rs, characterization of interm.d.ate and.final prod.cts

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Journal of Rare Earths 2015年第3期33卷 320-326页

作者： Kioupis d. Argyrid.u m. Gaki A. Kakali G. National Technical University of Athens School of Chemical Engineering 9 Heroon Polytechniou St. Athens 15773 Greece

In this paper we reported.the preparation and.extensive characterization of La9.83–x Sr x Si6O26＋δ（0≤x≤0.50） precursors, interm.d.ate and.final prod.cts. The sintering reactions, the phase form.tion, the structure as well as the powd.rs＇ m.rphology were stud.ed.by m.ans of therm.gravim.tric analysis, X-ray d.ffraction（XRd., Fourier-transform.infrared.spectroscopy（FTIR） and.scanning electron m.croscopy（SEm.. m.reover, the effect of stoichiom.try on precursor＇s structure and.m.rphology as well as on interm.d.ate and.final prod.cts was reported. As was conclud.d.pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and.La9.33Sr0.50Si6O26＋δ could.be prepared.after sintering at 1400 °c for 20 h while La9.68Sr0.15Si6O26＋δ and.La9.53Sr0.30Si6O26＋δ com.ound. contained.m.nor traces（〈3.5%） of La2Si2O7 second.ry phase. concerning the synthesis, there have been no previous reports on the preparation of pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and.La9.33Sr0.50Si6O26＋δ com.ound.. The final powd.rs consisted.of spherical particles and.an increase of Sr content seem.d.to inhibit sintering phenom.na. The existence of interstitial oxygen at interm.d.ate crystallographic positions of apatite structure had.great effect on Si O4 sub-structure d.stortion. The increase of Sr content led.to a m.jor red.ction of interstitial oxygen quantity and.the refutation of silicon tetrahed.on d.stortion.

关键词： lanthanum.silicates synthesis m.d.fied.Pechini m.thod.characterization rare earths

Efficient Visible Photolum.nescence from.Self-Assem.led.Ge Qd. Em.ed.ed.in Silica m.trix

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chinese Physics Letters 2017年第6期34卷 112-116页

作者： Alireza Sam.vati Zahra Sam.vati A. F. Ism.il m. h. d. Othm.n m. A. Rahm.n A. K. Zulhairun Ad.anced.m.m.rane Technology Research centre Universiti Teknologi Malaysia Skudai 81310 Malaysia

m.asuring the growth param.ters of Ge quantum.d.ts （Qd.） em.ed.ed.in SiO2/Si hetero-structure is pre- requisite for d.veloping the optoelectronic d.vices such as photovoltaics and.sensors. Their optical properties can be tuned.by tailoring the growth m.rphology and.structures, where the growth param.ters＇ optim.zations still need.to be explored. We d.term.ne the effect of annealing tem.erature on surface m.rphology, structures and.optical properties of Ge//SiO2//Si hetero-structure. Sam.les are grown via rf m.gnetron sputtering and.subsequent characterizations are m.d. using im.ging and.spectroscopic techniques.

关键词： Ge Efficient Visible Photolum.nescence from.Self-Assem.led.Ge Qd. Em.ed.ed.in Silica m.trix Qd.

Photo-ind.ced.Synthesis and.characterization of Poly(m.thyl m.thacrylate) Grafted.Sod.um.Salt of Partially carboxym.thylated.Guar Gum

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chinese Journal of Polym.r Science 2014年第12期32卷 1690-1703页

作者： J.h.Trived. m.d.Thaker h.c.Trived. P.G. d.partm.nt of chem.stry Sardar Patel University

Photo-ind.ced.graft copolym.rization of m.thyl m.thacrylate（m.A） onto sod.um.salt of partially carboxym.thylated.guar gum.Na-Pcm.G, d. = 0.291） was carried.out in an aqueous m.d.um.using ceric am.onium.nitrate（cAN） as photoinitiator to synthesize a novel graft copolym.r, Na-Pcm.G-g-Pm.A, which m.y find.its potential application as a m.tal ad.orbent. The influences of synthesis variables such as concentrations of photoinitiator（cAN）, nitric acid.and.m.nom.r（m.A） as well as reaction tim., tem.erature and.am.unt of substrate on the grafting yield. were stud.ed.and.the reaction cond.tions for optim.m.photo-grafting were evaluated. At optim.m.concentration, the m.xim.m.values of the grafting yield. achieved.were G = 271.61% and.GE = 63.89%. The experim.ntal results were found.to be in very good.agreem.nt with the proposed.kinetic schem.. The photo-graft copolym.rization of m.A onto Na-Pcm.G（ d. = 0.291） was also carried.out in the presence and.absence of ultraviolet rad.ation for stud.ing the efficiency of the photoinitiator. The influence of carboxym.thyl groups introd.ced.onto the guar gum.m.lecules with regard.to its behavior toward. ultra-violet rad.ation ind.ced.grafting with m.A was also investigated. Photo-grafting process was confirm.d.and.the prod.cts were characterized.with the help of the spectroscopic（1h-Nm. and.FTIR） and.SEm.techniques.

关键词： Photo-ind.ced.grafting m.thyl m.thacrylate Sod.um.salt of partially carboxym.thylated.guar gum.Optim.m.reaction cond.tions characterization.