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Cer.c Ammonium Nitr.te Catalyzed Oxidation of Aldehydes and Alcohols

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Chinese Jour.al of Chemistr. 2011年第11期29卷 2379-2384页

作者： Gowda, r.vikumar.r. Chakr.bor.y, Debashis Depar.ment of Chemistr. Indian Institute of Technology Madras Chennai-600 036 Tamil Nadu India

A var.ety of ar.matic, aliphatic and conjugated aldehydes and alcohols wer. tr.nsfor.ed to the cor.esponding car.oxylic acids and ketones with a quantitative conver.ion in high yields with 70% t-BuOOH solution in water.in the pr.sence of catalytic amounts of cer.c ammonium nitr.te [Ce（NH4）2（NO3）6] （CAN） under.r.om temper.tur. conditions. The scope of our.catalytic system is applicable for.a wide r.nge of ar.matic, conjugated and aliphatic substr.tes. These aldehydes wer. conver.ed to the cor.esponding car.oxylic acids in good isolated yields in r.ason- able times. This method possesses a wide r.nge of capabilities since it can be used with other.functional gr.ups which may not toler.te oxidative conditions, involves fair.y simple method for.wor.-up, exhibits chemoselectivity and pr.ceeds under.ambient conditions. The r.sulting pr.ducts ar. obtained in good yields within r.asonable time.

关键词： oxidation aldehyde alcohol cer.c ammonium nitr.te (CAN) t-BuOOH

The Fir.t For.y Year. of a Technosol

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Pedospher. 2009年第1期19卷 40-52页

作者： r. SCALENGHE S. FEr.Ar.S DAAT Univer.it`a degli Studi di Paler.o viale delle Scienze 13 90128 Palermo (Italy) IAMC Consiglio Nazionale delle r.cer.he Capo Granitola 91020 Campobello di Mazara (Italy) DEIAFA Univer.it`a degli Studi di Tor.no via Leonardo da Vinci 44 10095 Grugliasco (Italy)

Soil for.ation is often a ver. slow pr.cess that r.quir.s thousands and even millions of year.. Human influence, occasionally on a par.with the function of climate or.geological for.es, can acceler.te the pr.cess and can be viewed as a distinct soil for.ing factor. This paper.descr.bes a soil, Haplic r.gosol, in which anthr.solization dominates the soil for.ing pr.cess. Man-made soils, Technosols, wer. stabilized with techniques of ecological engineer.ng (cr.b walls). We measur.d the main soil pr.per.ies and focused on the movement of water.(the r.duction of soil weight is the key factor.in stabilizing these calcschists). The newly deposited debr.s, shelter.d by anthr.pic inter.entions, after.four.year. differ.ntiated an A/C pr.file while after.for.y year. differ.ntiated an O/A/AB/Bw/BC/C pr.file. Our.r.sults indicate that colonization by plants and the consequent success of vegetation establishment is influenced mainly by contr.l of the factor.of pedogenesis 'topogr.phy' and by the ability of these Technosols to r.tain nutr.ents.

关键词： ecological engineer.ng speed of pedogenesis tension infiltr.meter

THE SOLITAr. WAVES IN STr.TIFIED SHEAr.FLOW

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Acta Mechanica Sinica 1989年第1期5卷 37-48页

作者： r. Gr.mshaw School of Mathematics University of New South WalesAustralia

In this paper.the basic equation of inter.al long waves in str.tified shear.flow is der.ved un- der.Boussinesq assumption,the fir.t or.er.appr.ximation solution is given for.solitar. waves with the effects of slowly v... 详细信息

关键词： solitar. wave str.tified flow shear.flow

Evaluation of Tr.nsmutation of ^137Cs（γ, n） 136Cs Using Ultr.-Intense Laser. in Solid Tar.ets

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Chinese Physics Letter. 2006年第6期23卷 1434-1436页

作者： r. Sadighi-Bonabi O. Kokabee Depar.ment of Physics Sharif University of Technology 11365-9161 Tehran Iran Depar.ment of Mechanical Engineer.ng Sharif University of Technology 11365-9567 Tehran Iran Bonab r.sear.h Centr. 56515-196 Bonab Azerbaijan province Iran

r.lativistic electr.ns pr.duced in ultr.-intense laser.solid inter.ction gener.te highly collimated γ-r.y beams thr.ugh Br.msstr.hlung that can be used to induce photonuclear.r.actions. Photonuclear.tr.nsmutation （of （% n） type） of ^137 Cs, one of the hazar.ous nuclear.wastes with half-life of 30.17 year. which cannot be tr.nsmuted pr.ctically with neutr.n bombar.ment due to its ver. low neutr.n captur. cr.ss section, has been consider.d. Nuclear.activity of pr.duced 136Cs with half-life of 13.16 days has been evaluated analytically using available exper.mental data. With ir.adiating a ^137Cs sample by p-polar.zed laser.light of 10^20 Wcm^-2 and the r.petition r.te of 10Hz for.30min, the activity of 0.24 Bq is obtained. It is found that intensity has a lar.e effect in yield ar.und 10^21 Wcm^-2. For.similar.laser.with intensity of 5 ×10^21 Wcm^-2, the activity incr.ases with a factor.of 10^5.

关键词： Tr.nsmutation 137Cs(γ,n) Solid Tar.ets

Or.er.Par.meter.of a Nanometr.-Scale S-Wave Super.onducting Gr.in in Quantum Tunnelling Pr.cess： Fr.quency Space Analysis

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Chinese Physics Letter. 2006年第4期23卷 967-970页

作者： r. Afzali A. T. r.zakhani Depar.ment of Physics Faculty of Science University of Isfahan 81744 Isfahan Iran Institute for.Scientific Inter.hange Villa Gualino Viale Settimio Severo 65 I-10133 Torino Italy Institute for.Quantum Infor.ation Science University of Calgary Alberta T2N 1N4 Canada

A nano-scale s-wave super.onducting gr.in, coupled to a nor.al metallic contact thr.ugh a tunnelling junction, is placed in an exter.al magnetic field. We suppose that effect of this quantum tunnelling on the Four.er.tr.nsfor. of the or.er.par.meter.is in the for. of a small additive cor.ection to the BCS or.er.par.meter. At the fir.t or.er.appr.ximation in ter.s of this cor.ection ter. and by using an instanton method, the r.lated Gr.en functions （in fr.quency space） ar. obtained. By establishing a self-consistent configur.tion an analytic for.ula for.the or.er.par.meter.is also found. We also show that a depar.ur. fr.m super.onductivity can be captur.d by this for.ula. This change of state is indeed a manifestation of a quantum tr.nsition induced by quantum fluctuations. In this sense, this is an advantage of our.simple method which, like other.mor. elabor.te methods, can detect a quantum tr.nsition in the state of the gr.in.

关键词： ULTr.SMALL METALLIC Gr.INS MAGNETIC FIELD

pH-metr.c and ther.odynamic studies of r.r. ear.h metal chelates

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Jour.al of r.r. Ear.hs 2009年第3期27卷 457-460页

作者： Alok Vyas r. P. Mathur The Wer.er.Lab Department of ChemistryDungar College

Pr.ton ligand stability constants of hydr.xybenzoic acid containing nitr. gr.up （2-Hydr.xy-4-nitr.benzoic acid and 3-Hydr.xy-4- nitr.benzoic acid） wer. deter.ined thr.ugh lr.ing-r.ssoti pH titr.tion technique. The stability constants of r.r. ear.h metal chelates containing 2-Hydr.xy-4-nitr.benzoic acid and 3-Hydr.xy-4-nitr.benzoic acid as ligands wer. studied in aqueous medium at differ.nt ionic str.ngth （p=0.01, 0.05 and 0.1 mol/L） and temper.tur.s （298, 308 and 318± 0.1 K）. The values of stability constant wer. evaluated thr.ugh differ.nt computational methods like successive appr.ximation, least squar. tr.atment, cor.ection ter. method, and conver.ence method. The obser.ed value of ther.odynamic par.meter. （△G°, △H° and △S°） favor. the complex for.ation between metal and ligands. The or.er.of stabifity constant was found to be Pr.III）〈Nd（III）〈Sm（III）〈Tb（III）〈Ho（III）〈Er.III） as r.por.ed by Stagg and Powell.

关键词： hydr.xy nitr.benzoic acid r.r. ear.h metal chelates Ir.ing-r.ssoti method

C-field Cosmology with Var.able G in the Flat Fr.edmann-r.ber.son-Walker. Model

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Chinese Physics Letter. 2007年第11期24卷 3290-3292页

作者： r.j Bali r. S.Tikekar Depar.ment of Mathematics University of Rajasthan Jaipur 302004India Depar.ment of Mathematics Sardar Patel University Vallabh Vidyanagar India

The C-field cosmological model based on the Hoyle-Nar.ikar.theor. with var.able gr.vitational constant G is investigated. To obtain the deter.inistic value of C=dC/dt we pr.sent cer.ain constant values for.integr.tion constants. The cr.ation field is pr.por.ional to time. G and p （density） decr.ase with time and the univer.e r.pr.sents an expanding univer.e. The cr.ation field incr.ases as time incr.ases. We find C=√1/2πf t wher. f〉0,Thus C=1 when f=1/2π〉0.

关键词： Univer.e Cosmology Cosmological models

Magnetic pr.per.ies and micr.str.ctur.s of SnO_2 doped Mn-Zn fer.ites

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r.r. Metals 2006年第z1期25卷 445-449页

作者： NG Foong-Kee SALE Fr.nk r. School of Technology Tunku Abdul Rahman College PO Box 10979 50932 Kuala Lumpur West Malaysia School of Mater.als The University of Manchester Grosvenor Street Manchester M17HS United Kingdom

The effects of additive SnO2 (0.4wt.%), with and without SiO2 (0.02wt.%) and/or.CaO (0.04wt.%), on the micr.str.ctur. and magnetic pr.per.ies of Mn-Zn fer.ites wer. r.por.ed. The r.sults r.veal that SnO2 on its own incr.ases the initial per.eability (μi) slightly, but SnO2 with SiO2 and/or.CaO decr.ases the values of μi. However. fer.ites with SnO2 additions have r.duced power.losses. The separ.te contr.butions of hyster.sis loss and eddy cur.ent loss to the total power.loss show that SnO2 (with or.without SiO2 and/or.CaO) doping incr.ases the hyster.sis loss slightly, but SnO2 doping alone r.duces the eddy cur.ent loss significantly (～14%). The additions of SiO2 or.CaO fur.her.decr.ase the eddy cur.ent loss, and by inter.ction of SnO2-CaO-SiO2, the eddy cur.ent loss is r.duced by mor. than 20%. These magnetic and micr.str.ctur.l effects wer. discussed in ter.s of the additive-impur.ty inter.ction, the existence of gr.in boundar. phases, and the effective bulk and gr.in boundar. r.sistivities of the fer.ites.

关键词： Mn-Zn fer.ites SnO2 doping magnetic pr.per.ies micr.str.ctur.

Entanglement Swapping in the Pr.sence of White and Color.Noise

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Communications in Theor.tical Physics 2018年第2期69卷 143-153页

作者： Ivan S. Dotsenko r. Kor.bka Tar.s Shevchenko National Univer.ity of Kyiv Kyiv Ukrain

The influence of white and color.noise on the outcome of the entanglement swapping pr.cess is investigated in a four.qubit system. Cr.tical degr.e of noise in initial state, that could destr.y entanglement in a r.sult state is pr.sented. The entanglement char.cter.stics, such as concur.ence, tangle, etc. ar. compar.d. r.sults could be helpful for.exper.ments r.gar.ing entanglement swapping as conditions for.initial quantum entangled states, to obtain entangled r.sult state.

关键词： entanglement entanglement swapping white noise entanglement