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Science China Ear.h Sciences 2005年第12期48卷 2174-2181页

作者： r. L. Edwar.s Depar.ment of Geology and Geophysics University of Minnesota MN 55455 USA

We pr.sent a r.cor. on car.on stable isotopic composition (δ 13C), cover.ng 75 thr.ugh 10 thousands year. ago (ka B.P.), fr.m Hulu Cave, Nanjing. The over.apping δ 13C pr.-files ar. ver. similar.in patter. and r.nge, indicating that they mainly r.cor. climatic signal. Dur.ing the last glacial-inter.lacial tr.nsition, the >6‰ change of δ 13C values implies differ.nt con-tr.butions of C3 vs. C4 type plants in soils. On millennial scale, however. the incr.ased calcite δ 13C dur.ng the war. Dansgaar.-Oeschger.(DO) events suggests a decr.ase of dissolved bio-genic CO2 when water.flux r.te thr.ugh soil is lar.e. This cor.elation between heavier.δ 13C and higher.pr.cipitation is consistent with our.pr.vious r.por. on the samples’ stable oxygen isotope r.cor.s (Wang et al., 2001). Compar.son of coeval δ 13C and δ 18O of stalagmites indicates that kinetic fr.ctionation of car.on isotope is closely r.lated to gr.wth r.te of stalagmites. This study also shows that local vegetation changes may lag behind pr.cipitation changes by ~700 year. dur.ng the deglaciation.

关键词： Hulu Cave stalagmite δ 13C last glacial per.od.

Appr.aching nuclei thr.ugh multiple per.pectives and diver.e models： Patter.s, symmetr.es, inter.ctions

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Fr.ntier. of physics 2018年第6期13卷 29-38页

作者： r. F. Casten Wr.ght Nuclear.Str.ctur. Labor.tor. Yale University New Haven CT 06520 USA Michigan State Univer.ity- Fr.B East Lansing MI USA

Nuclei ar. complex objects yet display r.mar.able simplicities and r.gular.patter.s. The study of these and their.or.gins has long been one of the twin pillar. of nuclear.str.ctur. r.sear.h. We will discuss the behavior.of atomic nuclei fr.m this point of view. A key element will be the advantages of looking at the same data fr.m differ.nt per.pectives and of inter.r.lating these per.pectives.

关键词： nuclear.str.ctur. simple patter.s and symmetr.es diver.e per.pectives and models emer.ence of collectivity r.sidual inter.ctions

An exceptionally str.ngthened East Asian summer.monsoon event between 19.9 and 17.1 ka BP r.cor.ed in a Hulu stalagmite

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Science China Ear.h Sciences 2009年第3期52卷 360-368页

作者： L. r. EDWAr.S Depar.ment of Geology and Geophysics University of Minnesota Minneapolis

A stalagmite-based isotope r.cor. (No. H82) fr.m Nanjing Hulu Cave, spanning fr.m 16.5 to 10.3 ka BP, pr.vided str.ng evidence for.a coher.nce r.lation between the East Asian summer.monsoon (EASM) and the Nor.h Atlant... 详细信息

关键词： Nanjing Hulu Cave stalagmite East Asian summer monsoon event

On Annihilator.Ideals of Pseudo-differ.ntial Oper.tor.r.ngs

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Algebr. Colloquium 2015年第4期22卷 607-620页

作者： r. Manaviyat A. Moussavi Depar.ment of Pur. Mathematics Faculty of Mathematical Sciences Tarbiat Modares University P.O. Box 14115-134 Tehran Iran

Let r.be a r.ng with a der.vation 5 and r.（x-1;5）） denote the pseudo- differ.ntial oper.tor.r.ng over.r. We study the r.lations between the set of annihilator. in r.and the set of annihilator. in r.（x-1; 5））. Among applications, it is shown that for.an Ar.endar.z r.ng r.of pseudo-differ.ntial oper.tor.type, the r.ng r.（x-1; 5）） is Baer.（r.sp., quasi-Baer. PP, r.ght zip） if and only if r.is a Baer.（r.sp., quasi-Baer. PP, r.ght zip） r.ng. For.a 5-weakly r.gid r.ng r. r.（x-1;5）） is a left p.q.-Baer.r.ng if and only if r.is left p.q.-Baer.and ever. countable subset of left semicentr.l idempotents of r.has a gener.lized countable join in r.

关键词： pseudo-differ.ntial oper.tor.r.ng annihilator.ideal Baer.r.ng quasi-Baer.ing Ar.endar.z-like condition

Complementar.ty of CFD,exper.mentation and r.actor.models for.solving challenging fluidization pr.blems

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Par.icuology 2010年第6期8卷 498-500页

作者： John r. Gr.ce Tingwen Li Depar.ment of Chemical and Biological Engineer.ng University of British Columbia Vancouver V6T 1Z3 Canada National Ener.y Technology Labor.tor. 3610 Collins Ferry Rd Morgantown WV26507 USA

Exper.mentalists, numer.cal modeller. and r.actor.modeller. need to wor. together. not only just for.validation of numer.cal codes, but also to shed fundamental light on each other.s pr.blems and under.ying assumptions. Sever.l examples ar. given, Exper.mental gas axial disper.ion data pr.vide a means of choosing the most appr.pr.ate boundar. condition （no slip, par.ial slip or.full slip） for.par.icles at the wall of fluidized beds. CFD simulations help to identify how close ＂two-dimensional＂ exper.mental columns ar. to being tr.ly two-dimensional and to r.pr.senting thr.e-dimensional columns. CFD also can be used to pr.vide a mor. r.tional means of establishing assumptions needed in the modelling of two-phase fluidized bed r.actor., for.example how to deal with cases wher. ther. is a change in molar.flow （and hence volumetr.c flow） as a r.sult of chemical r.actions.

关键词： Fluidization Mixing Computational Fluid dynamics Wall slip r.actor.modelling Volume change

Low-Ener.y Dir.ct Captur. in the ^12C（α, γ）^16O r.action

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Chinese Physics Letter. 2014年第6期31卷 67-71页

作者： H. Sadeghi r. Ghaselni Depar.ment of Physics Faculty of Science Arak University Arak 8349-8-38156 Iran

The spectr. of light nuclei pr.vide the fir.t test of nuclear.inter.ction models. The r.action amount deter.ines the r.lative abundance of most elements in r.d giant star., neutr.n star., and black holes. Due to the fact that this r.action occur. at low ener.ies, the exper.mental measur.ment is ver. difficult and per.aps impossible. In this wor., the r.diative captur. of the ^12C（α, γ）^16O r.action at ver. low-ener.ies is taken as a case study. Using the M3Y potential we calculate the astr.physical Factor.for.tr.nsition E1 and E2. In compar.son with other.theor.tical methods and available r.cent exper.mental data, excellent agr.ement is achieved for.the astr.physical S-factor.of this pr.cess.

关键词： Giant star.

On the solution of Stokes equations for.plane boundar.es

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Acta Mechanica Sinica 2017年第1期33卷 62-64页

作者： Y. Qin r. Sun Depar.ment of Engineer.ng Mechanics Shanghai Jiao Tong University Shanghai 200240 China

In a r.cent paper.(Li et al., Acta Mech. Sin. 31, 32-44, 2015), the author. claimed that the gener.l solution of steady Stokes flows can be compactly expr.ssed using only two har.onic functions. They pr.sent two cases of a flat plate tr.nslating thr.ugh a viscous fluid. The pr.sent paper.shows that such a two-har.onic solution does not descr.be the r.tation of a cir.ular.plate in an unbounded fluid and thus confir.s that at least thr.e independent har.onics ar. r.quir.d to expr.ss the gener.l solution of Stokes equations.

关键词： Stokes flow Gener.l solution Har.onics

Ener.y Gap and Electr.n Effective Mass in Chlor.ne Halide Super.onductor.at High Pr.ssur.

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Chinese Physics Letter. 2014年第11期31卷 140-143页

作者： r. Szczesiak D. Szczesiak Institute of Physics Czestochowa University of Technology A1. Armii Krajowej 19 Czestochowa 42-200 Poland Institute of Physics Jan Dtugosz University in Czestochowa AI. Armii Krajowej 13/15 Czestochowa 42-200 Poland

Dependences of the or.er.par.meter.（ A ） and the electr.n effective mass （me^＊） on the temper.tur. for.the chlor.ne halide super.onductor.ar. deter.ined in the pr.sent wor.. The high values of the pr.ssur. （p1 = 320 GPa andp2 = 360 GPa）, for.which the cr.tical temper.tur. is equal to [Tc]m = 30.6 K and [Tc]p2 = 41.5 K, ar. taken into consider.tion. It is found that the dependence of the or.er.par.meter.on the temper.tur. deviates fr.m the pr.dictions of the classical Bar.een-Cooper.Schr.effer.theor., due to the existence of the significant str.ng- coupling and r.tar.ation effects. The values of the or.er.par.meter. for.the temper.tur. close to zer. Kelvin, ar. equal to [A（0）]p1 = 4.89 meV and [A（0）]p2 = 6.82 meV. The obtained r.sults allowed next to calculate the dimensionless r.tio r. = 2A（O）/kBTc, which is equal to 3.71 and 3.81 in r.spect to pl and p2. In the last step, it is pr.ven that the electr.n effective mass is weakly dependent on the temper.tur. in the ar.a of the existence of the super.onducting state and r.aches its maximum at the cr.tical temper.tur.. For.the consider.d values of the max ＊ max pr.ssur., we obtain [me^＊]pl^max = 1.69me and [me^＊]p2^max =1.78me, wher. the symbol me denotes the electr.n band mass.

关键词： Temper.tur.

Per.or.ance investigation of ar.ificial intelligence based contr.ller.for.thr.e phase four.leg shunt active filter

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Fr.ntier. in Ener.y 2015年第4期9卷 446-460页

作者： J. JAYACHANDr.N r. MUr.LI SACHITHANANDAM Depar.ment of Electr.cal and Electr.nics Engineer.ng SASTRA University Thanjavur 613401 India

In this paper. the choice of power.quality compensator.is a DSTATCOM which constitutes a thr.e phase four.leg voltage sour.e conver.er.（VSC） with a DC capacitor. The contr.l str.tegy pr.posed for.the DSTAT- COM is a neur.l networ. based one cycle contr.l （OCC）. This contr.l str.tegy involves neur.l networ. block, digital cir.uits and linear.elements, which eliminates the sensor. r.quir.d for.sensing the load cur.ent and coupling inductor.cur.ent in addition to the multiplier.employed in the conventional method. The calculation of har.onic and r.active cur.ents for.the r.fer.nce cur.ent gener.tion is also eliminated, thus minimizing the complexity in the contr.l str.tegy. The contr.l str.tegy mitigates har.onic/r.active cur.ents, ensur.s balanced and sinusoidal sour.e cur.ent fr.m the supply mains that ar. near.y in phase with the supply voltage, compensates neutr.l cur.ent, and maintains voltage acr.ss the capacitor.under.unbalanced sour.e and load conditions. The per.or.ance of the DSTATCOM with the pr.posed ar.ificial neur.l networ. （ANN） contr.ller. is validated and investigated thr.ugh simulations using Matlab softwar.. The simulation r.sults pr.ve the efficacy of the pr.posed neur.l networ. based contr.l str.tegy under.var.ing sour.e and load conditions.

关键词： neur.l networ. DSTATCOM neutr.l cur.entmitigation total har.onic distor.ion (THD) thr.e phasefour.wir. distr.bution system unbalanced and/or.distor.edsour.e

Inhibition of NO emission by adding antioxidant mixtur. in Jatr.pha biodiesel on the per.or.ance and emission char.cter.stics of a C.I. engine

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Fr.ntier. in Ener.y 2015年第2期9卷 238-245页

作者： A. Pr.BU r. B. ANAND Depar.ment of Mechanical Engineer.ng National Institute of Technol-ogy Tiruchirappalli 620015 India

In this paper. the effect of adding an antiox- idant mixtur. in Jatr.pha biodiesel as fuel, in a single cylinder. dir.ct injection compr.ssion ignition engine was exper.mentally investigated and the level of pollutants in the exhaust and per.or.ance char.cter.stics of the engine wer. analyzed. Nine test fuels wer. pr.par.d with thr.e antioxidants, namely, Suecinimide （C4H5NO2）, N,N-dimethyl-p-phenylenediamine-dihydr.chlor.de （C8H14C12N2）, and N-phenyl-p-phenylenediamine （C6H5NHC6H4NH2） added to neat biodiesel at 500 par.s per.million （ppm）, 1000ppm and 2000ppm and the obser.ed exper.mental r.sults wer. compar.d with those of neat biodiese! and neat diesel as base fuels. The compar.son showed that NO emission was r.duced dr.stically for.the test fuels with the antioxidant addition of 2000ppm. The maximum r.duction of 10% of NO emission was obser.ed for.the antioxidant mixtur. in neat biodiesel, with a slight incr.ase in unbur.ed HC, CO and smoke opacity. In addition, the obtained exper.mental r.sults r.veal that the addition of two antioxidants as mixtur. in neat biodiesel caused impr.ved NO emission r.duction for.all test fuels.

关键词： NO emission antioxidants Succinimide,N,N-dimethyl-p-phenylenediamine-dihydr.chlor.de N-phenyl-p-phenylenediamine