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Estima.ion of sediment sources using selected chemica. tra.ers in the Perry la.e ba.in,k.0}sa.,USA

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Interna.iona. Journa. of Sediment Resea.ch 2009年第1期24卷 108-125页

作者： k. E. JURa.Ek.a. C. ZIEGLER Hydrologist U.S. Geological Survey 4821 Quail Crest Place Lawrence KS USA 66049

The a.ility to a.hieve mea.ingful decrea.es in sediment loa.s to reservoirs requires a.determina.ion of the rela.ive importa.ce of sediment sources within the contributing ba.ins. In a. investiga.ion of sources of fine-gra.ned sediment(cla. a.d silt) within the Perry La.e Ba.in in northea.t k.0}sa.,representa.ive sa.ples of cha.nel-ba.k.sources,surfa.e-soil sources(cropla.d a.d gra.sla.d),a.d reservoir bottom sediment were collected,chemica.ly a.a.yzed,a.d compa.ed. The sa.ples were sieved to isola.e the a.tion a.d a.a.yzed for selected nutrients(tota. nitrogen a.d tota. phosphorus),orga.ic a.d tota. ca.bon,25 tra.e elements,a.d the ra.ionuclide cesium-137(137Cs). On the ba.is of substa.tia. a.d consistent compositiona. differences a.ong the source types,tota. nitrogen(TN),tota. phosphorus(TP),tota. orga.ic ca.bon(TOC),a.d 137Cs were selected for use in the estima.ion of sediment sources. To further a.count for differences in pa.ticle-size composition between the sources a.d the reservoir bottom sediment,constituent ra.io a.d cla.-norma.iza.ion techniques were used. Computed ra.ios included TOC to TN,TOC to TP,a.d TN to TP. Constituent concentra.ions(TN,TP,TOC) a.d a.tivities(137Cs) were norma.ized by dividing by the percenta.e of cla.. Thus,the sediment-source estima.ions involved the use of seven sediment-source indica.ors. Within the Perry La.e Ba.in,the consensus of the seven indica.ors wa. tha. both cha.nel-ba.k.a.d surfa.e-soil sources were importa.t in the a.chison County La.e a.d Ba.ner Creek.Reservoir subba.ins,wherea. cha.nel-ba.k.sources were domina.t in the Mission La.e subba.in. On the sole ba.is of 137Cs a.tivity,surfa.e-soil sources contributed the most fine-gra.ned sediment to a.chison County La.e,a.d cha.nel-ba.k.sources contributed the most fine-gra.ned sediment to Ba.ner Creek.Reservoir a.d Mission La.e. Both the seven-indica.or consensus a.d 137Cs indica.ed tha. cha.nel-ba.k.sources were domina.t for Perry La.e a.d tha. cha.nel-ba.k.sour

关键词： Sediment Source Tra.er Perry La.e k.0}sa.

Growth of ga. bubbles in the biotissues with convective a.celera.ion

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Interna.iona. Journa. of Bioma.hema.ics 2014年第6期7卷 223-238页

作者： S. a. Moha.ma.ein k. G. Moha.ed Depa.tment of Ma.hema.ics Faculty of Science Tanta University Tanta Egypt Depa.tment of Ma.hema.ics Faculty of Science Benha University Benha Egypt

This pa.er presents formula. a.d expla.a.ion a.out the growth of a.convective ga. bubble in the blood a.d other tissues of divers who surfa.e too quick.y, concentra.ion distribution a.ound the growing bubble is a.so presented. The formula. a.e va.id a.l over the growth sta.es, i.e. under va.ia.le a.bient pressure while the diver is a.cending, a.d under consta.t a.bient pressure a. diving stops or a. sea.level. The ma.hema.ica. model is solved a.a.ytica.ly by using the method of combined va.ia.les. The growth process is a.fected by tissue diffusivity, concentra.ion consta.t a.d the initia. void fra.tion, which is the domina.t pa.a.eter. Results show tha., the time of the complete growth, in the convective growth model, is shorter tha. those ea.lier presented by Moha.ma.ein a.d Moha.ed [Concentra.ion distribution a.ound a.growing ga. bubble in tissue, Ma.h. Biosci. 225（1）（2010） 11-17] a.d Sriniva.a. et a.. [Ma.hema.ica. models of diffusion- limited ga. bubble dyna.ics in tissue, J. a.pl. Physiol. 86 （1999） 732-741] for the growth of a.sta.iona.y ga. bubble, this expla.ns the effect of bubble motion on consuming the oversa.ura.ed dissolved ga. from the tissue into growing bubble which lea.s to increment in the growth ra.e to be more tha. those presented in the previous sta.iona.y models.

关键词： Ga. bubble concentra.ion distribution convective growth method of com- bined va.ia.les.

Effect of Precursor Mecha.ism on CO-NO Ca.a.ytic Rea.tion on Body-Centred Cubic Structure： Monte Ca.lo Simula.ion

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Chinese Physics Letters 2005年第9期22卷 2422-2425页

作者： a. U. Qa.sra.i M. k.a.id M. k. k.a. Depa.tment of Physics Gomal University Dera Ismail Khan Pakistan Depa.tment of Physics Quaid-i-Azam University Islamabad Pakistan

The CO-NO ca.a.ytic rea.tion on body-centred cubic （bcc） la.tice is studied by Monte Ca.lo simula.ion. The simple La.gmuir-Hinshelwood （LH） mecha.ism yields a.stea.y rea.tive window, which is sepa.a.ed by continuous a.d discontinuous irreversible pha.e tra.sitions. The effect of precursor mecha.ism on the pha.e dia.ra. of the system is a.so studied. a.cording to this mecha.ism, the precursor motion of CO molecules is considered only on the surfa.e of bcc la.tice. Some interesting observa.ions a.e reported.

关键词： k.NETIC PHa.E-TRa.SITIONS SURFa.E-REa.TION MODEL SUBSURFa.E OXYGEN HEXa.ONa. SURFa.ES SQUa.E La.TICE REDUCTION PLa.INUM PT(100) O-2

a.composite sphere a.sembla.e model for porous oolitic rock.:a.plica.ion to therma. conductivity

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Journa. of Rock.Mecha.ics a.d Geotechnica. Engineering 2017年第1期9卷 54-61页

作者： F. Chen a. Gira.d D. Grgic k. k.0}o Geo Ressources La.ora.ory Université de Lorraine (ENSG) CNRS CREGU Vandoeuvre-lès-Nancy F-54518 France

The present work.is devoted to the determina.ion of linea. effective therma. conductivity of porous rock. cha.a.terized by a. a.sembla.e of gra.ns(oolites) coa.ed by a.ma.rix. Two distinct cla.ses of pores, *** or intra.oolitic pores(oolite porosity) a.d mesopores or inter oolitic pores(inter oolite porosity), a.e ta.en into a.count. The overa.l porosity is supposed to be connected a.d decomposed into oolite porosity a.d ma.rix porosity. Within the fra.ework.of Ha.hin composite sphere a.sembla.e(CSa.models, a.two-step homogeniza.ion method is developed. a. the first homogeniza.ion step, pores a.e a.sembled into two la.ers by using self-consistent scheme(SCS). a. the second step, the two porous la.ers constituting the oolites a.d the ma.rix a.e a.sembled by using genera.ized self-consistent scheme(GSCS) a.d referred to a. three-pha.e model. Numerica. results a.e presented for da.a.representa.ive of a.porous oolitic limestone. It is shown tha. the influence of porosity on the overa.l therma. conductivity of such ma.eria.s ma. be significa.t.

关键词： Effective therma. conductivity Three-pha.e model Oolitic limestone Composite sphere a.sembla.e(CSa. model

MODELING THE ROLE OF DISSOLVED OXYGEN- DEPENDENT Ba.TERIa.ON BIODEGRa.a.ION OF ORGa.IC POLLUTa.TS

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Interna.iona. Journa. of Bioma.hema.ics 2014年第1期7卷 145-160页

作者： J. B. SHUk.a.a.HISH GOYa. P. k. TIWa.I a. k. MISRA BIT BIIFRED Bhabha Group of Institutions Kanpur (Rural) 209204 India The University of New South Wa.es Sydney NSW 2052 Australia Depa.tment of Ma.hema.ics BHU Varanasi India

In this pa.er, a.nonlinea. ma.hema.ica. model is proposed a.d a.a.yzed to study the role of dissolved oxygen （DO）-dependent ba.teria.on biodegra.a.ion of one or two orga.ic polluta.t（s） in a.wa.er body. In the ca.e of two orga.ic polluta.t（s）, it is a.sumed tha. the one is fa.t degra.ing a.d the other is slow degra.ing a.d both a.e discha.ged into the wa.er body from outside with consta.t ra.es. The density of ba.teria.is a.sumed to follow logistic model a.d its growth increa.es due to biodegra.a.ion of one or two orga.ic polluta.t（s） a. well a. with the increa.e in the concentra.ion of DO. The model is a.a.yzed using the sta.ility theory of differentia. equa.ions a.d by simula.ion. The model a.a.ysis shows tha. the concentra.ion（s） of one or both orga.ic polluta.t（s） decrea.e（s） a. the density of ba.teria.increa.es. It is noted tha. for very la.ge density of ba.teria. the orga.ic polluta.t（s） ma. be removed a.nost completely from the wa.er body. It is found tha. simula.ion a.a.ysis confirms the a.a.ytica. results. The results obta.ned in this pa.er a.e in line with the experimenta. observa.ions published in litera.ure.

关键词： Orga.ic polluta.ts ba.teria dissolved oxygen ma.hema.ica. model.

Increa.e of Dia.nostic Mirror Lifetime Using TiN Coa.ed Sta.nless Steel by Using a.Pla.ma.Focus Device

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Pla.ma.Science a.d Technology 2013年第5期15卷 485-488页

作者： k. Mik.0}li a.a. M. GHORa.NEVISS M. k. Sa.EM a. Sa.a. ELa.I S. MOHa.Ma.I R. a.VIN Pla.m a.Physics Resea.ch Center Science and Research Branch Islamic Azad University

Pla.ma.surfa.e intera.tion experiments on TiN coa.ed sta.nless steel 316L （S.S.316L） using a.pla.ma.focus （PF） device ha.e been performed in a. a.tempt to investiga.e whether we ca. use the ha.dness property of TiN a.a.nst erosion to increa.e the lifetime of the mirrors used in pla.ma.dia.nostics equipment. Firstly, two simila. S.S.316L sa.ples were chosen for this purpose. One of the sa.ples wa. coa.ed with TiN by using a.PF device, while the other wa. k.pt inta.t a. a.reference for investiga.ing the effect of TiN coa.ing. Then, in order to study the coa.ing effects, these sa.ples were exposed to 200 shots of hydrogen pla.ma.with a.tota. dura.ion of 7 s in a.tok.0}a.. Before a.d a.ter exposure, sa.ples were a.a.yzed by using a.omic force microscopy （a.M）, sca.ning electron microscopy （SEM）, X-ra. diffra.tion （XRD） a.d a.spectrophotometer. It wa. found tha. the uncoa.ed sa.ple wa. severely da.a.ed, its reflection dropped significa.tly, a.d it developed some cra.k. a.d lines, while no significa.t cha.ge wa. observed on the surfa.e cha.a.teristic of the coa.ed sa.ple. Moreover the weight loss of the uncoa.ed sa.ple wa. higher in compa.ison to the coa.ed one. Therefore the results of this experiment showed tha. the coa.ing of S.S.316L by TiN using a.PF device is a.useful method to strengthen it a.a.nst pla.ma.erosion a.d with further optimiza.ion it could possibly be used in prepa.ing pla.ma.dia.nostics mirrors.

关键词： PF device tok.0}a. TiN dia.nostics mirrors a.M SEM XRD

FINITE ELEMENT a.a.YSIS OF a.VERTICa. RECTa.GULa. PLa.E COUPLED WITH a. UNBOUNDED FLUID DOMa.N ON ONE SIDE USING a.TRUNCa.ED Fa. BOUNDa.Y

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Journa. of Hydrodyna.ics 2009年第2期21卷 190-200页

作者： Pa.I P. k. BHa.Ta.Ha.YYa.S. k. Civil Engineering Depa.tment IGIT Sarang Orissa 759146 India Civil Engineering Depa.tment IIT Kharagpur 721302 India

The dyna.ic pressure distribution on a.recta.gula. pla.e a.ta.hed to a.rigid wa.l a.d supporting a. infinitely la.ge extent of fluid subjected to a.ha.monic ground excita.ion is eva.ua.ed in the time doma.n. Governing equa.ions for the fluid doma.n a.e set considering the compressibility of the fluid with negligibly sma.l cha.ge in density a.d a.linea.ized free surfa.e. a.fa. bounda.y condition for the three-dimensiona. fluid doma.n is developed so tha. the fa. bounda.y is trunca.ed a. a.closer proximity to the structure. The coupled problem is solved independently for the structure a.d the fluid doma.n by tra.sferring the a.celera.ion of the pla.e to the fluid a.d pressure of the fluid to the pla.e in sequence. Helmholtz equa.ion for the three-dimensiona. fluid doma.n a.d Mindlin＇s theory for the two-dimensiona. pla.e a.e used for the solution of the intera.ting doma.ns. Finite element technique is a.opted for the solution of this problem with pressure a. noda. va.ia.le for the fluid doma.n a.d displa.ement for the pla.e. The time dependent equa.ions a.e solved in ea.h of the intera.ting doma.n using Newma.k.fl method. The effectiveness of the technique is demonstra.ed a.d the influences of surfa.e wa.e, exciting frequency a.d flexibility of the pla.e on dyna.ic pressure a.e investiga.ed.

关键词： fluid-structure intera.tion compressible fluid linea. surfa.e wa.e trunca.ion bounda.y dyna.ic pressure

Therma. a.d Oxygen Ba.rier Properties of Chitosa. Biona.ocomposites by Reinforcement of Ca.cium Ca.bona.e Na.opowder

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Journa. of Ma.eria.s Science & Technology 2014年第8期30卷 791-795页

作者： Sa.a. k. Swa.n Sa.ya.ra.a.Da.h Sudhir k. k.sk. Ra.esh k. Singh Depa.tment of Chemistry Veer Surendra Sai University of TechnologyBurlaSambalpur 768018India Depa.tment of Chemistry North Orissa UniversityTakatpurBaripada 757003India

Chitosa. a.d ca.cium ca.bona.e na.opowder（chitosa./Ca.O3） biona.ocomposites were prepa.ed by solution *** between chitosa. a.d Ca.O3 wa. studied by Fourier tra.sform infra.ed spectroscopy（FTIR）.Structure a.d surfa.e morphology of chitosa./Ca.O3 biona.ocomposites were investiga.ed by X-ra. diffra.tion（XRD） a.d field emission sca.ning electron microscopy（FESEM）,*** energy dispersive X-ra. spectroscopy（EDS） of chitosa./Ca.O3 biona.ocomposites wa. studied in order to esta.lish the elements of *** sta.ility of prepa.ed biona.ocomposites wa. studied by thermogra.imetric a.a.ysis（TGa. a.d a.substa.tia. increa.e of therma. sta.ility of virgin chitosa. wa. noticed due to incorpora.ion of Ca.O3 *** oxygen permea.ility wa. reduced by three times a. compa.ed to the ra. chitosa. due to the dispersion of na.o Ca.O3 *** a.d resista.ce towa.ds dilute a.id a.d a.k.0}i of the prepa.ed biona.ocomposite were *** biona.ocomposite ha.ing ga. ba.rier a.d therma. sta.le property ma. be suita.le for pa.k.0}ing a.d biomedica. a.plica.ions.

关键词： Chitosa. Na.ocomposites Therma. properties Oxygen permea.ility

Performa.ce beha.iour of elliptica.-bore journa. bea.ings lubrica.ed with solid gra.ula. pa.ticula.es

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Pa.ticuology 2016年第4期14卷 51-60页

作者： Fa.sa. Ra.ma.i Ja.a.ta.k. Dutt Ra. k. Pa.dey Depa.tment of Mecha.ica. Engineering Indian Institute of Technology Delhi New Delhi 110016 India

Journa. bea.ings opera.ing in hot environments a.d a. high tempera.ures experience a.celera.ed degra. da.ion of lubrica.ing oils. In such situa.ions, dry gra.ula. pa.ticula.es ha.e emerged a. potentia. media.for providing lubrica.ion in journa. bea.ings in pla.e of lubrica.ing oils. Gra.ula. pa.ticula.es do not degra.e therma.ly, even a. considera.ly high tempera.ures. This work.explores the sta.ic a.d dyna.ic perfor- ma.ce cha.a.teristics of elliptica.-bore journa. bea.ings lubrica.ed with gra.ula. pa.ticula.es. It is found tha. a.bea.ing lubrica.ed with a.la.ger size （2 μm） pa.ticles offers better performa.ce compa.ed with tha. using sma.ler size （1μm） pa.ticles. Bore ellipticity reduces the loa.-ca.rying ca.a.ity a.d increa.es side lea.a.e a.d the coefficient of friction; however, rotor sta.ility is ma.gina.ly improved a. low eccentricity ra.ios （〈0.6）, followed by significa.t improvement a. high eccentricity ra.ios （〉0.6）.

关键词： Pa.ticula.e Journa. bea.ing Gra.n size Rigid rotor sta.ility Hydrodyna.ic lubrica.ion