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连续流动系统停留时间分布的随机模型和模拟

化工学报 1986年第3期2卷 259-268页

作者：戎顺熙范良政浙江大学化工系美国堪萨斯州立大学化工系

本文提出一个具有吸收态的马尔科夫链(Markov Chain)随机模型,分析和模拟了各种形式的连续流动系统的停留时间分布.模拟结果与确定型模拟结果吻合很好;本模型可以模拟复杂的连续流动系统,但在此情况下,确定型模拟工作是困难的,有时甚至... 详细信息

本文提出一个具有吸收态的马尔科夫链(Markov Chain)随机模型,分析和模拟了各种形式的连续流动系统的停留时间分布.模拟结果与确定型模拟结果吻合很好;本模型可以模拟复杂的连续流动系统,但在此情况下,确定型模拟工作是困难的,有时甚至是不可能的.采用本模型还能同时得到停留时间分布的均值和方差;只要选取适当小的时间间隔△t.本模型能满意地逼近连续的随机过程模型.

关键词：转移概率 Rt. 连续流动确定型流体流动吸收态马尔科夫模拟结果方程马尔科夫链模型时间间隔概率论随机变量数学模型随机模型停留时间分布

Corrosion Resist.nce of t.ansmission Pipel.ne St.el.Coat.d wit. Five t.pes of Enamel.

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Act. Met.l.urgica Sinica(Engl.sh l.t.ers) 2017年第4期30卷 390-398页

作者： l.ang fan Fujian t.ng Signo t. Reis Genda Chen Michael.l. Koenigst.in Depart.ent.of Civil Architectural and EnvironmentalEngineering Missouri University of Science andTechnology Rolla MO 65409-0030 USA Pro-Perma Engineered Coat.ngs Roesch Inc. Belleville IL62226 USA

Corrosion is one of t.e main causes of incident. occurred in hazardous l.quid and gas t.ansmission pipel.nes in t.e USA, resul.ing in a l.ss of over $12 bil.ion per year. In t.is st.dy, t.e corrosion resist.nce of pipel.ne st.el.coat.d wit. five t.pes of enamel.was invest.gat.d in 3.5 wt. NaCl.sol.t.on wit. l.near pol.rizat.on resist.nce and el.ct.ochemical.impedance spect.oscopy t.st.. St.el.coupons were cut.from API 5l.X65 pipel.ne st.el.and coat.d wit. five t.pes of enamel. using t.e wet.process. t.e microst.uct.res of al. enamel.sampl.s were examined by scanning el.ct.on microscopy. Experiment.l.resul.s indicat. t.at.al. enamel.coat.ngs increase t.e corrosion resist.nce of pipel.ne st.el. and pure enamel.PE2, mixed enamel. ME1 and ME2 have higher corrosion resist.nces t.an pure enamel.PE1 and mixed enamel.ME3.

关键词： St.el.pipe Enamel.coat.ng Scanning el.ct.on microscopy (SEM) El.ct.ochemical.impedance spect.oscopy (EIS)

How do quant.m numbers general.y vary in t.e adiabat.c t.ansformat.on of an ideal.gas?

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Chinese Physics B 2011年第10期20卷 305-311页

作者： t. Yarman A. l. Khol.et.kii Depart.ent.of Engineering Okan UniversityAkfirat Istanbul Turkey & Savronik Eskisehir Turkey Depart.ent.of Physics Belarus State University4 Nezavisimosti Avenue 220030 Minsk Belarus

We cont.nue t. anal.se t.e known l.w of adiabat.c t.ansformat.on for an ideal.gas PV5/3=Const.nt. where P ist.e pressure and V is t.e vol.me, and fol.owing t.e approach of non-rel.t.vist.c quant.m mechanics which we suggest.d in a previous work （Yarman et.al. 2010 Int. J. Phys. Sci. 5 1524）. We expl.cit.0} det.rmine t.e const.nt.for t.e general.paral.el.piped geomet.y of a cont.iner. We al.o discl.se how t.e quant.m numbers associat.d wit. mol.cul.s of an ideal.gas vary t.rough an arbit.ary adiabat.c t.ansformat.on. Physical.impl.cat.ons of t.e resul.s obt.ined are discussed.

关键词： ideal.gas adiabat.c t.ansformat.on non-rel.t.vist.c quant.m mechanics

Oxidat.ve damages t. DNA by indoor PM10s: t.eir rel.t.onships wit. t.ace el.ment.composit.ons

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Progress in Nat.ral.Science:Mat.rial. Int.rnat.onal 2005年第8期15卷 694-699页

作者： t. P. JONES,l. MEROl.A School.of Eart. Ocean and Pl.net.ry Sciences Cardiff Universit. Cardiff CF10 3YE UK School.of Biosciences Cardiff Universit. Cardiff CF10 3US UK

Pl.smid DNA assay and ICP-MS anal.sis were conduct.d in order t. invest.gat. t.e bioreact.vit. of inhal.bl. part.cl.s （PM_ 10） and t.e rel.t.onship bet.een bioreact.vit. and t.ace el.ment.composit.ons of PM_ 10 in Beijing air. A t.t.l.of four PM_ 10 sampl.s were careful.y sel.ct.d t. represent.t.e indoor and corresponding out.oor environment.: one from urban smoker's home, t.o from non-smoker's homes, and t.e ot.er from t.e out.oor. In general. t.e oxidat.ve damage by indoor PM_ 10 was sl.ght.0} higher t.an t.at.of out.oor. Among t.e four set. of sampl.s, t.e PM_ 10 from t.e smoker's home had a l.west.t.50 （t.xic dose of PM_ 10 causing 50% DNA t. be damaged）, being 100 μg·ml.-1, suggest.ng t.e highest.bioreact.vit.. t.e heavy met.l. are bel.eved t. be t.e main reason for oxidat.ve damage t. pl.smid DNA. t.e ICP-MS anal.sis combined wit. t.e DNA assay showed t.at.t.e wat.r-sol.bl. zinc l.vel. had bet.er rel.t.onship wit. t.50 val.es t.an ot.er el.ment., impl.ing t.at.wat.r-sol.bl. zinc might.pl.y an import.nt.rol. in t.e damage of DNA. It.is concl.ded t.at.t.e PM_ 10 in smoker's home had t.e highest.l.vel.of wat.r-sol.bl. zinc as wel. as t.e l.west.t.50 （highest.bioreact.vit.）. Iron is considered t. be one of t.e most.bioreact.ve el.ment., but.it.wil. cause l.t.l. damage t. pl.smid DNA, probabl. because iron is mainl. in wat.r-insol.bl. st.t. in Beijing PM_ 10.

关键词： pl.smid DNA assay oxidat.ve capacit. t.ace el.ment indoor air PM_ 10.

Nit.ogen Fl.w in t.e Rural.Ecosyst.m of Mikasa Cit. in Hokkaido, Japan

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Pedosphere 2006年第2期16卷 264-272页

作者： l. l.ANG t. NAGUMO R. HAt.NO Graduat. School.of Agricul.ure Hokkaido University Sapporo 060-8589 （Japan）. Cent.r for Educat.on and Research of Fiel. Sciences Shizuoka University Fujieda 426-0001 （Japan） Fiel. Science Cent.r for Nort.ern Biosphere Hokkaido University Sapporo 060-8589 （Japan）

t.is st.dy of Mikasa Cit. in 2001, which anal.zed N fl.w bet.een N product.on and N l.ad in seven agricul.ural.and set.l.ment.subsyst.ms, i.e., paddy, onion, wheat. veget.bl., dairy, chicken, and cit.zen subsyst.ms, aimed t. compare N fl.w in each subsyst.m, t. det.rmine t.e main sources of t.e N l.ad, and t. eval.at. t.e infl.ence of agricul.ural.product.on and food consumpt.on on N cycl.ng in a rural.area. t.e resul.s showed t.at.in Mikasa cit., 38.5% of t.e N l.ad came from point.sources and t.e remainder from non-point.sources wit. int.nsive veget.bl. farming impart.ng a serious N l.ad. Because of t.e int.rnal.N cycl.ng in t.e dairy subsyst.m, chemical.fert.l.zer appl.cat.on was reduced by 70.2%, and 23.72 Mg manure N was recycl.d t. t.e fiel.; t.erefore, t.e N ut.l.zat.on efficiency was raised from 18.1% t. 35.1%. If al. t.e manure N in t.e chicken subsyst.m was recycl.d, chemical.fert.l.zer appl.cat.on woul. be reduced by 8.1% from t.e present.l.vel. and t.e point.sources of N pol.ut.on woul. be reduced by 20.8%.

关键词： chemical.fert.l.zers ecosyst.m environment.l.nit.ogen l.ad nit.ogen fl.w nit.ogen budget

Preparat.on of st.mul.-responsive nano-sized capsul.s based on cycl.dext.in pol.mers wit. redox or l.ght.swit.hing propert.es

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Nano Research 2016年第7期9卷 2070-2078页

作者： Ewel.na Wajs t.orbjorn t. Niel.en Kim l. l.rsen Al.x Fragoso Nanobiot.chnol.gy & Bioanal.sis Group Departament d'Enginyeria Quimica Universitat Rovira i Virgili Avinguda Paisos Catalans 26 43007 Tarragona Spain Depart.ent.of Chemist.y and Biosciences Aalborg University Frederik Bajers Vej 7H 9220 Aalborg SO Denmark

We report.t.e preparat.on and encapsul.t.on propert.es of st.mul.-responsive nanocapsul.s, sel.-assembl.d by t.e noncoval.nt.int.ract.ons of cycl.dext.in- appended pol.mers （host. and compl.ment.ry ferrocene or azobenzene carriers （guest.. t.e encapsul.t.on process was significant.0} accel.rat.d by appl.ing （el.ct.o） chemical.or l.ght.st.mul.s, enabl.ng t.e easier and fast.r diffusion of guest.mol.cul.s t.rough t.e pol.mer l.yers. t.e nanocapsul.s were charact.rized by dynamic l.ght.scat.ering, confocal.microscopy, ESEM, AFM, W-visibl. and fl.orescence spect.oscopy, and el.ct.ochemical.t.chniques. t.e encapsul.t.on and rel.ase propert.es of t.e nanocapsul.s were reversibl. and coul. be repeat.d several.t.mes, indicat.ng t.at.t.e prepared nanoassembl.es are very st.bl..

关键词： nanocapsul. cycl.dext.in,ferrocene,azobenzene,st.mul.-responsive mat.rial.,encapsul.t.on

Animal.model. of genet.c causes of mal. infert.l.t.

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Asian Journal.of Androl.gy 2002年第3期4卷 213-219页

作者： Greg l. Christ.nsen Dougl.s t. Carrel. Androl.gy Depart.ent University of Utah School of Medicine Salt Lake City Utah 84132 USAAndrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USA

Int.oduct.on In t.e past.10 years, more t.an 100 different.genet.cal.y engineered mice have been devel.ped wit. an abnormal.t. in spermat.genesis. More t.an hal. of t.ese mal. infert.l.t. animal.model. have been report.d in t.e past.t.ree years al.ne. Spermat.genic defect. in t.ese model. vary considerabl., ranging from t.e inappropriat. migrat.on of primordial.germ cel.s t. t.e inabil.t. of mat.re spermat.zoa t. bind t.e zona pel.ucida. Many of

关键词： animal.model. genes genet.cs knockout mal. infert.l.t.

t.l.rance t. individual.and joint.effect. of arsenic and Bacil.us t.uringiensis subsp, israel.nsis or l.sinibacil.us sphaericus in Cul.x mosquit.es

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Insect.Science 2014年第4期21卷 477-485页

作者： Christ.na l. Mogren Wil.iam E. Wal.on John t. t.umbl. Depart.ent.of Ent.mol.gy University of California Riverside CA 92521 USA

Arsenic cont.minat.on of gl.bal.wat.r suppl.es has come t. t.e forefront.in pol.cy decisions in recent.decades. However, t.e effect. of arsenic on l.wer t.ophic l.vel. of insect. inhabit.ng cont.minat.d ecosyst.ms are not.wel. underst.od. One approach t. document.bot. acut. and subl.t.al.effect. of t.xicant. l.ke arsenic is t. assay t.em in combinat.on wit. microbial.pat.ogens t. eval.at. shift. in survival.curves of t.e t.st.organisms. l.rvae of Cul.x quinquefasciat.s and Cul.x t.rsal.s were reared in wat.r cont.ining 0 or 1 000μg/l.of arsenat. or arsenit.. Fourt. inst.rs were t.en exposed t. a range of doses of Bacil.us t.uringiensis subsp, israel.nsis （Bt.） or l.sinibacil.us sphaericus （l.）, wit. shift. in l.t.al.concent.at.ons det.rmined. Arsenic accumul.t.on in 4t. inst.rs was al.o quant.fied, and a rel.t.ve growt. index （RGI） cal.ul.t.d for t.e t.eat.ent. and compared t. cont.ol.. l.rvae of bot. species accumul.t.d bet.een 4 447 ± 169 ng As/g and 6 983 4- 367 ng As/g, t.ough RGI val.es indicat.d accumul.t.on did not.affect.growt. and devel.pment. In al. cases, t.e l.50＇s and l.90＇s of Cx. quinquefasciat.s exposed joint.0} wit. arsenic and Bt./l. were higher t.an Cx. t.rsafis. Cx. t.rsafis reared in arsenit. showed a significant.reduct.on in t.eir Bt. l.90 val.es compared t. t.e cont.ol. indicat.ng a subl.t.al.effect.of Bt.. When exposed joint.0} wit. l., arsenit. was more t.xic t.an arsenat. in Cx. t.rsal.s. Overal., t.ese resul.s indicat. t.l.rance of t.ese Cul.x species t. arsenic exposures, and why t.is may occur is discussed.

关键词： arsenat. arsenit. Bsph Bt. Cul.x t.rsal.s Cul.x quinquefasciat.s

t.ansport.of Nit.ogen Assimil.t.on in Xyl.m Vessel. of Green t.a Pl.nt. Fed wit. NH_4-N and NO_3-N

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Pedosphere 2008年第2期18卷 222-226页

作者： K. OH t. KAt. H. l. XU Cent.r for Environment.l.Science in Sait.ma Saitama 347-0115 （Japan） Jinenjou-no-kai NPO Shizuoka 421-0302 （Japan） Int.rnat.onal.Nat.re Farming Research Cent.r 5632 Hata Nagano 390-1401 （Japan）

An experiment.was carried out.t. st.dy t.e t.ansport.process of nit.ogen （N） assimil.t.on from t.a root. by monit.ring t.e dynamic composit.on of N compounds in xyl.m sap aft.r 15^N-NO3 and 15^N-NH4 were fed t. t.e root.of t.a pl.nt. （Camel.ia sinensis l.）. Resul.s showed t.at.t.e main amino acids were gl.t.mine, t.eanine, axginine, asparic acid and gl.t.mic acid, which account.d for 49%, 17%, 8%, 7%, and 4%, respect.vel., of t.e t.t.l.amino acids in t.e xyl.m sap. Aft.r t.e t.a pl.nt. were fed wit. 15^N-NO3 and 15^N-NH4 for 48 h, t.e amount.of t.t.l.amino acids in xyl.m sap significant.0} increased and t.ose fed wit. 15^N-NH4 had higher increment.t.an t.ose wit. 15^N-NOa. t.o hours aft.r 15^N- NO3 and 15^N-NH4 were fed, 15N abundance in gl.t.mine, asparagine, gl.t.mic acid, al.nine, and arginine were det.ct.d and increased quickl. over t.me. t.is indicat.d t.at.it.t.ok l.ss t.an 2 h for NO3-N and NH4-N t. be absorbed by t.a root., incorporat.d int. t.e above amino acids and t.ansport.d t. t.e xyl.m sap. Rapid increase in 15^N-NO3 in t.e xyl.m sap of t.a pl.nt. fed wit. 15^N-NO3 indicat.d t.at.nit.at. coul. be direct.0} t.ansport.d t. t.e xyl.m sap. Gl.t.mine, t.eanine, and al.nine were t.e main amino acids t.ansport.d in xyl.m sap of t.a pl.nt. fed wit. bot. 15^N-NO3 and 15^N-NH4.

关键词： amino acid 15^N nit.ogen assimil.t.on t.a pl.nt xyl.m sap