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Jour.al of Envir.nmental Sciences 2013年第7期25卷 1431-1440页

作者： Ivanec-Gor.nina r.ta Kulys Juozas Depar.ment of Chemistr. and Bioengineer.ng Faculty of Fundamental Sciences Vilnius Gediminas Technical University Institute of Biochemistr. Vilnius University

The kinetics of the r.combinant Copr.nus ciner.us per.xidase-catalyzed2-naphthol oxidationwas investigated in the pr.sence of r.amnolipid biosur.actant JBr.25 and synthetic sur.actant Sur.ynol465 at pH 5.5 and25°C,with concentr.tions of （bio）sur.actants both less than cr.tical micelle concentr.tions （CMC） and lar.er.than CMC. Itwas shown that monomer. of JBr.25 aswell as monomer. of Sur.ynol465 had an enhancing effect on the conver.ion of2-naphthol indose r.sponse manner.anddid not influence the initial r.te of 2-naphthol oxidation. The r.sultswer. accounted by a scheme,which contains a stadium of enzyme inhibition by oligomer.c2- naphthol oxidation pr.ducts. The action of the biosur.actant＇s （or.synthetic sur.actant＇s） monomer.was explained by avoidance of the enzyme active center.clothingwith oligomer.. Similar.r.sults havedemonstr.ted the potential of r.amnolipid biosur.actant JBr.25due to its biodegr.dability. When biosur.actants＇ concentr.tions ar. lar.er.than CMC, （bio）sur.actants have an opposite effect on the oxidation of2-naphthol by per.xidase.

关键词： oxidation per.xidase biosur.actant cr.tical micelle concentr.tion

Ear.y Holocene climate signals fr.m stable isotope composition of ice wedges in the Char. Basin,nor.her. Tr.nsbaikalia,r.ssia

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Geoscience Fr.ntier. 2018年第2期9卷 471-483页

作者： Yur.j K.Vasil’chuk Alla C.Vasil’chuk Julia V.Stanilovskaya Geogr.phy and Geology Depar.ments Lomonosov Moscow State UniversityMoscowRussia Ser.eev Envir.nmental Geoscience Institute of the r.ssian Academy of Sciences Russia

Stable isotope composition of syngenetic and epigenetic ice wedges, r.diocar.on age, and pollen spectr. of the sur.ounding deposits wer. studied dur.ng long ter. investigations at the "Belyi Klyuch" site on the fir.t(6-8 m height) ter.ace of the Char. r.ver.720 m.a.s.l.) in nor.her. Tr.nsbaikalia to assess climatic conditions dur.ng ice-wedge for.ation. It was r.vealed that Holocene ice wedges had been for.ed fr.m 10 to 7.5 ka 14 C BP. The isotope composition(δ^(18)O, δ~2 H) of r.lict ice wedges is the lightest and amounts-23‰ and-185‰, cor.espondingly. The isotopic compositions of ice lenses fr.m sandy loam above ice wedges ar.-15.7‰, and-133‰; of small ice wedge in peat and sand ar.-15.3‰ and-117.9‰, *** of the ice wedge isotope composition has yielded that mean winter.temper.tur.s dur.ng cold stages of Holocene optimum wer. lower.than today, dur.ng war. stages they wer. close to moder. ones. Dur.ng the coldest stages of Holocene optimum the total annual fr.ezing index var.ed fr.m-5100 to-5700 ℃ degr.e days, i.e. 300-600 ℃ degr.e days colder.than dur.ng extr.mely sever. moder. winter.. The total annual thawing index var.ed fr.m 1300 to 1800 ℃ degr.e days, which was slightly higher.than moder. ones.

关键词： Holocene Ice wedge Stable isotopes Souther. per.afr.st ar.as Nor.her. Tr.nsbaikalia

Singlet Oxygen Gener.tion and Photoinduced Char.e Separ.tion of Tetr. Polyethyleneglycol Functionalized Zinc Phthalocyanine-Fuller.ne Dyad

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Chinese Jour.al of Chemistr. 2016年第10期34卷 969-974页

作者： Habtom B. Gobeze ta Tr.m Chandr. B. KC r.ber. r. Cantu Paul A. Kar. Fr.ncis D'Souza Depar.ment of Chemistr. University of North Texas 1155 Union Circle #305070 Denton TX 76203-5017 USA Depar.ment of Physical Sciences and Mathematics Wayne State College 111 Main Street Wayne Nebraska 68787 USA Advanced Mater.als and Manufactur.ng Pr.cesses Institute (A MMPI) UNT-Discovery Park 3940 N. Elm St. #E132 Denton TX 76207-7102 USA

Utilization of polyethyleneglycol （PEG） functionalized zinc phthalocyanine, （PEG）4ZnPc in （i） singlet oxygen gener.tion, and （ii） in building ener.y har.esting donor.acceptor.systems using fuller.ne, C60 as an acceptor.via the well-known metal-ligand axial coor.ination appr.ach is r.por.ed. The （PEG）4ZnPe was found to be capable of pr.ducing singlet oxygen with a quantum yield, ooa of 0.77 in toluene, a value higher.than that obtained for.pr.stine （t-bu）4ZnPc （φ△=0.54） car.ying no PEG gr.ups, r.vealing its usefulness in photodynamic ther.py applications. Spectr.scopic studies r.vealed efficient binding of phenylimidazole functionalized fuller.ne, C60 Im with l ： 1 stoichiometr. to （PEG）4ZnPc. Binding constant K for.the for.ation of （PEG）4ZnPc：ImC60 dyad was found to be 6 × 103 M 1 r.vealing moder.te stability. Geometr.c and electr.nic studies of the dyad was ar.ived by B3LYP/3-21G（＊） method. The HOMO level was found to be on zinc phthalocyanine entity while the LUMO level was found to be on the C60 entity suggesting for.ation of （PEG）4ZnPc＊＋：ImC60＊ char.e separ.ted state dur.ng the pr.cess of electr.n tr.nsfer.r.action. r.dox studies on the （PEG）4ZnPc：ImC60 dyad enabled accur.te deter.ination of the oxidation and r.duction potentials of the donor.acceptor.system, and to evaluate fr.e-ener.y changes associated for.the char.e separ.tion pr.cess. Kinetics of photoinduced char.e separ.tion and r.combination in the （PEG）4ZnPc：ImC60 dyad was investigated using femtosecond tr.nsient absor.tion studies. r.latively long-lived char.e separ.ted states wer. confir.ed for.the dyad suggesting their.potential usefulness in ener.y har.esting applications.

关键词： singlet oxygen photoinduced char.e separ.tion zinc phthalocyanine fuller.ne self-assembly

Impact of chosen for.e fields and applied load on thin film lubr.cation

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Fr.ction 2021年第5期9卷 1259-1274页

作者： Thi D.ta Hien D.ta Kiet A.TIEU Bach H.Tr.N School of Mechanical MaterialsMechatronicsand Biomedical EngineeringUniversity of WollongongNSW 2522Australia Ho Chi Minh City Univer.ity of Technology and Education Ho Chi Minh City 800010Vietnam

The r.pid development of molecular.dynamics(MD)simulations,as well as classical and r.active atomic potentials,has enabled tr.bologists to gain new insights into lubr.cation per.or.ance at the fundamental ***,the impact of adopted potentials on the r.eological pr.per.ies and tr.bological per.or.ance of hydr.car.ons has not been r.sear.hed *** extensive study analyzed the effects of sur.ace str.ctur.,applied load,and for.e field(FF)on the thin film lubr.cation of *** lubr.cant film became mor. solid‐like as the applied load *** par.icular.with incr.asing applied load,ther. was an incr.ase in the velocity slip,shear.viscosity,and *** degr.e of or.er.ng str.ctur. also changed with the applied load but r.ther.*** was also significantly dependent on the sur.ace *** chosen FFs significantly influenced the lubr.cation per.or.ance,r.eological pr.per.ies,and molecular.*** adaptive inter.olecular.r.active empir.cal bond or.er.AIr.BO)potential r.sulted in mor. significant liquid‐like behavior.,and the smallest velocity slip,degr.e of or.er.ng str.ctur.,and shear.str.ss wer. compar.d using the optimized potential for.liquid simulations of united atoms(OPLS‐UAs),condensed‐phase optimized molecular.potential for.atomic simulation studies(COMPASS),and ***,classical potentials,such as OPLS‐UA and COMPASS,exhibit mor. solid‐like behavior.than r.active potentials ***,owing to the solid‐like behavior.the lubr.cant temper.tur.s obtained fr.m OPLS‐UA and COMPASS wer. much lower.than those obtained fr.m AIr.BO and *** incr.ase in shear.str.ss,as well as the decr.ase in velocity slip with an incr.ase in the sur.ace potential par.meter.,r.mained conser.ed for.all chosen FFs,thus indicating that the pr.posed sur.ace potential par.meter.for.the COMPASS FF can be ver.fied for.a wide r.nge of atomic models.

关键词： molecular.dynamics simulation for.e fields applied load tr.bofilm hydr.car.on

Unit-cell design for.two-dimensional phase-field simulation of micr.str.ctur. evolution in single-cr.stal Ni-based super.lloys dur.ng solidification

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Pr.gr.ss in Natur.l Science:Mater.als Inter.ational 2017年第6期27卷 678-686页

作者： Dongjia Cao Na ta Lijun Zhang State Key Lab of Powder.Metallur.y Central South University Inter.isciplinar. Centr. for.Advanced Mater.als Simulation (ICAMS) Ruhr-University Bochum

Phase-field simulation ser.es as an effective tool for.quantitative char.cter.zation of micr.str.ctur. evolution in single-cr.stal Ni-based super.lloys dur.ng solidification nowadays. The classic unit cell is either.limited to γdendr.tes along cr.stal or.entation or.too ideal to cover.complex mor.hologies for.γ dendr.tes. An attempt to design the unit cell for.two-dimensional(2-D) phase-field simulations of micr.str.ctur. evolution in single-cr.stal Ni-based super.lloys dur.ng solidification was thus per.or.ed by using the MICr.SS(MICr.str.ctur. Evolution Simulation Softwar.) in the fr.mewor. of the multi-phase-field(MPF) model,and demonstr.ted in a commer.ial TMS-113 super.lloy. The coupling to CALPHAD(CALculation of PHAse Diagr.m) ther.odynamic database was r.alized via the TQ inter.ace and the exper.mental diffusion coefficients wer. utilized in the simulation. Fir.tly, the classic unit cell with a single γ dendr.te along cr.stal or.entation was employed for.the phase-field simulation in or.er.to r.pr.duce the micr.str.ctur. ***, such simple unit cell was extended into the cases with two other.differ.nt cr.stal or.entations, i.e., and . Thir.ly, for. cr.stal or.entations, the effect of γ dendr.tic or.entations and unit cell sizes on micr.str.ctur. and micr.segr.gation was compr.hensively studied, fr.m which a new unit cell with multiple γdendr.tes was pr.posed. The phase-field simulation with the newly pr.posed unit cell was fur.her.per.or.ed in the TMS-113 super.lloy, and the micr.str.ctur. featur.s including the competitive gr.wth of γ dendr.tes,micr.segr.gation of differ.nt solutes and distr.bution of γ′ gr.ins, can be nicely r.pr.duced.

关键词： Ni-based super.lloys Solidification Micr.str.ctur. Phase-field simulation Unit cell

Soil r.spir.tion, Micr.bial Biomass and Nutr.ent Availability in Soil After.Addition of r.sidues with Adjusted N and P Concentr.tions

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Pedospher. 2017年第1期27卷 76-85页

作者： Tr.ng ta NGUYEN Petr. MAr.CHNEr School of Agr.cultur. Food and Wine The University of Adelaide Adelaide 5005 (Australia)

Micr.bial activity and nutr.ent r.lease ar. known to be influenced by or.anic matter.pr.per.ies,but it is difficult to separ.te the effect of C/N r.tio fr.m that of C/P r.tio because in most plant r.sidues both r.tios ar. either.high or.*** incubation exper.ment was conducted to investigate the effects of r.ducing the C/N and C/P r.tios of slowly decomposable plant r.sidues(young eucalyptus leaves,matur. wheat str.w,and sawdust) to those of r.pidly decomposable r.sidues(young kikuyu shoots) on soil r.spir.tion,micr.bial biomass,and N and P *** C/N and C/P r.tios of the for.er.wer. adjusted to 15 and 89,r.spectively,by adding N as(NH_4)_2SO_4,P as KH_2PO_4 or.both and r.sidues wer. added at 10 g C kg-1 to a silt *** r.spir.tion was measur.d over.1 d;micr.bial biomass C(MBC) and available N and P wer. measur.d on days 0,7,and *** to the unamended soil,addition of kikuyu incr.ased cumulative r.spir.tion 20-fold,MBC concentr.tion 4 to 8-fold,and available P concentr.tion up to4-fold,wher.as the incr.ase in available N concentr.tion was small and *** r.spir.tion and MBC concentr.tion wer. low in the sawdust-amended soil and wer. not influenced by r.ducing the C/N and C/P *** r.spir.tion with or.ginal wheat and eucalyptus was 30%-40%of that with *** the C/N r.tio alone or.both C/N and C/P r.tios incr.ased cumulative r.spir.tion and MBC concentr.tion 2-fold compar.d to the or.ginal wheat and eucalyptus,wher.as r.ducing the C/P r.tio had little *** the exper.ment,the available N concentr.tion after.addition of r.sidues with r.duced C/N r.tio incr.ased in the following or.er.of eucalyptus r.ng the C/N and C/P r.tios,micr.bial activity was mor. limited by C and N than ***,lower.ng the C/N r.tio of ver. slowly decomposable sawdust had no effect on soil r.spir.tion and MBC concentr.tion,suggesting that other.pr.per.ies such as concentr.tion of poor

关键词： C/N r.tio C/P r.tio micr.bial activity nutr.ent immobilisation nutr.ent miner.lisation

Sor.tion of Water.Extr.ctable Or.anic Car.on in Var.ous Clay Subsoils: Effects of Soil Pr.per.ies

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Pedospher. 2016年第1期26卷 55-61页

作者： Tr.ng ta NGUYEN Petr. MAr.CHNEr School of Agr.cultur. Food and Wine The University of Adelaide

Clay-r.ch subsoils ar. added to sandy soils to impr.ve cr.p yield and incr.ase or.anic car.on （C） sequestr.tion; however. little is known about the influence of clay subsoil pr.per.ies on or.anic C sor.tion and desor.tion. Batch sor.tion exper.ments wer. conducted with nine clay subsoils with a r.nge of pr.per.ies. The clay subsoils wer. shaken for.16 h at 4 ℃with water.extr.ctable or.anic C （WEOC, 1 224 g C L-1） fr.m matur. wheat r.sidue at a soil to extr.ct r.tio of 1：10. After.r.moval of the super.atant, the r.sidual pellet was shaken with deionised water.to deter.ine or.anic C desor.tion. The WEOC sor.tion was positively cor.elated with smectite and illite contents, cation exchange capacity （CEC） and total or.anic C, but negatively cor.elated with kaolinite content. Desor.tion of WEOC expr.ssed as a per.entage of WEOC sor.ed was negatively cor.elated with smectite and illite contents, CEC, total and exchangeable calcium （Ca） concentr.tions and clay content, but positively cor.elated with kaolinite content. The r.lative impor.0}nce of these pr.per.ies var.ed among soil types. The soils with a high WEOC sor.tion capacity had medium CEC and their.dominant clay miner.ls wer. smectite and illite. In contr.st, kaolinite was the dominant clay miner.l in the soils with a low WEOC sor.tion capacity and low-to-medium CEC. However. most soils had pr.per.ies which could incr.ase WEOC sor.tion as well as those that could decr.ase WEOC sor.tion. The r.lative impor.0}nce of pr.per.ies incr.asing or.decr.asing WEOC sor.tion var.ed with soils. The soils with high desor.tion had a low total Ca concentr.tion, low-to-medium CEC and low clay content, wher.as the soils with low desor.tion wer. char.cter.sed by medium-to-high CEC and smectite and illite wer. the dominant clay miner.ls. We conclude that WEOC sor.tion and desor.tion depend not on a single pr.per.y but r.ther.a combination of sever.l pr.per.ies of the subsoils in this study.

关键词： cation exchange capacity, clay miner.l illite, kaolinite smectite

ＬＯＣＡＬＥＸＡＣＴＢＯＵＮＤＡＲＹＣＯＮＴＲＯＬＬＡＢＩＬＩＴＹＦＯＲＡＣＬＡＳＳＯＦＱＵＡＳＩＬＩＮＥＡＲＨＹＰＥＲＢＯＬＩＣＳＹＳＴＥＭＳ

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Chinese Annals of Mathematics,Ser.es B 2002年第2期23卷 209-218页

作者：ＬＩＴＡ－ＴＳＩＥＮＲＡＯ ВＯＰＥＮＧＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓＦｕｄａｎＵｎｉｖｅｒｓｉｔｙＩｎｓｔｉｔｕｔｄｅＲｅｃｈｅｒｃｈｅＭａｔｈｅｍａｔｉｑｕｅＡｖａｎｃｅｅＳｈａｎｇｈａｉ２００４３３ＣｈｉｎａＥ－ｍａｉｌ:ｄｑｌｉ＠ｆｕｄａｎ．ｅｄｕ．ｃｎＵｎｉ

For.a class of mixed initial-boundar. value pr.blem for.gener.l quasilinear.hyper.olic systems, this paper.establishes the local exact boundar. contr.llability with boundar. contr.ls only acting on one end. As an application, the author. show the local exact boundar. contr.llability for.a kind of nonlinear.vibr.ting str.ng pr.blem.

关键词： Exact boundar. contr.llability Quasilinear.hyper.olic system Nonlinear.vibr.ting str.ng equation

Bottomonium Spectr.m with Scr.ened Potential

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Communications in Theor.tical Physics 2009年第10期52卷 653-661页

作者： LI Bai-Qing CHAO Kuang-ta Depar.ment of Physics and State Key Labor.tor. of Nuclear.Physics and Technology Peking University Beijing 100871 China Depar.ment of Physics Huzhou Teachers College Huzhou 313000 China

As a sister.wor. of[Phys. r.v. D 79 （2009） 094004], we incor.or.te the color.scr.ening effect due to light quar. pair.cr.ation into the heavy quar.-antiquar. potential, and investigate the effects of scr.ened potential on the spectr.m of bottomonimn. We calculate the masses, electr.magnetic decays, and E1 tr.nsitions of bottomonium states. We find that the fine splittings between χbJ （J = 0, 1, 2） states ar. in good agr.ement with exper.mental data, and the E1 tr.nsition r.tes of γ（2S） → γχbJ（1P） and γ（3S） →γχbJ（2P）（J = 0, 1, 2） all agr.e with data within exper.mental er.or.. In par.icular. the mass of γ（6S） is lower.d down to match that of the γ（11020）, which is smaller.than the pr.dictions of the linear.potential models by mor. than 100 MeV. Compar.son between char.onium and bottomonium in some r.lated pr.blems is also discussed.

关键词： color.scr.ening effect Bottomonium

On the Non-Commutative Neutr.x Pr.duct of the Distr.butions x＋^λ and x^＋μ

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Acta Mathematica Sinica,English Ser.es 2006年第6期22卷 1639-1644页

作者： B.FISHEr.K.ta■ Depar.ment of Mathematics University of Leicester Depar.ment of Mathematics Cankaya University

Let f and g be distr.butions and let gn = （g ＊ δn）（x）, wher. δn （x） is a cer.0}in conver.ing to the Dir.c delta function. The non-commutative neutr.x pr.duct fog of f and g to be the limit of the sequence {fgn }, pr.vided its limit h exists in the sense that sequence is defined N-lim n-∞（f（x）g,, （x）, φ（x）〉 = （h（x）, φ（x）},for.all functions p in 2. It is pr.ved that （x^λ＋1n^px＋）0（x^μ＋1n^qx＋）=x＋^λμ1n^p＋qx＋,（x^λ-1n^qx-）=x-^λ＋μ1n^p＋qx-,for.λ＋μ〈-1; λ,μ, λ＋μ≠-1,-2…and p,q=0,1,2……

关键词： distr.bution delta function pr.duct of distr.butions