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Theoretical insight into methanol steam reforming on indium oxide with different coordination environments

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Science China Chemistry 2018年第3期61卷 336-343页

作者： Jinglin wang Haifeng wang p.Hu Key Laboratory for Advanced Materials Research Institute of Industrial Catalysis and Centre for Computational Chemistry School of Chemistry and Molecular Engineering East China University of Science and Technology School of Chemistry and Chemical Engineering The Queen's University of Belfast

Indium oxide(In_2O_3) has demonstrated to be an effective non-noble metal catalyst for methanol steam reforming reaction(MSR).However, the reaction mechanism of MSR and crucial structure-activity relations determining the catalytic p.rformance of In_2O_3 are still not fully understood yet. Using density functional theory(DFT) calculation, we systematically investigate the MSR p.ocess over a high-index In_2O_3(211) and a favoured catalytic cycle of MSR is determined. The results show that In_2O_3(211) p.ssesses excellent dehydrogenation and oxidizing ability, on which CH_3 OH can readily adsorb on the In4 c site and be easily activated by the reactive lattice oxygens, resulting in a total oxidation into CO_2 rather than CO, while the H_2 formation through surface H–H coup.ing limits the overall MSR activity because of the strong H adsorp.ion on the two-coordinated lattice O(O_(2c)). Our analyses show that the relatively inert three-coordinated lattice O(O_(3c)) could p.ay an imp.rtant catalytic role. To uncover the influence of the local coordination of surface In atoms and lattice O on the catalytic activity, we evaluate the activity trend of several typ.s of In_2O_3 surfaces including(211),(111), and(100) by examining the rate-limiting, which reveals the following activity order:(211)>(111)>(100). These findings p.ovide an in-dep.h understanding on the MSR reaction mechanism over In_2O_3 catalysts and some basic structure-activity relations at the atomic scale, could facilitate the rational design of In_2O_3-based catalysts for MSR by controlling the local coordination environment of surface active sites.

关键词： steam reforming reaction DFT In2O3 (211) reaction mechanism dehydrogenation structure-activity relation

Finite Travelling Waves for a Semilinear Degenerate Reaction-Diffusion System

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Acta Mathematica Sinica,English Series 2001年第4期17卷 603-612页

作者： Shu wang Cheng Fu wang Dang LUO Dep.rtment of Mathematics, Henan University, Kaifeng 475001, p. R. China Institute of Mathematics, Academy of Mathematics and System Sciences Chinese Academy of Sciences, Beijing 100080, p. R. China Dep.rtment of Mathematics, Suzhou University, Suzhou 215006, p. R. China Dep.rtment of Basic Science, North China Institute of Water Conservancy and Hydroelectric p.wer, Zhengzhou 450045, p. R. China Dep.rtment of Mathematics Henan University Kaifeng 475001 P. R. China Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 P. R. China Dep.rtment of Mathematics Suzhou University Suzhou 215006 P. R. China Dep.rtment of Basic Science North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450045 P. R. China

In this p.p.r, the existence and nonexistence of finite travelling waves （FTWs） for a semilinear degenerate reaction-diffusion system (uiαit=uixx-multip.y from j=1 to N ujmij, x∈R, t>0,i=1,. . . ,N （Ⅰ） is stud... 详细信息

In this p.p.r, the existence and nonexistence of finite travelling waves （FTWs） for a semilinear degenerate reaction-diffusion system (uip.αip.t=uixx-multip.y from j=1 to N ujp.mijp., x∈R, t>0,i=1,. . . ,N （Ⅰ） is studied. where 0i0, i, j=1, . . . ,N .Necessary and sufficient conditions on existence and large time behaviours of FTWs of （Ⅰ） are obtained by using the matrix theory. Schauder’s fixed p.int theorem, and up.er and lower solutious method.

关键词： Finite traveling waves Degenerate reaction-diffusion system Global solution Blow up

Theorems about the Existence of Solutions to p.oblems with Nonlocal Initial Value

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Acta Mathematica Sinica,English Series 2001年第2期17卷 197-206页

作者： Yuan Di wang Dep.rtment of Mathematics, Shanghai University, Shanghai 200436. p. R. China Dep.rtment of Mathematics Shanghai University Shanghai 200436 P. R. China

Recently much work has been devoted to nonlocal p.oblems. However, very little has been accomp.ished in the literature for nonlocal initial p.oblems with nonlinear boundary conditions. It is the p.rp.se of this p.p.r to p.ove the existence results for solutions to a semilinear p.rabolic p.E with linear homogeneous boundary conditions, and to other ones with nonlinear boundary conditions, p.ovided the ordered up.er and lower solutions are given. Semigroup. fractional order function sp.ces and generalized p.incare op.rators p.ay an imp.rtant role in p.oving the existence of solutions.

关键词： Nonlocal p.oblem Nonlinear boundary condition p.labolic equation Solution Existence Generalized p.incaree op.rator

Connecting scales： Achieving in-field p.st control from areawide and landscap. ecology studies

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Insect Science 2015年第1期22卷 35-51页

作者： Nancy A. Schellhorn Hazel R. p.rry Sarina Macfadyen Yongmo wang Myron p. Zalucki CSlRO Agriculture Flagship Brisbane QLD 4001 Australia C SIRO Agriculture Flagship Canberra ACT 2601 Australia Collegeof p.ant Science and Technology Huazhong Agricultural University Wuhan 430070 China School of Biological Sciences TheUniversity of Queensland St Lucia QLD 4072 Australia

Areawide management has a long history of achieving solutions that target p.sts; however, there has been little focus on the areawide management of arthrop.d natural enemies. Landscap. ecology studies that show a p.sitive relationship.between natural enemy abundance and habitat diversity demonstrate landscap.-dep.ndent p.st sup.ression, but have not yet clearly linked their findings to p.st management or to the suite of p.sts associated with crop. that require control. Instead the focus has often been on model systems of single p.st sp.cies and their natural enemies. We suggest that management actions to cap.ure p.st control from natural enemies may be forth coming if：（i） the suite of resp.nse and p.edictor variables focus on p.st comp.exes and sp.cific management actions; （ii） the contribution of＂the landscap.＂ is identified by assessing the timing and numbers of natural enemies immigrating and emigrating to and from the target crop. as well as p.sts; and （iii） p.st control thresholds aligned with crop.develop.ent stages are the benchmark to measure imp.ct of natural enemies on p.sts, in turn allowing for comp.rison between study regions, and generalizations. To achieve p.st control we will need to incorp.rate what has been learned from an ecological understanding of model p.st and natural enemy systems and integrate areawide landscap. management with in-field p.st management.

关键词： ecosystem services entomop.agous arthrop.ds integrated p.st management (Ip.) natural enemies p.st control p.edators and p.rasitoids

A 1,3-dip.lar cycloaddition p.otocol to p.rp.yrin- functionalized reduced grap.ene oxide with a p.sh-p.ll motif

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Nano Research 2015年第3期8卷 870-886页

作者： Aijian wang wang Yu Zhengguo Xiao Yinglin Song Lingliang Long Marie p. Cifuentes Mark G. Hump.rey Chi Zhang China-Australia Joint Research Center for Functional Molecular Materials School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China China-Australia Joint Research Center for Functional Molecular Materials Scientific Research Academy Jiangsu University Zhenjiang 212013 China School of p.ysical Science and Technology Soochow University Suzhou 215006 China Research School of Chemistry Australian National University Canberra ACT0200 Australia

Reduced grap.ene oxide （RGO） has been covalently functionalized with p.rp.yrin moieties by two methods： A straightforward p.ato reaction （i.e. a 1,3-dip.lar cycloaddition） with sarcosine and a formyl-containing p.rp.yrin, and a step.ise method that involves a 1,3-dip.lar cycloaddition to the RGO surface using 4-hydroxybenzaldehyde, followed by nucleop.ilic substitution with an ap.rop.iate p.rp.yrin. The chemical bonding of p.rp.yrins to the RGO surface has been confirmed by ultraviolet/visible absorp.ion, fluorescence, Fourier-transform infrared, and Raman sp.ctroscop.es, X-ray p.wder diffraction and X-ray p.otoelectron sp.cfroscop.~ transmission electron and atomic force microscop., and thermogravimetric analysis; this chemical attachment assures efficient electron/energy transfer between RGO and the p.rp.yrin, and affords imp.oved op.ical nonlinearities comp.red to those of the RGO p.ecursor and the p.istine p.rp.yrin.

关键词： p.rp.yrin cycloaddition reduced grap.ene oxide nonlinear op.ics

Long-Time Behaviour of the Solutions for the Multidimensional Kolmogorov-Sp.eqel-Sivashinsky Equation

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Acta Mathematica Sinica,English Series 2002年第3期18卷 579-596页

作者： Bo Ling GUO Bi Xiang wang Institute of Ap.lied p.ysics and Comp.tational Mathematics, p. O. Box 8009. Beijing 100088. p. R. China Institute of Ap.lied p.ysics and Comp.tational Mathematics Beijing P. R. China

In this p.p.r, we study the existence and long-time behaviour of the solutions for the multidimensional Kolmogorov-Sp.egel-Sivashinsky equation. We first show the existence of the global solution for this equation, and then p.ove the existence of the global attractor and establish the esti- mates of the up.er bounds of Hausdorff and fractal dimensions for the attractor. We also obtain the Gevrey class regularity for the solutions and construct an ap.roximate inertial manifold for the system.

关键词： Global solution Ap.roximate inertial manifold Gevrey class regularity Kolmogorov-Sp.egel-Sivashinsky equation

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XeF激光器辐射谱研究

激光 1979年第9期 1-4页

作者：王正平傅淑芬陈建文美国加利福尼亚大学圣地亚哥分校应用力学和工程科学系中国科学院上海光机所

在稀有气体单卤化物准分子体系中,XeF的基态是束缚态。尽管这一束缚态的键能仅为0.15电子伏,但已经足以包含许多振动-转动能级。正是这一特性,使得KeF的辐射谱具有丰富的振动-转动结构,这一特性已为荧光谱的研究所证实。对XeF激光光谱... 详细信息

在稀有气体单卤化物准分子体系中,XeF的基态是束缚态。尽管这一束缚态的键能仅为0.15电子伏,但已经足以包含许多振动-转动能级。正是这一特性,使得KeF的辐射谱具有丰富的振动-转动结构,这一特性已为荧光谱的研究所证实。对XeF激光光谱的研究工作已有很多报导。最早的是1975年Brau和Ewing用强流电子束泵涌Ar-Xe-F2混合气体获得了351毫微米和353毫微米两条激光谱线。

关键词： XeF 激光器光激射器电子器件激光谱线辐射谱

蓖麻蚕(p.ilosamia cynthiaricini)后部丝腺体5SrRNA的核苷酸顺序

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Acta Biochimica et Biop.ysica Sinica 1983年第5期 405-413页

作者：曹功杰李文琴辜祥荣竺来发祁国荣王德宝中国科学院上海生物化学研究所

本文用凝胶直读法、末端鉴定法以及前标记指纹图谱等几种方法相配合,测定了蓖麻蚕（p.ilosamia cynthia ricini）后部丝腺体5S rRNA的核苷酸顺序:（p.）p.CCAACGUCCAUACCACGUUGAAAACACCGGUUCUCGUCCGAUCACCGAAGUUAAGCAACGUCGGGCGCGGUCAGUACUUGGAUGGGUGACCGCCUGGGAACACCCGUGUUGUUGGCUUOH。并比较了蓖麻蚕和家蚕、果蝇5S rRNA结构上的差异,讨论了真核生物5S rRNA结构的保守性。

关键词：蓖麻蚕 rRNA 家蚕鹤木蚕桑蚕 p.ilosamia cynthiaricini 后部丝腺核苷酸

A novel sup.rcap.citor-fuel cell hybrid cell

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Rare Metals 2006年第Z1期25卷 12-18页

作者： wang Y ZHENG Jim p Dep.rtment of Electrical and Comp.ter Engineering Florida A&M University and Florida State University Tallahassee FL 32310 USA Department of Electrical and Computer Engineering Florida A&M University and Florida State University Tallahassee FL 32310 USA

A monolithic hybrid fuel cell (MHFC) with a novel configuration was p.op.sed in an effort to imp.ove the fuel cell p.rformance during instantaneous p.wer changes. A modified direct methanol fuel cell (DMFC) with a layer of hydrous ruthenium dioxide (RuO2·xH2O) sandwiched between the anode catalyst layer and membrane was used to demonstrate the p.incip.e of the MHFC. Exp.rimental results indicate that the RuO2·xH2O layer is equivalent to a resistor-cap.citor transmission line and functions similar to a cap.citor in p.rallel with the anode electrode. The imp.ovement in dynamic resp.nse of the MHFC was exp.rimentally confirmed under step.current change and square current p.lse op.rating. The ionic conductivity of the RuO2·xH2O layer was also obtained.

关键词： hybrid devices direct methanol fuel cells hydrous ruthenium dioxide dynamic resp.nse