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Effect of tungsten oxide on ceria nanorods to support copper species as CO oxidation catalysts

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Journal of Rare Earths 2021年第1期39卷 43-50,I0002页

作者： Yu'nan Li Lin gan Rui Si Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials and School of Material Science and EngineeringHubei UniversityWuhan 430062China Zhangjiang Laboratory Shanghai Synchrotron Radiation FacilityShanghai 201204China

In this work,tungsten oxide with different concentrations(0,0.4 at%,2.0 at%and 3.2 at%)was introduced to the ceria nanorods via a deposition-precipitation(DP)approach,and copper species of ca.10 at%were sequentially anchored onto the modified ceria support by a similar DP *** aim of the study was to investigate the effect of the amount of tungsten oxide(0,0.4 at%,2.0 at%,and 3.2 at%)modifier on the copper-ceria catalysts for CO oxidation reaction and shed light on the structure-activity *** the aids of multiple characterization techniques including N2 adsorption,high-resolution transmission electron microscopy(HRTEM),powder X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),and temperature-programmed reduction by hydrogen(H2-TPR)in combination with the catalytic performance for CO oxidation reaction,it is found that the copper-ceria samples maintain the crystal structure of the fluorite fcc CeO2 phase with the same nanorod-like morphology with the introduction of tungsten oxide,while the textural properties(the surface area,pore volume and pore size)of ceria support and copper-ceria catalysts are changed,and the oxidation states of copper and tungsten are kept the same as Cu2+and W6+before and after the reaction,but the introduction of tungsten oxide(WO3)significantly changes the metal-support interaction(transfer the CuOx clusters to Cu-[Ox]-Ce species),which delivers to impair the catalytic activity of copper-ceria catalysts for CO oxidation reaction.

关键词： Copper catalyst Ceria Tungsten oxide CO oxidation Structure-activity relationship Rare earths

Second-order phase correction of NMR spectra acquired using linear frequency-sweeps

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Magnetic Resonance Letters 2022年第1期2卷 1-8,I0002页

作者： Zhehong gan Ivan Hung National High Magnetic Field Laboratory 1800 East Paul Dirac DriveTallahasseeFL32310USA

NMR spectra acquired with experiments using frequency-sweeps such as the wide-band uniform-rate smooth truncation(WURST)spin-echo and Carr-Purcell-Meiboom-Gill(CPMG)sequences cannot be absorptively phased by using only conventional zerothand first-order phase *** of phase correction up to the secondorder is described for obtaining absorptive spectra,which have more desirable line shapes and noise properties than magnitude *** relationship of the second-order phase to the parameters of frequency sweeps is *** second-order phasing in the frequency-domain is equivalent to a point spread in the time-domain *** application of second-order phase correction is demonstrated with a wideline 35Cl CPMG spikelet spectrum.

关键词： Second-order phase Noise Line shape Absorptive Dispersive Frequency sweep CHIRP WURST Adiabatic Broadband CPMG Spin-echo Wideline ^(35)Cl

Maximal-minimal correlation atoms algorithm for sparse recovery

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Journal of Systems Engineering and Electronics 2013年第4期24卷 579-585页

作者： Wei gan Luping Xu Hua Zhang School of Electronic Engineering Xidian University

A new iterative algorithm is proposed to reconstruct an unknown sparse signal from a set of projected measurements. Unlike existing greedy pursuit methods which only consider the atoms having the highest correlation with the residual signal, the proposed algorithm not only considers the higher correlation atoms but also reserves the lower correlation atoms with the residual signal. In the lower correlation atoms, only a few are correct which usually impact the reconstructive performance and decide the reconstruction dynamic range of greedy pursuit methods. The others are redundant. In order to avoid redundant atoms impacting the reconstructive accuracy, the Bayesian pursuit algorithm is used to eliminate them. Simulation results show that the proposed algorithm can improve the reconstructive dynamic range and the reconstructive accuracy. Furthermore, better noise immunity compared with the existing greedy pursuit methods can be obtained.

关键词： compressive sensing (CS) correlation atom Bayesian hypothesis sparse reconstruction.

An Impulsive Heating Model for the Evolution of Coronal Loops

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 608-616页

作者： Li Feng Wei-Qun gan Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 Max Planck Institute for Solar System Research Max-Planck-Str. 2 37191 Katlenburg-LindauGermany

It was suggested by Parker that the solar corona is heated by many small energy release events generally called microflares or nanoflares. More and more observations showed flows and intensity variations in nonflaring loops. Both theories and observations have indicated that the heating of coronal loops should actually be unsteady. Using SOLFTM （Solar Flux Tube Model）, we investigate the hydrodynamics of coronal loops undergoing different manners of impulsive heating with the same total energy deposition. The half length of the loops is 110 Mm, a typical length of active region loops. We divide the loops into two categories： loops that experience catastrophic cooling and loops that do not. It is found that when the nanoflare heating sources are in the coronal part, the loops are in non-catastrophic-cooling state and their evolutions are similar. When the heating is localized below the transition region, the loops evolve in quite different ways. It is shown that with increasing number of heating pulses and inter-pulse time, the catastrophic cooling is weakened, delayed, or even disappears altogether.

关键词： hydrodynamics -- Sun corona -- Sun transition region

Aniline Induced Domino Ring Contraction Process on the Rim of an Open-Cage Fullerene with Carbonyl, Imino and lactone Moieties

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Chinese Journal of Chemistry 2014年第8期32卷 819-821页

作者： Shuming Liu Liangbing gan Beijing National Laboratory for Molecular Sciences CAS Key Laboratory for Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100080China Key Laboratory of Bioorganic Chemistry and Molecular Engineering of the Ministry of Education College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 200032China Key Laboratory of Small Organic Molecule of Handan College of ChemistryChemical Engineering and MaterialsHandan CollegeHandanHebei 056005China

Functional groups on the rim of open-cage fullerenes usually exhibit different reactivity from those in classical organic molecules due to the unique spherical structure of *** present work shows a sequence of lactone opening,imino hydrolysis,aminal formation and imine formation processes during the reaction of aniline with the open-cage compound 1 with functional groups including lactone on the rim of the *** crystal X-ray diffraction analysis confirmed the structure of the product.

关键词： fullerene open-cage fullerene ring contraction molecular container

On Proof of the C^1 Stability Conjecture

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Acta Mathematica Sinica,English Series 2005年第3期21卷 533-540页

作者： Yong ZHANG Shao Bo gan School of Mathematical Sciences Soochow University Suzhou 215006 P. R. China School of Mathematical Sciences Peking University Beijing 100084 P. R. China

It seems that in Mane＇s proof of the C^1 Ω-stability conjecture containing in the famous paper which published in I. H. E. S. （1988）, there exists a deficiency in the main lemma which says that for f ∈F^1 （M） there exists a dominated splitting TMPi（f） =Ei^s the direlf sum of E and F Fi^u（O 〈 i 〈 dim M） such that if Ei^s is contracting, then Fi^u is expanding. In the first part of the paper, we give a proof to fill up this deficiency. In the last part of the paper, we, under a weak assumption, prove a result that seems to be useful in the study of dynamics in some other stability context.

关键词： The C^1 stability conjecture Dominated splitting Shadowing property Axiom A No-cycle condition

A Study of Overseas Reception of Mo Yan's Red Sorghum

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学术界 2018年第8期 249-258页

作者： gan Lu School of Foreign languages Hubei University for Nationalities Enshi 445000

Translation of literary works is the beginning of cross-cultural *** Yan's novels attract more and more attention of foreign academy and general readers,and they have set a model for other Chinese literary works to be accepted in foreign countries. The reception of R ed Sorghum in other countries lies in the appreciation of its artistic features,analysis of its folk lore,discussion of its masculinity and femininity and its influence upon foreign literature.

关键词： Mo Yan Red Sorghum translation overseas reception

The effect of Compton scattering on gamma-ray spectra of the 2005 January 20 flare

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Research in Astronomy and Astrophysics 2012年第10期12卷 1439-1450页

作者： Wei Chen Wei-Qun gan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory ChineseAcademy of Sciences Nanjing 210008 China

Gamma-ray spectroscopy provides a wealth of information about acceler- ated particles in solar flares, as well as the ambient medium with which these energetic particles interact. The neutron capture line （2.223 MeV）, the strongest in the solar gamma-ray spectrum, forms in the deep atmosphere. The energy of these photons can be reduced via Compton scattering. With the fully relativistic GEANT4 toolkit, we have carried out Monte Carlo simulations of the transport of a neutron capture line in solar flares, and applied them to the flare that occurred on 2005 January 20 （X7.1/2B）, one of the most powerful gamma-ray flares observed by RHESSI during the 23rd solar cycle. By comparing the fitting results of different models with and without Compton scattering of the neutron capture line, we find that when including the Compton scat- tering for the neutron capture line, the observed gamma-ray spectrum can be repro- duced by a population of accelerated particles with a very hard spectrum （s ≤ 2.3）. The Compton effect of a 2.223 MeV line on the spectra is therefore proven to be sig- nificant, which influences the time evolution of the neutron capture line flux as well. The study also suggests that the mean vertical depth for neutron capture in hydrogen for this event is about 8 g cm-2.

关键词： Sun: flares -- Sun: gamma-rays -- scattering: Compton scattering

Simulation of anchor chain based on lumped mass method

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Theoretical & Applied Mechanics Letters 2023年第4期13卷 311-319页

作者： Xiaobin Jiang Jian gan Shiyang Teng Merchant Marine College Shanghai Maritime UniversityShanghai 201306China

In order to develop a anchoring operation simulation system and improve safety during anchoring operations,a relatively accurate mathematical model of anchoring operations needs to be *** this paper,the stress condition of anchor chain under environmental and subsea geological conditions is further studied and the stress condition of anchor chain is analyzed based on the previous *** this paper,a quasi-static model based on catenary method is used as the basis of dynamic analysis,and the dynamic model of anchor chain is established based on the concentrated mass method,which fully considers the influence of anchor chain weight,hydrodynamic force,ocean current and interaction with the *** fourth-order Runge Kutta method was used to solve the model numerically,and a calculation procedure was *** accuracy of the model was verified by comparing the calculated results with the experimental results,indicating that the constructed anchor chain dynamics model has a high accuracy.

关键词： Lump mass method Anchor chain Dynamic analysis