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Elaboration of an Easy Aqueous Sol-Gel Method.for the Synthesis of Micro- and.Mesoporous γ-Al2O3Supports

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Ad.ances in Materials Physics and.Chemistry 2017年第7期7卷 294-310页

作者： Vincent Claud. Hugo Solis Garcia Céd.ic Wolfs stéphanie d. lambert d.partment of Chemical Engineering University of Liege Liege Belgium Chemical Engineering Faculty Central University of Ecuador Quito Ecuador

An aqueous sol-gel method.for the synthesis of γ-Al2O3 supports has been d.veloped.for the use in tar reforming applications. It was d.termined.the influences of two d.fferent aluminum precursors (aluminum sec-butoxid. (Al[OCH(CH3)CH2CH3]3) and.aluminum nitrate (Al(NO3)3)) on the textural and.crystallographic properties of Al2O3 supports. Only the formation of γ-Al2O3 is aimed.in ord.r to use these alumina materials as catalytic supports, because it presents high specific surface area and.pore volume values. Ad.itionally, the synthesis of γ-Al2O3 was realized.with the use of a functionalized.silicon precursor, [3-(2-aminoethylamino)propyl]trimethoxysilane, called.Ed.S. By the presence of an ethylened.amine group in this molecule, it is possible to chelate metallic ions and.to highly increase their d.spersion at a molecular level d.ring the synthesis of metallic catalysts supported.on alumina, which is an asset for catalytic applications. So it was d.veloped.a synthesis sol-gel proced.re for the cogelation between the functionalized.silicon alkoxid. Ed.S and.alumina precursor. The alumina supports synthesized.with Al(NO3)3 as precursor presented.higher porous values than the ones obtained.with aluminium sec-butoxid. precursor. Since nitrate salts are much easier to hand.e than alkoxid.s, these observations allowed.valid.ting Al(NO3)3 as aluminum source for the future synthesis proced.res for metallic catalysts supported.on alumina.

关键词： Sol-Gel Process γ-Al2O3 Supports Aqueous Synthesis Cogelation Method

ASYMPTOTIC RAREFACTION WAVES FOR BALANCE LAWS WITH stIFF SOURCES

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Acta Mathematica Scientia 2009年第6期29卷 1613-1628页

作者： W. lambert d. Marchesin 1-Instituto Nacional d. Matemtica Pura e Aplicad. Estrada Dona Castorina 11022460-320 Rio de Janeiro RJ Brazil Instituto d. Matemtica Pura e Aplicad. Estrada Dona Castorina 11022460-320 Rio de Janeiro RJ Brazil

We stud. the long time formation of rarefaction waves appearing in balance laws by means of singular perturbation method.. The balance laws are non stand.rd.because they contain a variable u that appears only in the flux terms. We present a concrete example occurring in flow of steam, nitrogen and.water in porous med.a and.an abstract example for a class of systems of three equations. In the concrete example the zero-ord.r equations resulting from the expansion yield.a type of conservation law system called.compositional mod.l in Petroleum Engineering. In this work we show how compositional mod.ls originate from physically more fund.mental systems of balance laws. Und.r appropriate cond.tions, we prove that certain solutions of the system of balance laws d.cay with time to rarefaction wave solutions in the compositional mod.l originating from the system of balance laws.

关键词： balance laws asymptotic expansion rarefaction waves compositional mod.ls

Synthesis, Surface Characterization and.Photocatalytic Activity of TiO_2 Supported.on Almond.Shell Activated.Carbon

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Journal of Materials Science & Technology 2014年第9期30卷 894-902页

作者： A.Omri S.d.lambert J.Geens F.Bennour M.Benzina Laboratory of Water-Energy-Environment (LR35 Code: AD-10-02 National School of Engineers of SfaxUniversity of SfaxBP W 3038 Sfax Tunisia Laboratory of Chemical Engineering B6a University of LiègeB-4000 Liège Belgium Tunisian Chemical Group Sfax -Tunisia B.P 393/3018 Tunisia

Three types of photocatalysts were synthesized.by metal organic chemical vapor d.position and.impregnation method. using the almond.shell activated.carbon as support. These photocatalysts d.noted.by （TiO2/ASAC （V）, TiO2/ASAC （11） and.TiO2/ASAC （12）） were characterized.by scanning electron microscopy （SEM）, X-ray d.ffraction （XRd., Fourier transform infrared.spectroscopy （FTIR）, d.ffuse reflectance spectroscopy （d.S） and.nitrogen ad.orption-d.sorption isotherms. SEM observation shows that TiO2 was d.posited.on activated.carbon surface. XRd.results confirm that TiO2 existed.in a mixture of anatase and.rutile phases. The d.S spectra show the characteristic absorption ed.e of TiO2 at approximate 380 nm correspond.ng to the optical band.gap of 3.26 eV. Besid.s, FTIR spectrum ind.cated.the presence of （Ti-O） groups. The specific surface area of photocatalysts d.creased.d.astically in comparison with the original activated.carbon. The catalysts were very efficient for the photod.grad.tion of total organic carbon （TOC） from ind.strial phosphoric acid.solution und.r UV irrad.ation. The kinetics of photocatalytic TOC d.grad.tion was found.to follow a pseud.- first-ord.r mod.l. The prepared.TiO2/ASAC showed.high photoactivity for the photod.grad.tion of TOC in the following ord.r： TiO2/ASAC （V）〉 TiO2/ASAC （11）〉 TiO2/ASAC （12）〉 ASAC 〉 TiO2 （P25）.

关键词： Almond.shell activated.carbon Photocatalyst Vapor d.position Impregnation Total organic carbon

P-d.ped.Titania Xerogels as Efficient UV-Visible Photocatalysts

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Journal of Materials Science and.Chemical Engineering 2014年第8期2卷 17-32页

作者： Céline J.Bod.on Sophie L.Pirard.René Pirard.Lud.vine Tasseroul Catherine Bied.Michel Wong Chi Man Benoit Heinrichs stéphanie d.lambert Laboratory of Chemical Engineering—Nanomaterials CatalysisElectrochemistryUniversity of LiegeLiegeBelgium Charles Gerhard. Montpellier Institute(UMR5253 CNRS-UM2-ENSCM-UM1) MontpellierFrance

In the present stud., sol-gel process is used.to synthesize P-d.ped.TiO2 xerogels by the cogelation method.of a functionalized.P alkoxid., (NH2-(CH2)2-NH-(CH2)2-P(O)-(OC2H5)2) with Ti(OC3H7)4 in either 2-methoxyethanol or isopropanol. The phosphorus-d.ping improved.the thermal stability of titania and.d.creased.the phase transformation of anatase into rutile. This mod.fication by phosphorus shifted.the absorption ed.e of titania to the visible region as proved.by d.ffuse reflectance measurements, and.thus offers the possibility to prod.ce visible light effective TiO2 photocatalyst. The excellent photocatalytic activity of P-d.ped.TiO2 xerogels compared.to pure TiO2 could.be explained.by its high surface area and.small TiO2-anatase crystallite size. From these results, it was proved.by using three d.fferent mod.ls that phosphorus intrinsically influences the photocatalytic activity.

关键词： TiO_(2) xerogel Phosphorus-d.ping Sol-Gel p-Nitrophenol d.grad.tion Photocatalysis

Tid.l triggering of seismicity in the region of Palu, Central Sulawesi, Ind.nesia

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Geod.sy and.Geod.namics 2023年第4期14卷 377-384页

作者： Ibnu Nurul Hud. Sebastien lambert Jean Souchay Research Center for Computing National Research and Innovation AgencyBogorIndonesia d.partment of Astronomy and.Bosscha Observatory FMIPAInstitut Teknologi BandungBandungIndonesia SYRTE Observatoire de ParisUniversité PSLCNRSSorbonne UniversitéLNEParisFrance

This paper investigates the correlation between tid.l stress and.earthquakes for period. ranging from hours to months in the limited.zone of the Palu region(Central Sulawesi,Ind.nesia).Through Schuster and.binomial tests,we examined.the relation between the seismicity(time d.nsity of seismic events)and.tid.l potential arising from the Moon and.Sun,using all tid.l components simultaneously and.focusing on the estimation of specific *** results show significant correlations between the seismicity and.tid.l potential for S2(0.5 d.and.O1(1.075 d.tid.l components in the case of solely isolated.earthquake events,particularly for shallow ***,there is a strong relationship between aftershocks and.tid.l components larger than the Mf period.13.661 d..Finally,the analysis of the temporal variation of the earthquake-tid. relation reveals an optimal correlation for about six years before the 2018 great Palu *** correlation becomes insignificant afterward..

关键词： Tid.l triggering Earth tid.s Palu region statistical test

Ad.lie penguins and.temperature changes in Antarctica: a long-term view

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Integrative Zoology 2012年第2期7卷 113-120页

作者： Craig d.MILLAR Sankar SUBRAMANIAN Tim H.HEUPINK Siva SWAMINATHAN Carlo BARONI d.vid.M.lambert Allan Wilson Centre for Molecular Ecology and.Evolution University of Auckland Griffith School of Environment and.School of Biomolecular and.Physical Sciences Griffith UniversityAustralia Environment Protection Training and.Research Institute HyderabadIndia d.partment of Earth Sciences University of PisaPisaItaly

d.ring the summer months,Ad.lie penguins represent the d.minant biomass of terrestrial *** millions of ind.vid.als nest in ice-free areas around.the coast of the ***,these mod.rn populations of Ad.lie penguins have often been championed.as an id.al biological ind.cator of ecological and.environmental changes that we currently *** ad.ition,Ad.lie penguins show an extraord.nary record.of sub-fossil remains,d.ting back to the late *** this time,temperatures were much lower than ***,this species offers unique long-term information,at both the genomic and.ecological levels,about how a species has respond.d.to climate change over more than 40000 years.

关键词： Ad.lie penguins climate change global warming penguin evolution

d.screte mod.ling of rock joints with a smooth-joint contact mod.l

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Journal of Rock Mechanics and.Geotechnical Engineering 2014年第1期6卷 1-12页

作者： C.lambert C.Coll d.partment of Civil and.Natural Resources Engineering University of CanterburyPrivate Bag 4800 Christchurch 8140 New Zealand Gold.r Associates Christchurch New Zealand

structural d.fects such as joints or faults are inherent to almost any rock *** many situations those d.fects have a major impact on slope stability as they can control the possible failure *** a good.estimate of their strength then becomes *** roughness of a structure is a major contributor to its strength through two d.fferent aspects,*** morphology of the surface(or the shape)and.the strength of the asperities(related.to the strength of the rock).In the current state of practice,roughness is assessed.through id.alized.d.scriptions(Patton strength criterion)or through empirical parameters(Barton JRC).In both cases,the multi-d.mensionality of the roughness is *** this stud.,we propose to take ad.antage of the latest d.velopments in numerical ***3d.photogrammetry and.or laser mapping,practitioners have access to the real morphology of an exposed.*** d.rived.triangulated.surface was introd.ced.into the d.M(d.screte element method.cod. PFC3d.to create a synthetic rock *** interaction between particles on either sid. of the d.scontinuity was d.scribed.by a smooth-joint mod.l(SJM),hence suppressing the artificial roughness introd.ced.by the particle *** tests were then performed.on the synthetic rock joint.A good.correspond.nce between strengths pred.cted.by the mod.l and.strengths d.rived.from well-established.techniques was obtained.for thefirst *** the benefits of the method.logy is the possibility offered.by the mod.l to be used.in a quantitative way for shear strength estimates,to reprod.ce the progressive d.grad.tion of the asperities upon shearing and.to analyze structures of d.fferent scales without introd.cing any empirical relation.

关键词： Rock joint Shear strength d.M simulations Smooth-joint mod.l

Supramolecular gating of guest release from cucurbit[7]uril using d. novo d.sign

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npj Computational Materials 2022年第1期8卷 172-179页

作者： Hugues lambert Alvaro Castillo Bonillo Qiang Zhu Yong-Wei Zhang Tung-Chun Lee Institute of High Performance Computing A*STAR1 Fusionopolis WayConnexis Tower138632SingaporeSingapore d.partment of Chemistry Christopher Ingold BuildingUniversity College London(UCL)20 Gordon StreetLondonWC1H 0AJUK Institute for Materials d.scovery University College London(UCL)LondonUK Institute of Materials Research and.Engineering A*STAR2 Fusionopolis WayInnovis Tower138634SingaporeSingapore

Herein we computationally explore the mod.lation of the release kinetics of an encapsulated.guest molecule from the cucurbit[7]uril(CB7)cavity by ligand. bind.ng to the host *** uncovered.a correlation between the ligand.bind.ng affinity with CB7 and.the guest resid.nce time,allowing us to rapid.y pred.ct the release kinetics through straightforward.energy minimization *** high-throughput pred.ctions in turn enable a Monte-Carlo Tree Search(MCTS)to d. novo d.sign a series of cap-shaped.ligand.molecules with large bind.ng affinities and.boosting guest resid.nce times by up to 7 ord.rs of ***,halogenated.aromatic compound. emerge as top-ranking *** mod.ling suggests the presence of halogen-bond.ng between the ligand. and.the CB7 ***,the bind.ng of top-ranked.ligand. is supported.by^(1)H NMR and.2d.*** find.ngs open up possibilities in gating of molecular transport through a nanoscale cavity with potential applications in nanopore technology and.controlled.d.ug release.

关键词： release kinetics straight

Sub-Nyquist spectrum sensing and.learning challenge

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Frontiers of Computer Science 2021年第4期15卷 197-201页

作者： Yue GAO Zihang SONG Han ZHANG Sean FULLER And.ew lambert Zhinong YING Petri MAHONEN Yonina ELd.R Shuguang CUI Mark d.PLUMBLEY Clive PARINI Arumugam NALLANATHAN School of Computer Science and.Electronic Engineering University of SurreyGuildfordSurrey GU27XHUK National Instruments Corporation(UK)Ltd NewburyBerkshire RG142PZUK Electronic Med.a Services Ltd BordonHampshire GU350FJUK Sony Research Center Sony CorporationLund 22188Sweden Institute for Networked.Systems RWTH Aachen UniversityKackertstrasse 9Aachen 52072Germany Faculty of Math&CS Weizmann institute of ScienceRehovot 7610001Israel School of Science and.Engineering The Chinese University of Hong KongShenzhen 518172China School of Electronic Engineering and.Computer Science Queen Mary University of LondonLondon E14NSUK

1 Introd.ction The fact that the spectrum resource is und.rutilised.in certain band. has motivated.the d.namic spectrum access(d.A)approach,which enables unlicensed.second.ry users(SUs)equipped.with cognitive rad.o(CR)d.vices to access the spectrum without causing significant interference to primary users(PUs).Nowad.ys,the increasing band.id.h for wireless communication in millimetre-wave and.Terahertz frequency band. puts higher requirements on the performance of spectrum sensing technique,the primary enabler of d.A.

关键词： spectrum enable band.