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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes f.E.Jorge A.Canal neto Departamento de fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

Reconstruction of lithofacies using a supervised Self-Organizing Map:Application in pseudo-wells based on a synthetic geologic cross-section

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Artificial Intelligence in Geosciences 2024年第1期5卷 14-26页

作者： Carreira V.R. Bijani R. Ponte-neto C.f. Departamento de Geologia e Geofísica Universidade Federal Fluminense(UFF)NiteróiBrazil Coordenação de Geofísica Observatório Nacional(ON-MCTIC)Rio de JaneiroBrazil

Recently,machine learning(ML)has been considered a powerful technological element of different society *** transform the computer into a decision maker,several sophisticated methods and algorithms are constantly created and *** geophysics,both supervised and unsupervised ML methods have dramatically contributed to the development of seismic and well-log data *** well-logging,ML algorithms are well-suited for lithologic reconstruction problems,once there is no analytical expressions for computing well-log data produced by a particular rock ***,supervised ML methods are strongly dependent on a accurate-labeled training data-set,which is not a simple task to achieve,due to data absences or *** an adequate supervision is performed,the classification outputs tend to be more accurate than unsupervised *** work presents a supervised version of a Self-Organizing Map,named as SSOM,to solve a lithologic reconstruction problem from well-log ***,we go for a more controlled problem and simulate well-log data directly from an interpreted geologic *** then define two specific training data-sets composed by density(RHOB),sonic(DT),spontaneous potential(SP)and gamma-ray(GR)logs,all simulated through a Gaussian distribution function per *** the training data-set is created,we simulate a particular pseudo-well,referred to as classification well,for defining controlled *** one comprises a training data-set with no labeled log data of the simulated fault *** the second test,we intentionally improve the training data-set with the *** bespeak the obtained results for each test,we analyze confusion matrices,logplots,accuracy and *** from very thin layer misclassifications,the SSOM provides reasonable lithologic reconstructions,especially when the improved training data-set is considered for *** set of numerical experiments shows that our SSOM is extremely

关键词： Self-Organizing Maps Supervised machine learning Synthetic well-log data Classification of lithofacies

Direct oxidation of methane at low temperature using Pt/C,Pd/C,Pt/C-ATO and Pd/C-ATO electrocatalysts prepared by sodium borohydride reduction process

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燃料化学学报 2018年第9期46卷 1137-1145页

作者： J.Nandenha E.H.fontes R.M.Piasentin f.C.fonseca A.O.neto Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SPAv.Prof.Lineu Prestes2242 Cidade UniversitáriaCEP 05508-000Sao PauloSPBrazil

The main objective of this paper was to characterize the voltammetric profiles of the Pt/C,Pt/C-ATO,Pd/C and Pd/CATO electrocatalysts and study their catalytic activities for methane oxidation in an acidic electrolyte at 25 ℃ and in a direct methane proton exchange membrane fuel cell at 80 ℃. The electrocatalysts prepared also were characterized by X-ray diffraction( XRD) and transmission electron microscopy( TEM). The diffractograms of the Pt/C and Pt/C-ATO electrocatalysts show four peaks associated with Pt face-centered cubic( fcc) structure,and the diffractograms of Pd/C and Pd/C-ATO show four peaks associated with Pd face-centered cubic( fcc) structure. for Pt/C-ATO and Pd/C-ATO,characteristic peaks of cassiterite( SnO_2) phase are observed,which are associated with Sb-doped SnO_2( ATO) used as supports for electrocatalysts. Cyclic voltammograms( CV) of all electrocatalysts after adsorption of methane show that there is a current increase during the anodic scan. However,this effect is more pronounced for Pt/C-ATO and Pd/C-ATO. This process is related to the oxidation of the adsorbed species through the bifunctional mechanism,where ATO provides oxygenated species for the oxidation of CO or HCO intermediates adsorbed in Pt or Pd sites. from in situ ATR-fTIR( Attenuated Total Reflectance-fourier Transform Infrared) experiments for all electrocatalysts prepared the formation of HCO or CO intermediates are observed,which indicates the production of carbon dioxide. Polarization curves at 80 ℃in a direct methane fuel cell( DMEfC) show that Pd/C and Pt/C electroacatalysts have superior performance to Pd/C-ATO and Pt/C-ATO in methane oxidation.

关键词： sodium borohydride reduction process Pt/C-ATO and Pd/C-ATO electrocatalysts methane oxidation acidic electrolytes polarization curves

Impact of rainfed and irrigated agriculture systems on soil carbon stock under different climate scenarios in the semi-arid region of Brazil

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Journal of Arid Land 2022年第4期14卷 359-373页

作者： André L CARVALHO Renato A ARAúJO-neto Guilherme B LYRA Carlos E P CERRI Stoécio M f MAIA Center for Agrarian Sciences Federal University of AlagoasRio Largo 57072-900Brazil Luiz de Queiroz College of Agriculture The University of Sao PauloPiracicaba 13418-900Brazil federal Institute of Alagoas Marechal Deodoro 57160-000Brazil

Understanding the dynamics of soil organic carbon(SOC) is of fundamental importance in land use and management, whether in the current researches or in future scenarios of agriculture systems considering climate change. In order to evaluate SOC stock of the three districts(Delmiro Gouveia, Pariconha, and Inhapi districts) in the semi-arid region of Brazil in rainfed and irrigated agriculture systems under different climate scenarios using the Century model, we obtained RCP4.5 and RCP8.5 climate scenarios derived from the Eta Regional Climate Model(Eta-Had GEM2-ES and Eta-MIROC5) from the National Institute for Space Research, and then input the data of bulk density, p H, soil texture, maximum temperature, minimum temperature, and rainfall into the soil and climate files of the Century model. The results of this study showed that the Eta-Had GEM2-ES model was effective in estimating air temperature in the future period. In rainfed agriculture system, SOC stock under the baseline scenario was lower than that under RCP4.5 and RCP8.5 climate scenarios, while in irrigated agriculture system, SOC stock in the almost all climate scenarios(RCP4.5 and RCP8.5) and models(Eta-Had GEM2-ES and Eta-MIROC5) will increase by 2100. The results of this study will help producers in the semi-arid region of Brazil adopt specific agriculture systems aimed at mitigating greenhouse gas emissions.

关键词： soil carbon stock agriculture systems climate scenarios Century model semi-arid region

A GIS fOR THE ANTARCTIC SPECIALLY MANAGED AREA Of ADMIRALTY BAY,KING GEORGE ISLAND,ANTARCTICA

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Geo-Spatial Information Science 2001年第2期4卷 8-14页

作者： Jefferson Cardia Simóes f.a.f.rron Matthias Braun J.Arigony neto f.E.Aquino Laboratório de Pesquisas Antrticase Glaciológicas

A GIS is proposed as a tool for the managing plan for the Antarctic specially managed area (ASMA) in Admiralty *** ASMA comprises the area considered to be within the glacial drainage basin of the ***,it includes part of SSSI No.8 adjacent to the area but outside of the glacial drainage *** stations and six refuges are located in the *** a SPOT satellite image map,the limits of the ASMA are marked and its area is re_*** consists of 362 km 2,including 186 km 2 island ice field and small cirque glaciers and 32 km 2 ice_free *** rest comprises water of the bay and a small adjacent area (8 km 2) of the Bransfield *** ASMA_GIS will consists of 12 data layers ranging from the physiographic settings to the biological and administrative *** data will be implemented into Arc/Info GIS according to the cartographic guidelines of the SCAR WG_***,five plans of information will be realised using a topographic database compiled from various sources and data.f.om the revised bathymetric chart published by the Brazilian Navy Hydrographic Survey and also including: 1) Limits of the ASMA and protected areas;2) Glaciological features (*** basin limits) and 3) Human presence (*** and historical sites).These basic GIS layers will be operational in early ***,additional data on the remaining layers (***,geology and geomorphology) will be included from published sources. The ASMA_GIS will form an important database for environmental monitoring and studies surveying temporal changes of features such as glacier front positions or bird breading sites.

关键词： Admiralty Bay managing plan environmental monitoring ASMA

All-electron ZORA triple zeta basis sets for the elements Cs-La and Hf-Rn

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Chinese Physics B 2023年第9期32卷 242-249页

作者： Antônio Canal neto francisco E.Jorge Henrique R.Cda Cruz Departamento de física Universidade Federal do Espírito Santo29075-910 VitóriaESBrazil

Segmented all-electron basis set of triple zeta valence quality plus polarization functions(TZP)for the elements of the fifth row to be used together with the zero-order regular approximation(ZORA)is carefully *** correctly describe electrons distant from atomic nuclei,the basis set is augmented with diffuse functions giving rise to a set designated as *** the ZORA-B3LYP theoretical level,these sets are used to calculate the ionization energy and mean dipole polarizability of some atoms,bond length,dissociation energy,and harmonic vibrational frequency of diatomic ***,these results are compared with the theoretical and experimental data.f.und in the *** considering that our sets are relatively compact,they are sufficiently accurate and reliable to perform property calculations involving simultaneously electrons from the inner shell and outer *** performances of the ZORA and second-order Douglas-Kroll-Hess Hamiltonians are evaluated and the results are also discussed.

关键词： TZP-ZORA and ATZP-ZORA basis sets ZORA-B3LYP method Cs-La and Hf-Rn elements atomic and molecular properties

Late Cryogenian-Ediacaran magmatism in southern Borborema Province,NE Brazil:Ages,sources,petrogenesis,and tectonic setting

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Geoscience frontiers 2023年第6期14卷 70-101页

作者： fábio Santos Pereira Herbet Conceição Maria de Lourdes Silva Rosa Moacyr Moura Marinho Colombo Celso Gaeta Tassinari João Marinho Milhomem neto Jean-Michel Lafon Programa de Pós-Graduação em Geologia e Geoquímica(PPGG) Instituto de GeociênciasUniversidade Federal do Pará(UFPA)66075-110 BelémParáBrazil Programa de Pós-Graduação em Geociências e Análise de Bacias(PGAB) Universidade Federal de Sergipe(UFS)49100-000 São CristóvãoSergipeBrazil Instituto de Geociências Universidade Federal da Bahia(UFBA)40170-290 SalvadorBahiaBrazil Instituto de Geociências Universidade de São Paulo(USP)05508-900 São PauloBrazil Laboratório de Geologia Isotópica(Pará-Iso) IG-UFPA66075-110 BelémParáBrazil

The Sergipano Orogenic System(SOS)in southern Borborema Province(NE Brazil)hosts voluminous Neoproterozoic plutonism related to the Brasiliano/Pan-African *** paper presents comprehensive whole-rock geochemical data,titanite U-Pb ages,and the first combined zircon U-Pb and Lu-Hf isotope results for plutonic rocks from the MacururéDomain to constrain their sources,petrogenesis,and tectonic *** magmatic episodes are recognized and record the evolutionary stages of the orogen.(i)Early-collisional magmatism(643–628 Ma)comprises gabbros and diorites with minor tonalites characterized by well-developed tectonic foliation and evidence of solid-state *** rocks are magnesian,high-K calc-alkaline,LILE-and LREE-enriched and provide subchondriticε_(Hf)(t)values(6.5 to4.7)and Orosirian Hf-T^(C)_(DM)model ages(1.83–1.94 Ga).Such features indicate derivation from a lithospheric mantle source metasomatized by incorporating crustal components through subduction processes prior to magma generation,possibly related to the Rhyacian Orogeny(2.20–1.96 Ga).Extensive mixing/mingling between basaltic and crust-derived magmas took place at lower crustal depths,producing coeval hybrid diorites and quartz-diorites.(ii)Syn-collisional magmatism(630–624 Ma)encompasses biotite-and muscovite-bearing granodiorites and monzogranites,preserving their structures parallel to the schistosity of the country *** rocks are leucocratic,weakly metaluminous to peraluminous,and contain abundant surmicaceous *** features and geochemical composition suggest an origin related to the partial melting of graywacke protoliths with a subordinate igneous component.(iii)Late-collisional magmatism(625–600 Ma)includes undeformed and isotropic monzonites and granodiorites,which truncate the regional *** rocks are consistently metaluminous and magnesian,showing a.f.nities with the high-K calc-alkaline to shoshonite *** element modeling with su

关键词： Brasiliano/Pan-African Orogeny Western Gondwana Zircon and titanite U-Pb dating Hf isotope data Magma source

first Late Triassic Record of a Paleoentomofauna.f.om South America(Malargüe Basin,Mendoza Province,Argentina)

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 915-924页

作者： Carsten BRAUCKMANN Oscar f.GALLEGO Norbert HAUSCHKE Rafael G.MARTINS-neto Elke GROENING Jan-M.ILGER María B.LARA Geology and Palaeontology Clausthal University of TechnologyLeibnizstrasse 10D-38678 Clausthal-ZellerfeldGermany Micropaleontology(faculty of Natural Sciences-National Northeast University) 3400 Corrientes-Argentina Palaeontology Area(Center of Applied Ecology of the Litoral-National Research Council) 3400 Corrientes-Argentina Geosciences Martin Luther University Halle-WittenbergVon-Seckendorff-Platz 3D-06120 Halle(Saale)Germany federal University from Ceara Cariri/FUNCAPPresident Brazilian Paleoarthropodological SocietyBrazil

Late Middle Triassic to early Late Triassic insects from Argentina have been previously described from the Bermejo and Cuyana Basins where they have been recovered from the Ischichuca-Los Rastros and Potrerillos-Cacheuta.f.rmations, respectively. The insect fauna discussed herein was collected during field studies in 1986/1987 from the Llantenes section （Norian to Rhaetian？ Late Triassic）, which is situated in the Malargiie Basin in southern Mendoza province. The insect remains were found in the upper part of the Llantenes section （Llantenes formation）, which is built up of two coarsening-upwards cycles reflecting a deltaic progradation of a.f.uvial into a lacustrine environment （lower part）, succeeded by repeated progradatious into a.f.oodplaindominated environment （upper part; with finds of insects, conchostracans, fish remains, plant fragments, and drifted logs）. The new finds represent the youngest Triassic insect records described from Argentina and even from South America in its entirety. There is only one contemporaneous fossil assemblage in Gondwana： in the Ciarence/Moreton Basin （Aberdare Conglomerate; Late Norian） in Australia. The new Triassic insects include an impression of an isolated Mecopterida-like wing （Mendozachorista volkheimeri gen. et sp. nov.; Mendozachoristidae fam. nov.）, coleopteran elytra of the Permosynidae （Ademosyne rosenfeldi sp. nov. and Ademosyne Uantenesensis sp. nov.） and other isolated body fragments. This new Late Triassic entomofauna.f.om Argentina is of considerable importance in the reconstruction of the biotic recovery of continental environments in Gondwana after the catastrophic mass extinction at the P/T boundary.

关键词： Mecopterida Coleoptera Late Triassic Liantenes formation Malargiie Basin Argentina

燃料电池式反应器中Pt和Pd中加入Bi用于催化乙醇发电并选择性联产醋酸盐

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燃料化学学报 2021年第10期49卷 1540-1548页

作者： Lima.f.S. fontes E.H. Nandenha J. de Souza R.f.B. neto A.O. Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SPCEP 05508-900 São PauloSPBrazil

直接乙醇燃料电池作为便携式移动电源受到越来越多的关注,如乙醇能量密度高、可再生、无毒、清洁、便于储存和运输等优点。然而,乙醇燃料电池的研究也面临一些严重问题,其中C−C键断裂是最为挑战的问题之一。近年来有报道表明,乙醇的完... 详细信息

直接乙醇燃料电池作为便携式移动电源受到越来越多的关注,如乙醇能量密度高、可再生、无毒、清洁、便于储存和运输等优点。然而,乙醇燃料电池的研究也面临一些严重问题,其中C−C键断裂是最为挑战的问题之一。近年来有报道表明,乙醇的完全氧化(包含C−C键断裂过程)并没有显示出燃料电池效率的增加,相反乙醇不完全氧化的催化剂会导致更明显的催化电流增加。同时金属Bi掺杂会对催化剂产生电子效应和几何效应并有效增加碱性体系中催化剂的活性位中心和抗CO中毒能力。因此,本工作将铋掺杂在铂和钯中制备出PtBi/C和PdBi/C作为乙醇燃料电池催化剂,同时研究Bi掺杂催化剂对乙醇燃料电池性能以及乙醇的不完全氧化产物醋酸盐的影响,为乙醇燃料电池电-化学品联产提供一定的依据。以硼氢化钠为还原剂,Vulcan XC-72(Cabot)导电炭为载体制备了Pt/C、Pd/C、PtBi/C和PdBi/C(20%质量比)炭载催化剂,其中PtBi和PdBi原子比均为95∶5。首先将金属前驱体溶于H_(2)O/异丙醇溶液(50/50,体积比)中,加入Vulcan XC-72导电炭黑充分混合,然后加入硼氢化钠在常温常压下充分反应,过滤洗涤干燥备用。其次,对所制备的催化剂进行TEM、XRD、XPS、电化学以及光谱电化学进行表征和测试。电化学、光谱电化学在三电极电解池中进行,将所制备的催化剂分散在超薄多孔电极上制备成工作电极,对电极为Pt片电极,参比电极为Ag/AgCl电极。电解液为碱性1 mol/L KOH的乙醇溶液,在电化学工作站上进行CV、LSV扫描以及在不同电位下测试溶液的ATR-fTIR谱。最后,燃料电池测试在一个面积为5 cm2的单电池上进行,阳极为2 mol/L乙醇+3 mol/L KOH溶液,流量为2 mL/min,阴极通入氧气,并研究催化剂的构成及性能对电池性能的影响。采用硼氢化钠还原法合成Pt/C、PtBi(95∶5)/C、Pd/C和PdBi(95∶5)/C。Pd/C和PdBi/C的晶体结构呈现fCC特征,Pt/C和PtBi/C的晶体结构也呈现fCC特征。XRD也揭示了铋原子对Pt晶体结构的影响。在1 mol/L KOH溶液中,异位XPS和循环伏安法显示这些金属具有较高的氧化态。透射电镜显示Pd/C有一定的纳米粒子聚集,PdBi/C有一定的有序结构。红外光谱(ATR-fTIR)结果表明,Bi效应由于吸附能力较弱,抑制了碳酸盐的生成,增加了醋酸盐的生成。由于醋酸盐优先生成,且不被碳酸盐离子毒害,PtBi/C具有最佳的电化学和DEfC性能。通过在Pt和Pd掺杂金属Bi制备具有电子调控的双金属炭载PtBi(95∶5)/C和PdBi(95∶5)/C催化剂,以增强乙醇氧化反应催化氧化过程。透射电镜(TEM)和X射线光电子能谱(XPS)结果表明,Bi含量不影响PdBi纳米颗粒的尺寸,但会影响PtBi纳米颗粒的尺寸。X射线衍射分析表明,Bi掺杂改变了Pt晶体结构中的晶格参数。此外,ATR-fTIR结果表明,碳酸盐的形成受到抑制,乙酸盐产量增加。极化曲线和功率密度曲线结果表明,PtBi/C催化剂具有更高的功率密度,几乎是Pt/C的6倍。在线性扫描伏安实验中,PtBi/C具有最高的电流密度(44 mW/cm2)和最低的起始电位(−0.6 V)。在电流-时间实验中,它也具有最高的最终电流密度。因此,在Pt和Pd中掺杂铋催化剂被证明是一种很有前途的燃料电池发电和醋酸盐的联产方法。

关键词：甲醇氧化反应 Bi掺杂电-化学品联产