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On Integrable Roots in Split Lie Triple Systems

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Acta Mathematica Sinica,English Series 2009年第11期25卷 1759-1774页

作者： A.J.CALdeRóN MARTíN departamento de Matemáticas Universidad de Cádiz

We focus on the notion of an integrable root in the framework of split Lie triple systems T with a coherent 0-root space. As a main result, it is shown that if T has all its nonzero roots integrable, then its standard embedding is a split Lie algebra having all its nonzero roots integrable. As a consequence, a local finiteness theorem for split Lie triple systems, saying that whenever all nonzero roots of T are integrable then T is locally finite, is stated. Finally, a classification theorem for split simple Lie triple systems having all its nonzero roots integrable is given.

关键词： Lie triple system root split Lie algebra classification theory

FINITELY GENERATED COMMUTATIVE ARCHimedeAN SEMIGROUPS

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Acta Mathematica Scientia 2003年第4期23卷 503-511页

作者： J.C.Rosales J.I.García-García departamento de Algebra Universidad de Granada E-18071 Granada EspanaDepartamento de Algebra Universidad de Granada E-18071 Granada Espana

In this work commutative Archimedean finitely generated semigroups axe characterized in terms of ideal extensions.

关键词： Commutative semigroups Archimedean

Envelopes of Commutative Rings

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Acta Mathematica Sinica,English Series 2012年第3期28卷 561-580页

作者： Rafael PARRA Manuel SAORIN departamento de Clculo. Escuela Bsica Facultad de Ingeniería Universidad de los Andes departamento de Matemticas Universidad de Murcia

Given a significative class F of commutative rings, we study the precise conditions under which a commutative ring R has an S-envelope. A full answer is obtained when F is the class of fields, semisimple commutative rings or integral domains. When .F is the class of Noetherian rings, we give a full answer when the Krull dimension of R is zero and when the envelope is required to be epimorphic. The general problem is reduced to identifying the class of non-Noetherian rings having a monomorphic Noetherian envelope, which we conjecture is the empty class.

关键词： Noetherian ring envelope local ring artinian ring Krull dimension

Gas-phase electrocatalytic conversion of CO_2 to chemicals on sputtered Cu and Cu–C catalysts electrodes

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Journal of Energy Chemistry 2019年第4期28卷 46-53页

作者： N.Gutiérrez-Guerra J.A.González J.C.Serrano-Ruiz E.López-Fernández J.L.Valverde A.de Lucas-Consuegra departamento de Ingeniería Química Facultad de Ciencias y Tecnologías Químicas Universidad de Castilla-La Mancha Instituto Regional de Investigación Científica Aplicada (IRICA) and departamento de Física Aplicada Universidad de Castilla-La Mancha departamento de Ingeniería Universidad Loyola Andalucía

A novel gas-phase electrocatalytic cell containing a low-temperature proton exchange membrane(PEM)was developed to electrochemically convert CO_2into organic *** different Cu-based cathode catalysts(Cu and Cu–C)were prepared by physical vapor deposition method(sputtering)and subsequently employed for the gas-phase electroreduction of CO_2at different temperatures(70–90°C).The prepared electrodes Cu and Cu–C were characterized by X-ray diffraction(XRD),X-ray photoemission spectroscopy(XPS)and scanning electron microscopy(SEM).As revealed,Cu is partially oxidized on the surface of the samples and the Cu and Cu–C cathodic catalysts were comprised of a porous,continuous,and homogeneous film with nanocrystalline Cu with a grain size of 16 and 8 nm,*** influence of the applied current and temperature on the electro-catalytic activity and selectivity of these materials was *** the two investigated electrodes,the pure Cu catalyst film showed the highest CO_2specific electrocatalytic reduction rates and higher selectivity to methanol formation compared to the Cu–C electrode,which was attributed to the higher particle size of the former and lower Cu O/Cu *** obtained results show potential interest for the possible use of electrical renewable energy for the transformation of CO_2into valuable products using low metal loading Cu based electrodes(0.5 mg Cu cm^(-2))prepared by sputtering.

关键词： CO_2 valorization Electro-reduction Cu catalyst PEM Selectivity Methanol production

A Remark about the Orlicz-Pettis Theorem and the Statistical Convergence

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Acta Mathematica Sinica,English Series 2010年第2期26卷 305-310页

作者： A.AIZPURU M.NICASIO-LLACH F.RAMBLA-BARRENO departamento de Matemticas Universidad de Cdiz

In this paper we obtain a new version of the Orlicz-Pettis theorem by using statistical convergence. To obtain this result we prove a theorem of uniform convergence on matrices related to the statistical convergence.

关键词： statistical convergence summability Orlicz-Pettis theorem

A decomposition Theorem for G-Groups

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Acta Mathematica Sinica,English Series 2010年第3期26卷 405-418页

作者： I.LIZASOAIN departamento de Matemticas Universidad Publica de Navarra Campus de Arrosada

Some classical results about linear representations of a finite group G have been also proved for representations of G on non-abelian groups （G-groups）. In this paper we establish a decomposition theorem for irreducible G-groups which expresses a suitable irreducible G-group as a tensor product of two projective G-groups in a similar way to the celebrated theorem of Clifford for linear representations. Moreover, we study the non-abelian minimal normal subgroups of G in which this decomposition is possible.

关键词： representations of groups permutation groups semisimple groups primitive groups

Testing carbonate chemostratigraphy across differentiated ancient shallow-platform environments(Early Kimmeridgian,S Iberia)

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Geoscience Frontiers 2019年第6期10卷 2203-2218页

作者： Rute Coimbra Beatriz Marques Federico Oloriz GeoBioTec Departamento de GeocienciasUniversidade de AveiroPortugal MARE Departamento de Ciencias da TerraUniversidade de CoimbraPortugal Faculdade de Ciencias e Tecnologia Universidade Nova de LisboaPortugal departamento de Estratigrafia y Palaeontologia Universidad de GranadaSpain

Shallow-platform settings with marked differences in paleoplatform bottom physiography influence the degree of connection with oceanic waters and overall circulation patterns,even when sharing the same palaeoclimatic *** Kimmeridgian shallow-marine settings have been explored to test the sensitivity and reliability of carbonate chemostratigraphy to detect such *** integrated overview of the obtained elemental trends depicted four major facies,shared along specific stratigraphic intervals of both depositional *** obliterated original geochemical signals only throughout the siliciclastics-rich interval,corresponding to the most landward *** the remaining facies,elemental features could be attributed to the differential action of forcing mechanisms operating along the south-Iberian paleomargin during Kimmeridgian *** highest degree of continental influence can be recognized by a strong relationship between Fe and Mn for the most proximal setting,which fades out along the mixed carbonate-fine siliciclastic rhythmic deposition in more open settings.A characteristic geochemical signature of progressively more positiveδ^(13)C values and significantly higher Sr content is identified for the interval dominated by biogenic sponge *** a local response is related to local forcing by upwelling in the surroundings of a coral *** geochemical signature of a hydrothermal origin can be clearly differentiated from the influence of mere terrigenous ***,the decoupling of Fe and Mn along marginal settings is the clue to detecting major events of palaeogeographic *** temporal variations in Mg content along both studied sections are attributed to tectonic activity influencing nearshore/coastal water *** integrating chemostratigraphic information and complementary evidence,the palaeoenvironmental mechanisms promoting differentiated sedimentary records along ancient subtropical,shallow

关键词： Palaeoenvironment Carbonate chemostratigraphy Shallow-water carbonates Diagenesis Kimmeridgian

A Survey of the Homotopy Properties of Inclusion of Certain Types of Configuration Spaces into the Cartesian Product

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1223-1246页

作者： Daciberg Lima GONCALVES John GUASCHI departamento de Matematica IME-USPRua do Matao 1010CEP:05508-090Sao PauloSPBrazil Normandie Universite UNICAENLaboratoire de Mathematiques Nicolas Oresme UMR CNRS 6139CS 1403214032 Caen Cedex 5France

Let X be a topological *** this survey the authors consider several types of configuration spaces,namely,the classical(usual)configuration spaces F_n(X)and D_n(X),the orbit configuration spaces F_n^G(X)and F_n^G(X)/S_nwith respect to a free action of a group G on X,and the graph configuration spaces F_n~Γ(X)and F_n~Γ(X)/H,whereΓis a graph and H is a suitable subgroup of the symmetric group S_*** ordered configuration spaces F_n(X),F_n^G(X),F_n~Γ(X)are all subsets of the n-fold Cartesian product ∏_1~nX of X with itself,and satisfy F_n^G(X)?F_n(X)?F_n~Γ(X)?∏_1~*** A denotes one of these configuration spaces,the authors analyse the difference between A and ∏_1~nXfrom a topological and homotopical point of *** principal results known in the literature concern the usual configuration *** authors are particularly interested in the homomorphism on the level of the homotopy groups of the spaces induced by the inclusionι:A-→∏_1~nX,the homotopy type of the homotopy fibre I_ιof the mapιvia certain constructions on various spaces that depend on X,and the long exact sequence in homotopy of the fibration involving I_ιand arising from the inclusionι.In this respect,if X is either a surface without boundary,in particular if X is the 2-sphere or the real projective plane,or a space whose universal covering is contractible,or an orbit space S^k/Gof the k-dimensional sphere by a free action of a Lie group G,the authors present recent results obtained by themselves for the first case,and in collaboration with Golasi′nski for the second and third *** authors also briefly indicate some older results relative to the homotopy of these spaces that are related to the problems of *** order to motivate various questions,for the remaining types of configuration spaces,a few of their basic properties are described and proved.A list of open questions and problems is given at the end of the paper.

关键词： Configuration space Equivariant configuration space Fibration Homotopy fibre K(π,1)space Braid groups

Distribution of the related weevil species Sitophilus oryzae and S. zeamais in Brazil

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Insect Science 2013年第6期20卷 763-770页

作者： Alberto S. Correa Luiz Orlando de Oliveira Lucas S. Braga Raul Narciso C. Guedes departamento de Entomologia Universidade Federal de Vicosa Vicosa Brazil departamento de Bioquimica e Biologia Molecular Universidade Federal de Vicosa Vicosa Brazil

The genus Sitophilus （Coleoptera： Curculionidae） encompasses species of great economic importance as stored grain pests worldwide. Among these species, the maize and the rice weevils （Sitophilus zeamais and Sitophilus oryzae, respectively） are partic- ularly important in warmer climates. These two weevils exhibit closely morphological and ecological resemblance making difficult their proper identification and recognition of their distribution in grain-producing regions. Both species are recorded in South America and particularly in Brazil, but their respective distribution and prevalence were not yet assessed in the region. Therefore, several insect samples throughout Brazil were collected and subjected to morphological identification using male genitalia and also using molec- ular identification with species-specific primers designed for clear recognition of both the species. The primers were designed for the specific amplification of a gene fragment of the cytochrome oxidase subunit I, which exhibited high specificity during our prelimi- nary experiments with insects from six populations of known species （either S. zeamais or S. oryzae）. Both identification strategies provided the same results indicating preva- lence of the maize weevil S. zeamais throughout the country. Two hypotheses may explain such prevalence：（i） the likely host preference ofS. zeamais for maize because this is the most cultivated cereal in Brazil, and （ii） the prevalence ofS. zeamais in tropical regions as compared with S. oryzae, which is more disseminated in subtropical and temperate regions.

关键词： cytochrome oxidase subunit I distribution maize weevil rice weevil South America