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Green Chemical Engineering 2022年第3期3卷 280-287页

作者： Felipe de la Cruz-Martinez Jose A.Castro-Osma Agustin Lara-Sanchez Universidad de Castilla-La Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de Ciencias y Tecnologias QuimicasCiudad Real13071Spain Instituto de Investigaciones quimicas(IIQ) Departamento de Quimica Inorganica and Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Consejo Superior de Investigaciones Cientificas(CSIC)and University of SevillaSevilla41092Spain Universidad de Castilla-La Mancha Departamento de Quimica InorganicaOrganica y Bioquimica-Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA)Facultad de FarmaciaAlbacete02071Spain

Novel mono-and bimetallic scorpionate aluminum compounds have been designed and characterized by spec-troscopic methods.These organometallics complexes,in combination with tetrabutylammonium bromide as cocatalyst,displayed good catalytic activity for the cycloaddition of styrene oxide and CO_(2) under ambient con-ditions.Among the compounds tested,monometallic complex 3 featuring diethylamino groups showed the highest catalytic activity.This catalytic system catalyzed the formation of cyclic carbonate products from their corresponding epoxides at room temperature and 1 bar of CO_(2) pressure in the absence of a solvent in good yields and excellent selectivities.

关键词： CO_(2) Epoxides Cyclic carbonates Aluminum complexes

P-functionalized carbon nanotubes promote highly stable electrocatalysts based on Fe-phthalocyanines for oxygen reduction: Experimental and computational studies

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Journal of Energy Chemistry 2022年第9期31卷 276-290,I0008页

作者： Beatriz Martinez-Sanchez Diego Cazorla-Amors Emilia Morallon departamento de quimica Fisica and Instituto Universitario de Materiales de Alicante(IUMA)University of Alicante Ap.99.03080 AlicanteSpain Departamento de Quimica Inorganica and Instituto Universitario de Materiales de Alicante(IUMA) University of AlicanteAp.9903080 AlicanteSpain

Iron(Ⅱ) phthalocyanines(FePc) supported on functionalized nanostructured carbon materials have been studied as electrocatalysts for the oxygen reduction reaction(ORR) in an alkaline medium. Herein, two types of carbon nanotubes(CNTs) have been explored as support, Single-Walled Carbon Nanotubes and Herringbone Carbon Nanotubes(SWCNTs and h CNTs, respectively), both electrochemically modified with ortho-aminophenylphosphonic acid(2APPA), which provides phosphate axial coordinating ligands for the immobilization of FePc molecules. All the catalysts were prepared via a facile incipient wetness impregnation method. Comprehensive experimental analysis together with density functional theory(DFT) calculations has demonstrated both the importance of the five-coordinated Fe macrocycles that favor the interaction between the FePc and the carbon support, as well as the effect of the CNT structure in the ORR. FePc axial coordination provides a better dispersion, leading to higher stability and a favorable electron redistribution that also tunes the ORR performance by lowering the stability of the reaction intermediates. Interestingly, such improvement occurs with a very low content of metal(~1 wt% Fe),which is especially remarkable when h CNT support is employed. This work provides a novel strategy for the development of Fe-containing complexes as precious metal-free catalysts towards the ORR.

关键词： Carbon nanotubes Iron phthalocyanine Oxygen reduction Electrocatalysis Axial ligand

Solid-state synthesis of LnOCl/Ln_2O_3(Ln=Eu, Nd) by using chitosan and PS-co-P4VP as polymeric supports

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Journal of Rare Earths 2018年第12期36卷 1326-1332页

作者： C.Diaz D.Carrillo R.de la Campa A.Presa Soto M.L.Valenzuela departamento de quimica Facultad de Quimica Universidad de Chile departamento de quimica Organica e inorganica (IUQOEM) Facultad de Quimica Universidad de Oviedo Universidad Autonoma de Chile Facultad de Ingenieria Instituto de Ciendas Quimicas Aplicadas Inorganic Chemistry and Molecular Material Center

A series of lanthanide materials of type LnOCl or Ln2O3(Ln = Eu, Nd) were successfully prepared via a convenient and straightforward two-step procedure. Firstly, and by using chitosan and PS-co-P4 VP as polymeric supports, macromolecular complexes of type chitosan ·LnCl3and PS-co-P4 VP·LnCl3 were prepared. These macro molecular complexes were treated in solid state at 800 ℃ under air, leading to the corresponding LnOCl or Ln2O3materials(Ln = Eu, Nd) with moderate to good yields. The nature of the asprepared lanthanide materials(LnOCl and/or Ln2O3) is strongly influenced by the polymeric template(i.e.,chitosan or PS-co-P4 VP), the lanthanide salt precursor, and the polymer/lanthanide molar ratio. Thus, when chitosan · EuCl3and PS-co-P4 VP·EuCl3are used as macromolecular precursors, a mixture of crystalline phases of both EuOCl and Eu2O3are obtained. However, when chitosan· NdCl3and PS-co-P4 VP· NdCl3are used, a sole pure crystalline phase of NdOCl is obtained. The nano structured lanthanide materials were characterized by means of XRD(X-ray diffraction of powder), SEM, EDS, TEM, and HRTEM. The luminescent spectra of the asprepared EuOCI/Eu2O3mixture materials show an emission pattern whose intensity is strongly influenced by the nature of the polymeric precursor, as well as on the metal/polymer molar ratios.

关键词： EuOCl/Eu_2O_3 NdOCl Solventless method Luminescence Lanthanides Rare earths

Minimizing sperm oxidative stress using nanotechnology for breeding programs in rams

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2395-2410页

作者： Alejandro Jurado‑Campos Pedro Javier Soria‑Meneses Maria Arenas‑Moreira Carlos Alonso‑Moreno Virginia Rodriguez‑Robledo Ana Josefa Soler Jose Julian Garde Maria del Rocio Fernandez‑Santos SaBio IREC(CSIC-UCLM-JCCM) Campus UniversitarioS/N02071 AlbaceteSpain. Departamento de Quimica Inorganica Organica Y Bioquimica‑Centro de Innovacion en Quimica Avanzada(ORFEO‑CINQA)Facultad de FarmaciaUniversidad de Castilla-La Mancha02008 AlbaceteSpain. Centro Regional de Investigacion Biomedicas Unidad nanoDrugUniversidad de Castilla-La Mancha02008 AlbaceteSpain. Facultad de Farmacia Universidad de Castilla La Mancha02071 AlbaceteSpain.

Background Artificial insemination(AI)is a routine breeding technology in animal reproduction.Nevertheless,the temperature-sensitive nature and short fertile lifespan of ram sperm samples hamper its use in AI.In this sense,nanotechnology is an interesting tool to improve sperm protection due to the development of nanomaterials for AI,which could be used as delivery vehicles.In this work,we explored the feasibility of vitamin E nanoemulsion(NE)for improving sperm quality during transport.Results With the aim of evaluating this proposal,ejaculates of 7 mature rams of Manchega breed were collected by artificial vagina and extended to 60×10^(6)spz/mL in AndromedR.Samples containing control and NE(12 mmol/L)with and without exogenous oxidative stress(100μmol/L Fe2+/ascorbate)were stored at 22 and 15℃and motility(CASA),viability(YO-PRO/PI),acrosomal integrity(PNA-FITC/PI),mitochondrial membrane potential(Mitotracker deep Red 633),lipoperoxidation(C11 BODIPY 581/591),intracellular reactive oxygen species(ROS)production and DNA status(SCSAR)monitored during 96 h.Our results show that NE could be used to maintain ram spermatozoa during transport at 15 and 22℃for up to 96 h,with no appreciable loss of kinematic and physiological characteristics of freshly collected samples.Conclusions The storage of ram spermatozoa in liquid form for 2-5 d with vitamin E nanoemulsions may lead more flexibility to breeders in AI programs.In view of the potential and high versatility of these nanodevices,further studies are being carried out to assess the proposed sperm preservation medium on fertility after artificial insemination.

关键词： Breeding technology Nanoemulsions Nanotechnology Sperm oxidative stress Vitamin E

Editorial for a special issue on graphene and 2D alternative materials:From preparation to potential applications

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Nano Materials Science 2022年第1期4卷 1-2页

作者： Pablo Ares Felix Zamora departamento de Fisica de la Materia Condensada and Condensed Matter Physics Center(IFIMAC) Universidad Autonoma de Madrid Madrid28049Spain Departamento de Quimica Inorganica Condensed Matter Physics Center(IFIMAC)and Institute for Advanced Research in Chemical Sciences(IAdChem)Universidad Autonoma de MadridMadrid28049Spain Instituto Madrileno de Estudios Avanzados en Nanociencia(IMdeA-Nanociencia) CantoblancoMadrid28049Spain

The isolation of graphene and subsequent studies showed that obtaining atomically thin crystalline sheets was feasible and possessed extraordinary properties.This result opened the door to an entirely new family of materials known as two-dimensional or 2D materials.Research in this field is intense:the emergence of new 2D materials,the properties of their combinations and the ability of graphene to reinvent itself,showing novel and exciting properties,make it likely that this field will continue to be one of the leading topics of materials science and condensed matter physics.

关键词： preparation entirely crystalline

S-doped carbon aerogels/GO composites as oxygen reduction catalysts

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Journal of Energy Chemistry 2016年第2期25卷 234-243页

作者： Mykola Seredych Krisztina László Enrique Rodríguez-Castellón Teresa J.Bandosz The City College of New York and The Graduate Center of CUNY Department of Chemistry 160 Convent Avenue New York NY 10031 USA department of Physical Chemistry and Materials Science Budapest University of Technology and Economics Budapest 1521 Hungary Departamento de Quimica Inorganica Universidad de Malaga Malaga 29071 Spain

Composites of carbon aerogel and graphite oxide（GO） were synthesized using a self-assembly method based on dispersive forces. Their surface was modified by treatment in hydrogen sulfide at 650 and800 ℃. The samples obtained were characterized by adsorption of nitrogen, TA-MS, XPS, potentiometric titration, and HRTEM and tested as catalysts for oxygen reduction reactions（ORR） in an alkaline medium.The synergistic effect of the composite（electrical conductivity, porosity and surface chemistry） leads to a good ORR catalytic activity. The onset potential for the composite of carbon aerogel heated at 800 ℃ is shifted to a more positive value and the number of electron transfer was 2e-at the potential 0.68 V versus RHE and it increased to 4e-with an increase in the negative values of the potential. An excellent tolerance to methanol crossover was also recorded.

关键词： Oxygen reduction reaction Carbon aerogel/GO composites Porosity Surface chemistry Specific interactions

Filling the Gaps to Solve the Extensin Puzzle

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Molecular Plant 2018年第5期11卷 645-658页

作者： Eliana Marzol Cecilia Borassi Mauro Bringas Ana Sede Diana Rosa Rodriguez Garcia Luciana Capece Jose M. Estevez Fundacion Instituto Leloir and Instituto de Investigaciones Bioquimicas de Buenos Aires (IIBBA-CO.NICEr) Avenida Patricias Argentinas 435 Buenos AiresCP C1405BWE Argentina Departamento de Quimica Inorganica Analitica y Quimica Fisica Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires (INQUIMAE-CONICET)Buenos Aires CP C1428EGA Argentina Instituto de Investigaciones en Ingenierfa Genetica y Biologia Molecular Dr. Hector Torres (INGEBI-CONICET) Vuelta de Obligado 2490 Buenos Aires C1428ADNArgentina

Extensins （EXTs） are highly repetitive plant O-glycoproteins that require several post-translational modifi- cations （PTMs） to become functional in plant cell walls. First, they are hydroxylated on contiguous proline residues; then they are O-glycosylated on hydroxyproline and serine. After secretion into the apoplast, O-glycosylated EXTs form a tridimensional network organized by inter- and intra-Tyr linkages. Recent studies have made significant progress in the identification of the enzymatic machinery required to process EXTs, which includes prolyl 4-hydroxylases, glycosyltransferases, papain-type cysteine endopeptidases, and peroxidases. EXTs are abundant in plant tissues and are particularly important in rapidly expanding root hairs and pollen tubes, which grow in a polar manner. Small changes in EXT PTMs affect fastgrowing cells, although the molecular mechanisms underlying this regulation are unknown. In this review, we highlight recent advances in our understanding of EXT modifications throughout the secretory pathway, EXT assembly in cell walls, and possible sensing mechanisms involving the Catharanthus roseus cell surface sensor receptor-like kinases located at the interface between the apoplast and the cytoplasmic side of the plasma membrane.

关键词： Arabidopsis thaliana cysteine endopeptidases extensins glycosyltransferases peroxidases prolyl 4-hydroxylases

Hadron resonances as rovibrational states

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Chinese Physics C 2021年第8期45卷 99-104页

作者： Douglas L.Bernardo Cristiano C.Bastos Antonio C.Pavao departamento de quimica Fundamental Universidade Federal de PernambucoRecife50740-540Brazil departamento de quimica Universidade Federal Rural de PernambucoRecife52171-900Brazil

A rovibrational model,including anharmonic,centrifugal,and Coriolis corrections,is used to calculate π,K,N,and ∑ orbital and radial resonances.The four orbital excitations of the n meson correspond to the/?(1235),ti2(1670),63(2030),and π4(2250)resonances.Its first four radial excitations correspond to the π(1300),π(1800),π(2070),and 7t(2360)resonances.The orbital excitations of the K meson are interpreted as the K_(1)(1270),K_(2)(1770),K_(3)(2320),and K_(4)(2500)resonances;its radial excitations correspond to the K(1460)and K(1830)resonances.The N orbital excitations are identified with the N(1520),N(1680),N(2190),N(2220),and N(2600)resonances.The first four radial excitations of the N family correspond to the N(1440),N(1880),N(2100),and N(2300)resonances.The orbital excitations of the ∑ baryon are associated with the ∑(1670),∑(1915),∑(2100),and ∑(2250)resonances,whereas its radial excitations are identified with the ∑(1660),∑(1770),and ∑(1880)resonances.The proposed rovibrational model calculations show a good agreement with the corresponding experimental values and allow for the prediction of hadron resonances,thereby proving to be useful for the interpretation of excited hadron spectra.

关键词： excited hadron spectrum orbital and radial resonances rovibrational states

Quantitative Electrophilicity Measures

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物理化学学报 2018年第6期34卷 662-674页

作者： GONZáLEZ Marco Martínez CáRdeNAS Carlos RODRíGUEZ Juan I. LIU Shubin HEIDAR-ZAdeH Farnaz MIRANDA-QUINTANA Ramón Alain AYERS Paul W. Laboratory of Computational and Theoretical Chemistry Faculty of Chemistry University of Havana Havana 10400 Cuba. departamento de quimica and Centro de Quimica Universidade de Coimbra 3004-535 Coimbra Portugal. departamento de Fisica Fac

Quantitative correlation of several theoretical electrophilicity measures over different families of organic compounds are examined relative to the experimental values of Mayr et al.Notably,the ability to predict these values accurately will help to elucidate the reactivity and selectivity trends observed in charge-transfer reactions.A crucial advantage of this theoretical approach is that itprovides this information without the need of experiments,which are often demanding and time-consuming.Here,two different types of electrophilicity measures were analyzed.First,models derived from conceptual density functional theory(c-DFT),including Parr's original proposal and further generalizations of this index,are investigated.For instance,the approaches of Gázquez et al.and Chamorro et al.are considered,whereby it is possible to distinguish between processes in which a molecule gains or loses electrons.Further,we also explored two novel electrophilicity definitions.On one hand,the potential of environmental perturbations to affect electron incorporation into a system is analyzed in terms of recent developments in c-DFT.These studies highlight the importance of considering the molecular surroundings when a consistent description of chemical reactivity is needed.On the other hand,we test a new definition of electrophilicity that is free from inconsistencies(so-called thermodynamic electrophilicity).This approach is based on Parr's pioneering insights,though it corrects issues present in the standard working expression for the calculation of electrophilicity.Additionally,we use machine-learning tools(i.e.,symbolic regression) to identify the models that best fit the experimental values.In this way,the best possible description of the electrophilicity values in terms of different electronic structure quantities is obtained.Overall,this straightforward approach enables one to obtain good correlations between the theoretical and experimental quantities by using the simple,yet powerful,interpretative advantage of c-DFT method

关键词： Electrophilicity Conceptual density functional theory Symbolic regression Genetic programming Grammatical evolution

Reactivity of Indoles through the Eyes of a Charge-Transfer Partitioning Analysis

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物理化学学报 2018年第6期34卷 692-698页

作者： OROZCO-VALENCIA Ulises GáZQUEZ José L. VELA Alberto departamento de quimica Centro de Investigacion y de Estudios Avanzados Av. Instituto Politecnico Nacional 2508 Colonia San Pedro Zacatenco Ciudad de Mexico 07360 Mexico. departamento de quimica Universidad Autonoma Metropolitana-Iztapalapa

A global and local charge transfer partitioning model,based on the cornerstone theory developed by Robert G.Parr and Robert G.Pearson,which introduces two charge transfer channels(one for accepting electrons(electrophilic) and another for donating(nucleophilic)),is applied to the reaction of a set of indoles with 4,6-dinitrobenzofuroxan.The global analysis indicates that the prevalent electron transfer mechanism in the reaction is a nucleophilic one on the indoles,i.e.,the indoles under consideration transfer electrons to 4,6-dinitrobenzofuroxan.Evaluating the reactivity descriptorswith exchange-correlation functionals including exact exchange(global hybrids) yields slightly better correlations than those obtained with generalized gradient-approximated functionals;however,the trends are preserved.Comparing the trend obtained with the number of electrons donated by the indoles,and predicted by the partitioning model,with that observed experimentally based on the measured rate constants,we propose that the number of electrons transferred through this channel can be used as a nucleophilicity scale to order the reactivity of indoles towards 4,6-dinitrobenzofuroxan.This approach to obtain reactivity scales has the advantage of depending on the intrinsic properties of the two reacting species;therefore,it opens the possibility that the same group of molecules may show different reactivity trends depending on the species with which they are reacting.The local model allows systematic incorporation of the reactive atoms based on the their decreasing condensed Fukui functions,and the correlations obtained by increasing the number of reactive atoms participating in the local analysis of the transferred nucleophilic charge improve,reaching an optimal correlation,which in the present case indicates keeping three atoms from the indoles and two from 4,6-dinitrobenzofuroxan.The atoms selected by this procedure provide valuable information about the local reactivity of the indoles.We further show that this information about the m

关键词： Chemical reactivity Conceptual DFT Charge transfer Nucleophilicity Indoles Transition state prediction