From ZIF-8@Al2O3Composites to Self-Supported ZIF-8 One-Dimensional Superstructures

Efficient preparation of composite materials consisting of ZIF-8 nanocrystals embedded inside the channels of macroporous anodic aluminum oxide membranes is reported. 1-D self-supported ZIF-8 superstructures are recovered through matrix dissolution

Polychlorinated trityl radicals for dynamic nuclear polarization: the role of chlorine nuclei

Polychlorinated trityl radicals bearing carboxylate substituents are water soluble persistent radicals that can be used for dynamic nuclear polarization. In contrast to other trityl radicals, the polarization mechanism differs from the classical solid effect. DFT calculations performed to rationalize this behaviour support the hypothesis that polarization is transferred from the unpaired electron to chlorine nuclei and from these to carbon by spin diffusion. The marked differences observed between neutral and anionic forms of the radical will be discussed

SANÇÕES ADMINISTRATIVAS APLICADAS NA AVIAÇÃO: UMA ANÁLISE DOS PRINCÍPIOS APLICÁVEIS AOS PROCESSOS ADMINISTRATIVOS NA AVIAÇÃO

TCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Jurídicas. Direito.O presente trabalho busca averiguar se o processo administrativo sancionatório na aviação cumpre os princípios da lei dos processos administrativos (lei 9.784/99). O estudo se faz relevante pois é um campo ainda pouco estudado e precisa ser tratado com seriedade já que é uma das formas de demonstração do ius puniendi estatal. O objetivo do trabalho é verificar se os processos administrativos que resultam em multas para os operadores de aeronaves cumprem os princípios constitucionais e legais. Sendo assim, será desenvolvido um estudo sobre os aspectos que envolvem as sanções administrativas. Além disso, será trabalhado sobre os limites da presunção de veracidade da Administração Pública, bem como será investigada a relação entre os princípios da lei dos processos administrativos (lei 9.784/99) com os processos administrativos em estudo. Ao final, será apresentada uma análise de dois processos administrativos relacionados ao tema em discussão. Nessa análise é possível identificar algumas falhas da Administração Pública, tanto na concepção do processo administrativo em questão (normas aplicadas através de Portarias) quanto no desenvolvimento com relação aos princípios que deveriam ser observados. Percebe-se, por fim, a necessidade de aperfeiçoar o processo administrativo no seio da Junta de Julgamento de Aeronáutica, órgão responsável por todo o desenvolvimento desse processo. Essa pesquisa serve para apontar apenas alguns dos aspectos mais relevantes que necessitam uma posterior atenção e um número maior de estudos na área para que haja uma evolução nesse ramo do Direito

Silacyclopentadiènes porteurs de radicaux aminoxyles (synthèse, structure électronique et propriétés magnétiques)

MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

Architectures supramoléculaires à structures ouvertes fondées sur la liaison hydrogène (élaboration, caractérisation structurale et propriétés de sorption)

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Extended H-bond networks based on guanidinium H-donors and [Zr(A) 4]4- H-acceptor units: modulation of the assemblage and guest accessible volume by chemical design (A = oxalate, dihydrobenzoquinonate, chloranilate)

Supramolecular assemblages between three different [Zr(A)4] 4- metallotectons (A stands for oxalate, Ox2-; dihydrobenzoquinonate, DBQ2-; or chloranilate CA2-) and three different guanidinium cation analogues (guanidinium, H-Guan+; 2-amino-imidazolium, H-AIm+; and N,N-dimethylguanidinium, H-DmG +) have been envisioned to investigate how the anionic and/or cationic building-block characteristics influence the connectivity and/or the dimensionality of frameworks based on charge-assisted H-bonds. Added to the benchmark material, {(H-Guan)4[Zr(Ox)4]}, (1), the crystal structures of six architectures of formula {(H-AIm)4[Zr(Ox) 4]}·5H2O (2), {(H-DmG)4[Zr(Ox) 4]}·0.5H2O (3), {(H-Guan)4[Zr(DBQ) 4]}·1.5H2O (4), {(H-Guan)4[Zr(CA) 4]}·5.85H2O (5), {(H-AIm)4[Zr(CA) 4]}·H2O (6), and {K2(H 2O)3(H-DmG)2[Zr(DBQ)4]} ·H2O (7) have been characterized. While 1 consists of a two dimensional (2D) H-bonded network with compact structure, four out of the six supramolecular architectures (2-7) form 3D H-bonded networks, and three of these materials (namely, 2, 4 and 5) present open-framework architectures with solvent accessible voids ranging from 8 to 13%. Compounds 4-7 are the first examples of H-bonded frameworks constructed from [Zr(DBQ)4] 4- and [Zr(CA)4]4- metallotectons. © 2013 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.This work was supported by the French Ministry for Education and Research by a grant for G. M. and by the CNRS (Centre National de la Recherche Scientifique).Peer Reviewe

Metal-radical chains based on polychlorotriphenylmethyl radicals: synthesis, structure, and magnetic properties

7 páginas, 7 figuras, 3 tablas.-- et al.We report the synthesis, crystal structures, and magnetic properties of two new metal-radical chains built up from a new class of organic radical-based ligands, the polychlorinated triphenylmethyl (PTM) radicals. Crystal structures of two new 1D coordination polymers, [Cu2(PTMDC)2(py)5(EtOH)]·3EtOH (1) and [Co2(PTMDC)2(DMF)2(H2O)6]·5DMF (2) (where PTMDC is a PTM radical functionalized with two carboxylic groups), show similar chain-like structures, in which each of the PTMDC radicals are connecting two Cu(II) or Co(II) metal ions. Therefore, from a magnetic point of view, both structures describe a magnetic chain model based on the PTMDC-M(II) unit. In this manuscript, the magnetic exchange coupling constants between both metal ions and the bridging PTM radicals have been determined. In both cases, the temperature dependence of the magnetic susceptibility reveals antiferromagnetic exchange coupling constants between the PTMDC radicals and Cu(II) (J/kB = −42 K) and Co(II) (J/kB = −14.6 K) ions based on the exchange Hamiltonian H = −J∑SAiSAi+1.This work was supported by DGI, Spain (Project MAT2003-04699 and MAT2009-13977-C03-03) CIBER-BBN an initiative of ISCIII, and DGR Catalonia (Project 2001SGR00362). N.D. thank the Ministerio de Innovación y Ciencia for a JdC contract. D.M. thank the Ministerio de Ciencia y Tecnología for a RyC contract.Peer reviewe

Bis(hexafluoroacetylacetonato)manganese(II) complex of 1,1-dimethyl-2,5-bis-(3-N-tert-butyl-N-phenylaminoxyl) -3,4-diphenylsilolacyclopentadiene.

Crystals of the 1st bis-adduct of 2,5-bis[3-(tert-butylaminoxyl)phenyl]-1,1-dimethyl-3,4-diphenylsilole with bis(hexafluoroacetylacetonato)manganese(II) are monoclinic, space group P21/n; Z = 2. The Mn atom lies on a crystallog. inversion center and is bound to two chelating hexafluoroacetylacetonate ligands and two monodentate nitroxide groups in a distorted octahedral configuration. The silole ligands present a propeller-like arrangement of the benzene rings around the Si-contg. five-membered ring. The dihedral angles between the complexed nitroxides and the benzene rings to which they are bound are smaller than those found in the free ligand

Efficient growth of sub-micrometric MOF crystals inside the channels of AAO membranes

International audienceA dynamic step-by-step methodology has been implemented to grow the HKUST-1 porous coordination polymer inside commercial anodic aluminium oxide membranes. Efficient crystal growth is achieved from the membrane inner walls and over the whole membrane thickness when copper acetate colloidal suspensions and benzene tricarboxylic acid solutions are forced to flow through the membrane. Sorption properties of the HKUST-1 embedded in membranes show selectivity for CO2 over CO, CH4, O2 and N2 similar to the bulk material