917 resultados para Arquitectura teoría s.I a.C.-I


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The vibrational structure of C---H stretching states in gas-phase cyclobutene was studied using FTIR spectroscopy in the range 700–9000 cm−1. The structure was modelled using two effective vibrational Hamiltonians, one for each type of C---H bond present, consisting of local mode basis functions subject to coupling with symmetrically equivalent bonds and to Fermi resonances with suitable low frequency vibrations. Best-fit model parameters were determined using least-squares routines and the model predictions are compared to the observed band positions and intensities. Some discussion is given of the relevance of the observed couplings to intramolecular vibrational redistribution (IVR) which results in the observation of statistical behaviour in cyclobutene isomerization induced by excitation of C---H stretching overtones in the visible region.

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The coordination chemistry of iso-butyramide based ligands such as: (C3H7CON)-C-i((C3H7)-C-i)(2), (C3H7CON)-C-i(C4H9)(2) and (C3H7CON)-C-i((C4H9)-C-i)(2) with [UO2(NO3)(2) center dot 6H(2)O], [UO2(OO)(2) center dot 2H(2)O] {where OO = C4H3SCOCHCCCF3 (TTA), C6H5COCHCOCF3 (BTA) and C6H5COCHCOC6H5 (DBM)), [Th(NO3)(4) center dot 6H(2)O] and [La(NO3)(3) center dot 6H(2)O] has been evaluated. Structures for the compounds [UO2(NO3)(2)CC3H7CON{(C4H9)-C-i}(2))(2)] and [UO2(C6H5COCHCOC6H5)(2)((C3H7CON)-C-i{(C3H7)-C-i)(2))] have been determined by single crystal X-ray diffraction methods. Preliminary separation studies from nitric acid medium using the amide (C3H7CON)-C-i((C4H9)-C-i)(2) with U(VI), Th(IV) and La(Ill) ions showed the selective precipitation of uranyl ion from the mixture. Thermal study of the compound [UO2(NO3)(2)((C3H7CON)-C-i((C4H9)-C-i)(2))(2)] in air revealed that the ligands can be destroyed completely on incineration. (C) 2008 Elsevier Ltd. All rights reserved.

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Species of the genus Culex Linnaeus have been incriminated as the main vectors of lymphatic filariases and are important vectors of arboviruses, including West Nile virus. Sequences corresponding to a fragment of 478 bp of the cytochrome c oxidase subunit I gene, which includes part of the barcode region, of 37 individuals of 17 species of genus Culex were generated to establish relationships among five subgenera, Culex, Phenacomyia, Melanoconion, Microculex, and Carrollia, and one species of the genus Lutzia that occurs in Brazil. Bayesian methods were employed for the phylogenetic analyses. Results of sequence comparisons showed that individuals identified as Culex dolosus, Culex mollis, and Culex imitator possess high intraspecific divergence (3.1, 2.3, and 3.5%, respectively) when using the Kimura two parameters model. These differences were associated either with distinct morphological characteristics of the male genitalia or larval and pupal stages, suggesting that these may represent species complexes. The Bayesian topology suggested that the genus and subgenus Culex are paraphyletic relative to Lutzia and Phenacomyia, respectively. The cytochrome c oxidase subunit I sequences may be a useful tool to both estimate phylogenetic relationships and identify morphologically similar species of the genus Culex.

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We show that a 2-homogeneous polynomial on the complex Banach space c(0)(l(2)(i)) is norm attaining if and only if it is finite (i.e, depends only on finite coordinates). As the consequence, we show that there exists a unique norm-preserving extension for norm-attaining 2-homogeneous polynomials on c(0)(l(2)(i)).

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Jag har jämfört hur unga människor lyssnade på inspelad musik på 1970-talet med hur unga lyssnar idag. Jag har gjort en enkätundersökning där två grupper, en som är ung idag och en som var ung på 1970-talet, fått svara på frågor om sitt musiklyssnande. Enkäten har jag kompletterat med fyra intervjuer. Den stora skillnaden när det gäller förutsättningarna för lyssnandet, är övergången från analog till digital teknik. Idag lyssnar vi mer vid datorn eller i portabla medier som mp3-spelare eller mobiltelefoner. På 1970-talet var man mer bunden till stationära anläggningar som stereoanläggningen eller radion. Teknikskiftet har också påverkat hur man lyssnar. Förr lyssnade man oftare tillsammans. Idag har det fysiska lyssnandet individualiserats. Den sociala interaktionen har i hög grad flyttat ut i cyberrymden: Man byter spotifylistor, man tipsar om klipp på youtube, man delar med sig av sin egenproducerade musik på myspace osv. Lars Lilliestam använder begreppet musikantropologi för att beskriva studiet av musik som en social aktivitet. Möjligheten att välja ur ett enormt utbud och sätta ihop sina egna spellistor har gett lyssnaren större kontroll över sitt lyssnande. De portabla medierna innebär också en möjlighet till effektivt tidsutnyttjande; man tar med sig musiken samtidigt som man gör något annat. Marie Strand Skånland har undersökt hur mp3-spelare används i vardagen och kommit fram till att musik används som en resurs. Lyssnande på personligt utvald musik, i form av spellistor, kan ge en känsla av kontroll över sig själv, omgivningen och över andra. Man stänger in sig i sin egen ljudbubbla.Lyssnarna anser att ljudkvaliteten har stor betydelse för musikupplevelsen. Men åsikterna går isär, både om vad som är bra ljudkvalitet och om vad som är en bra musikupplevelse.

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Under många år har ”invandringsfrågan” varit en mycket debatterad fråga. Detta märks inte minst i alla de insändare som publicerats i Dalarnas morgontidningar. Integration och ekonomi är exempel på ämnen som nämns i dessa insändare då diskursen invandring diskuteras. En betydande faktor i debatten har bland annat varit Sverigedemokraternas valframgångar. Med denna undersökning vill vi försöka kartlägga hur diskursen invandring framställs i insändare från Dala-demokraten. Detta har gjorts med en innehålls- och diskursanalys. Analysen har utgått från insändare mellan tidsperioden augusti-april 2002/2003 och 2014/2015, vilket motsvarar tiden kring de båda riksdagsvalen.Analysen har genererat fyra teman (mångkultur och svenskhet, integrationsfrågan och invandring, demokrati och yttrandefrihet och ekonomi och välfärd) som diskursen invandring kretsar kring. Utifrån dessa teman har vår analys visat att Sverigedemokraternas valframgångar tenderar att delvis influera diskursen invandring som insändarskribenterna förmedlar. Diskursen invandring har gått från att kretsa kring integrationsproblematik 2002/2003 till ekonomisk problematik 2014/2015. Analysen har även visat på ett ”vi och dem”-tänk som genomsyrar diskursen invandring under bägge tidsperioder. Detta sker både genom fördomsfulla framställningar av andra människor och i uppdelningen av vilka som ”bör” få ta del av Sveriges gemensamma medel.

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Angiotensin (Ang) I-converting enzyme (ACE) is a Zn2+ metalloprotease with two homologous catalytic domains. Both the N- and C-terminal domains are peptidyl dipeptidases. Hydrolysis by ACE of its decapeptide substrate Ang I is increased by Cl−, but the molecular mechanism of this regulation is unclear. A search for single substitutions to Gln among all conserved basic residues (Lys/Arg) in human ACE C-domain identified R1098Q as the sole mutant that lacked Cl− dependence. Cl−dependence is also lost when the equivalent Arg in the N-domain, Arg500, is substituted with Gln. The Arg1098 to Lys substitution reduced Cl− binding affinity by ∼100-fold. In the absence of Cl−, substrate binding affinity (1/K m) of and catalytic efficiency (k cat/K m) for Ang I hydrolysis are increased 6.9- and 32-fold, respectively, by the Arg1098 to Gln substitution, and are similar (<2-fold difference) to the respective wild-type C-domain catalytic constants in the presence of optimal [Cl−]. The Arg1098 to Gln substitution also eliminates Cl− dependence for hydrolysis of tetrapeptide substrates, but activity toward these substrates is similar to that of the wild-type C-domain in the absence of Cl−. These findings indicate that: 1) Arg1098 is a critical residue of the C-domain Cl−-binding site and 2) a basic side chain is necessary for Cl− dependence. For tetrapeptide substrates, the inability of R1098Q to recreate the high affinity state generated by the Cl−-C-domain interaction suggests that substrate interactions with the enzyme-bound Cl− are much more important for the hydrolysis of short substrates than for Ang I. Since Cl− concentrations are saturating under physiological conditions and Arg1098 is not critical for Ang I hydrolysis, we speculate that the evolutionary pressure for the maintenance of the Cl−-binding site is its ability to allow cleavage of short cognate peptide substrates at high catalytic efficiencies.

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Three new ortho -metallated palladium complexes, [Pd(O,O’-hfacac)(κ2-2-C6F4PPh2)] (11), [Pd2(O,O’hfacac)2(μ-2-C6F4PPh2)2](12) and [Pd(O,O’-hfacac)(κC-2-C6F4PPh2)(PPh3)] (13) (hfacac = hexafluoroace-tylacetonate), have been prepared and fully characterised. The electrochemical reductions of complexes 11–13, together with those of other cyclopalladated complexes containing 2C6R4PPh2 ligands (R = H, F) were studied by cyclic, rotating disk and microelectrode voltammetry. Evidence for the one-electron reduction of [PdI(κ2-2-C6F4PPh2)(PPh2Fc)] (6) was obtained from coulometric analysis, although the product is unstable and undergoes further chemical processes. Preparative electro-reduction of [Pd2(μ-Br)2(κ2-2-C6F4PPh2)2] (7) in CH2Cl2 causes reductive cleavage of its Pd–C σ-bonds and formation of the complex [PdBr2{PPh2(2-C6F4H)}2](14); possible mechanisms are discussed.

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O objetivo desta monografia é verificar se a receita municipal, em especial o ICM transferido dos Estados está relacionada com a estrutura produtiva. Em outras palavras, pretende-se investigar se a atual sistemática de distribuição do ICM privilegia os municípios de maior estrutura produtiva, resultando, portanto, em desequilíbrios financeiros entre municípios de uma mesma região. A partir das conclusões extraídas, pretende-se estabelecer formulações e indicações que contribuam para o debate de alternativas tributárias.

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No âmbito da dissertação apresentada à Universidade da Madeira para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Engenharia Civil, foi desenvolvida uma pesquisa na área da Segurança Contra Incêndio em Edifícios, abreviadamente designada por SCIE, desde 1951 a 2008 e a sua aplicação como especialidade da Engenharia, designadamente ao nível da fenomenologia da combustão, no que concerne à evolução histórica dos organismos, legislação, normas técnicas e factos históricos marcantes ao nível socioeconómico. Foi feita uma abordagem às normas europeias e à sua transcrição para as normas portuguesas devido ao factor político com a entrada de Portugal na C.E.E. em 1986. Neste sentido, este trabalho pretende dar a conhecer a evolução da SCIE em Portugal e exemplifica a sua aplicação como especialidade obrigatória para o licenciamento de qualquer edifício, independentemente da sua Utilização-Tipo à excepção dos estabelecimentos prisionais, instalações das forças armadas, espaços destinados ao armazenamento de explosivos e pirotecnia. O estudo de caso escolhido foi de um edifício de utilização mista da 4ª Categoria de Risco. Identificaram-se as diferenças entre a legislação anterior e o novo Diploma, a evolução histórica e as medidas a implementar no estudo de caso, apresentado no (anexo II), de acordo com o novo quadro legislativo.

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During the winding process of HTS coils the tapes of Bi-2223 are subjected to the influence of bending strain, axial strain, compressive force and torsional deformation resulting in I-c degradation. In the literature the effects of the individual strain components are separately analyzed in spite of during coil winding and energizing the strain-stress effects are combined. In this work using commercial tapes of Bi-2223 Ag/AgMg with and without stainless steel reinforcement several samples were wound on cylindrical FRP G-10 holder in which different combined strains are applied. Measurements of I - V characteristic curves are done to determine the degree of critical current degradation and the operational limits. The results are compared with the I, values of short samples and other specimens subjected to deformation generated by loading types such as tensile and bending strain.