976 resultados para electronic communication


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This study discusses the importance of establishing trust in post-acquisition integration context and how the use of e-channels facilitates or inhibits this process. The objective of this study is to analyze how the use of electronic communication channels influences the post-acquisition integration process in terms of trust establishment and overall integration efficiency, developing a framework as a result. Three sub-objectives are introduced: to find out the building blocks of trust in M&A’s, to analyse how the use of e-channels influence the process of trust establishment in post-acquisition integration context, and to define the consequences trust and use of e-channels have for the process. The theoretical background of the study includes literature and theories relating to trust establishment in post-acquisition integration context and how the use of e-channels influences the process of trust development on a general level. The empirical research is conducted as a single case study, based on key informant interviews. The interview data was collected between October 2015 and January 2016. Altogether nine interviews were realised; six with representatives from the acquiring firm and three with target firm members. Thematic analysis was selected as the main method for analysing and processing the qualitative data. This study finds that trust has an essential role in post-acquisition integration context, facilitating the integration process in various different ways. Hence, identifying the different building blocks of trust is important in order for members of the organisations to be better able establish and maintain trust. In today’s international business, the role of electronic communication channels has also increased in importance significantly and it was confirmed that these pose both challenges and possibilities for the development of interpersonal trust. One of the most important underlying factors influencing the trust levels via e-communication channels is the level of user’s comfort in using the different e-channels. Without sufficient and meaningful training, the communication conducted via these channels in inhibited in a number of ways. Hence, understanding the defining characteristics of e-communication together with the risks and opportunities related to the use of these can have far-reaching consequences for the post-acquisition integration process as a whole. The framework based on the findings and existing theory introduces the most central factors influencing the trust establishment together with the positive and negative consequences these have for the integration process. Moreover, organizational level consistency and the existence of shared guidelines on appropriate selection of communication channels according to the nature of the task at hand are seen as important

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Porphyrins are one of Nature’s essential building blocks that play an important role in several biological systems including oxygen transport, photosynthesis, and enzymes. Their capacity to absorb visible light, facilitate oxidation and reduction, and act as energy- and electron-transfer agents, in particular when several are held closely together, is of interest to chemists who seek to mimic Nature and to make and use these compounds in order to synthesise novel advanced materials. During this project 26 new 5,10-diarylsubstituted porphyrin monomers, 10 dimers, and 1 tetramer were synthesised. The spectroscopic and structural properties of these compounds were investigated using 1D/2D 1H NMR, UV/visible, ATR-IR and Raman spectroscopy, mass spectrometry, X-ray crystallography, electrochemistry and gel permeation chromatography. Nitration, amination, bromination and alkynylation of only one as well as both of the meso positions of the porphyrin monomers have resulted in the expansion of the synthetic possibilities for the 5,10-diarylsubstituted porphyrins. The development of these new porphyrin monomers has led to the successful synthesis of new azo- and butadiyne-linked dimers. The functionalisation of these compounds was investigated, in particular nitration, amination, and bromination. The synthesised dimers containing the azo bridge have absorption spectra that show a large split in the Soret bands and intense Q-bands that have been significantly redshifted. The butadiyne dimers also have intense, red-shifted Q-bands but smaller Soret band splittings. Crystal structures of two new azoporphyrins have been acquired and compared to the azoporphyrin previously synthesised from 5,10,15- triarylsubstituted porphyrin monomers. A completely new cyclic porphyrin oligomer (CPO) was synthesised comprising four porphyrin monomers linked by azo and butadiyne bridges. This is the first cyclic tetramer that has both the azo and butadiyne linking groups. The absorption spectrum of the tetramer exhibits a large Soret split making it more similar to the azo- dimers than the butadiyne-linked dimers. The spectroscopic characteristics of the synthesised tetramer have been compared to the characteristics of other cyclic porphyrin tetramers. The collected data indicate that the new synthesised cyclic tetramer has a more efficient ð-overlap and a better ground state electronic communication between the porphyrin rings.

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Increasingly, almost everything we do in our daily lives is being influenced by information and communications technologies (ICTs) including the Internet. The task of governance is no exception with an increasing number of national, state, and local governments utilizing ICTs to support government operations, engage citizens, and provide government services. As with other things, the process of governance is now being prefixed with an “e”. E-governance can range from simple Web sites that convey basic information to complex sites that transform the customary ways of delivering all sorts of government services. In this respect local e-government is the form of e-governance that specifically focuses on the online delivery of suitable local services by local authorities. In practice local e-government reflects four dimensions, each one dealing with the functions of government itself. The four are: (a) e-services, the electronic delivery of government information, programs, and services often over the Internet; (b) e-management, the use of information technology to improve the management of government. This might range from streamlining business processes to improving the flow of information within government departments; (c) e-democracy the use of electronic communication vehicles, such as e-mail and the Internet, to increase citizen participation in the public decision-making process; (d) e-commerce, the exchange of money for goods and services over the Internet which might include citizens paying taxes and utility bills, renewing vehicle registrations, and paying for recreation programs, or government buying office supplies and auctioning surplus equipment (Cook, LaVigne, Pagano, Dawes, & Pardo, 2002). Commensurate with the rapid increase in the process of developing e-governance tools, there has been an increased interest in benchmarking the process of local e-governance. This benchmarking, which includes the processes involved in e-governance as well as the extent of e-governance adoption or take-up is important as it allows for improved processes and enables government agencies to move towards world best practice. It is within this context that this article discusses benchmarking local e-government. It brings together a number of discussions regarding the significance of benchmarking, best practices and actions for local e-government, and key elements of a successful local e-government project.

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The syntheses, properties and electronic structures of a series of porphyrin dimers connected by two-atom bridges were compared. The study found that an azo linker results in the most efficient electronic communication between the two porphyrin rings, and is the superior connector for dimers, trimers and oligomers in the design of nonlinear optical materials. This has implications for the design of molecular probes and sensors, photodynamic therapy, microfabrication, and three-dimensional optical data storage. The research led to the synthesis of a number of new porphyrin monomers and dimers, which were characterised using structural, spectroscopic and spectrometric techniques.

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This paper describes the electrocatalytic oxidation of ascorbic acid (AA) in phosphate buffer solution by the immobilized citrate capped gold nanoparticles (AuNPs) on 1,6-hexanedithiol (HDT) modified Au electrode. X-ray photoelectron spectrum (XPS) of HDT suggests that it forms a monolayer on Au surface through one of the two single bondSH groups and the other single bondSH group is pointing away from the electrode surface. The free single bondSH groups of HDT were used to covalently attach colloidal AuNPs. The covalent attachment of AuNPs on HDT monolayer was confirmed from the observed characteristic carboxylate ion stretching modes of citrate attached with AuNPs in the infra-red reflection absorption spectrum (IRRAS) in addition to a higher reductive desorption charges obtained for AuNPs immobilized on HDT modified Au (Au/HDT/AuNPs) electrode in 0.1 M KOH when compared to HDT modified Au (Au/HDT) electrode. The electron transfer reaction of [Fe(CN)6]4−/3− was markedly hindered at the HDT modified Au (Au/HDT) electrode while it was restored with a peak separation of 74 mV after the immobilization of AuNPs on Au/HDT (Au/HDT/AuNPs) electrode indicating a good electronic communication between the immobilized AuNPs and the underlying bulk Au electrode through a HDT monolayer. The Cottrell slope obtained from the potential-step chronoamperometric measurements for the reduction of ferricyanide at Au/HDT/AuNPs was higher than that of bare Au electrode indicating the increased effective surface area of AuNPs modified electrode. The Au/HDT/AuNPs electrode exhibits excellent electrocatalytic activity towards the oxidation of ascorbic acid (AA) by enhancing the oxidation peak current to more than two times with a 210 mV negative shift in the oxidation potential when compared to a bare Au electrode. The standard heterogeneous electron transfer rate constant (ks) calculated for AA oxidation at Au/HDT/AuNPs electrode was 5.4 × 10−3 cm s−1. The oxidation peak of AA at Au/HDT/AuNPs electrode was highly stable upon repeated potential cycling. Linear calibration plot was obtained for AA over the concentration range of 1–110 μM with a correlation coefficient of 0.9950. The detection limit of AA was found to be 1 μM. The common physiological interferents such as glucose, oxalate ions and urea do not show any interference within the detection limit of AA. The selectivity of the AuNPs modified electrode was illustrated by the determination of AA in the presence of uric acid.

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Facile synthesis of triad 3 and tetrad 4 incorporating -B(Mes)(2) (Mes = mesityl (2,4,6-trimethylphenyl)), boron dipyrromethene (BODIPY), and triphenylamine is reported. Introduction of two dissimilar acceptors (triarylborane and BODIPY) on a single donor resulted in two distinct intramolecular charge transfer processes (amine-to-borane and amine-to-BODIPY). The absorption and emission properties of the new triad and tetrad are highly dependent on individual building units. The nature of electronic communication among the individual fluorophore units has been comprehensively investigated and compared with building units. Compounds 3 and 4 showed chromogenic and fluorogenic responses for small anions such as fluoride and cyanide.

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A new triarylborane-aza-BODIPY conjugate is reported. The compound consists of two blue emissive dimesitylarylborane moieties and a near-infrared (NIR) emissive aza-BOIDPY core and shows panchromatic absorption spanning approximately 300-800 nm. DFT computational studies suggest limited electronic communication between the individual fluorophore units. Hence, the partial energy transfer from blue fluorophore triarylborane to NIR chromophore aza-BODIPY unit leads to a broad dual-emissive feature covering a large part of visible and NIR region. Furthermore, the broadband emissive compound can act as a selective sensor for fluoride anion as a result of fluorescence quenching response in both visible and NIR spectral regions.

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WG 10 Fukuoka Workshop Pacific salmon:climate-linked long-term stock fluctuations The state of the eastern North Pacific in the second half of 1996 The state of the western North Pacific in the second half of 1996 The status of the Bering Sea in the second half of 1996 Yutaka Nagata Eulogy A brief look at mechanisms for support of oceanographic research in the United States Research interests and the funding system for the new Ministry of Maritime Affairs and Fisheries of the Republic of Korea PICES and electronic communication Japan Meteorological Agency: oceanographic activities

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The cytochromes P450 (P450s) are a remarkable class of heme enzymes that catalyze the metabolism of xenobiotics and the biosynthesis of signaling molecules. Controlled electron flow into the thiolate-ligated heme active site allows P450s to activate molecular oxygen and hydroxylate aliphatic C–H bonds via the formation of high-valent metal-oxo intermediates (compounds I and II). Due to the reactive nature and short lifetimes of these intermediates, many of the fundamental steps in catalysis have not been observed directly. The Gray group and others have developed photochemical methods, known as “flash-quench,” for triggering electron transfer (ET) and generating redox intermediates in proteins in the absence of native ET partners. Photo-triggering affords a high degree of temporal precision for the gating of an ET event; the initial ET and subsequent reactions can be monitored on the nanosecond-to-second timescale using transient absorption (TA) spectroscopies. Chapter 1 catalogues critical aspects of P450 structure and mechanism, including the native pathway for formation of compound I, and outlines the development of photochemical processes that can be used to artificially trigger ET in proteins. Chapters 2 and 3 describe the development of these photochemical methods to establish electronic communication between a photosensitizer and the buried P450 heme. Chapter 2 describes the design and characterization of a Ru-P450-BM3 conjugate containing a ruthenium photosensitizer covalently tethered to the P450 surface, and nanosecond-to-second kinetics of the photo-triggered ET event are presented. By analyzing data at multiple wavelengths, we have identified the formation of multiple ET intermediates, including the catalytically relevant compound II; this intermediate is generated by oxidation of a bound water molecule in the ferric resting state enzyme. The work in Chapter 3 probes the role of a tryptophan residue situated between the photosensitizer and heme in the aforementioned Ru-P450 BM3 conjugate. Replacement of this tryptophan with histidine does not perturb the P450 structure, yet it completely eliminates the ET reactivity described in Chapter 2. The presence of an analogous tryptophan in Ru-P450 CYP119 conjugates also is necessary for observing oxidative ET, but the yield of heme oxidation is lower. Chapter 4 offers a basic description of the theoretical underpinnings required to analyze ET. Single-step ET theory is first presented, followed by extensions to multistep ET: electron “hopping.” The generation of “hopping maps” and use of a hopping map program to analyze the rate advantage of hopping over single-step ET is described, beginning with an established rhenium-tryptophan-azurin hopping system. This ET analysis is then applied to the Ru-tryptophan-P450 systems described in Chapter 2; this strongly supports the presence of hopping in Ru-P450 conjugates. Chapter 5 explores the implementation of flash-quench and other phototriggered methods to examine the native reductive ET and gas binding events that activate molecular oxygen. In particular, TA kinetics that demonstrate heme reduction on the microsecond timescale for four Ru-P450 conjugates are presented. In addition, we implement laser flash-photolysis of P450 ferrous–CO to study the rates of CO rebinding in the thermophilic P450 CYP119 at variable temperature. Chapter 6 describes the development and implementation of air-sensitive potentiometric redox titrations to determine the solution reduction potentials of a series of P450 BM3 mutants, which were designed for non-native cyclopropanation of styrene in vivo. An important conclusion from this work is that substitution of the axial cysteine for serine shifts the wild type reduction potential positive by 130 mV, facilitating reduction by biological redox cofactors in the presence of poorly-bound substrates. While this mutation abolishes oxygenation activity, these mutants are capable of catalyzing the cyclopropanation of styrene, even within the confines of an E. coli cell. Four appendices are also provided, including photochemical heme oxidation in ruthenium-modified nitric oxide synthase (Appendix A), general protocols (Appendix B), Chapter-specific notes (Appendix C) and Matlab scripts used for data analysis (Appendix D).

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Objetivo. Avaliar o impacto de ações para promoção do consumo de frutas e hortaliças (FH) no ambiente de trabalho. Método. Estudo de intervenção tipo antes e depois não randomizado com grupo controle histórico, realizado em empresa do ramo da pesquisa científica. A população de estudo consistiu em funcionários que almoçaram no restaurante da empresa nos dias do estudo. No diagnóstico inicial, foram coletados dados de caracterização da empresa estudada e da empresa fornecedora de refeições, caracterização sociodemográfica e consumo de FH pelos indivíduos estudados e sua opinião sobre temas ligados a FH. Foi também realizado grupo focal com formadores de opinião da empresa, a fim de conhecer os determinantes do seu consumo de FH com vistas a subsidiar a construção de estratégias para sua promoção. A intervenção durou oito meses, sendo composta por duas vertentes: ambiental (refeitório da empresa) e educativa (dirigida aos indivíduos). Na primeira, investiu-se na sensibilização do proprietário da empresa concessionária e da responsável técnica para a importância da promoção de FH e em contatos regulares com ela a fim subsidiá-la para a oferta de FH no refeitório. Na segunda, foram realizadas atividades presenciais, distribuídos materiais educativos e desenvolvidas ações de comunicação eletrônica. No diagnóstico final, além do consumo de FH pelos funcionários, foram registrados o nível de exposição dos funcionários à intervenção e suas impressões sobre modificações no restaurante da empresa no tocante à oferta de FH. A análise do impacto da intervenção consistiu no exame da relevância da diferença observada entre proporções ou médias obtidas antes e depois da intervenção. A associação entre intervenção e desfechos foi examinada por meio de modelos de regressão múltipla controlando-se para a situação de consumo inicial e para fatores sociodemográficos dos indivíduos. Resultados. Foram estudados 61 indivíduos. A média de cobertura das atividades e materiais educativos foi de 63,5%, sendo esses avaliados positivamente por 98% dos funcionários. Cerca de 2/3 dos funcionários perceberam mudanças em pelo menos dois aspectos referentes a variedade e aparência das preparações. Do total, 88,6% confiavam na higiene desses alimentos no momento pós intervenção contra 56,9% no momento pré intervenção. Houve um aumento de 53,6g (38%) no consumo de FH no almoço realizado no ambiente de trabalho. Houve também aumento no consumo regular de verduras (de 47,5 para 72,1%), e no número médio de dias de consumo de verduras (de 4,4 para 5,6 dias). Foi observada associação entre aumento do consumo de FH e mudança positiva na confiança em relação à higiene dos alimentos oferecidos crus; aumento do consumo de hortaliças e mudança positiva na confiança em relação à higiene dos alimentos oferecidos crus e nível de exposição à vertente educativa da intervenção; e aumento na média de dias de consumo de legumes e percepção de mudanças positivas na variedade e na apresentação das preparações com FH. Conclusão. Houve um aumento no consumo de FH entre funcionários expostos à intervenção. Seu desenho multicomponente parece ter contribuído para os achados do estudo.

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A presente dissertação contempla estudos de funcionalização de 5,10,15,20- tetrafenilporfirina via grupos nitro e amino e a preparação de sistemas porfirina-ftalocianina. Este trabalho encontra-se dividido em quatro partes. Na primeira parte descrevem-se as características gerais de porfirinas e ftalocianinas bem como algumas metodologias de síntese utilizadas na sua preparação e suas potenciais aplicações. Na segunda parte desta dissertação descreve-se a funcionalização de 5,10,15,20-tetrafenilporfirina com arilaminas recorrendo a duas rotas sintéticas diferentes. A reacção de 2-nitro-5,10,15,20-tetrafenilporfirina com anilina ou aminas aromáticas substituídas com grupos dadores de electrões permitiu, através do ataque do nucleófilo ao carbono beta-pirrólico onde está ligado o grupo nitro, ataque ipso, a obtenção de derivados do tipo 2-arilaminoporfirinas e derivados porfirínicos de anéis fundidos, sendo estes últimos resultantes da ciclização oxidativa de 2-arilaminoporfirinas. A reacção entre (2-amino- 5,10,15,20-tetrafenilporfirinato)níquel(II) e brometos de arilo na presença de paládio, reacção de aminação de Buchwald-Hartwig, permitiu, após descomplexação, a preparação de novos derivados do tipo 2- arilaminoporfirinas com grupos substituintes dadores e aceitadores de electrões. Um dos derivados porfirínicos de anéis fundidos foi submetido a reacção de complexação com diferentes iões metálicos e foram estudadas as respectivas propriedades fotoquímicas e electroquímicas. Esses estudos revelaram que estes compostos são bons geradores de oxigénio singuleto e que sofrem processos de oxidação-redução electroquimicamente reversíveis. Esta metodologia foi estendida ainda a brometos de hetarilo (derivados de piridina e tiofeno). Recorrendo ao acoplamento, em condições de Buchwald-Hartwig, de complexos metálicos da 5,10,15,20-tetrafenilporfirina, funcionalizados com grupos amino e bromo, preparam-se dímeros porfirina-amino-porfirina, cujos espectros electrónicos revelam a existência de uma boa “comunicação electrónica” entre as duas subunidades. A terceira parte descreve a síntese de sistemas porfirina-ftalocianina. Recorrendo à condensação estatística entre a 5,10,15,20-tetrafenilporfirina substituída com um grupo ftalonitrilo na posição beta-pirrólica com ftalonitrilo ou ftalonitrilo substituído foram obtidas díades porfirina-ftalocianina onde as duas subunidades se encontram directamente ligadas ou fundidas. Os porfirinilftalonitrilos necessários para a síntese das diferentes díades foram preparados através da reacção de adição do fumaronitrilo à 5,10,15,20- tetrafenilporfirina funcionalizada com o grupo 1,3-butadienilo ou vinilo, seguida de oxidação do aducto resultante. O acoplamento catalisado por paládio entre (2-bromo-5,10,15,20- tetrafenilporfirinato)zinco(II) e [9(10),16(17),23(24)-tri-terc-butil-2- etinilftalocianinato]zinco(II) permitiu a síntese de uma díade porfirinaftalocianina com as duas unidades ligadas por um grupo etinilo. Uma pentíade porfirina-ftalocianina foi obtida através da ciclotetramerização de um dos porfirinilftalonitrilos. A comparação dos espectros electrónicos das diferentes classes de sistemas revela que as correspondentes propriedades electrónicas são altamente afectadas pela distância entre as subunidades e também pelo número de cromóforos presentes no sistema. Os estudos fotofísicos de alguns dos novos compostos acima referidos permitiram verificar a ocorrência eficiente de transferência de energia da subunidade porfirínica para a da ftalocianina, capacidade essa que permitirá a estes sistemas serem usados para modelar o processo fotossintético. Na última parte descrevem-se, pormenorizadamente, todas as experiências efectuadas e as caracterizações espectroscópicas, nomeadamente de espectroscopia de ressonância magnética nuclear (RMN), espectrometria de massa e espectrofotometria de UV-vis, dos compostos sintetizados. Nalguns casos recorreu-se ainda a técnicas de RMN bidimensionais como COSY, HSQC, HMBC, NOESY e ROESY.

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A difusão das tecnologias da informação e comunicação fomenta mudanças qualitativas nas práticas pedagógicas, proporcionando a criação de comunidades de aprendizagem entre aprendentes de diferentes pontos do mundo. Tendo como referência a pedagogia crítica para a emancipação (Freire, 1997; Giroux, 1997), este estudo analisou de que forma aprendentes de diferentes proveniências linguístico-culturais desenvolvem a sua consciência cultural crítica (Byram, 1997), quando colocados em situação de trabalho colaborativo on-line, formando uma comunidade de aprendizagem, através do recurso a uma plataforma especialmente concebida para o efeito, a 2ndschool.eu, na qual foram levados a desenvolver um trabalho de natureza interdisciplinar. Pretendíamos que esta plataforma fomentasse questionamentos por parte dos seus membros. Como tal, integrámos diferentes instrumentos de comunicação eletrónica (chat, fóruns e e-mail), através dos quais se promoveu a interação entre os participantes no projeto, alunos e professores (de diversas áreas disciplinares) do Ensino Secundário belga, búlgaro, grego, polaco, português e sueco, com vista à realização de uma tarefa comum: a edição de um trabalho de projeto de análise crítica de reportagens, artigos de opinião e fotos de jornais acerca de tópicos da atualidade nacional e/ou internacional. Tivemos em conta uma metodologia de investigação mais orientada para o estudo de caso e análise do discurso. Para tal, recorremos a dois tipos de instrumentos de recolha de dados: as impressões das discussões estabelecidas através de chat, fóruns, blogs e wikis e os resultados de três questionários sobre o perfil sociolinguístico e cultural dos participantes, a avaliação da plataforma virtual e o inventário de estratégias mais eficazes na negociação de saberes estabelecida. Concluímos que os alunos (re)constroem saberes, pois revelam representações que têm acerca de situações-problema, refletem acerca das mesmas e, posteriormente, disseminam ativamente pontos de vista críticos através de ferramentas Web 2.0, como forma de as resolver. Enquanto verdadeiros pronetários, foram capazes de recorrer a estratégias de comunicação que fomentam a busca de entendimento com o Outro, num caminho oscilante entre o concordar e o discordar, entre o ajudar e o solicitar ajuda, entre o opinar e o escutar, entre o avaliar e o ser avaliado e entre o corrigir e o ser corrigido. Identificámos como principais limitações do nosso estudo a dificuldade de análise das práticas interdisciplinares dos interlocutores internacionais, a desmotivação de alguns aprendentes nas tarefas e ainda o reduzido recurso ao videochat, pelo desconforto no seu uso. Por isso, consideramos que futuras investigações deverão debruçar-se nestas questões.

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[CoCl(-Cl)(Hpz(Ph))(3)](2) (1) and [CoCl2(Hpz(Ph))(4)] (2) were obtained by reaction of CoCl2 with HC(pz(Ph))(3) and Hpz(Ph), respectively (Hpz(Ph)=3-phenylpyrazole). The compounds were isolated as air-stable solids and fully characterized by IR and far-IR spectroscopy, MS(ESI+/-), elemental analysis, cyclic voltammetry (CV), controlled potential electrolysis, and single-crystal X-ray diffraction. Electrochemical studies showed that 1 and 2 undergo single-electron irreversible (CoCoIII)-Co-II oxidations and (CoCoI)-Co-II reductions at potentials measured by CV, which also allowed, in the case of dinuclear complex 1, the detection of electronic communication between the Co centers through the chloride bridging ligands. The electrochemical behavior of models of 1 and 2 were also investigated by density functional theory (DFT) methods, which indicated that the vertical oxidation of 1 and 2 (that before structural relaxation) affects mostly the chloride and pyrazolyl ligands, whereas adiabatic oxidation (that after the geometry relaxation) and reduction are mostly metal centered. Compounds 1 and 2 and, for comparative purposes, other related scorpionate and pyrazole cobalt complexes, exhibit catalytic activity for the peroxidative oxidation of cyclohexane to cyclohexanol and cyclohexanone under mild conditions (room temperature, aqueous H2O2). Insitu X-ray absorption spectroscopy studies indicated that the species derived from complexes 1 and 2 during the oxidation of cyclohexane (i.e., Ox-1 and Ox-2, respectively) are analogous and contain a Co-III site. Complex 2 showed low invitro cytotoxicity toward the HCT116 colorectal carcinoma and MCF7 breast adenocarcinoma cell lines.

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The scope of the present work is to study the legal protection conferred upon the consumer in Angola, especially as regards electronic communication agreements. Its purpose is to promote consumers’ rights and contribute to its defence given the relatively privileged position of professionals in their relationship with consumers. With this in mind, we have made a description of the Consumer Law in Angola based on the Angolan Constitution (as the law that establishes the fundamental rights and guarantees of citizens) and on the Consumer’s Defence Law, which, as the basic law regarding consumers’ rights, provides the framework for this dissertation. We have analysed several aspects relating to consumer relationships, starting from its concept and rights of consumers and covering the legal and contractual mechanisms put in place for their protection. We have also analysed the Advertising Law with a view to better understand consumer’s rights before advertising campaigns carried out by professionals whilst promoting their goods and services and, additionally, to understand the duties and principles that shall be complied with in such campaigns with the purpose to protect the rights and interests of consumers. From a criminal point of view, we have briefly covered the crimes against consumers provided for in the Penal Code and the Law of Infractions against the Economy. In the second part of this work, we have summarised the institutions that protect the rights and interests of consumers, which include the Public Prosecutor Office, the National Institute for the Defence of the Consumers and the Consumers’ Associations. The third and last part of this work covers electronic communications agreements. Given the fact that there is no specific legislation in this matter, our analysis was based on the Civil Code – specifically the part relating to contracts – the Law on General Contractual Terms and Conditions and the Consumer’s Defence Law. We have analysed the formation of contracts, compliance and consumers’ rights resulting from contract breach. We further have appealed to the Angolan legislator to legislate certain aspects of consumer relationships, especially those where breach of consumers’ rights are blatant and facilitated by the lack of specific laws addressing such cases.

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Optical absorption studies of phthalocyanines (Pc-s) in borate glass matrix have been reported for the first time. Measurements have been done corresponding to photon energies between 1.1 and 6.2 eV for free base, manganese, iron, nickel, molybdenum, cobalt and copper phthalocyanines. Several new discrete transitions are observed in the UV–vis region of the spectra in addition to a strong continuum component of absorption in the IR region. Values of some of the important optical constants viz. absorption coefficient (α), molar extinction coefficient (ε), absorption cross-section (σa), band width (Δλ), electric dipole strength (q2) and oscillator strength (f) for the relevant electronic transitions are also presented. All the data reported for Pc-s in the new matrix have been compared with those corresponding to solution, vapor and thin film media.