805 resultados para Theoretical Considerations


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Baths containing sulphuric acid as catalyst and others with selected secondary catalysts (methane sulphonic acid - MSA, SeO2, a KBrO3/KIO3 mixture, indium, uranium and commercial high speed catalysts (HEEF-25 and HEEF-405)) were studied. The secondary catalysts influenced CCE, brightness and cracking. Chromium deposition mechanisms were studied in Part II using potentiostatic and potentiodynamic electroanalytical techniques under stationary and hydrodynamic conditions. Sulphuric acid as a primary catalyst and MSA, HEEF-25, HEEF-405 and sulphosalycilic acid as co-catalysts were explored for different rotation, speeds and scan rates. Maximum current was resolved into diffusion and kinetically limited components, and a contribution towards understanding the electrochemical mechanism is proposed. Reaction kinetics were further studied for H2SO4, MSA and methane disulphonic acid catalysed systems and their influence on reaction mechanisms elaborated. Charge transfer coefficient and electrochemical reaction rate orders for the first stage of the electrodeposition process were determined. A contribution was made toward understanding of H2SO4 and MSA influence on the evolution rate of hydrogen. Anodic dissolution of chromium in the chromic acid solution was studied with a number of techniques. An electrochemical dissolution mechanism is proposed, based on the results of rotating gold ring disc experiments and scanning electron microscopy. Finally, significant increases in chromium electrodeposition rates under non-stationary conditions (PRC mode) were studied and a deposition mechanisms is elaborated based on experimental data and theoretical considerations.

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This volume presents a comprehensive study of what constitutes Translation Competence, from the various sub-competences to the overall skill. Contributors combine experience as translation scholars with their experience as teachers of translation. The volume is organized into three sections: Defining, Building, and Assessing Translation Competence. The chapters offer insights into the nature of translation competence and its place in the translation training programme in an academic environment and show how theoretical considerations have contributed to defining, building and assessing translation competence, offering practical examples of how this can be achieved. The first section introduces major sub-competences, including linguistic, cultural, textual, subject, research, and transfer competence. The second section presents issues relating to course design, methodology and teaching practice. The third section reflects on criteria for quality assessment.

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This article discusses implications of participant withdrawal for inductive research. I describe and analyze how a third of my participants withdrew from a grounded theory study. I position my example, ensuing issues, and potential solutions as reflective of inductive methodologies as a whole. The crux of the problem is the disruption inflicted by withdrawal on inductive processes of generating knowledge. I examine the subsequent methodological and ethical issues in trying to determine the best course of action following withdrawal. I suggest three potential options for researchers: Continuing the study with partial data, continuing the study with all data, and discontinuing the study. Motivated by my experience, and wider theoretical considerations, I present several suggestions and questions, with the aim of supporting researchers in determining the best course of action for their individual field circumstances.

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We examine how the most prevalent stochastic properties of key financial time series have been affected during the recent financial crises. In particular we focus on changes associated with the remarkable economic events of the last two decades in the volatility dynamics, including the underlying volatility persistence and volatility spillover structure. Using daily data from several key stock market indices, the results of our bivariate GARCH models show the existence of time varying correlations as well as time varying shock and volatility spillovers between the returns of FTSE and DAX, and those of NIKKEI and Hang Seng, which became more prominent during the recent financial crisis. Our theoretical considerations on the time varying model which provides the platform upon which we integrate our multifaceted empirical approaches are also of independent interest. In particular, we provide the general solution for time varying asymmetric GARCH specifications, which is a long standing research topic. This enables us to characterize these models by deriving, first, their multistep ahead predictors, second, the first two time varying unconditional moments, and third, their covariance structure.

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The development of nutrition and health guidelines and policies requires reliable scientific information. Unfortunately, theoretical considerations and empirical evidence indicate that a large percentage of science-based claims rely on studies that fail to replicate. The session "Strategies to Optimize the Impact of Nutrition Surveys and Epidemiological Studies" focused on the elements of design, interpretation, and communication of nutritional surveys and epidemiological studies to enhance and encourage the production of reliable, objective evidence for use in developing dietary guidance for the public. The speakers called for more transparency of research, raw data, consistent data-staging techniques, and improved data analysis. New approaches to collecting data are urgently needed to increase the credibility and utility of findings from nutrition epidemiological studies. Such studies are critical for furthering our knowledge and understanding of the effects of diet on health.

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Purpose - The paper develops a model of employee innovative behavior conceptualizing it as distinct from innovation outputs and as a multi-faceted behavior rather than a simple count of ‘innovative acts’ by employees. It understands individual employee innovative behaviors as a micro-foundation of firm intrapreneurship that is embedded in and influenced by contextual factors such as managerial, organizational and cultural support for innovation. Building from a review of existing employee innovative behavior scales and theoretical considerations we develop and validate the Innovative Behavior Inventory (IBI) and the Innovation Support Inventory (ISI). Design/methodology/approach – Two pilot studies, a third validation study in the Czech Republic and a fourth cross-cultural validation study using population representative samples from Switzerland, Germany, Italy and the Czech Republic (N=2812 employees and 450 entrepreneurs) were conducted. Findings - Both inventories were reliable and showed factorial, criterion, convergent and discriminant validity as well as cross-cultural equivalence. Employee innovative behavior was supported as comprising of idea generation, idea search, idea communication, implementation starting activities, involving others and overcoming obstacles. Managerial support was the most proximal contextual influence on innovative behavior and mediated the effect of organizational support and national culture. Originality/value - The paper advances our understanding of employee innovative behavior as a multi-faceted phenomenon and the contextual factors influencing it. Where past research typically focuses on convenience samples within a particular country, we offer first robust evidence that our model of employee innovative behavior generalizes across cultures and types of samples. Our model and the IBI and ISI inventories enable researchers to build a deeper understanding of the important micro-foundation underpinning intrapreneurial behavior in organizations and allow practitioners to identify their organizations’ strengths and weaknesses related to intrapreneurship.

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The successful operation of the regional development – or cohesion – policy of the European Union has a strategic importance from the point of view of the whole integration process. Strengthening economic, social and territorial cohesion and decreasing disparities between member states and regions are not only one of the main priorities of the integration, but at the same time these are justified expectations of the people living in the member states of the union. The cohesion transfers should be spent on those factors which have the biggest contribution to the improvement of development prospects and competitiveness in the given regions. Theories on regional development have controversial conclusions about the long-term formation of development disparities. However, it has become evident that successful development policies are based on endogenous factors, innovation and well-functioning institutions. After examining theoretical considerations and regional disparities the study analyses the impacts of EU regional policy and evaluates the main elements of the proposed regulatory frameworks for the period 2014-2020.

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In this review, the impacts of climate change on Lepidoptera species and communities are summarized, regarding already registered changes in case of individual species and assemblies, and possible future effects. These include changes in abundance, distribution ranges (altitude above sea level, geographical distribution), phenology (earlier or later flying, number of generations per year). The paper also contains a short description of the observed impacts of single factors and conditions (temperature, atmospheric CO2 concentration, drought, predators and parasitoids, UV-B radiation) affecting the life of moths and butterflies, and recorded monitoring results of changes in the Lepidoptera communities of some observed areas. The review is closed with some theoretical considerations concerning the characteristics of “winner” species and also the features and conditions needed for a successful invasion, conquest of new territories.

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Based on theoretical considerations an explanation for the temperature dependence of the thermal expansion and the bulk modulus is proposed. A new equation state is also derived. Additionally a physical explanation for the latent heat of fusion is presented. These theoretical predictions are tested against experiments on highly symmetrical monatomic structures. ^ The volume is not an independent variable and must be broken down into its fundamental components when the relationships to the pressure and temperature are defined. Using zero pressure and temperature reference frame, the initial parameters, volume at zero pressure and temperature[V°], bulk modulus at zero temperature [K°] and volume coefficient of thermal expansion at zero pressure[α°] are defined. ^ The new derived EoS is tested against the experiments on perovskite and epsilon iron. The Root-mean-square-deviations (RMSD) of the residuals of the molar volume, pressure, and temperature are in the range of the uncertainty of the experiments. ^ Separating the experiments into 200 K ranges, the new EoS was compared to the most widely used finite strain, interatomic potential, and empirical isothermal EoSs such as the Burch-Murnaghan, the Vinet, and the Roy-Roy respectively. Correlation coefficients, RMSD's of the residuals, and Akaike Information Criteria were used for evaluating the fitting. Based on these fitting parameters, the new p-V-T EoS is superior in every temperature range relative to the investigated conventional isothermal EoS. ^ The new EoS for epsilon iron reproduces the preliminary-reference earth-model (PREM) densities at 6100-7400 K indicating that the presence of light elements might not be necessary to explain the Earth's inner core densities. ^ It is suggested that the latent heat of fusion supplies the energy required for overcoming on the viscous drag resistance of the atoms. The calculated energies for melts formed from highly symmetrical packing arrangements correlate very well with experimentally determined latent heat values. ^ The optical investigation of carhonado-diamond is also part of the dissertation. The collected first complete infrared FTIR absorption spectra for carhonado-diamond confirm the interstellar origin for the most enigmatic diamonds known as carbonado. ^

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The organic and isotopic geochemical study of two sediment cores (KH-79-3, L-3, and KH-79-3, C-3) from the Oki Ridge in the Japan Sea has revealed that total organic carbon (TOC) mass accumulation rates are extremely high in the 12-11 ka (calendar age) interval and TOC in the sections in the 24-17 ka interval is depleted in 13C by 3.5? relative to Holocene sediments. Alkenone sea surface temperature (SST) shows a decrease from 18° to 14°C from 17.5 to 11.6 ka and a sharp increase from 14° to 19°C from 11.6 to 11.1 ka. The SST changes are associated with the inflow of cold seawater with the vertical water mixing and the inflowof warm Tsushima Current into the Japan Sea. The d13C values for both 24-methylcholesta-5,22-dien-3?-ol (diatom marker) and dinosterol (dinoflagellate marker), are at their minimum from 24 to 17 ka, while those for long-chain alkenones are not. The theoretical considerations on d13C for biomarkers suggest low photosynthetic carbon demand of diatoms and dinoflagellates from 24 to 17 ka.

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Knowledge and its management have been respectively accepted as a critical resource and a core business competency. Despite that literature proves the existence of a gap between the theoretical considerations of Knowledge Management (KM) and their efficient application. Such lacking, we argue, derives from the missing link between a framework of Knowledge Management and the particular methods and guidelines of its implementation. In an attempt to bridge this gap, an original, process- based holistic Knowledge Management framework is proposed, aiming to address the problem of knowledge management application and performance by utilising a set of well accepted Enterprise Modelling (EM) methods and tools.

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Diversas consideraciones históricas e ideológicas han impedido la difusión de la obra fundamental de Sraffa Producción de mercancías por medio de mercancías. La obra de Sraffa ha sido estudiada fundamentalmente en sus aspectos matemáticos por economistas tales como Garegnani, Abraham-Frois, Pasinetti, Steedman, Kurz, Roncaglia, etc. pero sin desarrollar apenas sus aspectos teóricos y económicos. En este artículo se hacen algunas consideraciones sobre posibles desarrollos del libro de Sraffa a partir de su propio esquema de pensamiento.

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This collection is the result of theoretical considerations made in the education field with emphasis on the teacher’s professional development. The diversity of authors, which came from distinctive higher education institutions located in Brazil and some arising from international context, reveals a multiplicity of relations between the themes that blend the centrality of “Rede de Aprendizado em Foco”. The studies and researches are organized around three themes: teacher’s learning in initial training and professional integration; teacher learning’s evaluations process and policies; and teacher’s professional development. The professionality’s formation in a period of deep and complex transformations in the social and educational scenarios is projected as a big challenge, especially when it is understood that a person is not born as a teacher, but it is constituted as such by processes that occur over a long period. The contact with the professional practice stands as an essential element in the context of teacher training, which in the course of professional learning experience different stages of training. The one that should be highlighted would be the learning moments that involve teaching’s practices. Thus, the main point of this work was based on the reflection of the teacher’s formative processes from the initial training to the professional development going through the teaching practice, which is considered as the beginning of the relationship between theoretical and practical knowledge in the context of educational reality and reporting formative experiences that have contributed to this training.

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Although the transition metal chemistry of many dialkylamido ligands has been well studied, the chemistry of the bulky di(tert-butyl)amido ligand has been largely overlooked. The di(tert-butyl)amido ligand is well suited for synthesizing transition metal compounds with low coordination numbers; such compounds may exhibit interesting structural, physical, and chemical properties. Di(tert-butyl)amido complexes of transition metals are expected to exhibit high volatilities and low decomposition temperatures, thus making them well suited for the chemical vapor deposition of metals and metal nitrides. Treatment of MnBr₂(THF)₂, FeI₂, CoBr₂(DME), or NiBr₂(DME) with two equivalents of LiN(t-Bu)2 in benzene affords the two-coordinate complex M[N(t-Bu)₂]₂, where M is Mn, Fe, Co, or Ni. Crystallographic studies show that the M-N distances decrease across the series: 1.9365 (Mn), 1.8790 (Fe), 1.845 (Co), 1.798 Å (Ni). The N-M- N angles are very close to linear for Mn and Fe (179.30 and 179.45°, respectively), but bent for Co and Ni (159.2 and 160.90°, respectively). As expected, the d⁵ Mn complex has a magnetic moment of 5.53 μΒ that is very close to the spin only value. The EPR spectrum is nearly axial with a low E/D ratio of 0.014. The d⁶ Fe compound has a room temperature magnetic moment of 5.55 μΒ indicative of a large orbital angular momentum contribution. It does not exhibit a Jahn-Teller distortion despite the expected doubly degenerate ground state. Applied field Mössbauer spectroscopy shows that the effective internal hyperfine field is unusually large, Hint = 105 T. The magnetic moments of Co[N(t-Bu)₂]₂ and Ni[N(t-Bu)₂]₂ are 5.24 and 3.02 μΒ respectively. Both are EPR silent at 4.2 K. Treatment of TiCl₄ with three equivalents of LiN(t-Bu)2 in pentane affords the briding imido compound Ti₂[μ-N(t-Bu)]₂Cl₂[N(t-Bu)₂]₂ via a dealkylation reaction. Rotation around the bis(tert-butyl)amido groups is hindered, with activation parameters of ΔH‡ = 12.8 ± 0.6 kcal mol-1 and ΔS‡ = -8 ± 2 cal K-1 ·mol-1, as evidenced by variable temperature 1H NMR spectroscopy. Treatment of TiCl₄ with two equivalents of HN(t-Bu)₂ affords Ti₂Cl₆[N(t-Bu)₂]₂. This complex shows a close-contact of 2.634(3) Å between Ti and the carbon atom of one of the CH₃ substituents on the tert-butyl groups. Theoretical considerations and detailed structural comparisons suggest this interaction is not agostic in nature, but rather is a consequence of interligand repulsions. Treatment of NiI₂(PPh3)₂ and PdCl₂(PPh₃)₂ with LiN(t-Bu)₂in benzene affords Ni[N(t-Bu)₂](PPh₃)I and Pd₃(μ₂-NBut₂)2(μ₂-PPh₂)Ph(PPh₃) respectively. The compound Ni[N(t-Bu)₂](PPh₃)I has distorted T-shape in geometry, whereas Pd₃(μ₂-NBut₂)₂(μ₂-PPh₂)Ph(PPh₃) contains a triangular palladium core. Manganese nitride films were grown from Mn[N(t-Bu)₂]₂ in the presence of anhydrous ammonia. The growth rate was several nanometers per minute even at the remarkably low temperature of 80⁰C. As grown, the films are carbon- and oxygen-free, and have a columnar morphology. The spacings between the columns become smaller and the films become smoother as the growth temperature is increased. The composition of the films is consistent with a stoichiometry of Mn₅N₂.

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El presente texto ofrece algunas reflexiones teóricas y visionesdel autor sobre la relación del hombre de hoy con el fenómeno dela comunicación digital, también conocida como comunicaciónvirtual, a través de Internet, unas reflexiones que aparecen deltrabajo investigativo sobre el modelo convergente del canalde televisión pública Telemedellín, y en las que se explora elpanorama de las relaciones del hombre con el otro, consigomismo y con las cosas, desde la mediación de la computadora.Por otro lado, indaga sobre la composición de las redes socialesy su producto, la comunidad virtual, lugar en el que se producenlos intercambios e interrelaciones humanas. Y finalmente,intenta mostrar el desasosiego del hombre de la época actual,encontrándolo como un ser solitario que lucha por un lugar enel mundo.