989 resultados para AB-DTPA
Resumo:
The metastable phase diagram of the BCC-based ordering equilibria in the Fe-Al-Mo system has been calculated via a truncated cluster expansion, through the combination of Full-Potential-Linear augmented Plane Wave (FP-LAPW) electronic structure calculations and of Cluster Variation Method (CVM) thermodynamic calculations in the irregular tetrahedron approximation. Four isothermal sections at 1750 K, 2000 K, 2250 K and 2500 K are calculated and correlated with recently published experimental data on the system. The results confirm that the critical temperature for the order-disorder equilibrium between Fe(3)Al-D0(3) and FeAl-B2 is increased by Mo additions, while the critical temperature for the FeAl-B2/A2 equilibrium is kept approximately invariant with increasing Mo contents. The stabilization of the Al-rich A2 phase in equilibrium with overstoichiometric B2-(Fe,Mo)Al is also consistent with the attribution of the A2 structure to the tau(2) phase, stable at high temperatures in overstoichiometric B2-FeAl. (C) 2009 Elsevier Ltd. All rights reserved.
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We present our theoretical results for the structural, electronic, vibrational and optical properties of MO(2) (M = Sn, Zr, Hf and Ti) obtained by first-principles calculations. Relativistic effects are demonstrated to be important for a realistic description of the detailed structure of the electronic frequency-dependent dielectric function, as well as of the carrier effective masses. Based on our results, we found that the main contribution of the high values calculated for the oxides dielectric constants arises from the vibrational properties of these oxides, and the vibrational static dielectric constant values diminish with increasing pressure. (c) 2008 Elsevier B.V. All rights reserved.
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Ab initio calculations based on the density functional theory (DFT) are used to investigate the electronic and optical properties of sillimanite. The geometrical parameters of the unit cell, which contain 32 atoms, have been fully optimized and are in good agreement with the experimental data. The electronic structure shows that sillimanite has an indirect band gap of 5.18 eV. The complex dielectric function and optical constants, such as extinction coefficient, refractive index, reflectivity and energy-loss spectrum, are calculated. The optical properties of sillimanite are discussed based on the band structure calculations. It is shown that the O-2p states and Al-3s, Si-3s states play the major role in optical transitions as initial and final states, respectively. (C) 2011 Elsevier B.V. All rights reserved.
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We report the partitioning of the interaction-induced static electronic dipole (hyper)polarizabilities for linear hydrogen cyanide complexes into contributions arising from various interaction energy terms. We analyzed the nonadditivities of the studied properties and used these data to predict the electric properties of an infinite chain. The interaction-induced static electric dipole properties and their nonadditivities were analyzed using an approach based on numerical differentiation of the interaction energy components estimated in an external electric field. These were obtained using the hybrid variational-perturbational interaction energy decomposition scheme, augmented with coupled-cluster calculations, with singles, doubles, and noniterative triples. Our results indicate that the interaction-induced dipole moments and polarizabilities are primarily electrostatic in nature; however, the composition of the interaction hyperpolarizabilities is much more complex. The overlap effects substantially quench the contributions due to electrostatic interactions, and therefore, the major components are due to the induction and exchange induction terms, as well as the intramolecular electron-correlation corrections. A particularly intriguing observation is that the interaction first hyperpolarizability in the studied systems not only is much larger than the corresponding sum of monomer properties, but also has the opposite sign. We show that this effect can be viewed as a direct consequence of hydrogen-bonding interactions that lead to a decrease of the hyperpolarizability of the proton acceptor and an increase of the hyperpolarizability of the proton donor. In the case of the first hyperpolarizability, we also observed the largest nonadditivity of interaction properties (nearly 17%) which further enhances the effects of pairwise interactions.
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The electronic and optical properties of grossular garnet are investigated using density functional theory (DFT) within generalized gradient approximation (GGA). The calculated lattice parameters are in good agreement with the experiment data. The electronic structure shows that grossular has a direct band gap of 5.22 eV. The dielectric functions, reflective index, extinction coefficient, reflectivity and energy-loss spectrum are calculated. The optical properties of grossular are discussed based on the band structure calculations. The O 2p states and Si 3s play a major role in these optical transitions as initial and final states, respectively. The absorption spectrum is localized in the ultraviolet range between 30 and 250 nm. Finally, we concluded that pure grossular crystal does not absorb radiation in the visible range. (c) 2009 Elsevier B.V. All rights reserved.
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Structural and thermodynamic stabilities of monomers and dimers of trialkylphosphine oxides (TRPO) were Studied using quantum chemistry calculations. Density functional theory calculations were carried Out and the structures Of four TRPO have been determined: TMPO (methyl; R = CH(3)), TEPO (ethyl; R = CH(3)CH(2)), TBPO (n-butyl; R = CH(3)(CH(2))(3)), and TOPO (n-octyl; R = CH(3)(CH(2))(7)). TRPO homodimers were investigated considering two isomeric possibilities for each dimer. Relative binding energies and the enthalpic and entropic contributions to the Gibbs free energy were Calculated for all dimers. The formation of dimers from the individual monomeric TRPO species as a function of temperature was also analyzed. (C) 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109: 250-258, 2009
Resumo:
The conformational features of three 2-sulphur-substituted cyclohexanone derivatives, which differ in the number of sulphur-bound oxygen atoms, i.e. zero (I), one (II) and two (III), were investigated by single crystal X-ray crystallography and geometry optimized structures determined using Hartree-Fock method. In each of (I)-(III) an intramolecular S center dot center dot center dot O(carbonyl) interaction is found with the magnitude correlated with the oxidation state of the sulphur atom, i.e. 2.838(3) angstrom in (I) to 2.924(2) angstrom in (II) to 3.0973(18) angstrom in (III). There is an inverse relationship between the strength of this interaction and the magnitude of the carbonyl bond. The supramolecular aggregation patterns are primarily determined by C-H center dot center dot center dot O contacts and are similarly influenced by the number of oxygen atoms in the molecular structures. Thus, a supramolecular chain is found in the crystal structure of (I). With an additional oxygen atom available to participate in C-H center dot center dot center dot O interactions, as in (II), a two-dimensional array is found. Finally, a three-dimensional network is found for (III). Despite there being differences in conformations between the experimental structures and those calculated in the gas-phase, the S center dot center dot center dot O interactions persist. The presence of intermolecular C-H center dot center dot center dot O interactions involving the cyclohexanone-carbonyl group in the solid-state, disrupts the stabilising intramolecular C-H center dot center dot center dot O interaction in the energetically-favoured conformation. (I): C(12)H(13)NO(3)S, triclinic space group P (1) over bar with a = 5.392(3) angstrom b = 10.731(6) angstrom, c = 11.075(6) angstrom, alpha = 113.424(4)degrees, beta = 94.167(9)degrees, gamma = 98.444(6)degrees, V = 575.5(6) angstrom(3), Z = 2, R(1) = 0.052; (II): C(12)H(13)NO(4)S, monoclinic P2(1)/n, a = 7.3506(15) angstrom, b = 6.7814(14) angstrom, c = 23.479(5) angstrom, beta = 92.94(3)degrees, V = 1168.8(4) angstrom(3), Z = 4, R(1) = 0.046; (III): C(12)H(13)NO(5)S, monoclinic P2(1)/c, a = 5.5491(11) angstrom, b = 24.146(3) angstrom, c = 11.124(3) angstrom, beta = 114.590(10)degrees, V = 1355.3(5) angstrom(3), Z = 4, R(1) = 0.051.
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The kinetics of hydrolysis of 1,8-N-butyl-naphthalimide (1,8-NBN) to 1,8-N-butyl-naphthalamide (1,8-NBAmide) and of 2,3-N-butyl-naphthalimide (2,3-NBN) to 2,3-N-butyl-naphthalamide (2,3-NBAmide), as well as the formation of the respective anhydrides from the amides were investigated in a wide acidity range. 1,8-NBN equilibrates with 1,8-NBAmide in mild alkali. Under the same conditions 2,3-NBN quantitatively yields 2,3-NBAmide. Over a wide range of acidities the reactions of the 1,8- and 2,3-N-butyl-naphthalamides (or imides) yield similar products but with widely different rates and at distinct pH`s. Anhydride formation in acid was demonstrated for 1,8-NBAmide. The reactions mechanisms were rationalized in the manifold pathways of ab initio calculations. The differences in rates and pH ranges in the reactions of the 1,8- and 2,3-N-butyl-naphthalamides were attributed to differences in the stability of the tetrahedral intermediates in alkali as well as the relative stabilities of the five and six-membered ring intermediates. The rate of carboxylic acid assisted 1,8-N-Butyl-naphthalamide hydrolysis is one of the largest described for amide hydrolysis models. Copyright (C) 2010 John Wiley & Sons, Ltd.
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Pappersmakulatur uppstår i tryckpressarna, men orsakerna finns i företagets alla funktioner. För ett framgångsrikt förbättringsarbete med att minska makulaturen krävs därför att all personal är engagerad.Examensarbetet utfördes på Bobergs Tryckeri AB i Falun, ett familjeägt företag med 60 anställda, som producerar personifierad direktreklam och blanketter. Syftet var att undersöka hur pappersmakulaturen kan minska och målet var att hitta orsaker samt ge förslag på åtgärder för att minska den.Genom intervjuer med personalen kartlades produktionssprocessen och utifrån det utarbetades förbättringsförslag. Exempel på förbättringsförslag är att kontinuerligt mäta och rapportera makulaturen, förbättra kommunikationen mellan avdelningarna och utveckla färgstyrningen. Litteraturstudier och kontakter med nyckelpersoner inom branschorganisationer och andra liknande företag, var till stor hjälp i arbetet. Fördjupningsdelen i projektet har sin grund i boken The Printer’s Guide to Waste Reduction av Tim Dalton.
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För att visa på nyttan av vad ett användartest kan erbjuda i samband med utveckling av en webbplats har vi i denna rapport tagit med alla stegen fram till och med utveckling i Vattenfallsmetoden, som är den metod som vi använt oss av. De föregående stegen i metoden är förstudie, analys och design. Förstudien valde vi att genomföra som ett användartest för att få fram vad användarna verkligen efterfrågade. Vi analyserade sedan resultatet av användartestet och gjorde en sammanfattning, men i den tog vi även hänsyn till det material som vi samlat in och vad de ansvariga på Hedlunds Hus AB efterfrågade. Detta resulterade i en lista med prioriterade funktioner och innehåll, som vi sedan utgick ifrån vid utveckling av webbplatsen. Vid utveckling av webbplatsen togs även hänsyn till det material som vi samlat in om webbutformning/design. Att använda sig av ett användartest i förstudiefasen tycker vi är ett bra sätt för att få fram vad användarna efterlyser och inte vad vi som webbutvecklare själva tror att användarna behöver.
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This Degree Project is a cooperativ work with the advertising agency PAX in Falun and the industrial companyRemote Control, who constructs and sells actuators for the global market.The assignment concerns bringing out a graphic profile, or with another expression a Design Management, forRemote Control AB graphic materials. Remote Control AB has a quality certification ISO 9000 and is workingwith, when this report was wrote, an environment certification ISO 14001.The Company has been paid attention to Internet and other media.The supervisors are familiar to that Design Management is a soon coming competition element, like quality andenvironment management.This Degree project contains research, analysis and the construction of graphic material. The research has beencommitted most of the time to trace the customer, the market and the competitor, because its the most importantphase. It’s also important looking at competitor’s way of working with marketing management, so you can separatethem from the own company.
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This thesis work has introduced process orientation at the printing company Color Print Sweden AB. The outcome ofthis work is a survey of the work flow at the prepress department. To visualise the production process at the companya comprehensive mapping of the main process, order-to-delivery, has been made. The work has detected a couple ofcritical elements in the existing process. These elements are the following: initial check of material delivered to the prepressdepartment as well as the control made of the plotter print-out, digital test print and plate. To guarantee the qualityof the prints it is very important that the work made in the prepress department is optimized. This survey can thereforebe used as a basis for continuous improvement in the processes at Color Print Sweden AB. This work has alsoresulted in a template that Color Print Sweden AB can use to design routine descriptions to ensure that specific worktasks are performed the right way by everyone and all the time.
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The purpose of this degree project is to come up with a new package to Renat Brännvin for »Vin & SpritAB« and make the product more attractive on the market of bars, restaurants and hotels. The commissionhas included to decide the material of the package, whether it´s possible to manufacture the productand to make an estimation of the costs.The conditions that »Vin & Sprit AB« set up was to make the product attractive to a younger targetgroup, in this case people from 20 to 40 years old. As Renat Brännvin is considered to be a product of firstclass it´s of great importance that the package reflects the look of a premium product.At first we looked at the history of the company »Vin & Sprit AB« and Renat Brännvin. We decidedthat the package schould consist of a bottle, glasses and a device used when serving the liquor. To getinspiration before sketching we studied different kinds of bottles, glasses and serving devices. We madea lot of different sketches to start with after which we consult with Ingrid Florén – our supervisor from»Vin & Sprit AB« – agreed on one. That one we developed and we made more accurate sketches in 3DStudioMAX.At last we looked at the opportunities to produce the bottle by questioning different manufacturers. Wewanted to know the limitations to consider when making a bottle.
Resumo:
Bobergs printing house in Falun has during some time had problems regarding deposits on blankets intheirs Müller Martini UV-printing presses. Deposits appear in both image areas and non-image areas.These areas have been analyzed and the deposits on non-image areas contain chalk, clay and talc. Thequestion remains how these material bond to the blanket surface. The chalk and clay comes from thepaper. The talc comes from the ink. Deposits from image areas contain pigment and talc from the printingink. The dampening water has also been analyzed. The result shows some sort of problem with thehardness regulator for the clean water. The pH-level should be increased a few steps.