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Análisis y propuestas de modernización del estatuto de la inversión extranjera, decreto ley 600Herrera Gómez-Barris, Paula Ximena January 2008 (has links)
Tesis (magíster en derecho) / El objetivo de esta tesis es analizar el Estatuto de Inversión Extranjera para proponer adecuaciones que le permitan responder de mejor forma a la mayor competencia que se enfrenta a nivel internacional en la atracción de capitales externos. Chile debe adaptarse a los tiempos actuales, flexibilizando los mecanismos de incentivo para el capital extranjero, para que nuestro país pueda continuar destacándose por su capacidad para atraer inversiones foráneas.
La tesis consta de cinco capítulos. El primero describe el origen del Estatuto de Inversión Extranjera y sus principales principios. El segundo capítulo describe el texto del Estatuto actualmente vigente. El tercer capítulo presenta las observaciones de destacados juristas que representan a grandes inversionistas extranjeros en Chile, los que fueron entrevistados por la autora, las opiniones de estos abogados no se individualizan ya que las entrevistas se realizaron en un marco de confidencialidad. En el cuarto capítulo se efectúa un análisis del texto vigente y de las propuestas planteadas por los juristas entrevistados. En el capítulo quinto se concluye y se presentan recomendaciones de modificaciones al Decreto Ley N° 600. La tesis además contiene un anexo en el que se presenta el texto del Decreto Ley N° 600 vigente en la actualidad.
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Sind Studierende ein lohnendes Kundensegment für Versicherungsunternehmen? Ergebnisse einer empirischen Studie an österreichischen Universitäten.Dornhelm-Rauschmeier, Flora, Fitzsimons, Elsa-Maria, Eszler, Erwin January 2009 (has links) (PDF)
Kaufen Studierende Versicherungen? Wie viel Geld geben Sie dafür aus? Wie schätzen Studierende ihre Erfahrungen mit Versicherungsunternehmen ein? Was halten Sie überhaupt von der Versicherungswirtschaft? Was ist Ihnen wichtig? - Fragen, denen eine im März 2009 an der Wirtschaftsuniversität Wien fertig gestellte Diplomarbeit nachging. / Series: Arbeitspapiere zum Tätigkeitsfeld Risikomanagement und Versicherung / Institut für Versicherungswirtschaft
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The development of Microwave Thermal Analysis (MWTA)and its application to the study of carbons and other materialsHamilton, Ian January 2009 (has links)
This research involves the development of a totally new approach to thermal analysis in which microwave energy is used not only to heat the sample but also to detect thermally induced transformations via the effects of changes in its dielectric properties. Use of these properties, rather than the more usual mass or enthalpy changes of conventional thermal analysis, provide a unique insight into thermal processes. Microwave thermal analysis (MWTA) is a technique for studying the efficiency of the conversion of microwave to thermal energy by measuring the microwave power-temperature relationship for different materials. Power/temperature verses time profiles in some cases give an indication of physical and chemical changes occurring in the sample, via changes in the dielectric constant. An instrument for performing microwave thermal analysis (MWTA) has been designed, constructed and applied to an extensive range of chemical systems exhibiting a variety of physicochemical transformations, including melting, decomposition and solid-solid phase changes. MWTA has been shown to provide both qualitative and quantitative information with sample masses ranging from the analytical (1 to 20 mg) to semi-preparative (0.5 to 5.0 g) scales. It has been demonstrated that MWTA can be used in conjunction with complementary techniques such as differential thermal analysis (DTA) and X-ray powder diffraction (XRD) to provide additional data. MWTA has the potential to be extended to incorporate some of the latest developments in thermal analysis, including methods involving temperature modulation and evolved gas analysis. MWTA has the potential to have applications in the design of industrial processes by providing detailed information on the effect of microwave radiation on both physical (e.g. phase changes) and chemical processes.
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Synthesis of polydentate ligands and the formation of heterometallic and circular helicatesWhitehead, Martina January 2010 (has links)
Described herein, is the synthesis and coordination chemistry of seven novel ligands L1 - L7. These ligands form metallosupramolecular assemblies upon coordination of transition metal ions resulting in heterodi- and hetreotrimetallic double helicates and penta- and tetranuclear cyclic helicates. Described in Chapter 2 is a new class of ditopic segmental pyridyl-thiazole(py-tz) N-donor ligands L1 - L3. Reaction of L1 with ZnII ions results in the formation of a dinuclear double helicate [Zn2(L1)2]4+. Reaction of L2 with either ZnII or HgII results in the formation of the L2-containing dinuclear double helicates [Zn2(L2)2]4+ and [Hg2(L2)2]4+. However, reaction with both ZnII or HgII results in the sole formation of the heterodimetallic helicate [HgZn(L2)2]+. Both metal ions are 6-coordinate but the HgII ion is coordinated by the two py-tz-py units whereas the ZnII ion is coordinated by the py-py-tz domain. The reason that these isomeric sites have different preferences for each of the metal ions is due to the position of the thiazole unit within the terdentate domains, as in the central position the thiazole unit increases the “bite angle” of the donor unit making it more suitable for the larger HgII. Conversely the py-py-tz domain has a smaller bite angle and it more suited to the smaller ZnII ion. Reaction of L3 with ZnII, HgII and CuII results in the formation of a heterometallic trinuclear double helicate [HH-[HgCuZn(L3)2]5+. In a similar fashion to L2, the ZnII ion coordinated by the terdentate py-py-tz domain and the HgII coordinated by the py-tz-py domain. The central bipyridine unit coordinates the tetrahedral CuII ion resulting in the first reported example of a heterotrimetallic double helicate. Described in Chapter 4 is a potentially hexadentate N-donor ligand L4, which upon reaction with CdII results in the formation of a dinuclear double helicate [Cd2(L4)2]4+. In this structure the ligand partitions into two tridentate tz-py-py domains each of which coordinate a different metal ion. However, reaction of L4 with ZnII results in the formation of a pentanuclear circular helicate [Zn5(L4)5]10+, with all the five zinc ions adopting a octahedral coordination geometry arising from the coordination of the two tridentate tz-py-py domains from two different ligand strands. This difference in structure is attributed to unfavourable steric interactions which prevent the formation of [Zn2(L4)2]4+ but these unfavourable interactions are not present with the larger Cd2+ ion. Described in Chapter 5 are the potentially pentadentate and tetradentate ligands L5 and L6, respectively. The ligand L5 contains both a bidentate and tridentate binding site separated by a phenylene spacer unit. Reaction of L5 with CuII results in the formation of a pentanuclear circular helicate [Cu5(L5)5]10+. Each of the CuII ions adopts a 5-coordinate geometry formed by coordination of the bidentate domain of one ligand strand and the tridentate domain of a different ligand. As a result this gives a head-to-tail pentanuclear double helicate. Reaction of L6 and L4 (Chapter 4) with CuII results in the formation of a heteroleptic pentanuclear circular helicate [Cu5(L4)3(L6)2]10+. The cyclic array consists of five copper(II) ions, coordinated by three strands of L4 and two strands of L6. In this species four of the CuII adopt a 5- coordinate geometry arising from coordination of a tridentate domain from L4 and a bidentate domain from L6. The remaining copper ion is coordinated by two tridentate domains from L4 resulting in an octahedral coordination geometry. Described in Chapter 6 is the potentially hexadentate N-donor ligand L7 which comprises of two identical tridentate py-py-tz N3 binding domains separated by a pyrene unit. Reaction of L7 with ZnII results in the formation of a tetranuclear circular helicate [Zn4(L7)4]8+ with all four zinc metal ions adopting a six-coordinate geometry arising from the coordination of two tridentate pypy- tz units from two different ligand strands. The formation of this lower nuclearity species (e.g. tetranuclear rather than pentanuclear) is attributed to the p-stacking between the pyrene unit and the py-py-tz domain.
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Designing a competency framework for logistics executives : the case of the ready-made garments manufacturers in EgyptEl-Zarka, Sara January 2010 (has links)
The ready-made garments (RMG) manufacturing industry in Egypt is one of the main industries that supports the Egyptian economy through exports‟ earnings. Egypt‟s RMG exports are considerably less in quantity than other RMG exporting countries despite the advantages that Egypt has in terms of availability of high quality raw materials „cotton‟, the geographical proximity to main RMG importers and duty free trade agreements. Among the factors found to affect the competitiveness of Egypt‟s RMG exports are the lack of training, and the lack of skilled labour and management. This research develops a competency framework - a tool that can assist RMG manufacturing companies in Egypt to identify the skills needed for effective job performance and to define the skills deficiencies that would require training. This competency framework focuses on logistics executives in RMG manufacturing companies, as competent logistics executives have been shown to play a vital role in supporting the competitive advantage of organisations. The competency approach had not previously been used in research to identify the competencies needed for logistics executives in any industry, including the RMG industry. Moreover, very little work has been carried out on investigating the skills of logistics executives in developing countries, nevertheless in the Middle East. To create this competency framework, methodological triangulation was used through the use of questionnaires, content analysis and semi-structured interviews. The online questionnaire targeted a sample of logistics executives in RMG companies in Egypt to determine the tasks they consider important for effective job performance. The content analysis was performed on skills-related research to collect the skills and knowledge elements acknowledged in the literature to create logistics competencies. The output of the questionnaire and the content analysis was then used in a semi-structured interview with a senior merchandiser and development manager in an Egyptian RMG manufacturing company to provide an example of a completed competency framework. This thesis seeks to make an original contribution to knowledge by creating a competency framework template that RMG manufacturing companies in Egypt can use to identify the competencies and detect the skills deficiencies of logistics executives. This contribution would not only benefit the RMG manufacturing companies in Egypt, but it could also be of use to RMG exporters in developing countries which suffer from similar skills and training problems. This research is also a contribution in that it emphasises the role of logistics executives towards supporting Egypt‟s RMG exports, an angle which has not previously been explored, as earlier research focused on other aspects that supported the competitiveness of Egypt‟s RMG exports such as trade regulations. Moreover, acknowledging the role of logistics executives in this study could draw the attention of other industrial sectors in Egypt to consider the role of competent logistics executives towards supporting companies‟ performance.
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Molecular modelling of the complex polysaccharide heparan sulphateSwift, Simone January 2011 (has links)
Heparan Sulphate plays an important role in many life processes and so an understanding of its role as a universal co-receptor is of great importance. Traditionally oligosaccharides derived from the related molecule heparin have been at the forefront of molecular drug design, due to its similarity in structure and function. To obtain a more complex and detailed picture of the role of HS in structural biology further complex work must be undertaken on HS. Here in this study a number of HS derived octasaccharides have been purified. Alongside this is work carried on HS derived decasaccharides, of which all have undergone extensive molecular modelling simulations. The role of the Iduronates in the HS structure, at monosaccharide level has indicated a major role for these structures in biological activity. Further work has indicated the level of sulphation is also a requirement which in turn influences conformational behaviour. Up until now this has only really been studied at the monosaccharide level and so this study has generated a number of different HS models which can confirm the importance of iduronate conformation in biological activity. Not only that but it has also been identified that certain torsional geometries within the glycosidic bonds between monosaccharides also has a major influence on conformation. Local deviations in the molecular modelling data suggest there is a slight difference between active and inactive oligosaccharides with the ability to bind and activate the HS:FGF2:FGFR IIIc complex. The implications of these and other structural insights are discussed with the implication heavily towards a combination of both torsional geometry and iduronate conformation in biological activity. To further aid our understanding HS dp10 oligosaccharides were docked into a FGF2 which was in a complex with a heparin hexasaccharide. Docking experiments were carried in order to attain structural information on the binding of these molecules. The Goodger oligosaccharides were docked into the X-ray crystal structure and were chosen specifically for their iduronate conformation or the torsional geometry.
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Phase behaviour of oat β-glucan/sodium caseinate mixturesAgbenorhevi, Jacob Kwaku January 2011 (has links)
Oat β-glucan is a water soluble polysaccharide which has been approved as a functional bioactive ingredient. In this thesis, β-glucan was successfully isolated from oat flour and samples of different molecular weights were produced. The structural features and molecular weights(Mw) were characterized by 13C–NMR spectroscopy and high performance size-exclusion chromatography, respectively. The rheological properties and microstructure of aqueous oat β-glucan solutions were investigated by rheometry and atomic force microscopy (AFM),respectively. The samples with β-glucan content between 78-86 % on a dry weight basis had Mw, intrinsic viscosity ([η]) and critical coil overlap concentration (c*) in the range of 142 - 2800 x 103 g/mol, 1.7 - 7.2 dL/g and 0.25 - 1.10 g/dL, respectively. The flow and viscoelasticvbehaviour was highly dependent on Mw and on the concentration of the β-glucan solutions. AFM images revealed the formation of cluster or aggregates linked via individual polymer chains scattered heterogeneously throughout the system. The aggregate size was also dependent on molecular weight of the samples and influences the rheological behaviour of β-glucan solutions. The isothermal phase behaviour at 5 oC of β-glucan/sodium caseinate mixtures were investigated by means of phase diagram construction, rheometry, electrophoresis and fluorescence microscopy. Phase diagrams indicated that the compatibility of the β-glucan/sodium caseinate system increases as β-glucan Mw decreases. Images of the mixtures taken at various biopolymer concentrations revealed phase separation with the presence of β-glucan aggregates,whose size depends on Mw and concentration. At the same protein concentration in the mixtures, the viscosity increases with increasing Mw and concentration of β-glucan. However, the results also revealed that in the state of thermodynamic equilibrium with comparable polymer concentrations in mixture, the lower Mw samples yielded similar or higher viscosity. At equivalent hydrodynamic volume of β-glucan component in the mixture, all the samples exhibited similar viscosity/flow behaviour. A deviation dependent on the protein concentration was observed for the high Mw sample in the concentrated regime due to the size of the β-glucan aggregates formed. Results demonstrate that by controlling the structural features of β-glucan in mixture with sodium caseinate, informed manipulation of rheological properties in these systems can be achieved.
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Drosophila melanogaster as a model for molybdo-flavoenzyme mediated protection against chemical and physical stressAl Salhen, Khaled S. January 2012 (has links)
Aldehyde oxidase (AO) and xanthine oxidoreductase (XOR) are molybdo-flavoenzymes (MFEs) involved in the oxidation of hundreds of endogenous and exogenous aldehydes and N-heterocyclic compounds many of which are drugs, vitamins and environmental pollutants. Mutations in the XOR and molybdenum cofactor sulfurase (MCS) genes result in a deficiency of XOR or dual AO/XOR deficiency respectively. At present despite AO and XOR being classed as detoxification enzymes the definitive experimental proof of this has not been assessed in any animals thus far. The aim of this project was to evaluate ry and ma-l strains of Drosophila melanogaster as experimental models for XOR and dual AO/XOR deficiencies respectively and to determine if MFEs have a role in the protection against chemical and physical stress. An additional aim was to determine the molecular basis for deficiency in ma-l strains by cloning and sequencing the MCS gene. Spectrophotometric and HPLC assays demonstrated that Drosophila AO and XOR were able to catalyse the biotransformation of numerous substrates of the well-scrutinised mammalian orthologs. These included several aromatic aldehydes and N-heterocyclic pollutants, drugs and endogenous vitamins. Investigation of the enzyme activity in ry strain revealed a compromised ability to biotransform several XOR substrates that reflected the situation in human hereditary xanthinuria type I. Both ma-l strains were found to be unable to biotransform all AO substrates tested. These results confirmed that Drosophila were good experimental models for testing the role of MFEs as detoxification enzymes. In order to test the role of the enzymes in chemoprotection, MFE substrates were administered to Drosophila in media and survivorship monitored. It was demonstrated that several methylated xanthines were toxic to XOR-deficient strains. In addition a range of AO substrates including N-heterocycles and aldehydes were significantly more toxic to ma-l AO-null strains. This study therefore provides definitive proof that both AO and XOR are involved in detoxification. Investigations to determine the effect of MFE deficiencies on lifespan revealed that ry and ma-l strains had significantly reduced lifespan when compared with the wild type strain with the mean lifespan being reduced approximately 60% and 30% respectively ii in these strains. The effect the MFE deficiencies have on heat and cold stress indicated that ry and ma-l strains had significantly reduced ability to survive, with the survivorship of the AO-null ma-l strain being most compromised in these conditions. The effect of the toxic chemicals, lifespan and temperature stress were rescued in ry mutant animals that had the normal ry (XOR) gene reinserted by transgenesis. Cloning and DNA sequencing of the MCS gene in the ma-l strains revealed that the mal-1 and mal-f1 strains had a 6 bp insertion and a 23 bp deletion in exon 4 respectively that are predicted to lead to alterations of the deduced MCS protein structure, thus explaining the dual AO/XOR deficiency in these strains.
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The study of heterogeneous catalysts for biodiesel synthesisAndrijanto, Eko January 2012 (has links)
A study in search of new heterogeneous catalysts that can be used in place of homogeneous catalysts for biodiesel synthesis has been carried out. The objective of this study is to investigate and evaluate the use of solid catalysts for transesterification of triglycerides and esterification of free fatty acid for biodiesel synthesis. Two types of heterogeneous catalyst have been studied that are solid acid and solid base. Three different solid acids and two solid bases were explored. The solid acids investigated were sulfonated hypercrosslinked polystyrene resin, sulfonated polyvinyl alcohol and sulfated zirconia. The solid bases were lithium zirconate and composite calcium oxide-magnetite. Sulfonated hypercrosslinked polystyrene resin has been studied in the esterification reaction of oleic acid with methanol and rearrangement of α-pinene to camphene and limonenes. The activity of this catalyst was compared with conventional macroporous polystyrene sulfonic acids such as Amberlyst-15, Amberlyst-35 and Nafion SAC-13 which is a composite of Nafion and silica. The activity of this catalyst is superior to those of Amberlysts and SAC-13 in the esterification of oleic acid. This catalyst also has high reusability at elevated temperature. Sulfonated polyvinyl alcohol catalyst has been studied in the same way the esterification of oleic acid and rearrangement of α-pinene. The activity of the catalyst was compared with sulfonated macroreticular polystyrene resin Amberlyst-35 and Nafion SAC-13. In the esterification reaction, sulfonated polyvinyl alcohol shows a better activity than SAC-13 and the Amberlyst-35 resin catalyst. In the rearrangement/isomerisation reaction, the sulfonated polyvinyl alcohol is the least active. The activity of sulfated zirconia as a solid acid catalyst has been studied in the esterification of oleic acid and in simultaneous esterification- transesterification of a mixture oleic acid and triglycerides. In the simultaneous reaction, the activity of this catalyst was compared with sulfonated polystyrene catalysts (Amberlyst-15 Amberlyst-35 and Purolite D5081) and commercial sulfated zirconia XZO-1720. The result showed that in the transesterification reaction, the sulfated zirconias are more active but in the esterification reaction the sulfonated polystyrene catalysts are better than sulfated zirconia. The effect of calcination temperature on the catalytic activity of the catalyst was also studied. The study shows that 600 oC calcination gives the best catalytic activity. The lithium zirconate is one of the solid base catalysts evaluated in this study. The catalyst was very active in the transesterification of tributyl glycerate with methanol. The effect of calcination temperature on its activity in the transesterification reaction of tributyl glycerate was studied. The study shows that 700 oC calcination yielded the highest catalytic activity which is associated with the formation of the tetragonal phase which gives the highest concentration of basic sites and basic strength. A composite between calcium oxide and magnetite is the last catalyst reported in this study. The study of this catalyst is due to ease of separation by an external magnetic field. The catalytic performance in the transesterification of tributyl glycerate and methanol was studied. The catalytic activity of the catalyst was maximum at the calcination temperature of 700 oC. Loss of catalytic activity and magnetic properties were shown at higher calcination temperature. Despite the relatively high activities found for the catalysts studied, further improvement is needed if the catalysts are to be applied for industrial use. However, sulfonated hypercrossliked polystyrene resin catalysts showed promising activity for the pre-esterification reaction and it is one of the best catalysts for reducing free fatty acid in low grade vegetable oil.
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Synthesis of functional metallosupramolecular complexesCox, Nicola Michelle January 2012 (has links)
This thesis describes three areas of research which involve preparation of novel pyridyl-thiazole-containing ligands and the formation of their complexes with transition metal ions. Chapter 2 describes the preparation, complexation chemistry and photophysical behaviour of ligands L1 and L2 which contain pyrene moieties. The emission properties of pyrene are highly dependent on its environment, and so it was proposed that it could be used as a probe to elucidate solution conformations of complexes. It was shown that incorporation of a pyrene moiety into the ligand strand and subsequent measurement of the emission spectra of its complexes with Cu+ and Cd2+ gave information about their solution state conformations which correlated well with the solid state structures. In Chapter 3, synthesis and coordination complexes of ligands L3 and L4, which contain substituents capable of binding anions, are described. L3 forms a mononuclear complex with Zn(II) which binds two perchlorate anions via the amide groups on the two substituents. However, with Cu(I), L3 and L4 form dinuclear double helicates which have a binding “pocket” at each end of the complex. Both [Cu2(L3)2](ClO4)2 and [Cu2(L4)2](PF6)2 form one-dimensional polymers; the complexes are held together by bridging perchlorate and hexafluorophosphate anions, respectively. Finally, in Chapter 4, allosteric control of the complexation behaviour of ligand L5 is described. L5 contains amine groups on the 3,3’-positions of the bipyridine core which can react with ketones, forming a cyclic aminal product. Reaction with cyclohexanone was used to control the metal specificity of the ligand by restraining the torsion angle between the two pyridine groups and forcing the ligand into planarity. In general, L5 formed dinuclear double helicates with tetrahedral metals and mononuclear complexes with octahedral metals, as expected. Upon reaction with cyclohexanone, mononuclear species were observed with Hg2+, Zn2+, Cd2+ and Ag+. Experiments were then carried out with mixtures of metal ions and two trends were observed: firstly, when L5 is mixed with octahedral and tetrahedral metals, species containing the octahedral metal are favoured. Where two octahedral metals are used species containing the metal with the larger ionic radius are formed preferentially. After reaction with cyclohexanone, only mononuclear species of the octahedral metals are observed in every case.
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