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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Síntesi, caracterització i reactivitat de complexos de Pd(II), Pt(II) i Rh(II) amb lligands pirazòlics N1-substituïts amb grups alcohol, èter i polièter

Boixassa Mallarach, Anna 16 September 2003 (has links)
No description available.
2

Cyclization of indoles and enol ethers with alkynes catalyzed by platinum and gold

Ferrer Llabrés, Catalina 24 January 2008 (has links)
El indol es uno de los heterociclos aromáticos presente en mayor número de productos naturales con propiedades farmacológicas. Aunque se han desarrollado diferentes métodos para sintetizar derivados de indoles, la búsqueda de metodologías para obtener nuevos compuestos es todavía un tema de interés en química orgánica. Un método interesante para sintetizar derivados de indol es la reacción de hidroarilación de alquinos.Hemos encontrado que la hidroarilación intramolecular de de alquinos catalizada por nuevos complejos de Au(I) permite la síntesis de derivados de indol con anillos de siete miembros fusionados en una reacción de tipo 7-exo-dig. Cuando esta misma reacción se lleva a cabo con AuCl3, en lugar de anillos de siete se forman anillos de ocho miembros en un proceso poco frecuente de tipo 8-endo-dig. En algunas ocasiones, también hemos observado la formación de alenos o tetraciclos como resultado de una reacción de fragmentación. Basándonos en resultados experimentales, hemos propuesto un mecanismo para la formación de este tipo de sustratos que consiste en la formación de un enlace C-C en la posición tres del indol, seguido de una migración 1,2, en una reacción de tipo Friedel-Craft. Hemos desarrollado la versión intermolecular de la reacción entre indoles y alquinos obteniendo una amplia diversidad de productos en función de la sustitución en el indol y el alquino.En el segundo capítulo de la Tesis esta metodología sintética ha sido aplicada al estudio de la síntesis total de los productos naturales lundurinas A-D, cuya estructura posee una indoloazocina. Mediante la ciclación catalizada por AuCl3 del sustrato adecuado hemos conseguido sintetizar la estructura tetracíclica característica de esta familia de compuestos.Otro tema de mi trabajo de Tesis Doctoral ha sido el estudio de la reacción de éteres de enol con alquinos catalizada por platino y por oro. Cuando uno de los átomos del puente entre el alquino y el éter de enol es un oxígeno se obtienen 3-oxabiciclo[4.1.0]hept-4-enos mediante la ciclopropanación intramolecular de éteres de enol por alquinos catalizada por Pt(II) u Au(I) De acuerdo con el esquema general del mecanismo de la ciclación de 1,6-eninos catalizada por Pt(II), Pd(II) y Au(I), los ciclopropil carbenos metálicos formados en la ciclación de tipo 6-endo-dig pueden evolucionar para dar anillos de siete miembros. Este tipo de reactividad ha sido observada por primera vez en la reacción intramolecular que hemos desarrollado de éteres de enol con alquinos catalizada por complejos de oro y platino electrófilos. En algunos ejemplos de las reacciones catalizadas por Au(I) se han obtenido acetales fruto de un complejo reordenamiento de la molécula que también transcurre a través de un intermedio con un anillo de siete miembros.Finalmente, hemos hecho una nueva propuesta para el mecanismo de la ciclación de alquinil iminas para dar pirroles catalizada por Cu(I), corrigiendo el mecanismo originalmente propuesto por Gevorgyan. De acuerdo con la nueva propuesta, hemos hecho un estudio de la síntesis de pirroles sustituidos en posición tres. / Indole is a structure present in a large number of alkaloids and natural products with important pharmaceutically properties. Although a variety of methods have been developed to sythesize derivatives of this heterocycle and to modify its substitution pattern, new methods that provide indole derivatives are still of high interest in organic chemistry. An interesting way to obtain indole derivatives could be the catalytic hydroarylation of alkynes, although this method has not been widespread developed, until now.We have found that the intramolecular hydroarylation of alkynes using recently developed cationic gold(I) complexes allows the synthesis of seven membered ring indole derivatives by a 7-exo-dig cyclization process. Interestingly, AuCl3 promotes the formation of eight membered rings by an unusual 8-endo-dig cyclization. In some cases, we have also observed the formation of allenes or tetracyclic derivatives with gold(I), as a result of a fragmentation reaction. Based on experimental results, a mechanism has been proposed to explain the formation of these compounds. This mechanism involves a C-C bond formation at C-3 followed by a 1,2-migration in a Friedel-Craft type reaction.We have also developed the intermolecular reaction between indoles and alkynes catalyzed by gold, giving rise to a wide range of different products.In the second chapter of this Thesis the methodology developed for the cyclization of indoles with alkynes has been applied to the study of the total synthesis of the family of natural products lundurines A-D. This products contain an indoloazocine unit and by the cyclization of the appropiate substrate the tetracyclic core of the lundurines has been synthetized.Another topic of my Doctoral Thesis is the study of the reaction of enol ethers with alkynes. A methodology for the synthesis of 3-oxa-biciclo[4.1.0]hept-4-enes catalyzed by Pt(II) and Au(I) has been developed The general mechanism of Pt(II)-, Pd(II)-, and Au(I)-catalyzed reactions between alkynes and alkenes has been demonstrated in the context of 1,6-enyne cyclization. Accordingly cyclopropyl metal carbenes formed in the 6-endo-dig cyclization may evolve to form seven-membered ring intermediates. This has been achieved for the first time by using highly electrophilic platinum(II) and gold(I) complexes. Gold(I) also triggers a remarkable rearrangement of certain enynes leading to complex cyclic systems. This reaction also proceeds via a seven-membered ring intermediate.Finally, the mechanism for the cyclization of alkynyl imines catalyzed by Cu(I) to give pyrroles originally proposed by Gevorgyan has been corrected. Based on this new mechanistic proposal, we have carried out a study for the synthesis of 3-substitud pyrroles.
3

Princip znečišťovatel platí v právu životního prostředí / Polluter Pays Principle in environmental law

Kundratová, Eliška January 2021 (has links)
Polluter Pays Principle in environmental law Abstract This diploma thesis deals with the legal principle "polluter pays", which is one of the most important and influential principles of environmental law. The aim was to present a theoretical view of this principle, to point out its meaning, function, development, but also its application in contemporary law, both at the international, European and national levels. The diploma thesis is divided into five chapters. The first chapter deals with the theoretical definition of legal principles, their importance in law in general, with emphasis on the legal principles of environmental law. In the second chapter I introduce and define the basic concepts, which I work with throughout the whole thesis. These concepts are the following terms: "environment", "polluter", "pollution", "environmental damage" and finally "environmental responsibility". The third chapter contains the core of this work - the function and meaning of the "polluter pays" principle, which is mainly the internalization of negative externalities into the polluter's costs. Furthermore, the third chapter describes the application of the principle in selected economic instruments of environmental protection. These are mainly taxes, subsidies, fees, fines and tradable emission permits. The last two...
4

Právní odpovědnost za ekologickou újmu / Liability for ecological harm

Nováková, Alexandra January 2013 (has links)
! This thesis discusses the issue of liability for environmental damages, which includes (i) public-law liability (in Czech legal framework described as "environmental injury") and (ii) private-law liability. The Act on Environmental Damage transposed the Directive on Environmental Liability (the "Directive"), the aim of which is prevention and remedy of environmental damage. The Act on Environmental Damage is legally binding from August 17, 2008, as lex specialis to the Act on Environment and other Acts on respective environmental components. Although the Act on Environmental Damage is based on the public-law approach, the private-law liability remains unaffected. According to the Act on Environmental Damage, the strict liability is imposed on operators of certain high-risk occupational activities and these operators are obliged to implement preventive and remedial measures and bear associated costs. Furthermore, the operators must provide relevant information on the request of competent public authorities.
5

Finanční aspekty právní odpovědnosti za ekologickou újmu / Financial aspects of liability for environmental damage

Cimburková, Iveta January 2014 (has links)
This diploma thesis provides an overview of the aspects connected with financial assurance of liability for environmental damage. First parts of the work define the frame for this topic through its essentials terms and theoretical basis. Also there are introduced the main functions of economic instruments. Part 3 briefly focuses on the ways of codification of liability in the international public law. The main part of this work is dedicated to an adoption of the polluter pays principle to the European Union law and the Czech national law system. Thus parts 4 and 5 describe and evaluate efficiency of this liability system from the perspective of obligation to assure a financial security. Last part gives a list of possible instruments which may be used as a suitable financial security according to the statute n. 167/2008 Sb.
6

Síntesi, caracterització química i estudi de l'activitat biològica de nous complexos de Pt(II) amb lligands de tipus diaminocarboxílic i els respectius ésters i derivats peptídics

Moradell Rabert, Sílvia 13 December 2002 (has links)
El cisplatí, PtCl2(NH3)2, ha estat una de les drogues més utilitzades en la quimioteràpia del càncer des del descobriment de la seva activitat. Però degut a la seva alta toxicitat i greus efectes secundaris, s'han sintetitzat nous compostos amb la finalitat de reduir aquests inconvenients.En aquest sentit, el treball desenvolupat en aquesta tesi doctoral ha estat la síntesi i caracterització de tretze complexos de Pt(II) amb la finalitat d'estudiar llur activitat antitumoral. Aquests complexos presenten unes característiques estructurals comunes: geometria cis, dos lligands làbils de tipus clorur i un lligand diaminoquelatant derivat dels àcids d,l-2,3-diaminopropiònic (Hdap) i d,l-2,4-diaminobutíric (Hdab). S'han dissenyat unes estratègies sintètiques a partir de les quals els lligands han estat funcionalitzats amb diferents grups de tipus éster, aminoàcid i peptídic: Etdap·2HCl, Etdab·2HCl, [(dap-Metala)·2CF3COOH], [(dab-Metala)·2CF3COOH], [(dap-phe)·2CF3COOH], [(dab-phe)·2CF3COOH], [(dap-Mettrp)·2CF3COOH], [(dab-Mettrp)·2CF3COOH], [(dap-ASTTTNYT-NH2)·2CF3COOH], essent Metala= éster metílic de L-alanina, phe= L-fenilalanina, Mettrp= éster metílic del L-triptofà. Aquests lligands diaminoquelatants s'han utilitzat per sintetitzar els corresponents complexos de Pt(II): PtCl2(Hdap), PtCl2(Hdab), PtCl2(Etdap), PtCl2(Etdab), PtCl2(dap-Metala), PtCl2(dab-Metala), PtCl2(dap-ala), PtCl2(dab-ala), PtCl2(dap-phe), PtCl2(dab-phe), PtCl2(dap-Mettrp), PtCl2(dab-Mettrp), PtCl2(dap-ASTTTNYT-NH2).A través de diferents tècniques i assaigs biològics (dicroisme circular, electroforesi en gel d'agarosa, microscopia de forces atòmiques, citometria de flux, assaigs de proliferació cel·lular) s'ha pogut demostrar l'activitat antitumoral d'aquests compostos. A través de la tècnica de dicroisme circular (DC) s'ha pogut demostrar que els lligands lliures no interaccionen covalentment amb el DNA de Calf Thymus i no modifiquen l'estructura secundària de la doble hèlix. En canvi, els respectius complexos han demostrat tenir capacitat per interaccionar amb el DNA i modificar la seva estructura secundària. Els complexos PtCl2(Hdap), PtCl2(Hdab) i PtCl2(dab-phe) mostren un comportament similar al cisplatí, generant adductes cis-bifuncionals que distorcionen la doble hèlix de forma no desnaturalitzant amb obertura de la doble cadena. Els complexos PtCl2(Etdap), PtCl2(Etdab), PtCl2(dap-ala), PtCl2(dab-ala), PtCl2(dap-Metala), PtCl2(dab-Metala), PtCl2(dap-phe), PtCl2(dap-ASTTTNYT-NH2) quan interaccionen amb el DNA generen un canvi en la conformació del DNA de la forma B a la forma C, produint-se un augment de la curvatura de l'hèlix per rotació de les bases nitrogenades. En aquests estudis s'ha comprovat que l'estructura del complex influeix en l'efecte generat sobre l'estructura secundària de l'àcid nucleic. En primer lloc, existeix una diferència en el comportament en funció del tamany del lligand diaminoquelatant, de manera que els complexos amb el lligand (dab) provoquen un efecte més remarcable. També s'observa aquest canvi de comportament al passar dels complexos que tenen el grup funcional esterificat als que el tenen protonat. D'aquesta manera, s'observa un major efecte sobre l'estructura secundària del DNA en aquells complexos que tenen el lligand diaminoquelatant de tres metilens (dab) i amb el grup carboxilat terminal protonat.Per tal de modelitzar la interacció d'aquests complexos amb el DNA, s'ha estudiat la interacció d'aquests compostos de Pt(II) amb 5'-GMP a través de RMN-1H, observant la variació dels senyals corresponents al H8 de 5'-GMP. Així s'ha pogut demostrar que aquests compostos interaccionen amb la 5'-GMP a través d'un enllaç covalent Pt-N7, de la mateixa manera a com interacciona el cisplatí.A través d'electroforesi en gel d'agarosa i microscopia de forces atòmiques (AFM) s'ha pogut determinar l'efecte que generen els lligands lliures i els respectius complexos de Pt(II) sobre l'estructura terciària del plasmidi pBR322. Els lligands provoquen un augment de l'agregació de les molècules de DNA i un lleuger augment de la compactació de l'estructura terciària. Aquests resultats s'atribueixen a la capacitat d'aquests compostos a interaccionar per pont d'hidrogen amb el DNA. Els corresponents complexos de Pt(II) provoquen un augment de l'agregació i una important compactació, degut per una banda a la capacitat de l'àtom de Pt a interaccionar covalentment amb el DNA, i per altra banda, a la capacitat del lligand a interaccionar per pont d'hidrogen amb l'àcid nucleic.Finalment s'ha estudiat l'activitat citotòxica d'aquests complexos de Pt(II) en diferents línies cel·lulars: A431 (línia de carcinoma epidermoide), HeLa (línia de carcinoma de coll d'úter) i HL-60 (línia promielocítica de leucèmia). Els complexos moderadament solubles en aigua, PtCl2(Hdap), PtCl2(Hdab), PtCl2(dap-ala), PtCl2(dab-ala), PtCl2(dap-phe) i PtCl2(dab-phe), han demostrat ser actius. L'activitat depèn de la concentració de complex, del temps d'incubació i de la línia cel·lular. Per temps d'incubació alts i concentracions de complex elevades s'observa la màxima activitat. Els complexos de l'alanina, PtCl2(dap-ala) i PtCl2(dab-ala), són els que mostren més activitat, mentre que els compostos de la fenilalanina són els menys actius, degut probablement a la voluminositat del lligand, la qual pot impedir o dificultar el transport del compost a través de la membrana cel·lular.L'activitat citotòxica dels complexos insolubles en aigua, PtCl2(Etdap) i PtCl2(Etdab), queda bloquejada per l'elevada concentració de DMSO (12%) necessària per solubilitzar els compostos. Aquests resultats permeten deduir que la presència d'un 12% de DMSO anul·la l'activitat d'aquests complexos, ja que el DMSO pot coordinar-se amb el Pt ocupant les posicions làbils del complex i evitant que es pugui coordinar amb el DNA.Els assaigs de proliferació cel·lular del complex PtCl2(dap-ASTTTNYT-NH2) i del pèptid lliure ASTTTNYT-NH2 han demostrat que ambdós compostos són actius. Tot i això, l'activitat del complex és superior a la del pèptid lliure, ja que el Pt pot interaccionar covalentment amb el DNA i augmentar l'efecte citotòxic. Per tant, el complex presenta un lligand portador biològicament actiu que pot transportar el metall a través de la membrana cel·lular i facilitar així la seva interacció amb el DNA.A través de la tècnica de citometria de flux s'ha comprovat que en tots els casos la mort cel·lular produïda pels complexos ha estat per apoptosi.Per últim, s'ha sintetitzat i caracteritzat un complex trinuclear de Pt(II), {[Pt(Me2Bpy)2][PtCl2(Me2Bpy)]2}, essent Me2Bpy= 4,4'-dimetil-2,2'-dipiridil. La resolució de la seva estructura per difracció de Raig-X ha permès determinar l'existència d'una interacció intramolecular Pt-Pt de 3.474 Å. / Cisplatin, PtCl2(NH3)2, has been one of the most used drugs for the cancer chemotherapy. However, due to its high toxicity and important side effects, new complexes have been synthesized in order to reduce these disadvantages.In that way, the work presented in this thesis is the synthesis and characterization of 13 Pt(II) complexes in order to study their antitumor activity. These complexes present some common traits: cis geometry, two labile chloride ligands, and one diamine chelating ligand derived from d,l-2,3-diaminopropionic acid (Hdap) and d,l-2,4-diaminobutyric acid (Hdab). These ligands have been derived using new synthetic strategies with different functional groups as ester, aminoacid and peptide type: Etdap·2HCl, Etdab·2HCl, [(dap-Metala)·2CF3COOH], [(dab-Metala)·2CF3COOH], [(dap-phe)·2CF3COOH], [(dab-phe)·2CF3COOH], [(dap-Mettrp)·2CF3COOH], [(dab-Mettrp)·2CF3COOH], [(dap-ASTTTNYT-NH2)·2CF3COOH], being Metala= methyl ester of L-alanine, phe= L-phenylalanine and Mettrp= methyl ester of L-triptophan. These ligands have been used for preparing the following Pt(II) complexes: PtCl2(Hdap), PtCl2(Hdab), PtCl2(Etdap), PtCl2(Etdab), PtCl2(dap-Metala), PtCl2(dab-Metala), PtCl2(dap-ala), PtCl2(dab-ala), PtCl2(dap-phe), PtCl2(dab-phe), PtCl2(dap-Mettrp), PtCl2(dab-Mettrp), PtCl2(dap-ASTTTNYT-NH2).Using different techniques and biologic assays (circular dichroism, agarose gel electrophoresis, atomic force microscopy, flow cytometry, cell proliferation assays) the antitumor activity of these complexes has been demonstrated.With circular dichroism it has been demonstrated that free ligands do not covalently bind Calf Thymus-DNA and do not modify its secondary structure. In constrast, the corresponding Pt(II) complexes are able to interact with DNA and modify its secondary structure. Complexes PtCl2(Hdap), PtCl2(Hdab) and PtCl2(dab-phe) behave in the same direction as cisplatin, forming cis-bifunctional intrastrand adducts that probably open the double helix. The other complexes, PtCl2(Etdap), PtCl2(Etdab), PtCl2(dap-ala), PtCl2(dab-ala), PtCl2(dap-Metala), PtCl2(dab-Metala), PtCl2(dap-phe), PtCl2(dap-ASTTTNYT-NH2), interact with DNA generating a BC transformation with increasing winding of the double helix by rotation of the bases. The influence of the complex structure in the effect on the secondary structure of DNA has been proved. Firstly, a difference in the behaviour exists depending on the ring size, so complexes with (dab) ligand cause bigger modifications. This kind of behaviour is also seen between complexes with ester groups at the C-terminus and complexes with carboxylic group. Thus, there is a greater effect in the secondary structure of the DNA in those complexes that have the (dab) ligand and a protonated carboxylate group.The interaction between the platinum complexes and 5'-GMP has been studied by 1H-NMR, following the variation of H8 signals from 5'-GMP. It has been demonstrated that all complexes covalently interact with 5'-GMP through the N7 of the base, as cisplatin do.The effect generated by free ligands and their Pt(II) complexes in the tertiary structure of pBR322 DNA has been determined by agarose gel electrophoresis and atomic force microscopy (AFM). Generally, the free ligands studied generate an increase of DNA aggregation and a slight coiling of the double helix, due to their possibility of forming hydrogen bonds with the DNA bases through different functional groups of their structure. The Pt(II) complexes generate an important coiling and aggregation of DNA, probably due to the covalent binding Pt-DNA and hydrogen bond interactions through their ligands.The cytotoxic activity of the Pt(II) complexes has been evaluated through cell proliferation assays in A431, HeLa and HL-60 cell lines using different incubation times (24h, 48h, 72h). The water-soluble complexes, PtCl2(Hdap), PtCl2(Hdab), PtCl2(dap-ala), PtCl2(dab-ala), PtCl2(dap-phe) i PtCl2(dab-phe), show antitumor activity in a dose- and time- dependent manner, gradually decreasing the cell survival percentage when the complex concentration increase, in the same direction as carboplatin. All these complexes present the highest activity at long incubation times and high complex concentration. The alanine complexes, PtCl2(dap-ala) and PtCl2(dab-ala) are the most active and those of phenylalanine are the less active, probably due to the ligand size, which can make its transport through cell membrane more difficult.The water-insoluble complexes, PtCl2(Etdap) and PtCl2(Etdab), apparently do not show antitumor activity due to the presence of 12% DMSO necessary por solving these complexes. In these conditions they do not cause a decrease in cell survival. The DMSO could interact with platinum, displacing the labile ligands of the complex and not allowing it to interact with DNA. Complex PtCl2(dap-ASTTTNYT-NH2) is also insoluble in water, but can be dissolved in 2% DMSO solution. Cell proliferation assays show that the free peptide, ASTTTNYT-NH2, and the platinum complex are both active. The activity of the complex is higher than the free peptide, probably because platinum can covalently interact with DNA and increase the cytotoxic effect. This result suggest that the ligand can act as a carrier ligand and make the interaction metal-DNA be easier.Flow cytometry assays have demonstrated that cell death generated by the complexes synthesized is apoptosis. Agarose gel electrophoresis of extracted DNA show a classical 200-base pair integer oligonucleosome ladder.A new trinuclear Pt(II) complex, {[Pt(Me2Bpy)2][PtCl2(Me2Bpy)]2} being Me2Bpy= 4,4'-dimethyl-2,2'-dipyridyl, has been synthesized and characterized. The X-ray diffraction of its structure shows the existence of an intramolecular Pt-Pt interaction of 3.474 Å.
7

Nápravná opatření v ochraně životního prostředí / The remedial measures in the protection of the environment

Derlich, Stanislav January 2011 (has links)
The remedial measures in the protection of the environment. This thesis focus on the remedial measures which belong to legal instruments and create an integral part of the public law. The public bodies, which are responsible for the enforcement of public interests, are in charge of enforcement of remedial measures to be done. As in the international law, the state is primarily responsible for remedying of damages arising from activities under its jurisdiction. Despite the remedial measures are incorporated into almost all legal enactments, the quality of the legislature is rather low and this legal tool has been beyond the academical interest. The remedial measures represent one of the most important instruments of the environment protection and are closely connected with the principles of the environment protection, i.e. the principle of the sustainable development, the polluter- pays principle, the preventive principle and the principle of the State responsibility. The remedial measures create a part of the measures within the environment protection, which primarily work as subsequent measures and partly as continuous and preventive ones. The remedial measures comprise different kinds of measures, the main goal of which is to remedy changes which are considered to be undesired from the legal and...
8

Síntesi, caracterització i avaluació com a catalitzadors de nous complexos quirals de platí

Duran i Carpintero, Josep 22 July 1999 (has links)
The oxidative addition proved to be a useful method to prepare platinum (II) hydridotiolate by reaction of tetrakis(triphenylphosphine)platinum(0) with aminothiolate and phosphinothiolate ligands like cysteamine, cysteine ethyl and methyl Esther, 2-(diphenylphosphino)ethanetiol and 2-(diphenylphosphino)propanetiol.The complexes are square-planar and the aminothiolate or phosphinothiolate ligands are chelated to platinum (II). The hydrido ligand is trans to the sulfur and the other coordination position is occuped by a triphenylphosphine ligand. The complexes are mononuclear and they show low symmetry. The only symmetry element, the plan is broke if the ligand is branched, obtaining asymmetric complexes C1.If the ligand has electronic or esteric impediments the reaction doesn't run and the starting products are recovered. This was observed with N,N-dimethylcysteamine and penicylamine methyl esther ligands. In the special case of orthoaminotiophenol the hydridotiolate was obtained but the ligand was not chelated.The aminothiolate complexes don't show solution equilibrium. Otherwise, the complexe with 2-(diphenylphosphino)ethanetiol show an isomerisation equilibrium which forms cis isomer as a minor component. The complexe with 2-(diphenylphosphino)-propanetiol shows a conformational equilibrium between chair and twist forms.The complexes have been tested as catalyst precursors in hydroformylation and hydrosilylation reactions.The hydroformylation reaction runs only in presence of SnCl2 as cocatalyst. Catalytic activity depends on the presence of triphenylphosphine and, with less magnitude, CO and H2 pressure. We also studied the enantioselectivity using a chiral complexe.In the hydrosililation reaction, catalysts run with good results (<90%) using triethylsilane as silicon hydride. Dehydrogenative addition product has been also found in this reaction.
9

Zpoplatnění vodní dopravní infrastruktury v EU / Charging of inland waterways in the European Union

Horynová, Dana January 2017 (has links)
Continuous growth in transport performance leads to deterioration of the transport infrastructure and there is also a need for states to raise funds to cover the costs of repairs, maintenance and modernization of this infrastructure. One option is to charge users of such infrastructure. In the Czech Republic there is a system of charges only for the use of road and rail transport routes. There is no charging of waterways in the Czech Republic, but it exists in some european countries. This diploma thesis deals with the issue of the charging of waterways in the European Union and thus points out the existence of an alternative possibility of financing expenditures for repairs, maintenance or modernization of the transport infrastructure serving the Czech water transport. The first three chapters contain the theoretical background, focusing in particular on the importance of freight water transport and European policy. The other chapters include an analysis of the established charging system for waterways in Germany. Subsequently, the total revenue from the charging of users of waterways for freight transport is calculated. From this analysis, the thesis is also based on the creation of a model for charging the Elbe waterway in the Czech Republic. After creating the preconditions for charging the Elbe waterway, the potential revenue obtained by this charging was also calculated and compared with the average annual cost of repairs and maintenance of watercourses in the Czech Republic.

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