National Repository of Grey Literature 38 records found  beginprevious21 - 30next  jump to record: Search took 0.01 seconds. 
Geminal bis(phosphinates)
David, Tomáš ; Lukeš, Ivan (advisor) ; Grüner, Bohumír (referee) ; Růžička, Aleš (referee)
Slow complexation is one of the major limitations of current macrocyclic chela- tors utilized in nuclear medicine for complexation of metal radionuclides. This property can be improved by ligand design. Among metal radioisotopes, the copper ones (e.g. 60Cu, 61Cu, 62Cu, 64Cu and 67Cu) have become commonly available in recent years and cyclam-derived ligands are the most suitable ligands for Cu2+ complexation. To alter the complexation rate, bis(phosphinic acid) group is promising unit as it is able to complex metal ions in acidic solu- tions. However, geminal bis(phosphinates) represent poorly studied group of compounds and, thus, it is challenging to uncover their properties. Several simple amino-bis(phosphinates) were synthesized and its acid-base and coordi- nation properties were studied. Unlike structurally similar geminal bis(phosphonates), the title compounds showed negligible adsorption onto hydroxyapatite (commonly used model of bone tissue). The obtained knowledge dealing with geminal bis(phosphinates) was utilized in synthe- sis of two novel cyclam derivatives. The ligands (bearing either one geminal bis(phosphinate) or one geminal phosphino-phosphonate pendant arm) were synthesized by highly efficient procedure. The corresponding Cu2+ complexes are formed with very high rates and show...
Study of transport properties of some polymer layers
Růžička, Aleš
This work studies various properties of polymer layers and hybrid layers containing inorganic nanoparticles. MEH-PPV and Polythiophene films are characterized by different experimental techniques. Dark J-V characteristics were measured at different temperatures and the mobility of holes was evaluated in a few cases. Photovoltage spectra are used for a determination of the exciton diffusion length and the SPV method is discussed. The influence of the inorganic nanoparticles CdS and ZnO incorporated into the polymer layers is studied by various experimental methods and the applications of these layers in the inorganic-organic hybrid solar cells are discussed. The inorganic nanoparticle size distributions are obtained by several experimental techniques and the results correspond with the assumptions.
Synthesis and Use of Transition Metal Complexes with Helical Ligands
Žádný, Jaroslav ; Vojtíšek, Pavel (advisor) ; Kotora, Martin (referee) ; Růžička, Aleš (referee)
The Thesis describes our successful endeavour to develop asymmetric synthesis of functionalized 2H-pyran or 2,7-dihydrooxepine helicene-like compounds in an optically pure form. These helicene surrogates were fully characterized and their use in enantioselective catalysis as chiral ligands, organocatalysts or chiral modifiers was explored. A general method for the preparation of optically pure [5]- and [6]heterohelicenes by asymmetric synthesis is based on highly diastereoselective [2+2+2] cycloisomerization of centrally chiral triynes mediated/catalyzed by transition metal complexes. Stereochemical outcome of the cyclization process is controlled by 1,3-allylic-type strain. This new methodology is highly versatile providing an easy access to chiral ligands, organocatalysts or modifiers in a nonracemic form. Optically pure 2,7-dihydrooxepine [5]helicene-like phosphite ligands were explored in enantioselective allylic amination under catalysis by iridium(I) complexes to reach up to 82% ee. An organocatalysts represented by the optically pure 2H-pyran [5]helicene-like DMAP analogue was synthesized and applied to kinetic resolution of racemic sulfoximines. Finally, various functionalized derivatives of helicenes and helicene-like compounds (azahelicenes, DMAP analogues, (thio)urea derivatives) were...
Studium transportních vlastností některých polymerních vrstev
Růžička, Aleš ; Toušková, Jana (advisor) ; Pfleger, Jiří (referee)
This work studies various properties of polymer layers and hybrid layers containing inorganic nanoparticles. MEH-PPV and Polythiophene films are characterized by different experimental techniques. Dark J-V characteristics were measured at different temperatures and the mobility of holes was evaluated in a few cases. Photovoltage spectra are used for a determination of the exciton diffusion length and the SPV method is discussed. The influence of the inorganic nanoparticles CdS and ZnO incorporated into the polymer layers is studied by various experimental methods and the applications of these layers in the inorganic-organic hybrid solar cells are discussed. The inorganic nanoparticle size distributions are obtained by several experimental techniques and the results correspond with the assumptions.
Polar ferrocene amidophosphines for catalytic applications
Schulz, Jiří ; Štěpnička, Petr (advisor) ; Růžička, Aleš (referee) ; Čermák, Jan (referee)
5 Abstract The formerly reported hydroxyamide Ph2PfcC(O)NHCH2CH2OH 1 and its respective novel congeneric analogues Ph2PfcC(O)NHCH3−n(CH2OH)n (3: n = 2; 4: n = 3) were used to prepare a series of arene-ruthenium(II) complexes [(η6 -arene)RuCl2(L-κP)] 6-8 (arene = C6H6, p-cymene, C6Me6; L = 1, 3 or 4). These complexes were studied as pre-catalysts in redox isomerization of allylic alcohols to carbonyl compounds. Among the compounds prepared, complex 6b [(η6 -p-cymene)RuCl2(1-κP)] showed best results. The solid state structure of the product of photolytic decomposition of complex [(η6 - C6Me6)RuCl2(2-κP)] (2 = Ph2PfcC(O)N(CH2CH2OH)2), viz, [(µ-Cl)3{Ru(η6 -C6Me6)}2] [FeCl4] 9, was determined by single-crystal X-ray diffraction analysis. The bis-phosphane complexes [MII Cl2(1-κP)2] (M = trans-Pd (10), cis-Pt (11) and trans- Pt (12)) together with chalcogenide derivatives Ph2P(O)fcC(O)NH(CH2)2OH (13) and Ph2P(S)fcC(O)NH(CH2)2OH (14) derived from hydroxyamide 1 were tested in vitro for their cytotoxicity against human ovarian A2780 cancer cell line. Complexes tested showed moderate cytotoxicity. Triol-amide FcC(O)NHC(CH2OH)3 15 (Fc = ferrocenyl) reacted with decavanadate (Bu4N)2[H3V10O28] at elevated temperature and prolonged reaction time yielding the hybrid hexavanadate (Bu4N)2[{FcC(O)NHC(CH2O)3}2V6O13] 16...
Phosphinoferrocene conjugates of selected amino acids
Tauchman, Jiří ; Štěpnička, Petr (advisor) ; Růžička, Aleš (referee) ; Dvořák, Dalimil (referee)
A series of chiral phosphinoferrocene amides was prepared by the condensation either of 1'- (diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) or its planar-chiral 1,2-isomers and amino acid methyl esters in the presence of peptide coupling agents. The resulting phosphinoamides were tested as ligands in Cu-catalyzed asymmetric conjugate additions of diethylzinc to chalcones and in Pd-mediated asymmetric allylic substitution reactions of 1,3- diphenylallyl acetate with the respective nucleophile (alkylation, amination and etherification). The catalytic tests were focused on an optimization of the reaction parameters (solvent, temperature, base, metal/ligand ratio) and on survey of various substrates. Compounds based on Hdpf proved to be better ligands in both catalytic reactions than their planar chiral analogues. In order to rationalize the influence of the ligand structure on the reaction course and also to interpret the catalytic results, several model complexes were prepared and structurally characterized. Other three series of non-chiral complexes were prepared from the corresponding (η6 - arene)ruthenium(II) precursor and Hdpf-glycine conjugates; the neutral complexes of the type [(arene)RuCl2(Hdpf-Gly(R)-κP)] (arene = benzene, p-cymene, hexamethyl-benzene; R = OMe, NH2, OH) as well as two...
Study of various materials for solar cells-
Růžička, Aleš ; Toušková, Jana (advisor) ; Prokeš, Jan (referee)
Sluneční články jsou slibnou a rozvíjející se alternativou ke klasickým zdroj·m elektrické energie. V této práci studujeme r·zné parametry křemíkových a organických slunečních článk·. Ze získa- ných temných voltampérových charakteristik křemíkového článku naměřených při více teplotách byl určen mechanismus transportu náboje v porovnání s teoretickými modely. Taktéž u organické vrstvy polymeru P3CT byl z temné voltampérové charakteristiky za pokojové teploty navržen me- chanismus transportu náboje. Pro měření voltampérových charakteristik slunečních článk· za osvětlení byl použit simulátor slunečního záření. Z naměřených osvětlených voltampérových charakteristik byly určeny výstupní parametry křemíkových a organických slunečních článk·, přičemž byl kladen d·raz na účinnost přeměny sluneční energie na energii elektrickou. Zjištěná účinnost křemíkového článku byla η = 13, 21% a maximální účinnost organických článk· byla η = 1, 51%.
Slupkové galaxie a modifikovaná Newtonova dynamika
Bílek, Michal ; Jungwiert, Bruno (advisor) ; Růžička, Adam (referee)
Our work has two recherchive parts. The first is devoted to the shell galaxies and we describe the observational facts here, different models of origin and the possibility of determining the gravitational potential with the use of shells. The second part is on the modified Newtonian dynamics (MOND). We explain what it consists in, its implications and its experimental tests. The third part is devoted to our numerical simulations of a shell system evolution both in the classical and modified dynamics. Our mission is to explain the differences in the two simulation theoretically and to verify, whether the result of the modified simulation oppose the observed shells around the galaxy NGC 3923. The conclusion is it doesn't, but our test is not very strong.
Chiral Ferrocene Phosphanyl-carboxylic Ligands
Lamač, Martin ; Štěpnička, Petr (advisor) ; Dvořák, Dalimil (referee) ; Růžička, Aleš (referee)
CharlesUniversityinPrague FacultyofScience,DepartmentofInorganicChemistry - UniverzitaKarlovavPraze Přírodovědeckáfakulta,Katedraanorganickéchemie MartinLamač ChiralFerrocenePhosphanyl-carboxylicLigands - Chirálníferrocenovéfosfanyl-karboxylovéligandy Ph.D.Thesis/Dizertačnípráce Praha2008 2 Contents/Obsah: Summary(English)3 Shrnutí(Česky)13 Publishedarticles/manuscriptsincludedinthethesis23 Listofpublicationsoftheauthorinimpactedjournals26 26 Listofpublicationsoftheauthorinimpactedjournals: 1)P.Štěpnička,M.Lamač,I.CísařováPolyhedron2004,23,921. 2)M.Lamač,I.Císařová,P.ŠtěpničkaJ.Organomet.Chem.2005,690,4285. 3)M.Lamač,P.ŠtěpničkaInorg.Chem.Commun.2006,9,319. 4)M.Lamač,I.Císařová,P.ŠtěpničkaEur.J.Inorg.Chem.2007,2274. 5)J.Kühnert,M.Lamač,T.Rüffer,B.Walfort,P.Štěpnička,H.LangJ.Organomet. Chem.2007,692,4303. 6)M.Lamač,I.Císařová,P.ŠtěpničkaCollect.Czech.Chem.Commun.2007,72,985. 7)M.Lamač,J.Tauchman,I.Císařová,P.ŠtěpničkaOrganometallics2007,26,5042. 8)P.Štěpnička,M.Lamač,I.CísařováJ.Organomet.Chem.2008,693,446. 9)C.Bianchini,A.Meli,W.Oberhauser,A.M.Segarra,E.Passaglia,M.Lamač,P. ŠtěpničkaEur.J.Inorg.Chem.,2008,441. 10)J.Kühnert,M.Lamač,J.Demel,A.Nicolai,H.Lang,P.ŠtěpničkaJ.Mol.Catal.A: Chem.2008,285,41. 11)J.Kühnert,I.Císařová,M.Lamač,P.ŠtěpničkaDaltonTrans.2008,2454....

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