02 (1996) Scientific papers, Series A
Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/38112
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Článek Otevřený přístup peer-reviewedpublished Infrared and 13C, 15N and 119Sn NMR spectral study of some tri- and diorganotin(IV) pyridinecarboxylates(Univerzita Pardubice, 1996) Lébl, Tomáš; Holeček, Jaroslav; Lyčka, AntonínEleven organotin(IV) pyridinecarboxylates of general formula R3SnOOCR´ and R2Sn(OOCR´)2 where R is 1-butyl or phenyl and R´ is 2-, 3- or 4- pyridyl were prepared. Structures of these compounds in the solid state and in solutions of non-coordinating solvent (CDCl3) and coordinating solvent ((CD3)2SO) were studied using IR spectroscopy, multinuclear (13C, 15N, 119Sn) NMR spectroscopy and 119Sn CP MAS spectroscopy.Článek Otevřený přístup peer-reviewedpublished N-butyltin perchlorates and methanesulfonates, their complexes with pyridine and 2,2´ bipyridine(Univerzita Pardubice, 1996) Hollein, Martin; Handlíř, KarelTri-n-butyltin(IV) and di-n-butyltin(IV) methanesulfonates and perchlorates were prepared and reacted with pyridine (py) and 2,2´-bipyridine (bipy). The complexes are formed by dibutyltin bis(methanesulfonate) with bipy (1:1), tributyltin perchlorate with py or bipy (both 1:1), and dibutyltin bis(perchlorate) with py or bipy (both 1:2). The compounds prepared were studied by multinuclear NMR spectroscopy and IR spectroscopy. The reaction of bis(tributyltin) oxide with aqueous solution of perchloric acid is mentioned as well.Článek Otevřený přístup peer-reviewedpublished 13C and 119Sn NMR spectra of some monophenyltin(IV) compounds(Univerzita Pardubice, 1996) Pejchal, Vladimír; Holeček, Jaroslav; Lyčka, AntonínThe 13C and 119Sn NMR spectra of some monophenyltin(IV) compounds in solution of non-coordinating (CDCl3) and coordinating ((CD3)2SO) solvents have been studied. From the values of δ(119Sn), 1J(119Sn, 13C) and additional 13C NMR parameters the coordination numbers of the central tin atom and the shapes of coordination polyhedra around the tin atom have been evaluated.Článek Otevřený přístup peer-reviewedpublished Formation of some heterocycles based on hydrogen cyanide(Univerzita Pardubice, 1996) Sedlák, Miloš; Kaválek, Jaromír; Macháček, Vladimír; Štěrba, VojeslavCyanogen chloride (prepared from hydrogen cyanide) has been used to prepare chlorosulfonyl isocyanate which cab be adopted as the starting material in syntheses of N-methyl-N-phenyl-sulfuric diamides whose ortho derivates are cyclized to give substituted (1H)-2,1,3-benzothiadiazin-4(3H)-one-2,2-dioxides. Nucleophilic substitution of cyanogen chloride with sodium benzenesulfinate produces benzenesulfonyl cyanide – the starting material for production of substituted 1,2,4-oxadiazoles. Hydrogen cyanide itself was used in the Strecker synthesis of aminonitriles which served for preparation of substituted imidazolines. The nucleophilic substitution of benzoyl chloride and potassium thiocyanide gave benzoyl isothiocyanate which was further transformed into derivates of substituted 2-thioxo-4-quinazolones.Článek Otevřený přístup peer-reviewedpublished Formation of carbonate or benzoate esters via nitrosocarbonyl compounds(Univerzita Pardubice, 1996) Mindl, JaromírA novel on-vessel oxidation and subsequent solvolysis of hydroxamic acids in the presence of lead(IV) oxide have been explored.Článek Otevřený přístup peer-reviewedpublished The testing of atomic absorption sources(Univerzita Pardubice, 1996) Pospíšilová, Radka; Černohorský, TomášThe study was undertaken to compare the light sources of atomic absorption spectrometry for flame and furnace analysis. The hollow cathode lamps and boosted discharge lamps for determination of Se, As, Cd and Pb were tested. The main analytical characteristics as baseline noise, sensitivity, detection limits and linearity of calibration curves were measured. The significant gains in measurements of noise, sensitivity and linearity of calibration for Cd and Pb for discharge boosted lamps were observed.Článek Otevřený přístup peer-reviewedpublished Terminal velocity of spherical particles falling through non-Newtonian suspensions(Univerzita Pardubice, 1996) Machač, Ivan; Ulbrichová, Iva; Elson, Tim P.; Cheesman, David J.The terminal falling velocities of glass, steel, and lead spheres in shear-thinning suspensions of kaolin and titanium dioxide in water solutions of glycerol have been measured. Overall, 130 spherical particle – suspension combinations gave been tested giving a Reynolds number range of 0.001 < Retn < 452. The suitability of the correlations presented for the prediction of the drag coefficient of spheres falling through power-law and Herschel–Bulkley model fluids, has been evaluated by comparing their predictions with the above-mentioned experimental data.Článek Otevřený přístup peer-reviewedpublished Steady-state permeate flux of crossflow ceramic microfiltration(Univerzita Pardubice, 1996) Mikulášek, PetrThis paper deals with both theoretical and experimental studies of the ceramic microfiltration of dilute model suspensions. Steady-state permeate fluxes were analyzed and a simple model based on the critical flow velocity theory has been developed and tested in this study. This model predicts satisfactory the steady-state permeate flux of crossflow microfiltration under various operating conditions.Článek Otevřený přístup peer-reviewedpublished Integrated environment for simulation of chemical reaction kinetics(Univerzita Pardubice, 1996) Němcová, Andrea; Plocek, Jiří; Dlask, VladimírThis article briefly describes an investigated environment suitable for simulation of the kinetics of the chemical reactions. The term “simulation model“ is presented in the article together with the well-known terms such as “reaction scheme” and “mathematical model”. The simulation model is suitable for solving the problems of reaction kinetics. Integrated environment can be used for simulation of biological processes and activated-sludge basins for the biological waste-water treatment.Článek Otevřený přístup peer-reviewedpublished Tetragonal layered compounds with vanadyl phosphate structure and their intercalation reactions(Univerzita Pardubice, 1996) Beneš, Ludvík; Zima, VítězslavIntercalation reactions of vanadyl phosphate, niobyl phosphate, vanadyl arsenate, and vanadyl sulphate are summarized. In the review, the intercalations of molecular guests (water, alcohols, amines, carboxylic acids, amides, heterocycles, and metallocenes) and ions (alkali metals, divalent metals, and alkylammonium ions) are described. Layered compounds derived from vanadyl phosphate dihydrate, in which a part of vanadyl group is replaced by trivalent metal (Al, Cr, Fe, Ga, Mn), are mentioned.