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91.
E. Havránek A. Bumbálová J. Čižmárik 《Journal of Radioanalytical and Nuclear Chemistry》1984,85(1):21-31
The applicability of two nuclear analytical methods for the determination of hepatacaine hydrochloride in solution was studied, i. e. radionuclide X-ray fluorescence analysis and radiometric titrations based on precipitate formations. Methods used were evaluated on the basis of obtained sensitivity values. 相似文献
92.
P. Vaňura V. Jedináková-Křížová M. Vobecký 《Journal of Radioanalytical and Nuclear Chemistry》2006,267(2):501-503
Summary An extraction technique for the separation of 90Sr from a high excess of90Y has been developed. This procedure can be used for the determination of trace amounts of90Sr in90Y prepared by a radiochemical90Y/90Sr generator by liquid scintillation. 相似文献
93.
P. Vaňura V. Jedináková-Křížová A. Yoshioka 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(3):511-514
Extraction of strontium and yttrium by the nitrobenzene solution of H+-form of heptachloro-bis-1,2-dicarbollylcobaltate (H+B–) in the presence of benzo-15-crown-5 (B15C5, L) has been investigated. The presence of B15C5 leads to a great synergistic effect for the extraction of strontium and an antagonistic effect for the extraction of yttrium. The extraction constants of Sr2+ complexes of B15C5 were determined. The separation factor a(Sr/Y) in the system with B15C5 presents the same order of magnitude as that for 15C5. 相似文献
94.
The infrared spectra of mixtures of syn and anti acetaldoxime and its deuterated analogues CH3CHNOD, CD3CHNOH, CD3CDNOH and CH3CDNOH have been recorded. The syn and anti isomers of CH3CHNOH, CD3CHNOH, CD3CDNOH and CH3CDNOH have been separated by gas chromatography [1]. The infrared spectra of separated isomers in CS2 solution have been recorded and the assignment of ten in-plane vibrations made. From a normal coordinate analysis the Urey-Bradley force field, the potential energy distribution and additional information about assignments have been obtained.For the anti isomer the simple Urey-Bradley force field gives satisfactory agreement between the calculated and measured frequencies. For the syn isomer it is necessary to take into account the interactions between atoms separated by three bonds. 相似文献
95.
Zusammenfassung Die bei 1850, 2000 bzw. 2300°C durch die Reduktion von Scandiumoxid mittels Kohlenstoff in dem der Scandiumdicarbidbildung entsprechenden Molverhältnis hergestellten Produkte wurden mit Wasser zersetzt und mit Hilfe der gleichzeitigen gaschromatographischen und massenspektrometrischen Analyse untersucht. Aus den Ergebnissen geht hervor, daß bei der Scandiumdicarbidbildung gleichzeitig ein weiteres Scandiumcarbid, höchstwahrscheinlich ein Sesquicarbid, entsteht.
Herrn Prof. Dr.H. Nowotny gewidmet.
7. Mitt.: Coll. Czech. Chem. Commun., im Druck. 相似文献
Scandium(III) dicarbide problem. Further experimental results
Products obtained by the reduction of Sc2O3 with carbon at 1850, 2000 and 2300°C, resp., in the molar ratio corresponding to the scandium dicarbide were hydrolysed with water. Gaseous reaction products were analysed using gas chromatography combined with mass spectrometry. Results show, that during dicarbide formation another scandium carbide, probably sesquicarbide, is also formed.
Herrn Prof. Dr.H. Nowotny gewidmet.
7. Mitt.: Coll. Czech. Chem. Commun., im Druck. 相似文献
96.
Dušan J. Radanović Zoran D. Matović Gustavo Ponticelli Paola Scano Inessa A. Efimenko 《Transition Metal Chemistry》1994,19(6):646-650
Summary The synthesis and characterization of AuIII complexes with several heterocyclic ligands are reported. The compounds have general formula [AuX3(L)], where L =N-methylimidazole (N-MeIz),N-ethylimidazole (N-EtIz),N-propylimidazole (N-PrIz), benzoxazole (BO), 2-methylbenzoxazole (2-MeBO), 2,5-dimethylbenzoxazole (2,5-diMeBO), 2-amino-pyrimidine (2-APm), 4(6) -hydroxy-pyrimidine [4(6)-hydrPm] or hypoxanthine (Hypox) and X = Cl or Br. Elemental analysis, conductivity measurements and spectral studies were used for the characterization of the complexes. A square-planar geometry withN-bonded heterocyclic ligands is suggested. 相似文献
97.
Štefan Marchalín Dušan Ilavský Milan Bruncko 《Monatshefte für Chemie / Chemical Monthly》1989,120(12):1101-1105
Summary Good yields of substituted 5-(5R-2-furyl)-4H-pyrano[2,3-d]pyrimidines4 were obtained in the reaction of 2-ethoxymethyleneamino-3-cyano-4H-pyranes2 with ammonia. Compounds2 were prepared by the condensation of the starting 2-amino-5-acetyl-3-cyano-6-methyl-4H-pyranes1 with ethyl orthoformate. Spectral properties of the bicyclic system4 in relation to compounds3 are discussed. 相似文献
98.
Feng Zhao Yu-Kou Du Ping Yang Ji’an Tang Xing-Chang Li 《Colloid and polymer science》2005,283(12):1361-1365
In the present study, the structure and morphology of single sodium poly(styrenesulfonate) (PSS) molecules adsorbed to mica
surface from the natural aqueous solution is investigated using atomic force microscopy technique. Results show that single
PSS molecules are observed which show a morphology of wormlike coils. Meanwhile, single sodium poly(styrenesulfonate) (PSS)/Hexadecyltrimethylammonium
bromide (CTAB) complexes deposited on mica from the air–water interface are also observed. However, the PSS/CTA+ complexes show different conformations by appearing in the morphology of circular patches. Experimental data are in fair
agreement with the theoretical analysis. 相似文献
99.
Zusammenfassung Es wurden Fällungssysteme Silbernitrat-Alkaliphosphat und Silbernitrat-Alkaliphosphat-Kaliumbromid tyndallometrisch untersucht, wobei festgestellt wurde, daß sich in dem Fällungssystem AgNO3-Na3PO4 zwei Maxima bilden: das Silberoxyd- und das Silberphosphat-Maximum, während beim Zusatz von KBr noch ein weiteres Silberbromid-Maximum entsteht. Der Einfluß zugesetzter Salpetersäure wurde systematisch geprüft und die betreffenden pH-Werte mittels der Glaselektrode bestimmt. Das Silberphosphat-Maximum wird immer bei ungefähr demselben pH-Wert gebildet. In der Diskussion ist der Charakter der Maxima besprochen. Unter Anwendung kleiner Mengen von Gelatine konnte festgestellt werden, daß das Silberphosphat-Maximum ein Kristallisationsmaximum, während das Silberbromid ein Koagulationsmaximum ist. 相似文献
100.
The absorption spectra of Co(II) chloride complexes, containing variable concentrations of chloride ligand, in a molten mixture of 80 mol% acetamide–20 mol% calcium nitrate tetrahydrate, were studied at 313, 333, 353, and 363 K, in the wavelength range 400-800 nm. The melt contains three possible ligands (CH3CONH2, H2O, and NO3
-) for competition with added chloride ligand. Addition of chloride caused a shift of the absorption maximum of octahedral cobalt(II) nitrate towards lower energies and pronounced changes in the shape of the initial spectrum of cobalt(II) nitrate. The effect of temperature changes on the molar absorption coefficient of the Co(II) species was dependent on the chloride concentration and was attributed to the structural changes occurring in the cobalt(II) species. The STAR and STAR FA programs were applied to identify the complex ionic species and to calculate the stability constants of Co(II) complexes formed in this solvent. The results indicate the highest probability of formation of the following complex species: Co(NO3)4
2-, Co(NO3)2Cl2
2-, and CoCl4
2-. Stability constants of each complex were presented for the equilibria occurring at 313, 333, 353, and 363 K. Distribution of the Co(II) species was also calculated over the ranges of chloride concentration and temperature investigated. 相似文献