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121.
Zusammenfassung Die Reaktion von 2-Nitroso-1-naphthol mit Resorcin bzw. Orcin in Äther bei Anwesenheit von HNO3 liefert Benzo[c]phenoxazon-(9) (I), Benzo[c]phenoxazon-(9)-12-oxid (II), Methyl-benzo[c]phenoxazon-(9) (III) sowie 11-Methyl-benzo[c]phenoxazon-(9)-12-oxid (IV). Die Struktur der isolierten Substanzen wurde durch Reduktion mittels TiCl3 sowie durch die UV- und IR-Spektren gestützt.
Mit 1 Abbildung 相似文献
The reaction of 2-nitroso-1-naphthol with resorcinol and orcinol in ether solution in the presence of nitric acid has been studied. From the reaction mixture the benzophenoxazones I–IV have been isolated. Structures were assigned on the grounds of UV and IR spectra and partly by using TiCl3 as a reducing agent.
Mit 1 Abbildung 相似文献
122.
Influence of Coriolis coupling on excitation of some Nilsson states in155Gd,157Gd and167Er by inelastic scattering of 12·1 MeV deuterons is analysed. Expanded Nilsson potential with hexadecapolar deformation is used for the model calculations. Theoretical values of reduced transition probability,B(E2) are compared with experimental ones. 相似文献
123.
J. Adam A. Kuklík A. Špalek D. Venos M. Ja. Kuznecova 《Czechoslovak Journal of Physics》1978,28(8):857-864
Gamma-radiation from the reactions of 28 MeV and 26 MeV3He-ions on the209Bi target has been studied by means of Ge(Li) detectors. Individual observed prompt -ray transitions have been assigned to the corresponding reactions. The results of previous studies of the209At nucleus have been verified and completed. Two new levels at energies of 640 keV and 1270·5 keV have been introduced. Additionally, 15 new transitions have been observed which could belong to209At. The209At level structure is discussed in terms of nuclear models. 相似文献
124.
The influence of different modes of preparation on the stoichiometry of thermal decomposition of isothiocyanatonickel(II) complexes with ammonia was studied. It was found that the complex Ni(NCS)2(NH3)4 (I) prepared by heterogeneous reaction undergoes decomposition in two steps (–2 NH3, –2 NH3), while for complex II, of the same composition but prepared by homogeneous reaction from solution, the decomposition proceeds in three steps (–1 NH3, –1 NH3, –2NH3). Electronic and infrared absorption spectra were used for the study of the spectral properties of the starting complex. It was found that the different stoichiometries of thermal decompositions of complexes I and II do not cause differences in the bonding strength of the ammonia molecules (chemical factor); this effect is rather brought about by physical factors such as different imperfections of the crystal lattice.
Zusammenfassung Der Einfluß der Herstellung auf die Stöchiometrie der thermischen Zersetzung von Amin-Komplexen des Isothiocyanatonickels wurde studiert. Der Zerfall des Komplexes Ni(NCS)2(NH3)4 (I), hergestellt durch heterogene Reaktion, verlief in zwei Etappen (–2 NH3, –2 NH3). Beim selben Komplex (II), hergestellt durch homogene Reaktion in Lösung, wurden jedoch drei Etappen beobachtet (–1 NH3, –1 NH3, –2 NH3). Die Eigenschaften des Ausgangsproduktes wurden durch Elektronen- und IR-Spektroskopie untersucht. Das unterschiedliche thermische Verhalten ist nicht auf eine verschiedene Bindungsstärke der NH3 Moleküle, sondern auf physikalische Ursachen, wie z. B. Unregelmässigkeiten im Kristallgitter zurückzuführen.
Résumé On a étudié l'influence des diverses méthodes de préparation sur la stoechiométrie de la réaction de décomposition thermique des complexes de l'isothiocyanate de nickel(II) avec l'ammoniac. On a établi que le complexe Ni(SCN)2(NH3)4, (I), préparé rar réaction hétérogène, subit une décomposition en deux étapes (–2NH3, –2NH3), tandis que le complexe (II), de même composition, mais préparé par réaction homogène, à partir de solutions, se décompose en trois étapes (–1NH3,–1NH3, –2NH3). Les propriétés spectrales du complexe initial ont été étudiées par absorption électronique et infrarouge. On a trouvé que les différences de stoechiométrie des réactions de décomposition thermique des complexes (I) et (II) n'apportaient pas de différences entre les énergies de liaison des molécules d'ammoniac (facteur chimique). C'est plutôt à des facteurs physiques, comme les différentes imperfections du réseau cristallin, que cet effet serait dû.
(II) . , Ni(NCS)2(NH3)4 (I), , (–2NH3,–2NH3). , II , , (–1 NH3,–1 NH3 –2NH3). . , I II ( ), , .相似文献
125.
A universal and fast method of90Sr determination in environmental matrices (raw and dried milk, plants, soils) has been elaborated. Solvent extraction method of daughter90Y by tributyl phosphate was used. The method of strontium determination is compatible with determination of other transuranic elements (americium, plutonium) and there is no need to check the chemical yield of strontium. 相似文献
126.
A procedure is described for the determination of the total concentration of organophosphorus pesticides in aqueous solution based on conversion of the compounds to orthophosphoric acid by oxygen-flask combustion and spectrophotometric determination as phosphomolybdenum blue. The procedure is particularly sensitive when preceded by efficient and selective accumulation of pesticides. The adsorption of malathion, parathion and phosalone on Amberlite XAD-4 resin from 1 l of 7–36 μM water solutions, followed by combustion of 500 μl of eluate yields of orthophosphoric acid with 90–105% recoveries. The detection limit is ca. 150 ng ml?1 pesticide in an aqueous sample. Inorganic phosphates and most of some commonly present non-pesticide phosphorus compounds are eliminated from the water sample during the adsorption step. In combination with a test for monitoring traces of cholinesterase inhibitors in surface waters, the determination of the total amount of organophosphorus pesticides as a cumulative parameter offers reliable information on the pollution level of the water environment. Application of such a combined procedure to a pond water from an apple orchard showed good correlation between phosphrus content and the cholinesterase inhibition. 相似文献
127.
Daniela Walterová Zdeně;K Stránský Vladimír Preininger Prof. Dr. Vilím Šimánek 《Electrophoresis》1985,6(3):128-132
The isotachophoretic behavior of quaternary benzo/c/phenanthridine, protoberberine and aporphine alkaloids in different electrolyte systems is described. The concentration of the leading ion and the pH value of the leading electrolyte affect the relative effective mobilities of the alkaloids. The system of pH 4.7, containing the leading ion K+ (0.005 M) counter ion acetate, and the terminating ion β-alanine (0.02 M), has been selected for the quantitative determination of the studied alkaloids in model mixtures and plant extracts. 相似文献
128.
Herein, we report the first use of chiral alkaloid brucine to synthesize novel porphyrin-brucine conjugate capable of acting as a gelator of methanol and acetonitrile at extremely low level of concentration. The synthesis, characterization and spectral properties of gelator based on a novel structural motif, quaternized alkaloid conjugates, are described. Different spectroscopic methods (1H NMR spectroscopy, Raman and infrared spectroscopy, and spectroscopy of electronic and vibrational circular dichroism) were used for characterization of the prepared organogel. The aggregation of the gelator studied by UV-vis spectroscopy and electronic circular dichroism showed the formation of chiral J-aggregates in water and water-methanol (1:1) mixture. A new methodology for the determination of functional groups involved in gel formation based on vibrational circular dichroism is presented. 相似文献
129.
J. Krištiak O. Šauša P. Bandžuch J. Bartoš 《Journal of Radioanalytical and Nuclear Chemistry》1996,210(2):563-570
The temperature dependence of positron annihilation characteristics,
3 andI
3, has been studied on sample of poly(butadiene), poly(isobutylene) and poly(chloroprene). The temperature range was between 15 and 470 K. The rate of expansion of holes or free-volume in all samples was deduced belowT
g as well aboveT
g as appr. 3·10–3 K–1 and 2·10–2 K–1, respectively. These values are very close to the rate of the mean squared displacement of scatterer<r
2>observed in neutron scattering experiments. A possibility to use an inverse value of free-volume,V
f
–1
for study of viscoelastic state of polymers is demonstrated. 相似文献
130.
Z. Šimša V. Roskovec F. Zounová P. Novotný W. Keilig 《Czechoslovak Journal of Physics》1977,27(1):88-98
An extended version of the noncollinear spin model bySawatzky et al. is developed to derive a dependence of the differential high field susceptibility on the degree of inversion of the ferrite MnFe2O4. Using the available data on the main molecular field coefficients it is shown that the present model imposes restrictions on values of. Determination of from the measurements of the field dependence of the saturated moments at low temperatures on samples with varying degrees of inversion reveals good quantitative agreement with the present model. 相似文献