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61.
In acetate buffer medium palladium(II) ions form with promazine hydrochloride (PM) two complexes: an orange one of a formula [Pd(C17H20N2S)]2+ (λmax = 460 nm, ε = 4.5 × 103, at 20 °C and pH = 2) and a violet one of a formula [Pd(C17H20N2S)2]2+ (λmax = 540 nm, ε = 8.8 × 103 at 20 °C and pH = 2).The values for instability constants determined by Bjerrum's method amount to pK1 = 3.95; pK2 = 3.07; pβ1 = 3.95; pβ2 = 7.02, respectively.A colorimetric method of the determination of palladium(II) has been elaborated. The method consists in a measurement of the absorbance of the violet complex of palladium(II) with promazine hydrochloride at λ = 540 nm. The method permits the determination of 2–17 μg Pd/ml with an error of ±2%. The time of the determination is 20 min. Iron(III), Ce(IV), Pt(IV), V(V), Cr(VI), and HNO3 interfere with the determination. 相似文献
62.
al-Khalili A Thomas R Ehlerding A Hellberg F Geppert WD Zhaunerchyk V af Ugglas M Larsson M Uggerud E Vedde J Adlhart C Semaniak J Kamińska M Zubarev RA Kjeldsen F Andersson PU Osterdahl F Bednarska VA Paál A 《The Journal of chemical physics》2004,121(12):5700-5708
Dimethyl disulfide (DMDS) and N-methylacetamide are two first choice model systems that represent the disulfide bridge bonding and the peptide bonding in proteins. These molecules are therefore suitable for investigation of the mechanisms involved when proteins fragment under electron capture dissociation (ECD). The dissociative recombination cross sections for both protonated DMDS and protonated N-methylacetamide were determined at electron energies ranging from 0.001 to 0.3 eV. Also, the branching ratios at 0 eV center-of-mass collision energy were determined. The present results give support for the indirect mechanism of ECD, where free hydrogen atoms produced in the initial fragmentation step induce further decomposition. We suggest that both indirect and direct dissociations play a role in ECD. 相似文献
63.
The thermal decompositions of zinc(II)benzenedicarboxylates were studied in air atmosphere at a heating-rate of 10 deg min–1. Zinc phthalate and isophthalate were dehydrated in one step and next decomposed directly to ZnO. Zinc terephthalate was dehydrated in two steps and then decomposed directly to ZnO.
Zusammenfassung Bei einer Aufheizgeschwindigkeit von 10°-min–1 wurde die thermische Zersetzung von Zink(II)benzoldikarboxylat in Luft untersucht. Zinkphtalat und -isophtalat wird zunächst in einem Schritt dehydratisiert und anschließend zu ZnO zersetzt. Zinkterephtalat wird vor der endgültigen Zersetzung zu ZnO in zwei Schritten dehydratisiert.
10 / . - . , .相似文献
64.
M. Kosmulski J. Szczypa J. Jabloński P. Golkiewicz 《Journal of Radioanalytical and Nuclear Chemistry》1991,150(2):465-471
A series of controlled pore glasses (CPG) was made from the same raw glass by means of different chemical and thermal treatments. BET specific area, selectivity of cesium adsorption in relation to sodium, ionosorption capacity under dynamic conditions of these CPG were measured and potentiometric titrations carried out. 0 vs. pH curves show i.e.p. and c.i.p. values similar to those for silica. KOH treatment leads to increase of BET specific surface but ionosorption capacity is decreased. 相似文献
65.
Marek Demiański Zdzislaw Golda Waldemar Puszkarz 《General Relativity and Gravitation》1991,23(8):917-939
We study the dynamics of the generalizedD-dimensional (D = 1+3+d) Friedman-Robertson-Walker (FRW) cosmological models in the framework of an extended gravity theory obtained by adding the Gauss-Bonnet term to the standard Einstein-Hilbert action. In our discussion we extensively use methods of dynamical systems. We consider models filled in with a perfect fluid obeying the equation of statep=(–1) and vacuum but non-flat models. We present a detailed analysis of the ten dimensional model and in particular we study the vacuum case. Several phase portraits show how the evolution of this model depends on the parameter. 相似文献
66.
Urszula Rychlewska Jacek Gawroński Krystyna Gawrońska 《Journal of chemical crystallography》1992,22(3):353-359
The carbon atom chain in the molecule ofd-glucitol hexa (p-chlorobenzoate) adopts a planar, zigzag conformation in the solid state, as determined by X-ray crystallography. The preference for such conformation in the crystal can be ascribed to the stacking interactions in which an infinite number of p-chlorobenzoyloxy substituents is involved. 相似文献
67.
Thermal decomposition of Bi(SCN)3, Cd(SCN)2, Pb(SCN)2 and Cu(SCN)2 has been studied. The thermal analysis curves and the diffraction patterns of the solid intermediate and final products of the pyrolysis are presented. The gaseous products of the decomposition (SO2 and CO2) were detected and quantitatively determined. Thermal, X-ray and chemical analyses have been used to establish the nature of the reactions occurring at each stage in the decomposition.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
68.
L. Wojtczak S. Romanowski W. Stasiak B. Mrygoń 《Czechoslovak Journal of Physics》1981,31(9):1024-1036
The density of electronic states and its spatial distribution in thin films are considered including the electron correlations in the coherent phase approximation applied to the intra-atomic interaction. This new approach allows us to derive the line shape for electronic levels which is important from the point of view of the convergency for the density function in the case of systems with restricted dimensions. Detailed calculations are performed for 4s copper film functions with the fcc lattice and various crystallographic orientations of the surfaces.The authors are very grateful to Professor L. Valenta (Prague) for his kind interest in this paper and to Dr. J. Mizia (Cracow) for helpful discussions. We would like to express our gratitude to Professor M. Wonicki and Mrs M. Firszt (Toru) for their help in obtaining the computer program procedure for two-particle interaction integrals calculations.The paper has been done in the framework of the Problem M.R I-11. 相似文献
69.
The wide class of nonextendible positive maps inC
*-algebras [1, 3] is studied. An example is given showing that the set of nonextendible positive maps betweenC
*-algebras
and
is not closed inL(
) in the weak topology. 相似文献
70.
J. Dembczyński W. Ertmer U. Johann S. Penselin P. Stinner 《Zeitschrift für Physik A Hadrons and Nuclei》1979,291(3):207-218
The hyperfine structure (hfs) of the metastable atomic states 3d64s6 D 1/2, 3/2, 5/2, 7/2, 9/2 of55Mn was measured using theABMR- LIRF method (atomicbeammagneticresonance, detected bylaserinducedresonancefluorescence). The hfs constantsA andB, corrected for second order hfs perturbations, could be derived from these measurements. The theoretical interpretation of these correctedA- andB-factors was performed in the intermediate coupling scheme taking into account the configurations 3d 54s 2, 3d 64s and 3d 7. Examining the influence of the composition of the eigenvectors on the hfs parameters \(\left\langle {r^{ - 3} } \right\rangle ^{k_s k_l } \) it was found, that for the configuration 3d 64s the two-body magnetic interaction should be considered in the calculation of the eigenvectors. Investigating second order electrostatic configuration interactions and relativistic effects and using calculated relativistic correction factors we obtained for the nuclear quadrupole moment of the nucleus55Mn a value ofQ=0.33(1) barn, which is not perturbed by a shielding or antishielding Sternheimer factor. The following hfs constants have been obtained: $$\begin{gathered} A\left( {{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 882.056\left( {12} \right)MHz \hfill \\ A\left( {{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 469.391\left( 7 \right)MHzB\left( {{3 \mathord{\left/ {\vphantom {3 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = - 65.091\left( {50} \right)MHz \hfill \\ A\left( {{5 \mathord{\left/ {\vphantom {5 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 436.715\left( 3 \right)MHzB\left( {{5 \mathord{\left/ {\vphantom {5 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = - 46.769\left( {30} \right)MHz \hfill \\ A\left( {{7 \mathord{\left/ {\vphantom {7 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 458.930\left( 3 \right)MHzB\left( {{7 \mathord{\left/ {\vphantom {7 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 21.701\left( {40} \right)MHz \hfill \\ A\left( {{9 \mathord{\left/ {\vphantom {9 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 510.308\left( 8 \right)MHzB\left( {{9 \mathord{\left/ {\vphantom {9 2}} \right. \kern-\nulldelimiterspace} 2}} \right) = 132.200\left( {120} \right)MHz \hfill \\ \end{gathered} $$ 相似文献