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1.
2.
In this paper we consider certain matrix equations in the field of Mikusiński operators, and construct a method for obtaining an approximate solution which allows working with numerical constants instead of operators. The theory of diagonally dominant matrices is applied for the analysis, existence and character of the obtained solutions. We introduce a method for determining approximate solutions of a discrete analogue for operational differential equations and give conditions for their existence. The error of the approximation is estimated. 相似文献
3.
Vukadin M. Leovac Goran A. Bogdanović Valerija I. Češljević Ljiljana S. Jovanović Sladjana B. Novaković Ljiljana S. Vojinović-Ješić 《Structural chemistry》2007,18(1):113-119
The ligand, salicylaldehyde Girard-T hydrazonium chloride, [H2SalGT]Cl (1), and two complexes [Cu(HSalGT)X2]·H2O (X = Br(2); Cl(3)) were synthesized and their crystal structures were determined by single-crystal X-ray analysis. In the two isostructural
complexes, the Cu(II) is located in a square-pyramidal environment, with the chelating ligand and one halogen atom in the
basal plane and the second halogen in the apical position. The most apparent structural difference between the 1 and its complexes 2 and 3 is the orientation of the N(CH3)3 group: in 1, it is practically coplanar to the rest of the molecule, while in 2 and 3 it is oriented to the side of the axially bonded halogen, which can be explained by the C–H…X intramolecular interactions.
The compounds were characterized by elemental analysis, molar conductivity, magnetic susceptibility and electronic absorption
spectra. 相似文献
4.
Nataša Pejić Slobodan Anić Vesna Kuntić Vladana Vukojević Ljiljana Kolar-Anić 《Mikrochimica acta》2003,143(4):261-267
A kinetic method is described for the microquantitative (microconcentration/microvolume) determination of rutin based on potentiometric monitoring of the concentration perturbations of the Bray-Liebhafsky (BL) oscillatory reaction being in a non-equilibrium stationary state close to a bifurcation point. The experiments are carried out in an open reactor. The response of the matrix system to perturbations by different concentrations of rutin ethanolic solutions is followed by a Pt-electrode. In the concentration range between 7.8×10–8moldm–3 and 9.1×10–6mol dm–3, we found a linear dependence of the maximal potential shift, Em, on the logarithm of the rutin concentrations. The unknown concentrations can be determined from the calibration curve up to an accuracy of ±5%. The detection limit is 3.6×10–8mol dm–3. The amount of required sample can be as small as 10µL. 相似文献
5.
6.
?. ?upi? S. Anic A. Terlecki-Bari?evi? Lj. Kolar-Ani? 《Reaction Kinetics and Catalysis Letters》1995,54(1):43-49
Behavior of the Bray-Liebhafsky oscillatory reaction in the presence of acid-base polymers with and without ferric ions is analyzed. The influence of hydrogen ions on the overall reaction is shown. 相似文献
7.
Lj. Kolar-Ani? Dj. Misljenovi? S. Ani? G. Nicolis 《Reaction Kinetics and Catalysis Letters》1995,54(1):35-41
The reduction of iodate ion by hydrogen peroxide, originally postulated by Liebhafsky, is considered as a possible step in the kinetic model proposed by Kolar-Ani and G. Schmitz for the overall Bray-Liebhafsky oscillatory process. 相似文献
8.
Huang Y Triscari JM Pasa-Tolic L Anderson GA Lipton MS Smith RD Wysocki VH 《Journal of the American Chemical Society》2004,126(10):3034-3035
Analysis of fragmentation patterns from 5654 unique doubly charged tryptic peptides is obtained. Great variability of average relative abundance of bond cleavage is found between different amino acid combinations. There exist similarities as well as differences between b and y ions. Strong enhancement or suppression of cleavage gives insight into possible chemical interactions at reactive conformations formed by preferred phi-psi angles. 相似文献
9.
G. Schmitz Lj. Kolar-Anić 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(9):1380-1387
It has been known for a long time that the decomposition of hydrogen peroxide catalyzed by hydrogen and iodate ions, the Bray-Liebhafsky
reaction, can generate oscillations in a batch reactor. Recently, mixed-mode oscillations and chaos have also been observed
in a CSTR. The model we had previously proposed to explain the kinetics in a batch reactor can also simulate these new complex
behaviors. Time series give only a limited view of the features of the calculated behaviors and more information is obtained
studying the properties of the state space. We use projections of the trajectories, calculation of the correlation dimension
of the attractor, Poincaré sections, and return maps. As the state space of the model is six-dimensional, we try to answer
the questions of whether the projections into a 3D subspace give correct pictures of the real trajectories and whether we have reasons to prefer a special subspace.
The text was submitted by the authors in English. 相似文献
10.
Schultz J Gottlieb DM Petersen M Nesic L Jacobsen S Søndergaard I 《Electrophoresis》2004,25(3):502-511
Methods for classification of two-dimensional (2-DE) electrophoresis gels based on multivariate data analysis are demonstrated. Two-dimensional gels of ten wheat varieties are analyzed and it is demonstrated how to classify the wheat varieties in two qualities and a method for initial screening of gels is presented. First, an approach is demonstrated in which no prior knowledge of the separated proteins is used. Alignment of the gels followed by a simple transformation of data makes it possible to analyze the gels in an automated explorative manner by principal component analysis, to determine if the gels should be further analyzed. A more detailed approach is done by analyzing spot volume lists by principal components analysis and partial least square regression. The use of spot volume data offers a mean to investigate the spot pattern and link the classified protein patterns to distinct spots on the gels for further investigation. The explorative approach in analysis of 2-D gels makes it possible, in a fast and convenient way, to screen many gels in order to determine the protein patterns that form clusters and could be selected for further examination. 相似文献