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31.
Todora Ojkova Donka Stoilova Dimitar Barkov 《Monatshefte für Chemie / Chemical Monthly》2000,14(1):1019-1023
The solubilities in the systems Rb2SeO4=ZnSeO4=H2O and Cs2SeO4=ZnSeO4=H2O at 25°C were studied by the method of isothermal decrease of supersaturation. Comparatively wide crystallization fields
of the double salts Rb2Zn(SeO4)2ċ6H2O and Cs2Zn(SeO4)2ċ6H2O are observed in the solubility diagrams. The double salts form monoclinic crystals which are isostructural with those of
the corresponding rubidium and cesium zinc sulfate hexahydrates. TG and TDA measurements indicate that the double salts lose
their crystallization water in one step in the temperature intervals of 50–160°C (rubidium salt) and 70–150°C (cesium salt). 相似文献
32.
Dimitar I. Dimitrov Andrey Milchev Kurt Binder Dieter W. Heermann 《Macromolecular theory and simulations》2006,15(7):573-583
Summary: Molecular dynamics simulations of a coarse‐grained bead‐spring model of flexible macromolecules tethered with one end to the surface of a cylindrical pore are presented. Chain length N and grafting density σ are varied over a wide range and the crossover from “mushroom” to “brush” behavior is studied for three pore diameters. The monomer density profile and the distribution of the free chain ends are computed and compared to the corresponding model of polymer brushes at flat substrates. It is found that there exists a regime of N and σ for large enough pore diameter where the brush height in the pore exceeds the brush height on the flat substrate, while for large enough N and σ (and small enough pore diameters) the opposite behavior occurs, i.e. the brush is compressed by confinement. These findings are used to discuss the corresponding theories on polymer brushes at concave substrates.
33.
For a solution of optically active compounds in liquid crystals, the infrared rotatory dispersion can be measured by Fourier transform spectroscopy. The results of a resolution enhancement by Fourier deconvolution and second derivative approach for the spectral features of the so-called A-Cotton effects are discussed. The experimental spectrum shown was recorded from a solution of cholesteryl oleyl carbonate in liquid crystal MBBA. 相似文献
34.
We describe the type of reasoning used in the typical fuzzy logic controller, the Mamdani reasoning method. We point out the basic assumptions in this model. We discuss the S-OWA operators which provide families of parameterized “andlike” and “orlike” operators. We generalize the Mamdani model by introducing these operators. We introduce a method, which we call Direct Fuzzy Reasoning (DFR), which results from one choice of the parameters. We develop some learning algorithms for the new method. We show how the Takagi-Sugeno-Kang (TSK) method of reasoning is an example of this DFR method. 相似文献
35.
Nikolina L. Petrova Dimitar S. Todorovsky Daniela G. Kovacheva Maria M. Milanova 《Central European Journal of Chemistry》2006,4(4):632-645
Al-and Y-Al-citric complexes have been synthesized in ethylene glycol medium at conditions close to the ones used in polymerized
complex method and their composition and spectral characteristics have been studied. Proofs have been found for the formation
in the bimetallic system of a mixed-metal Al-Y-complex. Doubly ionized and esterified ligands take place in the Al-complex.
All of the ligands forming Y-Al-complex are mono-or doubly esterified. Deprotonation of the alcoholic group takes place in
the formation of the mixed-metal complex. Both complexes contain adduct-bonded ethylene glycol. Heating of the bimetallic
complex or of the polyester resin formed leads to not phase-homogeneous YAlO3-along with cubic YAlO3, its orthorhombic modification as well as Y4Al
l2O9 are found by X-ray diffractometry. 相似文献
36.
Doz. Dr. Danail Bonchev Verginia Kamenska Dimitar Kamenski 《Monatshefte für Chemie / Chemical Monthly》1977,108(2):477-487
The information approach for describing electronic structures of atoms was developed and different information characteristics of chemical elements were determined on this basis. The information functions display interesting features and correlate with the properties of chemical elements. The spin information of the elements having a closed electron shell, expressed in bits, was found to be equal to the atomic number of the element.
Mit 8 Abbildungen 相似文献
Mit 8 Abbildungen 相似文献
37.
In the paper we prove a variant of the well known Filippov–Pliss lemma for evolution inclusions given by multivalued perturbations of m-dissipative differential equations in Banach spaces with uniformly convex dual. The perturbations are assumed to be almost upper hemicontinuous with convex weakly compact values and to satisfy one-sided Peron condition. The result is then applied to prove the connectedness of the solution set of evolution inclusions without compactness and afterward the existence of attractor of autonomous evolution inclusion when the perturbations are one-sided Lipschitz with negative constant. 相似文献
38.
Mariana S. Khristova Srdjan P. Petrović Ana Terlecki-Baričević Dimitar R. Mehandjiev 《Central European Journal of Chemistry》2009,7(4):857-863
The perovskite type oxides (nominal formula LaTi0.5Mg0.5O3) with addition of Pd were prepared by annealing the ethanol solution of precursors in nitrogen flow at 1200°C and characterized
by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption of NO (NO-TPD).
Their activity was evaluated for NO reduction by CO under stoichiometric and oxidizing conditions and for direct decomposition
of NO. Pd substituted samples exhibited high NO reduction activity and selectivity towards N2. Nearly complete elimination of NO was achieved at 200°C. Two simultaneous reactions, NO reduction by CO and direct decomposition
of NO as well as two forms of NO adsorption were observed on the surface of Pd substituted perovskite samples. The distribution
of Pd in different catalytically active sites or complexes on at the catalyst surface may be responsible for the proceeding
of two reactions: NO reduction with CO and direct NO decomposition.
相似文献
39.
40.
In this study, we describe a new approach for studying protein-DNA interactions in solution. The approach is based on mapping the UV laser-induced protein-DNA cross-links between the amino acids of the protein and the DNA bases that are in direct contact. The approach was applied for studying the solution structure of the human necrosis factor (NF)-kappaB p50 homodimer bound to a 37 base pair DNA. Several points of contact identical to those observed in the NF-kappaB-DNA crystal structure were found between the two biomolecules. Evidence is provided for the occurrence of two new contact points, one for each DNA strand. These new points of contact are located symmetrically a base apart from the extremity of the binding sequence. 相似文献