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11.
We derive scaling forms for the thermodynamic and correlation quantities for the turn-weighted fully and partially directed self-avoiding walks on the hypercubic lattices ind2. In the grand canonical (fixed fugacity per step) ensemble, the conformational rod-to-coil transition sets up in the regimew¯N=O(1), wherew is the weight of each 90° turn and¯N is the (fugacity-dependent) average number of steps. Contrary to the conventional critical phenomena wisdom, the scaling functions for the two different walk models, directed and partially directed, become universal only in the limitd. 相似文献
12.
I. B. Plećaš A. D. Perić S. D. Glodić A. M. Kostadinović 《Journal of Radioanalytical and Nuclear Chemistry》1992,166(5):373-381
Results are presented of a series of experimental tests performed to determine the influence of matrix characteristics on the leaching mechanism of copper aluminium oxychloride immobilized into cement matrices. The objective of this research was to investigate the leaching mechanism of copper as a constituent of copper aluminium oxychloride (CAOX). 相似文献
13.
Mladen Pavičić 《Foundations of Physics》1989,19(8):999-1016
Unified quantum logic based on unified operations of implication is formulated as an axiomatic calculus. Soundness and completeness are demonstrated using standard algebraic techniques. An embedding of quantum logic into a new modal system is carried out and discussed.On leave of absence from Department of Mathematics, University of Zagreb, Pot. Pret. 165, YU-41001 Zagreb, Yugoslavia. 相似文献
14.
Dodecaynes 1a-d have been prepared via a convergent strategy that employs Sonogashira couplings as the carbon-carbon bond-forming tool. Due to the steric bulk of the DMTS groups, 1c adopts a nonplanar conformation, the dynamics of which have been probed by VT-NMR. The cobalt-catalyzed isomerization of 1a,b produced the new conjugated phenylenes 2a,b and 3a,b, respectively. [structure: see text] 相似文献
15.
Summary Kinetics of dehydration of equilibrium swollen poly(acrylic acid) hydrogel was investigated using methods of non-isothermal
thermal analysis. Methods of Kissinger, Coats-Redfern, Van Krevelen and Horowitz-Metzger were applied for determination the
kinetics parameters: activation energy (E), pre-exponent (lnA) as well as the kinetics model ƒ(69) for the process of hydrogel dehydration under different heating rates. An existence
of good agreement between determined values of kinetic parameters (Eand A), which were obtained applying different methods under the same heating rate. Functional relationship between changes of
kinetic parameters of dehydration and changes of heating rate was established. An existence of compensation effect is accepted
and explanation of compensation effect appearance during the hydrogel dehydration is suggested. 相似文献
16.
R.R. Adžić D.N. Simić A.R. Despić D.M. Dražić 《Journal of Electroanalytical Chemistry》1975,65(2):587-601
It was demonstrated that some foreign metal monolayers formed by underpotential deposition have pronounced catalytic effects on the oxidation of formic acid on platinum. The explanation of these effects was sought within the framewor of existing data on the formic acid oxidation and the underpotential deposition. It was found that the catalytic effect of foreign metal monolayers originates in the decrease of hydrogen adsorption thus preventing the formation of the main poisoning species COH. At the same time these experiments confirm the previously postulated mechanism of formation of the poisoning species involving adsorbed hydrogen. 相似文献
17.
We report measured Stark shifts and widths of neutral flourine and chlorine lines. Wall stabilized arc is used as a plasma source. Electron densities 2–4×1022 m?3 are determined from the width of theH β line and electron temperatures 9500–10 000 K from plasma composition data. Experimental results for FI and ClI Stark widths and FI Stark shifts agree within 10% with semiclassical calculations. ClI Stark shifts are systematically smaller for about 20% than theoretical data with the only exception of the line from multiplet no. 15 where the discrepancy goes up to 49%. Results of investigation of similarities and regularities of Stark widths are in agreement with the study of Wiese and Konjevi?. Comparison of experimental Stark shifts shows certain types of regularities. 相似文献
18.
Summary From studies of aqueous solutions of dodecylammoniumnitrate an association mechanism has been proposed involving multiequilibrium. In the concentration range considered we can differentiate between two aspects: ranges of marked qualitative and quantitative changes and formation of differently structured surfactant species.
Zusammenfassung Aus der Untersuchung wäßriger Lösungen von Dodecylammoniumnitrat würde ein Assoziationsmechanismus abgeleitet, welcher ein Multiequilibrium beinhaltet. Im untersuchten Konzentrationsbereich können zwei Bereiche unterschieden werden: Bereiche mit ausgeprägten qualitativen und quantitativen Änderungen und Bereiche mit der Bildung von verschieden strukturierten oberflächenaktiven Spezies.相似文献
19.
Zusammenfassung Die Temperaturabhängigkeit der Viskosität im System LiNO3–H2O und im Temperaturbereich 20–70°C wird in der Gleichung =A expB/T=T
0 zusammengefaßt; aus der so erhaltenen Beziehung werden Rückschlüsse auf die Struktur der Lösungen gezogen.
Temperature dependence of the viscosity in the system LiNO3–H2O is expressed by =A expB/T-T 0 in the temperature range 20–70°C. Possible relations to structural changes in the solutions are considered.相似文献
20.
Tomislav Došlić 《Journal of mathematical chemistry》2007,41(3):217-229
A global forcing set in a simple connected graph G with a perfect matching is any subset S of E(G) such that the restriction of the characteristic function of perfect matchings of G on S is an injection. The number of edges in a global forcing set of the smallest cardinality is called the global forcing number
of G. In this paper we prove several results concerning global forcing sets and numbers of benzenoid graphs. In particular, we
prove that all catacondensed benzenoids and catafused coronoids with n hexagons have the global forcing number equal to n, and that for pericondensed benzenoids the global forcing number is always strictly smaller than the number of hexagons. 相似文献