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91.
Á. Császár 《Acta Mathematica Hungarica》2000,86(1-2):83-87
The purpose of the present paper is to show that the concept of topogenous order, introduced in [1] and discussed in detail in [2], can be useful in answering questions concerning transitive quasi-uniformities. 相似文献
92.
M. Csanád B. Tomášik T. Csörgő 《The European Physical Journal A - Hadrons and Nuclei》2008,37(1):111-119
We present a calculation of the elliptic flow and azimuthal dependence of the correlation radii in the ellipsoidally symmetric
generalization of the Buda-Lund model. The elliptic flow is shown to depend only on the flow anisotropy while in case of correlation
radii both flow and space anisotropy play an important role in determining their azimuthal oscillation. We also outline a
simple procedure for determining the parameters of the model from data. 相似文献
93.
The Staudinger ketene-imine cycloaddition reactions of cyclobrassinin phytoalexin analogues 2-aryl-4,9-dihydro-1,3-thiazino[6,5-b]indoles with chloroacetyl chloride as a ketene source were investigated under different conditions. Both β-lactam ring formation and the N-chloroacetylation of the indole moiety took place. The indole N-chloroacetyl group can be easily removed by treatment in the presence of silica gel in methanol at reflux temperature. The selective β-lactam formation can be also achieved in certain cases under milder Staudinger conditions. The treatment of azeto[2,1-b]thiazino[6,5-b]indole-1-one derivatives with sodium ethoxide in ethanol provided the novel thiazepino[7,6-b]indole ring systems in a one-step ring transformation. The structures of the new ring systems were determined by means of IR and NMR spectroscopy. 相似文献
94.
Attila G. Császár Prof. Dr. Tibor Furtenbacher Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(16):4826-4835
A simple and fast, weighted, linear least‐squares refinement protocol and code is presented for inverting the information contained in a network of quantum chemically computed 0 K reaction enthalpies. This inversion yields internally consistent 0 K enthalpies of formation for the species of the network. The refinement takes advantage of the fact that the accuracy of computed enthalpies depends strongly on the quantum‐chemical protocol employed for their determination. Different protocols suffer from different sources of error; thus, the reaction enthalpies computed by them have “random” residual errors. Since it is much more natural for quantum‐chemical energy and enthalpy results, including reaction enthalpies, to be based on the electronic ground states of the atoms and not on the historically preferred elemental states, and since these two possible protocols can be converted into each other straightforwardly, it is proposed that first‐principles thermochemistry should employ the ground electronic states of atoms. In this scheme, called atom‐based thermochemistry (AT), the enthalpy of formation of a gaseous compound corresponds simply to the total atomization energy of the species; it is always positive, and it reflects the bonding strength within the molecule. The inversion protocol developed and based on AT is termed NEAT, which represents the fact that the protocol proceeds from a network of computed reaction enthalpies toward atom‐based thermochemistry, most directly to atom‐based enthalpies of formation. After assembling a database that consisted of 361 ab initio reactions and reaction enthalpies involving 188 species, collected from 31 literature sources, the following dependable 0 K atom‐based enthalpies of formation, Δf${H{{{\rm AT}\hfill \atop 0\hfill}}}$ , all in kJ mol?1, have been obtained by means of NEAT: H2=432.07(0), CH=334.61(15), NH=327.69(25), OH=425.93(21), HF=566.13(31), CO=1072.08(28), O2=493.51(34), CH2=752.40(21), H2O=918.05(20), HO2=694.53(32), CO2=1597.77(40), CH3=1209.64(29), NH3=1157.44(33), C2H2=1625.78(40), and CH4=1641.68(40), in which the uncertainty values given in parentheses represent 95 % confidence intervals. The average deviation of these values from the well‐established active thermochemical tables (ATcT) values is a mere 0.25 kJ mol?1, with a maximum deviation of 0.7 kJ mol?1. This shows that the use of a large number of ab initio reaction enthalpies within a NEAT‐type protocol has considerable advantages over the sequential utilization of the ab initio information. 相似文献
95.
A. Ster M. Csanád T. Cs?rg? B. L?rstad B. Tomásik 《Physics of Particles and Nuclei Letters》2011,8(9):995-999
Identified particle spectra of pions, kaons and (anti)protons, and elliptic flow and azimuthal dependence of Bose-Einstein
or HBT correlations of identified pions in s
NN
= 200 GeV Au + Au collisions is analyzed simultaneously using an ellipsoidally symmetric generalization of the Buda-Lund
hydrodynamical model. The transverse flow is found to be faster in the reaction plane than out of plane, which results in
a reaction zone that gets slightly more elongated in-plane than out of plane. 相似文献
96.
We propose a homological approach to two conjectures descended from the Erdös-Ko-Rado Theorem, one due to Chvátal and the other to Frankl and Füredi. We apply the method to reprove, and in one case improve, results of these authors related to their conjectures. 相似文献
97.
Á. Császár 《Acta Mathematica Hungarica》2008,119(1-2):197-200
A quasi-topology is a generalized topology (cf. [3]) closed for finite intersections. The paper discusses the question whether statements valid for topologies can be generalized for quasi-topologies. 相似文献
98.
99.
M. Varsányi E. Kuzmann Cs. Vértes A. Vértes S. Vitkova G. Raichewski 《Hyperfine Interactions》1992,69(1-4):735-738
Mössbauer spectroscopy was used in order to study the influence of electrochemical behaviour of electrochemically deposited Fe—8P amorphous alloy. Electrochemically deposited amorphous samples were exposed to corrosion in the solution of H2SO4 and Na2SO4 containing NaHSO3 at pH=3.5. CEM spectra of as-deposited samples exhibit a typical sextet of ferromagnetic amorphous state. Even with samples being kept under corrosion condition for 10 minutes, the Mössbauer spectra reveal an extra Fe(III) component. 相似文献
100.
It is shown that the conditions claimed to transform the algebraic version of the Resonating-Group Model, originally invented for scattering problems, into a complex eigenvalue problem corresponding to resonant states are necessary but not sufficient. This can be concluded from the fact that false resonances are produced along with true ones. They can be distinguished and discarded by introducing an arbitrary non-linear parameter. The true solutions are invariant against this parameter but the false ones can be swept out even into non-physical regions of the energy.Devoted to Prof. E.W.Schmid on the occasion of his 60th birthday 相似文献