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91.
Gy. Vankó L. Bottyán D. L. Nagy E. Szilágyi A. Vértes 《Journal of Radioanalytical and Nuclear Chemistry》2000,246(1):97-100
Nuclear inelastic resonant scattering of synchrotron radiation was applied to the study solutions of 57Fe complexes. In order to reveal different inelastic contributions solutions of two different 57Fe complexes of different molecular dimensions with solvents of substantially different viscosities were studied. We argue that the only former experiment available in the literature overestimates the role of the diffusivity in affecting the spectrum. The first direct observation of an intramolecular vibrational transition assisting the nuclear resonance absorption in a liquid is reported. 相似文献
92.
The possibilities for reducing the necessary computation power in wavelet-based electronic structure calculations are studied. The expansion of the expectation values of energy operators, the integrals of basis functions are mostly system-independent, consequently it is not necessary to compute them in each calculations. Fixed building blocks, such as a parameterized expansion of the nuclear and electron–electron cusp can reduce the amount of necessary calculation. An algorithm for local expansion refinement is also given. It is possible to determine the significant expansion coefficients of a high resolution level without solving the Schrödinger equation using only lower resolution results. 相似文献
93.
94.
For the electrodeposition of119Sn, aluminium, iron, nickel, copper, silver and platinum foil substrates were used. The samples were measured before and after heat-treatments between 350–485 K. In several cases interphase formation was observed even before the first heat treatment. Diffusion data were alsc obtained. 相似文献
95.
96.
Ákos Kuki Miklós Nagy Lajos Nagy Miklós Zsuga Sándor Kéki 《Journal of the American Society for Mass Spectrometry》2010,21(9):1561-1564
The complex formation in solution, and the gas-phase dissociation of a phenanthrolineterminated poly(ethylene glycol) with
Fe2+ ions were investigated. The size distribution of poly(ethylene glycol)-α-monomethyl-ω-5-[1,10]phenanthroline (mPEG_phen)
was determined by electrospray ionization mass spectrometry (ESI-MS). Based on the measured ligand size distribution of mPEG_phen
by ESI-MS, the 1:3 complex formation (Fe2+/mPEG_Phen) was computer-simulated as a pure random assembly process. The simulated distribution fits excellently to that
of the complex Fe(mPEG_phen)32+ determined from the ESI-MS intensities. In addition, the collision-induced dissociation (CID) of the Fe(mPEG_phen)32+ complex was also studied by tandem mass spectrometry (ESI-MS/MS) and by computer simulation, as well. The ESI-MS/MS intensity
distribution of the Fe(mPEG_phen)22+ formed from Fe(mPEG_phen)32+ by the loss of an mPEG_phen ligand under CID conditions fits quite well to the calculated one. 相似文献
97.
In the case of several formaldehyde derivatives, with importance in atmospheric and combustion chemistry, the currently available thermochemical values suffer from considerably large uncertainties. In this study a high-accuracy theoretical model chemistry has been used to provide accurate thermochemical data including heats of formation at 0 and 298 K and standard molar entropies at 298 K for CF(2)O, FCO, HFCO, HClCO, FClCO, HOCO, and NH(2)CO. For most of the thermochemical quantities studied here, this investigation delivers the best available estimate. 相似文献
98.
First-principles calculations are presented for the layered perovskite Ca3Mn2O7. The results reveal a rich set of coupled structural, magnetic, and polar domains in which oxygen octahedron rotations induce ferroelectricity, magnetoelectricity, and weak ferromagnetism. The key point is that the rotation distortion is a combination of two nonpolar modes with different symmetries. We use the term "hybrid" improper ferroelectricity to describe this phenomenon and discuss how control over magnetism is achieved through these functional antiferrodistortive octahedron rotations. 相似文献
99.
Attila Nagy 《Semigroup Forum》2014,89(2):475-478
A semigroup S is called a weakly commutative semigroup if, for every a,b∈S, there is a positive integer n such that (ab) n ∈Sa∩bS. A semigroup S is called archimedean if, for every a,b∈S, there are positive integers m and n such that a n ∈SbS and b m ∈SaS. It is known that every weakly commutative semigroup is a semilattice of weakly commutative archimedean semigroups. A semigroup S is called a weakly separative semigroup if, for every a,b∈S, the assumption a 2=ab=b 2 implies a=b. In this paper we show that a weakly commutative semigroup is weakly separative if and only if its archimedean components are weakly cancellative. This result is a generalization of Theorem 4.16 of Clifford and Preston (The Algebraic Theory of Semigroups, Am. Math. Soc., Providence, 1961). 相似文献
100.
Gábor P. Nagy 《Designs, Codes and Cryptography》2014,72(1):153-164
For quasifields, the concept of parastrophy is slightly weaker than isotopy. Parastrophic quasifields yield isomorphic translation planes but not conversely. We investigate the right multiplication groups of finite quasifields. We classify all quasifields having an exceptional finite transitive linear group as right multiplication group. The classification is up to parastrophy, which turns out to be the same as up to the isomorphism of the corresponding translation planes. 相似文献