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91.
The invariant environment refinement technique, as applied to reverse Monte Carlo modelling [invariant environment refinement technique + reverse Monte Carlo (INVERT + RMC); M. J. Cliffe, M. T. Dove, D. A. Drabold, and A. L. Goodwin, Phys. Rev. Lett. 104, 125501 (2010)], is extended so that it is now applicable for interpreting the structure factor (instead of the pair distribution function). The new algorithm, called the local invariance calculation, is presented by the examples of amorphous silicon, phosphorus, and liquid argon. As a measure of the effectiveness of the new algorithm, the ratio of exactly fourfold coordinated Si atoms was larger than obtained previously by the INVERT-RMC scheme. 相似文献
92.
Abstract We present a theoretical study of the Light-Induced Fréedricksz transition in two geometries where dynamical phenomena induced by the laser light have been observed. We consider a spatially extended system, i.e. we assume the laser beam to be much wider than the thickness of the cell. We suggest that pattern formation phenomena in the plane of the cell entirely due to the light-director interaction should be possible to observe. 相似文献
93.
Sándor Bátori Dorottya Csányi Daniella Takács Orsolya Egyed Zsuzsanna Riedl György Hajós 《Tetrahedron》2019,75(2):180-185
N-aminopyridyl ketone salts were reacted with formamide to yield heteroaromatic pyrido[2,1-f][1,2,4]triazinium salts. Upon storage of these products in the presence of water, formation of covalent hydrates have been observed. Reaction of the same starting compound with urethane yielded 3-chloropyrido[2,1-f][1,2,4]triazinium salt which readily reacted with secondary amines to afford 3-amino derivatives. An analogous ring closure reaction of 2-formylaminomethyl- and formaminobenzylpyridine allowed the synthesis of the partially reduced 3,4-dihydropyrido[2,1-f][1,2,4]triazinium compounds. The cyclization procedure was also applied for the synthesis of the related pyrimido[2,1-f][1,2,4]triazinium salt. 相似文献
94.
Kéri Orsolya Bárdos Péter Boyadjiev Stefan Igricz Tamás Nagy Zsombor Kristóf Szilágyi Imre Miklós 《Journal of Thermal Analysis and Calorimetry》2019,137(4):1249-1254
Journal of Thermal Analysis and Calorimetry - In this work, polyvinylpyrrolidone/titanium tetraisopropoxide (PVP/TTIP) composite nanofibers were prepared by electrospinning from alcoholic... 相似文献
95.
NMR studies showed that, in addition to the expected N(1) protonation, 2,4,6-pyrimidinetriamine, N,N,N',N',N",N"-hexamethyl- (1) could also be protonated at the C(5) position in water, leading to an equilibrium between the C(5) and N(1) protonated forms. Analysis of the NMR titration data gives 6.87 and 6.89 for the pK(a) of the C(5) and N(1) protonation equilibria. Moreover, the reaction of 1 with chloroacetyl chloride leads to a novel 1,1-bis(pyrimidin-5-yl)-2-chloroethene type derivative (4) that is, peculiarly, fully monoprotonated at the C(5) position in either of the pyrimidine rings, forming a stable cationic sigma-complex. 相似文献
96.
Employing multireference variational (MRCI) and coupled cluster (CC) methods combined with quadruple-zeta quality correlation-consistent basis set, we have studied 36 states of the magnesium diboride (MgB(2)) molecule as well as 17 states of the experimentally unknown diatomic MgB. For all states of MgB(2), we report geometries, atomization energies, and dipole moments, while for the first 5 states, potential energy profiles have been also constructed. The ground state is formally of (1)A(1) V-shaped symmetry with an atomization energy of 108.1(109) kcal/mol at the MRCI(MRCI + Davidson correction) level. The first excited state ((3)B(1)) is less than 1 kcal/mol above the X(1)A(1) state, with the next state of linear Mg-B-B geometry (b(3)Sigma(-)) located 10 kcal/mol higher. In all states, bent or linear, the bonding is complicated and unconventional because of the extraordinary bonding agility of the boron atom(s). 相似文献
97.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. 相似文献
98.
Orsolya Kri Eszter Kocsis Dniel Attila Karajz Zsombor Kristf Nagy Bence Parditka Zoltn Erdlyi Anna Szab Klra Herndi Imre Mikls Szilgyi 《Molecules (Basel, Switzerland)》2021,26(19)
In this work core/shell composite polymer/TiO2 nanofibers and from those TiO2 nanotubes were prepared. First, poly(vinyl alcohol) (PVA) and poly(vinylpyrrolidone) (PVP) fibers were synthetized by electrospinning. They were covered with a 100 nm thick amorphous TiO2 layer by atomic layer deposition at 50 °C. Later the polymer core was removed by two different methods: dissolution and annealing. In the case of dissolution in water, the as-prepared TiO2 nanotubes remained amorphous, while when annealing was used to remove the polymers, the TiO2 crystallized in anatase form. Due to this, the properties of amorphous and crystalline TiO2 nanotubes with exactly the same structure and morphology could be compared. The samples were investigated by SEM-EDX, ATR-IR, UV-Vis, XRD and TG/DTA-MS. Finally, the photocatalytic properties of the TiO2 nanotubes were studied by decomposing methyl-orange dye under UV light. According to the results, crystalline anatase TiO2 nanotubes reached the photocatalytic performance of P25, while amorphous TiO2 nanotubes had observable photocatalytic activity. 相似文献
99.
Gábor Molnár Sándor Gaál Orsolya Kóréh József Borossay 《Rapid communications in mass spectrometry : RCM》1997,11(6):683-685
In thermally stimulated exoelectron emission (TSEE) dosimetry the irradiation is generally executed in air while the read out is in methane. Under these conditions adsorption/desorption effects appear which influence the exoemission. BeO:Li and BeO:TiO2 ceramics were compared from this point of view. The effect of adsorption/desorption was studied in such a way that in the cycles of irradiation/read-out the cooling down was executed successively in a methane atmosphere or in air. The TSEE curves of the BeO:TiO2 ceramic were more influenced by the cooling atmosphere than those of the BeO:Li ceramic. In order to explain this result the thermal desorption spectra of these materials was taken. © 1997 John Wiley & Sons, Ltd. 相似文献
100.
Dr. Gyula Pálfy Dr. Dóra K. Menyhárd Hanna Ákontz-Kiss István Vida Prof. Dr. Gyula Batta Dr. Orsolya Tőke Prof. Dr. András Perczel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(59):e202201449
For efficient targeting of oncogenic K-Ras interaction sites, a mechanistic picture of the Ras-cycle is necessary. Herein, we used NMR relaxation techniques and molecular dynamics simulations to decipher the role of slow dynamics in wild-type and three oncogenic P-loop mutants of K-Ras. Our measurements reveal a dominant two-state conformational exchange on the ms timescale in both GDP- and GTP-bound K-Ras. The identified low-populated higher energy state in GDP-loaded K-Ras has a conformation reminiscent of a nucleotide-bound/Mg2+-free state characterized by shortened β2/β3-strands and a partially released switch-I region preparing K-Ras for the interaction with the incoming nucleotide exchange factor and subsequent reactivation. By providing insight into mutation-specific differences in K-Ras structural dynamics, our systematic analysis improves our understanding of prolonged K-Ras signaling and may aid the development of allosteric inhibitors targeting nucleotide exchange in K-Ras. 相似文献