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831.
Maria Carta Leonarda Vugrin Dr. Goran Miletić Dr. Marina Juribašić Kulcsár Prof. Dr. Pier Carlo Ricci Dr. Ivan Halasz Prof. Dr. Francesco Delogu 《Angewandte Chemie (International ed. in English)》2023,62(33):e202308046
Typically induced by the mechanical processing of powders in ball mills, mechanochemical transformations are considered to result from the application of mechanical force to solid reactants. However, the undeniable deep connection between the dynamic compaction of powders during impacts and the overall transformation degree has yet to be disclosed. In the present work, we show that the square planar bis(dibenzoylmethanato)NiII coordination compound undergoes trimerization when its powder experiences even a single ball impact. Based on systematic experiments with individual ball impacts and analysis by Raman spectroscopy, we provide here quantitative mapping of the transformation in the powder compact and deduce bulk reaction kinetics from multiple individual impacts. 相似文献
832.
Pejić Bach Mirjana Topalović Amir Turulja Lejla 《Central European Journal of Operations Research》2023,31(3):941-973
Central European Journal of Operations Research - Data mining is the process of knowledge extraction from the data with the algorithms that identify hidden relationships and patterns, which are... 相似文献
833.
M. Boćkowski I. GrzegoryA. Kchahapuridze S. GierlotkaS. Porowski 《Journal of Crystal Growth》2010,312(18):2574-2578
In this work Ca3N2 was investigated as a potential flux for crystallization of GaN. Melting temperature of the potential flux at high N2 pressure evaluated by thermal analysis as 1380 °C is in good agreement with the theoretical prediction. It is shown that Ca3N2 present in the liquid gallium in small amount (1 at%) dramatically accelerates synthesis of GaN from its constituents. On the other hand, it does not influence significantly the rate of GaN crystallization from solution in gallium in temperature gradient for both unseeded and seeded configurations. However the habit and color of the spontaneously grown GaN crystals change drastically. For 10 mol% Ca3N2 content in the liquid Ga it was found that the GaN thick layer and GaN crystals (identified by micro-Raman scattering measurements) were grown on the substrate. For growth from molten Ca3N2 (100%) with GaN source, the most important observations were (i) GaN source material was completely dissolved in the molten Ca3N2 flux and (ii) after experiment, GaN crystals were found on the sapphire substrate. 相似文献
834.
Various Meir–Keeler-type conditions for mappings acting in abstract metric spaces are presented and their connections are discussed. Results about associated symmetric spaces, obtained in [S. Radenovi?, Z. Kadelburg, Quasi-contractions on symmetric and cone symmetric spaces, Banach J. Math. Anal. 5 (2011), 38–50] are used to show that the regularity condition for the underlying cone can be dropped in some fixed point results that have appeared recently. 相似文献
835.
Milojković-Opsenica Dusanka M. Lazarević Kristina Ivačković Vojkan Tešić Zivoslav Lj. 《平面色谱法杂志一现代薄层色谱法》2003,16(4):276-279
JPC – Journal of Planar Chromatography – Modern TLC - The chromatographic behavior of nine frequently used water-soluble food dyes has been studied by TLC on RP-18 silica gel.... 相似文献
836.
Paul S. Braterman Ronald J. Cross Ljubica Manojlović-Muir Kenneth W. Muir G.Brent Young 《Journal of organometallic chemistry》1975,84(3):C40-C42
The X-ray crystal structure analysis of cis-[PtPh2(Ph2PCH2PPh2)] suggests that the unusually low PtP coupling constant is a consequence of distortion of the valency angles at the platinum and phosphorus atoms; the restrictive geometry of the chelate ring does not effect the lengths of the metal—ligand bonds. 相似文献
837.
Knezević M Knezević D 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(3):3396-3398
We studied oscillatory behavior of critical amplitudes for the Gaussian model on a hierarchical structure presented by a modified Sierpinski gasket lattice. This model is known to display nonstandard critical behavior on the lattice under study. The leading singular behavior of the correlation length xi near the critical coupling K=K(c) is modulated by a function which is periodic in ln/ln(K(c)-K)/. We have also shown that the common finite-size scaling hypothesis, according to which for a finite system at criticality xi should be of the order of the size of the system, is not applicable in this case. As a consequence of this, the exact form of the leading singular behavior of xi differs from the one described earlier (which was based on the finite-size scaling assumption). 相似文献
838.
Nonlinear Dynamics - The presence of time-varying electromagnetic fields across a neuron cell may cause changes in its electrical characteristics, most notably, in the action potential dynamics.... 相似文献
839.
We propose an all-electrical nanostructure where pure spin current is induced in the transverse voltage probes attached to a quantum-coherent ballistic one-dimensional ring when unpolarized charge current is injected through its longitudinal leads. Tuning of the Rashba spin-orbit coupling in a semiconductor heterostructure hosting the ring generates quasiperiodic oscillations of the predicted spin-Hall current due to spin-sensitive quantum-interference effects caused by the difference in the Aharonov-Casher phase accumulated by opposite spin states. Its amplitude is comparable to that of the spin-Hall current predicted for finite-size (simply connected) two-dimensional electron gases, while it gets reduced gradually in wide two-dimensional rings or due to spin-independent disorder. 相似文献
840.
The quantitative electrochemical generation of bromine at a platinum electrode in acetic acid is described. Coulometric methods for the determination of hydroquinone and 2-methylhydroquinone are reported. The best results are obtained with 0.7–1.1 M potassium acetate solutions as supporting electrolyte, and biamperometric end-point detection. The effects of water and acetic anhydride on the accuracy of titrations are discussed. Determination of the formal redox potential of the Br2/Br- system in a 0.9 M potassium acetate solution in acetic acid showed that bromide is oxidized directly to bromine at a platinum electrode with 100% current efficiency. 相似文献