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81.
Zhao X Flaim E Huynh L Jarvis MJ Cheng P Lavrov VV Blagojevic V Koyanagi GK Bohme DK 《Inorganic chemistry》2006,45(24):9646-9653
Results are reported for experimental measurements of the room-temperature chemical reactions between ground-state Hg*+ ions and 16 important environmental and biological gases: SF6, CO, CO2, N2O, D2O, CH4, CH3F, O2, CH3Cl, OCS, CS2, NH3, C6F6, NO2, NO*, and C6H6. The inductively coupled plasma/selected-ion flow tube tandem mass spectrometer used for these measurements has provided both rate and equilibrium constants. Efficient electron transfer (>19%) is observed with CS2, NH3, C6F6, NO2, NO*, and C6H6, molecular addition occurs with D2O, CH4, CH3F, CH3Cl, and OCS, and SF6, CO, CO2, N2O, and O2 showed no measurable reactivity with Hg*+. Theory is used to explore the stabilities and structures of both the observed and unobserved molecular adducts of Hg*+, and reasonable agreement is obtained with experimental observations, given the uncertainties of the theory and experiments. A correlation is reported between the Hg*+ and proton affinities of the ligands investigated. Solvation of Hg*+ with formic acid was observed to increase the rate of electron transfer from NO* by more than 20%. 相似文献
82.
A systematic method for approximating the ab initio electronic energy of molecules from the energies of molecular fragments is tested on a large sample of typical organic molecular structures. The detailed methods, including some additional refinements for molecular rings and long range interactions, are described. The accuracy and computational efficiency of the systematic hierarchy of methods are reported. 相似文献
83.
Vitali Wachtel 《Probability Theory and Related Fields》2012,152(3-4):407-424
Let {S n ; n?≥?0} be an asymptotically stable random walk and let M n denote it’s maximum in the first n steps. We show that the asymptotic behaviour of local probabilities for M n can be approximated by the density of the maximum of the corresponding stable process if and only if the renewal mass-function based on ascending ladder heights is regularly varying at infinity. We also give some conditions on the random walk, which guarantee the desired regularity of the renewal mass-function. Finally, we give an example of a random walk, for which the local limit theorem for M n does not hold. 相似文献
84.
85.
Diogo Alexandre Siebert Flávia de Mello Michele Debiasi Alberton Luciano Vitali 《Natural product research》2020,34(18):2683-2688
AbstractAlzheimer’s disease and diabetes mellitus are contemporary diseases of great concern. Phenolic compounds are linked to several health benefits and could lead to novel strategies to combat these ailments. The objective of this study was to evaluate by electrophoretically-mediated microanalysis the potential inhibitory activity of the fruit juices from Plinia cauliflora (“jaboticaba”) and Eugenia uniflora (“pitanga”) toward acetylcholinesterase (AChE) and α-glucosidase, target enzymes in strategies for the treatment of these diseases. The phenolic profiles of the samples were also investigated. Jaboticaba and pitanga juices inhibited 85.90?±?1.73 and 52.67?±?1.24% of AChE activity at 5?mg mL?1, and 57.91?±?2.60 and 69.47?±?2.89% of α-glucosidase activity at 1?mg mL?1, respectively. Total phenolic content of the juices were 303.54?±?28.28 and 367.00?±?11.42 mgGA L?1, respectively. The observed inhibitory activity can be explained, at least in part, by the presence of the phenolic compounds. 相似文献
86.
We study the Banach spacesX with the following property: there is a numberδ in ]0,1[ such that for some constantC, any finite dimensional subspaceE ⊂X contains a subspaceF ⊂E with dimF≧δ dimE which isC-isomorphic to a Euclidean space. We show that if this holds for someδ in ]0,1[ then it also holds for allδ in ]0,1[ and we estimate the functionC=C(δ). We show that this property holds iff the “volume ratio” of the finite dimensional subspaces ofX are uniformly bounded. We also show that (althoughX can have this property without being of cotype 2)L
2(X) possesses this property iffX if of cotype 2. In the last part of the paper, we study theK-convex spaces which have a dual with the above property and we relate it to a certain extension property. 相似文献
87.
Two-sided bounds for the heat kernel of the Schrödingeroperator with a singular potential are obtained with explicitconstants. 1991 Mathematics Subject Classification 35B05, 35J10. 相似文献
88.
A simple interaction model is employed to show that radiation pressure effects, i.e., ponderomotive effects, can be profitably used to entangle radiation fields, as well as macroscopic oscillators such as movable mirrors. 相似文献
89.
Vitali Sinitsyn Koichi Hamamoto Yoshinobo Fujishiro Sergei Bredikhin Masanobu Awano 《Ionics》2006,12(3):211-213
A new multilayered electrochemical cell for NOx decomposition was prepared. The cell demonstrated good characteristics at moderate temperatures (350–450 °C) and possessed much higher selectivity with respect to NOx decomposition than previous one. It was found that the “crossover” process from high selective regime to the normal regime depends on the chemical composition of the catalytic electrode. 相似文献
90.