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81.
Tishchenko O Vinckier C Ceulemans A Nguyen MT 《The journal of physical chemistry. A》2005,109(27):6099-6103
The electronic structure aspects of the M (1S,3P) + N2O(X 1sigma+) (M = Be, Mg, Ca) reactions are investigated using the CASSCF/MRMP2 (complete active space SCF and the multireference M?ller-Plesset perturbation theory of the second order) computational methodology. The lowest adiabatic 1 1A' and 1 3A' potential energy surfaces (PESs) favor the bending dissociation mechanism of N2O in all studied cases. The rate-limiting channels are determined by the classical barriers that decrease in the series Be (8.9) > Mg (7.0) > Ca (1.2) kcal/mol, whereas the spin-forbidden reaction channels are found to be less important. A comparison with elaborated kinetic results (Plane et al. J. Phys. Chem. 1990, 94, 5255; Gas-Phase Metal Reactions; Elsevier: Amsterdam, 1992; Vinckier et al. J. Phys. Chem. A 1999, 103, 5328) on the Ca (1S) + N2O(X 1sigma+) reaction is presented, and the differences in the kinetic behavior of the title reactions are discussed. Our results also indicate that the techniques based on the multiconfigurational wave functions are unavoidable if a correct topology of the PESs governing these reactions is needed. 相似文献
82.
This work reports two-step synthesis of novel ordered mesoporous silicas (OMS), which contain mercury-specific multifunctional
ligand and have high surface area and well-developed porosity. One pot co-condensation synthesis was employed to introduce
chloropropyl functionality on the mesopore walls of hexagonally ordered silica. In the next step, 2,5-dimercapto-1,3,4-thiadiazole
was reacted with chloropropyl groups during template-displacement process, which resulted in high affinity adsorbent towards
mercury ions. The maximum adsorption capacity of this adsorbent for mercury ions from aqueous solutions was as high as 1.7
g/g, which is about three times higher than the concentration of surface ligand. This study shows that the surface properties
of OMS can be tailored by proper choice of chemical modification method, which affects the ligand bonding density and determines
the adsorbent capacity and affinity towards heavy metal ions. Three methods, one-pot synthesis, template-displacement and
post-synthesis modification, were used for the introduction of surface ligands into MCM41 and SBA15 mesostructures to prepare
mercury-specific adsorbents. In addition, adsorption properties of these adsorbents as well as their effectiveness for mercury
removal from aqueous solutions were comparatively studied. 相似文献
83.
84.
Oksana V. Dudka Vjacheslav A. Ksenofontov Alexei A. Mazilov Tatjana I. Mazilova Evgenij V. Sadanov 《辐射效应与固体损伤》2016,171(7-8):606-614
Using low-temperature field ion microscope techniques, we studied at the atomic level the elementary events of radiation-induced surface diffusion of tungsten adatoms on the ideally pristine surface. The experiments on surface-damage formation and adatom displacements have been performed in situ with a source of neutral helium atoms with an energy of 5?keV. It was demonstrated that the low-energy He atomic bombardment at grazing incidence was able to induce a substantial surface mobility of adatoms. Most of the radiation-induced adatom displacements were oriented along the direction of irradiation. The long impact-induced jumps of adatoms, spanning more than a nearest-neighbor distance, were revealed. Performed molecular dynamics simulations reproduce the general experimental trends and conclusions. 相似文献
85.
The notion of generations of monic polynomials such that the coefficients of each polynomial of the next generation coincide with the zeros of a polynomial of the current generation is introduced, and its relevance to the identification of endless sequences of new solvable many-body problems “of goldfish type” is demonstrated. 相似文献
86.
Sergiy Shklyar Georgiy Shevchenko Yuliya Mishura Vadym Doroshenko Oksana Banna 《Methodology and Computing in Applied Probability》2014,16(3):539-560
We study the problem of optimal approximation of a fractional Brownian motion by martingales. We prove that there exists a unique martingale closest to fractional Brownian motion in a specific sense. It shown that this martingale has a specific form. Numerical results concerning the approximation problem are given. 相似文献
87.
Oksana V. Gnedenko Yury V. MezentsevAndrey A. Molnar Andrey V. LisitsaAlexis S. Ivanov Alexander I. Archakov 《Analytica chimica acta》2013
A highly sensitive reverse sandwich immunoassay for the detection of human cardiac myoglobin (cMb) in serum was designed utilizing a gold nanoparticle (AuNP)-enhanced surface plasmon resonance (SPR) biosensor. First, a monoclonal anti-cMb antibody (Mab1) was covalently immobilized on the sensor surface. AuNPs were covalently conjugated to the second monoclonal anti-cMb antibody (Mab2) to form an immuno-gold reagent (Mab2-AuNP). The reverse sandwich immunoassay consists of two steps: (1) mixing the serum sample with Mab2-AuNP and incubation for the formation of cMb/Mab2-AuNP complexes and (2) sample injection over the sensor surface and evaluation of the Mab1/cMb/Mab2-AuNP complex formation, with the subsequent calculation of the cMb concentration in the serum. The biosensor signal was amplified approximately 30-fold compared with the direct reaction of cMb with Mab1 on the sensor surface. The limit of detection of cMb in a human blood serum sample was found to be as low as 10 pM (approx. 0.18 ng mL−1), and the inter-assay coefficient of variation was less than 3%. Thus, the developed SPR-based reverse sandwich immunoassay has a sensitivity that is sufficient to measure cMb across a wide range of normal and pathological concentrations, allowing an adequate estimation of the disease severity and the monitoring of treatment. 相似文献
88.
89.
David R. Worrall Si n L. Williams Anna Eremenko Natalie Smirnova Oksana Yakimenko Galina Starukh 《Colloids and surfaces. A, Physicochemical and engineering aspects》2003,230(1-3):45-55
We have studied the photophysics of anthracene adsorbed to photocatalytic silica–titania mixed oxide systems prepared by two different methods: a sol–gel synthesis and an impregnation route. The observed photophysics depend upon the method of synthesis, with the sol–gel prepared samples resulting in enhanced radical cation formation via static excited singlet state quenching. This mechanism, whilst operative, does not give rise to long-lived charge separation in the case of the impregnated samples. These results are discussed in terms of differing sample morphologies. 相似文献
90.