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11.
R. A. Kotel’nikova G. N. Bogdanov G. V. Zotina V. S. Romanova Z. N. Parnes 《Physics of the Solid State》2002,44(3):576-577
Efficient quenching of eosin phosphorescence by amino-acid derivatives of fullerene (AADFs) such as C60-alanine and C60-glycine in aqueous solutions indicates the possibility of transferring electrons from eosin to fullerene upon collisions or in the exciplex state. To investigate electron transfer in the protein structure, we studied the process of incorporation of C60-alanine and C60-glycine into the heme pocket of myoglobin by controlling Förster quenching. The dissociation constant for the protein-AADF complex was estimated. 相似文献
12.
Ivan Kojadinovic 《4OR: A Quarterly Journal of Operations Research》2007,5(2):117-142
The application of multi-attribute utility theory based on the Choquet integral requires the prior identification of a capacity
if the utility scale is unipolar, or of a bi-capacity if the utility scale is bipolar. In order to implement a minimum distance
principle for capacity or bi-capacity approximation or identification, quadratic distances between capacities and bi-capacities
are studied. The proposed approach, consisting in solving a strictly convex quadratic program, has been implemented within
the GNU R kappalab package for capacity and nonadditive integral manipulation. Its application is illustrated on two examples.
相似文献
13.
Andrew Mills Anne Lepre Nicholas Elliott Sharan Bhopal Ivan P. Parkin S. A. ONeill 《Journal of photochemistry and photobiology. A, Chemistry》2003,160(3):213-224
Pilkington Glass Activ™ represents a possible suitable successor to P25 TiO2, especially as a benchmark photocatalyst film for comparing other photocatalyst or PSH self-cleaning films. Activ™ is a glass product with a clear, colourless, effectively invisible, photocatalytic coating of titania that also exhibits PSH. Although not as active as a film of P25 TiO2, Activ™ vastly superior mechanical stability, very reproducible activity and widespread commercial availability makes it highly attractive as a reference photocatalytic film. The photocatalytic and photo-induced superhydrophilitic (PSH) properties of Activ™ are studied in some detail and the results reported. Thus, the kinetics of stearic acid destruction (a 104 electron process) are zero order over the stearic acid range 4–129 monolayers and exhibit formal quantum efficiencies (FQE) of 0.7×10−5 and 10.2×10−5 molecules per photon when irradiated with light of 365±20 and 254 nm, respectively; the latter appears also to be the quantum yield for Activ™ at 254 nm. The kinetics of stearic acid destruction exhibit Langmuir–Hinshelwood-like saturation type kinetics as a function of oxygen partial pressure, with no destruction occurring in the absence of oxygen and the rate of destruction appearing the same in air and oxygen atmospheres. Further kinetic work revealed a Langmuir adsorption type constant for oxygen of 0.45±0.16 kPa−1 and an activation energy of 19±1 kJ mol−1. A study of the PSH properties of Activ™ reveals a high water contact angle (67°) before ultra-bandgap irradiation reduced to 0° after prolonged irradiation. The kinetics of PSH are similar to those reported by others for sol–gel films using a low level of UV light. The kinetics of contact angle recovery in the dark appear monophasic and different to the biphasic kinetics reported recently by others for sol–gel films [J. Phys. Chem. B 107 (2003) 1028]. Overall, Activ™ appears a very suitable reference material for semiconductor film photocatalysis. 相似文献
14.
Anelia Achanova Ivan Zhelyazkov Tsvetelina Petrova 《Czechoslovak Journal of Physics》2004,54(2):211-223
Microwave discharges produced by travelling/standing electromagnetic waves have drawn considerable attention in recent years
due to their wide application in microelectronic industry. Here are presented the axial distributions of the electrons and
ions as well as those of excited atoms in an argon microwave discharge at a low gas pressure (400 mTorr) sustained by a 2.45
GHz travelling dipolar electromagnetic wave. The numerical calculations are based on a self-consistent kinetic-electrodynamic
model and the results obtained are in a good agreement with the experimental data. The model yields also the magnitude of
the wave power sustaining the discharge and the axial profiles of all electromagnetic-wave characteristics and the axial distribution
of the neutral gas temperature. 相似文献
15.
E. A. Bogdanov A. A. Kudryavtsev L. D. Tsendin R. R. Arslanbekov V. I. Kolobov V. V. Kudryavtsev 《Technical Physics》2003,48(9):1151-1158
Comprehensive self-consistent simulations of the positive column plasma of a dc oxygen discharge are performed with the help
of commercial CFDRC software (), which enables one to carry out computations in an arbitrary 3D geometry using fluid equations for heavy components and
a kinetic equation for electrons. The main scaling laws for the spatial distributions of charged particles are determined.
These scaling laws are found to be quite different in the parameter ranges that are dominated by different physical processes.
At low pressures, both the electrons and negative ions in the inner discharge region obey a Boltzmann distribution; as a result,
a flat profile of the electron density and a parabolic profile of the ion density are established there. In the ion balance,
transport processes prevail, so that ion heating in an electric field dramatically affects the spatial distribution of the
charged particles. At elevated pressures, the volume processes prevail in the balance of negative ions and the profiles of
the charged particle densities in the inner region turn out to be similar to each other. 相似文献
16.
V. A. Dorokhov A. R. Amamchyan V. S. Bogdanov B. I. Ugrak 《Russian Chemical Bulletin》1991,40(1):222-224
A method is proposed for the synthesis of N-substituted 5-azaadenines. The condensation of N-(1,2,4-triazol-5-yl)amidines with trichloroacetonitrile gives trichloromethyl derivatives of 1,2,4-triazolo[1,5-a]-1,3,5-triazines, which are converted by the action of primary or secondary amines into N-alkylamino- or N,N-dialkylamino-1,2,4-triazolo-[1,5-a]-1,3,5-triazines (5-azaadenines).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 241–243, January, 1991. 相似文献
17.
This paper presents a few novel results, and collects together what is known and conjectured about the branching graph of a polyhex. 相似文献
18.
Ivan Nunes da Silva Wagner Caradori do AmaralLucia Valeria de Arruda 《Applied Mathematical Modelling》2007
This paper presents an efficient approach based on recurrent neural network for solving nonlinear optimization. More specifically, a modified Hopfield network is developed and its internal parameters are computed using the valid subspace technique. These parameters guarantee the convergence of the network to the equilibrium points that represent an optimal feasible solution. The main advantage of the developed network is that it treats optimization and constraint terms in different stages with no interference with each other. Moreover, the proposed approach does not require specification of penalty and weighting parameters for its initialization. A study of the modified Hopfield model is also developed to analyze its stability and convergence. Simulation results are provided to demonstrate the performance of the proposed neural network. 相似文献
19.
L. S. Vasil'ev F. E. Surzhikov O. G. Azarevich V. S. Bogdanov V. A. Dorokhov 《Russian Chemical Bulletin》1994,43(8):1431-1432
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1510–1511, August, 1994. 相似文献
20.
The primary resource for quantum computation is Hilbert-space dimension. Whereas Hilbert space itself is an abstract construction, the number of dimensions available to a system is a physical quantity that requires physical resources. Avoiding a demand for an exponential amount of these resources places a fundamental constraint on the systems that are suitable for scalable quantum computation. To be scalable, the effective number of degrees of freedom in the computer must grow nearly linearly with the number of qubits in an equivalent qubit-based quantum computer. 相似文献