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101.
The presented paper contains a suggestion and an analysis of a two-level preconditioner appropriate for unstructured meshes. The convergence analysis is done for H1-equivalent forms in the two-dimensional case; ways for generalization are discussed, too. The efficiency is demonstrated by numerical experiments. 相似文献
102.
A. A. Anikeev S. B. Viktorov S. A. Gubin 《Russian Journal of Physical Chemistry B, Focus on Physics》2014,8(1):56-60
A numerical modeling of the thermodynamic properties of a fluid is performed using the method of integral equations. The predictions are compared with the results of MC and MD simulations. The problem of stability of the numerical solution is examined. The methods for correcting the correlation functions and for estimating their uncertainties are proposed. 相似文献
103.
Anastasia V. Egorova Nikolai B. Viktorov Galina L. Starova Nataly I. Svintsitskaya Aleksandr V. Garabadziu Albina V. Dogadina 《Tetrahedron letters》2017,58(30):2997-3001
The boron trifluoride diethyl etherate catalyzed intramolecular cyclization of diethyl 2-(dialkoxyphosphorylethynyl)-2-arylaminomalonates afforded a series of novel 3-phosphonylated indoles, diethyl 2-[3-(dialkoxyphosphoryl)-1H-indol-2-yl]propanedioates. Decarboxylation of the latter compounds resulted in the formation of ethyl 2-[3-(dialkoxyphosphoryl)-1H-indol-2-yl]acetates. 相似文献
104.
S. I. Bityukov G. V. Borisov V. A. Dorofeev R. I. Dzhelyadin S. V. Golovkin M. V. Gritzuk A. S. Konstantinov V. P. Kubarovski N. Yu. Kul'man A. I. Kulyavtzev V. F. Kurshetzov L. G. Landsberg V. V. Lapin V. V. Molchanov V. A. Mukhin Yu. B. Novozhilov V. F. Obraztzov V. I. Solyanik V. A. Viktorov A. M. Zaitsev 《Zeitschrift fur Physik C Particles and Fields》1991,50(3):451-454
The radiative decayη′→π + π ? γ has been studied with the statistics of ?2000 events. Different ways of describingm ππ distribution are considered. It is shown that if the dominating contribution to this process is made by the decay channel η′→ργ, then the generally accepted ways of describing the ρ peak do not agree with experimental data. 相似文献
105.
Jitka Dupačová 《Annals of Operations Research》1991,30(1):199-214
Different approaches to statistical sensitivity analysis for optimal solutions of stochastic programs are discussed and compared. Possibilities of drawing conclusions about asymptotic behavior of estimated optimal solutions by means of stability properties of auxiliary randomly perturbed convex quadratic programs are indicated and illustrated on a numerical example. 相似文献
106.
I. V. Bodnar V. F. Gremenok I. A. Viktorov D. D. Krivolap 《Journal of Applied Spectroscopy》1998,65(6):996-999
Thin films of copper tellurogallate were obtained by the method of pulsed laser spraying. The structure of the films and the
parameters of the unit cell were determined by the x-ray method. It is shown that the films possess p-type conduction and
their resistivity decreases with an increase in the substrate temperature. From the transmission near the edge of the fundamental
absorption band a determination was made of the energy of interband transitions, crystalline cleavage, and spin-orbital splitting.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 6, pp. 946–949, November–December, 1998. 相似文献
107.
Jitka Dupačová 《Annals of Operations Research》1995,56(1):65-78
The contamination technique is presented as a flexible and relatively easily tractable tool to postoptimality analysis for scenario based multistage stochastic linear programs. It is promising especially in cases when the influence of additional or out-of-sample scenarios on the already solved problem is to be explored.Research supported in part by the Grant Agency of the Czech Republic under Grant No. 402/93/0631. 相似文献
108.
109.
New methods of flow injection analysis (FIA) neutralization titrations of phenothiazine derivatives in aqueous micellar medium of a cationic surfactant using potentiometric and spectrophotometric detection were proposed; titrations with a mixing gradient chamber and high-speed titrations were compared. The FIA titration method in non-aqueous media based on an official method of determination (titration with perchloric acid in anhydrous acetic acid) was also developed. Under optimized reaction conditions and flow-through parameters, the calibration range and equations, the sensitivity, and the repeatability of all methods were found and discussed. All titrations were assayed for medicinal forms. 相似文献
110.
Zrostlíková J Hajslová J Kovalczuk T Stĕpán R Poustka J 《Journal of AOAC International》2003,86(3):612-622
A simple liquid chromatography/mass spectrometry (LC/MS) approach for the determination of widely used representatives of polar/thermolabile pesticides in fruits was developed and validated. The group of pesticides comprised benzimidazoles and azoles (carbendazim, thiabendazole, imazalil, propiconazole, prochloraz, epoxiconazole, flusilazole, tebuconazole, bitertanol); N-methylcarbamates (carbaryl, carbofuran, methiocarb); and phenylureas and benzoylphenylureas (linuron, diflubenzuron, triflumuron, teflubenzuron, flufenoxuron). Matrixes (apple, apricot) were extracted with acetonitrile and crude extracts were cleaned up by solid-phase extraction (SPE) using either mixed cation exchange or hydrophilic lipophilic balance cartridges. LC separation of pesticides was performed on a reversed-phase column, Discovery C18. Electrospray ionization and ion trap MS/MS detection were applied. For most pesticides, overall recoveries ranged from 75 to 122%, and repeatability (as relative standard deviation) from 5 repetitive determinations of recovery ranged from 3 to 21%. Carbofuran was the only compound for which recovery was not satisfactory due to its loss in the SPE cleanup step. Limits of detection were 0.1-3 microg/kg for benzimidazole and azole fungicides and carbamate insecticides. For urea insecticides, detection limits were slightly higher (3-10 microg/kg). 相似文献