1,755 research outputs found
Rate of Convergence of Space Time Approximations for stochastic evolution equations
Stochastic evolution equations in Banach spaces with unbounded nonlinear
drift and diffusion operators driven by a finite dimensional Brownian motion
are considered. Under some regularity condition assumed for the solution, the
rate of convergence of various numerical approximations are estimated under
strong monotonicity and Lipschitz conditions. The abstract setting involves
general consistency conditions and is then applied to a class of quasilinear
stochastic PDEs of parabolic type.Comment: 33 page
Abelian groups as artinian or noetherian modules above endomorphism rings
The A and B Abellian groups, such that the Hom(A, B) homomorphism group is the Artin module over the ring of the B group endomorphism, are described. Description of the A and B group for which the Hom(A,B) group is the Artin module over the ring of the A group endomorphism is reduced to the case when the A group has no torsion and the B group is either a quasi-cyclic group or a divisible group without torsion. The A and B Abellian groups for which the Hom(A,B) group is the Neter module over the E(A) or E(B) ring are characterized. The research of arbitrary Abellian group with the link Neter ring of endomorphisms is reduced to the research of the group without torsion with the link Neter ring of endomorphisms. The research of the right Neter ring of endomorphisms remained uncompleted. The separable Abele groups without torsion with the link and right Neter rings of endomorphisms are described
A Design of a Material Assembly in Space-Time Generating and Storing Energy
The paper introduces a theoretical background of the mechanism of electromagnetic energy and power accumulation and its focusing in narrow pulses travelling along a transmission line with material parameters variable in 1D-space and time. This mechanism may be implemented due to a special material geometry- a distribution of two different dielectrics in a spatio-temporal checkerboard. We concentrate on the practically reasonable means to bring this mechanism into action in a device that may work both as energy generator and energy storage. The basic ideas discussed below appear to be fairly general; we have chosen their electromagnetic implementation as an excellent framework for the entire concept
Identification of antischistosomal leads by evaluating peroxides of beta-dicarbonyl compounds and their heteroanalogs : bridged 1,2,4,5-tetraoxanes and alphaperoxides, and beta,delta-triketones: tricyclic monoperoxides
Although antischistosomal properties of peroxides were studied in recent years, systematic structure-activity relationships have not been conducted. We evaluated the antischistosomal potential of 64 peroxides belonging to bridged 1,2,4,5-tetraoxanes, alphaperoxides and beta,delta-triketones. Thirty-nine compounds presented IC50 values > 15 microM on newly transformed schistosomula. Active drugs featured phenyl-, adamantane- or alkyl residues at the methylene bridge. Lower susceptibility was documented on adult schistosomes, with most hit compounds being tricyclic monoperoxides (IC50: 7.7-13.4 microM). A bridged 1,2,4,5-tetraoxane characterized by an adamantane residue showed the highest activity (IC50: 0.3 microM) on adult Schistosoma mansoni. Studies with hemin and heme supplemented medium indicated that antischistosomal activation of peroxides is not necessarily triggered by iron porphyrins. Two compounds (tricyclic monoperoxide; bridged 1,2,4,5-tetraoxane) revealed high worm burden reductions in the chronic (WBR: 75.4-82.8 %) but only moderate activity in the juvenile (WBR:18.9-43.1%) S. mansoni mouse model. Our results might serve as starting point for the preparation and evaluation of related derivative
The level of somatic health, sports specialization and qualification of an athlete as indicators of intermediate selection in the mixed martial arts
This article presents the results of experimental research to identify high-priority types of martial arts whose representatives successfully implement their skills in mixed martial arts, as well as the results of the study of somatic healt
Fast processing of data from Sneg-2MP experiment
The following subjects are covered: Basic stages during computer processing of data from Sneg-2MP instrument, basic modes during separation and fast processing (separation of data during satellite flight, separation of burst data segments, sampling and analysis of initial burst data segment). Experimental results obtained on the basis of fast processed data are reported
Electron energy relaxation under terahertz excitation in (Cd1−xZnx)3As2 Dirac semimetals
We demonstrate that measurements of the photo-electromagnetic effect using terahertz laser radiation provide an argument for the existence of highly conductive surface electron states with a spin texture in Dirac semimetals (Cd₁-xZnx)₃As
Mutual Fund Theorem for continuous time markets with random coefficients
We study the optimal investment problem for a continuous time incomplete
market model such that the risk-free rate, the appreciation rates and the
volatility of the stocks are all random; they are assumed to be independent
from the driving Brownian motion, and they are supposed to be currently
observable. It is shown that some weakened version of Mutual Fund Theorem holds
for this market for general class of utilities; more precisely, it is shown
that the supremum of expected utilities can be achieved on a sequence of
strategies with a certain distribution of risky assets that does not depend on
risk preferences described by different utilities.Comment: 17 page
Gas chromatographic-mass spectrometric analysis of high purity sulfur hexafluoride enriched with ³²S isotope
Методом хромато-масс-спектрометрии впервые исследован примесный состав высокочистого гексафторида серы, обогащенного изотопом ³²S. Для разделения примесей использовали адсорбционную капиллярную колонку GS-GasPro 60 м ´ 0.32 мм с модифицированным силикагелем и колонку 25 м × 0.26 мм, d f = 0.25 мкм с политриметилсилилпропином. Показано, что колонка GS-GasPro позволяет определять примеси веществ с невысокими молекулярными массами: от постоянных газов до пентана. При использовании колонки с политриметилсилилпропином возможно определение примесей с большими молекулярными массами и температурами кипения. Идентификацию примесей проводили сравнением экспериментальных масс-спектров с данными базы NIST. Идентифицировано 26 примесных веществ, из них 18 - впервые по сравнению с известными примесями в SF6 природного изотопного состава. Идентифицированными примесями являются: постоянные газы, диоксид углерода, предельные и непредельные углеводороды С₁-С₈, ароматические и фторсодержашие углеводороды. Количественное определение примесей проводили в режиме селективного ионного детектирования по наиболее интенсивным пикам их масс-спектров. В качестве образцов сравнения использовали аттестованную поверочную смесь на основе высокочистого гелия и градуировочные смеси, приготовленные объемно-манометрическим методом. Диапазон концентраций примесей в использованных смесях составлял 10⁻⁵-10⁻¹ % об. Приводятся результаты анализа реального образца ³²SF₆. Концентрации обнаруженных примесей составляет 9.2∙10⁻³-3∙10⁻⁶ % об. В наибольших концентрациях присутствуют азот и тетрафторид углерода - 9.2∙10⁻³ и 2.8∙10⁻³ % об. Пределы обнаружения примесей составляют 1∙10⁻⁵-5∙10⁻⁸ % об. Правильность определения примесей в ³²SF₆ подтверждали методом варьирования величины пробы. Показано, что систематические погрешности статистически незначимы по сравнению со случайными.The method of gas chromatography-mass spectrometry was used for the first time to investigate the impurity composition of high-purity sulfur hexafluoride enriched with ³²S isotope. For the separation of impurities an adsorption capillary column GS-GasPro of 60 m ´ 0.32 mm with a modified silica gel and a column of 25 m × 0.26 mm, d f = 0.25 microns with a poly trimethylsilyl propyne (PTMSP) were used. It was shown that GS-GasPro column allowed separating the impurity substances with low molecular weights - from permanent gases to pentane. When using the poly trimethylsilyl propyne (PTMSP) column, the determination of the impurities with higher molecular weights and boiling points were possible. The identification of impurities was performed by comparing the experimental mass spectra with a NIST data base. 26 impurity substances were identified, of which 18 - for the first time in comparison with the known SF₆ impurities in the natural isotopic composition. The following impurities were defined: permanent gases, carbon dioxide, saturated, unsaturated hydrocarbons C₁-C₈, aromatics, oxygenates and fluorinated hydrocarbons. The quantitative determination of impurities was performed using the selective ion mode detection of the most intense peaks in the mass spectra. As certified reference samples a reference mixture based on the high-purity helium and calibration mixtures were used. The range of impurity concentrations in the mixtures used was 10⁻⁵-10⁻¹ % vol. The results of the ³²SF6 analysis were presented. The concentrations of impurities in them were 9.2∙10⁻³-3∙10⁻⁶ % vol. Carbon tetrafluoride and nitrogen were present in the highest concentrations - 9.2∙10⁻³ and 2.8∙10⁻³ % vol. respectively. The detection limits of impurities were 1∙10⁻⁵-5∙10⁻⁸ % vol. The correctness of the determination of impurities in in ³²SF₆ was confirmed by varying the value of the sample. It was shown that the systematic errors were not statistically significant when compared with the random ones
Materials based on BIFEVOX and bismuth or iron simple oxides nanopowders
Received: 22.09.2017; accepted: 17.10.2017; published: 20.10.2017.Compositions of composite materials based on BIFEVOX and nanopowders of bismuth and iron oxides have been obtained. The absence of chemical interaction between the components has been proved, the total electrical conductivity of materials in the average temperature region has been determined. It has been shown that under the selected formation conditions, it has not yet been possible to achieve significant improvement of the functional characteristics of heterogeneous compositions in comparison with individual phases. However positive results on chemical and structural stability give way to further investigations.The work was partially supported by the Scholarship of the President (SP-3376.2016.1) and Russian Foundation for Basic Research (project No 17-53-04098)
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