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排序方式: 共有171条查询结果,搜索用时 15 毫秒
1.
Sergio Albeverio Volodymyr Koshmanenko Mykola Pratsiovytyi Grygoriy Torbin 《Positivity》2006,10(1):39-49
We introduce the conflict interaction with two positions between a couple of image probability measures and consider the associated
dynamical system. We prove the existence of invariant limiting measures and find the criteria for these measures to be a pure
point, absolutely continuous, or singular cotinuous as well as to have any topological type and arbitary Hausdorff dimension. 相似文献
2.
Roman P. Pogorilyi Inna V. Melnyk Yuriy L. Zub Guliam A. Seisenbaeva Vadim G. Kessler Mykola M. Shcherbatyik Aljoša Košak Aleksandra Lobnik 《Journal of Sol-Gel Science and Technology》2013,68(3):447-454
The surface of magnetite nanoparticles was coated with functional polysiloxane layers using reaction of hydrolytic copolycondensation of tetraethoxysilane and 3-aminopropyltriethoxysilane (or N-[3-trimethoxysilylpropyl]ethylendiamine), and also that of tetraethoxysilane, 3-aminopropyltriethoxysilane and methyltriethoxysilane (or n-propyltriethoxysilane). It was shown that these functionalized magnetically controllable particles (about 60–150 nm in size as aggregates), as opposed to magnetite, adsorb urease well from aqueous solutions (up to 1 g/g), and that the level of residual activity of adsorbed layers is up to 84 % in the case of a bifunctional sample. It was established that the activity of immobilized urease is normally gradually reduced during storage of the samples, but in the case of ethylenediamine functional group is not decreased for 45 days. The synthesized samples are promising for use as magnetically directed biocatalysts. 相似文献
3.
A. Yu. Vasil’kov I. P. Suzdalev Yu. V. Maksimov L. N. Nikitin A. V. Naumkin S. S. Abramchuk E. M. Tolstopyatov P. N. Grakovich 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(6):985-991
A method for synthesizing iron-containing nanocomposite based on fibroporous polytetrafluoroethylene (PTFE) is described. Fibroporous PTFE obtained under the radiation of a CO2 laser on block PTFE is modified in supercritical carbon dioxide (sc CO2) to form micro- and nanoporous structures. Porous fluoropolymer is treated with a solution of bis(toluene)iron(0) obtained by metal-vapor synthesis (MVS). The composition and structure of iron-containing fluoropolymer is studied by transmission electron microscopy and X-ray photoelectron and Mössbauer spectroscopy. Fe nanoparticles with an average size of 9 nm, consisting of ~30% FeO and ~70% Fe3+, are registered in the sample. Fe0 nanoparticles are stabilized in fluoropolymer pores and are coated with nanoparticles of nonstoichiometric iron oxides that have superparamagnetic properties. 相似文献
4.
A. I. Aleksandrov I. A. Aleksandrov S. B. Zezin E. N. Degtyarev A. A. Dubinskiy S. S. Abramchuk A. I. Prokof’ev 《Russian Journal of Physical Chemistry B, Focus on Physics》2016,10(1):69-76
Superradiance induced by the rheological explosion of composites based on polystyrene, cobalt acetylacetonate, and/or 3,5-di-tert-butylcatechol has been investigated. The superradiance intensity is determined by solid-phase chemical reactions induced by the rheological explosion. EPR, X-ray diffraction, and electron microscopic characterization of stable products resulting from the rheological explosion in the polymer matrix has demonstrated that the superradiance intensity is related to the electronic properties and structure of two-spin intermediates, namely, radical pairs and organoelement biradicals. 相似文献
5.
Nazariy T. Pokhodylo Roman D. Savka Olga Ya. Shyyka Mykola D. Obushak 《Journal of heterocyclic chemistry》2020,57(7):2969-2976
The one-pot CuAAC synthesis of (1H-1,2,3-triazol-1-yl)methyl-1,3,4-oxadiazole and (1H-1,2,3-triazol-1-yl)methyl-1,2,4-oxadiazole derivatives via three-component reaction of consequent nucleophilic substitution of chlorine, with azide, and its further “click” reaction, with alkynes, in the presence of CuI was studied. The utility of newly synthesized 2-(azidomethyl)-1,3,4/1,2,4-oxadiazoles and chloromethyl-1,3,4/1,2,4-oxadiazole derivatives was explored, and their limitations were determined. Novel 5-([4-aryl-1H-1,2,3-triazol-1-yl]methyl)-3-(aryl)-1,2,4-oxadiazoles, 2-([4-aryl-1H-1,2,3-triazol-1-yl]methyl)-5-(aryl)-1,3,4-oxadiazoles were obtained in good yields. 相似文献
6.
Liliya Dubenska Olha Dushna Solomiya Pysarevska Mykola Blazheyevskiy 《Electroanalysis》2020,32(3):626-634
In present paper we described a new simple voltammetric method of determination of nefopam alkaloid and its metabolite – N‐oxide. N‐oxide of nefopam is reduced at the dropping mercury electrode (DME) and silver solid amalgam electrodes (AgSAE), which can effectively replace mercury and chemically modified electrodes. The reduction consists of two one‐electron stages each accompanied with one proton transfer. N‐oxide of nefopam can be obtained from nefopam substance by oxidation with potassium peroxymonosulfate. It was studied the effect of various factors on N‐oxide quantitative yield (pH, oxidation duration, reagents concentration) as well as on the reduction of N‐oxide at DME and p‐AgSAE (pH, the nature of background electrolyte, potential and time of accumulation). It was showed that the reduction current linearly increased with increasing of concentration of analgesic. Limit of quantiation is 10?6 mol L?1 at DME and 10?7 mol L?1 at p‐AgSAE. The developed method was applied for the analysis of commercial drug solution for injection “Nefopam” with recovery of 96.7 %, as well as for the spiked human urine samples. Excellent repeatability with a relative standard deviation below 5 % was achieved. 相似文献
7.
Direct and inverse problems for first-order in time linear evolution problems without initial conditions, i.e. related to
the unbounded time-intervals (−∞, 0] and
\mathbbR{\mathbb{R}}, are considered in the framework of Banach spaces. Some degenerate in time problems related to a bounded time-interval are
also considered.
The approach for solving the previous problems is related to both C
0-and Analytic Semigroup Theory. 相似文献
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