Центральная Научная Библиотека УрО РАН

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   Г 15

    Галашев, А. Е.
    Компьютерное моделирование абсорбции молекул СO2 кластером воды. 1. Устойчивость [] = Computer simulation of the absorption of CO2 molecules by water cluster. Part 1. The stability / А. Е. Галашев, О. Р. Рахманова, В. Н. Чуканов // Коллоидный журнал. - 2005. - Т. 67, N 3. - 308-314: риc. - Библиогр: с. 314 (20 назв.) . - ISSN 0023-2912

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕ -- АДСОРБЦИИ МОЛЕКУЛ СO2 -- КЛАСТЕРЫ ВОДЫ -- МОЛЕКУЛЯРНАЯ ДИНАМИКА -- УСТОЙЧИВОСТЬ -- ТЕРМИЧЕСКИЕ ВОЗМУЩЕНИЯ -- МЕХАНИЧЕСКИЕ ВОЗМУЩЕНИЯ -- ДИЭЛЕКТРИЧЕСКИЕ ВОЗМУЩЕНИЯ -- метастабильные состояния -- КЛАСТЕРЫ (СO2)i(H2O)10 -- МОДЕЛИРОВАНИЕ КОМПЬЮТЕРНОЕ -- ВОДЫ КЛАСТЕРЫ -- ДИНАМИКА МОЛЕКУЛЯРНАЯ -- ВОЗМУЩЕНИЯ ТЕРМИЧЕСКИЕ -- ВОЗМУЩЕНИЯ МЕХАНИЧЕСКИЕ -- ВОЗМУЩЕНИЯ ДИЭЛЕКТРИЧЕСКИЕ
Аннотация: Методом молекулярной динамики моделируются кластеры (СO2)i(H2O)10 с кинетической энергией, соответствующей температуре 233К. Изучена устойчивость этих кластеров по отношению к термическим, механическим, диэлектрическим возмущениям, а также по отношению к абсорбции молекул CO2. Показано, что кластер, состоящий из 10 молекул воды,остается термодинамически устойчивым, если он захватывает одну или две молекулы CO2. Кластеры абсолютно неустойчивы, когда i больше или равно 3, меньше или равно 9. Метастабильное состояние кластеров достигается при i больше 9.

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   Г 15

    Галашев, А. Е.
    Компьютерное моделирование абсорбции молекул СO2 кластером воды. 2. Микроструктура [] = Computer Simulation of the Absorption of CO2 Molecules by Water Cluster: 2. The Microstructure / А. Е. Галашев, О. Р. Рахманова, В. Н. Чуканов // Коллоидный журнал. - 2005. - Т. 67, N 3. - 315-321: риc. - Библиогр: с. 321 (16 назв.) . - ISSN 0023-2912

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕ -- АДСОРБЦИИ МОЛЕКУЛ СO2 -- КЛАСТЕРЫ ВОДЫ -- МОЛЕКУЛЯРНАЯ ДИНАМИКА -- КЛАСТЕРЫ (СO2)i(H2O)10 -- МОДЕЛЬ ТIP4P -- МЕТОД СТАТИСТИЧЕСКОЙ ГЕОМЕТРИИ -- ТЕТРАЭДР -- МНОГОГРАННИКИ ВОРОНОГО -- МОДЕЛИРОВАНИЕ КОМПЬЮТЕРНОЕ -- ВОДЫ КЛАСТЕРЫ -- ВОРОНОГО МНОГОГРАННИКИ
Аннотация: Методом молекулярной динамики с использованием усовершенствованной модели TIP4P воды проведено моделирование абсорбции кластером(H2O)10 молекул CO2. Детальная структура кластеров (СO2)i(H2O)10, где i больше или равно 0, меньше или равно 11, анализируется методом статистической геометрии, основанном на построении многогранников Вороного. Полученные распределения геометрических элементов многогранников указывают на значительное изменение структуры кластера уже после абсорбции одной молекулы CO2. Близкую к идеальному тетраэдру несферичность показывают многогранники, характеризующие структуру неустойчивых кластеров воды, поглотивших 6 и 7 молекул CO2. Линейная молекула CO2 стремится ориентироваться в кластеретаким образом, чтобы средний угол, образуемый ею и перманентными дипольными моментами молекул воды, составлял около 30 градусов.

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   Г 15

    Галашев, А. Е.
    Компьютерное моделирование абсорбции молекул СO2 кластером воды. 3. Динамические и диэлектрические свойства [] = Computer Simulation of the Absorption of CO2 Molecules by Water Cluster: 3. Dynamic and Dielectric Properties / А. Е. Галашев, О. Р. Рахманова, В. Н. Чуканов // Коллоидный журнал. - 2005. - Т. 67, N 3. - 322-327: риc. - Библиогр: с. 327 (26 назв.) . - ISSN 0023-2912

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕ -- АДСОРБЦИИ МОЛЕКУЛ СO2 -- КЛАСТЕРЫ ВОДЫ -- КЛАСТЕРЫ (СO2)i(H2O)10 -- ДИНАМИЧЕСКИЕ СВОЙСТВА -- ДИЭЛЕКТРИЧЕСКИЕ СВОЙСТВА -- КОЭФФИЦИЕНТЫ САМОДИФФУЗИИ -- ИК-СПЕКТРЫ -- ЧАСТОТНО-ЗАВИСИМАЯ ДИЭЛЕКТРИЧЕСКАЯ ПРОНИЦАЕМОСТЬ -- МОДЕЛИРОВАНИЕ КОМПЬЮТЕРНОЕ -- ВОДЫ КЛАСТЕРЫ -- СВОЙСТВА ДИНАМИЧЕСКИЕ -- СВОЙСТВА ДИЭЛЕКТРИЧЕСКИЕ
Аннотация: Рассчитаны автокорреляционные функции трансляционных и угловых скоростей молекул H2O и CO2 в генерированных методом молекулярной динамики кластерах (CO2)i(H2O)10 и их частотные спектры. Определены коэффициенты самодиффузии молекул в кластерах. Полученные ИК-спектры и частично зависимая диэлектрическая проницаемость кластеров указывают на усиление абсорбции этими агрегатами тепловогоизлучения Земли при увеличении в них числа молекул CO2.Диэлектрические потери в этих кластерах также растут с увеличением числа i.

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   S 34

    Schmelzer, J. W. P.
    Classical and generalized Gibbs' approaches and the work of critical cluster formation in nucleation theory [Electronic resource] / J. W. P. Schmelzer, G. Sh. Boltachev, V. G. Baidakov // Journal of Chemical Physics. - 2006. - Vol. 124, № 19. - P194503/1-194503/18

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CLUSTERS
Аннотация: In the theoretical interpretation of the kinetics of first-order phase transitions, thermodynamic concepts developed long ago by Gibbs are widely employed giving some basic qualitative insights into these processes. However, from a quantitative point of view, the results of such analysis, based on the classical Gibbs approach and involving in addition the capillarity approximation, are often not satisfactory. Some progress can be reached here by the van der Waals and more advanced density functional methods of description of thermodynamically heterogeneous systems having, however, its limitations in application to the interpretation of experimental data as well. Moreover, both mentioned theories—Gibbs’ and density functional approaches—lead to partly contradicting each other’s results. As shown in preceding papers, by generalizing Gibbs’ approach, existing deficiencies and internal contradictions of these two well-established theories can be removed and a new generally applicable tool for the interpretation of phase formation processes can be developed. In the present analysis, a comparative analysis of the basic assumptions and predictions of the classical and the generalized Gibbs approaches is given. It is shown, in particular, that—interpreted in terms of the generalized Gibbs approach—the critical cluster as determined via the classical Gibbs approach corresponds not to a saddle but to a ridge point of the appropriate thermodynamic potential hypersurface. By this reason, the classical Gibbs approach (involving the classical capillarity approximation) overestimates as a rule the work of critical cluster formation in nucleation theory and, in general, considerably.

\\\\Expert2\\NBO\\Journal of Chemical Physics\\2006, v.124, p.194503.pdf
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   G 15

    Galashev, A. E.
    Computer investigation of the structure of Si73 clusters surrounded by hydrogen [Текст] / A. E. Galashev, I. A. Izmodenov // Glass Physics and Chemistry. - 2008. - Vol. 34, № 2. - С. 173-181

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
HYDROGEN
Аннотация: The stabilization of the structure of Si73 clusters that are surrounded by 60 hydrogen atoms and subjected to seventeenfold stepwise heating from 35 to 1560 K (in steps of ?90 K) is investigated using the molecular dynamics method. The analysis is performed for clusters of three types, i.e., a particle assembled from an icosahedron and a fullerene, a nanocrystal, and a particle with a random atomic packing. In all cases, an increase in the temperature in the course of heating is accompanied by evaporation of a Si atom from the clusters and an increase in the size of silicon particles. The temperature of detachment of Si atoms from clusters is lowest for the cluster with a random atomic packing and highest for the nanocrystal. The nanoassembled particle has the most stable number (close to four) of Si-Si bonds per atom over the entire temperature range 35 ? T ? 1560 K. For each type of Si73 clusters, the mean length of the Si-Si bond decreases with an increase in the temperature. According to the radial distribution functions, the Si73 clusters have different structures even at the temperature T = 1560 K. The distributions of bond angles reflect the presence of fourfold symmetry elements in the nanoassembled cluster and the nanocrystal. The relative depth of “penetration” of hydrogen atoms into the cluster is largest for the nanocrystal and smallest for the nanoassembled nanoparticle. The largest number of hydrogen atoms is “adsorbed” on the particle with a random atomic packing.

\\\\Expert2\\NBO\\Glass Physics and Chemistry\\2008, v. 34, N 2, p.173.pdf
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   N 89

    Novruzov, A. N.
    Computer study of the absorption of ethane by aqueous ultradispersed medium: IR spectra [Текст] / A. N. Novruzov, O. R. Rakhmanova, A. E. Galashev // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2008. - Vol. 70, № 1. - С. 55-63

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
IR SPECTRA
Аннотация: Absorption of ethane molecules by water clusters containing 10–20 molecules is studied by the molecular dynamics method. The (H2O) n (I), C2H6(H2O) n (II), and (C2H6)2(H2O) n (III) cluster systems are composed on the basis of specific statistical weights. Spectral characteristics of system and single clusters are determined in the frequency range of 0 меньше либо равно омега меньше либо равно 1000 cm в степени -1. In this frequency range, both real and imaginary parts of dielectric permittivity decrease monotonically after the absorption of C2H6 molecules by an aqueous ultradispersed system. Integral coefficient of IR absorption increases, while average (over frequency) reflection coefficient decreases after the absorption of ethane molecules. The intensity of IR scattering by the systems of clusters containing C2H6 molecules lowers. Maximal values of radiation power for water clusters with various sizes are balanced with the capture of ethane molecules by the clusters, whereas oscillations in the size dependence of the density of electrons that are active with respect to IR radiation decrease.

\\\\Expert2\\NBO\\Colloid Journal\\2008, V.70, N 1, 55.pdf
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   N 89

    Novruzova, O. A.
    IR spectra of aqueous disperse systems adsorbed atmospheric gases: 1. Nitrogen [Текст] / O. A. Novruzova, A. A. Galasheva, A. E. Galashev // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2007. - Vol. 69, № 4. - С. 474-482

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
IR SPECTRA
Аннотация: Spectral characteristics of (H2O) i , N2(H2O) i , and (N2)2(H2O) i cluster systems, where 10 меньше либо равно i меньше либо равно 50, are studied in the 0 меньше либо равно эпсилон меньше либо равно 3500 cm в степени -1 frequency range with the molecular dynamics method on the basis of a flexible molecule model. After nitrogen is captured by an aqueous disperse system, the absorption of the IR radiation by this system increases owing to the enhancement of intramolecular vibrations. In general, the reflection of the outer IR radiation by nitrated aqueous disperse systems is attenuated; however, when the nitrogen concentration increases twofold, there is a tendency toward an increase in the fraction of reflected radiation. As the nitrogen concentration in a system of water clusters rises, the power of radiation emitted by the system increases significantly and the number of electrons interacting with the outer IR radiation decreases.

\\\\Expert2\\NBO\\Colloid Journal\\2007, V.69, N4,474.pdf
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   A 10


    A computer study of the absorption of infrared radiation by systems of molecular clusters [Текст] / A. N. Novruzov, V. N. Chukanov, O. R. Rakhmanova, A. E. Galashev // High Temperature. - 2006. - Vol. 44, № 6. - С. 932-940

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
MOLECULAR CLASTERS
Аннотация: The method of molecular dynamics is used to investigate the process of absorption of N₂O and CH₄ molecules by water clusters and to determine the frequency spectra of permittivity for systems consisting of clusters mixed in different ratios, namely, (H₂O)_n, (N₂O)_i(H₂O)₁₀, and (CH₄)_i(H₂O)₁₀. IR-radiation absorption spectra for these systems are calculated and analyzed; the radiation power scattered by these systems and the tangent of dielectric loss angle are determined. The inclusion of anharmonicity of phonon oscillation makes it possible to explain the origin of characteristic frequencies appearing in IR spectra of mixtures of cluster systems. The capture of molecules of greenhouse gases by an ultradisperse aqueous medium affects the ability of this medium to absorb terrestrial radiation, i.e., reduces the greenhouse effect.

\\\\Expert2\\NBO\\High Temperature\\2006, v.44, p.932.pdf
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   G 15

    Galashev, A. E.
    Dielectric characteristics of O2(H2O)i and (O2)2(H2O)i clusters. Computer-aided experiment [Текст] / A. E. Galashev, V. N. Chukanov, O. A. Galasheva // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2006. - Vol. 68, № 2. - С. 131-136

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
DIELECTRIC CONSTANT
Аннотация: Absorption of oxygen molecules by water clusters with sizes of 10 меньше либо равно i меньше либо равно 50 is studied by the molecular dynamics method using the modified TIP4P model. It is revealed that the total dipole moment of the clusters nonmonotonically increases with their sizes. Absorption of O2 molecules tends to raise the static permittivity of the ultradispersed medium formed by the clusters. The real and imaginary parts of the permittivity of water clusters with absorbed O2 molecules are aperiodic functions of frequency. The permittivity components turn out to be nonmonotonic functions of cluster sizes. The IR absorption and reflectance spectra are calculated for clusters of pure water and aggregates with absorbed O2 molecules. After the addition of oxygen molecules, the absorption coefficient of the clusters decreases, while the reflection coefficient increases. It is concluded that the capture of oxygen molecules by atmospheric moisture may reduce the greenhouse effect.

\\\\Expert2\\NBO\\Colloid Journal\\2006, V.68, N2,131.pdf
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10.

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   G 15

    Galashev, A. E.
    Computer Simulation of the Stability of Water Clusters Containing Nitrogen Oxide Molecules [Текст] / A. E. Galashev, V. N. Chukanov // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2004. - Vol. 66, № 5. - С. 523-530

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
WATER CLUSTERS
Аннотация: The stability of water clusters containing nitrogen oxide molecules is studied by the molecular dynamics method. The composition and size of thermodynamically stable heteroclusters are determined. The inclusion of two molecules of nitrogen oxide into aggregates containing seven or more water molecule increases the cluster stability. The correlation between the stability of heteroclusters and the ratio of self-diffusion coefficients of molecules of different kinds is observed. The real part of the cluster permittivity is maximal in the vicinity of the frequency of 200 cm–1. The inclusion of nitrogen oxide molecules into water clusters increases the characteristic frequency of dielectric relaxation. In general, heteroclusters are more stable with respect to perturbations caused by an external electric field than pure clusters with the same number of water molecules. The clusterization of water vapors accompanied by absorption of polar molecules of impurity favors a decrease in the greenhouse effect.

\\\\Expert2\\NBO\\Colloid Journal\\2004, V.66, N5,523.pdf
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11.

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   G 15

    Galashev, A. E.
    Melting of the lead cluster in a molecular-dynamic model [] / A. E. Galashev // Surface (Russia). - 1998. - N11. - С. 68-75

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
MELTING OF CLUSTERS -- CLUSTERS LEAD -- MODEL MOLECULAR-DYNAMIC

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12.

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   G 15

    Galashev, A. E.
    Surface Tension and Structure of Crystalline Lead Cluster in the Molecular-Dynamics Model [] / A. E. Galashev // Crystallography Reports. - 1999. - V.44, N2. - С. 203-208

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
TENSION SURFACE -- STRUCTURE OF CLUSTERS -- CLUSTERS CRYSTALLINE -- CLUSTERS LEAD -- MODEL MOLECULAR-DYNAMICS
Аннотация: The geometrical and physical properties of a Pb-201 cluster in which the initial atomic packing corresponded to an extended Pb crystal has been studied by the molecular-dynamics methods. The surface tension of a microcrystal was calculated by the modified relationships of the drop theory with the use of the radial profiles of the normal and tangential pressure-tenser components determined by the method of radial profiles. The structure of a crystalline lead cluster was studied in the temperature range determined by the limit of its kinetic stability

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13.

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   G 15

    Galashev, A. E.
    Atomic dynamics and the size of metal clusters [] : a computer experiment / A. E. Galashev // Surface (Russia). - 1997. - N2. - С. 5-13

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
DYNAMICS ATOMIC -- CLUSTERS METAL -- Na -- Al -- Pb -- CRYSTAL
Аннотация: A computer study of atomic dynamics of metal clusters Na229, Al201 and Pb201 whose intial packing corresponded to extended crystals was carried out. The change of mobility in the radial direction of clusters was inverstigated. A reduction in lattice parameters of clusters Al201, Pb201 and some increase of the size of cluster Na229 have been found

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14.

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   G 15

    Galashev, A. E.
    Application of Molecular Dynamic Simulation of Water Clusters with CO and CO2 Molecules to Binary Nucleation Problems / A. E. Galashev, V. N. Chukanov, G. I. Pozharskaya // Journal of Structural Chemistry. - 2002. - Vol. 43, № 3. - С. 449-457 : рис.

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
GLOBAL CLUSTER GEOMETRY OPTIMIZATION -- THERMODYNAMIC PROPERTIES -- CLUSTERS

\\\\Expert2\\NBO\\Journal of Structural Chemistry\\2002, V. 43, N 3, p.449.pdf
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15.

Инвентарный номер: нет.

   G 15

    Galashev, A. E.
    Molecular dynamics calculation of spectral characteristics of water clusters in the presence of ozone molecules and chlorine ions / A. E. Galashev, O. R. Rakhmanova, O. A. Novruzova // Russian Journal of General Chemistry. - 2009. - Vol. 79, № 9. - С. 1765-1772

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CHARACTERISTICS SPECTRAL -- METHOD MOLECULAR DYNAMICS -- CLUSTER

\\\\Expert2\\NBO\\Russian Journal of General Chemistry\\2009, V. 79, N 9, p.1765.pdf
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16.

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   G 15

    Galashev, A. E.
    IR spectra of water clusters with captured ethane molecules: Computer simulation / A. E. Galashev, A. N. Novruzov // Russian Journal of General Chemistry. - 2008. - Vol. 78, № 1. - С. 26-34

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
ETHANE MOLECULES -- MONODISPERSE AQUEOUS -- CLUSTER

\\\\Expert2\\NBO\\Russian Journal of General Chemistry\\2008, V. 78, N 1, p.26.pdf
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17.

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   G 15

    Galashev, A. E.
    Computer Simulation of the Absorption of CO2 Molecules by Water Cluster: 3. Dynamic and Dielectric Properties / A. E. Galashev, O. R. Rakhmanova, V. N. Chukanov // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2005. - Vol. 67, № 3. - С. 285-290

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
FUNCTIONS AUTOCORRELATION -- CLUSTERS -- MOLECULAR DYNAMICS METHOD

\\\\Expert2\\NBO\\Colloid Journal\\2005, V.67, N3,285.pdf
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18.

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   G 15

    Galashev, A. E.
    Computer Simulation of the Absorption of CO2 Molecules by Water Cluster: 1. The Stability / A. E. Galashev, O. R. Rakhmanova, V. N. Chukanov // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2005. - Vol. 67, № 3. - С. 271-277

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CLUSTERS -- MOLECULAR DYNAMICS METHOD -- DIELECTRIC PERTURBATIONS

\\\\Expert2\\NBO\\Colloid Journal\\2005, V.67, N3,271.pdf
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19.

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   G 15

    Galashev, A. E.
    Computer Simulation of the Absorption of CO2 Molecules by Water Cluster: 2. The Microstructure / A. E. Galashev, O. R. Rakhmanova, V. N. Chukanov // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2005. - Vol. 67, № 3. - С. 278-284

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
MOLECULAR DYNAMICS METHOD -- CLUSTERS -- VORONOI POLYHEDRA

\\\\Expert2\\NBO\\Colloid Journal\\2005, V.67, N3,278.pdf
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20.

Инвентарный номер: нет.

   B 16

    Baidakov, V. G.
    On two approaches to determination of the nucleation rate of a new phase in computer experiments / V. G. Baidakov, A. O. Tipeev // Thermochimica Acta. - 2011. - Vol.522, №1-2. - С. 14-19

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
HOMOGENEOUS NUCLEATION -- MOLECULAR DYNAMICS -- METASTABLE SYSTEMS
Аннотация: The present paper gives a comparative evaluation of two approaches to the determination of the homogeneous nucleation rate in molecular dynamics computer experiments, viz. the methods of the mean lifetime of a metastable system and the mean time of the first passage to a cluster of a prescribed size. The crystal nucleation rate in a supercooled Lennard–Jones liquid has been determined in molecular dynamics simulation as a function of pressure at a reduced temperature T* = 0.55. The results of simulation have been compared with classical homogeneous nucleation theory. Good agreement between theory and the results of computer simulation has been found

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21.

Инвентарный номер: нет.

   B 16

    Baidakov, V. G.
    Comparison of Different Approaches to the Determination of the Work of Critical Cluster Formation / V. G. Baidakov, G. Sh. Boltachev, J. W. P. Schmelzer // Journal of Colloid and Interface Sience. - 2000. - Vol. 231, № 2. - С. 312-321

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CRITICAL CLUSTER -- GIBBS' METHOD -- NUCLEATION RATES
Аннотация: A comparative analysis of the results of determination of the work of critical cluster formation in nucleation theory for three different methods of evaluation—Gibbs' method, the van der Waals-Cahn and Hilliard, and a newly developed modified Gibbs' approach—is given. As a model system for comparison, regular solutions are chosen. In addition to the work of critical cluster formation, the composition of the critical clusters, their characteristic sizes and the values of the surface tension are determined in dependence on the initial supersaturation in the system or, equivalently, on the size of the critical clusters. It is found, in particular, that, for regular solutions, Tolman's equation cannot serve as a first approximation for the description of the curvature dependence of the surface tension even for large cluster sizes and an alternative formula is developed. It is shown that the latter two mentioned methods of determination of the work of critical cluster formation (the van der Waals-Cahn and Hilliard and the modified Gibbs' approach) lead—at least for the model system considered—to qualitatively and partly quantitatively equivalent results. Nevertheless, differences remain which may lead to quantitative deviations when applied to the determination of the steady-state nucleation rates. The possible origin of such deviations is discussed and some further directions of analysis are anticipated

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22.

Инвентарный номер: нет.

   S 34

    Schmelzer, J. W. P.
    Comment on “Multicomponent nucleation: Thermodynamically consistent description of the nucleation work” / J. W. P. Schmelzer, V. G. Baidakov // Journal of Chemical Physics. - 2004. - Vol.121, №3. - С. 1644-1645

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
THERMODYNAMICALLY CONSISTENT -- NUCLEATIONS -- CRITICAL CLUSTER
Аннотация: In the above cited paper, Kashchiev extends the “thermodynamically consistent” description of nucleation work to phase formation processes in multicomponent systems. It is claimed that this approach is generally applicable widely independent on the kind of phase transformation considered. In contrast to this statement, it is shown in our Comment that Kashchiev’s approach is theoretically not well founded. It contains, in addition, a number of assumptions, which are not generally fulfilled. Because of this his method cannot give, in general, a satisfactory determination of the work of critical cluster formation in nucleation theory. An experimental example is given verifying our

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23.

Инвентарный номер: нет.

   S 34

    Schmelzer, J. W. P.
    On different possibilities of a thermodynamically consistent determination of the work of critical cluster formation in nucleation theory / J. W. P. Schmelzer, V. G. Baidakov // Journal of Chemical Physics. - 2003. - Vol.119, №20. - С. 10759-10763

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
THERMODYNAMIC PROPERTIES -- CLUSTERS -- NUCLEATION
Аннотация: In a recent paper [J. Chem. Phys. 118, 1837 (2003)], Kashchiev claimed to have developed a general thermodynamically consistent formula allowing one to describe correctly the work of critical cluster formation in one-component systems for a variety of cases of formation of gaseous, liquid, and solid phases. It is shown that most of the consequences drawn lack any substantiation

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24.

Инвентарный номер: нет.

   S 34

    Schmelzer, J. W. P.
    Kinetics of boiling in binary liquid–gas solutions: Comparison of different approaches / J. W. P. Schmelzer, V. G. Baidakov, G. Sh. Boltachev // Journal of Chemical Physics. - 2003. - Vol.119, №12. - С. 6166-6183

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CRITICAL CLUSTER -- GIBBS' METHOD -- VAN-DER-WAALS
Аннотация: A comparative analysis of the results of determination of the work of critical cluster formation in nucleation theory for three different methods of evaluation—Gibbs’ method (employing the capillarity approximation), the van der Waals–Cahn and Hilliard and a newly developed modified Gibbs’ approach—is given in application to phase formation in multicomponent systems. As an example, processes of boiling in binary liquid–gas solutions, in particular, in nitrogen–helium mixtures are investigated. In addition to the work of critical cluster formation, the bulk properties of the critical bubbles, their characteristic sizes and the values of the surface tension are determined in dependence on the initial supersaturation in the system or, equivalently, on the size of the critical clusters. It is shown that latter two mentioned methods (the van der Waals–Cahn and Hilliard and the modified Gibbs’ approach) lead, in the determination of the work of critical cluster formation, to qualitatively and widely even quantitatively equivalent results. As one of the more general consequences from the present analysis, it has been proven that the modified Gibbs’ approach represents a highly effective tool for the determination of the work of formation of clusters or bubbles of critical sizes not only for one-component and quasibinary systems, discussed earlier, but for phase formation in multicomponent systems of, in general, arbitrary numbers of components as well. It is shown that the modified Gibbs’ approach is preferable as compared with Gibbs’ original treatment not only due to its advantages with respect to an appropriate determination of the properties of clusters of critical sizes, but also from general theoretical considerations. In the limit of large sizes of the critical clusters, both approaches—Gibbs’ original treatment and the modified or generalized Gibbs’ approach—lead to equivalent results

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25.

Инвентарный номер: нет.

   S 34

    Schmelzer, J. W. P.
    Kinetics of Condensation and Boiling: Comparison of Different Approaches / J. W. P. Schmelzer, V. G. Baidakov // Journal of Physical Chemistry B. - 2001. - Vol.105, №47. - С. 11595-11604

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CRITICAL CLUSTER -- GIBBS' METHOD -- VAN-DER-WAALS METHOD -- HILLIARD METHOD
Аннотация: A comparative analysis of the results of determination of the work of critical cluster formation in nucleation theory for three different methods of evaluationGibbs' method (employing the capillarity approximation), the van der Waals−Cahn and Hilliard method, and a newly developed modified Gibbs approachis given. As a particular application, the processes of condensation and boiling in one-component fluids are analyzed. As a model system for comparison, van der Waals fluids are chosen. In addition to the work of critical cluster formation, the bulk properties of the critical clusters (drops or bubbles), their characteristic sizes, and the values of the surface tension are determined in dependence on the initial supersaturation in the system or, equivalently, on the size of the critical clusters. It is shown that latter two mentioned methods of determination of the work of critical cluster formation (the van der Waals−Cahn & Hilliard and the modified Gibbs approach) leadat least for the model system consideredto qualitatively and partly quantitatively equivalent results. Nevertheless, differences remain which may lead to quantitative deviations when applied to the determination of the steady-state nucleation rates and further basic characteristics of nucleation-growth processes. The possible origin of such deviations is discussed, and some further directions of analysis are anticipated

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26.

Инвентарный номер: нет.

   P 80

    Polukhin, V. A.
    Effect of the character of the (Ni, Pd) cluster/graphene interatomic bonds on the thermosize effects and structural-isomeric transitions [Электронный ресурс] / V. A. Polukhin, E. D. Kurbanova, A. E. Galashev // RUSSIAN METALLURGY. - 2012. - №8. - P696-704

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
COMPREHENSIVE ANALYSIS -- HEATING CONDITIONS -- INTERATOMIC BONDS
Аннотация: The thermal evolution of nanoclusters is studied by molecular dynamics simulation to analyze the nucleation and kinetics of the kinetic processes that determine the basic factors of the onset of premelting and the loss of thermal stability of a two-dimensional system of transition-metal (Pd, Ni) nanoclusters located on a graphene substrate. A comprehensive analysis reveals the effect of the initial structural characteristics of nanoclusters, the heating conditions, and the kinetic factors during thermally activated diffusion on the nanostructuring in the thermal evolution of the nanoclusters. This evolution includes the following stages: isomerization, quasi-melting, and the decomposition of a given regular structure; it is classified as an order-disorder transition and as an analog of phase transitions in macroscopic systems on the nanoscale

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27.

Инвентарный номер: нет.

   G 15

    Galashev, A. E.
    Spectral characteristics of water clusters in the presence of nitrate ions [Электронный ресурс] / A. E. Galashev // Colloid Journal (Translation of Kolloidnyi Zhurnal). - 2012. - Vol.74, №6. - P655-662

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
DIELECTRIC PERMITTIVITIES -- FLEXIBLE MOLECULES -- IR ABSORPTION COEFFICIENT
Аннотация: Nitrate ion adsorption by water clusters is studied using the molecular dynamics method combined with a polarizable model of flexible molecules. It is established that successive addition of one to six NO 3 - ions to an (H2O)50 cluster decreases the averaged electrical potential related to the center of masses of water molecules. The (H2O)50 cluster retains its thermodynamic stability, provided that no more than three nitrate ions are added to it. After NO 3 - ions are adsorbed, the real and imaginary components of the dielectric permittivity and the intensity of the Raman spectrum decrease, while the intensity of the IR absorption spectrum increases. Moreover, ion adsorption by the water cluster reduces the IR absorption coefficient and refractive index

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28.

Инвентарный номер: нет.

   G 15

    Galashev, A. E.
    Computer simulation of the cluster destruction of stratospheric ozone by bromine [Электронный ресурс] / A. E. Galashev, O. R. Rakhmanova // Chinese Physics B . - 2012. - Vol. 21, №11. - P113602

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
BROMINE IONS -- INFRARED AND RAMAN SPECTRA -- WATER CLUSTERS
Аннотация: The interaction of (Br -) iH 2O) 50-i, 0 ≤ i ≤ 6 clusters with oxygen and ozone molecules is investigated by the method of molecular dynamics simulation. The ozone molecules as well as the bromine ions do not leave the cluster during the calculation of 25 ps. The ability of the cluster containing molecular oxygen to absorb the infrared (IR) radiation is reduced in the frequency range of 0 ≤ ω ≤ 3500 cm -1 when the number of the bromine ions in the cluster grows. The intensity of the Raman spectrum is not changed significantly when the Br - ions are added to the ozone-containing system. The power of the emitted IR radiation is increased when the number of bromine ions grows in the oxygen-containing system. The data obtained in this study on the IR and the Raman spectra of the water clusters that contain ozone, oxygen, and Br - can be used to develop an investigation of the mechanisms of ozone depletion

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29.

Инвентарный номер: нет.

   G 15

    Galashev, A. E.
    Physical properties of silver-coated silica clusters: A computer experiment [Электронный ресурс] / A. E. Galashev // Journal of Surface Investigation . - 2012. - Vol.6, №4. - P623-630

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
ELECTROMAGNETIC FIELDS -- MOLECULAR DYNAMICS -- SILICA
Аннотация: The effect on the physical properties of a silica cluster after silver coating has been studied by the molecular dynamics method. It has been established that silver atoms make a sphere-like cluster shape, increase mechanical stability and give a stable positive value of the surface tension. They increase the number of electrons able to interact with the electromagnetic field, and, hence, enhance the efficiency of thermal radiation transfer by clusters

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30.

Инвентарный номер: нет.

   G 15

    Galashev, A. E.
    Molecular dynamics simulation of adsorption of ozone and nitrate ions by water clusters [Электронный ресурс] / A. E. Galashev // High Temperature. - 2012. - Vol.50, №2. - P204-213

ББК 53
Рубрики: ФИЗИКА
Кл.слова (ненормированные):
CO-ADSORPTION -- DISPERSE SYSTEMS -- NITRATE IONS
Аннотация: Coadsorption of ozone molecules and nitrate ions by water clusters was studied by the molecular dynamics technique. The maximum value of an average O-H⋯O bond length in a water carcass is realized at the minimum specific number of such bonds when the ratio of adsorbed ozone molecules to nitrate ions captured by a cluster is two. IR absorption and reflection spectra were reshaped significantly, and new peaks appeared at Raman spectra due to the addition of ozone and nitrate ions to the disperse water system. After ozone and nitrate ions were captured, the average (in frequency) IR reflection coefficient of the water disperse system increased drastically and the absorption coefficient fell

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1-30 31-60 61-76

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