Physical Features of Binary Coulomb Crystals: Madelung Energy, Collective Modes and Phonon Heat Capacity

Density waves in the nature of those proposed by B. Lindblad are described by detailed mathematical analysis of collective modes in a disk-like stellar system. The treatment is centered around a hypothesis of quasi-stationary spiral structure. We examine (a) the mechanism for the maintenance of this spiral pattern, and (b) its consequences on the observable features of the galaxy.

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A photoelectron microscope study of surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152021 ◽

1989 ◽

Vol 47 ◽

pp. 10-11

Author(s):

W. Engel ◽

M. Kordesch ◽

A. M. Bradshaw ◽

E. Zeitler

Keyword(s):

Electron Microscopy ◽

High Pressure ◽

Field Strength ◽

Uv Light ◽

Physical Property ◽

Photon Flux ◽

Mercury Lamp ◽

Object Surface ◽

The Sixties ◽

Physical Features

Photoelectron microscopy is as old as electron microscopy itself. Electrons liberated from the object surface by photons are utilized to form an image that is a map of the object's emissivity. This physical property is a function of many parameters, some depending on the physical features of the objects and others on the conditions of the instrument rendering the image.The electron-optical situation is tricky, since the lateral resolution increases with the electric field strength at the object's surface. This, in turn, leads to small distances between the electrodes, restricting the photon flux that should be high for the sake of resolution.The electron-optical development came to fruition in the sixties. Figure 1a shows a typical photoelectron image of a polycrystalline tantalum sample irradiated by the UV light of a high-pressure mercury lamp.

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HEAT CAPACITY MEASUREMENTS ON THE DILUTED ISING SYSTEM Cs3CopZn1-pCl5

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19711359 ◽

1971 ◽

Vol 32 (C1) ◽

pp. C1-1008-C1-1009 ◽

Cited By ~ 3

Author(s):

E. LAGENDIJK ◽

W. J. HUISKAMP ◽

P. F. BONGERS

Keyword(s):

Heat Capacity ◽

Ising System ◽

Heat Capacity Measurements

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HEAT CAPACITY OF NEODYMIUM BELOW 10 K

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19786354 ◽

1978 ◽

Vol 39 (C6) ◽

pp. C6-794-C6-795 ◽

Cited By ~ 1

Author(s):

E. M. Forgan ◽

C. M. Muirhead

Keyword(s):

Heat Capacity

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COLLECTIVE MODES IN ARRAYS OF SUPERCONDUCTING BRIDGES

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19786265 ◽

1978 ◽

Vol 39 (C6) ◽

pp. C6-588-C6-590 ◽

Cited By ~ 2

Author(s):

S. N. Artemenko ◽

A. F. Volkov ◽

A. V. Zaitsev

Keyword(s):

Collective Modes

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TEMPERATURE-LINEAR TERM OF HEAT CAPACITY OF La-Ba-Cu-O AND La-Sr-Cu-O SYSTEMS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19888954 ◽

1988 ◽

Vol 49 (C8) ◽

pp. C8-2133-C8-2134

Author(s):

K. Kumagai ◽

Y. Nakamura ◽

I. Watanabe ◽

Y. Nakamichi ◽

H. Nakajima

Keyword(s):

Heat Capacity ◽

Linear Term

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THE MECHANISM OF RAISING AND QUANTIFICATION OF SPECIFIC HEAT FLUX AT BOILING OF NANOFLUIDS IN FREE CONVECTION CONDITIONS

Energy Technologies & Resource Saving ◽

10.33070/etars.3.2017.03 ◽

2017 ◽

pp. 25-34

Author(s):

V.N. Moraru

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Heat Capacity ◽

Specific Heat ◽

Chemical Properties ◽

Heating Surface ◽

Physical Models ◽

Superheated Liquid ◽

Two Phase ◽

Boiling Process

The results of our work and a number of foreign studies indicate that the sharp increase in the heat transfer parameters (specific heat flux q and heat transfer coefficient _) at the boiling of nanofluids as compared to the base liquid (water) is due not only and not so much to the increase of the thermal conductivity of the nanofluids, but an intensification of the boiling process caused by a change in the state of the heating surface, its topological and chemical properties (porosity, roughness, wettability). The latter leads to a change in the internal characteristics of the boiling process and the average temperature of the superheated liquid layer. This circumstance makes it possible, on the basis of physical models of the liquids boiling and taking into account the parameters of the surface state (temperature, pressure) and properties of the coolant (the density and heat capacity of the liquid, the specific heat of vaporization and the heat capacity of the vapor), and also the internal characteristics of the boiling of liquids, to calculate the value of specific heat flux q. In this paper, the difference in the mechanisms of heat transfer during the boiling of single-phase (water) and two-phase nanofluids has been studied and a quantitative estimate of the q values for the boiling of the nanofluid is carried out based on the internal characteristics of the boiling process. The satisfactory agreement of the calculated values with the experimental data is a confirmation that the key factor in the growth of the heat transfer intensity at the boiling of nanofluids is indeed a change in the nature and microrelief of the heating surface. Bibl. 20, Fig. 9, Tab. 2.

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THE SOIL PATTERN AND TRENDS IN WEST COAST AGRICULTURE SINCE 1964

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1981.42.1577 ◽

1981 ◽

pp. 19-28 ◽

Cited By ~ 1

Author(s):

D.B. Wright

Keyword(s):

West Coast ◽

Land Development ◽

Dairy Production ◽

Waste Land ◽

Development Costs ◽

Coastal Soils ◽

Physical Features ◽

Soil Pattern ◽

Great Scope

The physical features, climate and soils of the West Coast are described. Expansion since 1964 of dairy production, sheep and beef cattle numbers, and areas of improved grassland are highlighted, as is the role of the Crown in land development and settlement. While isolation and distance, development costs, river problems, and farmer attitude and knowledge are considered limitations, great scope exists for increased production by the adoption, of more intensive techniques, including horticulture on the best coastal soils, and by development of waste land.

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ABOUT HEAT CAPACITY OF TITANIUM CARBIDE TiCx

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2019.01-03.056-066 ◽

2019 ◽

pp. 56-66

Author(s):

I. Khidirov ◽

V. V. Getmanskiy ◽

A. S. Parpiev ◽

Sh. A. Makhmudov

Keyword(s):

Heat Capacity ◽

High Temperature ◽

Titanium Carbide ◽

Temperature Dependence ◽

Carbon Concentration ◽

Room Temperature ◽

Thermodynamic Characteristics ◽

Liquid Nitrogen Temperature ◽

Analysis Data ◽

Thermal Excitation

This work relates to the field of thermophysical parameters of refractory interstitial alloys. The isochoric heat capacity of cubic titanium carbide TiCx has been calculated within the Debye approximation in the carbon concentration range x = 0.70–0.97 at room temperature (300 K) and at liquid nitrogen temperature (80 K) through the Debye temperature established on the basis of neutron diffraction analysis data. It has been found out that at room temperature with decrease of carbon concentration the heat capacity significantly increases from 29.40 J/mol·K to 34.20 J/mol·K, and at T = 80 K – from 3.08 J/mol·K to 8.20 J/mol·K. The work analyzes the literature data and gives the results of the evaluation of the high-temperature dependence of the heat capacity СV of the cubic titanium carbide TiC0.97 based on the data of neutron structural analysis. It has been proposed to amend in the Neumann–Kopp formula to describe the high-temperature dependence of the titanium carbide heat capacity. After the amendment, the Neumann–Kopp formula describes the results of well-known experiments on the high-temperature dependence of the heat capacity of the titanium carbide TiCx. The proposed formula takes into account the degree of thermal excitation (a quantized number) that increases in steps with increasing temperature.The results allow us to predict the thermodynamic characteristics of titanium carbide in the temperature range of 300–3000 K and can be useful for materials scientists.

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