Some relations between elastic and physical parameters of pure metals

2006 ◽  
Vol 48 (6) ◽  
pp. 286-288 ◽  
Author(s):  
Alfred Buch
Keyword(s):  
Physical Parameters ◽  
Pure Metals

Model Prediction of Thermodynamics Activity in Multicomponent Liquid Alloy

2006 ◽  
Vol 313 ◽  
pp. 19-24 ◽  
Author(s):  
Tong Xiang Fan ◽  
Guang Jun Yang ◽  
Jian Qi Chen ◽  
Di Zhang
Keyword(s):  
Liquid Alloy ◽  
Model Prediction ◽  
Thermodynamic Model ◽  
Measured Data ◽  
Physical Parameters ◽  
Liquid Alloys ◽  
Miedema Model ◽  
Wilson Equation ◽  
Calculation Results ◽  
Pure Metals

This work presents a thermodynamic model to theoretically predict the component activity in multicomponent liquid alloy based on the Wilson equation and an extended Miedema model. Using only the physical parameters of pure metals, the component activities can be theoretically calculated and the calculation results agree well with the measured data. The model should enable very useful predictions to be made for activities in multi-component liquid alloys, especially for the trend of the activity changes with increasing alloy content.

scholarly journals Correlation of Physical Parameters with Steady-State Hardness of Pure Metals Processed by High-Pressure Torsion

2010 ◽  
Vol 667-669 ◽  
pp. 683-688 ◽  
Author(s):  
Kaveh Edalati ◽  
Z. Horita
Keyword(s):  
High Pressure ◽  
Steady State ◽  
High Pressure Torsion ◽  
Large Strains ◽  
Physical Parameters ◽  
Homologous Temperature ◽  
Pure Metals ◽  
Temperature Shear ◽  
And Diffusion ◽  
Hardness Values

Pure metals of 30 elements with various crystal structures (bcc, fcc, hcp, diamond cubic, complex cubic, primitive hexagonal and tetragonal) are processed by high-pressure torsion (HPT) and their mechanical properties are subsequently evaluated by Vickers microhardness measurements. For all metals, the hardness reaches steady states at large strains where the hardness remains unchanged with further straining. It is shown that the hardness values at the steady state are characteristics of each metal and are successfully expressed as a unique function of the homologous temperature, shear modulus and physical parameters of metals such as melting temperature, specific heat capacity and diffusion coefficient except for a few elements. The findings are well applicable to predict the ultimate steady-state hardness of metals attained by HPT processing through the correlation established in this study.

Some Results of the Spectroscopic Study of Four Close Binary Systems of Early Spectral Types

1965 ◽  
Vol 5 ◽  
pp. 120-130
Author(s):  
T. S. Galkina
Keyword(s):  
Spectroscopic Study ◽  
Spectral Type ◽  
Spectroscopic Investigation ◽  
Binary Systems ◽  
Quantitative Information ◽  
Close Binary ◽  
Physical Parameters ◽  
Absorption And Emission ◽  
Close Binary Systems ◽  
Quantitative Estimates

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.

A theory of contamination in electron microscopes by surface diffusion

1978 ◽  
Vol 36 (1) ◽  
pp. 116-117
Author(s):  
J.T. Fourie
Keyword(s):  
Electron Beam ◽  
Surface Diffusion ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Physical Parameters ◽  
Carbon Compounds ◽  
Hydrocarbon Molecules ◽  
Electron Microscopes ◽  
Primary Electrons ◽  
Long Chain

Contamination in electron microscopes can be a serious problem in STEM or in situations where a number of high resolution micrographs are required of the same area in TEM. In modern instruments the environment around the specimen can be made free of the hydrocarbon molecules, which are responsible for contamination, by means of either ultra-high vacuum or cryo-pumping techniques. However, these techniques are not effective against hydrocarbon molecules adsorbed on the specimen surface before or during its introduction into the microscope. The present paper is concerned with a theory of how certain physical parameters can influence the surface diffusion of these adsorbed molecules into the electron beam where they are deposited in the form of long chain carbon compounds by interaction with the primary electrons.

Electron Microscopy in the Study of Natural Phytoplankton Assemblages

1985 ◽  
Vol 43 ◽  
pp. 620-623
Author(s):  
Linda Sicko-Goad
Keyword(s):  
Electron Microscopy ◽  
Aquatic Environment ◽  
Size Range ◽  
Physical Parameters ◽  
Specific Information ◽  
Phytoplankton Assemblages ◽  
Phytoplankton Productivity ◽  
Ecosystem Effects ◽  
Time Of Year ◽  
Species Specific

Although the use of electron microscopy and its varied methodologies is not usually associated with ecological studies, the types of species specific information that can be generated by these techniques are often quite useful in predicting long-term ecosystem effects. The utility of these techniques is especially apparent when one considers both the size range of particles found in the aquatic environment and the complexity of the phytoplankton assemblages.The size range and character of organisms found in the aquatic environment are dependent upon a variety of physical parameters that include sampling depth, location, and time of year. In the winter months, all the Laurentian Great Lakes are uniformly mixed and homothermous in the range of 1.1 to 1.7°C. During this time phytoplankton productivity is quite low.

A New Numerical Model for Electron-Probe Analysis at High Depth Resolution

1996 ◽  
Vol 54 ◽  
pp. 490-491
Author(s):  
P.-F. Staub ◽  
C. Bonnelle ◽  
F. Vergand ◽  
P. Jonnard
Keyword(s):  
Electron Probe ◽  
Surface Segregation ◽  
Depth Distribution ◽  
Computing Time ◽  
Depth Resolution ◽  
Physical Parameters ◽  
Electron Probe Analysis ◽  
Interface Phases ◽  
Excitation Conditions ◽  
High Depth

Characterizing dimensionally and chemically nanometric structures such as surface segregation or interface phases can be performed efficiently using electron probe (EP) techniques at very low excitation conditions, i.e. using small incident energies (0.5<E0<5 keV) and low incident overvoltages (1<U0<1.7). In such extreme conditions, classical analytical EP models are generally pushed to their validity limits in terms of accuracy and physical consistency, and Monte-Carlo simulations are not convenient solutions as routine tools, because of their cost in computing time. In this context, we have developed an intermediate procedure, called IntriX, in which the ionization depth distributions Φ(ρz) are numerically reconstructed by integration of basic macroscopic physical parameters describing the electron beam/matter interaction, all of them being available under pre-established analytical forms. IntriX’s procedure consists in dividing the ionization depth distribution into three separate contributions:

Unifying Calibration Parameters for Dielectric Moisture Meter

2006 ◽  
Vol 2 (1) ◽  
pp. 73-94 ◽  
Author(s):  
Péter Mészáros ◽  
David B. Funk
Keyword(s):  
The United States ◽  
Temperature Correction ◽  
Physical Parameters ◽  
Correction Coefficient ◽  
Prototype System ◽  
United States Department ◽  
Very High Frequency ◽  
Grain Moisture ◽  
University Of Budapest ◽  
Improved Accuracy

The Unified Grain Moisture Algorithm is capable of improved accuracy and allows the combination of many grain types into a single “unified calibration”. The purposes of this research were to establish processes for determining unifying parameters from the chemical and physical properties of grains. The data used in this research were obtained as part of the United States Department of Agriculture-Grain Inspection, Packers and Stockyards Administration's Annual Moisture Calibration Study. More than 5,000 grain samples were tested with a Hewlett-Packard 4291A Material/Impedance Analyzer. Temperature tests were done with a Very High Frequency prototype system at Corvinus University of Budapest. Typical chemical and physical parameters for each of the major grain types were obtained from the literature. Data were analyzed by multivariate chemometric methods. One of the most important unifying parameters (Slope) and the temperature correction coefficient were successfully modeled. The Offset and Translation unifying parameters were not modeled successfully, but these parameters can be estimated relatively easily through limited grain tests.

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