Sort by:
Publication Type:
Open access:
Publication Date:
Periodicals:
Search results
Online since: March 2015
Authors: Georgiy Firstov, Yuri Koval, Jan van Humbeeck, Andrey Timoshevskii, Tetiana Kosorukova, Pavlo Verhovlyuk
Introduction
Starting from the pioneering works of Georgiy Kurdyumov and coauthors [1,2], dedicated to the investigation of the mechanism, thermodynamics, kinetics and specifics of the martensitic transformations (MT), the number of structural studies of these transformations is constantly growing.
At the same time, during the last 20 years the number of publications dedicated to high temperature MT and SME is growing [18-20].
In B19` structure the number of the nearest Cu atoms equals to 2 and they are situated much nearer than Zr atoms.
Thus, precisely the interaction of atoms with a large number of valence d-electrons is the driving force behind the transformation of B2 structure.
Another important attractive feature of ZrCu-based alloys is the fact that they are so-called linear intermetallic compounds, just like the binary ZrCu and precipitation of intermetallic phases on grain boundaries (like in Ti-Ni-Zr and Ti-Ni-Hf) is less probable if one can maintain quasibinary stoichiometry.
At the same time, during the last 20 years the number of publications dedicated to high temperature MT and SME is growing [18-20].
In B19` structure the number of the nearest Cu atoms equals to 2 and they are situated much nearer than Zr atoms.
Thus, precisely the interaction of atoms with a large number of valence d-electrons is the driving force behind the transformation of B2 structure.
Another important attractive feature of ZrCu-based alloys is the fact that they are so-called linear intermetallic compounds, just like the binary ZrCu and precipitation of intermetallic phases on grain boundaries (like in Ti-Ni-Zr and Ti-Ni-Hf) is less probable if one can maintain quasibinary stoichiometry.
Online since: September 2013
Authors: Leonid Lobanov, Vyacheslav Pivtorak, Viktor Savitsky, Galina Tkachuk
Different numbers of fringes in the left and right sides relative to the hole indicates the presence of gradient of residual stresses over the surface (Fig.1.b).
Thus, the use of the proposed techniques for the stress gradient analyses enabled to clarify the data about distribution of residual stresses and to identify a number of the important features.
Thus, the use of the proposed techniques for the stress gradient analyses enabled to clarify the data about distribution of residual stresses and to identify a number of the important features.
Online since: March 2008
Authors: A.L. Udovsky
The theoretical basis for development of general calculated methods of PDs was analytical
thermodynamics as binary for as multi-component systems, which also permitted analysis of the
behavior of thermodynamic properties at grain boundaries and in multiphase fields of PDs.
development and applications of the thermodynamic theory of phase diagrams of multi-components systems progresses in four directions. 1) Construction of models for different phases (melts, disordered solutions, ordering solutions, multi-sub-lattice chemical compounds, stratifying melts and solid solutions and so on) and derivation of explicit and implicit relationships between thermodynamic properties as function of composition, temperature and pressure and kinds of phase diagrams on one hand and values of model parameters, on the other hand; 2) Development of general calculation methods for phase diagrams of multi-component systems, applicable a wide class of models, taking into account the Gibbs energies of the different phases, assigned explicitly and implicitly by their arguments; 3) After thermodynamically stable phase diagrams of multi-component systems were constructed, analysis of the behavior and calculation of the functions of thermodynamic properties at grain
The special interest presents creation it is enough general methods and computer programs, which enabled to conduct the calculation 1) in broad spectrum of the models, 2) for large number of the competitive phases, considered simultaneously, 3) mode, greatly drawn near to autonomous (without intermediate participation in calculation of the specialist).
We shall note that total number variables for Gibbs free energy of two-phase of the open binary system equals 6 (variables αα BA nn , , ββ BA nn , , as well as variables T and p).
In purposes of the reduction of the number independent variable we shall go from consideration open two-phase system to consideration to closed two-phase system.
development and applications of the thermodynamic theory of phase diagrams of multi-components systems progresses in four directions. 1) Construction of models for different phases (melts, disordered solutions, ordering solutions, multi-sub-lattice chemical compounds, stratifying melts and solid solutions and so on) and derivation of explicit and implicit relationships between thermodynamic properties as function of composition, temperature and pressure and kinds of phase diagrams on one hand and values of model parameters, on the other hand; 2) Development of general calculation methods for phase diagrams of multi-component systems, applicable a wide class of models, taking into account the Gibbs energies of the different phases, assigned explicitly and implicitly by their arguments; 3) After thermodynamically stable phase diagrams of multi-component systems were constructed, analysis of the behavior and calculation of the functions of thermodynamic properties at grain
The special interest presents creation it is enough general methods and computer programs, which enabled to conduct the calculation 1) in broad spectrum of the models, 2) for large number of the competitive phases, considered simultaneously, 3) mode, greatly drawn near to autonomous (without intermediate participation in calculation of the specialist).
We shall note that total number variables for Gibbs free energy of two-phase of the open binary system equals 6 (variables αα BA nn , , ββ BA nn , , as well as variables T and p).
In purposes of the reduction of the number independent variable we shall go from consideration open two-phase system to consideration to closed two-phase system.
Online since: January 1993
Authors: T. Watanabe
Online since: August 2015
Authors: Hardev Singh Virk
To understand the annealing mechanism a number of models were proposed [40, 64, 70 – 74].
In many experiments, a sample containing defects is gradually heated at a constant rate, and a physical property, P, related to the number of defects is observed during the annealing.
It is beyond the scope of this review to discuss all those attempts made by a number of geochronologists.
The time precision, however, may in fact be important in short-term experiments due to the time necessary for reaching the thermal equilibrium within the zircon grains.
In many experiments, a sample containing defects is gradually heated at a constant rate, and a physical property, P, related to the number of defects is observed during the annealing.
It is beyond the scope of this review to discuss all those attempts made by a number of geochronologists.
The time precision, however, may in fact be important in short-term experiments due to the time necessary for reaching the thermal equilibrium within the zircon grains.
Online since: September 2009
Authors: Philippe Colomban
A new generation of engineered nanomaterials (grain size <100 nm) has been in development - if
not already commercially available - for the last twenty years.
The huge number of mosaic tesserae is due to a quasi industrial production of glass ingots during Roman times.
This decreases the number of Si-O bridges and the connectivity of the network, i.e. modifies the glass nanostructure and associated properties such as the melting temperature, viscosity, thermal expansion….
The number of studied samples remains limited: for instance no real data are available by TEM for Cassius purple glaze and for red flambé potteries.
The huge number of mosaic tesserae is due to a quasi industrial production of glass ingots during Roman times.
This decreases the number of Si-O bridges and the connectivity of the network, i.e. modifies the glass nanostructure and associated properties such as the melting temperature, viscosity, thermal expansion….
The number of studied samples remains limited: for instance no real data are available by TEM for Cassius purple glaze and for red flambé potteries.
Online since: March 2015
Authors: Vasili Rubanik, Vladimir Klubovich, Vasili Rubanik
More effective thermal effects of ultrasound as compared with common heating methods is due to the fact that the ultrasonic vibration energy is absorbed mainly in the crystal structure irregularities (dislocations, grain boundaries and interphase, point defects, etc.), while the absorbed thermal energy is distributed evenly throughout the volume.
The system can be described by the following set of equations: ; , ; (1) , ; , , , where T1 and T2 – temperature of the rod and the concentrator, respectively; T0 – the initial temperature of the rod; – the temperature coefficients of conductivity; а1,2 – heat conductivity; с1,2 – specific heat; r1,2 – densities; – the deformation amplitude at the antinode; – the amplitude of displacement at the free end of the rod; – the oscillation frequency; – the modulus of elasticity; Q-1 – internal friction, – the sample length; – displacement relative to the beginning of the sample; t – time of ultrasonic influence, temperature conductivity; – wave number.
The system can be described by the following set of equations: ; , ; (1) , ; , , , where T1 and T2 – temperature of the rod and the concentrator, respectively; T0 – the initial temperature of the rod; – the temperature coefficients of conductivity; а1,2 – heat conductivity; с1,2 – specific heat; r1,2 – densities; – the deformation amplitude at the antinode; – the amplitude of displacement at the free end of the rod; – the oscillation frequency; – the modulus of elasticity; Q-1 – internal friction, – the sample length; – displacement relative to the beginning of the sample; t – time of ultrasonic influence, temperature conductivity; – wave number.
Online since: June 2010
Authors: Aldo Roberto Boccaccini, Lutz Christian Gerhardt
The
formation of crystalline HA was shown to reinforce the CPC inter-phases, suggesting that BSA acts
as a promoter of calcium phosphate crystal growth when bound to the surface of CPC grains [51].
Cell viability in all constructs was consistently above 85 %, and the cell number was statistically unchanged after 7 days.
Cell viability in all constructs was consistently above 85 %, and the cell number was statistically unchanged after 7 days.
Online since: December 2025
Authors: Dipankar Sarkar, Pritam Chakraborty, Somnath Paul
A novel geocell retaining wall having a variable cross-section was proposed by Song et al. (2016) [14], demonstrating a significant decrease in the number of reinforcement layers and an increase in structural effectiveness.
Experimental study on buffering system for concrete retaining walls using geocell filled with single-grain crushed stone.
Experimental study on buffering system for concrete retaining walls using geocell filled with single-grain crushed stone.