TUNNELLING MEASUREMENTS IN THE Bi SUPERCONDUCTORS

1989 ◽  
Vol 03 (01) ◽  
pp. 73-78 ◽  
Author(s):  
R. ESCUDERO ◽  
F. MORALES ◽  
F. ESTRADA ◽  
R. BARRIO
Keyword(s):  
Experimental Data ◽  
Temperature Dependence ◽  
Close Agreement

Tunnelling experiments made on a crack junction of Bi 2( Sr 0.56 Ca 0.39 Bi 0.05)3 Cu 2 O y show reproducible features in the I-V characteristic. Accurate measurements of the temperature dependence of these features show close agreement with the BCS behavior of the gap. Possible tunnelling processes in this material are discussed in connection with the experimental data.

TEMPERATURE DEPENDENCE OF THERMODYNAMIC PROPERTIES OF IONIC SOLIDS

2009 ◽  
Vol 23 (11) ◽  
pp. 2503-2509 ◽  
Author(s):  
S. K. SHARMA
Keyword(s):  
Experimental Data ◽  
Temperature Dependence ◽  
Volume Expansion ◽  
Close Agreement ◽  
Present Model ◽  
Expansion Ratio ◽  
Thermal Expansivity ◽  
Temperature Derivative ◽  
Computing Model ◽  
Ionic Solids

The present paper proposes a computing model for temperature dependence of volume thermal expansivity, volume expansion ratio and second order temperature derivative of volume based on the assumption that the product αKT remains constant at high temperatures and zero pressure. We have taken NaCl and KCl to testify the validity of the present model. A fairly close agreement between the calculated results and experimental data strongly supports the present model.

TEMPERATURE DEPENDENCE BEHAVIOR OF ELECTRICAL RESISTIVITY IN NOBLE METALS AT LOW TEMPERATURES

2014 ◽  
Vol 5 (3) ◽  
pp. 982-992 ◽  
Author(s):  
M AL-Jalali
Keyword(s):  
Experimental Data ◽  
Electrical Resistivity ◽  
Temperature Dependence ◽  
Concentration Dependence ◽  
Low Temperatures ◽  
Noble Metals ◽  
Phonon Scattering ◽  
Theoretical Models ◽  
Residual Resistivity ◽  
Electron Phonon Scattering

Resistivity temperature – dependence and residual resistivity concentration-dependence in pure noble metals(Cu, Ag, Au) have been studied at low temperatures. Dominations of electron – dislocation and impurity, electron-electron, and electron-phonon scattering were analyzed, contribution of these mechanisms to resistivity were discussed, taking into consideration existing theoretical models and available experimental data, where some new results and ideas were investigated.

scholarly journals Ability of Constitutive Models to Characterize the Temperature Dependence of Rubber Hyperelasticity and to Predict the Stress-Strain Behavior of Filled Rubber under Different Defor Mation States

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 369
Author(s):  
Xintao Fu ◽  
Zepeng Wang ◽  
Lianxiang Ma
Keyword(s):  
Experimental Data ◽  
Temperature Dependence ◽  
Mechanical Response ◽  
Constitutive Models ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Chain Model ◽  
Stress Strain ◽  
Filled Rubber ◽  
Yeoh Model

In this paper, some representative hyperelastic constitutive models of rubber materials were reviewed from the perspectives of molecular chain network statistical mechanics and continuum mechanics. Based on the advantages of existing models, an improved constitutive model was developed, and the stress–strain relationship was derived. Uniaxial tensile tests were performed on two types of filled tire compounds at different temperatures. The physical phenomena related to rubber deformation were analyzed, and the temperature dependence of the mechanical behavior of filled rubber in a larger deformation range (150% strain) was revealed from multiple angles. Based on the experimental data, the ability of several models to describe the stress–strain mechanical response of carbon black filled compound was studied, and the application limitations of some constitutive models were revealed. Combined with the experimental data, the ability of Yeoh model, Ogden model (n = 3), and improved eight-chain model to characterize the temperature dependence was studied, and the laws of temperature dependence of their parameters were revealed. By fitting the uniaxial tensile test data and comparing it with the Yeoh model, the improved eight-chain model was proved to have a better ability to predict the hyperelastic behavior of rubber materials under different deformation states. Finally, the improved eight-chain model was successfully applied to finite element analysis (FEA) and compared with the experimental data. It was found that the improved eight-chain model can accurately describe the stress–strain characteristics of filled rubber.

Interaction of Point Defects in Ice

1978 ◽  
Vol 21 (85) ◽  
pp. 115-122
Author(s):  
J. H. Bilgram ◽  
H. Gränicher
Keyword(s):  
Experimental Data ◽  
Dielectric Properties ◽  
Temperature Dependence ◽  
Point Defects ◽  
Low Frequency ◽  
Defect Concentration ◽  
Dielectric Measurements ◽  
Long Time ◽  
Nmr Techniques ◽  
Bjerrum Defect

AbstractThe interaction of point detects in ice has been neglected for a long time. Experimental data obtained from dielectric measurements on HF-doped crystals stimulated a new evaluation of the possibility of an interaction between Bjerrum defects and ions. In a previous paper it has been shown that this leads us to assume the existence of aggregates of Bjerrum defects and ions. In this paper these aggregates and Bjerrum defects are used to explain the dielectric properties of ice, especially the temperature dependence of the product of the high and low frequency conductivity σ0σ∞.The interaction of Bjerrum defects and impurity molecules leads to a dependence of the concentration of frenkel pairs on Bjerrum-defect concentration. At HF concentrations above the native Bjerrum-defect concentration the formation of a Frenkel pair is enhanced. This leads to the fast out-diffusion which has been studied in highly doped crystals by means of NMR techniques.

TEMPERATURE-DEPENDENCE OF PROTON CONDUCTIVITY IN HYDROGEN-BONDED MOLECULAR SYSTEMS

2007 ◽  
Vol 21 (19) ◽  
pp. 1239-1252 ◽  
Author(s):  
XIAO-FENG PANG ◽  
BO DENG ◽  
HUAI-WU ZHANG ◽  
YUAN-PING FENG
Keyword(s):  
Experimental Data ◽  
Electric Field ◽  
Temperature Dependence ◽  
Electric Conductivity ◽  
Proton Conductivity ◽  
Model System ◽  
Time Dependent ◽  
Molecular Systems ◽  
Damping Effect ◽  
Hydrogen Bonded

The temperature-dependence of proton electric conductivity in hydrogen-bonded molecular systems with damping effect was studied. The time-dependent velocity of proton and its mobility are determined from the Hamiltonian of a model system. The calculated mobility of (3.57–3.76) × 10-6 m 2/ Vs for uniform ice is in agreement with the experimental value of (1 - 10) × 10-2 m 2/ Vs . When the temperature and damping effects of the medium are considered, the mobility is found to depend on the temperature for various electric field values in the system, i.e. the mobility increases initially and reaches a maximum at about 191 K, but decreases subsequently to a minimum at approximately 241 K, and increases again in the range of 150–270 K. This behavior agrees with experimental data of ice.

scholarly journals Температурная зависимость ширины запрещенной зоны монокристаллов MnAgIn-=SUB=-7-=/SUB=-S-=SUB=-12-=/SUB=-

2019 ◽  
Vol 53 (12) ◽  
pp. 1621
Author(s):  
И.В. Боднарь ◽  
Б.Т. Чан ◽  
В.Н. Павловский ◽  
И.Е. Свитенков ◽  
Г.П. Яблонский
Keyword(s):  
Experimental Data ◽  
Temperature Dependence ◽  
Band Gap ◽  
Single Crystals ◽  
Spinel Structure ◽  
Semiconductor Materials ◽  
Transmittance Spectra ◽  
Temperature Range

AbstractMnAgIn_7S_12 single crystals 16 mm in diameter and ~40 mm in length are grown by planar crystallization of the melt. It is shown that the material grown crystallizes with the formation of the cubic spinel structure. From the transmittance spectra recorded in the region of fundamental absorption in the temperature range 10–320 K, the band gap E _ g of the single crystals and its temperature dependence are determined. The dependence has a shape typical of most semiconductor materials: as the temperature is lowered, the band gap E _ g increases. A calculation is carried out, and it is shown that the calculated values are in agreement with the experimental data.

Volumetric Changes in Cells During Freezing and Thawing

1980 ◽  
Vol 102 (2) ◽  
pp. 91-97 ◽  
Author(s):  
J. M. Knox ◽  
G. S. Schwartz ◽  
K. R. Diller
Keyword(s):  
Experimental Data ◽  
Image Analysis ◽  
Close Agreement ◽  
Living Cells ◽  
Freezing Process ◽  
Freezing And Thawing ◽  
Image Analysis Technique ◽  
Computerized Image Analysis ◽  
Analysis Technique ◽  
Thawing Process

A thermodynamic model is presented to describe the combined freezing and thawing process for living cells. Continuous changes in the cell volume are predicted according to the thermal protocol imposed on the system. Experimental verification of the model is sought by monitoring continuously the volume of cells as frozen on a cryomicroscope. The volumes of individual cells are measured from sequential photomicrographs by a computerized image analysis technique. The model and experimental data are in quite close agreement for the freezing process, but upon thawing the experimentally measured volumes consistently increased much more rapidly than predicted by the model. The model can be made to conform to the data by accounting for a substantial influx of electrolyte to the cell at subfreezing temperatures.

Energy Loss for Swift Heavy Ions in Different Elemental Absorbers: A Different Approach for Effective Charge Parameterization

2015 ◽  
Vol 238 ◽  
pp. 196-205
Author(s):  
B. Rani ◽  
Kalpana Sharma ◽  
Neetu ◽  
Anupam ◽  
Shyam Kumar ◽  
...  
Keyword(s):  
Experimental Data ◽  
Energy Loss ◽  
Effective Charge ◽  
Heavy Ions ◽  
Close Agreement ◽  
Input Parameter ◽  
Quantum Mechanical ◽  
Swift Heavy Ions ◽  
Calculated Energy ◽  
Semi Empirical

The energy loss for swift heavy ions, covering Z=3-29(~0.2 - 5.0MeV/n), has been calculated in the elemental absorbers like C, Al and Ti. The present calculations are based on Bohr’s approach applicable in both classical and quantum mechanical regimes. The major input parameter, the effective charge, has been calculated in a different way without any empirical/semi-empirical parameterization. The calculated energy loss values have been compared with the available experimental data which results in a close agreement.

Many Band Effects in Cuprate Superconductors

1997 ◽  
Vol 11 (13) ◽  
pp. 585-592
Author(s):  
S. P. Kruchinin ◽  
A. M. Yaremko ◽  
E. V. Mozdor
Keyword(s):  
Experimental Data ◽  
Fermi Level ◽  
Temperature Dependence ◽  
Theoretical Approach ◽  
Cuprate Superconductors ◽  
Electron Pair ◽  
Recent Experimental Data ◽  
Natural Manner ◽  
System A ◽  
Interacting Electrons

The new theoretical approach is proposed for study the states responsible for superconductivity of crystals. Within the frameworks of worked out approach it is shown that in electron–phonon system a class of new so-called coupled states arises. Postulated in BCS method electron-pair states k1 + k2 = 0, s + s′ = 0 are in natural manner included in this class. The model numerical calculations have shown that SC gap depends on number of bands crossing the Fermi level on the momenta k1+k2 = K≠ 0 of interacting electrons and that the temperature dependence of SC gap for HTSC is more complicated (in agreement with the recent experimental data) then predicted in BCS approach.

Temperature Dependence and Selective Excitation of the Phosphorus Related Photoluminescence in 4H-SiC

2009 ◽  
Vol 615-617 ◽  
pp. 263-266
Author(s):  
Ivan G. Ivanov ◽  
Jawad ul Hassan ◽  
Anne Henry ◽  
Erik Janzén
Keyword(s):  
Experimental Data ◽  
Temperature Dependence ◽  
Excited States ◽  
Selective Excitation ◽  
Tentative Explanation

The paper presents experimental data on the temperature dependence and the excitation properties of the phosphorus-related photoluminescence in 4H SiC. Two main sets of phonon replicas can be observed with selective excitation, which are attributed to two of the no-phonon lines observed in the spectrum. Some of the excited states are also attributed to one of the no-phonon lines on the ground of the selectively excited spectra. A tentative explanation of the observed features in terms of multiple bound excitons is proposed.

Sign in / Sign up

Export Citation Format

Share Document