Impact of Impurity Phases and Superstoichiometric Iron on the Critical Temperature of Iron Chalcogenides

The aim of this research is to study the critical temperature depending on the pressure of one-band superconductor. We derive the exact equation of the critical temperature [Formula: see text] by using the BCS-like model. The effect of pressure and pseudogap on critical temperature has been investigated. The analytic form and the approximation of the critical temperature are shown. First, we consider the effect of pressure on the critical temperature and find that the critical temperature increased as pressure is increased which fits well with the experimental data of Tl-based and Bi-based superconductors. Second, the effect of the pseudogap on the critical temperature is considered. We found that the critical temperature is decreased as pressure increased which agrees to the data of [Formula: see text], the iron chalcogenides [Formula: see text], intermetallic compounds [Formula: see text] and [Formula: see text] superconductors.

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Meson masses and energies near the critical temperature with improved quenched Wilson quarks

Nuclear Physics B - Proceedings Supplements ◽

10.1016/s0920-5632(00)00338-8 ◽

2000 ◽

Vol 83-84 (1-3) ◽

pp. 402-404

Author(s):

P Schmidt

Keyword(s):

Critical Temperature

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Relationship between the Critical Temperature of Thermal Explosion and the Thickness of a Lead Azide Plane Crystal

Физика горения и взрыва ◽

10.15372/fgv20180112 ◽

2018 ◽

Keyword(s):

Critical Temperature ◽

Thermal Explosion ◽

Lead Azide

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Optical properties of the Vanadium dioxide

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v8i2.1520 ◽

2015 ◽

Vol 8 (2) ◽

pp. 2148-2155 ◽

Cited By ~ 1

Author(s):

Abderrahim Benchaib ◽

Abdesselam Mdaa ◽

Izeddine Zorkani ◽

Anouar Jorio

Keyword(s):

Energy Efficiency ◽

Optical Properties ◽

Critical Temperature ◽

Thin Layer ◽

Dielectric Function ◽

Vanadium Dioxide ◽

Ultra Violet ◽

Index Of Refraction ◽

Practical Utility ◽

Infra Red

The vanadium dioxide is a material thermo chromium which sees its optical properties changing at the time of theÂ transition from the phase of semiconductor state â†” metal, at a critical temperature of 68Â°C. The study of the opticalÂ properties of a thin layer of VOâ‚‚ thickness 82 nm, such as the dielectric function, the index of refraction, the coefficient ofextinction, the absorptionâ€™s coefficient, the reflectivity, the transmittivity, in the photonic spectrum of energy Ï‰ located inthe interval: 0.001242 â‰¤ Ï‰ (ev) â‰¤ 6, enables us to control well its practical utility in various applications, like the intelligentpanes, the photovoltaic, paintings for increasing energy efficiency in buildings, detectors of infra-red (I.R) or ultra-violet(U.V). We will make simulations with Maple and compare our results with those of the literature

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Control of the phase composition of advanced calcium phosphates using an x-ray diffractometer with a curved position-sensitive detector

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-6-29-35 ◽

2020 ◽

Vol 86 (6) ◽

pp. 29-35

Author(s):

V. P. Sirotinkin ◽

O. V. Baranov ◽

A. Yu. Fedotov ◽

S. M. Barinov

Keyword(s):

Phase Composition ◽

Calcium Phosphates ◽

Position Sensitive Detector ◽

Sensitive Detector ◽

X Ray Diffraction ◽

X Ray ◽

Impurity Phases ◽

Position Sensitive ◽

Diffraction Peaks ◽

Diffraction Patterns

The results of studying the phase composition of advanced calcium phosphates Ca10(PO4)6(OH)2, β-Ca3(PO4)2, α-Ca3(PO4)2, CaHPO4 · 2H2O, Ca8(HPO4)2(PO4)4 · 5H2O using an x-ray diffractometer with a curved position-sensitive detector are presented. Optimal experimental conditions (angular positions of the x-ray tube and detector, size of the slits, exposure time) were determined with allowance for possible formation of the impurity phases during synthesis. The construction features of diffractometers with a position-sensitive detector affecting the profile characteristics of x-ray diffraction peaks are considered. The composition for calibration of the diffractometer (a mixture of sodium acetate and yttrium oxide) was determined. Theoretical x-ray diffraction patterns for corresponding calcium phosphates are constructed on the basis of the literature data. These x-ray diffraction patterns were used to determine the phase composition of the advanced calcium phosphates. The features of advanced calcium phosphates, which should be taken into account during the phase analysis, are indicated. The powder of high-temperature form of tricalcium phosphate strongly adsorbs water from the environment. A strong texture is observed on the x-ray diffraction spectra of dicalcium phosphate dihydrate. A rather specific x-ray diffraction pattern of octacalcium phosphate pentahydrate revealed the only one strong peak at small angles. In all cases, significant deviations are observed for the recorded angular positions and relative intensity of the diffraction peaks. The results of the study of experimentally obtained mixtures of calcium phosphate are presented. It is shown that the graphic comparison of experimental x-ray diffraction spectra and pre-recorded spectra of the reference calcium phosphates and possible impurity phases is the most effective method. In this case, there is no need for calibration. When using this method, the total time for analysis of one sample is no more than 10 min.

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ALLEGHENY STAINLESS TYPE 405

Alloy Digest ◽

10.31399/asm.ad.ss0461 ◽

1985 ◽

Vol 34 (7) ◽

Keyword(s):

Fracture Toughness ◽

Corrosion Resistance ◽

High Temperature ◽

Critical Temperature ◽

Physical Properties ◽

Tensile Properties ◽

Heat Treating ◽

Ductile Material ◽

Air Cooling ◽

Temperature Performance

Abstract ALLEGHENY STAINLESS Type 405, unlike most other 12% chromium steels, is not subject to appreciable hardening through air cooling from high temperatures. This is an advantageous characteristic in those applications where a soft, ductile material is required after rapid cooling from above the critical temperature. The nonhardening tendency of Type 405 also retards the formation of hardening cracks where welding is employed. Its uses include annealing boxes and baffles where hardening during cooling would be undesirable. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as heat treating and machining. Filing Code: SS-461. Producer or source: Allegheny Ludlum Corporation.

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