scholarly journals Изменение температуры Кюри в пористом материале

2020 ◽  
Vol 46 (14) ◽  
pp. 6
Author(s):  
А.В. Шишулин ◽  
В.Б. Федосеев ◽  
А.В. Шишулина
Keyword(s):  
Curie Temperature ◽  
Cohesive Energy ◽  
Nanoporous Materials ◽  
Effective Diameter ◽  
Pore Shape ◽  
Magnetic Transitions ◽  
Shape Coefficient ◽  
Geometric Characteristics ◽  
Macroscopic Objects ◽  
Two Parameters

In this paper, the dependence of magnetic transitions temperatures of nanoporous materials on pore geometric characteristics (volume and shape) have been studied in the framework of the cohesive energy-based model in the case of pure nanoporous nickel and cobalt. Pore geometric characteristics have been taken into account using two parameters: its effective diameter and shape coefficient of a pore which characterizes the degree of deviation of its shape from the spherical one. The estimates allow expecting the possibility to obtain nanoporous macroscopic objects of ferromagnetic materials with a reduced Curie temperature which value also decreases with “complicating” the pore shape.

scholarly journals Analytical Design of the Human Bronchial Tree for Healthy Patients and Patients with Obstructive Pulmonary Diseases

2019 ◽  
Vol 14 (2) ◽  
pp. 635-648 ◽  
Author(s):  
A.E. Medvedev ◽  
P.S. Gafurova
Keyword(s):  
Airway Obstruction ◽  
Bronchial Tree ◽  
Pulmonary Diseases ◽  
Cylindrical Shape ◽  
Analytical Design ◽  
Geometric Characteristics ◽  
Analytical Formulas ◽  
Two Parameters ◽  
Pathological Case ◽  
Order Smoothness

The study is aimed at the analytical design of the full human bronchial tree for healthy patients and patients with obstructive pulmonary diseases. Analytical formulas for design of the full bronchial tree are derived. All surfaces of the bronchial tree are matched with the second-order smoothness (there are no acute angles or ribs). The geometric characteristics of the human bronchial tree in the pathological case are modeled by a “starry” shape of the inner structure of the bronchus; the pathology degree is defined by two parameters: bronchus constriction level and degree of distortion of the cylindrical shape of the bronchus. Closed analytical formulas allow the human bronchial tree of an arbitrary complexity (up to alveoli) to be designed; moreover, the parametric dependences make it possible to specify any desirable degree of airway obstruction.

Magnetic Transitions in the Double Perovskite Sr2FeRe1-xFexO6(0≤X≤0.5)

2008 ◽  
Vol 1119 ◽  
Author(s):  
Haitao Gao ◽  
Vadim Ksenofotov ◽  
Joachim Barth ◽  
Martin Panthöefer ◽  
Felser Claudia ◽  
...  
Keyword(s):  
Curie Temperature ◽  
Transport Properties ◽  
Solid Solutions ◽  
Magnetic Moment ◽  
Parent Compound ◽  
Structural Evolution ◽  
Double Perovskite ◽  
Magnetic Transitions ◽  
Mössbauer Data ◽  
Redox Buffer

AbstractThe synthesis, structure, and magnetic and transport properties of solid solutions Sr2FeRe1-xFexO6 (0≤x≤0.5) are reported. A structural evolution in the solid solutions from a double perovskite to perovskite is observed with increasing Fe/Re disorder. Except for the metallic parent compound all members of the series are semiconducting. For the Fe-doped samples a change from ferrimagnetic interactions in the parent compound to a complex superposition of ferrimagnetic and antiferromagnetic interactions was observed. The magnetic moment decreases with x, whereas the Curie temperature TC remains unaffected. The magnetic and Mössbauer data suggest Fe to act as a redox-buffer.

SPECIFIC HEAT ANOMALIES OF Mn3AlC AND Mn3ZnC

1962 ◽  
Vol 40 (6) ◽  
pp. 719-724 ◽  
Author(s):  
M. L. Swanson
Keyword(s):  
Curie Temperature ◽  
Specific Heat ◽  
Ferromagnetic State ◽  
Higher Order ◽  
Magnetic Transitions ◽  
Specific Heats ◽  
Ordered Alloys

The specific heats of the ordered alloys Mn3AlC and Mn3ZnC were measured from −150 to 100 °C. A single higher-order anomaly was observed at the Curie temperature (−9 °C) of Mn3AlC, indicating that a ferromagnetic state existed above −150 °C. The two specific heat anomalies observed for Mn3ZnC at −35 and 65 °C showed that two co-operative magnetic transitions occurred in this alloy.

Cation distribution dependent magnetic properties in CoCr2−xFexO4 (x = 0.1 to 0.5): EXAFS, Mössbauer and magnetic measurements

2017 ◽  
Vol 46 (31) ◽  
pp. 10300-10314 ◽  
Author(s):  
D. Kumar ◽  
A. Banerjee ◽  
A. Mahmoud ◽  
Chandana Rath
Keyword(s):  
Phase Transition ◽  
Magnetic Properties ◽  
Curie Temperature ◽  
Cation Distribution ◽  
Magnetic Measurements ◽  
Magnetic Transitions ◽  
Ferrimagnetic Phase ◽  
Evolution Of Structure ◽  
Lock In

Evolution of structure and rich magnetic transitions such as paramagnetic to ferrimagnetic phase transition at Curie temperature (TC), spiral ordering temperature (TS) and lock-in temperature (TL) have been discussed in CoCr2O4 spinel multiferroic after substituting Fe.

Two Universal Equations of State for Solids

2010 ◽  
Vol 65 (1-2) ◽  
pp. 34-44
Author(s):  
Jiu-Xun Sun ◽  
Qiang Wu ◽  
Yang Guo ◽  
Ling-Cang Cai
Keyword(s):  
Cohesive Energy ◽  
Equations Of State ◽  
Second Best ◽  
Practical Applications ◽  
The Third ◽  
Lennard Jones ◽  
Compression Data ◽  
Two Parameters

AbstractIn this paper, two equations of state (EOSs) (Sun Jiu-Xun-Morse with parameters n = 3 and 4, designated by SMS3 and SMS4) with two parameters are proposed to satisfy four merits proposed previously and give improved results for the cohesive energy. By applying ten typical EOSs to fit experimental compression data of 50 materials, it is shown that the SMS4 EOS gives the best results; the Baonza and Morse EOSs give the second best results; the SMS3 and modified generalized Lennard-Jones (mGLJ) EOSs give the third best results. However, the Baonza and mGLJ EOSs cannot give physically reasonable values of cohesive energy and P-V curves in the expansion region; the SMS3 and SMS4 EOS give fairly good results, and have some advantages over the Baonza and mGLJ EOSs in practical applications.

scholarly journals Method of Constructing an Asymmetric Human Bronchial Tree in Normal and Pathological Cases

2020 ◽  
Vol 15 (2) ◽  
pp. 148-157
Author(s):  
v. Medvedev
Keyword(s):  
Airway Obstruction ◽  
Bronchial Tree ◽  
Pulmonary Diseases ◽  
Cylindrical Shape ◽  
Analytical Design ◽  
Geometric Characteristics ◽  
Analytical Formulas ◽  
Two Parameters ◽  
Pathological Case ◽  
Order Smoothness

The goal of the study is the analytical design of the full asymmetric human bronchial tree (irregular dichotomy) for healthy patients and patients with obstructive pulmonary diseases. For this purpose, the author has derived the special analytical formulas. All surfaces of the bronchial tree are matched with the second-order smoothness (there are no acute angles or ribs). The geometric characteristics of the human bronchial tree in the pathological case are modeled by a “starry” shape of the inner structure of the bronchus; a level of the pathology is defined by two parameters: bronchus constriction level and level of distortion of the cylindrical shape of the bronchus. Closed analytical formulas allow a researcher to construct the human bronchial tree of an arbitrary complexity (up to alveoli); moreover, the parametric dependences make it possible to specify any desirable level of airway obstruction.

Photo-electric Hβ and uvby photometry

1966 ◽  
Vol 24 ◽  
pp. 170-180
Author(s):  
D. L. Crawford
Keyword(s):  
Narrow Band ◽  
Line Strength ◽  
Interference Filter ◽  
B Stars ◽  
Relative Line ◽  
The Mean ◽  
F Stars ◽  
Two Parameters ◽  
Filter Photometry ◽  
The Continuum

Early in the 1950's Strömgren (1, 2, 3, 4, 5) introduced medium to narrow-band interference filter photometry at the McDonald Observatory. He used six interference filters to obtain two parameters of astrophysical interest. These parameters he calledlandc, for line and continuum hydrogen absorption. The first measured empirically the absorption line strength of Hβby means of a filter of half width 35Å centered on Hβand compared to the mean of two filters situated in the continuum near Hβ. The second index measured empirically the Balmer discontinuity by means of a filter situated below the Balmer discontinuity and two above it. He showed that these two indices could accurately predict the spectral type and luminosity of both B stars and A and F stars. He later derived (6) an indexmfrom the same filters. This index was a measure of the relative line blanketing near 4100Å compared to two filters above 4500Å. These three indices confirmed earlier work by many people, including Lindblad and Becker. References to this earlier work and to the systems discussed today can be found in Strömgren's article inBasic Astronomical Data(7).

Radiation Damage of Support Films

1981 ◽  
Vol 39 ◽  
pp. 28-29
Author(s):  
H.A. Cohen ◽  
W. Chiu
Keyword(s):  
Transfer Function ◽  
Low Temperatures ◽  
Carbon Support ◽  
Contrast Transfer Function ◽  
Electron Dose ◽  
Imaging Parameters ◽  
Negative Stain ◽  
Phase Corrections ◽  
Two Parameters ◽  
Medium Dose

The goal of imaging the finest detail possible in biological specimens leads to contradictory requirements for the choice of an electron dose. The dose should be as low as possible to minimize object damage, yet as high as possible to optimize image statistics. For specimens that are protected by low temperatures or for which the low resolution associated with negative stain is acceptable, the first condition may be partially relaxed, allowing the use of (for example) 6 to 10 e/Å2. However, this medium dose is marginal for obtaining the contrast transfer function (CTF) of the microscope, which is necessary to allow phase corrections to the image. We have explored two parameters that affect the CTF under medium dose conditions.Figure 1 displays the CTF for carbon (C, row 1) and triafol plus carbon (T+C, row 2). For any column, the images to which the CTF correspond were from a carbon covered hole (C) and the adjacent triafol plus carbon support film (T+C), both recorded on the same micrograph; therefore the imaging parameters of defocus, illumination angle, and electron statistics were identical.

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