Complex Permeability Measurements of Microwave Ferrites1

1996 ◽  
Vol 430 ◽  
Author(s):  
Richard G. Geyer ◽  
Jerzy Krupka
Keyword(s):  
Saturation Magnetization ◽  
Measurement Data ◽  
Accurate Method ◽  
Ring Resonators ◽  
Complex Permeability ◽  
Microwave Frequencies ◽  
The Real ◽  
Theoretical Predictions

AbstractA rigorous and accurate method for the experimental determination of the complex permeability of demagnetized ferrites at microwave frequencies is presented. The measurement uses low- loss dielectric ring resonators, is nondestructive, and allows complex permeability characterization of a single ferrite sample to be performed at frequencies from 2 GHz to 25 GHz. A wide variety of ceramic microwave ferrites having various compositions and differing saturation magnetizations were measured in the demagnetized state. Generally, at any frequency greater than gyromagnetic resonance, the real part of the complex permeability increases as saturation magnetization increases.For the same frequency magnetic losses increases as saturation magnetization increases. The real permeability results are compared with magnetostatic theoretical predictions. Measurement data show excellent agreement with theoretical predictions, but only when 2πγMs/ω < 0.75, where γ is the gyromagnetic ratio, Ms is saturation magnetization, and ω is the radian rf frequency.

NOISE MEASUREMENTS FOR MATERIAL DIELECTRIC CHARACTERIZATION: APPLICATION TO A LIQUID CRYSTAL

2001 ◽  
Vol 01 (03) ◽  
pp. L125-L130 ◽  
Author(s):  
LEROY GÉRARD ◽  
GEST JOËL ◽  
TABOURIER PIERRE
Keyword(s):  
Liquid Crystal ◽  
Complex Permittivity ◽  
Dielectric Material ◽  
Voltage Noise ◽  
The Real ◽  
Dielectric Characterization ◽  
Noise Measurements

In this paper, we show how noise measurements can be used for the characterization of a dielectric material. This nonperturbative technique allows the determination of the real and imaginary parts of the complex permittivity from current and voltage noise measurements. This technique is illustrated hereafter for the case of an antiferroelectric liquid crystal.

Material Identification On Thin Shells Using the Virtual Fields Method, Demonstrated On the Human Eardrum

2021 ◽  
Author(s):  
Felipe Pires ◽  
Stephane Avril ◽  
Pieter Livens ◽  
Julio A. Cordioli ◽  
Joris Dirckx
Keyword(s):  
Experimental Data ◽  
Outer Surface ◽  
Plate Theory ◽  
Measurement Data ◽  
Total Strain ◽  
Virtual Fields Method ◽  
Material Parameters ◽  
Membrane Strain

Abstract Characterization of material parameters from experimental data remains challenging, especially on biological structures. One of such techniques allowing for the inverse determination of material parameters from measurement data is the Virtual Fields Method (VFM). However, application of the VFM on general structures of complicated shape has not yet been extensively investigated. In this paper, we extend the framework of the VFM method to thin curved solids in 3D, commonly denoted shells. Our method is then used to estimate theYoung's modulus and hysteretic damping of the human eardrum. By utilizing Kirchhoff plate theory, we assume that the behavior of the shell varies linearly through the thickness. The total strain of the shell can then be separated in a bending and membrane strain. This in turn allowed for an application of the VFM based only on data of the outer surface of the shell. We validated our method on simulated and experimental data of a human eardrum made to vibrate at certain frequencies. It was shown that the identified material properties were accurately determined based only on data from the outer surface and are in agreement with literature. Additionally, we observed that neither the bending nor the membrane strain in an human eardrum can be neglected and both contribute significantly to the total strain found experimentally.

Thermal-ionization isotope-dilution mass spectrometry as a definitive method for determination of potassium in serum.

1982 ◽  
Vol 28 (6) ◽  
pp. 1309-1313 ◽  
Author(s):  
J W Gramlich ◽  
L A Machlan ◽  
K A Brletic ◽  
W R Kelly
Keyword(s):  
Mass Spectrometry ◽  
Isotope Dilution ◽  
Isotope Dilution Mass Spectrometry ◽  
Accurate Method ◽  
Systematic Errors ◽  
Thermal Ionization ◽  
Mass Spectrometers ◽  
Definitive Method

Abstract Thermal-ionization isotope-dilution mass spectrometry is a highly precise and accurate method for the determination of potassium concentrations in serum. Although not suited for routine use because of the time and expense required, the technique provides an extremely valuable tool for the characterization of reference materials and for evaluating other analytical methods. The technique has recently been used to determine the concentration of potassium in a human serum standard, NBS Standard Reference Material 909. Seven vials of the serum were chemically processed and then analyzed by two spectroscopists independently, using different mass spectrometers. The results confirm previous work that indicates that a precision of 0.1% relative can be routinely achieved. The systematic errors in the method have been thoroughly evaluated. When the precise results are thus corrected, they are essentially bias free and hence definitive.

X-ray standing wave as a result of only the imaginary part of the atomic scattering factor

1999 ◽  
Vol 55 (2) ◽  
pp. 267-273 ◽  
Author(s):  
Riichirou Negishi ◽  
Tomoe Fukamachi ◽  
Takaaki Kawamura
Keyword(s):  
Standing Wave ◽  
Accurate Method ◽  
Anomalous Absorption ◽  
Acta Cryst ◽  
X Ray ◽  
The Real ◽  
Atomic Scattering Factor ◽  
Atomic Scattering ◽  
Scattering Factor

The X-ray standing wave has been studied when the real part of the scattering factor is zero. In the symmetric Laue case, the phase of the standing wave advances by π when the deviation parameter W changes from −1 to 1, which is the same variation as in the usual symmetric Bragg case when only the real part of the scattering factor exists. However, the phase in the former case is different from that in the latter by \pi/2. By using the standing waves, the origins of the anomalous transmission and anomalous absorption effects reported by Fukamachi & Kawamura [Acta Cryst. (1993), A49, 384–388] have been analysed. The standing wave in the Laue case can give rise to a more accurate method of site determination of a specified impurity atom as well as a wider range of applications than a conventional standing-wave approach.

scholarly journals REAL PART OF THE $\bar pp$ ELASTIC SCATTERING AMPLITUDE AT $\sqrt{s} = 546\, {\rm GeV}$

1991 ◽  
Vol 06 (32) ◽  
pp. 2973-2975 ◽  
Author(s):  
CLAUDE BOURRELY ◽  
JACQUES SOFFER ◽  
TAI TSUN WU
Keyword(s):  
Experimental Data ◽  
Elastic Scattering ◽  
Cross Section ◽  
Scattering Amplitude ◽  
Accurate Determination ◽  
The Real ◽  
Interference Region ◽  
Elastic Scattering Amplitude ◽  
Theoretical Predictions

In order to get an accurate determination of the real part of the [Formula: see text] elastic scattering amplitude at [Formula: see text], the Genoa–Palaiseau–Roma–Valencia collaboration plans to take experimental data on dσ/dt in the Coulomb interference region. We present detailed theoretical predictions for this cross-section. These predictions can be compared directly with the forthcoming data.

A method for the determination of the complex permittivity by detuned ring resonators for bulk materials up to 110 GHz

2015 ◽  
Vol 7 (3-4) ◽  
pp. 251-260 ◽  
Author(s):  
Armin Talai ◽  
Frank Steinhäußer ◽  
Achim Bittner ◽  
Ulrich Schmid ◽  
Robert Weigel ◽  
...  
Keyword(s):  
Effective Permittivity ◽  
Accurate Determination ◽  
Ring Resonators ◽  
Dielectric Losses ◽  
Bulk Materials ◽  
Resonance Frequencies ◽  
Measurement Results ◽  
Microwave Materials

An accurate characterization of microwave materials is essential for reliable high-frequency circuit design. This paper presents a measurement setup, which enables a quick and accurate determination of the relative permittivity of dielectric bulk materials up to 110 GHz. A ring-resonator is manufactured on a well-characterized substrate, serving as reference resonator. The material under test (MUT) is placed on top of the ring, which increases the effective permittivity and therefore introduces a shift of the resonance frequency of the resonator. In case of moderate to large dielectric losses of the MUTs, the quality factor of the resonator decreases perceptibly, which provides conclusions about the dielectric losses. Electromagnetic field simulations with different heights and relative permittivities of the MUTs provide a look-up table for the measured resonance frequencies. The functionality of the proposed measurement setup is validated by measurement results of different MUTs.

Dynamic Characterization of a Highly Flexible Reticular Structure

1996 ◽  
Vol 2 (4) ◽  
pp. 431-446
Author(s):  
Francesco Petrone ◽  
Rosario Sinatra ◽  
Giuseppe Tedoldi
Keyword(s):  
Dynamic Behavior ◽  
Real System ◽  
Experimental Methodology ◽  
Dynamic Characterization ◽  
Unusual Behavior ◽  
The Real ◽  
Acceptable Accuracy ◽  
Reticular Structure

Structural analysis in the dynamic field appears a particularly valid methodology in evaluating the behavior of the constructional solutions to particularly complex systems. The experimental determination of a structure's dynamic response can allow the development of a mathematical model that is able to simulate, with acceptable accuracy, the dynamic behavior of the real system. The model, which characterizes the structure, can then be used to interpret variations in the dynamic behavior subsequently detected in the real system, or to simulate unusual behavior when the corresponding input parameters can be defined. The present paper gives an example of this experimental methodology, analyzing the dynamic behavior of the cantilever roof of Favorita Stadium in Palermo.

Characterization of Impressed Current Technique to Model Corrosion of Reinforcement in Concrete

2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin
Keyword(s):  
Immersion Time ◽  
Chloride Content ◽  
Engineering Science ◽  
Coastal Regions ◽  
Faraday’S Law ◽  
Current Technique ◽  
Corrosion Cell ◽  
Impressed Current

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99

The Determination of Sense via Deleuze and Blanchot: Paradoxes of the Habitual, the Immemorial, and the Eternal Return

2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  
Eternal Return

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.

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