scholarly journals Microwave Drying of Textile Materials and Optimization of a Resonant Applicator

10.14311/866 ◽  
2006 ◽  
Vol 46 (5) ◽  
Author(s):  
M. Pourová ◽  
J. Vrba
Keyword(s):  
Electric Field ◽  
Loss Factor ◽  
Microwave Drying ◽  
Electrical Characteristics ◽  
Dielectric Parameters ◽  
Open Type ◽  
Textile Materials ◽  
Factory Production ◽  
Measurement Results ◽  
Drying System

The principal aim of this work was to design and optimize the applicator for microwave drying. Our applicator is derived from the Fabry-Perrot resonator, which is an open type resonator.The whole system works at frequency 2.45 GHz and the magnetron that we used delivers power 800 W. This machine is intended for use in drying in factory production of fabrics. After identifying of the basic arrangement of the microwave drying machine, the next step in the design was the use of the electromagnetic field simulator. We determined the position of the magnetron and found the distribution of the electric field strength in drying textiles in this way. In parallel, we analyzed the drying system with analytical calculations. We created a diagram of the EM waves inside this structure and reached the resulting expression for use in calculating the strenght of the electric field in the plane of the drying textile. This quantity depends on the electrical characteristics of wet textiles, e.g. the permittivity and the loss factor. Measurements of these dielectric properties for the coburg is complicated, and this method makes it possible to solve our problem with dielectric parameters. We have SAR distribution results (by simulation and also by measurement), results of measurements of the moisture content in the dried textile with respect to time. These results are important for subsequent optimization of the efficiency of the whole machine. 

Usefulness of Foundry Tooling Materials in Microwave Heating Process

2013 ◽  
Vol 58 (3) ◽  
pp. 919-922 ◽  
Author(s):  
K. Granat ◽  
B. Opyd ◽  
D. Nowak ◽  
M. Stachowicz ◽  
G. Jaworski
Keyword(s):  
Electromagnetic Field ◽  
Microwave Heating ◽  
Loss Factor ◽  
Perturbation Technique ◽  
Resonant Cavity ◽  
Precise Determination ◽  
Heating Process ◽  
Basic Criterion ◽  
Measurement Results ◽  
Heating Technology

Abstract The paper describes preliminary examinations on establishing usefulness criteria of foundry tooling materials in the microwave heating technology. Presented are measurement results of permittivity and loss tangent that determine behaviour of the materials in electromagnetic field. The measurements were carried-out in a waveguide resonant cavity that permits precise determination the above-mentioned parameters by perturbation technique. Examined were five different materials designed for use in foundry tooling. Determined was the loss factor that permits evaluating usefulness of materials in microwave heating technology. It was demonstrated that the selected plastics meet the basic criterion that is transparency for electromagnetic radiation.

scholarly journals The Impact of Elongation on Change in Electrical Resistance of Electrically Conductive Yarns Woven into Fabric

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3390
Author(s):  
Željko Knezić ◽  
Željko Penava ◽  
Diana Šimić Penava ◽  
Dubravko Rogale
Keyword(s):  
Mathematical Model ◽  
Electrical Resistance ◽  
Electrically Conductive ◽  
Textile Materials ◽  
Measurement Results ◽  
Conductive Yarns ◽  
Yarn Count ◽  
As Relationship ◽  
The Impact ◽  
The Mathematical Model

Electrically conductive yarns (ECYs) are gaining increasing applications in woven textile materials, especially in woven sensors suitable for incorporation into clothing. In this paper, the effect of the yarn count of ECYs woven into fabric on values of electrical resistance is analyzed. We also observe how the direction of action of elongation force, considering the position of the woven ECY, effects the change in the electrical resistance of the electrically conductive fabric. The measurements were performed on nine different samples of fabric in a plain weave, into which were woven ECYs with three different yarn counts and three different directions. Relationship curves between values of elongation forces and elongation to break, as well as relationship curves between values of electrical resistance of fabrics with ECYs and elongation, were experimentally obtained. An analytical mathematical model was also established, and analysis was conducted, which determined the models of function of connection between force and elongation, and between electrical resistance and elongation. The connection between the measurement results and the mathematical model was confirmed. The connection between the mathematical model and the experimental results enables the design of ECY properties in woven materials, especially textile force and elongation sensors.

Computer-Aided Analysis and Measurement of an Interconnection System

2011 ◽  
Vol 308-310 ◽  
pp. 2279-2285
Author(s):  
Wei Chen Lee ◽  
Hill Wu
Keyword(s):  
Simulation Model ◽  
Frequency Domain ◽  
Insertion Loss ◽  
Return Loss ◽  
Design Phase ◽  
Electrical Characteristics ◽  
Impedance Mismatch ◽  
Measurement Results ◽  
Computer Aided Analysis ◽  
Computer Aided

The electrical characteristics of an interconnection system, which include impedance, insertion loss, and return loss, can greatly affect its performance as the signal speed increases. The objective of this research was to understand the discrepancy between the computer-aided analysis and measurement results of an interconnection system, so that a more accurate prediction of the electrical characteristics of this system can be made during the design phase. It was discovered that in both the time and frequency domain the computer-aided analysis results were consistent with the measurement results. Given these conclusions the simulation model was modified to improve the impedance mismatch within the interconnection system. It was found that by properly designing the antipad, the impedance mismatch can be greatly reduced.

scholarly journals Поведение керамических твердых растворов 33PbYb-=SUB=-1/2-=/SUB=-Nb-=SUB=-1/2-=/SUB=-O-=SUB=-3-=/SUB=--22PbZrO-=SUB=-3-=/SUB=--45PbTiO-=SUB=-3-=/SUB=- в электрическом поле

2020 ◽  
Vol 46 (6) ◽  
pp. 31
Author(s):  
Л.С. Камзина ◽  
G. Li
Keyword(s):  
Phase Transition ◽  
Dielectric Constant ◽  
Electric Field ◽  
Electric Fields ◽  
Dielectric Parameters ◽  
Morphotropic Phase Transition ◽  
Temperature Dependences ◽  
Pseudocubic Phase

The temperature dependences of the dielectric parameters were studied, as well as the changes in the dielectric constant with time in ceramic 33PbYb1 / 2Nb1 / 2O3-22PbZrO3-45 PbTiO3 samples in electric fields (0 <E <8 kV / cm). It is shown that in the phase existing below the temperature of the morphotropic phase transition, in addition to the rhombohedral and tetragonal phases, a small fraction of the relaxor pseudocubic phase is present. It was found that, unlike other relaxors, the dielectric constant practically does not change with time when an electric field is applied in the phase below the temperature of the morphotropic phase transition. Possible reasons for this behavior are discussed.

Improving photoluminescence, optical and electrical characteristics of PMMA films with gamma irradiation

2021 ◽  
Author(s):  
M.F. Zaki ◽  
Nasser Shubayr ◽  
Reda M Radwan ◽  
Yazeed Alashban
Keyword(s):  
Gamma Irradiation ◽  
Polymeric Materials ◽  
Advanced Materials ◽  
Strong Impact ◽  
Electrical Characteristics ◽  
Electrical Measurements ◽  
Indirect Transition ◽  
Dielectric Parameters ◽  
Vis Spectroscopy ◽  
Gamma Irradiated

Abstract Polymeric materials are macromolecules, essentially a combination of numerous repeated subunits. Polymers are innovative and advanced materials that currently have a strong impact on our daily lives. In recent years, polymer use has been prominent due to the materials’ distinctive properties; thus, they entered different fields of science, technology and industrial-biomedical applications.The improvement of photoluminescence, optical and electrical characteristics of non-conducting Poly(methyl methacrylate) (PMMA) films was studied. Upon gamma irradiation of various doses, the photophysical and electrical properties of PMMA films were investigated using photoluminescence spectroscopy, ultraviolet–visible (UV-Vis) spectroscopy and the LCR Meter Bridge Circuit technique. The fluorescent response improved the photoluminescence (PL) spectral emission peaks according to gamma values. Strong fluorescence peaks appeared with the highest gamma dose. The UV–Vis results revealed a significant red-shift in the absorption edge as gamma doses increased. This shift exhibits a continuous decrease in the energy band gap values (from 3.50 to 2.60 eV for direct transition and from 3.05 to 1.55 eV for indirect transition). This was due to the formation of carbon clusters, which led to an increase in the electrical conductivity and improved the dielectric parameters of the irradiated PMMA films. Among a variety of measurements presented and discussed in the present study, the electrical measurements showed improved electrical characteristics of gamma-irradiated PMMA films.

scholarly journals Comparative Analysis of the Thermal Insulation of Multi-Layer Thermal Inserts in a Protective Jacket

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2672
Author(s):  
Dubravko Rogale ◽  
Goran Majstorović ◽  
Snježana Firšt Rogale
Keyword(s):  
Thermal Properties ◽  
Comparative Analysis ◽  
Thermal Insulation ◽  
Professional Services ◽  
Cold Weather ◽  
Complete Analysis ◽  
Thermal Manikin ◽  
Scientific Methods ◽  
Textile Materials ◽  
Measurement Results

This paper presents the measurement results of the thermal insulation of the outer shell, thermal inserts, and clothing systems, as well as a comparative analysis of the thermal insulation of multi-layer thermal inserts in a thermal jacket intended for professional services in cold weather. Detachable thermal inserts are made of double-faced, diamond-shaped quilted lining with different masses per unit area, and together with the jacket, they form clothing systems with different thermal properties. Tests of the thermal properties of clothing were performed on a thermal manikin. They showed that an increase in the mass of thermal insulation textile materials contributes to an increase in the thermal insulation properties of clothing and are insufficient for a complete analysis of the thermal properties of clothing. Therefore, for the first time, three new parameters of integration efficiency of the thermal insert, thermal insulation efficiency parameters, and efficiency parameters of the integration of the textile material integrated into the clothing system were introduced. Based on these parameters, it is possible to perform an effective and accurate comparative analysis of the thermal insulation of multi-layer thermal inserts in clothing. This makes it possible to apply exact scientific methods largely in the technical design of the thermal properties of integrated textile materials, instead of experience-based methods as in the past.

scholarly journals Characterization of a Micro-Opto-Mechanical Transducer for the Electric Field Strength

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 855
Author(s):  
Wilfried Hortschitz ◽  
Andreas Kainz ◽  
Harald Steiner ◽  
Gabor Kovacs ◽  
Michael Stifter ◽  
...  
Keyword(s):  
Field Strength ◽  
Electric Field ◽  
Electric Field Strength ◽  
Resolution Limit ◽  
Strength Based ◽  
Measurement Results ◽  
Mechanical Transducer ◽  
Mems Technology ◽  
Order Of Magnitude ◽  
Set Up

We report on a new optical sensing principle for measuring the electric field strength based on MEMS technology. This method allows for distortion-free and point-like measurements with high stability regarding temperature. The main focus of this paper rests on an enhanced measurement set-up and the thereby obtained measurement results. These results reveal an improved resolution limit and point to the limitations of the current characterization approach. A resolution limit of 222 V/m was achieved while a further improvement of roughly one order of magnitude is feasible.

Low On-Resistance in 4H-SiC RESURF JFETs Fabricated with Dry Process for Implantation Metal Mask

2006 ◽  
Vol 527-529 ◽  
pp. 1203-1206 ◽  
Author(s):  
Takeyoshi Masuda ◽  
Kazuhiro Fujikawa ◽  
Kaoru Shibata ◽  
Hideto Tamaso ◽  
Satoshi Hatsukawa ◽  
...  
Keyword(s):  
Electric Field ◽  
Ion Implantation ◽  
Fabrication Process ◽  
Gate Length ◽  
Electrical Characteristics ◽  
Dry Process ◽  
Metal Mask ◽  
Surface Field ◽  
Reduced Surface

We fabricated 4H-SiC lateral JFETs with a reduced surface field (RESURF) structure, which can prevent the concentration of electric field at the edge of the gate metal [1]. Previously, we reported on the 4H-SiC RESURF JFET with a gate length (LG) of 10 μm [2]. Its specific on-resistance was 50 mΩcm2, which was still high. Therefore, a Ti/W layer was used as an ion implantation mask so as to decrease the thickness of the mask and to improve an accuracy of the device process. A RESURF JFET with the gate length (LG) of 3.0 μm was fabricated, and the specific on-resistance of 6.3 mΩcm2 was obtained. In this paper, the fabrication process and the electrical characteristics of the device are described.

CHARACTERISATION OF THE COMPLEX SHEAR MODULUS PROPERTIES OF ELECTRO-RHEOLOGICAL FLUIDS BY THE DIRECT STIFFNESS AND MASTER CURVE TECHNIQUES

1996 ◽  
Vol 10 (23n24) ◽  
pp. 3227-3236 ◽  
Author(s):  
S O Oyadiji
Keyword(s):  
Field Strength ◽  
Shear Modulus ◽  
Electric Field ◽  
Electric Field Strength ◽  
Loss Factor ◽  
Master Curve ◽  
Measured Temperature ◽  
Direct Stiffness ◽  
Er Fluid ◽  
Field Strengths

The direct stiffness technique was employed to characterise the complex modulus properties of a silicone oil-based electrorheological fluid over a frequency range from 30Hz to 300Hz and a temperature range from 0°C to 60ºC. The ER fluid device utilised was a set of concentric cylinders possessing a radial gap of 3mm between adjacent cylinders. Electric field strengths of between 0kV/mm and 2kV/mm were applied across the ER fluid. The results show that the shear modulus of the ER fluid decreased monotonically as the temperature was increased from 0ºC to 60ºC. Overall, the shear modulus decreased by a factor of up to 20. On the other hand, the shear loss factor increased from a low value of about 0.05 at 0ºC to a high value of about 1.0 at 60ºC. Conversely, as the electric field strength was increased from 0kV/mm to 2kV/mm, the shear modulus increased whereas the loss factor decreased. At all temperatures and electric field strengths of these investigations, both the shear modulus and loss factor increased in value as the excitation frequency was increased. The sets of measured temperature- and frequency-dependent data were converted, using the master curve technique, to master curves of shear modulus and loss factor which vary with frequency over several decades at a constant reference temperature and for varying levels of the electric field strength.

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