34 research outputs found
Electromagnetic Properties Of Metal Granular Composite Materials For EMC Applications
Electromagnetic properties of copper and Fe55Ni45alloy (Permalloy) composite materials have been studied by measuring the relative complex permeability (µr = µr’– jµr”), and permittivity (Σr = Σr’– jΣr”) spectra over the microwave range, as well as the a.c. electrical conductivity σac spectra. The variation of σac and Σr with particle content shows the insulator-metal transition due to the percolation effect. The effective cluster model can be applied to the percolation effect in permittivity. The permeability spectra in Permalloy composites, which contain the percolated particles, can be affected by the eddy current effect. The permeability relaxation frequency of Permalloy composites shifts to the higher frequencies by the oxidation of embedded particle surfaces. © 2012 IEEE
High Frequency Permeability Of Fe-Al-Si Granular Composite Materials
High-frequency electromagnetic properties of Fe-Al-Si alloy (Sendust) granular composite materials have been studied by measuring their relative complex permeability (μr = μr’ – jμr”) and permittivity (εr = εr’ – j εr”) spectra. The bulk Fe-Al-Si alloy shows metallic electrical conduction, and permeability decreases rapidly with frequency. On the other hand, Sendust powder shows relatively high electrical resistivity. Sendust composite material demonstrates insulating electrical properties up to at least 80 vol.% particle content. Thus the relatively high permeability in the microwave frequency range can be obtained. Frequency dispersion characteristics of permeability for the composite were analyzed by the superposition of domain wall and gyromagnetic spin resonance formula. The particle content variation of permeability can be qualitatively described by a coherent model mixing rule. © 2011 IEEE
Effect of Adding Chestnut Inner Skin on Allergenic Protein, Antioxidant Properties, and Quality of Bread
Wheat-dependent, exercise-induced anaphylaxis has no fundamental cure and requires patients to refrain from wheat consumption or to rest after eating. Although hypoallergenic wheat production by enzymatic degradation or thioredoxin treatment has been investigated, challenges still exist in terms of labor and efficacy. We investigated a hypoallergenic wheat product manufacturing technology that takes advantage of the property of tannins to bind tightly to proteins. Commercially available bread wheat (BW) and hypoallergenic wheat (1BS-18 “Minaminokaori”, 1BS-18M) were used. Chestnut inner skin (CIS) was selected as a tannin material based on the screening of breads with added unused parts of persimmon and chestnut. Hypoallergenicity was evaluated using Western blotting. The effect of CIS addition on the antioxidative properties of bread was also measured. For both BW and 1BS-18M, CIS addition reduced the immunoreactivity of wheat allergens. Antioxidant activities increased with increasing CIS substitution. However, 10% CIS-substituted breads were substantially less puffy. Five percent CIS substitution was optimal for achieving low allergenicity, while maintaining bread quality. The strategy investigated herein can reduce allergies related to wheat bread consumption. In this study, the evaluation of hypoallergenicity was limited to instrumental analysis. In the future, we will evaluate hypoallergenicity through clinical trials in humans