• Title/Summary/Keyword: far-infrared irradiation

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Effect of Far - Infrared Radiation on the Antioxidant Activity of Extracts from Citrus unshiu Peels (감귤 과피 추출물의 항산화능에 대한 원적외선 처리의 효과)

  • Jeong, Seok-Moon;Kim, So-Young;Park, Hae-Ryong;Lee, Seung-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.9
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    • pp.1580-1583
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    • 2004
  • The effect of far-infrared (FIR) radiation on the antioxidant activity of extracts from Citrus unshiu peels (CPs) was evaluated. CPs (5 g) were placed in Pyrex petri dishes (8.0 cm diameter) and irradiated at 150$^{\circ}C$ for 10, 20, 30, 40 or 50 min with a FIR heater. After FIR irradiation, 70% ethanol extract of CPs were prepared and total phenol contents (TPC), radical scavenging activity (RSA) and reducing power of the extracts were determined. FIR radiation of CPs at 150$^{\circ}C$ for 30 min increased the TPC and RSA of ethanol extract from 71.9${\mu}$M to 133.9 ${\mu}$M and from 29.64% to 51.27%, respectively, and reducing power was increased from 0.451 to 0.675, compared to those of non-irradiated control. These results indicated that FIR radiation onto CPs could liberate and activate covalently bound phenolic compounds that have antioxidant activities.

The Characteristics of Volume Resistivity for the Transformer Oil irradiated with the Electron Beam of Low Dose (저조사량 전자선에 대한 변압기유의 체적고유저항 특성)

  • 이용우;이우영;조돈찬;김왕곤;홍진웅
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.211-215
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    • 1996
  • In this paper, the volume resistivity of transformer oil is made researches so that the electrical properties for transformer oil is investigated. The specimen is produced by the irradiation of electron beam classified into the low dose, such as 0.5[Mrad], 1[Mrad], 2[Mrad]. The effect of electron team irradiation is studied by investigating the electrical properties of dielectric liquid due to the difference of electron beam dose. To measure the physical properties of transformer oil, courier Transform-Infrared Spectroscopy is investigated. And the study far the electrical properties is made by measuring the volume resistivity of each specimen. By means of the result from this experiments, it is introduced that the movement of carrier to contribute to the volume resistivity on the electrical properties.

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Effect of Far-Infrared Irradiation on the Antioxidant Activity of Extracts from Grape Seed (포도씨의 항산화능에 대한 원적외선 처리의 효과)

  • Jeong, Seok-Moon;Kim, So-Young;Ha, Jung-Uk;Lee, Seung-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.10
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    • pp.1619-1624
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    • 2005
  • The effect of far-infrared (FIR) irradiation on the antioxidant activity of extracts from grape seed (GS) was evaluated. GS (5 g) were placed in Pyrex petri dishes (8.0 cm diameter) md FIR irradiated at 150$^{\circ}C$ for 10, 20, 30, 40 or 60 min with a FIR heater. After FIR irradiation, water extract (WE) (1.0 g/10 mL), methanol extract (ME) (1.0 g/10 mL) and 70$\%$ ethanol extract (EE) (1.0 g/10 mL) of GS were prepared, and total phenol contents (TPC) and radical scavenging activity (RSA) of the extracts were determined. The antioxidant activities of GS extracts increased as FIR irradiation. For example, FIR irradiation of GS at 150$^{\circ}C$ for 10 min increased the TPC and RSA of WE from 0.95 mM to 1.84 mM and 33,87$\%$ to 58.55$\%$, respectively, compared to non-irradiated control. In the case of ME at the same conditions of FIR irradiation (150$^{\circ}C$ for 10 min), the TPC and RSA also increased from 3.4 mM to 4.52 mM and 76.55$\%$ to 89.41$\%$, respectively. The TPC and RSA of EE increased from 2.65 mM to 4.82 mM and 66.89$\%$ to 84.62$\%$, too. According to the GC/MS analysis, several low-molecular-weight phenolic compounds such as vanillic acid and 3,4-hydroxy benzoic acid were newly formed in the EE after FIR irradiated at 150$^{\circ}C$ for 10 min. There were slight differences in the kinds of phenolic compounds between EE of non irradiated control and FIR irradiated samples. These results indicated that FIR irradiation onto GS could enhance antioxidant activities of its extracts with increasing the amount of phenolic compounds.

Laser-induced Damage to Polysilicon Microbridge Component

  • Zhou, Bing;He, Xuan;Li, Bingxuan;Liu, Hexiong;Peng, Kaifei
    • Current Optics and Photonics
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    • v.3 no.6
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    • pp.502-509
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    • 2019
  • Based on the typical pixel structure and parameters of a polysilicon uncooled bolometer, the absorption rate of a polysilicon microbridge infrared detector for 10.6 ㎛ laser energy was calculated through the optical admittance method, and the thermal coupling model of a polysilicon microbridge component irradiated by far infrared laser was established based on theoretical formulas. Then a numerical simulation study was carried out by means of finite element analysis for the actual working environment. It was found that the maximum temperature and maximum stress of the microbridge component are approximately exponentially changing with the laser power of the irradiation respectively and that they increase monotonically. The highest temperature zone of the model is gradually spread by the two corners of the bridge surface that are not connected to the bridge legs, and the maximum stress acts on both sides of the junction of the microbridge legs and the substrate. The mechanism of laser-induced hard damage to polysilicon detectors is the melting damage caused by high temperature. This paper lays the foundation for the subsequent study of the interference mechanism of the laser on working state polysilicon detectors.