• Title/Summary/Keyword: ESR

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The Detection of Irradiated Composite Seasoning Foods by Analyzing Photostimulated Luminescence (PSL), Electron Spin Resonance (ESR) and Thermoluminescence (TL) (PSL, ESR 및 TL 측정에 의한 복합조미식품의 방사선 조사여부 검지)

  • Kwon Joong-Ho;Kim Mi-Yeung;Kim Byeong-Keun;Chung Hyung-Wook;Kim Tae-Cheol;Kim Soo-Jin
    • Food Science and Preservation
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    • v.13 no.1
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    • pp.55-60
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    • 2006
  • Two kinds of composite seasoning products (beef broth powder, polk bone extract powder) were used for a detection trial of gamma irradiation treatment up to 10 kGy by analyzing photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence(TL). PSL results showed that the photon counts of non-irradiated samples were lower than 700, while those of irradiated samples were higher than 5000, which makes it possible to screen irradiated composite seasoning products at 1 kGy or over from the non-irradiated control. ESR signals measured for both irradiated samples were not irradiation-specific, even though they were dose dependent in the signal intensity. Radiation-induced TL glow curves were found in irradiated beef broth powder and furthernmore, TL ratio $(TL_4/TL_2)$ obtained by a re-irradiation step could verify the detection result of TL1 glow curves, showing ratios lower than 0.05 in the non-irradiated sample and higher than 1.00 in irradiated ones.

Physicochemical Quality and Detection Properties of Irradiated Powdered-Soups (감마선 조사된 분말수프의 이화학적 품질과 조사여부 판별특성)

  • Kwak, Ji-Young;An, Yeoung-Eun;Jung, Bo-Yun;Kwon, Joong-Ho
    • Current Research on Agriculture and Life Sciences
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    • v.30 no.2
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    • pp.82-89
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    • 2012
  • Commercial powdered soups, such as potato soup(PS), corn soup(CS), and chicken-herb soup(CHS), were gamma-irradiated at 0, 1, 5 and 10 kGy and subjected to physicochemical evaluation and identification trials by analyzing photostimulated luminescence(PSL), electron spin resonance(ESR), and thermoluminescence(TL). The changes in moisture content and pH of soup samples were negligible upon irradiation. The Hunter's color determinations showed that lightness (L value) decreased and yellowness (b value) increased as the irradiation dose increased in PS sample. The viscosity of irradiated samples was reduced in the order of PS, CS and CHS. The analyses of PSL, ESR and TL were applicable to the identification of irradiated powdered-soups at more than 1 kGy by detecting PSL photon counts/60 sec(over 5000), radiation-induced multicomponents-ESR signal, and typical TL glow curve at $150-250^{\circ}C$.

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Identification of Irradiated Food Additives by Photostimulated Luminescence (PSL) Method (Photostimulated Luminescence (PSL) 방법에 의한 국내 유통 분말형 식품가공원료의 방사선 조사 여부 모니터링)

  • Yun, Hyejeong;Hur, Jungmu;Yang, Suhyung;Lee, Byoung-Hun;Kwon, Joong-Ho;Kim, Dongho
    • Journal of Radiation Industry
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    • v.2 no.1
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    • pp.27-34
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    • 2008
  • Photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) analyses were conducted to detect whether 258 kinds of extracted and powdered forms food additives were irradiated or not. In a view of the PSL results, 9 kinds of the extracted and powdered samples (3.2%) showed over 5,000 photon counts $(60sec)^{-1}$ and these samples were judged to be irradiation-positive. Thirty nine kinds of the samples (15.6%) yielded 700~5,000 photon counts $(60sec)^{-1}$ and these samples were grouped into irradiation-potential, while the samples showed below 700 photon counts $(60sec)^{-1}$ sec were judged to be irradiation-negative. TL glow curves for minerals separated from 5 samples were detected at $150^{\circ}C$ with high intensity. However, TL analysis did not apply to other irradiation-positive and irradiation-potential samples because the minerals for TL detection were not separated from the samples. ESR measurements for irradiation-positive and irradiation-potential samples, judged by PSL detection, showed no specific signals to irradiation. The results indicated that PSL could be applied to identify irradiation treatment of extracted and powdered food additives, while TL was optional and ESR was not suitable for detection extracted and powdered food additives.

Effectiveness of Clinical Examination for Detection of Dermatophagoides farinae Allergen Asthma Disease (북아메리카 집먼지진드기에 의한 알레르기 천식 환자에서 임상검사의 유용성)

  • Choi, Woo-Soon;Kim, Sung-Chul;Choo, Sang-Kyu
    • Korean Journal of Clinical Laboratory Science
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    • v.37 no.1
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    • pp.16-21
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    • 2005
  • To find out the effectiveness of clinical examination for detection of dermatophagoides farinae allergen asthma disease, 50 patients (control group) and 50 healthy persons matched by sex and age to the control group, were tested for allergen asthma. The results of the study follow. The ESR there was significantly different from the comparisons of the patients' normal reference values, 95.3 % in ESR, patient groups allergen asthma and heamatology values with control group. The ESR level of allergen asthma patients, $62.23{\pm}35.09$ mm/hr, was higher than that of the controls, $9.47{\pm}5.36$ mm/hr (p<0.001). The eosinophil count level of the patients, $370.65{\pm}365.45mm^3$, was higher than that of the controls with $171.99{\pm}131.80mm^3$ (p<0.001). The IgE level of the patients, $1137.79{\pm}784.69IU/ml$, was higher than that of the controls with $71.29{\pm}14.28 IU/ml$ (p<0.001).

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Convenient Assay of O2- Generated on Potato Tuber Tissue Slices Treated with Fungal Elicitor by Electron Spin Resonance - No Secondary Oxidative Burst Induction by H2O2 Treatment

  • Park, Hae-Jun;Doke, Noriyuki
    • The Plant Pathology Journal
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    • v.21 no.3
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    • pp.283-287
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    • 2005
  • Since the discovery of generation of $O_2^-$ in plant, many evidence for the oxidative burst (OXB) has been accumulated in various combinations of plant and pathogen or elicitor systems. $O_2^-$ generating system responsible for the OXB was coupled with oxidation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) in microsomal fraction isolated from sliced aged potato tuber slices which were treated by hyphal wall components elicitor from Phytophthora infestans (HWC). We developed new assay method for quantitative measurement of oxygen radical $O_2^-$ by using electron spin resonance (ESR) analysis during elicitor­induced OXB on the surface of plant tissues. The ESR analysis using an $O_2^-$ trapper, Tiron (1,2-dihydroxy-3,5­benzenedisulfonic acid), provided a convenient assay for detecting only $O_2^-$ during elicitor-induced OXB producing various active oxygen species (AOS) on plant tissue surface. Tiron was oxidized to Tiron semiquinon radical by $O_2^-$. Quantity of the radical signal was measured by specific spectra on ESR spectroscopy. The level of $O_2^-$ was high in from surface of potato tuber tissue treated with hyphal cell wall elicitor (HWC) from Phytophthora infestans. There was no secondary OXB induction by $H_2O_2$ treatment in plant.

A study on the electromagnetic characteristics of the octadecylviologen-$(TCNQ^-)_2$ thin films with The Langmuir-Blodgett technique (LB법으로 제작된 octadecylviologen-$(TCNQ^-)_2$ 박막의 전자기적 특성 연구)

  • Shin, Dong-Myung;Park, Je-Sang;Lee, Chang-Keun;Kang, Dou-Yol
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.423-426
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    • 1995
  • Langmuir-Blodgett technique offers a convenient and elegant way to organic conducting systems for ultra thin films. In conducting systems based on LB films, TCNQ derivatives have been extensively studied as electron acceptor molecules in a large number of organic conducting systems.[1] A very interesting UV-visible spectra of octadecylviologen-$(TCNQ^-)_2$ was obtained from a methylenechloride and acetonitrile mixture, and from Langmuir-Blodgett films. The ESR characteristics of octadecylviologen-$(TCNQ^-)_2$ were studied to understand conducting mechanism and structure of LB films. The ESR spectra infer that the N-dococylquinolinium-TCNQ LB films has anisotropic property. But octadecylviologen-$(TCNQ^-)_2$ does not show angular dependence. As the temperature increases from 350K to 450K, the ESR signal of LB films becomes sharp. Scanning calorimetry(DSC) of octadecylviologen-$(TCNQ^-)_2$ provides the endothermic reaction temperature of the films, 340K, which corresponds to the temperature, 365K, of the new ESR signal.

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Determination of Free Radicals in Mainstream Cigarette Smoke by Electron Spin Resonance (전자스핀공명에 의한 담배연기 중 자유라디칼 측정)

  • Lee, Jeong-Min;Lee, John-Tae;Park, Jin-Won;Hwang, Keun-Joong
    • Journal of the Korean Society of Tobacco Science
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    • v.29 no.2
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    • pp.146-151
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    • 2007
  • Gas phase and particulate phase radicals in mainstream cigarette smoke were determined Electron Spin Resonance(ESR) spectroscopy. The free radicals in particulate phase have been investigated by benzene extract of Cambridge Filter Pad containing the smoke condensate. Spin trapping method in conjunction with ESR was used to investigate free radicals in the gas phase of cigarette smoke. Several analytical experiments were conducted in order to determine the optimal conditions for maximum signal intensities and reproducibility of results. All the tests were optimized and normalized using the University of Kentucky 2R4F reference cigarette. The optimal conditions were 0.6 mL for analysis volume of ESR, $4{\sim}5\;mL$ for collection volume of spin-adducts, and PBN for quantification of free radicals in gas phase. The radical levels of Kentucky 2R4F cigarettes were found $2.18{\times}10^{14}\;spins/cig.$ and $2.10{\times}10^{15}\;spins/cig.$ in gas phase.

Properties of PSL, TL, and ESR to Identify the Irradiated Sesame Seeds after Steaming

  • Lee, Jeon-Geun;Kausar, Tusneem;Chung, Hyung-Wook;Jeong, Il-Yun;Bhatti, Ijaz A.;Kwon, Joong-Ho
    • Food Science and Biotechnology
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    • v.18 no.2
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    • pp.374-378
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    • 2009
  • Three physical methods, photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR), have been applied to detect the irradiation treatment for the non- and steamed sesame seed samples. PSL successfully screened the irradiated samples from the non-irradiated control by comparing their photon counts (PCs) with the lower (less than 700 count/60 sec) and upper threshold values (higher than 5,000 count/60 sec). TL signals were still detected in all irradiated samples even after steaming, which was reconfirmed with TL ratios [integrated area of $TL_1$ (the first glow)/$TL_2$ (the second glow)] through re-irradiation step. ESR spectrometry showed that radiation-induced cellulose radicals were detected in all the irradiated samples irrespective of steaming treatment. Identification of the irradiated sesame seeds was possible even after steaming by analyzing PSL, TL, and ESR.

The Relationship Between Demographic Characteristics of Committee Members and Corporate Social Responsibility Commitment: Evidence from Thailand

  • JANGKRAJARNG, Varattaya;NUNTI, Chonrada;SANTIDHIRAKUL, Orapin
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.8
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    • pp.533-539
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    • 2021
  • This study aims to consider the role of women serving in the executive committee of the company and determine how it related to corporate social and environmental responsibilities (CSR and ESR). The data was collected from the 344 companies listed on the Stock Exchange of Thailand (SET) between 2013 and 2014. Especially, the CSR and ESR data was collected from the annual report and used to measure activities related to environmental and social responsibilities of companies listed on the SET. This study employed panel analysis regression to analyze the relationship between dependent and independent variables. The results indicated that the role of women who served in the executive committees of companies listed on SET had a positive impact on the social and environmental responsibilities of companies listed on the SET. The Granger causality test showed that the proportion of women holding positions on the board of directors had a statistically significant relationship with CSR and ESR, which is a unidirectional relationship. Moreover, the size of the company and the return to total assets also have a positive significant relationship with the CSR and ESR.

Adsorbate Interactions of Cu(II) Ion-Exchanged into Mesoporous Aluminosilicate MCM-41 Analyzed by Electron Spin Resonance and Electron Spin Echo Modulation

  • Kim, Jeong-Yeon;Yu, Jong-Sung
    • Journal of the Korean Magnetic Resonance Society
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    • v.3 no.2
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    • pp.109-126
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    • 1999
  • The location of Cu(II) exchanged into measoporous aluminosilicate MCM-41(AlMCM-41) material and its interaction with various adsorbate molecules were investigated by electron spin resonance and electron spin echo modulation spectroscopies. Cu(II) is fully coordinated to adsorbates in a wide open mesopore of AlMCM-41 for the formation of favorable complexes. It was found that in the fresh hydrated material, Cu(II) is octahedrally coordinated to six water molecules as evidenced by an isotropic room temperature ESR signal. This species is located in a cylindrical MCM-41 channel and rotates rapidly at room temperature. Evacuation at room temperature removes some of these water molecules, leaving the Cu(II) coordinated to less water molecules and anchored to oxygens in an MCM-41 channel wall. Dehydration at 450$^{\circ}C$ produces one Cu(II) species located on the internal wall of a channel, which is easily accessible to adsorbates. Adsorption of adsorbate molecules such as water, methanol, ammonia, pyridine, aniline, acetonitrile, benzene, and ethylene on a dehydrated Cu-AlMCM-41 material causes changes in the ESR spectrum of Cu(II), indicating the complex formation with these adsorbates. Cu(II) forms a complex with six molecules of methanol as evidenced by an isotropic room temperature ESR signal and ESEM analysis like upon water adsorption. Cu(II) also forms a square planar complex containing four molecules of N-containing adsorbates such as ammonia, pyridine and aniline based on resolved nitrogen superhyperfine interaction and their ESR parameters. However, Cu(II) forms a complex with six-molecules of acetonitrile based on ESR parameters. Only one molecule of benzene or ethylene is coordinated to Cu(II).

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