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A Survey on Foods of Principal Products in Jeollabukdo Area (전라북도 지역의 주요 특산물 중 식품에 대한 조사)

  • Kim Jeong-Ok;Choi Cha-Ran;Shin Mal-Shick
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.5
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    • pp.493-503
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    • 2005
  • This survey was performed to investigate the distribution of specialities which cultivated importantly in Jeollabukdo area in order to understand food culture of this area. Foods in speciality were divided into 4 groups, agricultural, aquatic, animal and the others products. Total number of 93 species of specialities, including 40 species of agricultural products, 29 species of aquatic products, 8 species of animal products and 16 species of the miscellaneous products, were identified from Jeollabukdo area. Especially, there were various fruits and vegetables among agricultural products and fishes among aquatic products in this region. Rice, pepper, pear, Mandarin fish, beef, pine mushroom, lentinus edodes and honey were determined as specialities in Jeollabukdo area. Various aquatic products were specialities in Gochang, Gunsan, Buan and Gimje region. Fruits, mushrooms, wild edible greens and animal products were specialities in Muju, Jangsu, Jeongeup and Jinan. Sweet fish, cat fish and freshwater crab were caught off in Sumjin river region only such as Namwon, Sunchang and Imsil, Recently, pumpkin(Cucurbita maxima) and paprika were determined as specialities in Jeollabukdo. In case of aquatic products, mushrooms and wild edible greens, their wild type products decreased, while cultivated type increased Commercialization by brand naming of agricultural and animal products were rapidly increasing. The kinds of specialities in Jeollabukdo area were changing by the influence of geographical, religious and social factors.

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Solution-Processable Field-Effect Transistors Fabricated Using Aryl Phenoxazine Based Polymers as the Active Layer

  • Yoon, Hye-Seon;Lee, Woo-Hyung;Lee, Ji-Hoon;Lim, Dong-Gun;Hwang, Do-Hoon;Kang, In-Nam
    • Bulletin of the Korean Chemical Society
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    • v.30 no.10
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    • pp.2371-2376
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    • 2009
  • Three phenoxazine-based conjugated polymers, namely, the aryl substituted phenoxazine homopolymer (P1) as well as the dimeric phenoxazine-fluorene (P2) and phenoxazine-bithiophene (P3) copolymers, were synthesized via the Ni(0) mediated Yamamoto reaction and the palladium-catalyzed Suzuki coupling reaction. The weight-averaged molecular weights ($M_w$) of P1, P2, and P3 were found to be 27,000, 22,000, and 15,000, respectively, and their polydispersity indices were 3.6, 1.8, and 2.1. All the polymers were soluble in common organic solvents such as chloroform, toluene, and so on. The UV-visible absorption maxima for P1, P2, and P3 in the film state were located at 421, 415 and 426 nm, respectively, and the ionization potentials of the polymers ranged between 4.90 and 5.12 eV. All the studied phenoxazine-based polymers exhibited amorphous behavior, as confirmed by X-ray diffraction (XRD) and atomic force microscopy (AFM) studies. Thin film transistors were fabricated using the top-contact geometry. P1 showed much better thin-film-transistor performance than P2 or P3: A thin film of P1 gave a saturation mobility of 0.81 ${\times}\;10^{-3}\;cm^2V^{-1}s^{-1}$ and an on/off ratio of about $10^2$.

Cobalt(III) Complex of Ethylenediamine-N,N'-di-${\alpha}$-Isobutyric Acid (Ethylenediamine-N,N'-di-${\alpha}$-Isobutyric Acid의 코발트(III) 착물)

  • Moo-Jin Jun;Chang-Yoon Han;Chang-Woo Park;Sung Rack Choi;Kwang-Ha Park
    • Journal of the Korean Chemical Society
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    • v.30 no.1
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    • pp.84-89
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    • 1986
  • A newflexible $N_2O_2$-type tetradentate ligand. Ethylenediamine-N,N'-di-${\alpha}$-isobutyric acid(eddib), has been synthesized, and dichloro cobalt(III) complex of eddib has been prepared via the air-oxidation technique. Only S-cis isomer has been yielded during the preparation of complex. Ring strain and steric hinderance are cited as the cause for the preference for the S-cis geometric configuration. On series of cobalt(III) complexes of eddib, $[Co(eddib)L]^{n+}$ $(L = Cl{\cdot}(H_2O),\;CO_3^{2-},\;(H_2O)_2)$have been prepared in situ. In their electronic absorption spectra, the absorption maxima and their intensities of the above series of complexes are on the ordinary line of the spectrochemical and hyperchromic series. Elemental analysis, IR, NMR and electronic absorption spectra have been used to characterize the complex and geometries of the complex.

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The Thermodynamics of the Formation of Polymethylbenzene-Halogens Charge Transfer Complexes (Ⅰ) (폴리메틸벤젠과 할로겐사이의 전하이동착물생성에 관한 열역학적 연구 (제1보))

  • Oh Cheun Kwun;Jin Burm Kyong
    • Journal of the Korean Chemical Society
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    • v.25 no.1
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    • pp.1-6
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    • 1981
  • Ultraviolet spectrophotometric investigations were carried out on the systems of o-, m-and p-xylene with iodine in carbon tetrachloride. The results reveal the formation of one to one molecular complexes of the type, $C_6H_4(CH_3)_2{\cdot}I_2. $The equilibrium constants of complexes were obtained in consideration of that absorption maxima has the blue shift with the increasing temperatures according to the formation of the charge transfer complexes. The thermodynamic parameters, $ {\Delta}$H, $ {\Delta}$G and $ {\Delta}$S for the formation of the charge transfer complexes were calculated from these values. These results combined with previous study of this series indicated that the relative stabilities of the polymethylbenzene complexes with iodine increase in the order, Benzene < Toluene < o-Xylene < p-Xylene These results are supposed to be the influence resulted from increase of electron density by the positive inductive effect and the steric hindrance effect.

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Spectrophotometric Determination of Some Fluoroquinolone Antibacterials through Charge-transfer and Ion-pair Complexation Reactions

  • El-Brashy, Amina Mohamed;Metwally, Mohamed El-Sayed;El-Sepai, Fawzi Abdallah
    • Bulletin of the Korean Chemical Society
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    • v.25 no.3
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    • pp.365-372
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    • 2004
  • Two simple, rapid and sensitive spectrophotometric methods for the determination of three fluoroquinolones, namely levofloxacin, norfloxacin and ciprofloxacin have been performed either in pure form or in their tablets. In the first method, levofloxacin and norfloxacin are directly treated with bromocresol green (BCG) in dichloromethane while ciprofloxacin is allowed to react with the same dye in aqueous acidic buffer. Highly yellow colored complex species were formed instantaneously in case of levofloxacin and norfloxacin or after extraction into dichloromethane for ciprofloxacin. The formed complexes are quantified spectrophotometrically at their absorption maxima at 411 nm for levofloxacin and 412 nm for norfloxacin and ciprofloxacin. The second method involves the reaction of levofloxacin with ${\rho}$-chloranilic acid ( ${\rho}$-CA) and norfloxacin with tetracyanoethylene (TCNE) in acetonitrile to give complexes with maximum absorbance at 521 and 333 nm for the two drugs, respectively. Adopting the first procedure, calibration graphs were linear over the range 1- 20 ${\mu}g\;mL^{-1}$ with mean percentage recoveries of 100.41 ${\pm}$ 0.72, 99.99 ${\pm}$ 0.54 and 100.23 ${\pm}$ 0.91 for the theree drugs, respectively. For the second procedure, the concentration ranges were 15-250 ${\mu}g\;mL^{-1}$ for levofloxacin using ${\rho}$-CA and 0.8-16 ${\mu}g\;mL^{-1}$ for norfloxacin using TCNE with mean percentage recoveries of 99.88 ${\pm}$ 0.45 and 100.26 ${\pm}$ 0.68 for the two drugs, respectively. The proposed methods were successfully applied to determine these drugs in their tablet formulations and the results compared favorably to that of reference methods. The proposed methods are recommended for quality control and routine analysis.

Comparison of log-logistic and generalized extreme value distributions for predicted return level of earthquake (지진 재현수준 예측에 대한 로그-로지스틱 분포와 일반화 극단값 분포의 비교)

  • Ko, Nak Gyeong;Ha, Il Do;Jang, Dae Heung
    • The Korean Journal of Applied Statistics
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    • v.33 no.1
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    • pp.107-114
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    • 2020
  • Extreme value distributions have often been used for the analysis (e.g., prediction of return level) of data which are observed from natural disaster. By the extreme value theory, the block maxima asymptotically follow the generalized extreme value distribution as sample size increases; however, this may not hold in a small sample case. For solving this problem, this paper proposes the use of a log-logistic (LLG) distribution whose validity is evaluated through goodness-of-fit test and model selection. The proposed method is illustrated with data from annual maximum earthquake magnitudes of China. Here, we present the predicted return level and confidence interval according to each return period using LLG distribution.

Process Characteristics for $YB_{2}Cu_{3}O_{7-d}$ Films Fabricated by Single Target Sputter and Surface Modification Technique

  • Lee, Eue-Jae
    • Korean Journal of Materials Research
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    • v.5 no.5
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    • pp.598-605
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    • 1995
  • Thin films of $YB_{2}Cu_{3}O_{7-d}$ were prepared on various substrated of MgO(100), $SrTiO_{3}$, and $LaAlO_{3}$ by using off-axis magentron sputtering methods and annealing in-situ. The prarameters of film fabrication processes had been optimized through a "follow the lcoal maxima" strategy to yield good quality films in therms of the critical temperature $T_{c}$ and the critical current density $J_{c}$. Optimizedproecsses employing a plane magndtron and an cylindrical magnetron yielded $T_{c}$>90K along with $J_{c}$$10^{6}$A/$\textrm{cm}^2$ at 77K and > 2${\times}$$10^{7}$A/$\textrm{cm}^2$ at 5K. The sampels, however, showed degradationinthe properties, after chemical etching for fabrication of microbridges with the line width of 2-10 mocrons. In particular, the value of $T_{c}$ for the microbridges of 2microns was as small as 80%. The degradation was strongly dependent on the line width through a formula : $T_{c}$(e)=$T_{c}$)b) [1-a exp(-1000 bL)} where $T_{c}$(e) and $T_{c}$ (b) are the values of $T_{c}$ in the absolute scale measured after and before chemical etching, respectively and L is the line width in mm. By utilizing a best fitting technique, the proper constant values of a and to b were found as exp(-1.2) and 0.22, respectively. This formula was very useful in estimatiing the upper limit of the device operationtemperature.

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Effects of Pumpkin (Cucurbita maxima Duch.) Fiber on Physicochemical Properties and Sensory Characteristics of Chicken Frankfurters

  • Choi, Yun-Sang;Kim, Hyun-Wook;Hwang, Ko-Eun;Song, Dong-Heon;Park, Jae-Hyun;Lee, Soo-Yeon;Choi, Min-Sung;Choi, Ji-Hun;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.32 no.2
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    • pp.174-183
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    • 2012
  • The effects of dietary fiber extracted from pumpkin (pumpkin fiber) on physicochemical properties, textural properties, and sensory characteristics of chicken frankfurters were investigated. Chicken frankfurter was supplemented with pumpkin fiber at levels of 0, 1, 2, 3, and 4%. Adding different levels of pumpkin fiber affected the proximate composition of the chicken frankfurters (p<0.05), except for protein content. In addition of different levels of pumpkin fiber influenced the physicochemical and textural properties of the chicken frankfurters (p<0.05). The yellowness, viscosity, and hardness were higher in chicken frankfurters samples containing pumpkin fiber than those in the control (p<0.05). The results showed that chicken frankfurter samples with higher pumpkin fiber levels had lower lightness values (p<0.05), as well as less cooking loss, emulsion stability, and lower color scores (p<0.05) compared to those control without pumpkin fiber treatment. The chicken frankfurters with 2% and 3% pumpkin fiber had higher overall acceptability than that of the control (p<0.05). The results show that adding pumpkin fiber produced acceptable chicken frankfurters and improved their quality characteristics.

Effects of Carnosine and Related Compounds on Monosaccharide Autoxidation and $H_2O_2$ Formation

  • Lee, Beom-Jun;Kang, Kyung-Sun;Nam, Sang-Yoon;Park, Jae-Hak;Lee, Yong-Soon;Yun, Young-Won;Cho, Myung-Haing
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.3
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    • pp.251-261
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    • 1999
  • The effects of carnosine and related compounds (CRCs) including anserine, homocarnosine, histidine, and ${\beta}-alanine$ on monosaccharide autoxidation and $H_2O_2$ formation were investigated. The incubation of CRCs with D-glucose, D-glucosamine, and D, L-glyceraldehyde at $37^{\circ}C$ increased the absorption maxima at 285 nm, 273 nm, and $290{\sim}330$ nm, respectively. D, L-glyceraldehyde was the most reactive sugar with CRCs. The presence of copper strongly stimulated the reaction of carnosine and anserine with D-glucose or D-glucosamine. Carnosine and anserine stimulated $H_2O_2$ formation from D-glucose autoxidation in a dose-dependent manner in the presence of 10 ${\mu}M$ Cu (II). The presence of human serum albumin (HSA) decreased their effect on $H_2O_2$ formation. Carnosine and anserine has a biphasic effect on ${\alpha}-ketoaldehyde$ formation from glucose autoxidation. CRCs inhibited glycation of HSA as determined by hydroxymethyl furfural, lysine residue with free ${\varepsilon}-amino$ group, and fructosamine assay. These results suggest that CRCs may be protective against diabetic complications by reacting with sugars and protecting glycation of protein.

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Relative Sunspot Number Observed from 2002 to 2011 at ButterStar Observatory

  • Oh, Sung-Jin;Chang, Heon-Young
    • Journal of Astronomy and Space Sciences
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    • v.29 no.2
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    • pp.103-113
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    • 2012
  • The ButterStar Observatory at the Dongducheon High School has been working for photographic observations of the Sun since October 16, 2002. In this study, we observed the Sun at the ButterStar observatory for 3,364 days from October 16, 2002 to December 31, 2011, and analyzed the photographic sunspot data obtained in 1,965 days. The correction factor $K_b$ for the entire observing period is 0.9519, which is calculated using the linear least square method to the relationship between the daily sunspot number, $R_B$, and the daily international relative sunspot number, $R_i$. The yearly correction factor calculated for each year varies slightly from year to year and shows a trend to change along the solar cycle. The correction factor is larger during the solar maxima and smaller during the solar minima in general. This implies that the discrepancy between a relative sunspot number, R, and the daily international relative sunspot number, $R_i$, can be reduced by using a yearly correction factor. From 2002 to 2008 in solar cycle 23, 35.4% and 64.6% of sunspot groups and 35.1% and 64.9% of isolated sunspots in average occurred in the northern hemisphere and in the southern hemisphere, respectively, and from 2008 to 2011 in solar cycle 24, 61.3% and 38.7% of sunspot groups and 65.0% and 35.0% of isolated sunspots were observed, respectively. This result shows that the occurrence frequency for each type of sunspot group changes along the solar cycle development, which can be interpreted as the emerging and decaying process of sunspot groups is different depending on the phase of solar cycle. Therefore, it is considered that a following study would contribute to the efforts to understand the dependence of the dynamo mechanism on the phase of solar cycle.