• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.662-667
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• 2009

In this study, four Korean black raspberry wines were developed using raspberries from different regions in Korea; Gochang (G), Hoengseong (H), Jeongeup (J), Sunchang (S). Sample wines were monitored for titratable acidity, ethanol, pH, reducing sugar content, color intensity, hue, total phenolic content, and organic acids during alcoholic fermentation and aging. After fermentation was complete, the pH levels in the four wines were in a similar range (3.43-3.52), while total acidity levels ranged from 9.98 to 16.2 g/L, which were significantly different among the four wines. During 120 days of aging, the ethanol content ranged from 15.8 to 16.40% which corresponds to a good conversion rate of sugars. Among the four samples tested, the wine made with Jeongeup raspberries showed the highest levels of total phenolic content, and other color values such as hue and intensity. The predominant organic acids were citric acids (3.30-4.89 mg/mL) and succinic acids (1.92-3.48 mg/mL). Overall the wine made with Jeongeup raspberries showed differences in physico-chemical compositions compared to the other wines made with Gochang, Hoengseong, and Sunchang raspberries, respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.266-272
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• 1997

In order to investigate the compression and decompression properties of cucumber, radish, garlic, ginger and potato, edible parts of samples were prepared to size of ${\Phi}\;5\;mm{\times}H\;5\;mm$, and force deformation relationship during application and removal of force were observed. Compositions of sample and cell characteristics were measured, and correlations between them were investigated. Deformation rate was large in initial stage of compression and decreased afterward, but the reverse trends were observed in the decompression. The time and deformation to 9 N were large of 5.30 sec and 1.344 mm in potato, and small of 4.62 sec and 0.896 mm in garlic, respectively. Force(y)-deformation(x) curve between compression and decompression were clearly showed hysteresis loop and relationship of x and y were as follows: y=esp (a+b log(x)). The maximum work was $3.888{\sim}5.099{\times}10^{-3}\;J$ for potato in compression and $2.09{\times}10^{-3}\;J$ for garlic in decompression. Irrecoverable work were large as $77{\sim}96%$ in cucumber, radish and potato, and small as $36{\sim}42%$ in garlic. Compression deformation were large as $1.016{\sim}1.344\;mm$ in potato, and small as $0.656{\sim}0.896\;mm$ in garlic. Degree of elasticity were large as $0.756{\sim}0.777$ in garlic, and small as $0.301{\sim}0.465$ in radish and potato. Compression and decompression characteristic values were showed high correlation with moisture, viscosity of juice, ceil size, density and regularity.

• Journal of the Korean Vacuum Society
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• v.16 no.1
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• pp.27-32
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• 2007

We have investigated photoluminescence(PL) spectra of four $In_xGa_{1-x}N(x=0.15)/GaN$ multiple quantum well(MQW) structures with different well widths in order to study a phenomenon on crystal phase separation. The asymmetic behavior of PL spectra becomes stronger with increase of the well width from 1.5 nm to 6.0 nm, which indicates dual-peak nature. Analyzing the dual-peak fit PL spectra, we have observed that the intensity of low-energy shoulder peak rapidly becomes stronger, compared to that of high-energy peak corresponding to a transition in InGaN QW. It suggests that InGaN QW has two phases with tiny different In compositions, and that In-rich(InN-like) phase forms more and more relatively than stoichiometric InGaN(x=0.15) phase by the InN phase separation mechanism as the QW width increases. PL spectrum of 6.0-nm sample shows an additional peak at low-energy lesion(${\sim}2.0\;eV$) whose energy position is almost the same as a defect band of yellow luminescence frequently observed in GaN epilayers. It may be due to a defect resulted from In deficiency formed with development of the phase separation.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.255-259
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• 2007

For this investigation, we analyzed the chemical characteristics and enzyme activities of Icheon Ge-Geol radish, Gangwha turnip, and Korean radish. Regarding their proximate compositions, the water contents of the Icheon Ge-Geol radish, Gangwha turnip, and Korean radish were 87.78, 92.73, and 91.45%, respectively. The crude protein, crude fiber, and ash contents of the Icheon Ge-Geol radish were 1.35, 1.11, and 1.55%, respectively, which were much higher than the contents of the other samples; however, total dietary fiber was significantly lower. For mineral content, the magnesium, potassium, and calcium levels of the Icheon Ge-Geol radish were higher than the other samples. With regards to the enzyme activities of the samples, the protease and myrosinase activities of the Icheon Ge-Geol radish were higher than in the other samples. For ${\alpha}-amylase$ activity, the Korean radish showed the strongest activity (18.99 units/g of sample), followed by the Gangwha turnip and Icheon Ge-Geol radish.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.549-556
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• 1993

To obtain a basic data of Korean geoduck(Panope japonica A. Adams) for fast food manufacturing, contents of proteinous compounds, nucleic acid and related compounds were analysed, and monthly changes of proximate compositions and freshness changes during frozen storage have been studied. The edible portions were $29.92\%$ in 3 years old samples and $38.04\%$ in 5 years old ones, respectively. The moisture and protein content showed the highest level from March to April and those of lipid and glycogen showed the highest level in July. Taurine, glycine, alanine and glutamic acid were the major free amino acid in 5 years old samples harvested in July and taurine content showed the highest level among free amino acids. Glutamic acid was the most abundant amino acid among the amino acids of protein hydrolyzate in 5 years old sample(96.6mg/16g-N). Leucine and lysine were revealed as relatively higher content(8.35 and $7.70\%$). From the analytical results on VBN, TMAO, TMA and $NH_2-N$, blanching at $95^{\circ}C$ for 2 mins was effective to maintain the quality of geoduck during frozen storage. Total creatine content was not changed in blanched geoduck.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.118-122
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• 1987

In order to find the effect of the storage time on the characteristics and sterol composition of the sesame seed, the characteristics, unsaponifiable matters, fractionation pattern of sterol and sterol compositions of 4-desmethylsterol on the sesame seed oil were analysed at the harvest time and after 56 months storage. The sample seed was kept in cotton bag within the natural dark store room. The oil content was decreased from 50.3g per 100g sesame seed at harvest time to 45.5g at 56 months stored. The acid value was increased sharply from 1.8 to 13.4 during the storage of sesame seed and iodine value was increased small, but saponification value and refractive index were hardly changed. The amount of unsaponifiables from 24.3mg to 20.9mg per gram on basis during storage time, and the 4,4-dimethylsterol and 4-monomethylsterol from unsaponifiables were decreased, otherwise, 4-desmethylsterol was increased. In the changes of sterol composition in the 4-desmethylsterol fraction from unsaponifiables, the compesterol and stigmasterol content were not nearly changed, otherwise, the sitosterol content was decreased from 51.0% to 48.2%, but the content of ${\Delta}^5-avenasterol$ was increased from 15.2 % to 18.4% during the storage of sesame seed within 56 months.

• Tuberculosis and Respiratory Diseases
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• v.79 no.3
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• pp.165-178
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• 2016

Background: Although recent metagenomic approaches have characterized the distinguished microbial compositions in airways of asthmatics, these results did not reach a consensus due to the small sample size, non-standardization of specimens and medication status. We conducted a metagenomics approach by using terminal restriction fragment length polymorphism (T-RFLP) analysis of the induced whole sputum representing both the cellular and fluid phases in a relative large number of steroid $na{\ddot{i}}ve$ asthmatics. Methods: Induced whole sputum samples obtained from 36 healthy subjects and 89 steroid-$na{\ddot{i}}ve$ asthma patients were analyzed through T-RFLP analysis. Results: In contrast to previous reports about microbiota in the asthmatic airways, the diversity of microbial composition was not significantly different between the controls and asthma patients (p=0.937). In an analysis of similarities, the global R-value showed a statistically significant difference but a very low separation (0.148, p=0.002). The dissimilarity in the bacterial communities between groups was 28.74%, and operational taxonomic units (OTUs) contributing to this difference were as follows: OTU 789 (Lachnospiraceae), 517 (Comamonadaceae, Acetobacteraceae, and Chloroplast), 633 (Prevotella), 645 (Actinobacteria and Propionibacterium acnes), 607 (Lactobacillus buchneri, Lactobacillus otakiensis, Lactobacillus sunkii, and Rhodobacteraceae), and 661 (Acinetobacter, Pseudomonas, and Leptotrichiaceae), and they were significantly more prevalent in the sputum of asthma patients than in the sputum of the controls. Conclusion: Before starting anti-asthmatic treatment, the microbiota in the whole sputum of patients with asthma showed a marginal difference from the microbiota in the whole sputum of the controls.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.513-517
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• 2013

We investigated the properties of impregnated activated carbons, a commercial adsorbent for the individual protection equipment, and examined CO adsorption and oxidation to $CO_2$. The surface area, pore volume and pore size were measured for four commercial samples using Brunauer-Emmett-Teller/Barrett-Joyner-Halenda (BET/BJH), and atomic compositions of the sample surface were analyzed based on SEM/EDS and XPS. Impregnated activated carbons containing Mn and Cu for fire showed the catalytic CO oxidation to $CO_2$ with a high catalytic activity (up to 99% $CO_2$ yield), followed by the CO adsorption at an initial reaction time. On the other hand, C: for chemical biologial and radiological (CBR) samples, not including Mn, showed a lower CO conversion to $CO_2$ (up to 60% yield) compared to that of fire samples. It was also found that a heat-treated activated carbon has a higher removal capacity both for CO and $CO_2$ at room temperature than that of untreated carbon, which was probably due to the impurity removal in pores resulted in a detection-delay about 30 min.

• Journal of the Korean Chemical Society
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• v.35 no.2
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• pp.99-104
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• 1991

Nonstoichiometric solid solutions of Sr$_{1+x}Er _{1-x} FeO _{4-y}$ system (x = 0.00, 0.25, 0.50, 0.75 and 1.00) with layered $K_2NiF_4$ type structure were prepared at 1350$^{\circ}$C under atmospheric pressure. By the analysis of X-ray diffraction, the crystallographic structures of the solid solution of all compositions were found to be pseudo-tetragonal system. Nonstoichiometric chemical formulas have been determined by Mohr salt analysis. It shows that the amount of Fe$^{4+}$ increases with increasing x up to 0.50 and then decreases, and the value of oxygen nonstoichiometry increases with increasing x value. Mixed valency states of Fe$^{3+}$ and Fe$^{4+}$ in the sample were identified again by Mossbauer spectroscopic analysis at 298 K. Electrical conductivity varied within the semiconductivity range of 10-2 ∼ 10-7(${\Omega}$-1cm-1), activation energy for electrical conduction decreased with the increment of the mole ratio of Fe$^{4+}$ or ${\tau}$ value. The conduction mechanism could be explained by the hopping model of the conduction electrons between the valency states of Fe$^{3+}$ and Fe$^{4+}$.

• The Journal of the Petrological Society of Korea
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• v.14 no.3 s.41
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• pp.141-148
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• 2005

Lead isotopic compositions are analyzed from the sulfide minerals of the Yeonhwa, Janggun and Uljin deposits and from host limestone, intrusives, and basement rocks to reveal the source of Pb in these deposits. In the $^{206}Pb/^{204}Pb$ vs $^{207}Pb/^{204}Pb$ plot, Galenas from the Yeonhwa mine display relatively well defined positive linear array, similar to the Precambrian basement rocks of the Korean peninsula. A galena sample from the Uljin mine, Janggun limestone and the basement rocks also follow the variation of Yeonhwa mine. However, ore minerals from the Janggun mine, having relatively low $^{206}Pb/^{204}Pb$ values, reveal offset from such trend toward lower $^{207}Pb/^{204}Pb$ values. Considering the fact that Mesozoic igneous rocks and ores within the Gyeongsang basin display considerably lower $^{207}Pb/^{204}Pb$ values than basement rocks of the Korean peninsula, the deviation of Janggun ore minerals can be interpreted as to reflect mixing between leads from old continental crustal materials and from Mesozoic igneous rocks with more mantle signature. The lead of the Yeonhwa and Uljin mine, following trend of Precambrian basement rather well, seems to have been originated mostly from such basement. However, regarding that they occupy low $^{207}Pb/^{204}Pb$ side of the variation trend of the basement, the possibility of having some leads derived from the Mesozoic igneous rocks cannot be excluded.