• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.25-32
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• 2014

This study aimed to analyze the general ingredients and volatile compounds of ipguk (koji) and nuruk soju distilled under reduced pressure (RP) or atmospheric pressure (AP) conditions. After the secondary brewing process, soju made using ipguk had a final fermentation alcohol content of $18.0{\pm}0.6%$, whereas soju made using nuruk reached $14.3{\pm}1.7%$. The level of succinic acid was the highest in ipguk soju ($7,685.33{\pm}34.97$ ppm), but nuruk soju also showed a high level of succinic acid ($5,945.79{\pm}76.30$ ppm) after its final fermentation. In an analysis of fusel alcohol content, the level of n-propanol in ipguk soju (389.10-397.27 ppm) was similar under different RP (50 cm Hg and 60 cm Hg) and AP conditions ($80^{\circ}C$ and $90^{\circ}C$). Under RP and AP conditions, the isoamyl alcohol/isobutanol (A/B) ratio was similar, ranging from 1.32-1.35. In ipguk soju distilled under RP conditions of 50 cm Hg and 60 cm Hg, the amount of the toxic component, acetaldehyde, was 8.59 and 9.27 ppm, respectively. Under AP conditions, the amount of acetaldehyde in ipguk soju distilled at 80 and $90^{\circ}C$ was 9.80 and 10.63 ppm, respectively, indicating that the amount of acetaldehyde did not differ depending on the distilling method used. These results suggest that the liquor distilled from the mash produced using ipguk under RP conditions may be of a higher quality.

• Journal of Microbiology and Biotechnology
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• v.32 no.12
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• pp.1553-1560
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• 2022

A Gram-stain-negative, rod-shaped bacterial strain, JC4^T, was isolated from a freshwater sample and determined the taxonomic position. Initial identification based on 16S rRNA gene sequences revealed that strain JC4^T is affiliated to the genus Mucilaginibacter with a sequence similarity of 97.97% to Mucilaginibacter rigui WPCB133^T. The average nucleotide identity and digital DNA-DNA hybridization values between strain JC4^T and Mucilaginibacter species were estimated below 80.92% and 23.9%, respectively. Strain JC4^T contained summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c) and iso-C_15:0 as predominant cellular fatty acids. The dominant polar lipids were identified as phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid, and two unidentified lipids. The respiratory quinone was MK-7. The genomic DNA G+C content of strain JC4^T was determined to be 42.44%. The above polyphasic evidences support that strain JC4^T represents a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter aquariorum sp. nov. is proposed. The type strain is JC4^T (= KCTC 92230^T = LMG 32715^T).

• Journal of Environmental Science International
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• v.9 no.4
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• pp.275-284
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• 2000

The studyies on physico-chemical factors and phytoplankton at the 3 rivers in the Taejon city were conducted from November 1997 to May 1998. The Results were as floows; In the water quality, the down streams were generally worse than the upper streams. Water temperature was varied from 2.4$^{\circ}C$ to 23.$0^{\circ}C$; DO from 1.80mg/$\ell$ to 17.6mg/$\ell$ ; pH from 4.7 to 10.4 ; BOD from 0.78mg/$\ell$ to 8.80mg/$\ell$ ; COD from 0.32mg/$\ell$ to 8.26mg/$\ell$ ; SS from 2.0mg/$\ell$ to 43.0mg/$\ell$ ; total phosphate was from 0.001mg/$\ell$ to 0.709mg/$\ell$ ; total nitrogen 0.01mg/$\ell$ to 11.69mg/$\ell$. In phytoplankton species, they were identified as total 191 taxa composed of 8 classes, 18 orders, 35 families, 74 genera, 152 species, 35 varieties and 4 forms. The dominant species were Synedra ulna in Taejon-chon, Diatomavulgare in Yudong-chon, Oscillatioria princeps, Scenedesmus qadricauda, Synedra ulna, and Diatom vulgare in Gap-chon. Standing crops of phytoplankton were from 2,076 cells/$m\ell$ to 97,356 cells/$m\ell$

• Journal of Microbiology
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• v.34 no.3
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• pp.274-278
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• 1996

Two peptides, MA-inv AND MA-ME, with the sequence 10-17 of maganin 2 at their-N-termini were designed and synthesized. The peptides had higher antifungal activities against Aspergilus fumigatus without hemolytic activities. The minimal inhibition concentratory (MIC) values of both peptides against A. fumigatus were 5 .mu.g/ml, whereas those of the native peptides, magainin 2 and melittin, were 10.mu.g/ml. At 3 .mu.g/ml, MA-inv and MA-ME inhibited the mycelium growth of A. fumigatus by 94.6% and 97.3% respectively, whereas magainin 2 and melittin inhibited by 62.2% and 32.4, respectively. MA-inv showed up to 80% inhibition of (1, 3)-.betha.-D-glucan synthase activity of A. fumigatus. The peptides also showed up to 80% inhibition of (1, 3)-.betha.-D glucan synthase activity of A. fumigatus. The peptides also showed antifungal activities for other fungi of Aspergillus sp. However, the antibiotic activities of MA-ME against Escherichia coli, Bacillus subtilis and Fusarium oxysporum were more effective than those of MA-inv, suggesting that the C-terminal sequences of MA-inv and MA-ME may also influence their antibiotic activities. These results suggest that the N-terminal sequence of the designed peptides, KKFGKAFV, is important for their antifungal activities against A. fumigatus and their C- terminal sequences are related to the organism selectivity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.360-366
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• 2001

Flour physicochemical properties of six Korean waxy wheat lines and their parental plants, including Kanto 107 and BaiHuo, which have partially null in GBSS (granule bound starch synthase), were evaluated in this study. The very low amylose content (3.20%) of Korean waxy wheat lines, which had been influenced by the null in all three GBSS isoforms encoded by three Wx loci, could result in the higher starch swelling power (25.15%), lower starch and flour pasting temperature (61.37$^{\circ}C$; 65.85$^{\circ}C$), and higher starch pasting peak viscosity and breakdown (246.60 RVU; 161.50 RVU) than those of their parental plants. In addition to high swelling and pasting properties, Korean waxy wheat lines had the higher protein content (12.80%), alkaline water retention capacity (97.39%), SDS sedimentation volume (80.33 $m\ell$) and damaged starch content (4.35 %) than those of their parental plants.

• Korean Journal of Materials Research
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• v.6 no.11
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• pp.1113-1120
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• 1996

다이아몬드 박막을 이용한 반도체소자를 실현시키기 위해서는 다이아몬드가 아닌 다른 재료의 기판위에 대면적에 걸쳐 다이아몬드막을 에피텍셜 성장시키는 것이 필수적이다. 그러나 이 분야의 연구는 아직 초보상태로 그 목표가 실현되지 못하고 있다. 본 논문에서는 저압의 ECR 마이크로파 플라즈마 CVD에 의하여 대면적의 Si(100)기판상에 방향성을 갖는 다이아몬드막을 성공적으로 성장시킨 결과를 보고자한다. 지금까지 얻어진 최적 핵생성 공정조건은 다음과 같다 : 반응압력 10Pa, 기판온도 80$0^{\circ}C$(마이크로파 전력이 3kW일 때), 원료가스 CH4/He 계로 농도비 3%/97%, 가스총유량 100sccm, 바이어스 전압 + 30V, 마이크로파 전력(microwave power)4kW, 바이어스 처리 시간 10분간이며, 성장단계에서의 증착공정 조건은 기판온도 80$0^{\circ}C$, 원료가스 CH4/CO2/H2계로 농도비 5%/15%/85%, 가스 총유량 1000sccm, 바이어스 전압 +30V, 마이크로파 전력 5kW, 성막시간 2시간으로 일정하게 유지하였다. 이 조건하에서 기판 면적 3x4$\textrm{cm}^2$의 대면적에 대해서 약 2x109cm-2의핵생성 밀도를 균일하게 재현성있게 얻었다. 원료가스로 CH4/H2를 사용한 경우보다 CH4/H2를 사용할 경우에 라디칼밀도의 증가에 의하여 더 높은 핵생성밀도를 얻을 수 있었다. 또한 저압의 ECR플라즈마 CVD의 경우에는 양의 바이어스전압이 막의 손상이 없어 다이아몬드 핵생성에 더 적합하였다.

• Food Science and Preservation
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• v.12 no.2
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• pp.166-172
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• 2005

Response surface methodology (RSM) was applied to monitor the effects of steaming and roasting conditions of Polygonatum odoratum roots an total phenolics content, electron donating ability (EDA) and nitrite-scavenging ability (NSA) of the extract. In steaming and roasting processes based on the central composite design. with variations in steaming time $(60\~180\;min)$, roasting temperature $(110\~150\;min)$ and roasting time $(10\~50\;min)$, coefficients of determinations $(R^2)$ were 0.9356 (p<0.01) in total phenolics, 0.9578 (p<0.01) in EDA and 0.9436 (p<0.01) in NSA (pH 3.0). The maximum value of total phenolics was $2847.67\;mg\%$ at 135.59 min of steaming time, $143.84^{\circ}C$ of roasting temperature and 43.47 min of roasting time. The maximum value of EDA was $75.00\%$ in 108.98 min, $135.56^{\circ}C$ and 48.86 min. The maximum value of NSA (pH 3.0) was $87.38\%$ in 162.80 min, $143.88^{\circ}C$ and 31.97 min, respectively. Total phenolics content of the extract was influenced by heating conditions in the order of roasting temperature, steaming time and roasting time. While EDA and NSA were appreciably influenced by roasting time, followed by roasting temperature and steaming time.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.70-77
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• 2003

From March 1998 to August 2000, the phenological and morphometric changes of Zostera marina L. were examined at the Duksan Port in the eastern coast of Korea. Morphometric characteristics, phenological stage, shoot density, biomass of Z. marina population and environmental parameters were also measured. Nutrient levels in water column varied over the season. Morphometric characteristics of vegetative shoot changed with season; shoot heights ranged from 54.2 cm (March) to 100.0 cm (October). Reproductive shoots appeared from mid-March to early September of which the height was ranged from 97.8 cm (March) to 213.0 cm (July). The flowering phase started at 12$^{\circ}C$ and the fruit development was resulted up to 21$^{\circ}C$. The seed maturing was developed at 22$^{\circ}C$-$25^{\circ}C$. Shoot density and biomass in permanent quadrate (0.25 m$^2$) were significantly different among seasons ranging from 38 to 136 shoots (mean 80.3$\pm$6.5) for shoot density, and 190 g dry wt m$^{-2}$ in October 1998 to 922 g dry wt m$^{-2}$ in June 1998 for biomass respectively. Relationships between shoot morphometrics and physico-chemical parameters were not significantly correlated. Seasonal changes in water temperature seemed responsible for the replacement of reproductive phases and the annual changes of shoot morphometrics in Z. marina populations.

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.9-17
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• 1989

This study was carried out in order to study the emulsifying properties of kidney bean protein isolate. Kidney bean protein isolate was tested for the purpose of finding out the effect of pH, addition of NaCl, and heat treatment on the solbulity and emulsion capacity, emulsion stability, surface hydropobicity and emulsion viscosity. The results were summarized as follows. 1 The solubility of kidney bean protein isolate was affected by pH and showed the lowest value at pll 4.5 which is isoelectric point of kidney bean isolate. When the kidney bean protein isolate was heated, the highest value observed at pH 2 and pH 7 was 96.11%, 97.41% respectively. 2. The emulsion capacity of kidney bean protein isolate was not significantly different with each pH. With addition of NaCl, emulsion capacity decreased steadily. When heated thr highest value observed at pH 2 and pH 7 was 82.91 ml oil/100 mg protein ($60^{\circ}C$), 82.08 m1 oil/100 mg protein ($80^{\circ}C$) respectively. 3. The emulsion stability was significantly higher at pH 4.5 than that of pH 2 and pH 7 (p 0.05) When NaCl was added, emulsion stability was generally increased after 2hrs. When heated, the highest value observed at pH 2 and pH 7 was 21.25% ($80^{\circ}C$),23.7%($100^{\circ}C$) respectively after 2hrs. 4. Surface hydrophobicity increased sharply as 0.2 M NaCl was added to pH 4.5. When heated, the surface hydrophobicity increased as the temperature increased. 5. The highest value of emulsion viscosity was observed at pH 4.5 and pH 7 when 0.2 M NaCl was added. Under heat treatment, the highest value was 48,000 cps at pH 4.5 ($40^{\circ}C$). In the case of pH 7, the highest value was 105,000 cpa at $100^{\circ}C$.

• Journal of Powder Materials
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• v.14 no.2 s.61
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• pp.97-100
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• 2007

The magnetic alloys of Cu-Fe ($Cu_{50}Fe_{50},\;Cu_{80}Fe_{20}\;and\;Cu_{90}Fe_{10}$) were prepared by a mechanical alloying method and their structural and magnetic behaviors were examined by X-ray diffraction and Mossbauer spectra. The magnetization curves did not distinctly show the saturation at 70 kOe for the concentrated alloys of $Cu_{80}Fe_{20}\;and\;Cu_{90}Fe_{10}$. The Mossbauer spectrum of $Cu_{80}Fe_{20}$ at room temperature shows one Lorentzian line of the paramagnetic phase, whereas the Mossbauer spectrum of $Cu_{90}Fe_{10}$ consists of sextet Lorentzian line at room temperature and a centered doublet line. The Mossbauer spectra of $Cu_{90}Fe_{10}$ measured in the temperature ranges from 13 to 295 K, implies that $Cu_{90}Fe_{10}$ to consists of two magnetic phases. One superimposed sextet corresponds to the ferromagnetic iron in Cu and the other one indicates the superparamagnetic iron rich phase.