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A Characteristics and Distributions of Wet Deposition in Korea, 2005 (2005년 우리나라 습성강하물의 특성과 분포)

  • Han J.S.;Lee S.D.;Hong Y.D.;Kong B.J.;Shin S.A.;Jung I.R.
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.4
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    • pp.459-467
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    • 2006
  • This study was carried out to characteristics and distributions of acid deposition in Korea. Precipitation was collected by acid deposition monitoring networks and analyzed for pH, conductivity, and following major ionic components $SO_4^{2-}$, $CI^-$, $NO_3^-$, $NH_4^+$, $Na^+$, $K^+$, $Ca^{2+}$, $Mg{2+}$. During the investigation period, Volume weighted annual mean pH of precipitation in Korea is 4.8, showing slightly acidic level. The amount of rainfall in the range of pH 5.1$\sim$5.5 charged approximately 28% of annual precipitation,23.4% in pH 4.6$\sim$5.0, and contributed 16.2% under pH 4.5. Among seasons, alkaline precipitation has occurred more often in spring, meanwhile acidic precipitation in which pH is under 4.5 has frequently occurred in autumn. Volume weighted annual mean concentrations of $SO_4^{2-}$, $NO_3^-$, $CI^-$ are 2.558 mg/L, 1.590 mg/L, 1.286 mg/L respectively, and provided that $SO_4^{2-}$, is the major contributor, followed by $NO_3^-$, $CI^-$. In case of cation, annual mean concentration for $NH_4^+$, $Na^+$, $K^+$, $Ca^{2+}$, $Mg{2+}$, $H^+$ are 0.693 mg/L, 0.528 mg/L, 0.439 mg/L, 0.455 mg/L, 0.089 mg/L,0.015 mg/L, and $NH_4$ were decided as the main contributor, followed by $Na^+$, $K^+$, $Ca^{2+}$, $Mg{2+}$, $H^+$. Annual wet deposition rate for sulfate, nitrate and ammonia are $3.316gm^{-2}yr^{-1}$, $2.057gm^{-2}yr{-1}$, $0.894gm^{-2}yr{-1}$, respectively, and it was founded that the deposition flux in summer contributes about 38.42% to 67.62% to total deposition.

Characteristics of dibenzothiophene desulfurization by mutant Gordona sp. EID (돌연변이 균주 Gordona sp. EID의 dibenzothiophene 탈황 특성)

  • Cho, Kyung-Suk;Kim, Yoon Jung;Sung, Jung Hyeon;Ryu, Hee Wook;Chang, Yong Keun
    • Clean Technology
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    • v.5 no.2
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    • pp.79-86
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    • 1999
  • Mutant strain EID was developed by treating Gordona sp. CYKS1 with ethylmethanesulfone, and the desulfurization characteristics of dibenzothiophene(DBT) by mutant EID was investigated. Strain EID desulfurized DBT to 2-hydroxybiphenyl (2-HBP) by 4S pathway. Desulfurization rate of the strain EID was $4.0{\mu}mol{\cdot}L^{-1}{\cdot}h^{-1}$, while that of the wild type CYKS1 was $2.6{\mu}mol{\cdot}L^{-1}{\cdot}h^{-1}$. The effect of glucose concentration supplied as the carbon source on the DBT desulfurization showed that DBT desulfurization rate was enhanced as the glucose concentration increased. Maximum DBT desulfurization rate was $11.1{\mu}mol{\cdot}L^{-1}{\cdot}h^{-1}$ at 2.0 mM DBT concentration. As end-products such as 2-HBP and sulfate concentrations increase, DBT desulfurization activity of the strain EID decreased. When 0.2 mM of 2-HBP was added in the medium, no growth and desulfurization activity was observed. When 0.5 g/L $Na_2SO_4$ was simultaneously supplied with DBT, DBT desulfurization rate was$1.4{\mu}mol{\cdot}L^{-1}{\cdot}h^{-1}$.

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Production of Acetate from Waste Gas using Peptostreptococcus productus (Peptostreptococcus productus를 이용한 산업체 부생가스로부터 아세테이트 생산)

  • 강환구;전희진
    • KSBB Journal
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    • v.15 no.2
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    • pp.188-194
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    • 2000
  • The anaerobic bacterium P. productus was known to produce acetate from CO, C02 and H2. In this research the acetate f formation from waste gas was studied. For this research, kinetic parameter study on CO conversion were carried out. From t this study maximum CO conversion rate of 39.3 mmol/L . hr . 0.0 and Km of 0.578 atm were obtained. Also the effect of c CO refreshment, N source, initial pH and c비ture temperature on acetate formation were studied. Acetate formation in 5L lab s scale fermenter was tested and specific acetate production rate of 0.48 g/L-hr-O.O. was obtained and the acetate c concentration was 21 g/L.

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Interaction between Nutrient Density Diets and Sex on Carcass and Quality Characteristics in Finishing Pigs (사료의 영양소 수준과 성별이 도체 및 육질특성에 미치는 영향)

  • Ha, Y.J.;Lee, J.I.;Lee, J.Y.;Lee, J.W.;Jung, J.D.;Kwack, S.J.;Song, Y.M.;Do, C.H.
    • Journal of Animal Science and Technology
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    • v.47 no.1
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    • pp.57-72
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    • 2005
  • The present study was undertaken to investigate the effects of nutrient density diets and sex on carcass and pork quality characteristics in finishing pigs. A total of 96 pigs(58.04 $\pm$ 6.85 kg) were divided into 2 groups(gilts and barrows), each sex group was assigned to 3 nutrient density(high : 18.5%, middle : 16.0% and low: 14.0% CP, respectively) and raised up to 1l0kg live weight. Each treatment had four replicates with three or five pigs per replicate. The treatments comprised the feeding regimes of 1) the low density diet for 60 days, 2) the middle nutrient density diet for the 30 days followed by a low nutrient density diet for the remaining 30 days and 3) the high nutrient density diet for the 30 days followed by a middle nutrient density diet for the remaining 30 days. Pigs were conventionally slaughtered, and then chilled overnight. Carcass characteristics and grades were determined on those carcasses, and pork loin muscle was removed from each left side at 5th to 13th rib for quality evaluation were evaluated. There were no differences in the carcass weight between sex and nutrient density. Dressing percent of L-L(gilts) treatment was significantly higher than that of other treatments(P< 0.05). Barrows showed a thicker back fat thickness than gilts. There were no difference in intramuscular fat, subcutaneous fat and springiness between sex and nutrient density. Intermuscular fat of barrows groups was significantly higher than the gilts groups(P < 0.05). In the meat quality characteristics, there were no difference in general composition, meat and fat color between sex and nutrient density. pH of L-L(gilts) treatment was significantly higher than that of other treatments(P < 0.05). Cooking loss and shear force value of H-M(barrows) treatment were significantly higher than those of other treatments(P< 0.05). Purge loss of barrows groups was significantly higher than the gilts groups(P < 0.05). Myoglobin content of H-M treatment was significantly lower than L-L and M-L treatments(P< 0.05). Texture of H-M treatment was higher than L-L and M-L treatments. The content of myristic, palmitic, palmitoleic and oleic acid were significantly higher in the barrows groups(P< 0.05). However, stearic, linoleic and arachidonic acid were significantly higher in the gilts(P < 0.05). Amino acid content of L-L treatment was significantly higher than M-L and H-M treatments(P < 0.05). In conclusion, carcass and pork quality characteristics were affected by sex and nutrient density.

Preparation and Characteristics of Curd Yogurt from Milk Added with Purple Sweet Potato (자색고구마를 첨가한 호상요쿠르트의 제조와 특성)

  • 이주찬;이가순;이종국;한규흥;오만진
    • Food Science and Preservation
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    • v.6 no.4
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    • pp.442-447
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    • 1999
  • A curd yogurt was prepared by fermenting milk added with skim milk powder and purple sweet potato by culture of 5 types of lactic acid bacteria(Lactobacillus delbruekii sub. sp. lactis, Streptococcus lactis, acidity, number of viable cell, stability of purple sweet potato's pigment and keeping qualify. Among the organisms tested, the acid production and number of viable cell by the culture of L bulgaricus remarkably increased for the first 12 hem which showed 1.04${\times}$10$\^$9/ CFU/mL in number of viable cell and 4.22 In pH where as fermentation by the culture of B. bifidum was slow. After 36 hours of incubation which showed 3.3 ${\times}$ l0$\^$8/ CFU/mL in number of viable cell and 5.1 in pH. In stabilities of purple sweet potato anthocyanin pigment n fermentation, yogurt by B. bifidum was found to be most stable followed by Leuc. lactis, L. delbruekii sub. sp. lactis, L bulgaricus, but yogurt by St. lactis was not stable. When curd yogurt added with Purple sweet Potato was kept at 2∼3$^{\circ}C$ for 14 day, its keeping quality(pH, titratable acidity, number of viable cell) was relative good except product by L. bulgaricus was found to be decreased most of viable cell. After 2 weeks of keeping, pigment of yogurt was decreased by B. bifidum, stable by L. delbruekii sub. sp. lactis.

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L-라이신 발효에 있어서 당밀전처리의 영향

  • Shin, Hyun-Chul;Kim, Seong-Jun;Sung, Jin-Suck;Jeon, Yeong-Joong;Lee, Jae-Heung
    • Microbiology and Biotechnology Letters
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    • v.24 no.3
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    • pp.376-379
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    • 1996
  • Cane molasses, the most widely used carbon source for the industrial fermentation of L-lysine, usually contains a high concentration of calcium ions which tend to cause scaling problem in the recovery process. To remove the calcium ions, cane molasses was pretrea ted with sulfuric acid by adjusting the pH to 2.5-3.5. When the pretreated solution was directly heat-sterilized and used in the fermentation, a significant reduction in L-lysine production was observed. In this paper, we proved that sucrose is a superior substrate for L-lysine fermentation to that of glucose or fructose and that the above-mentioned decrease of L-lysine production was caused by the hydrolysis of sucrose in the molasses when the molasses was heat-sterilized at a low pH. The problem was overcome by adjusting the pH of molasses to neutral before sterilization.

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Glucose를 기질로 한 Rhodospirillum rubrum KCTC-1372 의 수소생산

  • Park, Jun-Seong;Lee, Sang-Muk;Park, Gi-Yong;Kim, Cheol-Gyeong;Kim, Nam-Gi
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.277-280
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    • 2000
  • Rhodospirillum rubrum KCTC 1372 produced hydrogen from glucose for first 48hrs culture under the anaerobic photosynthetic conditions, and after 48hrs culture the hydrogen production was decreased by the accumulation of producing organic acids in broth. Only 41% of glucose was consumed and 143mL/day/L hydrogen were produced after 96hrs culture. However the hydrogen production and glucose consumption were substantially increased when the pH of the culture broth were controlled to 6.8-7.2. After 96hrs culture, 450mL/day/L hydrogen were produced, and about 80% glucose was consumed. Specific hydrogen production rate was 48.33mL/hr/g cells under pH not controlled, but 45.42mL/hr/g cells under pH controlled.

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A Study on the Variation of Nutrients and Water Quality in Suk Chon Lake (石村湖의 營養鹽類 및 수질의 動態에 관한 조사연구)

  • Choi, Han-Young;Kim, Tai-Jeon;Park, Sung-Bae
    • Journal of Environmental Health Sciences
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    • v.14 no.1
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    • pp.47-53
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    • 1988
  • This study was performed to investigate a seasonal and vertical variation of the nutrients, water temperature, pH, DO, BOD, COD in Sukchon lake from May 1985 to Jan. 1986. The results were as follows. 1. Vertical descent of water temperature was the remarkable situation on Jul. and difference between surface layer and bottom layer was 3.5$\circ$C. 2. The value of pH was average 8.0 in both lake. The value of pH in the winter was average 7.6, and Summer was average 8.3. 3. The contents of dissolved oxygen was the highest value (13.0mg/l in surface layer on Jan. and the lowest value (8.1mg/l in bottom layer on Ul. 4. The contents of PO$_4$-P, NH$_3$-N, NO$_3$-N and T-N were 0.03~O.17mg/l 0.12~0.34mg/l 0.36~0.91mg/l and 0.76~1.37mg/l respectively.

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Volatiles from the Maillard Reaction of L-Ascorbic Acid and L-Alanine at Different pHs

  • Yu, Ai-Nong;Deng, Qi-Hui
    • Food Science and Biotechnology
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    • v.18 no.6
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    • pp.1495-1499
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    • 2009
  • The volatiles formed from the reactions of L-ascorbic acid with L-alanine at 5 different pH (5, 6, 7, 8, or 9) and $140{\pm}2^{\circ}C$ for 2 hr was performed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis were identified to be 25 different kinds. The reaction between L-ascorbic acid and L-alanine led mainly to the formation of pyrazines. Many of these were alkylpyrazines, such as 3-ethyl-2,5-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine, 3,5-diethyl-2-methylpyrazine, methylpyrazine, 2-ethyl-6-methylpyrazine, and 2,3-diethyl-5-methylpyrazine, other compounds identified were furans, phenols, benzoquinones, 2,4,6-trimethylpyridine, and 2-methylbenzoxazole. The studies showed that furans, such as furfural and benzofuran were formed mainly at acidic pH. In contrast, higher pH values could promote the production of pyrazines.

IDEAL RIGHT-ANGLED PENTAGONS IN HYPERBOLIC 4-SPACE

  • Kim, Youngju;Tan, Ser Peow
    • Journal of the Korean Mathematical Society
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    • v.56 no.4
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    • pp.1131-1158
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    • 2019
  • An ideal right-angled pentagon in hyperbolic 4-space ${\mathbb{H}}^4$ is a sequence of oriented geodesics ($L_1,{\ldots},L_5$) such that $L_i$ intersects $L_{i+1},i=1,{\ldots},4$, perpendicularly in ${\mathbb{H}}^4$ and the initial point of $L_1$ coincides with the endpoint of $L_5$ in the boundary at infinity ${\partial}{\mathbb{H}}^4$. We study the geometry of such pentagons and the various possible augmentations and prove identities for the associated quaternion half side lengths as well as other geometrically defined invariants of the configurations. As applications we look at two-generator groups ${\langle}A,B{\rangle}$ of isometries acting on hyperbolic 4-space such that A is parabolic, while B and AB are loxodromic.