• Title/Summary/Keyword: $L_{10}$

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Coagulating effects of several eco-friendly coagulant materials favorable for vermicomposting sewage sludge (하수슬러지에 대한 지렁이처리법 적용에 유리한 몇 가지 친환경 응집물질의 하수슬러지에 대한 응집효과)

  • Bae, Yoon-Hwan;Park, Soon-Cheol
    • Journal of the Korea Organic Resources Recycling Association
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    • v.23 no.1
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    • pp.52-62
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    • 2015
  • Coagulating effects of eco-friendly coagulant materials such as zeolite, kaolinite, loess and chitosan upon sewage sludge were evaluated. And coagulating effects of the mixtures of those materials and polymer (polyacrylamide) were also investigated. Coagulating efficiency of loess was higher than that of kaolinite and zeolite at the treatment levels of 2,500~50,000mg/L. Coagulating efficiencies of zeolite, kaolinite and loess at the treatment level of 20,000mg/L were lower than that of 1,000 mg/L of polymer, which meant that single application of those materials in real plant were not feasible. At the treatment level of 1,000 mg/L, coagulating efficiency of Chitosan was much lower than that of polymer, which also meant that single use of chitosan in real plant could be unrealistic because of its high price. However, the application of the mixture of 'polymer 80mg/L + kaolinite or loess 500 mg/L + chitosn 10mg/L' or the mixture of 'polymer 80mg/L + kaolinite or loess 500mg/L' was promising way for coagulating sewage sludge.

In Vitro Propagation of Zantedeschia spp. through Shoot Tip Culture (경정배양에 의한 Zantedeschia spp.의 기내번식)

  • Han, Bong-Hee;Cho, Hae-Ryong
    • Journal of Plant Biotechnology
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    • v.30 no.1
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    • pp.59-63
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    • 2003
  • This experiment was conducted to propagate Zantedeschia spp. in vitro. The frequency of adventitious bud clusters (ABC) formation from shoot tips in Z. 'Best Gold' was high at more than 65% on media with 2.0∼5.0 mg/L BA or 0.1∼1.0 mg/L thidiazuron. The highest formation rate of ABC (75%) was obtained on medium containing 2.0 mg/L BA. Comparing to treatment of BA alone, combined one of BA and NAA did not stimulate the formation of ABC and the shoot regeneration from shoot tips. The proliferation of ABC from sections (0.7∼1.0 cm) of ABC occurred effective on medium with 2.0 mg/L BA. Shoots developed from the sections (0.7∼1.0 cm) of ABC grew and rooted favorably on media containing 1.0∼2,0 mg/L IBA. The shoots were multiplicated effectively on medium with 0.5 mg/L thidiazuron in Z. 'Childsiana', on medium with 3.0 mg/L BA in 2. 'Golden Affair', and on medium with 5.0∼10.0 mg/L BA in Z. 'Pacific Pink'.

Effect of continuous pulsed electric fields treatments on quality of apple juice (사과주스의 품질에 미치는 pulsed electric field 연속 처리효과)

  • Ahn, Seong-Hwan;Lim, Jeong-Ho;Kim, Young-Ho;Chung, Suk Jin;Park, Kee-Jai
    • Food Science and Preservation
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    • v.20 no.5
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    • pp.650-658
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    • 2013
  • Apple juices were sterilized by continuous pulsed electric field (PEF) treatments of pulse width of 25 ${\mu}s$ at electric field intensity of 20.0 kV/cm, and with the varied pulse frequencies of 35 Hz (40 kJ/L), 55 Hz (70 kJ/L), 72 Hz (100 kJ/L) and 85 Hz (130 kJ/L). The PEF treatments of apple juice reduced the microbial counts from 5.3 log CFU/mL of initial state to 3.0 log CFU/mL after PEF treatment at energy density of 130 kJ/L. Also yeast and fungi after PEF treatments were reduced from 5.3 log CFU/mL to 3.0 log CFU/mL and Escherichia coli were from 5.3 log CFU/mL of initial state to 4.7 log CFU/mL to < $10^1$ CFU/mL. The soluble solids and free sugars did not significantly differ (p<0.05) depending on conditions of PEF treatment. The total phenolic contents and antioxidant activity such as the DPPH and ferric reducing antioxidant power (FRAP) by PEF treatments were significantly partly reduced, but the PEF-reduced value came in smaller quantities than the heat treatment at $65^{\circ}C$. The iterative PEF treatments with pulse width of 25 ${\mu}s$ and pulse frequency of 85 Hz at electric field intensity of 20.0 kV/cm showed limited in microbial reduction. Also, total phenolic contents and antioxidant activity such as DPPH and FRAP, significantly decreased depending on treatment numbers of PEF (p<0.05).

Preparation and Structure of $[Ni(L)]I_2$ (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) ($[Ni(L)]I_2$ (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclo-tetradecane) 합작물의 합성 및 구조)

  • 최기영;김동원
    • Korean Journal of Crystallography
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    • v.8 no.2
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    • pp.119-123
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    • 1997
  • The complex [Ni(L)]I2 (1) (L:3,5,10,12-Tetramethly-1,4,8,11-tetraazacyclotetradecane) has been prepared and characterized by X-ray diffraction methods. The complex 1 crystallized in the orthorhombic system, space group Pcab with cell parameters a=13.293(1) Å, b=28.550(7) Å, c=10.804(1) Å, z=8. Least-squares refinement of 1 led to a R(Rw) factor of 0.043 (0.046) for 1851 observed reflections of Fo>3o (Fo). The crystal structure of 1 has a slightly distorted square-planar geometry and adopts the trans-III conformation.

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Chemical and Bacteriological Quality of Spring Waters in Pusan Area (부산시내 약수의 화학적 및 세균학적 수질에 관한 연구)

  • KIM Yong-Gwan;KOH Kwang-Bae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.2
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    • pp.169-175
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    • 1986
  • This study was carried out to evaluate the water quality of spring waters in Pusan area (see Fig. 1). In this experiment, one hundred and forty water samples were collected at 20 stations from July to December 1985. Range and mean value of constituents of the samples were as follows ; pH 6.2-8.2, 7.07 ; water temperature $4.0-23.5^{\circ}C,\;15.9^{\circ}C$ ; electrical conductivity $0.228{\times}10^{2}-2.125{\times}10^2{\mu}{\mho}/cm,\;0.860{\times}10^2{\mu}{\mho}/cm$; chloride ion 3.28-19.3mg/l, 6.81mg/l ; nitrite-nitrogen ND-0.221 mg/l, 0.017mg/l ; nitrate-nitrogen ND-6.779mg/l, 0.877 mg/l ; phosphate-phosphorus ND-0.105mg/l, 0.021mg/l ; silicate-silicious 2.12-22.70mg/l, 9.04mg/l, respectively. Especially, electrical conductivity, chloride ion, nitrite-nitrogen, nitrate-nitrogen, and silicate-silicious of the station 11 (Millakdong) were higher than those of others as $1.815{\times}10^2{\mu}{\mho}/cm$, 13.5mg/l, 0.076mg/l, 4.772mg/l and 14.07mg/l. Range and geometric mean value of total coliform and fecal coliform MPN's of the samples were 0-1,500/100ml, 13-470/100ml and 0-460/100ml, 2-32/100ml. Composition of coliform was $26.37\%$ Escherichia coli group, $21.98\%$ Citrobacter freundii group, $37.36%$ Entrobacter aerogenes group and $14.29\%$ others.

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Fermented Whey Produced by Mixed Culture of Lactobacillus acidophilus and Propionibacterium freudenreichii : Effect on Quality Properties of Bread (Lactobacillus acidophilus와 Propionibacterium freudenreichii로 혼합 배양한 Whey 발효물이 빵의 특성에 미치는 영향)

  • Yun Mi-Suk
    • The Korean Journal of Food And Nutrition
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    • v.18 no.2
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    • pp.109-114
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    • 2005
  • A mixed Lactobacillus acidophilus and Propionibacterium freudenreichii was cultured in the $10\%$ whey broth with $0.5\%$ yeast extract for 4 days. Viable cell numbers of Lactobacillus acidophilus and Propionibacterium freudenreichii were $2.4\ties10^9$ cfu/mL after 36hr and $9.42\times10^8$ cfu/mL after 96 hr. Consumption rate of lactose during fermentation was $87.5\%$. Propionic acid was produced 18.5g/L and acetic acid was produced 4.8g/L, as a result of that, comparison of propionic acid and acetic acid was 3.8:1 Volume of white pan bread was decreased as added amount of whey was increased. Hardess of white pan bread was decresed as added amount of whey was increased. Preservation period of white pan bread with $10\%$ whey fermented product elongated 2 day compared to control.

Survey on Canine Leptospiral Antibody Titer in Seoul (서울지역 견의 렙토스피라 항체가 조사)

  • 최준식;김성원;오영희;김성삼
    • Korean Journal of Veterinary Service
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    • v.14 no.1
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    • pp.1-5
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    • 1991
  • A serological survey for antibody of Leptospira spp. in canine was carried out from March to September, 1989 in Seoul. 182 serums collected from animal hospitals and keeping were collected and these were performed by using 12 different living antigens. In the microscopic agglutination test(MAT), being partial agglutination reaction at a serum dilution of 1:200 or over, we recorded it as positive. These results were compared with the species, sex and general conditions of canines, the areas and types of animal keeping. The results were summarized as followed ; 1. We detected the antibodies L. grippotyphosa 1 and L. icteroheamorrhagiae 1 in A area(total 48 heads ), L. canicola 1 and L. icterohaemorrhagiae 4 in B area(total 52 heads), L. hardjo 1 and L. icterohaemorrhagiae 2 in C area (total 32 heads), L. icterohaemorrhagiae 1 in D area(total 23 heads) L. grippotyposa 1 and L. icterohaemorrhagiae 2 in E area(total 27 heads) by MAT. There were positives for L. canicola 1, L. grippotyposa 2, L. hardjo 1 and L. icterohaemorrhagiae 10 in 5 areas by MAT. 2. The deteclive rate of leptospiral antibody in Jindo canine was 17.6% (3) among 17, Mixed 4.4% (4) among 90 and Exotic 9.3% (7) among 75 heads. 3. The Male(91 heads) was positive for 8.7%(8) and the female(91 heads) was positive for 6.5%(6). 4. In the vaccination, positive rate was 10.3% (7) among 55 heads, and in the unvaccination, positive rate was 5.5%(7) among 127 heads.

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Studies on Pollutant Concentrations in Ground Water and Their Behavior in Soils , Cheju Island. I. Changes in Nitrate-nitrogen Concentration in Ground-water near Hotel complexes and Business district During the Period form 1987 to 1992 (제주도 지하수중 오염물질의 농도와 토양중 그의 행동에 관한 연구 1. 호텔 및 상가주변에서의 지하수중 $NO_3-N$의 농도 변화 (1987-1992))

  • Hyun, Hae-Nam;Oh, Sang-Sil;Koh, Seung-Hak
    • Korean Journal of Environmental Agriculture
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    • v.13 no.1
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    • pp.19-30
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    • 1994
  • This study was conducted to investigate the degree of ground water pollution used for drinking water in Cheju Island. Samples were collected monthly from 31 wells of 10 divided areas and were analyzed for $NO_3-N$, pH, $SO_4$, Cl and hardness from 1987 to 1992. $NO_3-N$ concentrations in the samples, with the exception of sample No.23, did not exceed the standard concentration of drinking-water(10mg/l). $NO_3-N$ concentrations at area 10, unpolluted area, ranged from <1.0 mg/l to just over 1.2 mg/l. However, samples from the business district of the area 8 showed the concentrations ranging from 5 mg/l in 1987 to 8.l mg/l in 1992 with a mean of 6.8 mg/l, about 5 times higher than those from the area 10. $NO_3-N$ concentration in sample No. 23 increased from 4 mg/l in 1987 to 12.6 mg/l in 1991. Average rate of increase in $NO_3-N$ in samples of No. 1, 2, 4, and 8 at area 8 was about 1.2mg/l per year in the study period. The ground water at area 1, 2, 3, 4, 5, 6, and 7 showed in the range of pH 7 to 8.1, being similar to area 10. However, pH at area 8 was in the range of 6.6 to 7.3, being lower than that in the other areas. Hardness at area 1, 2, 3, 4, 5, and 6 were in the range of 30 to 80 mg/l, being higher than that at area 10. Those at area 8 were the highest among all the other areas tested. The results of this study suggest that $NO_3-N$ contamination in ground water could be a problem at hotel complexes and business district in Cheju Island.

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Extension of L-Fuzzy Topological Tower Spaces

  • Lee Hyei Kyung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.3
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    • pp.389-394
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    • 2005
  • The purpose of this paper is to introduce the notions of L-fuzzy topological towers by using a completely distributive lattic L and show that the category L-FPrTR of L-fuzzy pretopoplogical tower spaces and the category L-FPsTR of L-fuzzy pseudotopological tower spaces are extensional topological constructs. And we show that L-FPsTR is the cartesian closed topological extension of L-FPrTR. Hence we show that L-FPsTR is a topological universe.

Growth Kinetics and Sporulation of Bacillus thuringiensis in High Cell Density Culture (고농도 세포배양에서 Bacillus thuringiensis의 세포 성장과 포자 형성 속도)

  • 강병철;장호남
    • KSBB Journal
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    • v.16 no.1
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    • pp.30-35
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    • 2001
  • High cell density culture of Bacillus thuringiensis was conducted in fed-batch culture and TCRC using a bioreactor incorporating ceramic membrane filter. Cell growth of B. thuringiensis in fed-batch culture increased linearly, which was well matched by the results of cell growth modeling. In spite of the slower growth rate during fed-batch culture, no spore formation was observed, which was contrary to the results of continuous culture. Changing culture mode to batch culture after fed-batch operation induced a 2.7$\times$$10^9$ CFU/mL spore concentration using a 300 g/L glucose feed concentration. In TCRC operation incorporating ceramic filter within the bioreactor, the effect of glucose feed concentrations on the cell growth and spore formation of B. thuringiensis was determined. A maximum cell concentration of 1.8$\times$$10^{10}$ CFU/ml, which corresponds to 82.6 g-cell/L, was obtained in the TCRC using a 50 g/L glucose feed concentration. In the TCRC, cell growth increased linearly and glucose concentration was limited, which agreed well with the results of cell growth modeling. No spore formation was observed except when 1 g/L of glucose was fed. Changing to batch culture induced a 1.2$\times$$10^{10}$ CFU/mL of spore concentration, which was the highest spore concentration obtained among the various culture modes examined. The optimal glucose feed rate was found to be 0.55 g-glucose/h.

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