• Title/Summary/Keyword: L/D rate

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Discriminant Analysis of Cigarette Brands by Nearinfrared Spectroscopy (근적외선 분광법을 이용한 제품담배 판별 연구)

  • ;F.E. Barton
    • Journal of the Korean Society of Tobacco Science
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    • v.16 no.2
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    • pp.163-171
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    • 1994
  • This experiment was conducted to investigate the discrimination of cigarette brands and the similarity between Korea and America cigarette brands by near infrared spectra. Statistical tools such as principal component analysis (PCA) and mahalanobis distance(M.D) were used. The discrimination rate of the Korea and the America cigarette brands, determined by position number which was calculated with PCA and M.D, was 94% and 87%, respectively. The spectra of the 10 America cigarette brands were selected by averaging 5 sample spectra for each brand and another 5 spectra for each brand were investigated to use as the sample spectra. Comparing the sample spectra with the selected spectra by M.D using 410-1090 nm, 1110-1850 nm and 1970-2490 nm wavelength, the discrimination rate which was determined by the closest M.D between the sample and the selected spectra was 100% when each spectra was investigated on the same time. But the discrimination rate decreased 50% when the sample and the selected spectra were investigated on the different time. Excluding 1970-2490 nm wavelength, the discrimination rate increased up to 90% when the sample and the selected spectra were investigated on the different time. Comparing the spectra of Korea cigarette brands with those of America cigarette brands by M.D using only 410-1090 nm and 1110-1850 nm wavelength, the spectra of Expo(G) was similar to Winston, Vantage(U.L) and Benson & hedges(M.), the spectra of Hanaro(D) was similar to Carrel, Winston(L), Vantage(U.L), \Vantage and Carrel(L), the spectra of Hanaro(L) was similar to Winston(L) , Carton, Vantage and Carmel(L) and the spectra of Pinetree was similar to Kent, Kool, Kent(G.L), Merit and Benson & hedges(L), respectively. Key Words : NIRS, cigarette brands discrimination

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Malate Stimulation on Growth Rate of Leuconostoc oenos (Leuconostoc oenos의 생장률에 대한 사과산의 촉진 작용)

  • Lee, S.O.;Pack, M.Y.
    • Microbiology and Biotechnology Letters
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    • v.8 no.4
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    • pp.221-227
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    • 1980
  • The presence of L-malic acid in culture media contaniing glucose stimulated the growth rates of Leuconostoc oenos strains. The L-malic acid also stimulated the synthesis and activity of D-malate dehydrogenase (D-LDH) resulting in rapid production of D-lactate from glucose. The rapid utilization of glucose under the presence of L-malic acid may explain, in part, the stimulatory effect of the compound on the growth rate of leuconostocs.

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Fatigue Fracture Behavior of Laminated Steel with Mild Steel and Spring Steel (연강과 스프링압을 접합한 층상복합 강재의 피로파괴거동에 대한 연구)

  • ;;Kim, Young-Jin;Yum, Young-Ha
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.2 no.3
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    • pp.53-61
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    • 1978
  • This study has been concentrated on the relations between the crack growth rate and the stress intensity factor, the fatigue limit and finally on the condition of the crack propagation along the laminated cross section of the laminated steel under the repeated plane bending through tests. The following results are obtained. 1. The fatigue limit of the laminated steel is higher than the single steel 2. The realtion between the fatigue crack growth rate, dL/dN and Stress intensity factor are ; dL/dN = 2.14 * 10$^{-11}$ $K^{2.95}$ for SUP 9 dL/dN = 1.70 * 10$^{-11}$ $K^{2.95}$ for SMS dL/dN = 9.77 * 10$^{-11}$ $K^{2.95}$ for SPMS dL/dN = 3.57 * 10$^{-8}$ $K^{1.53}$ for SPMM dL/dN = 5.5O * 10$^{-8}$ $K^{1.53}$ for MLD 3. The crack propagation of the laminated steel also tends to be completed through 3 steps; The first step proceeds swiftly, in a second slowly for a long time and last very rapidly for a short moments.

The Factors on Somatic Embryogenesis of Soybean [Glycine max. (L.) Merrill]

  • Kim, Kyong-Ho;Kim, Hag-Sin;Oh, Young-Jin;Suh, Sug-Kee;Kim, Tae-Soo;Park, Ho-Kee;Park, Moon-Soo;Kim, Seok-Dong;Yeo, Up-Dong
    • Journal of Plant Biotechnology
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    • v.2 no.3
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    • pp.123-128
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    • 2000
  • To enhance in vitro plantlet regeneration efficiency of soybean through embryogenesis, the culture conditions such as material part and size of immature seed, 2,4-D, pH and solidifying agents for somatic embryogenesis were investigated. Somatic embryogenesis was induced from the immature embryo, immature cotyledon and embryonic axis explants of the immature seed on MS medium supplemented with 2.0 mg/L 2,4-D. The highest rate (up to 22.9%) of somatic embryogenesis was obtained from the immature cotyledon, following embryonic axis and the immature embryo. The rate varied with the developmental stages of seed. The maximum rate (25.4%) of embryogenesis was obtained from 3-4 mm length of the seed (after 25 days of flowering). The optimum concentration of 2,4-D for embryogenesis was 10 mg/L. The optimum pH was at 5.8 and solidifying agent for medium was better with 0.4% gelrite than with agar. For rapid multiplication of shoot tips from the germinating somatic embryos, they were cultured on MS medium containing 2 mg/L indole-3-butyyic acid (IBA) and 1 mg/L 6-benzyladenine (BA). After then somatic embryos with one and three cotyledons were transferred to the growth regulator free medium. The medium exhibited the higher rate (ca. 50%) of development than the multiplication medium.

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Preparation and Characterization of Poly(D,L-lactic acid) Microspheres Containing Alprazolam (Alprazolam함유 poly(D,L-lactic acid) Microsphere의 제조 및 평가)

  • Yong, Chul-Soon;Kwon, Mi-Ra;Park, Sae-Hae;Oh, Doo-Man
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.13-22
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    • 1996
  • Poly(D,L-lactic acid) (PLA) microspheres containing alprazolam(APZ) were prepared by a solvent-emulsion evaporation method and their release patterns were investigated in vitro. Various batches of microspheres with different size and drug content were obtained by changing the ratio of APZ to PLA, PLA concentration in the dispersed phase and stirring rate. Rod-like APZ crystals on microsphere surface, which were released rapidly and could act as a loading dose, were observed with increasing drug content. The release rate was increased with increase in drug contents and decrease in the molecular weight of PLA. The release rate of APZ for long-acting injectable delivery system in vitro, which would aid in predicting in vitro release profile, could be controlled by properly optimizing various factors affecting characteristics of microspheres.

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Growth Characteristics of Acidithiobacillus thiooxidans in Different Sulfur Concentrations (황 농도에 따른 Acidithiobacillus thiooxidans의 생장 특성)

  • Lee, Eun-Young;Cho, Kyung-Suk;Ryu, Hee-Wook
    • Microbiology and Biotechnology Letters
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    • v.34 no.4
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    • pp.338-341
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    • 2006
  • The growth characteristics of sulfur-oxidizing bacteria, Acidithiobacillus thiooxidans AZ11, MET, and TAS were investigated in mineral salt media supplemented with elemental sulfur of 1$\sim$50 g $L^{-1}$. The sulfur oxidation rates of A. thiooxidans. MET and TAS increased highly with increasing sulfur concentration up to 10 g L$^{-1}$, but the rates increased slowly in sulfur concentration over 10 g L$^{-1}$. A. thiooxidans AZ11 showed the parallel increase of sulfur oxidation rate until sulfur concentration increased up to 40 g L$^{-1}$. The maximum sulfur oxidation rates (V$_{max}$) of AZl1, MET and TAS were 1.88, 1.38 and 0.43 g S L$^{-1}$ d$^{-1}$, respectively. The maximum specific growth rates (${\mu}_{max}$) of AZ11, MET, and TAS were 0.33 d$^{-1}$, 0.30 d$^{-1}$ and 0.45 d$^{-1}$, respectively. Although MET and TAS couldn't grow at sulfate concentration of 40 g L$^{-1}$, AZ11 could grow in the presence of 58 g L$^{-1}$ sulfate, the final oxidation product of elemental sulfur.

Reaction Characteristics and Kinetics for Treatment of Wastewater Containing Phenol (Phenol 함유 폐수의 처리를 위한 반응 특성과 속도론)

  • Kang, Sun-Tae;Kim, Jeong-Mog
    • Journal of Korean Society of Water and Wastewater
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    • v.11 no.3
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    • pp.124-130
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    • 1997
  • Wastewater containing phenol was treated using Pseudomonas sp. B3 in continuous reactor, reaction characteristics and kinetics according to variation of volumetric loading rate in continuous reactor were studied. The removal efficiencies of phenol were more than 99% at the whole range of experiment, and those of COD were 97% at the volumetric loading rate, $0.96kg/m^3{\cdot}d$ and 88% at $3.0kg/m^3{\cdot}d$, respectively. Kinetics constants of $q_m$, $K_s$, Y and $K_d$ were obtained 0.901 l/d, 0.620mg/l, 0.659 and 0.219 l/d, respectively. As compared with to constants of standard activated sludge process, these constants were remarkably different because of toxicity and inhibition of phenol to microbes. And also, kinetics constants of oxygen utilization, a, and b, were shown 0.384 kg $O_2/kg$ phenol and 0.029 l/d.

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Oxygen Consumption of Far Eastern Catfish, Silurus asotus, on the Different Water Temperatures and Photoperiods (참메기, Silurus asotus의 수온과 광주기 변화에 따른 산소 소비량)

  • JO Jae-Yoon;KIM Youhee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.56-61
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    • 1999
  • Oxygen consumption rate of Far eastern catfish, Silurus asotus, weighing 280g, was measured using continuous flow respirometry chamber linked computer monitoring system. Mean oxygen consumption rates at $15^{\circ}C,\;20^{\circ}C,\;25^{\circ}C$, and $30^{\circ}C$ were ranged in 35.2$\~96.4mg\;O_2/kg$ fish/hr, 78.6$\~127.9mg\;O_2/kg$ fish/hr, 120.1$\~231.7mg\;O_2/kg$ fish/hr, and 197.5$\~352.3mg\;O_2/kg$ fish/hr, respectively. The oxygen consumption rates increased with increasing water temperature (p<0.05). A photoperiod-mediated oxygen consumption rates was higher during the light period than during the darkness (P<0.05). When acclimated with different photoperiods, 24L:0D, 12L:12D, and 0L:24D, the lowest oxygen consumption rate was observed in the continuous darkness (0L:24D). The differences between maximum and minimum oxygen consumption rates oyer 24 hour increased with increasing water temperature and the difference was the highest in 12L:12D. Oxygen consumption rate changed suddenly at dawn and at dusk.

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Effect of $1{\alpha},\;25\;Dihydroxyvitamin\;D_3$ on Osteoporosis in Rats ($1{\alpha},\;25\;Dihydroxyvitamin\;D_3$이 랫드 골다공증에 미치는 영향)

  • Bae, Chun-Sik;Choi, Seok-Hwa
    • Applied Microscopy
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    • v.32 no.3
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    • pp.223-230
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    • 2002
  • Vitamin D is one of important factors involved in the regulation of bone metabolism. In osteoporosis, the therapeutic effect of vitamin D on the healing process has still been controversial. To confirm the effects of $1{\alpha},\;25\;Dihydroxyvitamin\;D_3$ on the osteoporosis, the change of bone mineral density and the histologic changes of osteoporotic femur were examined comparatively in normal control group (positive control), CFA control group (negative control), CFA+$1{\alpha}$, 25 dihydroxyvitamin $D_{3}\;0.01{\mu}g/kg$ group (Vit $D_{3}L$) and CFA+$1{\alpha}$, 25 dihydroxyvitamin $D_{3}\;0.1{\mu}g/kg$ group (Vit $D_{3}H$) after osteoporosis was induced by single injection of complete Freund's adjuvant (CFA) in rats. The value of bone mineral density and bone mineral content of femur was increased in both Vit $D_{3}L$ and Vit $D_{3}H$ than CFA control, and the increase rate of that was higher in Vit $D_{3}H$ than Vit $D_{3}L$. In CFA control, the size of the bone marrow cavities significantly increased and the width from the bone marrow cavity and cortex significantly decreased than normal control. In Vit $D_{3}H$ and Vit $D_{3}L$, the increase rate of the size of bone marrow cavity and the decrease rate of the width from the bone marrow cavity and cortex was depressed than CFA control. These results suggest that $1{\alpha},\;25\;Dihydroxyvitamin\;D_3$ has therapeutic effect on adjuvant-induced osteoporosis in rats.

Effects of Photoperiod on Oviposition and Emergence of Egg Parasitoid, Trichogramma dendrolimi Mastumura (Hymenoptera, Trichogrammatidae) (광조건이 송충알벌(벌목, 알벌과)의 산란과 우화에 미치는 영향)

  • 박영규;이해풍;이기상;한만위;이정운
    • Korean journal of applied entomology
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    • v.38 no.2
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    • pp.93-99
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    • 1999
  • We investigated the effect of constant photoperiod (16L : 8D, 12L : 12D, 8L : 16D), on the oviposition, parasitism, and emergence of Trichogramma dendrolimi. Also during 16L : 8D condition circadian, oviposition and emergence of this species on artificial eggs were checked every 2hrs. When twelve eggs of Antheraea pern~i and artificial eggs were provided, the wasps had the highest rate of oviposition in the first day, and decreased dramatically there after. In these different photoperiod, the total oviposition numbers per A. pernyi eggs by the wasp were 161.8 in 16L : 8D, 145.8 in 121 : 12D and 128.5 in 8L : 16D respectively in the first day. On the other hand for the artificial egg in 16L : 8D photoperiod, the total oviposition number per egg was 106.8 in the first day, 26.6 in the 2nd day and 21.3 in the 3rd day. The rate of emergence from A. pernyi eggs was not different depend on wasp's day age, however in the artificial eggs, after the first day's 84.7% decreased considerably. The emergence rate from artificial eggs was the highest comparatively between 04:OO-0600 hours.

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