• Title/Summary/Keyword: R40

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Studies on the Relation between Acid Deposition and Soil Chemical Properties in Forest Areas - Especially in Gyeongsangnam-Do Province - (산성강하물과 산림토양 화학성의 관련성에 관한 연구 - 경상남도 지역을 중심으로 -)

  • Lee, Chong-Kyu
    • Korean Journal of Environment and Ecology
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    • v.22 no.3
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    • pp.260-267
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    • 2008
  • This study was carried out to investigated the relation between air depositions and soil properties in Gyeongsanman province. Soil pH was average 4.40 in regions, and was the highest soil pH value in Miryang-sanne(pH 5.02), the lowest pH value in Namhae-seomyeon(pH4.08). Soil pH, soil organic matter content, avail phosphorus, K, Ca and cation exchange capacity(CEC) were significantly different among regions(p<0.05). Pb in Heavy metal content was 3.86mg/kg average value, and was the highest in Keo-je region(9.87mg/kg), the lowest in Mryang-sanne (0.86mg/kg). Zn, Cd, Cr and Ni were significantly different among regions(p<0.05). Correlation between rainfall pH and soil properties were positive in soil $pH(r=0.7826^{**})$, Ca$(r=0.6278^*)$, Mg$(r=0.5841^*)$, CEC$(r=0.6341^{**})$ and Cd$(r=0.5995^*)$, and were negative in Pb$(r=-0.5283^*)$. Correlation between $SO_2$ concentration and soil properties was negative in soil pH$(r=-0.6796^{**})$, Ca$(r=-0.5810^*)$, Mg$(r=-0.5522^*)$) and CEC$(r=-0.5905^*)$. Correlation between $NO_2$ concentration and soil properties were positive in organic matter $(r=0.6208^*)$, K$(r=0.5380^*)$. It was predicted that rainfall and $SO_2$ concentration would affect soil acidification, and soil heavy metal content related Cd and Pb. Others soil heavy metal were not related.

Condensation Heat Transfer Characteristics and Pressure Drop of R-290, R-600a, and R-22 in Horizontal Smooth Pipes with a Small Diameter (수평평활 세관 내에서의 R-290, R-600a, R-22의 응축열전달과 압력강하 특성)

  • Roh, Geon-Sang;Son, Chang-Hyo
    • Clean Technology
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    • v.14 no.1
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    • pp.53-60
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    • 2008
  • The condensation heat transfer coefficients and pressure drops of hydrocarbon refrigerants (R-290 and R-600a) and hydrochlorofluorocarbon (HCFC) refrigerants were measured in the two horizontal double pipe heat exchangers with inner diameters of 10.07 mm and 5.80 mm at a mass flux of $35.5{\sim}210.4\;kg/m^2s$ and the condensation temperature of $40^{\circ}C$. The average condensation heat transfer coefficients of hydrocarbon refrigerants were higher than that of HCFC refrigerant(R-22). The pressure drop had a magnitude in the order of R-600a > R-290 > R-22. The pressure drops in the tubes with inner diameter of 10.07 mm were approximately $6{\sim}15%$, $9.8{\sim}12.5%$ and $2.1{\sim}4.6%$ higher for R-600a, R-290 and R-22, respectively, than those with inner diameter of 5.80 mm. The condensation heat transfer coefficients were compared with the published experimental data, and showed the best agreement with Haraguchi et al.'s correlation.

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CD40 Co-stimulation Inhibits Sustained BCR-induced $Ca^{2+}$ Signaling in Response to Long-term Antigenic Stimulation of Immature B Cells

  • Nguyen, Yen Hoang;Lee, Ki-Young;Kim, Tae-Jin;Kim, Sung-Joon;Kang, Tong-Mook
    • The Korean Journal of Physiology and Pharmacology
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    • v.15 no.3
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    • pp.179-187
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    • 2011
  • Regulation of B cell receptor (BCR)-induced $Ca^{2+}$ signaling by CD40 co-stimulation was compared in long-term BCR-stimulated immature (WEHI-231) and mature (Bal-17) B cells. In response to long-term pre-stimulation of immature WEHI-231 cells to ${\alpha}$-IgM antibody (0.5~48 hr), the initial transient decrease in BCR-induced $[Ca^{2+}]_i$ was followed by spontaneous recovery to control level within 24 hr. The recovery of $Ca^{2+}$ signaling in WEHI-231 cells was not due to restoration of internalized receptor but instead to an increase in the levels of $PLC{\gamma}2$ and $IP_3R-3$. CD40 co-stimulation of WEHI-231 cells prevented BCR-induced cell cycle arrest and apoptosis, and it strongly inhibited the recovery of BCR-induced $Ca^{2+}$ signaling. CD40 co-stimulation also enhanced BCR internalization and reduced expression of $PLC{\gamma}2$ and $IP_3R-3$. Pre-treatment of WEHI-231 cells with the antioxidant N-acetyl-L-cysteine (NAC) strongly inhibited CD40-mediated prevention of the recovery of $Ca^{2+}$ signaling. In contrast to immature WEHI-231 cells, identical long-term ${\alpha}$-IgM pre-stimulation of mature Bal-17 cells abolished the increase in BCR-induced $[Ca^{2+}]_i$, regardless of CD40 co-stimulation. These results suggest that CD40-mediated signaling prevents antigen-induced cell cycle arrest and apoptosis of immature B cells through inhibition of sustained BCR-induced $Ca^{2+}$ signaling.

Effects of Gibberellin Treatment on the Berry Thinning Labor-save and Fruit Quality of 'Campbell Early' Grapevine (포도 '캠벨얼리'의 지베렐린 처리에 의한 적립 노력 절감 및 과실 품질)

  • Moon, Byung-Woo;Moon, Young-Ji;Lee, Young-Cheul;Nam, Ki-Woong
    • Journal of Practical Agriculture & Fisheries Research
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    • v.17 no.1
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    • pp.133-144
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    • 2015
  • A study was conducted to examine treatment method, proper concentration, and treatment time of gibberellin(GA3) for human labor saving at harvest in 'Campbell Early' grapevine. Fruit berry thinning reduced labor by GA3 40ppm treatment of 5 days prior to full bloom, and, at GA3 10, 20, and 40ppm during full bloom, by 14.27~19.15 minutes/tree. Therefore, although labor was reduced by dipping treatment at 40ppm of 5 days prior to full bloom and 20 and 40 ppm during full bloom, severe shattering was observed at 40ppm dipping treatment, and soluble solids decreased, which suggests difficulty with commercialization. The result suggests that proper time and concentration of GA3 fruit cluster dipping treatment at full bloom and 10 and 20ppm, respectively.

A Study on the P.T.C.R-N.T.C.R. Ceramic Resister (P.T.C.R.-N.T.C.R. 자기를 이용한 저항체에 관한 연구)

  • 안영필;이병하;김일기
    • Journal of the Korean Ceramic Society
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    • v.18 no.2
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    • pp.119-125
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    • 1981
  • The thermostable resistor was made by using P.T.C.R-N.T.C.R. ceramics. In this study $BaTiO_3$ type P.T.C.R. ceramics and $SnO_2-Sb_2O_3$ type N.T.C.R. ceramics were cocrystallized in one body and electrical resistance was stable under the temperature variation between $25^{\circ}C$-40$0^{\circ}C$. The ceramics showed the most stable electrical resistance for the mal variation when the composition was 0.6P.T.C.R. $BaTiO_3$,$ 0.4SnO_2$ and 0.01 $Sb_2O_3$.

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Growth and Yield Responses of Soybean to Overhead Flooding Duration at Four Growth Stages (관수시간에 따른 콩의 생육 및 수량반응)

  • 박경열;이종형;조영철
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.1
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    • pp.92-97
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    • 1995
  • The objective of this study is to investigate the growth characters of overhead flooded soybean plants at four growth stage. Overhead flooding treatments were applied at the vegetative growth stage ($V_3,\;V_6$) and the reproductive stage ($R_2,\;R_4$) for 6.12.24 hrs, respectively. Yield and yield components were more decreased as the overhead flooding duration was longer and the growth stage was later. Yield was not reduced significantly in soybean plants flooded at $V_3$ stage regardless of flooding duration, and flooded 6 or 12 hrs at $V_6$ stage. When compared to the control, 27 to 36% of yield reduction was observed in soybean plants flooded for 24 hrs at $V_6$ stage, 6 or 12 hrs at $R_2$ stage, and 6 hrs at $R_4$ stage. And 43%, 53% and 66% of yield were reduced through the flooding treatment for 24 hrs at $R_2$ stage 12 hrs and 24 hrs at $R_4$ stage, respectively. So yield reduction was higher in overhead flooded soybean plants at the reproductive stage than that at the vegetative growth stage.

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Evaluation of Age-dependent Crow′s Feet in Korean Women (한국여성의 연령별 눈가 주름의 정량 분석)

  • 이미영;김은정;이희경;서영경;이민선;고재숙
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.1
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    • pp.85-91
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    • 2004
  • In this study, we evaluated the crow's feet of 152 Korean women by using visual assessment established by our research group and mechanical assessment, Skin Visiometer SV 600. The volunteers were divided into 3 groups according to age; the group I of 30's was 43, the group II of 40's was 75, the group III of 50's was 34. The wrinkle score by visual assessment showed tendency to increase according to age and was statistically significant different among those three age groups (P 〈 0.05). But there was no significant difference between the left and the right of crow's feet. The 5 wrinkle parameters (RI, R2, R3, R4, R5) of mechanical assessment varied as age and the Rl, R4, and R5 showed statistically significant difference among three age groups (P 〈 0.05). However there was no significant difference between the left and the right of crow's feet. The volunteers were divided into 3 groups according to wrinkle score; (0-3 grade for group A, 4-6 grade for group B, 7-9 grade for group C). Only R4 and R5 showed significant difference between group A and group C (P 〈 0.05). It was suggested that visual scoring criteria applied in this study was related to R4 and R5 and was useful in investigating in fine wrinkles.