• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2909-2912
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• 2009

The amines studied in this study are less reactive toward ethyl propiolate (3) in MeCN than in H$_2$O although they are 7 to 9 pK$_a$ units more basic in the aprotic solvent. The reactivity of morpholine and deuterated morpholine toward 3 is found to be identical, indicating that proton transfer occurs after rate-determining step (RDS). The fact that kinetic isotope effect is absent excludes a stepwise mechanism in which proton transfer occurs in RDS as well as a concerted mechanism in which nucleophilic attack and proton transfer occur concertedly through a 4-membered cyclic transition state (TS). Thus, the reactions have been concluded to proceed through a stepwise mechanism in which proton transfer occurs after RDS. Brønsted-type plots are linear with small ${\beta}_{nuc}$ values, i.e., ${\beta}_{nuc}$ = 0.29 in H$_2$O and ${\beta}_{nuc}$ = 0.51 in MeCN, indicating that bond formation is not advanced significantly in RDS. The small ${\beta}_{nuc}$ value also supports the conclusion drawn from the study of kinetic isotope effect.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.165-170
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• 2014

The stems of Viburnum erosum were extracted with 80% MeOH. The concentrated extract was partitioned with EtOAc, n-BuOH, and $H_2O$. From the EtOAc and n-BuOH fractions, four compounds were isolated through the repeated $SiO_2$, octadecyl silica gel, and Sephadex LH-20 column chromatographies. Based on NMR, MS, and IR spectroscopic data, the chemical structures were determined as betulinic aldehyde (1), koaburside (2), (6R,7E,9R)-9-hydroxymegastigma-4,7-dien-3-one-9-O-${\beta}$-D-glucopyranoside (3), and byzantionoside B (4). All the compounds were isolated for the first time from the stems of Viburnum erosum.

• Korean Journal of Materials Research
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• v.16 no.4
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• pp.231-234
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• 2006

To obtain balanced white-emission and high efficiency of the organic light-emitting diodes (OLEDs), a deep blue emitter made of N,N'-diphenyl-N,N'-bis(1-naphthyl)- (1,1'-biphenyl)-4,4'-diamine (NPB) emitter and a new red emitter made of the Bis(2,4 -dimethyl-8-quinolinolato)(triphenylsilanolato)aluminum(III) (24MeSAlq) doped with red fluorescent 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H -pyran (DCJTB) were used and the device was tuned by varying the thickness of the DCJTB-doped 24MeSAlq and $Alq_3$. For the white OLED with 10 nm thickness DCJTB (0.5%) doped 24MeSAlq and 45 nm thick $Alq_3$, the maximum luminance of about 29,700 $Cd/m^2$ could be obtained at 14.8 V. Also, Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.32, 0.28) at about 100 $Cd/m^2$, which is very close to white light equi-energy point (0.33, 0.33), could be obtained.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.93-99
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• 1985

All soil characteristics for 10,077ha of establishable grassland in 1984 were statistically summarized. Soils could be classified into 5 of Order, 7 Suborder, 11 Great group, 28 Subgroup, and 105 Series by the new comprehensive classification system. Distribution rate of farm houses managed the extent magnitude of 3.0ha was 70.8% and its total extent was 35.9%. Extent rate of uncultivated method was 71.3%. These soils were distributed with regard to hilly land and mountain foot slope at, 82.0, and to 0-30% slope at 66.9%. Soil texture was light such as sandy loam to loam at 85.0%, available soil depth more than 20cm at 97.8%, and gravel content less than 35% at 98.4%. Soil would be distributed in 67.3 of first class, 29.7 second class, and 3.0% third class for suitability. Mean values of pH, available $P_2O_5$, OM, Ca, Mg and K for topsoil were 5.6, 31ppm, 3.2%, 2.23me/100gr, 1.05me/100gr, and 0.37me/100gr, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.517-522
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• 2007

The aim of this study was to compare in vitro gas production kinetics, metabolizable energy (ME), organic matter digestibility (OMD) and microbial protein (MP) production of widely used legume hays in ruminant nutrition in Turkey. Gas production were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h and their kinetics were described using the equation p = a+b ($1-e^{-ct}$). There were significant differences among legume hays in terms of chemical composition. The crude protein content of legume hays ranged from 11.7 to 18.6% of dry matter (DM); crude fat from 2.1 to 3.5% DM; neutral detergent fiber from 35.6 to 52.0% DM; acid detergent fiber from 32.0 to 35.5% DM and acid detergent lignin 1.7 to 11.0% DM. Total gas production after 96 h incubation ranged between 61.67 and 76.00 ml/0.200 g of substrate. At 24, 72 and 96 h incubation the total gas production for common vetch were significantly (p<0.01) higher than those of the other legume hays. The ME, OMD and MP of legume hays ranged from 9.09 to 11.12 MJ/kg DM, 61.30 to 75.54% and 90.35 to 138.05 g/kg DM, respectively. The ME, OMD and MP of common vetch was significantly (p<0.01) higher than those of the other hays due to low cell-wall contents and high crude protein. At the end of the experiment, differences in chemical composition of legume hays resulted in the differences in the in vitro gas production, gas production kinetics and the estimated parameters such as ME, OMD and MP. Common vetch can be recommended to hay producers and ruminant breeders, due to high ME, OMD and MP production.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.605-614
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• 2020

This study was conducted to compare the growth performances of three groups of commercial Korean native chickens (KNCs) including two strains of crossbreeds and H3 (Hanhyeop 3) from hatch to twelve weeks of age. (1A, 2A, and H3). A total of 468 one-day-old chicks were allocated in a completely randomized design with 15 replicates per treatment for the crossbreeds and 9 replicates per treatment for H3 (12 birds per cage). Commercial broiler diets (i.e., Week 0 - 5 crude protein [CP] 22.0%, metabolizable energy [ME] 3,025 kcal·kg^-1; week 5 - 8 CP 20.0%, ME 3,100 kcal·kg^-1; week 8 - 12 CP 19.0%, ME 3,150 kcal·kg^-1) were provided according to the Korean Feeding Standard for Poultry on an ad-libitum basis with fresh clean water during the twelve-week period. Body weight gain and shank length (SL) were measured weekly until week 6 and bi-weekly during week 6 to 12. Compared to H3, the two crossbreed groups had a higher body weight (BW) on weeks 3 to 8; however, the bodyweight of H3 on week 10 was significantly higher than the other groups (p < 0.05). Moreover, the average daily feed intake (ADFI) of H3 was higher than that of the two crossbreed groups from hatching to 84 days except for week 3, and H3 showed a lower average daily gain (ADG) on weeks 3 and 10 (p < 0.05). Furthermore, H3 had a higher feed conversion ratio compared to another crossbreed chicken on weeks 1 to 8 and the last week after hatching. Among all the groups, there was no significant difference for shank length during the experimental period.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.86-94
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• 2006

This study was to analyze vegetation and soil characteristic, and ordination of Bupleurum euphorbioides community located in Mt. Seorak area, Mt. Sobaek area, and Mt. South Deogyu area. Bupleurum euphorbioides community was classified into Carex lanceolata subcommunity and Chrysanthemum zawadskii var. alpinum subcommunity, and Chrysanthemum zawadskii var. alpinum subcommunity was classified into Calamagrostis arundinacea and Carex breviculmis group. In the study sites, soil organic matter, nitrogen, available phosphorous, changeable potassium, changeable calcium, changeable magnesium concentration, cation exchange capacity, and soil pH were ranged from 9.0~15.2%, 0.32~0.47%, 3.0~8.6ppm, 0.3~0.9me/100g, 0.5~1.5me/100g, 0.2~0.6me/100g, 11.4~16.1me/100g, and 4.3~4.6, respectively. And, soil texture was sandy loam or loam. The Carex breviculmis group of Chrysanthemum zawadskii var. alpinum subcommunity was found in area of high elevation and had high exchangeable K, Ca, and Mg concentration. The Calamagrostis arundinacea group of Chrysanthemum zawadskii var.alpinum subcommunity was found in area of low elevation and had lower exchangeable K, Ca, and Mg concentration than in the other subcommunity. The Carex lanceolata subcommunity was found in area of medium elevation and had medium exchangeable K, Ca, and Mg concentration. The Carex lanceolata subcommunity was located in a path of top the mountain peak, and has been destroyed. We need any action to protect the subcommunity.

• Journal of the Korean Society of Radiology
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• v.11 no.2
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• pp.157-165
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• 2017

The active transport characteristics of $K^+$ and $Na^+$ pumping system of cell membrane model which irradiated by high energy x-ray(linac 6MeV) was investigated. The cell membrane model used in this experiment was a $Na^+$ type sulfonated copolymerized membrane of styrene and divinylbenezene. The initial flux of the ion was increased with increase of both $H^+$ ion concentration. In this experiment range(pH 1.5-5, temperature $36.5^{\circ}C$), the initial flux of $K^+$ which was not irradiated by radiation was found to be from $2.09{\times}10^{-4}$ to $1.32{\times}10^{-3}mole/cm^2{\cdot}h$ and that of $Na^+$ from $7.09{\times}10^{-4}$ to $1.09{\times}10^{-3}mole/cm^2{\cdot}h$. the initial flux of $K^+$ which was irradiated by radiation was found to be from $21.0{\times}10^{-4}$ to $16.7{\times}10^{-3}mole/cm^2{\cdot}h$ and that of $Na^+$ from $62.0{\times}10^{-4}$ to $20.6{\times}10^{-3}mole/cm^2{\cdot}h$. The ratio $K^+$/$Na^+$ of membrane was about 1.10. And the driving force of pH of irradiated membrane was significantly increased about 9-20 times than membrane which was not irradiated. As active transport of $K^+$ and $Na^+$ of cell membrane model were abnormal, cell damages were appeared at cell.

• Asian Journal of Turfgrass Science
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• v.8 no.1
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• pp.25-28
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• 1994

Chemical characteristics of soils were investigated in three golf courses of Kwanak, Gold and Korea Country Club with different open year. The soil samples were collected in tee, fairway and rough. There were ranges of 4.80~5.55 in pH, 3.68~5.39% inorganic matter, 0.10~0.25% in total nitrogen, 5.63~45.64ppm in available phosphorus, 0.80~1.7lme /l00g in exchangeable Ca, 0.09~0 42me /l00g in exchangeable Mg, 0.03~0.O9me /l00g in exchangeable Na, and 0.06~0.l4me /l00g in exchangeable K. The pH was significant with golf club(P<0.05) and positively correlated with exchangeable Ca and exchangeable Mg(P<0.0l).

• Journal of Embryo Transfer
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• v.32 no.1
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• pp.9-15
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• 2017

The present study was aimed to determine the effect of green tea extract (GTE) and beta-mercaptoethanol (${\beta}$-ME) supplementation in boar sperm freezing extender on sperm motility, viability and reactive oxygen species (ROS) level. Experimental groups were allocated into Lactose-egg yolk (LEY) without antioxidant (control), GTE (1,000 mg/L GTE in LEY) and ${\beta}$-ME ($50{\mu}M$ ${\beta}$-ME in LEY). Spermatozoa extended with LEY were cooled to $5^{\circ}C$ for 3 h and then kept at $5^{\circ}C$ for 30 min following dilution with LEY containing 9% glycerol and 1.5% Equex STM (final sperm concentration: $1{\times}10^8/mL$). Spermatozoa were loaded into straws and frozen in nitrogen vapor for 20 min. Following thawing at $37^{\circ}C$ for 25 sec, sperm viability and ROS level were measured using fluorescent double stain Fertility(R) and cytometry, respectively. Motility and viability of GTE supplemented-group were higher than those of control and ${\beta}$-ME without significance. ROS level in GTE group showed significantly lower than control (P < 0.05). In conclusion, GTE supplementation in boar sperm freezing extender can reduce ROS generation during freezing.