• Journal of the Korean Wood Science and Technology
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• v.30 no.1
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• pp.11-17
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• 2002

This study was performed to determine the characteristics of particleboard made from three-months-old bamboo, (Phyllostachys nigra var henonis Stapf) grown in Damyang district, Korea. Total 60 particleboards were manufactured with 1% of liquid wax emulsion using urea-formaldehyde resin content 9%,11% and 13%, respectively. The particle boards consisted of three layers, in which face layer had the same proportion of a weight 25% of the particleboard each. And the core layer had a weight 50% of the board. The core layer and face layer had the particle dimension passing 6 mesh (3.35 mm), 12 mesh (1.70 mm), respectively. The study was carried out to determine the effect of the growing time of 3 months and 3 years on particleboard properties. The physical and mechanical properties of boards were measured and compared to the Korean standard (KS) requirements of particle boards. The results were as follows; 1. The longer the growing time, the higher the density of bamboo. Density of the upper part of bamboo showed higher than that of lower part. 2. Density and moisture content of the two particle boards did not show significant differences. Three-months-old bamboo particleboard gave higher thickness swelling than three-years-old bamboo particleboard. Bamboo particleboard passed the thickness swelling test of KS. 3. The static bending and internal bond strength of three-months-old bamboo particleboard were higher than those of three-years-old bamboo. Increase of resin contents in bamboo particleboard increased bending and internal bond strength, proportionally. Strength properties of bamboo particle board were above KS. 4. Formaldehyde emission of all the bamboo particleboards satisfied E₂ level (5.0 mg/L) of KS F 3104.

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.151-156
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• 2000

Field experiments were conducted to investigate the yield and paeoniflorin content between healthy peony and blight plot of top part with every year during 3 years at June, July, August, September, separately. Stem length and diameter, No. of stem in the blight plot of peony were decreased in early in blight time compared with those in no blight growth. No. of flower buds per plant was 5.2, 4.6 in 3 year- grown and 4year-grown plots at late June blight compared with 11.5, 16.2 in no blight. No. of axillary flower was also similar to as above. Main root length and root diameter was most decreased in the plot of late June blight compared with healthy peony. No. of root more than 10mm of root diameter was small in order of blight time, namely Late June, July, August and September. The root dry yield of 4 year healthy peony was most high in 1,603kg per 10a, but it was lowed in 1,007kg in the plot lasted blight during 3years at late June. Paeoniflorin content was no different between 3year-grown and 4year-grown, but it was high in late June blight plot increased with the early in blight time.

• Life and Agrochemicals
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• s.268
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• pp.46-47
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• 2011

1~2년생 초화류에는 꽃양귀비, 꽃도라지, 금어초, 스타티스, 스토크, 팬지, 페튜니아, 일일초, 아프리카봉선화 등이 대표적인 작물이다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.4 no.2
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• pp.7-14
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• 1983

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.437-441
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• 2004

These studies were conducted to investigate the proper method of nitrogen application for increasing the growth stability and quality in ballon flower (Platycodon grandiflorum A. DC.). In growth characteristics by split ratio of nitrogen application, stem diameter, number of branching roots and number of leaves were higher at the split ratio of 50:50 (nitrogen were splitted a half with basal application and the other half in autumn) than at 70:30. Root length, root diameter and number of branching root were higher at 50:50 than those of 70:30. The root yield was increased by 30% (230 kg/10a) at 50:50 compared with that of the 70:30. The crude saponin contents of root from 50:50 was 4.68%.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.67-74
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• 2023

The river pufferfish (Takifugu obscurus) is a valuable species in aquaculture and genetic studies. Usage of fish anesthetics aids in the easier handling of fish during aquaculture. However, there are no studies on appropriate conditions required for effective anesthetization of pufferfish. This study aims to determine the optimal conditions (fish age, water temperature, anesthetic concentration) needed for the most common fish anesthesia, MS-222, to anesthetize T. obscurus. We tested three different water temperatures (20℃, 24℃, and 28℃), three different anesthetic concentrations (125 mg/L, 150 mg/L, and 175 mg/L), and two different fish ages (one- and two-year-old). Appropriate anesthetization conditions for T. obscurus ranged from 150 mg/L to 175 mg/L of MS-222 at 24℃ to 28℃ for one-year-old fish. For two-year-old fish, the appropriate conditions ranged from 150 mg/L to 175 mg/L of MS-222 at 28℃. However, to minimize side effects and risks, 150 mg/L of MS-222 at 24℃ for one-year-old fish and 175 mg/L of MS-222 at 28℃ for two-year-old fish are recommended for effective anesthetization.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.266-272
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• 2018

A Polygonatum stenophyllum Maxim. is an important endangered plant belonging to the family Liliaceae. A method was developed for the rapid micropropagation of P. stenophyllum through plant regeneration from rhizome (1-year, 3-years, and 5-years) explant-derived calli. The rhizome segments were cultured in Murashige and Skoog (MS) medium supplemented with varying concentrations of 2,4-D (0, 0.5, 1.0, $1.5mg{\cdot}L^{-1}$) for callus induction. In media supplemented with $0.5mg{\cdot}L^{-1}$ of 2,4-D, 87% of 3-years rhizome produced callus. Subsequently, the callus was transferred to 1/2MS medium supplemented with various concentrations of IAA, IBA, NAA, and 2,4-D (0, 0.1, 0.5 and $1.0mg{\cdot}L^{-1}$) for adventitious shoot formation. The highest percentage of adventitious shoot induction (57%) was observed in 1/2MS medium containing $0.5mg{\cdot}L^{-1}$ of NAA. Elongation of the adventitious shoot was achieved in 1/2MS medium supplemented with $0.1mg{\cdot}L^{-1}$ of BA. Rooting was achieved in 1/2MS medium without any hormones. It is hypothesized that the stated in vitro propagation protocol will be useful for conservation and mass propagation of the endangered Polygonatum stenophyllum Maxim. for bioresources.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.485-489
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• 2000

The patterns and contents of ginsenosides were examined in normal root parts and hairy root lines of Panax ginseng C. A. Meyer. Ginsenoside-Rb$_1$, -Rb$_2$, -Rc, -Rd, -Re, -Rf, -Rg$_1$, -Rg$_2$ were detected in normal roots and hairy roots of ginseng. The patterns and contents of ginsenosides in that were very difference each other. The contents of total ginsenoside of hairy root (KGHR-1) was 17.42 mg/g dry wt, it's highest compared to others. Ginsenoside contents of hairy root (KGHR-1) was higher on ginsenoside-Rd, Rg$_1$, KGHR-5 was higher on ginsenoside-Rb$_1$, Rg$_1$, and KGHR-8 was higher on ginsenoside-Rd, Re than others. The contents of total ginsenosides on 6 years old ginseng cultured in the field were high in the order of main root, lateral root and fine roots, and content of ginsenosides in fine roots was 3.2 times higher than that in main root. The ratio of ginsenoside-Rg$_1$to total ginsenosides were about 3.43%, 8.68% and 14.18% respectively on fine root, lateral root and main root, it's very lower than that in hairy roots. It is suggested that specific ginsenosides can be produce in cultures of ginseng hairy roots.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.299-305
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• 2007

Ecological characteristics of Koreocobitis rotundicaudata was investigated in the mid-upper part of the Naerin stream in Hongcheon gun, Gangwon do, Korea from April 2006 to March 2007. It inhabited mostly on the cobble and pebble bottoms with water-current velocities of 0.3~0.8 m/sec and depths of 30~80 cm. The sex ratio of female to male was 1 : 0.78. It was presumed that the spawning season was from May to June with water temperatures $20.1{\sim}23.1^{\circ}C$. Sexually matured individuals appeared over the two years of age. Body length frequencies indicated that the 40~69 mm group is over one year old, the 70~109 mm over two years old, and 110~142 mm over three years old. The average number of eggs in the ovaries was 1,365. Main prey materials were Ephemeroptera and Chironomidae mostly.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.19-25
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• 2015

The purpose of this study is to reveal the effect of plant life cycle to plant settlement by 1 year monitoring. The subjects of monitoring are the plants (3 plant life cycle, 9 taxa) well established in the mesocosm. 18 mesocosms were divided into 3 sets and water levels were maintained at 0, 20 and 60 cm during 16 weeks from mid-May, respectively and at 0 cm except these 16 weeks. Height and population size of transplanted perennial plants (Scirpus tabernaemontani, Zizania caduciflora, Typha (Typha angustifolia and Typha orientalis)) at 1st year were not affected by diverse water level, though any more seedlings of these species were not settled at this condition. In contrast, water level condition strong influenced annual and biennial plant, relatively. As a result, timing and duration of flooding have great effect on successful settlement of annual and biennial plant without rhizome.