• Polymer(Korea)
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• v.29 no.3
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• pp.288-293
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• 2005

Osmotic granule system which is one of the drug delivery systems has been developed to improve manufacturing process and other problems of tablet osmotic systems. It consists of water swellable seed layer, nifedipine drug layer, and drug release controlled membrane layer and manufactured by fluidized bed coater. The granule size and mombrane thickness can be controlled by various amounts of seed and coating solution, respectively. It could be observed that the morphology of osmotic granule was different at each coating step as well as type of coating solution. The bigger the size of granule, the slower the release rate was observed due to decreasing the total specific surface wed of granule. Also, it was observed that the increase of membrane thickness was caused to retard the dissolution of nifedipine due to decreasing the water absorption rate. The drug solubility for dissolution media is greatly affected to nifedipine release. From these results, we assured that osmotic granule can be fabricated by fluidized bed coating methods, and the appropriate release profile could be controlled by the controlling of bead size, membrane thickness and dissolution media.

• Resources Recycling
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• v.23 no.6
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• pp.22-29
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• 2014

Recycling process of iron should be developed for efficient recovery of neodymium (Nd), rare metal, from acid-leaching solution of Nd magnet. In this study, $FeCl_3$ solution as iron source was used for preparation of iron nano particles with the condition of various factors, such as, reductant, and surfactant. $Na_4P_2O_7$ and Polyvinylpyrrolidone (PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride ($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed by using XRD, SEM for measuring shape and size. Iron nano particles were prepared at the ratio of 1:5 (Fe (III) : $NaBH_4$). Size and shape of iron particles were round-form and 50 ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4P_2O_7$ was negative value, which was good for dispersion of metal particle. When $Na_4P_2O_7$ (100 mg/L), PVP($FeCl_3:PVP$ = 1 : 4, w/w) and Pd($FeCl_3:PdCl_2$ = 1 : 0.001, w/w) were used, iron nano particles which were round-shape, well-dispersed and near 100 nm-sized range. In this condition, $FeCl_3$ solution changed with spent Nd leachate solution, and then it is possible to be made round-formed iron nano particles at pH 9 and at the reaction bath over 20 L which is not include any surfactant.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.617-622
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• 2011

The study was conducted to determine the efficiency in producing spontaneous polyploids in some mandarin hybrids with different seed embryony. Seed formation by open pollination, frequency of spontaneous polyploids, and plant growth characteristics were evaluated in four mandarin hybrids with polyembryony such as 'Amakusa', 'Haruka', 'Hayaka', and 'Seminole' and two with monoembryony such as 'Benibae' and 'Harehime'. The mean number of the developed seeds per fruit was 10.0 and frequency of small seeds was 25.1%. Polyploids were selected from plants germinated in vitro by a flow cytometry and confirmed by chromosome analysis. One triploid was produced from 'Harehime', one tetraploid, 'Amakusa', and one tetrapoid, 'Benibae'. There were little differences in leaf shape, thickness, petiole length, and internode length between diploids and polyploids such as tri- or tetraploid. However, polyploids had larger stomata and lower density of stomata in abaxial epidermis than diploids. SPAS indicating chlorophyll content and photosynthetic rate were significantly affected by ploidy level. The results indicated that spontaneous polyploids might be produced by open pollination in some mandarin hybrids and monoembryony had higher frequency in polyploid occurrence than polyembryony.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6187-6195
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• 2012

Recycling process of iron should be developed for efficient recovery of neodymium(Nd), rare metal, from acid-leaching solution of neodymium magnet. In this study, $FeCl_3$ solution as iron source was used for synthesis of iron nanoparticle with the condition of various factors, etc, reductant, surfactant. $Na_4O_7P_2$ and polyvinylpyrrolidone(PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed with instruments of XRD, SEM and PSA for measuring shape and size. Iron nanoparticles were made at the ratio of 1 : 5(Fe (III) : $NaBH_4$) after 30 min of reduction time. Size and shape of iron particles synthesized were round-form and 50 nm ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4O_7P_2$ was negative value, which is good for dispersion of metal particle. When $Na_4O_7P_2$(100 mg/L), PVP($FeCl_3$ : PVP = 1 : 4, w/w) and Pd($FeCl_3$ : $PdCl_2$ = 1 : 0.001, w/w) were used, iron nanoparticles which are round-shape, well-dispersed, near 100 nm-sized can be made.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.483-488
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• 2011

Cacalia firma recently has been used increasingly as leaf vegetables but endangered in natural forest. In this work, we established the plant regeneration via adventitious shoot formation from petiole segments of seedling and in vitro plantlets. Wounding of seed coats and $GA_3$ treatments were effective to induce in vitro germination of seeds, whereas, seed did not germinate at all without these treatment. When cotyledon, leaf, petiole, and root segments of seedling were cultured on medium with 2 $mg{\cdot}L^{-1}$ benzyl adenine (BA) and 0.5 $mg{\cdot}L^{-1}$ naphthaleneacetic acid (NAA), petiole segments showed highest number of shoots per explant among the other segments. Among the various kinds of cytokinins, BA, isopentyl adenine (2-ip), kinetin, zeatin, thidiazuron (TDZ), TDZ and BA treatments were effective to induce high frequency of adventitious shoot formation from petiole segments of in vitro propagated plants. NAA stimulated the frequency of adventitious shoot formation but not for number of adventitious shoots per explants compared to TDZ or BA treatment alone. Most of adventitious shoots were developed directly from surfaces of explants. Adventitious shoots were transferred on medium with IBA for root formation, thereafter the plantlets were successfully transferred to soil.

• Korean Journal of Medicinal Crop Science
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• v.15 no.5
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• pp.339-345
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• 2007

Field performance and morphological characterization was conducted on seven transgenic lines of Codonopsis lanceolata expressing ${\gamma}-TMT$ gene. The shoots were obtained from leaf explants after co-cultivation with Agrobacterium tume-faciens strain LBA 4404 harboring a binary vector pYBI 121 that carried genes encoding ${\gamma}-Tocopherol$ methyltransferase gene (${\gamma}-TMT$) and a neomycin phosphotransferase II gene (npt II) for kanamycin resistance. The transgenic plants were transferred to a green house for acclimation. Integration of T-DNA into the $T_0\;and\;T_1$ generation of transgenic Codonopsis lanceolata genome was confirmed by the polymerase chain reaction and southern blot analysis. The progenies of transgenic plants showed phenotypic differences within the different lines and with relative to control plants. When grown in field, the transgenic plants in general exhibited increased fertility, significant improvement in the shoot weight, root weight, shoot height and rachis length with relation to the control plants. However, all seven independently derived transgenic lines produced normal flower with respect to its shape, size, color and seeds number at its maturity. Indicating that the addition of a selectable marker gene in the plant genome does not effect on seed germination and agronomic performance of transgenic Codonopsis lanceolata. $T_1$ progenies of these plants were obtained and evaluated together with control plant in a field experiment. Overall, the agronomic performance of $T_1$ progenies of transgenic Codonopsis lanceolata showed superior to that of the seed derived non-transgenic plant. In this study, we report on the morphological variation and agronomic performance of transgenic Codonopsis lanceolata developed by Agrobacterium transformation.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.239-244
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• 2015

Calanthe striata f. sieboldii Decne. ex Regel is a terrestrial orchid with beautiful flowers arranged in racemose inflorescences. This species is threatened due to over-collection and loss of suitable habitats. Asymbiotic germination is useful in the conservation efforts to re-establish plants in the wild, and for commercial propagation. In this study, we investigate the effects of sodium hypochlorite (NaOCl), three types of culture media (Phytomax Orchid Maintenance - POM, Seed Germination Maintenance - SGM, and Murashige and Skoog 1962 - MS), and plant growth regulators on embryo swelling, protocorm formation, and embryo diameter of C. striata f. sieboldii. Treatment with 1% NaOCl for 30 min greatly enhanced embryo swelling (28.3%), embryo diameter ($205.8{\mu}m$), and embryo protocorm formation (54.8%) compared to seeds without NaOCl treatment (embryo swelling 8.5%, embryo diameter $14.6{\mu}m$, and protocorm formation 13.4%) on POM medium. Protocorm formation on POM medium supplemented with 1.0 mg/L N6-benzyladenine (BA) (95.6%) was better than the control (54.5%). Additionally, the effects of activated charcoal (AC) and sucrose on seedling growth in in vitro culture were examined. The protocorm converted into healthy plants with well-developed shoot primordia on the POM medium with AC and sucrose. The most suitable conditions for seedling growth after 10 weeks of culture were the POM medium with AC or sucrose. These results show effective asymbiotic seed germination and in vitro seedling growth of C. striata f. sieboldii.

• Journal of Korean Society of Forest Science
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• v.96 no.6
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• pp.652-660
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• 2007

The study was intended to investigate the changes of construction types of 216 non-national forest roads, which were completed between 1989 and 2005 in Jeollabuk-do, by analyzing their drawing and specification. It was found that the mean length of yearly construction has been significantly reduced after the Policy of Green Forest Roads compared with before the policy. Soil cut-off of earth work was changed from bulldozer to a combination of bulldozer and excavator. Soils were transported by truck in all design, but establishment of spoil-bank was not designed at all. The design of slope revegetation works was developed from turfing and Bastard indigo planting to seed spray, combination of seed spray and belt-sodding, and mulching with coir net and rice straw. In design of the culvert, the average interval of culvert installation was reduced to 92m in step 3, the dimension of culverts was expanded to over 600 mm after step 2, and all drainpipes were corrugated steel pipes. The design length of concrete pavement increased from 40 m/km of step 1 to 240 m/km of step 3. Thanks to the enormously increased amount of concrete pavement, the stability and functionality of forest roads could be improved. Stone masonry was the main work drawn for slope stability, and concrete retaining wall and gabion have been drawn for same object since 1999.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.7-12
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• 2009

Mungbean should be harvested several times according to its physiological characteristics and weather conditions of cultivation region. In Korea, mungbean is usually sown in June and harvested three or four times, and the cultivated area is being rapidly reduced. Therefore, the author developed cultivation techniques of mechanical harvesting suitable for the weather conditions of the southern part of the Korean peninsula. The optimum sowing time of mungbean for mechanical harvesting in southern part of Korea is around July 20. When sown around July 15, mungbean should be harvested twice and then the mechanical harvesting of mungbean was not possible. Meanwhile, when sown after July 25, the mechanical harvesting was possible but the maturing period was longer and the seed yield was decreased. Therefore, it is safe to say that in Korea the mechanical harvesting of mungbean is possible for the middle part of Korea when the plant is sown before July 20 and for the southern coastal region of Korea when sown after July 20 (if July 20 is set up as the baseline for the southern part of Korea). Out of Keumseong and Owool, which are popularized cultivars in Korea most, Owool is determined to be most appropriate for mechanical harvesting. Owool is favorable for mechanical harvesting because, when compared to Keumseong, it is higher both in plant height and in pod height, and also the seed yield is better.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.179-186
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• 2015

This study was conducted to understand the characteristics of flowering and the factors affecting fruiting grades of Acer pictum subsp. mono(APSM), We examined the characteristics of flowering and fruiting in various natural APSM forest, and investigated annual fruiting grade, DBH, tree height, number of APSM trees within 30 m on 29 selected trees in the natural broadleaved forest in Mt. Jungwang in Gangwon-do, from 2009 to 2014. APSM has heterodichogamous sexual system consist of protoandry and protogyny. Eight trees have changed their sex morphs; 3 trees change the sex morph PA to PG, and 5 trees does the sex morph PG to PA. Early fall of young ovary is concentrated until early July. Initially, the small samaras are common, and was gradually increased the samaras suffered insect damage. Most flowers of APSM are pollinated by Andrenidae sp., Syrphidae sp. and Tachinidae sp.. Number of early fall samaras and the status of fallen samaras showed a significant difference by the year and region. Corymbose panicle and young leaves developed on the top of APSM twigs. Newly grown opposite twigs of APSM did not grow sufficiently and had no floral buds. The highest fruiting grade of tree was 9.0, and the mean values was only 3.8. The highest fruiting grade of year was 4.55 in 2013, and the lowest did 0.07 in 2014. Highly significantly correlated and regressed between mean of annual fruiting rates and rates of crown under sun light. This results would imply that thinning for tree growth through improved light absorption might be a method to enhance seed production of APSM in the seed production forest.