• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.2
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• pp.19-28
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• 2009

Echinosophora koreensis (Nakai) Nakai (Leguminosae) is one of the threatened plant growing in secondary forest with sparse pine forest. The aim of this research is to investigate current status in a habitat of E. koreensis population, and obtain knowledge for conservation of the population. The flora of vascular plants and vegetation were investigated in the habitat E. koreensis in Mt. Bibong, Gangweon Province. Investigation were carried out in August 2003 and May 2008 at the three different habitats. As a result, a total 40 species 7 varieties of 28 family were recorded in whole area. The vegetation of investigated area was typical northern-temperate Pinus forest, humidity of soil was low and located at a slope area. These investigated area is very important for conservation of rare plant, E. koreensis. Therefore, sustainable conservation strategy such as designation of conservation area should be prepared urgently by the results of long-term monitoring studies.

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.31-39
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• 2015

The synergistic solvent extraction of rare earth elements such as europium and yttrium has been investigated by the extractant with crown ether as an additive. Macrocyclic ligand as host-guest compounds form more stable complexes with metal ions which have the similar size of the cavity of crown ether. In our previous study[14] founded that the extraction used fatty acid of the various alkyl chain length. Based on the results of the previous experiment, the synergistic separation effect of two metals investigated that the hexanoic acid had was the worst extraction effect which added a crown ether such as 18-crown-6 ether, 15-crown-5 ether, and 12-crown-4 ether. In this study, the concentrations of hexanoic acid have showed the separation effect, and then the concentrations and kind of crown ether are performed for synergistic extraction at the hexanoic acid concentration of the highest separation effect. As a results, the separation rate is the highest value of 1.72 at 0.05 M hexanoic acid, and 0.002M 15-crown-5 ether is the best value in other concentrations and kind of crown ether, it is about twice of using only hexanoic acid. Moreover, the extraction species of two metals has been founded $MLR_3{\cdot}3RH$ form when added the crown ether.

• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.393-397
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• 2006

Thuja koraiensis Nak. is a short and creeping evergreen shrub which reaches about 3 m in height and only occurs in the northeast China and in high mountains over the Korea. It's designated as a rare and endangered tree species in Korea and DD (data deficient) in Red List Category & Criteria of IUCN. This study was carried out to develop the propagation technique by cutting for conservation of genetic resources of T. koraiensis. The rooting responses of branch cuttings, obtained from hard (May) and semi-hard wood shots (August) to three plant growth regulators (PGRs), namely, IAA, IBA, and NAA applied at various concentrations (0, 100, 500, 1000, 2000, and 3000 mg/l) were examined in sand and mixed soil media. Percentage of rooting showed significant difference between cutting time, among kinds and among concentration of PGRs. The optimum cutting time was April to May in hardwood cutting. The application of IAA 1000 mg/l and NAA 500mg/l were effective in callus formation and rooting of cutting. Relatively, rooting of cutting of the control taken in May was above 93%.

• Korean Journal of Environmental Biology
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• v.28 no.3
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• pp.158-171
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• 2010

The flora of Deokjeok Island was investigated 35 times from September 2007 to September 2008. Based on voucher specimens, the study indicated that this area consisted of 535 taxa in total; 108 families, 320 genera, 480 species, 2 subspecies, 45 varieties and 8 forms were present. Compositae and Graminae were the first and second most common families surveyed in the region, respectively. Among the more remarkable examples found were four taxa of Korean endemic plants, six taxa of rare and endangered plants designated by National Arboretum, and 55 taxa of specific plants that have been designated by the Ministry of Environment. Furthermore, 50 taxa of naturalized plants were observed and they occupied 17.9% of the total in the surveyed area. Although some parts of the investigated region were disturbed by human impact, the ecological status was comparatively well preserved. However, the area where the remarkable plants were discovered should be more systematically protected. Since the proportion of naturalized plants in the human habitation area was considerably high and the spreading of these plants seems consistent, it is expected that the ecosystem of this area may become critically unstable in near future.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.509-513
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• 2010

Recently, an amount of waste electronic devices such as LED and trichromatic fluorescent lamp has increased with the development of electronic industry. Reportedly, rare earth metals such as yttrium and europium have been discovered in the waste electronic devices. In order to improve the selectivity of yttrium and europium, the effects of the following factors on recovery experiment have been considered : i) fatty acids with various alkyl chain lengths, ii) the concentration of extractant, and iii) pH. The results show that the extraction efficiencies decrease at the same pH with decreasing the concentration of extractant and so $pH_{0.5}$ (That value of pH in an aqueous phase at which the distribution ratio is unity at equilibrium: 50% of the solute is extracted (E = 0.5) only when the phase ratio is unity.) moves into higher pH. The highest selectivity of yttrium and europium was obtained with tetradecanoic acid as extractant. The extraction mechanism of yttrium and europium was varied with the change of concentration of the tetradecanoic acid. $MR_3$single-species was formed from the yttrium and europium ion in the extractant concentration less than 0.1 M. On the other hand, the yttrium or europium ion is solvated with three molecules of tetradecanoic acid monomer like $MR_3{\cdot}$ 3RH in the extractant concentration more than 0.1 M.

• Korean Journal of Plant Resources
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• v.23 no.4
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• pp.327-349
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• 2010

This study was carried out to investigate the distribution of vascular plants and their use from 2007 to 2009 in Mt. Unmum(Cheongdo-gun, Gyeongsangbuk-Do). The vascular plants were summarized as 605 taxa including 98 families, 304 genus, 514 species, 3 subspecies, 68 varieties, and 20 forma. Among the investigated 605 taxa, 21 rare and endangered plants, 29 Korean endemic plants were included. Based on the list of specially designated plants by Ministry of Environment, 70 taxa included Iris odaesanensis and Gastrodia elata were recorded in the investigated area. The naturalized plants were identified as 23 taxa and the percent of naturalized index(NI) was 3.8% of total 605 taxa vascular plants. Usage of 605 taxa were consists of 225 taxa(37.2%) of edible plants, 191 taxa(31.6%) of medicinal plants, 64 taxa(10.6%) of ornamental plants, 46 taxa(7.6%) of pasture plants, 18 taxa(3.0%) of timber plants, 14 taxa(2.3%) of fiber plants, and 3 taxa(0.5%) of industrial plants. To management of natural resource, we suppose that it is required to establish an ecological learning area to minimize human disturbance and an effective managemet strategy by continuous monitoring for ecosystem change.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.566-588
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• 2013

This study was carried out to investigate the vascular plants of the Mt. Gariwang (1,560.6 m) Protected Area for Forest Genetic Resource Conservation. The vascular plants collected 5 times (from May 2011 to October 2012) consisted of total 529 taxa; 89 families, 272 genera, 458 species, 3 subspecies, 62 varieties and 6 forms respectively. Among them, 22 taxa of Korean endemic plants and 30 taxa of Korean rare plants were investigated in addition to 144 taxa of specially designated plants announced by the Ministry of Environment of Korea. Naturalized plants were 15 taxa, therefore naturalized ratio was 2.83%. 529 taxa listed consists of 178 taxa (33.6%) of edible plants, 144 taxa (27.2%) of medicinal plants, 163 taxa (30.8%)of pasture plants, 68 taxa (12.8%) of ornamental plants, 20 taxa (3.8%) of timber plants, 8 taxa (1.5%) of fiber plants, respectively.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.1-21
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• 2009

The vascular flora of Dalmasan and its adjacent regions, located in Haenam-gun, Jellanam-do, is surveyed from Mar. to Oct. 2005. The number of the vascular plant taxa based on voucher specimens is 545 total which belongs to 112 families, 322 genera, 473 species, 3 subspecies, 60 varieties and 9 forms respectively. Among them, 12 taxa of Korean endemics and 4 taxa of rare and endangered plants were investigated in addition to 86 taxa of specially designated plants announced by the Ministry of Environment. A unrecorded taxon, Stellaria neglecta Weihe, is also collected in this area. Furthermore, The habitat of 5 taxa such as Asplenium trichomanes L., Asplenium wilfordii Mett. ex Kuhn, Miscanthus sinensis var. chejuensis Y.N.Lee, Impatiens kojeensisi Y.N.Lee and Digitaria violascens var. intersita Ohwi were newly added to the flora of korea, and 29 taxa of induced and naturalized plants were observed in this area.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.209-224
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• 2012

This study was carried out to survey the vascular plants of Namhan River located in Chungju-si, and the period of survey was from June, 2010 to June, 2011. The results are as follows. The vascular plants distributed in Neungam, Mokgye and Jangcheon around Namhan river were summarized as 225 taxa including 52 families, 164 genera, 200 species, 23 varieties and 2 forms. The rare plant designated by Korea Forest Service was $Aristolochia$ $contorta$ Bunge, and the endemic plant was identified as $Salix$ $koriyanagi$ Kimura. The specific plants by floristic region were 7 taxa including $Salix$ $chaenomeloides$ Kimura, $Aristolochia$ $contorta$ Bunge, $Actinostemma$ $lobatum$ Maxim., $Artemisia$ $selengensis$ Turcz., $Cirsium$ $pendulum$ Fisch., $Alisma$ $plantago-aquatic$ var. $orientale$ Samuels. and $Carex$ $versicaria$ L.. The naturalized plants were 47 taxa including $Fallopia$ $dumetorum$ (L.) Holub., $Chenopoidum$ $album$ L., $Silene$ $armeria$ L., $Brassica$ $juncea$ (L.) Czern., $Melilotus$ $alba$ Medicus, $Trifolium$ $pratense$ L., $Oenothera$ $erythrosepala$ Borb$\acute{a}$s, $Ipomoea$ $hederacea$ var. $integriuscula$ A.Gray, $Bidens$ $frondosa$ L., $Matricaria$ $inodora$ L., $Xanthium$ $canadense$ Mill., $Panicum$ $dichotomiflorum$ Michx. and so forth. In life forms, megaphanerophytes (M) were 13 taxa, 13 taxa in nanophanerophytes (N), 14 taxa inchamaiphytes (Ch), 40 taxa in hemicryptophytes (H), 20 taxa in geophytes (G), 103 taxa in therophytes (Th) and 22 taxa in hydrophytes (HH). The ratios of the naturalized index (NI), the urbanized index (UI) and the disturbed index (DI) were 20.9%, 14.6% and 18.2% in all sites.

• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.123-132
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• 2001

The regional distributions and relative frequencies of some gastrointestinal endocrine cells in the 8 portions (fundus, pylorus, duodenum, jejunum, ileum, cecum, colon and rectum) of the gastrointestinal tract of ICR mouse (ICR) with immunohistochemical method using 7 types of specific antisera against somatostatin, serotonin, glucagon, cholecystokinin (CCK)-8, secretin, pancreatic polypeptide (PP) and gastrin. In this study, somatostatin-, serotonin-, glucagon-, CCK-8-, secretin- and gastrin-immunoreactive (IR) cells were identified. Most of these IR cells in the intestinal portion were generally spherical or spindle in shape (open-typed cell) while cells showing round in shape (close-typed cell) were found in the stomach regions occasionally. Their relative frequencies were varied according to each portion of gastrointestinal tract. Somatostatin-IR cells were demonstrated throughout whole gastrointestinal tract except for large intestine. Serotonin-IR cells were detected throughout whole gastrointestinal tract and they were most predominant endocrine cell types in this species of mouse. Glucagon-IR cells were restricted to the fundus and rectum with moderate and a few frequencies, respectively. CCK-8-IR cells were observed in the pylorus, duodenum and ileum with numerous, moderate and rare frequencies, respectively. Secretin-IR cells were restricted to the duodenum and ileum with a few and rare frequencies, respectively. Gastrin-IR cells were restricted to the pylorus with numerous frequency. However, no PP-IR cells were found in this study. In conclusion, some peculiar distributional patterns of gastrointestinal endocrine cells were found in the ICR mouse compared to those of other mammals.