• Title/Summary/Keyword: discolor

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Effect of ICCP Potential with Electrolyte on Corrosion and Discolor of Silver (은의 부식 및 변식에 미치는 전해질 용액에 따른 ICCP 전압의 영향)

  • Shin, Byung-Hyun;Kim, Do-Hyung;Chung, Won-Sub
    • Journal of the Korean institute of surface engineering
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    • v.53 no.5
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    • pp.207-212
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    • 2020
  • Silver is an inexpensive precious metal and is used in various jewelry in Asia. Although silver has high potential, it has corrosion resistance that is vulnerable to boiling sulfuric acid and nitric acid. So, silver research is needed to prevent the corrosion with environment. But silver corrosion is not studied. sulfuric acid make the uniform corrosion and chloride ion make the pitting corrosion. ICCP inhibits the corrosion because it offset electrons. This study used a potential from - 4 V to 4 V to check the effect of potential. Corrosion rate is lowet at -1 V.

Optimization Conditions for Cryopreservation of Potentilla discolor Bunge (솜양지꽃(Potentilla discolor Bunge)의 초저온동결보존을 위한 최적 조건 탐색)

  • Yang, Woo Hyeong;Yong, Seong Hyeon;Park, Dongjin;Seol, Yuwon;Choi, Eunji;Jeong, Mi Jin;Choi, Myung Suk
    • Journal of Korean Society of Forest Science
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    • v.107 no.3
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    • pp.258-265
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    • 2018
  • This study was conducted to investigate the effective cryopreservation condition of Potentilla discolor Bunge, a rare native plant. Seed viability was more than 80% in PVS2 and PVS3 solution treatments. Seed viability was higher in PVS3 than PVS2 treatment. Seed viability was lower than control in spite of sucrose pretreatment. The germination rate was 95% at 60 min of PVS2 treatment and 30 min of PVS3 treatment but the germination rate was low at other treatments. The growth of the seedling wasn't doing that of the control except for treat PVS2 and PVS3 solution for 30 min. There was no statistically significant difference between the encapsulation method and the vitrification method in the seedling growth between the two cryogenic storage methods. This study is expected to be applied to future conservation methods of Potentilla discolor.

Soil Acclimatization of Calanthe discolor through Multiple Shoot Formation from Tissue Culture (새우난초(Calanthe discolor)의 조직배양으로부터 다신초형성을 통한 토양순화)

  • Bae, Kee-Hwa;Yoon, Eui-Soo;Yun, Pil-Yong;Choi, Yong-Eui
    • Korean Journal of Plant Resources
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    • v.23 no.1
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    • pp.7-13
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    • 2010
  • This experiment was conducted to establish the micropropagation of Calanthe discolor through multiple shoot formation from the culture of leaf, corm and root explants. Frequency of adventitious shoot formation from leaf explants was higher than those of corms and root explants. Frequency of adventitious shoot formation on medium with various concentrations of BA (0. 1.0, 3.0, and 5.0 mg/L) and NAA (0, 0.1, 0.5, and 1.0 mg/L) was tested. The maximun induction of adventitious shoot was obtained on half strength Murashige and Skoog (MS) medium supplemented with 3.0 mg/L BA and 1.0 mg/L NAA after 6 weeks of culture. Multiple shoots were transferred onto half strength MS medium with various concentrations of GA3 (0, 0.1, 0.5, 1.0, 3.0, and 5.0 mg/L). The number and length of multiple shoots on medium were highest on medium with 3.0 mg/L GA3. All the adventitious shoot grew well and rooted on half strength MS medium with 3.0 mg/L NAA. The plantlets were acclimatized up to 100% on sand with TKS-II or pearlite with TKS-II.

Asymbiotic Germination of Korean Native Calanthe Species (한국(韓國) 자생(自生) 새우난초 종자(種子)의 무균발아(無菌發芽))

  • Kim, Chang-Kil;Chung, Jae-Dong
    • Current Research on Agriculture and Life Sciences
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    • v.15
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    • pp.47-52
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    • 1997
  • The experiment was carried out to find the optimal condition for seed germination in vitro of Calanthe species. Seeds of Calanthe spp. after 90 days self pollination were well germinated in the MS medium. Germination condition of cross seeds between C. discolor and C. striata was much improved by pretreatment of micro sonic waves for 10 min. The days of germination was more shortened. and protocorm growth was more promoted in microsonic wave treatment than in non-treatment.

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Electrophoretic Karyotyping by PFGE in the Genus Fusarium (Fusarium속에서 PFGE를 이용한 Electrophoretic Karyotyping)

  • Min, Byung-Re;Jung, Jin-Sook;Choi, Yong-Keel
    • The Korean Journal of Mycology
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    • v.26 no.2 s.85
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    • pp.135-143
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    • 1998
  • Contour-clamped homogeneous electric field gel electrophoresis was used to establish electrophoretic karyotype for 10 species of Fusarium sections Sporotrichiella, Liseola, Gibbosum, Discolor and Martiella. Intact chromosomal DNA was isolated from fungal protoplast and separated under various conditions according to their size in order to improve DNA separation. The numbers of chromosome-sized DNA molecules for individual species ranged from 5-13, with individual chromosomes ranging from 0.78 Mb to 7.20 Mb in size. The total genome DNA size of each species was estimated at about 18.32 Mb to 48.20 Mb. Comparison of karyotype profiles following Southern hybridization analysis with a randomly selected genomic probe of F. oxysporum formae speciales litii was carried out.

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Effect of concentration of H2SO4 on electrochemical properties of equipped Al sacrificial anode to prevent the corrosion and discolor of silver surface (은의 표면 부식 및 변색을 방지하기 위해 설치된 Al 희생양극의 전기화학적 특성에 미치는 황산 농도의 영향)

  • Shin, Byung-Hyun;Chung, Won-Sub
    • Journal of the Korean institute of surface engineering
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    • v.54 no.1
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    • pp.12-17
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    • 2021
  • Among the various precious metals, silver is used in various fields because of its low price than other precious metals. However, the surface of silver remains after rain in the atmosphere containing sulfur ions and chlorine ions, causing silver corrosion and discoloration. Existing documents have developed a anode to prevent corrosion but that are concentrated on secondary batteries. This study tried to prevent corrosion and discoloration of silver by using an Al sacrificial anode. Sulfuric acid decreased the potential of silver and increased the current density at active polarization and OCP. The amount of corrosion of silver with the Al sacrificial anode was reduced from 0.5 % to 6.5%. When silver is used for decoration outside, corrosion and discoloration of silver can be suppressed by installing an Al anode.

Micropropagation of Calanthe discolor Lindl. through Induction of Multiple Shoots from Axillary Bud Culture (새우난초(Calanthe discolor Lindl.)의 액아배양으로부터 다신초 형성을 통한 대량증식)

  • Lim, Ju Hong;Chung, Mi Young;Kim, Chang Kil;Lim, Ki Byung;Chung, Jae Dong
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.4
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    • pp.239-246
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    • 2008
  • This study was conducted to establishment of in vitro micropropagation through induction of multiple shoots from axillary bud culture in Calanthe discolor Lindl. Shoots initiation from axillary bud was the most effective on half strength MS medium supplemented with $0.5mg{\cdot}L^{-1}$ NAA and $2.0mg{\cdot}L^{-1}$ TDZ during four weeks of dark culture followed by culture under a 16-h photoperiod. Multiple shoots (12.5 shoots per explant) were proliferated on half strength MS medium containing $4.0mg{\cdot}L^{-1}$ TDZ and $2.0mg{\cdot}L^{-1}$ IBA. On the other hands, the abnormally emerged shoots during the multiple shoot proliferation stage were recovered to normal shoots on half strength MS hormone free medium. Multiple shoots were well elongated and rooted on half strength MS medium with $0.1mg{\cdot}L^{-1}$ NAA. The plantlets were acclimatized up to 100% on TKS substrate after pretreating with $10mg{\cdot}L^{-1}$ NAA for 30 min. and these plantlets showed good growth as well.

Taxonomic revision of the Artemisia sacrorum group (더위지기 및 근연분류군의 분류학적 재검토)

  • Park, Myung Soon;Nam, Bo Mi;Chung, Gyu Young
    • Korean Journal of Plant Taxonomy
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    • v.46 no.2
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    • pp.175-186
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    • 2016
  • The taxonomic status and scientific names of Artemisia gmelinii and its allied taxa have long been debated. To provide correct names and taxonomic status, A. gmelinii and its allied taxa were reviewed in this study based on morphological characters. After a comparison of original descriptions and type specimens, the names of A. freyniana f. discolor and A. freyniana f. vestita used in Korea were recognized as A. sacrorum var. sacrorum and A. sacrorum var. incana, respectively, based on the characters of the trichome on the leaf, the geographical distributions, the chromosome numbers, and the existence of a pinule connection on the exine of the pollen. A. iwayomogi, the scientific name misused as A. gmelinii, was combined and newly named A. sacrorum var. iwayomogi (Kitam.) M. S. Park & G. Y. Chung based on its morphological similarity to the A. sacrorum group. A description, illustration, and key for each of the taxa are provided here.

Nomenclature of Calanthe discolor, C. sieboldii and C. bicolor Native to Cheju Island for Horticultural Use (제주(濟州) 자생(自生) 새우란, 금새우란, 왕새우란의 원예품종화)

  • Hyun, Myung-Ryuk;Choi, Ji-Yong;Suh, Jung-Nam;So, In-Sup;Lee, Jong-Suk
    • Horticultural Science & Technology
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    • v.17 no.3
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    • pp.346-351
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    • 1999
  • According to their flower color and the shape of petal, sepal, and lip, Calanthe species native to Cheju Island are named as follows; 'Arang', 'Cheongsu', 'Sara', 'Aeyeol', 'Darigot', 'Saebaengi', 'Andeok', 'Setbyeol', 'Kyorae', 'Jasujeong', 'Baekrok', 'Seokwang', 'Deokcheon', 'Seonheul', 'Saechimi', 'Jokduri', 'Baedal', 'Noksu', 'Noeul', and 'Dansim for 20 cultivars of Calanthe discolor; 'Hwanghee', 'Waheul', 'Illchool', 'Hwangryong', 'Dabo', 'Hwangjinee', 'Daeha', 'Chwikwang', 'Seokyang', 'Eunpa', 'Chwiseon', 'Sinbaram', 'Ara', 'Dano', 'Pakae', and 'Sojeob' for 16 cultivars of Calanthe sieboldii; 'Dongkwang', 'Myeongdeok', 'Wangdolseon', 'Myeongryeok', 'Kwibuin', 'Semi', 'Cheonwangsa', 'Mandeok', 'Seolmundae', 'Kyeongok', 'Darangsi', 'Byeolbang', 'Honghak', 'Dongbaeksan', 'Chejudo', 'Samda', 'Kwandeok', 'Youngjusan', 'Tamra', 'Koyeongdi', 'Yongduam', and 'Jeolbuam' for 22 cultivars of Calanthe bicolor.

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