• Title/Summary/Keyword: 카드늄

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Preventive Effect of Lysis in the Cadmium-Tolerant Hansenula anomala B-7 Cells by Metal Ions (금속 이온에 의한 카드늄 내성균주 Hansenula anomala B-7 세포의 용균 방지 효과)

  • Song, Hyung-Ik;Yu, Tae-Shick
    • The Korean Journal of Mycology
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    • v.19 no.4
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    • pp.282-284
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    • 1991
  • The yeast, Hansenula anomala B-7, isolated from the $Cd^{2+}$ rich soils and determined to be tolerant in the high concentration of $Cd^{2+}$ were employed in this work. Its intact cells grown in high concentration of $Cd^{2+}$ were observed to be Iysed at the early stage when transferred to a cadmium deficient broth. Its intact cells found to be not Iysed and grow well under the high concentration of $Cd^{2+}$. The Iysis of the intact cells grown at the high concentration of $Cd^{2+}$ ion was not found when the metal ions were replaced with $Cd^{2+}$ ion in the same concentration. This result indicated that Iysis of yeast cells, at least in this isolate, would be related to cell osmosis with the mineral ions added.

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Effect of Cadmium Treatment on the Total Thiol Groups, Glutathione and Phytochelatin Contents in Oenanthe javanica (카드늄을 처리한 미나리 (Oenanthe javanica)에서 전체 Thiol 잔기, 글루타치온, Phytochelatin의 농도 변화)

  • Min, Bok-Kee;Choi, Soon-Yong;Lee, Se-Yong
    • Applied Biological Chemistry
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    • v.40 no.3
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    • pp.243-248
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    • 1997
  • In order to evaluate the usefulness of O. javanica for the phytoremediation, it was grown for 1, 3, 7, 14, 21 days and was exposed to $50\;{\mu}M\;of\;CdCl_2$ in hydroponic medium after 3 weeks. Its biomass and contents of chlorophylls were analyzed. The growth of O. javanica showed little difference between cadmium treated and non-treated groups, while its contents of chlorophylls of Cd-treated group decreased up to 50% compared to the case of non-treated group. Its accumulated cadmium concentrations were 2.1, 7.3 and $113\;{\mu}moles\;Cd/g$ dry weight in the leaf, stem and root, respectively. The total contents of thiol increased 0.5, 1 and 7 times in the leaf, stem and root, respectively, while the contents of glutathione tended to decrease by 43%, 70% and 47% in the leaf, stem and root, respectively. Using HPLC analysis, the reasonable peaks of thiol compounds in shoot and root of Cd-treated sample were compared to those of non-treated sample in O. javanica, and found to be phytochelatins. In case of Nicotiana tabacum cv. Xanthi tested as control plant, the cadmium treatment for 3 weeks resulted in the decrease of both biomass and chlorophyll up to 70% and 75%, respectively. The roots of tobacco became rotten and eventually died. These results suggested that Oenanthe javanica is cadmium-tolerant hyperaccumulator.(Received December 20, 1996; accepted March 17, 1997)

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Overview of Cadmium Exposure from Plant-based Food Consumption in Global Population especially in Asia and Techniques to Reduce the Risks to Human Health (인체 건강에 위해성을 감소시키기 위한 기술과 세계 인구. 특히 아시아에서 식품 소비에 근거한 식물체로부터의 카드늄 노출 개관에서는 전세계 카드늄)

  • Su, S.W.;Chen, Z.S.
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.spc
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    • pp.4-7
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    • 2009
  • Agricultural soils contaminated by cadmium (Cd) are common problems in Asia due to rapid industrial development, so the risks of Cd exposure from food crops consumption are concerned by public and authorities. The latest data on Cd concentration in plant-based food and the dietary intakes of Cd around the world are presented in this review. In general, Cd concentrations in major plant-based commodities seldom exceed 0.05 mg/kg fresh weight and decline in the order as: cereals > pulses > vegetables > roots and tubers > fruits in Far Eastern region. In Middle Eastern and European regions, the order is vegetables > cereals > roots and tubers > pulses > fruits. Rice has the highest Cd levels among cereals in Asian countries, but in Middle Eastern and European region the highest level of Cd occurred in leaf vegetables. The dietary intakes of Cd from plant-based commodities around the world declined in the order as: cereals > vegetables > roots and tubers > fruits > pulses. Rice is the largest contributor to total dietary Cd intake (58%) in the Far Eastern region and contributed 36% of Provisional Tolerable Daily Intake (PTDI). For high foodstuffs consumers, intake of Cd from all diets may exceed PTWI, especially for high rice consumers in Asian countries. The World Health Organization (WHO) conducted impact assessment of different maximum levels (MLs) of Cd and demonstrated that each of the four possible MLs for rice had little impact on dietary Cd intake. Since many Cd-contaminated soils in Asian countries still producing crops due to the growing population, the cost-effective techniques for reducing Cd contents in crops especially rice grain are absolutely required.

Competitve Interactions of Cadmium with Magnesium in Three Different Soil Constituents (3개의 다른 토양에서의 카드늄과 마그네시움의 경쟁적 상호작용)

  • Doug-Young Chung
    • Journal of Korea Soil Environment Society
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    • v.1 no.1
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    • pp.81-88
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    • 1996
  • To study the Cd adsorption in the presence of competing ions in soil-solution interphase, three soil samples from the Bt horizon were taken and analyzed for their physical and chemical properties. Adsorption of ethylene glycol monoethyl ether(EGME) and N, were determined to establish the specific surface area of the soils. We attempted to establish a qeneralizing competitive sorption isotherms for soils of entirely different composition of the solid phase, resulting in the routine use as a guidelines for the fate of reactive solute in soil profiles. Many physicochemical factors including competitive adsorption bettween solutes will affect the general adsorption phenomena as shown in a single not only on the soil:solution ratio used, but also on the surface areas of its respective soil samples. This phenomenon was attributed to competition Cd for sorption sites with Mg by different soil constituents. These adsorption isotherms are able to use as examples to demonstrate that this phenomenon can complicate the development of a standardized batch adsorption procedure as well as interpreting fate and adsorption of toxic inorganic compounds.

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The Case Study on Cadmium Embrittlement Failure of High Strength Bolt (고강도 볼트 카드늄 취성파괴 사례연구)

  • Yoon, Young-In
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.5
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    • pp.769-774
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    • 2010
  • It happened fractures on special bolt which supported main landing gear actuator up-lock rod of aircraft. Cracks were initiated mainly from the center hole and the external thread of the special bolt. To find out failure root causes, metallographic, fractographic analyses as well as test work were carried out. From the fractographic study by SEM work, fracture occurred by a brittle intergranular type failure. The fracture could be occurred primarily by solid-metal-induced embrittlement due to cadmium embrittler penetrated into the flaw existed after machining work for center hole and thread on the bolt during baking treatment processing to eliminate hydrogen. For its successful application, cadmium EP bolts require proper and adequate baking treatment after electroplating, and make no more drilled center hole on the bolt to prevent same failure.

Uptake of Heavy Metal Ions by Water Dropwort (Oenanthe stolonifera DC.) and Identification of Its Heavy Metal-Binding Protein (미나리의 중금속 흡수량 측정 및 중금속 결합단백질의 동정)

  • Park, Young-Il;Kim, Hee-Guen;Kim, Yoo-Young;Kim, In-Soo
    • Applied Biological Chemistry
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    • v.39 no.6
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    • pp.494-500
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    • 1996
  • Uptake of hen metal ions by water dropwort (Oenanthe stolonifera DC.) and its cadmium-binding protein were studied to probe for good method to remove heavy metal contaminants from environments. The plant was cultured in the culture medium (pH 7.0) containing the various concentrations of $Cd^{2+}$, $Cr^{3+}$ or $Pb^{2+}$, for 3 and 7 days. The residual heavy metals deposited in roots linearly increased as the metal ions concentration increased up to 17 ppm for $Cd^{2+}$, 20 ppm for $Cr^{3+}$ and 50 ppm for $Pb^{2+}$. Above these concentrations, the plant growth was inhibited and the uptake rates of the metal ions decreased. The heavy metals absorbed by the plant were mostly deposited in roots. In particular, the residual concentration of lead in roots was about four times higher than those of cadmium and chromium. When cultured in the medium containing 20 ppm of each metal ion, 80% of cadmium, 90% of cromium and 96% of lead were deposited in roots out of the total residual metal ions in the plant. These values correspond to 6.1 mg of cadmium, 5.2 mg of chromium and 23.6 mg of lead per one gram of roots tissue on a dry weight basis. A cadmium-binding protein was partially purified by extraction, gel filtration and DEAE-Cellulose chromatography from water dropworts that was grown in the medium containing 20 ppm $Cd^{2+}$. The purified protein was a single band on SDS- and non-denaturing- polyacrylamide gel electrophoresis. Its molecular mass was estimated to be ca. 5,000 dalton by gel filteration. Analysis of amino acid composition of the protein indicated that it had a typical amino acid composition of heavy metal-binding protein in that it contained 27% of acidic amino acids and 9.9% of cysteine. However, it is likely that the protein is a new plant metal-binding protein, since its amino acid composition is somewhat different from those of phytochelatins that have been known so far.

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The Case Study of High Strength Bolt Cadmium Embrittlement Failure (고강도 볼트 카드늄 취성파괴 사례연구)

  • Yoon, Young-In;Park, Chan-Wook;Sohn, Kyung-Suk
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.244-249
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    • 2008
  • It happened a failure on special bolt which supported main landing gear actuator up-lock rod of 00 aircraft. Fracture was occurred at end of center drilled hole and thread machined on bolt. Metallographic, fractographic, and other characteristics of embrittlement analysis and experiments carried out on the failed bolt to find out the reason. Bolt surface was cadmium electroplated(EP) to give lubrication and provide excellent corrosion resistance. Resultly, Bolt was failed due to cadmium embrittlement occurred during baking treatment as well as center drilled hole. for the failure that are relevant to failure analysis and prevention. For their successful functional application, cadmium EP bolts require proper and adequate baking treatment after electroplating, and is complete with no center drilled hole

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