• Title/Summary/Keyword: Mg reduction

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Geomicrobiological Behavior of Heavy Metals in Paddy Soil Near Abandoned Au-Ag Mine Supplied with Carbon Sources (탄소원을 공급한 폐금은광산 주변 논토양 내 중금속의 지구미생물학적 거동 연구)

  • Ko, M.S.;Lee, J.U.;Park, H.S.;Shin, J.S.;Bang, K.M.;Chon, H.T.;Lee, J.S.;Kim, J.Y.
    • Economic and Environmental Geology
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    • v.42 no.5
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    • pp.413-426
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    • 2009
  • The study was conducted to investigate the effects of indigenous bacteria on geochemical behavior of toxic heavy metals in contaminated paddy soil near an abandoned mine. The effects of sulfate amendment to stimulate microbial sulfate reduction on heavy metal behaviors were also investigated. Batch-type experiments were performed with lactate or glucose as a carbon source to activate indigenous bacteria in the soil under anaerobic condition for 100 days. Sulfate (250 mg/L) was artificially injected at 60 days after the onset of the experiments. In the case of glucose supply, solution pH increased from 4.8 to 7.6 while pH was maintained at 7~8 in the lactate solution. The initial low pH in the case of glucose supply likely resulted in the enhanced extraction of Fe and most heavy metals at the initial experimental period. Lactate supply exerted no significant difference on the amounts of dissolved Zn, Pb, Ni and Cu between microbial and abiotic control slurries; however, lower Zn, Pb and Ni and higher Cu concentrations were observed in the microbial slurries than in the controls when glucose supplied. Sulfate amendment led to dramatic decrease in dissolved Cr and maintenance of dissolved As, both of which had gradually increased over time till the sulfate injection. Black precipitates formed in solution after sulfate amendment, and violarite($Fe^{+2}{Ni^{+3}}_2S_4$) was found with XRD analysis in the microbial precipitates. Conceivably the mineral might be formed after Fe(III) reduction and microbial sulfate reduction with coprecipitation of heavy metal. The results suggested that heavy metals which can be readily extracted from contaminated paddy soils may be stabilized in soil formation by microbial sulfate reduction.

Effect of Flubendazole against Ascayis Zumbyicoides, yyichocephalus tyichiuyus and Enteyobius vermicularis in Bnfeeted Children (Flubendazole의 회충, 편충 및 요충에 대한 구충효과)

  • Min, Deuk-Yeong;An, Myeong-Hui;Kim, Gyeong-Min
    • Parasites, Hosts and Diseases
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    • v.24 no.1
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    • pp.12-14
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    • 1986
  • Effectiveness of aubendazole, a newly introduced as an anthelmintic in Korea, was evaluated in 28 ascariasis, 28 whipworm in(tractions and 17 Pinworm infections in Primary school children. All Patients were orally given by aubendazole of 500mg once. Stools for roundworm and whipworm and anal swabs for pinworm infections were examined both before and 25 days after treatment. After flubendazole treatment, all ascariasis and pinworm infected cases were cured. On the other hand, in whipworm infections, the cure rate was 82.1% (23 cured of 28 infected), and the egg reduction rate was 67.1%, respectively, Headache (one case), dizziness (2 cases) and abdominal pain (3 cases) were noticed as untoward effects, but they were mild and disappeared within 24 hours. These results demonstrate the excellent efEectiveness of aubendazole in treating these helminth infections.

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Proton Effect on the Degradation of Phenolic Compound by Activated Sludge and Nocardia asteroides (활성슬러지 혼합미생물과 Nocardia asteroides에 의한 페놀화합물 분해시 양성자이온의 영향)

  • 조관형;조영태;우달식
    • Journal of Environmental Science International
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    • v.11 no.6
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    • pp.561-567
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    • 2002
  • This study was investigated to evaluate the effect of the sodium ion and pH on toxicity of dinitrophenol at high concentrations (0.41 to 0.54 mM), over a sodium concentration range of 0.1 mM to 107 mM and over a pH range of 5 to 9. The concentration of sodium ions in the activated sludge mixed liquor seemed to have very little effect on dinitrophenol toxicity. However, lack of sodium in the growth media resulted in a reduction of the dinitrophenol degradation rate by bacterial isolate from the activated sludge culture, which has been identified as Nocardia asteroides. Dinitrophenol inhibition was found to be strongly dependent on mixed liquor pH. The dinitrophenol degradation rate was highest in the pH range of 6.95 to 7.84; at pH 5.94 degradation of 75 mg/L dinitrophenol was significantly inhibited; at pH < 5.77, dinitrophenol degradation was completely inhibited after approximately 30% of the dinitrophenol was degraded.

A Study on the Determination of Carbon monoxide in the Blood by Spectrophotometry (분광광도법에 의한 혈중일산화탄소의 측정에 관한 연구)

  • 정근호
    • Journal of Environmental Health Sciences
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    • v.2 no.1
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    • pp.49-51
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    • 1975
  • The accidents, homicides and suicides of carbon monoxide poisoning to increase in number every year are required precize, accurate, and rapid method for the determination of carbon monoxide in the blood samples. Here is the basis of this method for the determination of percentage saturation of hemoglobin by carbon monoxide which have found out to be suitable in laboratory as follows: A 0.1ml of blood is mixed with 20ml of 0.1% ammonium hydroxide, and 20mg sodium hydrosulfite is added to convert oxyhemoglobin to reduction hemoglobin. The absorbance is measured at 538nm and 578nm, the measurement was carried out within ten minutes of addition of sodium hydrosulfate.

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Reduction of Estradiol Receptor in Rat Atretic Follicle Induced by Dihydrotestoterone Enanthate (DHTE) (DHTE로 유발된 흰쥐 폐쇄난포의 에스트라디올 수용체의 감소)

  • 유용달;이창주;이준영
    • Journal of Embryo Transfer
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    • v.5 no.2
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    • pp.28-37
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    • 1990
  • Dihydrotestoterone (DHT)은 난소내 폐쇄를 유발한다고 보고 되었으나, 반대로 폐쇄를 억제한다는 상반된 주장이 있어왔다. 본 연구는 난소내 폐쇄되는 기작을 밝히는 연구의 일환으로 흰쥐의 DHT를 처리하여 난포가 폐쇄되는지 여부와 폐쇄된다면 스테로이드 수용체, 특히 에스트라디올 수용체에 어떠한 영향을 주는지를 조사하고자 하였다. 미성숙 흰쥐의 뇌하수체를 절제(HPX)하고, 35IU의 PMSG 처리후 Dihydrotestoterone enathate (DHTE)를 lmg-5mg/kg 체중 농도로 처리하여 난포의 폐쇄여부를 조직학적으로 검경하였다. PMSG,PMSG-DHTE 공히 강소를 형성한 난포의 acid phosphatase 활성도를 증가시켰고, 또한 난포의 폐쇄를 유발하였다. 흰쥐의 난소내 estrogen receptor (ER)의 수는 과립세포에서도 세포질내 ER은 핵내로 이용되는 것을 확인하였다. 또한 DHTE는 난소내 ER의 농도를 감소시켰다. 이 결과로 보아 난포내 DHTE는 ER의 농도를 감소시켜 폐쇄를 유발하는 요인으로 작용할 것이라는 결론을 얻었다.

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Factors Influencing the Removal of Nutrient by Seawater (해수에 의한 영양염 제거에 있어서 영향인자의 평가)

  • Cortes, Aiza;Kim, Woo-Hang
    • Proceedings of KOSOMES biannual meeting
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    • 2009.06a
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    • pp.145-147
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    • 2009
  • Nutrients in wastewater should be removed prior to release in the receiving waters to prevent the occurrence of eutrophication. In this study, seawater is used to remove ammonia and phosphate by the formation of struvite ($MgNH_{4}PO_{4}{\cdot}6H_{2}O$). It aims to know the optimum conditions for the removal of nutrients using seawater as source of magnesium ions. Experiments were performed using jar tester and pH of ammonium-phosphate solutions were adjusted Samples were drawn at different mixing times. It was shown that simultaneous removal of ammonia and phosphate is rapid, with no significant reduction beyond 10 min of mixing Another important parameter is pH, where range 10-11 showed the optimum nutrient removal. Increase in the volume of seawater, which meant an increase in magnesium ions also lead to better removal.

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Pharmacetical Characteristics and Analysis of Garlic Extract (마늘 추출물의 약리적 특성 및 분석)

  • Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.24 no.3
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    • pp.301-308
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    • 2007
  • From the experiment result on pharmacetical characteristics and analysis of Garlic extract, some conclusions were obtained as follows. From the results on extract experiment of Garlic, extraction ratio was about 6.0%, and after dried with dry oven from Garlic extract, it obtained about 50%-Garlic extract of solid state. From results on antimicrobial experiment of Garlic extract, number of staphylococcus and fungus in microbe decreased more and more according to time passage. This phenomenon showed that Garlic extract keeps antimicrobial effect. From results on antioxidation experiment of Garlic extract, DPPH scavenging activity of free radical showed that Garlic extract appears more remarkable reduction ability than reference samples. This phenomenon means that antioxidation of Garlic extract appears higher than Vitamin-C and BHA. From results on instrument analysis, inorganic components of K, Na, Ca, Si, Mg, Zn etcs from Garlic extract were detected with ICP/OES and the fatty and aromatic components of trimethyl sulfide, diallyl disulfide, diallyl trisulfide, 2-mercaptobenzothiazole etcs from Garlic extract were detected with GC/MS.

Serpentine Pretreatment Using Electrolyzed Reduced Water for Mineral Carbonation Materials (전해환원수를 이용한 탄산염 광물화 원료용 사문석의 전처리)

  • Choi, Weon-Kyung
    • Journal of Hydrogen and New Energy
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    • v.20 no.5
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    • pp.447-454
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    • 2009
  • Electrolyzed reduced water was known as an alkaline solvent than piped water, natural water and mineral water etc. By means of reduction property, electrolyzed reduced water could dissolve a solute than other kinds of water without chemicals. In this study, serpentine dissolution in electrolyzed reduced water was investigated as a novel pre-treatment of serpentine which was a minerals for carbon dioxide sequestration. The elements (Ca, Si, Mg etc.) of serpentine were dissolved rapidly at early in the dissolvation then after some minutes the solubilities of serpentine elements showed stable state without abrupt changes. In spite of serpentine elements dissolution, chemical bondings and crystallographic structure of serpentine were not changed. It was explained that the dissolution mechanism of serpentine occurred from surface in electrolyzed reduced water and bulk structure sustained without collapse.

Role of Sodium lon in Biodegradation of Nitroaromatic Compound by Activated Sludge and Pure Cultures

  • Jo, Kwan-Hyung
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.3
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    • pp.169-175
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    • 1999
  • 2,4-Dinitrophenol(DNP) is a metabolic uncoupler that prevents cells from creating energy for growth and it has been suggested that the availability of sodium ions may be important in mitigating the effects of uncouplers. Accordingly, the degradation of DNP was investigated using activated sludge which had been adapted to mineralize DNP. After the acclimation of the activated sludge, the effect of sodium ions on the toxicity of high concentrations(80 to 100mg/L) of DNP was investigated over a sodium ion concentration range of 9.3$\times$10-5 to 94mM. The concentration of sodium ions in the activated sludge mixed liquor seemed to have little effect on the DNP toxicity. However, a lack of sodium in the grwoth media resulted in a reduction of the DNP degradation rate by a bacterial isolate from the activated sludge culture identified as Nocardia asteroides.

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Alteration of Physical Properties of Nanoparticle Embedded liquid Crystal Causing the Enhancement of the Performance of LCDs

  • Kobayashi, Shunsuke;Kineri, Tohru;Takatoh, Kohki;Akimoto, Mitsuhiro;Hoshi, Hajime;Nishida, Naoto;Toshima, Naoki;Sano, Satoru
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1473-1476
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    • 2008
  • Doping the nanoparticles of Pd, p-$BaTiO_3$, $SiO_2$ and MgO into LCs alters their physical properties such as $K_{ii}$, $\Delta\varepsilon$, ${\Delta}n$, $\gamma_1$ and $T_{NI}$. Except for $K_{33}$, all these parameters decreases and thus bring the reduction of operating voltage and/or response times.

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