• Title/Summary/Keyword: Sulphide

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Process Development for Effective Denitrification by Biofilter Using Loess Ball

  • CHOI DU BOK;LEE DONG BYUNG;CHA WOL SUK
    • Journal of Microbiology and Biotechnology
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    • v.15 no.2
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    • pp.412-420
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    • 2005
  • In order to investigate factors affecting the denitrification in the F-STEP PROCESS using a loess ball as support media and Pseudomonas DWC 17-8, calcining temperature, loess ball size, pH, nitrate concentration, working temperature, and inhibitor were studied in batch mode using synthetic sludge. A 5- 10 mm of loess ball (960$^{circ}$ of calcining temperature) was the most suitable for denitrification. When the initial pH was increased from 3.0 to 7.0, the removal efficiency of nitrate was increased. Specifically, at initial pH of 7.0, the maximum removal efficiency of nitrate was 5.0 mg/min. When the initial concentration of nitrate was increased from 100 to 400 mg/l, the removal efficiency of nitrate was proportional to the concentration of nitrate. The maximum removal efficiency of nitrate was 5.72 mg/min at 400 mg/l of initial concentration. When the operating temperature was increased from 10 to 30$^{circ}$, the removal efficiency of nitrate was increased from 0.76 to 6.15 mg/min, and at above 40$^{circ}$ of operating temperature, it was decreased from 4.0 to 2.0 mg/min. Among the various inhibitors, higher than 10$^{-1}$ M of sodium azide abolished this reaction completely. When the KCN concentration was above 10$^{-1}$ M, the reaction was inhibited completely. In the case of 2,4-dinitrophenol and sodium sulphide, it was inhibited at above 10$^{-2}$ M completely. For testing the various flow orders of the F-STEP PROCESS for effective denitrification using practical wastewater, continuous experiments under the optimum conditions were carried out for 60 days. Among the various processes, the PROCESS A gave the highest efficiencies of denitrification, nitrification, and total nitrogen (TN) removal with 86.5, 89.5, and $90\%$, respectively. For scale-up in the PROCESS A, real farm wastewater was used and pilot tests carried out for 90 days. The denitrification efficiency was $97.5\%$, which was increased by $12.7\%$. The efficiencies of TN removal and nitrification were 96.6 and $70.0\%$, respectively. The removal efficiency of chemical oxygen demand (COD) was $63.7\%$, which was increased by $20\%$.

Lead-Zinc-Tin-Silver Mineralization of Tangguanpu Mine, Hunan Province, China: Fluid Inclusion and Sulfur Isotope Studies (중국 호남성 당관포 광산의 연-아연-주석-은 광화작용: 유체포유물 및 황동위원소 연구)

  • 허철호;윤성택;소칠섭
    • Economic and Environmental Geology
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    • v.34 no.2
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    • pp.157-166
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    • 2001
  • Numerous base-metal bearing hydrothermal quartz vein deposits occur in the Hunan province of southern China. The Tangguanpu lead-zinc-tin-silver mine is the major producer among these deposits. Lead-zinc-tin-silver mineralization occurs in a single stage of massive quartz veins which filled fractures in fault zones within Paleozoic metasedimentary rocks. Sphalerite, chalcopyrite, galena, pyrite, arsenopyrite and pyrrhotite are the principal sulphide minerals in the Tangguanpu lead-zinc ores with minor amounts of tin- and antimony-bearing sulphides (stannite, teallite, boulangerite and tetrahedrite). Based on the iron and zinc partitioning between coexisting stannite and sphalerite, the formation temperature for this mineral assemblage range from 300$^{\circ}$ to 330$^{\circ}$C, which relatively agree with the upper part of homogenization temperature of fluid inclusion in quartz (20T-358$^{\circ}$C). Fluid inclusion data show that main lead-zine-tin-silver mineralization occurred from $H_{2}O$-NaCl fluids with relatively low salinities (11.2-7.3 wl.% eg. NaCI) at temperatures between 207$^{\circ}$ and 358$^{\circ}$C. The relationship between homogenization temperature and salinity suggests a history of cooling and dilution followed by initial boiling. Evidence of initial fluid boiling may indicate the fluid trapping pressures of 180 bars. The ${\delta}^{34}S{{\Sigma}S}$ values of -5.0 to 1.1 %, indicate an igneous source of sulfur in the Tangguanpu lead-zinc-tin-silver hydrothermal fluids.

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Alterations of Binding Capacities of Dopamine Receptors After Treatment with Haloperidol and Sulpiride in Rat Brain (Haloperidol 및 Sulpiride 투여후 백서 뇌내 Dopamine 수용체 결합력의 변화)

  • Hahn, Kyu-Hee;Ahn, Yun-Young
    • Korean Journal of Biological Psychiatry
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    • v.2 no.1
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    • pp.63-69
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    • 1995
  • The effects of chronic treatment with haloperidol and sulpiride on the binding capacities of dopamine(DA) receptor were examined in rat striatum and olfactory tubercle. Additionally, the stereotypy scores were assessed after apomorphine administration. Rats were treated with haloperidol(0.5mg/kg/day) or sulpiride(40mg/kg/day) for four weeks. Apomorphine(0.5mg/kg) was injected after three-day washout from neuroleptics, and stereotypy scores were assessed. Haloperidol group showed high scores of stereotyped behavior in comparison with control and sulpiride groups. With control group, sulpiride group displayed similar stereotyped behaviors. Saturation analysis of the binding of [$^3H$]spiperone to striatal membranes showed that the Bmax of haloperidol and sulpiride groups increased significantly in comparison with that of control group. The $K_D$ decreased significantly after sulpiride treatment in striatum. Although sulpiride produces the same proliferation of DA receptor, the low stereotypy scores of sulpiride group indirectly suggest that sulpiride acts differently from haloperidol in brain DA system. The Bmax increased remarkably following both treatment with haloperidol and sulpiride in olfactory tubercle. Also, the increase in $K_D$ was significant after treatment with haloperidol and sulpiride in olfactory tubercle. Moreover, the $K_D$ of control group in olfactory tubercle was more than twice the $K_D$ of control group in striatum. The $K_D$ was 86.2 in striatum and 37.5 pM in olfactory tubercle. The present finding indicates that sulpiride also induces the proliferation of DA receptor in olfactory tubercle and may interact with some DA receptor subtype with high affinity profile. The different affinities of the control groups of striatum and olfactory tubercle suggest that striatal DA receptor subtypes labeled by [$^3H$]spiperone could differ from those of olfactory tubercle.

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