• 한국연소학회:학술대회논문집
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• 2004.06a
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• pp.165-172
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• 2004

Co-incineration of coal and wastewater sludge was r;erfonn:rl in a O.lMWth bench scale circulating fluidized bed combustor(CFBC) Sludge was received from a wastewater treatment plant in a dye industrial complex in Busan. Metropolis. Moisture content of received sludge was 80%. Coal and sludge mixture was prepared with weight ratio of 90/10, 85/15 and 80/20. Co-combustion characteristics of the coal and sludge mixture demonstrated stable combustion conditions. Component analysis, incineration characteristics, boiler performance was measured before and after the test and application for commercial 59MWth CFBC boiler. The release of hazardous components such as $SO_2$ and Cl was suppressed by the presence of inherent minerals of Ca, Na, K in coal and sludge mixture. Pre-drying was not essential but it was recommended for the benefits of manageability of sludge.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.2
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• pp.107-120
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• 2021

The Komdok Pb-Zn deposit, which is the largest Pb-Zn deposit in Korea, is located at the Hyesan-Riwon metallogenic zone in Jiao Liao Ji belt included Paleoproterozoic Macheolryeong group. The geology of this deposit consists of Paleoproterozoic metasedimentary rocks, Jurassic Mantapsan intrusive rocks and Cenozoic basalt. The Komdok deposit which is a SEDEX type deposit occurs as layer ore and vein ore in the Paleoproterozoic metasedimentary rocks. Based on mineral petrography and paragenesis, dolomites from this deposit are classified four types (1. dolomite (D₀) as hostrock, 2. early dolomite (D₁) associated with tremolite, actinolite, diopside, sphalerite and galena from amphibolite facies, 3. late dolomite (D₂) associated with talc, calcite, quartz, sphalerite and galena from amphibolite facies, 4. dolomite (D₃) associated with white mica, chlorite, sphalerite and galena from quartz vein). The structural formulars of dolomites are determined to be Ca_1.00-1.20Mg_0.80-0.99Fe_0.00-0.01Zn_0.00-0.02(CO₃)₂(D₀), Ca_1.00-1.02M_0.97-0.99Fe_0.00-0.01Zn_0.00-0.02(CO₃)₂(D₁), Ca_0.99-1.03Mg_0.93-0.98Fe_0.01-0.05Mn_0.00-0.01As_0.00-0.01(CO₃)₂(D₂) and Ca_0.95-1.04Mg_0.59-0.68Fe_0.30-0.36Mn_0.00-0.01 (CO₃)₂(D₃), respectively. It means that dolomites from Komdok deposit have higher content of trace elements (FeO, MnO, HfO₂, ZnO, PbO, Sb₂O₅ and As₂O₅) compared to the theoretical composition of dolomite. These trace elements (FeO, MnO, ZnO, Sb₂O₅ and As₂O₅) show increase and decrease trend according to paragenetic sequence, but HfO₂ and PbO elements no show increase and decrease trend according to paragenetic sequence. Dolomites correspond to Ferroan dolomite (D₀, D₁ and D₂), and Ferroan dolomite and ankerite (D₃), respectively. Therefore, 1) dolomite (D₀) as hostrock was formed by subsequent diagenesis after sedimentation of Paleoproterozoic (2012~1700 Ma) silica-bearing dolomite in the marine evaporative environment. 2) Early dolomite (D₁) was formed by hydrothermal metasomatism origined metamorphism (amphibolite facies) associated with intrusion (1890~1680 Ma) of Paleoproterozoic Riwon complex. 3) Late dolomte (D₂) was formed from residual fluid by a decrease of temperature and pressure. and dolomite (D₃) in quartz vein was formed by intrusion (213~181 Ma) of Jurassic Mantapsan intrusive rocks.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.281-290
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• 2018

In order to understand the long-term behavior of radionuclides in granite environments, geochemical behavior characteristics of uranium in granitic host rock of KURT (KAERI Underground Research Tunnel) were investigated by dissolution experiment with different reaction time and solutions. In the dissolution experiment, significantly increased dissolution levels of uranium from granite powder samples were identified during the reaction time of 0~10 days for reaction solutions ($UD-CO_3$ and UD-Bg) containing a large amount of $CO_3{^{2-}}$. On the other hand, significantly increased dissolution levels of uranium were also identified for reaction solutions containing Na and Ca after 60 days. Dissolution of uranium continuously increased in reaction solutions of $UD-CO_3$ ($44.61{\mu}g{\cdot}L^{-1}$), UD-Bg ($41.01{\mu}g{\cdot}L^{-1}$), UD-Na ($26.87{\mu}g{\cdot}L^{-1}$), UD-Ca ($20.26{\mu}g{\cdot}L^{-1}$), UD-CaSi ($17.03{\mu}g{\cdot}L^{-1}$), and UD-Si ($10.47{\mu}g{\cdot}L^{-1}$) in the experimental period of ~270 days. However, after day 270, dissolution of uranium showed a decreasing tendency. This is thought to have occurred because existing uranium in granite samples reached the limit of dissolution by interaction with reaction solutions. Concentrations of dissolved uranium and points of maximum concentration value were found to differ depending on the $CO_3{^{2-}}$ presence in the mixed reaction solution and on the geochemical type of the water. It is estimated that differences in the reaction rate between the granite sample and the reaction solution are due to the influence of dissolved ions in the reaction solution.

• Journal of Food Hygiene and Safety
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• v.18 no.3
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• pp.146-152
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• 2003

Pyruvate dehydrogenase phosphatase (PDP) is a mitochondrial protein serine/threonine phosphatase that catalyzes the dephosphorylation and concomitant reactivation of the pyruvate dehydrogenase component of the pyruvate dehydrogenase complex (PDC). PDP consists of a catalytic subunit (PDPc, Mr 52,600) and regulatory subunit (PDPr, Mr 95,600). In the presence of $Ca^{2+}$, PDPc binds to the dihydrolipoamide acetyltransferase (E2) component of the pyruvate dehydrogenase complex in proximity to its substrate, the phosphorylated E1 component, thereby increasing the rate of dephosphorylation. PDPc possesses and intrinsic $Ca^{2+}$ binding site and a second $Ca^{2+}$ site is generated in the presence of E2. Using the unique interaction, highly pure PDPc was produced by the GSH-Sepharose-GST-L2 matrix with a specific activity of approx. 1000 U/mg and a yield of about 80%.

• Childhood Kidney Diseases
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• v.9 no.1
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• pp.76-82
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• 2005

Purpose : Regional anticoagulation with trisodium citrate for continuous renal replacement therapy(CRRT) is an effective and safe method, with lower bleeding risk. However it is not widely used because of complex current protocols used to prevent anticipated metabolic derangements. We evaluated simplified regional anticoagulation protocols with ACD-A(R) solution and commercially available calcium-containing dialysis solution. Methods : The medical records of twenty-eight patients who underwent CRRT were reviewed. Hemofilter life span according to the anticoagulation method used was compared, and laboratory findings at Pre- and 48 hours post-CRRT initiation were compared in the citrate-based CRRT group. Results : Of the twenty-eight Patients, five patients underwent citrate-based CRRT Hemofilter life span was 1.60 $\pm$ 0.72 days, showing no significant differences with the hemofilter life span in the heparin based and LMWH based CRRT group. No patients experienced hemorrhagic complications. PT, aPTT, sodium, t$CO_{2}$, iCa levels showed no difference in pre- and post-CRRT. Total calcium levels were increased. At the recommended postfilter iCa level, j.e., 0.25-0.39 mmol/L, all five patients needed increased amount of citrate infusion, and Ca infusion requirement was decreased. Conclusion : Simplified regional citrate anticoagulation with calcium-containing dialysate is an effective and safe method, and is not associated with increased hemofilter clotting. However, increased postfilter iCa level is recommended.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.138-147
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• 2010

Nematicidal activity against pine wood nematode, Bursaphelenchus xylophilus, was tested in the pot and field by the treatment of microbial formulation after media optimization. The optimized media composition was glycerol 10 g, soybean meal 10 g, NaCl 1 g, $CaCO_3$ 2 g, $K_2HPO_4$ 0.125 g per liter and microbial complex formulation was made with liquid and powder type. Most effective antibiotics against symbiotic microorganism with nematode, kanamycin, was added to the formulation. The control effects against pine wood nematodes were checked by pot test and field test. In the result of treatment by trunk injection, five times treatment was more effective than one time and the treatment with the formulation of concentrated culture supernatant was the most effective in the nematicidal activity showing below 10% mortality in pine tree.

• Molecules and Cells
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• v.43 no.9
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• pp.831-840
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• 2020

The β-class of carbonic anhydrases (β-CAs) are zinc metalloenzymes widely distributed in the fungal kingdom that play essential roles in growth, survival, differentiation, and virulence by catalyzing the reversible interconversion of carbon dioxide (CO₂) and bicarbonate (HCO₃^-). Herein, we report the biochemical and crystallographic characterization of the β-CA CafA from the fungal pathogen Aspergillus fumigatus, the main causative agent of invasive aspergillosis. CafA exhibited apparent in vitro CO₂ hydration activity in neutral to weak alkaline conditions, but little activity at acidic pH. The high-resolution crystal structure of CafA revealed a tetramer comprising a dimer of dimers, in which the catalytic zinc ion is tetrahedrally coordinated by three conserved residues (C119, H175, C178) and an acetate anion presumably acquired from the crystallization solution, indicating a freely accessible "open" conformation. Furthermore, knowledge of the structure of CafA in complex with the potent inhibitor acetazolamide, together with its functional intolerance of nitrate (NO₃^-) ions, could be exploited to develop new antifungal agents for the treatment of invasive aspergillosis.

• The Journal of Engineering Geology
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• v.13 no.1
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• pp.1-16
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• 2003

Geochemical characteristics of groundwater in the different kinds of various lithology such as Haman formation, Panyaweol formation, Jusan andesitic formation and Palgongsan granite is distinguished by mineralogical and chemical compositions. The Concentration of the majority of solutes in groundwaters of Haman and Panyaweol formation is higher than in that of andesite and granite. Higher concentration of $HCO_3^{-}{\;}and{\;}SO_4^{2-}$ anions in the groundwater is peculiar. High concentrations of $Ca^{2+},{\;}Mg^{2+},{\;}HCO_3^{-}$ in the groundwaters of the sedimentary rocks result mainly from reaction of $CO^{2-}$ charged water with calcite and weathered feldspars. With the Piper diagram, the groundwaters of Haman formations are mainly plotted in $CaSO_4-CaCl_2$ type, whereas those of Panyaweol formations are plotted in the bothside of $Ca(HCO_3)_2{\;}and{\;}CaSO_4-CaCl_2$ type. Thses two different types of $Ca(HCO_3)_2{\;}and{\;}CaSO_4-CaCl_2$ groundwater were originated from dissolution of calcite($Ca(HCO_3)_2)$ and the oxidation of pyrite($CaSO_4-CaCl_2$), respectively. And it also is influenced by anthropogenic contamination. Three factors were extracted from the factor analysis for chemical data. Factor 1, controlled by $SO_4^{2-},{\;}Na^{+},{\;}Ca^{2+}$ and Fe, explains the dissolution of calcite, plagioclase and oxidation of pyrite. Factor 2, controlled by $HCO_3^{-}{\;}and{\;}Mg^{2+}$, mainly explains the dissolution of Mg-carbonates and dolomitization. Factor 3, controlled by $Cl^{-},{\;}K^{+}{\;}and{\;}NO_3^{-}$, is subject to the influence of artificial pollution including industrial waste water disposal. In this study area, some industrial complex which is close to Keumho river show the higher score of factor 3.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.155-158
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• 1989

The rates of complexation of the 18-C-6 (1,4,7,10,13,16-hexaoxacyclooctadecane) with $K^+,\;Ca^{2+},\;Sr^{2+},\;and\;Ba^{2+}$ in methanol solution have been determined at 25$^{\circ}C$ by a pressure-jump technique. The Eigen Winkler mechanism has been applied to interprete the kinetic data. The results suggest that the rate determining step of the complexation in methanol is the rearrangement of the ligand in the outer sphere ion-dipole pair to form a stable encapsulated complex of the metal ion by the crown ether.

• Korean Journal of Pharmacognosy
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• v.33 no.4 s.131
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• pp.389-394
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• 2002

Present study was carried out for development of a new supplementary product with gastroprotective effect. Natural Products mentioned that have GI protective property in Dongeuibogam and reports were evaluated anti-bacterial activity against Helicobacter pylori, then five heres were selected. The material used for the test were water extract of Alpinia oxyphlla (AO), Astragalus membranaceus (AM), Cinnamomum loureirii(CL), Citrus aurantium(CA), Amomum villosum(AV). They were tested individually on HCI ethanol-induced gastric lesion in rats, AV CL, AO showed the most significant effectiveness, respectively. Then two mixture different in their content ratio (P020701-1,-2) and complex with P020701-1 (CP) were made, and tested on HCI·ethanol, indomethacin-induced gastric lesion, aspirin-ligature, Shay ulcer and gastric secretion. P020701-1, -2 and CP showed significant effect on HCI ethanol, indomethacin-induced gastric lesion, and Shay ulcer. It can be regarded that the antigasuitic and anti-ulcerative effects of P020701- 1, -2 and CP are originated from reduction of total acid output identified by gastric secretion test.