• Title/Summary/Keyword: Hydrogen ion concentration

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Formation of Acid Mine Drainage and Pollution of Geological Environment Accompanying the Sulfidation Zone of Nonmetallic Deposits: Reaction Path Modeling on the Formation of AMD of Tongnae Pyrophyllite Mine (비금속광상의 황화광염대에 수반되는 산성광산배수의 형성과 지질환경의 오염 : 동래납석광산 산성광산배수의 형성에 관한 반응경로 모델링)

  • 박맹언;성규열;고용전
    • Economic and Environmental Geology
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    • v.33 no.5
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    • pp.405-415
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    • 2000
  • This study was carried out to understand the formation of acid mine drainage (AMD) by pyrophyllite (so-called Napseok)-rainwater interaction (weathering), dispersion patterns of heavy metals, and patterns of mixing with non-polluted water in the Tongnae pyrophyllite mine. Based on the mass balance and reaction path modeling, using both the geochemistry of water and occurrence of the secondary minerals (weathering products), the geochemical evolution of AMD was simulated by computer code of SOLVEQ and CHILLER. It shows that the pH of stream water is from 6.2 to 7.3 upstream of the Tongnae mine. Close to the mine, the pH decreases to 2. Despite being diluted with non-polluted tributaries, the acidity of mine drainage water maintains as far as downstream. The results of modeling of water-rock interaction show that the activity of hydrogen ion increases (pH decreases), the goncentration of ${HCO_3}^-$ decreases associated with increasing $H^+$ activity, as the reaction is processing. The concentration of ${SO_4}^{2-}$first increases minutely, but later increases rapidly as pH drops below 4.3. The concentrations of cations and heavy metals are controlled by the dissolution of reactants and re-dissolution of derived species (weathering products) according to the pH. The continuous adding of reactive minerals, namely the progressively larger degrees of water-rock interaction, causes the formation of secondary minerals in the following sequence; goethite, then Mn-oxides, then boehmite, then kaolinite, then Ca-nontronite, then Mgnontronite, and finally chalcedony. The results of reaction path modeling agree well with the field data, and offer useful information on the geochemical evolution of AMD. The results of reaction path modeling on the formation of AMD offer useful information for the estimation and the appraisal of pollution caused by water-rock interaction as geological environments. And also, the ones can be used as data for the choice of appropriate remediation technique for AMD.

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Relationships of Pathogenic Vibrios and Environmental Factors Affecting their Occurrence in the Seawater of Incheon Coastal Area (인천 연안지역의 해양환경요인과 병원성 비브리오균의 분포와의 관련성)

  • Go, Yeon-Ja;Jang, Jae-Seon
    • The Korean Journal of Food And Nutrition
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    • v.26 no.3
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    • pp.414-420
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    • 2013
  • The aim of this study was to investigate the effects of environmental factors such as temperature, salinity, turbidity and pH on the growth of pathogenic Vibrios. In this study, we was obtained the samples from 2 different sites of the Incheon coastal area between January 2012 and December 2012. The water temperature in August and September was the high. the Incheon port changes the width of a small, wherease in the case of Hanjin harbor of changes of larger width. Salinity and turbidity showed significant differences, whereas temperature and hydrogen ion concentration was not significant. Pathogenic vibrios was determined using the real-time PCR method. Pathogenic vibrios in the Incheon port and Hanjin harbor were detected in 11 samples (91.67%) and 9 samples (75.0%) of Vibrio cholerae, 7 samples (58.3%) and 6 samples (50.0%) of V. vulnificus, 10 samples (83.3%) and 12 samples (100.0%) of V. parahaemolyticus, respectively. Pathogenic Vibrio bacteria were the highest at $26.8^{\circ}C$ of seawater in August. Quantitative results were the following: 102 $cell/m{\ell}$ in Vibrio cholerae, 7.876 $cell/m{\ell}$ in V. vulnificus, and 503.4 $cell/m{\ell}$ in V. parahaemolyticus, respectively. The enumeration of pathogenic vibrios showed a positive correlation with temperature and pH, but was negatively correlated with salinity and turbidity.

The Failure Analysis of Double Pipe for Insulation Used Power Plant by Grooving Corrosion (발전소용 이중보온용 강관의 홈부식(Grooving Corrosion)에 의한 파손 분석)

  • Ham, Jong-Oh;Park, Ki-Duck;Park, Sung-Jin;Sun, Il-Sik
    • Journal of Applied Reliability
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    • v.15 no.3
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    • pp.197-206
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    • 2015
  • Failure analysis of pre-insulated pipe (SPPS 380, 400A) transporting high temperature water ($95{\sim}110^{\circ}C$) for a plant was carried out. The damaged area (${\Phi}5mm$) of pre-insulated pipe was found only on welds. The chemical composition of damaged pipe meets specification of carbon steel pipes for pressure service (KS D 3562). As results of microstructure analysis, crack propagated from outer to inside after pitting corrosion occurred on the outside surface. The non-metallic inclusion existed on the end of crack. And the non-metallic inclusion continuously and linearly formed along with the bond line of welds. Based on SEM-EDS analysis, the nonmetallic inclusions have higher Manganese (Mn) and Oxygen (O) content but sulfur (S) was not detected. As results of water quality analysis, hydrogen ion concentration and minerals like Fe, Mg, Si were in low level. But the content of dissolved oxygen (11.2 ppm) was slightly higher than that of standard. It seems that the cause of damaged pipe is grooving corrosion due to MnO inclusion formed on bond line and corrosion took place nearby welds.

Investigation of difference of Gwakhyangjeonggi-san decoctions produced by different pressure levels and various extraction times (전탕 압력과 전탕 시간의 차이에 따른 곽향정기산 전탕액 비교)

  • Kim, Jung-Hoon;Lee, Nari;Shin, Hyeun-Kyoo;Seo, Chang-Seob
    • Herbal Formula Science
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    • v.22 no.2
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    • pp.15-24
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    • 2014
  • Objectives : Gwakhyangjeonggi-san (GJS) which consists of 13 herbal medicines has been used to treat gastrointestinal disorders caused by common cold. This study was performed to compare GJS decoctions produced using different pressure levels for various extraction times. Methods : Decoctions were prepared by the pressure levels of $0kgf/cm^2$ (non-pressurized) or $1kgf/cm^2$ (pressurized) for 30-180 min. The extraction yield, total soluble solid content (TSSC), and hydrogen ion concentration (pH) were measured, and the contents of the nine marker compounds were determined using high performance liquid chromatography. Results : The higher pressure and longer extraction time significantly increased TSSC value, while decreased the pH value. However, only extraction time affected the extraction yield of pressurized decoction. Variation of the amounts of chemical compounds was shown in pressurized and non-pressurized decoctions during extraction time. The result of regression analysis showed that pressure and extraction time can influence to extraction yield, TSSC, pH, and the content of chemical compounds. Conclusions : This study suggests that the pressure and extraction time can significantly affect the extraction efficiency of components from GJS decoctions.

Effects of Oketani Breast Massage on Breast Pain, the Breast Milk pH of Mothers, and the Sucking Speed of Neonates

  • Cho, Jeong-Sug;Ahn, Hye-Young;Ahn, Suk-Hee;Lee, Myeong-Soo;Hur, Myung-Haeng
    • Women's Health Nursing
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    • v.18 no.2
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    • pp.149-158
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    • 2012
  • Purpose: This study was done to test the effects of Oketani breast massage on breast pain and breast milk pH of mothers, and sucking speed of neonates. Methods: A nonequivalent control group and a pretest-posttest design was used. Postpartum mothers complaining of breast pain were recruited at a postpartum care center. The application of Oketani breast massage by an Oketani massage therapist was the experimental treatment. The control group received the conventional massage technique from a nurse at the postpartum care centre. The collected data were analysed using a $x^2$-test and a t-test with the SPSS WIN 12.0 program. Results: The participants were homogeneous in age, gestation period, and birth weight. Breast pain (t=8.384, p<.001) was significantly relieved, and breast milk pH (t=4.793, p<.001) was significantly increased in the experimental group compared to the control group. The sucking speed of the neonates in the experimental group was significantly increased compared to the control group (t=9.920, p<.001). Conclusion: These findings indicate that Oketani breast massage is effective in relieving breast pain and increasing breast milk pH as well as the sucking speed of neonates.

A Study on the Formation of Hydrous Ferric Oxide from Ferrous Sulfate (黃酸第一鐵로부터 含水酸化鐵生成에 關한 硏究)

  • Sung Joo Kyung;Suhl Soo Duk;Whang Yong Kil
    • Journal of the Korean Chemical Society
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    • v.19 no.2
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    • pp.142-146
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    • 1975
  • The formation of iron oxide hydroxide in a ferrous sulfate was studied in different contents of iron in the solution at a temperature range of 90 to $100^{\circ}C$ under 1${\sim}$3 atmospheres. The Mohr's salt thus formed was hydrolyzed under 1 to 3 atmospheres, in 14 to 72 g/l of iron content in the solution pH 3 or 6 for two hours at 90 to $100^{\circ}C$. The results obtained was as follows; 1) In Mohr's salt solution, as the iron content was increased, with decreasing the concentration of hydrogen ion, the yield of iron oxide hydroxide was gradually increased. 2) When iron content in Mohr's salt solution was 42.81 g/l, 91.5% of iron was recovered in the form of $\alpha$-goethite similar to yellow grade of natural goethite. 3) When $\alpha$-goethite obtained was calcined of $500^{\circ}C$, it was turned into ${\alpha}$-ferric oxide with a redish brown colour.

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The biochemical constituents and their changes during the fermentation of Takju mashes and Takju (탁주 및 탁주료의 화학성분과 그 변화에 관한 연구)

  • 홍순우;하영칠;민경희
    • Korean Journal of Microbiology
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    • v.8 no.3
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    • pp.107-115
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    • 1970
  • In order to brew Takju, Korean flour wine, it requires three necessary steps for specific brewage. One is primary brewing process and another main brewing process to sacharify and perform alcoholic fermentation. After previous two brewing passing, the mash of main brewing process mixed with 1 volume of water is commercial Takju. Three samples were obtained from three breweries and incubated at $28{\pm}1^{\circ}C$for the alcoholic fermentation. All the samples were analyzed for observation of the changes of various biochemical constituents which were contained in the mashes of two brewing processes and in Takju. The starch contents of the suspensions in the primary and main mashes, and in Takju were 28.08, 25.92, 3.83%, and decreased considerably within 36-48 hrs and thereafter slowly. The amounts of water soluble carbohydrates and reducing sugars in three steps had a tendency of decreasing within 48 hours. The initial numbers of yeasts per 1ml in the suspensions were $1.74{\times}10^8$, $1.65{\times}10^8$, $0.66{\times}10^8$, appeared the highest at 72 hours (12.66%) in main process, and in the case of Takju kept increasing untill 60 hours. The dextrin contents in the mashe of primary process through the long period were 0.34 - 0.68%, in the main one were 0.12 - 0.32%, concerning with the amylase activities which were stronger in the mash of the primary process than in that of the main. The contents of methanol and cellulose in the mashes of two processes were 3.40-0.68%, in the main one were 0.12-0.32%, concerning with the amylase activities which were stronger in the mash of the primary process than in that of the main. The contents of methanol and cellulose in the mashes of two processes were 3.40-5.98mg/ml, 0.43-0.48% during the fermentation. The consumption of crude protein the mashes of Takju revealed with time, on the contrary, the production of free amino acids and oligo-peptides were performed, depending upon the affection of proteinase. The amount of tannic acid in Takju was 0.0073-0.0098mg/ml and organic acids of these three groups increased with time and hydrogen ion concentration was 3.28-4.43.

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The Compositional Differences of Sipjeondaebo-tang(Siquandabu-tang) Decoctions Extracted by Different Extraction Method and Extraction Time (전탕 방법 및 전탕 시간에 따른 십전대보탕 전탕액 비교 연구)

  • Kim, Jung-Hoon;Seo, Chang-Seob;Jeon, Woo-Young;Shin, Hyeun-Kyoo
    • The Journal of Korean Obstetrics and Gynecology
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    • v.25 no.2
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    • pp.108-119
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    • 2012
  • Objectives: This study was performed to compare the differences between decoctions extracted by different extraction method and extraction time. Methods: Decoctions were prepared with pressurized or non-pressurized extraction for 60, 120 and 180min. The yield of extract, total soluble solid content, hydrogen ion concentration(pH) and the content of reference compound in Sipjeondaebo-tang (Siquandabu-tang) were investigated. Results: While yields and the total soluble solid of decoction were higher in pressurized method proportional to extraction time, pH values were lower in pressurized method and showed decreasing values with increasing extraction time. Albilflorin, ferulic acid, nodakenin, coumarin, cinnamaldehyde and glycyrrhizin were contained in decoctions by pressurized extraction method more than non-pressurized method whereas the content of coumarin was higher in decoctions by non-pressurized extraction method. In addition, coumarin was extracted increasingly with extraction time in decoctions by pressurized method, however, nine compounds except cinnamaldehyde showed the tendency of increasing proportional to extraction time. Conclusions: The results show that extraction methods including pressurized or non-pressurized extraction, and extraction time could affect the physicochemical characteristic or composition of Sipjeondaebo-tang(Siquandabu-tang) decoction.

Development of a complex sensor software for measuring the exhaustion rate of dyeing factories (염색공장의 흡진율 계측을 위한 복합센서 흡진율 계측 모델 개발)

  • Lee, Jeong-in;Park, Wan-Ki;Kim, Sang-Ha
    • Journal of IKEEE
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    • v.26 no.2
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    • pp.219-225
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    • 2022
  • The textile industry in Korea, the dyeing sector is an energy-intensive sector and has low per-unit productivity due to its labor-intensive nature. If the defective rate of dyed fabrics is high, additional costs are incurred due to an increase in production cost due to re-dyeing. Therefore, the goal of the dyeing factory was to minimize the defect rate rather than to save energy. It was difficult to check the dyeing state of the fabric in real time due to the risk of accidents due to burns or pressure when dyeing in a high-temperature and high-pressure environment. In this paper, a complex sensor that can measure the exhaustion rate of dye solution in the dyeing machine using turbidity, pH, and conductivity sensors was proposed, and the experimental method and experimental results were analyzed.

Optimal Condition of Operation Parameter for Livestock Carcass Leachate using Fenton Oxidation Process (가축 사체 매몰지 침출수 처리를 위한 Fenton 산화공정의 최적조건)

  • An, Sang-Woo;Jeong, Young-Cheol;Yoo, Ji-Young;Min, Jee-Eun;Lee, Si-Jin;Park, Jae-Woo
    • Journal of Soil and Groundwater Environment
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    • v.18 no.1
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    • pp.26-35
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    • 2013
  • Outbreak of animal infectious diseases such as foot-and-mouth disease, avian influenza are becoming prevalent worldwide. For prevent the further infection, tremendous numbers of the infected or culled stocks are buried around farm. This burial method can generate a wide range of detrimental components such as leachate, nutrient, salt, and pathogenic bacteria, consequently. In this study, for the stabilization of livestock carcasses leachate, advanced oxidation processes utilizing the Fenton reaction was investigated in lab-scale experiments for the treatment for $COD_{Cr}$ of livestock carcass leachate. $COD_{Cr}$ reduction by the Fenton oxidation was investigated response surface methodology using the Box-Begnken methods were applied to the experimental results. A central composite design was used to investigate the effects of the independent variables of pH ($x_1$), dosage of $FeCl_2{\cdot}4H_2O$ ($x_2$) and dosage of $H_2O_2$ ($x_3$) on the dependent variables $COD_{Cr}$ concentration ($y_1$). A 1 M NaOH and $H_2SO_4$ was using for pH control, $FeCl_2{\cdot}4H_2O$ was used as iron catalyst and NaOH was used for Fenton reaction. The optimal conditions for Fenton oxidation process were determined: pH, dosage of $FeCl_2{\cdot}4H_2O$ and dosage of $H_2O_2$ were 3, 0.6 g (0.0151 M) and 7 mL(0.259 M), respectively. Statistical results showed the order of significance of the independent variables to be pH > initial concentration of ferrous ion > initial concentration of hydrogen peroxide.