• Title/Summary/Keyword: high pH

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전남(全南) 옥매산광상(玉埋山鑛床)의 열수변질작용(熱水變質作用) 및 광석광물(鑛石鑛物)에 대한 광물학적(鑛物學的) 연구 (Hydrothermal Alteration and Mineralogy of Alunite and Kaolinite in the Ogmae Deposit, Southwest Jeonnam)

  • 김영희;문희수;김종환;유장한;김인준
    • 자원환경지질
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    • 제23권3호
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    • pp.287-308
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    • 1990
  • The Ogmae alunite-kaolinite deposit occurs in acidic tuff, the Hwangsan Tuff, of upper Crataceous age in the Haenam volcanic field, SW Jeonnam. This deposit characterized by advanced argillic alteration formed $71.8{\pm}2.8{\sim}73.9{\pm}2.8$ Ma ago in very shallow depth environment with acid-sulfate solution. Wallrock alteration can be classified into four zones from the center to the margin of the deposit: alunite, kaolinite, illite, and silicified zone. The mineral assemblage in the alunite zone, ore zone, is alunite-quartz-pyritekaolinite. Consideration of stability relation of these minerals suggests that the maximum alteration temperature is estimated at about $250^{\circ}C$ with solution pH of 3 or below assuming that pressure does not exceed 0.3 Kb. Alunite occurs as two different types; replacement and vein-type deposit. The former one consists of fine grained alunite and the later one coarse grained and relatively pure alunite that formed by open space filling. Isomorphous substitution of Na for K in these two types of alunites range 0 to 40 %, indicating that Na/K ratio in the solution is spontaneously changed during the alteration process. Alunite which has higher Na substitution probably formed in an earlier stage while the solution sustain high Na/K ratio. K-Ar age of alunites indicate that the replacement alunite formed earlier($73.9{\pm}2.8Ma$) than the vein-type alunite($71.8{\pm}2.8Ma$). The ${\delta}^{34}S$ value of pyrite and alunite indicate that those minerals formed at isotopically nonequillibrium state. The ${\delta}^{16}O$ and ${\delta}D$ values, of kaolintics 5.0 to 9.0‰ and -54 to -99‰, respectively, indicate that those are formed by hydrothermal solution having magmatic origin which have been diluted by low ${\delta}D$ meteoric water.

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사회복지전담공무원의 외상사건 및 스트레스 대처방식과 외상후스트레스증상 관련성 (Relationship between Traumatic Events, Stress Coping Strategies and Post-Traumatic Stress Symptoms among Social Workers in Public Sector)

  • 이정현;김지애;심민영;전경선;오승아;양정일;이영렬
    • 생물정신의학
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    • 제22권2호
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    • pp.55-62
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    • 2015
  • Objectives Social workers can suffer from occupational stress resulting from dealing with clients, which might lead to metal health problems. We aimed to investigate the association of duty-related traumatic experiences and stress coping strategies with post-traumatic stress symptoms among social workers in public sector. Methods A total of 110 social workers in public sector (men 30.9%, $36.5{\pm}7.6$ yrs) participated in this study. All subjects were evaluated the frequency and the impact of duty-related traumatic events. Additionally, they completed questionnaires including the Impact of Event Scale-Revised for post-traumatic stress symptoms, the Beck Depression Inventory-II for depressive symptoms, the Scale for Suicidal Ideation for suicide symptoms and the Ways of Coping Checklist for stress coping strategies. Results The most frequent traumatic events were "Violent or abusive language from a client" (95.0%) and "Client made a fuss" (94.5%). The most distressing traumatic event was "Seeing a dead body on duty" (7.6 out of 10), which predicted post-traumatic stress symptoms (odds ratio 4.04 ; 95% confidence interval, 1.79-9.11). Among 4 types of stress coping strategies, the emotion-focused coping was positively correlated with post-traumatic stress symptoms after controlling age and sex (${\beta}$ = 0.50, p < 0.001). Conclusions Social workers in public sector showed high level of post-traumatic stress symptoms. Duty-related traumatic events and the emotional-focused coping strategies were associated with the severity of post-traumatic stress symptoms. The modification of stress coping strategies would alleviate post-traumatic stress symptoms in social workers in public sector.

습지식물의 적정 서식 환경 : I. 줄과 애기부들 (The Optimal Environmental Ranges for Wetland Plants : I. Zizania latifolia and Typha angustifolia)

  • 권기진;이보아;변채호;남종민;김재근
    • 한국환경복원기술학회지
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    • 제9권1호
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    • pp.72-88
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    • 2006
  • The optimal environmental ranges of the establishment phase for the distribution of Zizania latifolia and Typha angustifolia was determined to develop a set of basic data and criteria of planting substrate for the restoration, conservation and management of wetlands. The study was carried at 17 wetlands in the Kyunggi-do and Gyeongsangnam-do region where inland wetlands place intensively in June, 2005. Total 127 quadrats were sets in growing areas of Zizania latifolia and Typha angustifolia. $NO_3-N$, K, Ca, Mg and Na in the water variables and soil texture, LOI (loss on ignition), soil pH and soil conductivity in the soil variables were analyzed. The optimal range of water depth for the distribution of Zizania latifolia was -5~39cm, $NO_3-N$ content of water was <0.01~0.19ppm, K content of water was 0.1~5.9ppm, Ca content of water 0.5~44.9ppm, Mg content of water was 1.2~11.9ppm, Na content of water 3.4~29.9ppm, water conductivity was 48~450${\mu}S$/cm, respectively. The optimal range of LOI for the distribution of Zizania latifolia was 1.7~11.9%, soil conductivity was 25.5~149.9${\mu}S$/cm, respectively. The optimal range of water depth for the distribution of Typha angustifolia was -20~24cm, $NO_3-N$ content of water was <0.01~0.19ppm, K content of water was 0.2~2.9ppm, Ca content of water 0.6~19.9ppm, Mg content of water was 0.2~5.9ppm, Na content of water 3.5~19.9ppm, water conductivity was 96~450${\mu}S$/cm, respectively. The optimal range of LOI for the distribution of Typha angustifolia was 2.4~15.9%, soil conductivity was 17.6~149.9${\mu}S$/cm, respectively. The optimal soil texture were loam, silt loam and sandy loam in both species. The lower water depth (-20~40cm) is appropriate to increase biodiversity in both species dominated community and it is better to maintain water depth of 40~100cm for water purification. Both species appear frequently in the soil with high silt content.

제주연안 육상양식장 밀집지역 주변해역의 영양염 과잉 요인 (Coastal Eutrophication caused by Effluent from Aquaculture Ponds in Jeju)

  • 고혁준;박성은;차형기;장대수;구준호
    • 해양환경안전학회지
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    • 제19권4호
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    • pp.315-326
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    • 2013
  • 제주연안선 부근에 밀집된 육상양식장 배출구 주변 4개 해역(애월리, 행원리, 표선리, 일과리)에서 수질환경의 시공간적 변화에 영향을 미치는 요인을 파악하기 위해 2010년 2월부터 2011년 12월까지 격월로 총 12회 조사하였다. 주성분 분석 결과 조사해역에서 연중 영양염의 분포는 염분과의 관련성 없이 배출구로부터 공급되는 물질에 의해 영양염의 농도가 조절되어, 연안에서 외해역으로 갈수록 농도구배가 감소하는 특징을 나타냈다. 특히 용존무기질소의 경우는 배출구와 인접한 해역에서는 부영양상태로 인에 비해 질소가 과잉되고 있었다. 유기물의 분포는 담수유입량이 증가하는 고수온기에 증가하는 경향을 보였다. 식물플랑크톤의 생물량 변화는 애월 및 행원해역은 담수유입과 관련된 기상요인(기온 및 강우), 표선 및 일과는 영양염의 인위적 공급요인(양식장 배출수)에 의한 영향을 주로 받는 것으로 나타났다. 특히, 배출구로부터 직선거리 약 300 m 및 수심 10 m이내 해역의 표 저층에서는 고영양염 농도 분포가 지속되고 있어, 부영양화 과정에서 발생하는 문제를 직 간접적으로 받을 수 있는 가능성을 나타냈다. 육상양식장의 운영 시 취수지점이 배출수의 영향을 받는 지점에 위치할 경우 사육수질의 문제가 발생할 수 있다.

NF/RO 멤브레인 공정을 적용한 고체추진제에서 추출된 암모늄 퍼클로레이트 (AP) 처리 연구 (Treatment of AP Solutions Extracted from Solid Propellant by NF/RO Membrane Process)

  • 공충식;허지용;윤여민;한종훈;허남국
    • 멤브레인
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    • 제22권4호
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    • pp.235-242
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    • 2012
  • 로켓 추진기관의 해체 시 발생하는 고농도 암모늄 퍼클로레이트(AP)를 액상소각 처리 후 추가로 발생하는 저농도의 AP처리를 위해 NF/RO 멤브레인 공정을 적용하였고, 이때 AP제거 특성에 영향을 미치는 인자를 도출하기 위해 다양한 수리화학적 조건에서 전량여과방식으로 실험을 진행하였다. 고체 추진제에서 추출된 용액을 GC/MS와 FTIR분석을 통해 규산염 계열의 실록산 등을 검출하였으나, 이는 극미량이 포함되어 NF/RO 멤브레인 공정에 큰 영향을 미치지 않는 것으로 판단되었다. 상대적으로 낮은 압력의 운용조건에서는 높은 압력조건과 비교하여, 회수율 증가에 따라 농축된 AP의 삼투압 기작이 투과플럭스에 영향을 미치게 되어 13~17% 가량 플럭스가 감소됨을 확인하였다. 또한 AP의 제거율은 수리화학적 운영조건의 변화(압력 및 교반 속도 등)에 따라 크게 좌우됨을 알 수 있었고, 이 경우 NF와 RO 멤브레인 제거율은 각각 10~70%와 26~87% 가량 크게 달라짐을 확인하였다. 본 논문을 통해 NF/RO 멤브레인 공정을 적용한 AP 제거 기작에서 수리화학적 운영조건의 변화에 따른 농도분극, 멤브레인 선택성 및 삼투압 영향이 중요 지배 기작이었으며, 이는 'NF/RO 멤브레인의 물질이동과 선택성'의 기존 이론적 모델과 부합하였다.

Influence of Dry Roasting of Whole Faba Beans (Vicia faba) on Rumen Degradation Characteristics in Dairy Cows, II: Starch

  • Yu, P.;Egan, A.R.;Holmes, J.H.G.;Leury, B.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제11권5호
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    • pp.503-509
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    • 1998
  • Whole faba beans (WFB) were dry roasted at different temperatures of 110, 130 and $150^{\circ}C$ for 15, 30 and 45 minutes (min) to determine the optimal heating conditions to increase bypass starch as glucose source which may be a limiting nutrient in high producing dairy cattle. Ruminant degradation characteristics of starch (St) of WFB were determined using in sacco method in 6 dairy cows fed 60% hay and 40% concentrate. Measured characteristics of St were soluble (washable) fraction (S), potentially degradation fraction (D) and the rate of degradation (Kd) of the insoluble but degradable St fraction. Based on measurement of these characteristics, percentage bypass starch (%BSt) and bypass starch (BSt) were calculated. Degradability of starch in the rumen was reduced by dry roasting at temperature of 130 and $150^{\circ}C$ and increased at $110^{\circ}C$. S varied from 50.0% in the raw whole faba beans (RWFB) and 53.7% in $110^{\circ}C$/15 min to 18.2% in $150^{\circ}C$/45 min. D varied from 49.9% in RWFB and 46.3% in $110^{\circ}C$/15 min to 81.8 % in $150^{\circ}C$/45 min. Kd varied from 9.8% in RWFB and 11.0% in the $110^{\circ}C$/30 min to 4.2 in $150^{\circ}C$/45 min. All these effects resulted in increasing %BSt from 22.1% in the $110^{\circ}C$/45 min and 23.9% in RWFB to 49.9% in the $150^{\circ}C$/45 min. Therefore BSt increased from 91.4 g/kg and 98.4 g/kg to 199.9 g/kg respectively. Dry roasting at $110^{\circ}C$ increased the starch rumen degradation. Treatment at higher temperature (130 and $150^{\circ}C$) decreased rumen degradation of starch and seemed to be linear up to highest values tested. No optimal dry roasting conditions of treatment could be determined at this stage. It may be concluded that dry roasting at temperatures of 130 and $150^{\circ}C$ was effective in shifting starch degradation from rumen to intestine to increase bypass starch.

Liquid Chromatography Quadrupole Time-Of-Flight Tandem Mass Spectrometry for Selective Determination of Usnic Acid and Application in Pharmacokinetic Study

  • Fang, Minfeng;Wang, Hui;Wu, Yang;Wang, Qilin;Zhao, Xinfeng;Zheng, Xiaohui;Wang, Shixiang;Zhao, Guifang
    • Bulletin of the Korean Chemical Society
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    • 제34권6호
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    • pp.1684-1688
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    • 2013
  • A rapid and sensitive method for determining usnic acid of Lethariella cladonioides in rat was established using high performance liquid chromatography (HPLC) quadrupole time-of-flight (QTOF) tandem mass (MS/MS). Rat plasma was pretreated by mixture of acetonitrile and chloroform to precipitate plasma proteins. Chromatographic separation was achieved on a column ($50{\times}2.1$ mm, $5{\mu}m$) with a mobile phase consisting of water (containing $5{\times}10^{-3}$ M ammonium formate, pH was adjusted to 3.0 with formic acid) and acetonitrile (20:80, v/v) at a flow rate of 0.3 mL/min. A tandem mass spectrometric detection with an electrospray ionization (ESI) interface was conducted via collision induced dissociation (CID) under negative ionization mode. The MS/MS transitions monitored were m/z 343.0448 ${\rightarrow}$ m/z 313.2017 for usnic acid and m/z 153.1024 ${\rightarrow}$ m/z 136.2136 for protocatechuic acid (internal standard). The linear range was calculated to be 2.0-160.0 ng/mL with a detection limit of 3.0 pg/mL. The inter- and intra-day accuracy and precision were within ${\pm}7.0%$. Pharmacokinetic study showed that the apartment of usnic acid in vivo confirmed to be a two compartment open model. The method was fully valid and will probably be an alternative for pharmacokinetic study of usnic acid.

지리오갈피 발효주의 숙성 중 품질변화 (Developing the Quality of Traditional Fermented Liquor Using Acanthopanax chiisanensis)

  • 김명석;조수정;이상원
    • 생명과학회지
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    • 제30권1호
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    • pp.70-76
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    • 2020
  • 지리오갈피(Acanthopanax chilsanensis)를 이용한 지역 특산품 개발 및 소비촉진을 목적으로 지리오갈피 발효주를 개발하여 5~10℃, 60일 동안 숙성시키면서 발효숙성주의 품질특성 등을 검토하였다. 숙성 기간 동안 발효숙성주 중의 환원당 함량은 약간 감소하였으나 총산의 함량은 아주 완만하게 증가하였다. 지리오갈피 뿌리, 줄기 및 열매로 제조한 발효숙성주 중의 유기산 함량은 3종류의 숙성주 모두 lactic acid, formic acid, malic acid, tartaric acid 및 acetic acid의 순으로 그 농도가 높게 검출되었다. 그리고 유리당은 3 종류의 숙성주 모두 sucrose, glucose 및 mannose 등의 유리당이 검출되었으며 이들 중 glucose 함량이 모든 시험구에서 가장 높게 나타났다. Acanthoside-D 함량은 줄기 첨가 발효숙성주에서 64.12 ppm으로 가장 높게 나타났으며 발효주와 발효숙성주의 acanthoside-D 함량을 비교해 보면 발효숙성주에서 약간 높아지기는 했으나 거의 변화가 없는 것으로 나타났다. 발효숙성주 중의 총 유리아미노산 함량은 뿌리, 줄기 및 열매의 발효숙성주에서 각각 1,858.9, 2,855.1 및 2,672.2 mg/l로 나타났다. 숙성주의 색도를 검토한 결과 뿌리와 줄기를 첨가한 숙성주에서는 거의 유사한 L, a, b값을 나타내어 발효숙성주의 색깔도 비슷하게 나타났으나, 열매를 첨가한 숙성주에서는 L값이 낮고, a값이 높아 붉은 색을 많이 띄었다.

울산 울주지역 소규모 수도시설 지하수의 수리지화학적 특성 연구 (Hydrogeochemical Characteristics of Groundwater in the Small Waterworks at Ulju Region, Ulsan)

  • 김동수;김문수;조성진;김익현;이헌민;황종연;박선화;조훈제;김태승;김현구
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제22권5호
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    • pp.71-81
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    • 2017
  • The hydrogeochemical characteristics of groundwater in the small waterworks are examined with 81 groundwater samples in Ulju region, Ulsan. The pH ranged in 6.3-8.2 and did not exceed the drinking water standards. Electrical conductivity ranged from $50{\mu}S/cm$ to $1,719{\mu}S/cm$. It indicated that the electrical conductivities in groundwaters at the study area are relatively low, compared with other groundwaters in Ulsan area. The calcium concentrations in groundwaters ranged from 3.55 to 113.01 mg/L, and sodium concentrations ranged from 2.02 to 65.50 mg/L. Nitrate concentrations ranged from 0 to 100.56 mg/L and potassium concentrations ranged from N.D (not detected) to 2.50 mg/L. Major cations and anions were mainly derived from the water-rock interaction involving feldspar, gypsum and calcite. The groundwaters were mainly the $Ca-(Na)-HCO_3$ type, classified as the early stage of groundwater evolutions. The correlation between electrical conductivities and Ca concentrations in groundwaters was relatively high ($R^2=0.74$). In the correlations between ions, the correlation coefficient between $SO_4$ and Ca was 0.65 and between Mg and $HCO_3$ was 0.65.

CaO원 활성슬러지를 혼입한 시멘트 경화체 및 모르타르의 특성 (Characteristics of Cement Matrix/Mortar with CaO-based Activated-sludge)

  • 이용수;유성룡;신광호;추용식;김영엽
    • 콘크리트학회논문집
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    • 제29권4호
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    • pp.399-406
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    • 2017
  • CaO원 산업부산물은 CaO, $SO_3$$Al_2O_3$ 등으로 구성되어 있어 CaO 화합물의 원료로 사용되고 있다. 이러한 CaO원 산업부산물을 레미콘 회수수에 적용할 경우 슬러지수의 pH를 높여주어 콘크리트 분말원료의 수화 반응을 촉진 하여 콘크리트 조직을 치밀하게 하여 성능향상이 가능할 것이다. 본 연구에서는 레미콘 회수수에 CaO원 산업부산물 중 하나인 탈황석고를 혼입하여 제조된 활성슬러지의 효과를 확인하기 위하여 시멘트 경화체 및 모르타르의 특성을 분석하였다. 그 결과 시멘트 경화체의 경우 응결시간 단축 및 높은 안정성을 나타내었으며, 기기분석을 통해 수화반응이 촉진되었음을 확인할 수 있었다. 또한 활성 슬러지 제조를 위하여 CaO원으로서 사용된 탈황석고는 단위수량을 조절할 경우 작업성을 확보할 수 있을 뿐만 아니라 적절하게 혼입 될 경우 시멘트 사용량이 줄더라도 높은 강도 발현을 나타내는 것을 확인할 수 있었다.