• Title/Summary/Keyword: Isotope

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Radio-isotope Red Cell Survival Studies Recommended by ICSH (방사성동위원소(放射性同位元素)를 이용(利用)한 적혈구수명측정법(赤血球壽命測定法)(ICSH추천(推薦)))

  • The Korea Society of Nuclear Medicine The Korea Society of Nuclear Medicine
    • The Korean Journal of Nuclear Medicine
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    • v.5 no.1
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    • pp.1-10
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    • 1971
  • 혈액질환(血液疾患), 특히 용혈성빈혈(溶血性貧血)을 수반(隨伴)한 경우(境遇)에 적혈구(赤血球)의 생성(生成) 및 파괴과정(破壞過程)을 정확(正確)히 파악(把握)하는 것은 중요(重要)하여 특히 적혈구수명측정(赤血球壽命測定)은 빈혈(貧血)의 본능(本能) 및 발생기전(發生機轉)을 이해(理解)하는데는 물론 병인적(病因的) 치료(治療) 및 예후(豫後)를 결정(決定)하는데 대단(犬端)히 유용(有用)하다. 적혈구수명측정(赤血球壽命測定)에는 1919년(年) Ashby가 개발(開發)한 differential agglutination법(法)이 이용(利用)되어 왔으나 수혈(輸血)에 따른 위험(危險)이 있고 방법(方法)이 복잡(複雜)하다는 단점(短點)을 가져 새로운 적혈구수명측정법(赤血球壽命測定法)이 연구(硏究)되어 왔다. 최근(最近)에 $^{51}Cr$이나, $^{32}DFP$같은 방사성동위원소(放射性同位元素)를 이용(利用)한 방법(方法)이 도입(導入)된 이래(以來) 임상적(臨床的)으로 적혈구수명측정(赤血球壽命測定)이 많이 시행(施行)되고 있지만 아직까지도 그 방법(方法)이나 결과(結果)의 해석(解釋)에 표준화(標準化)가 안되어 있다. 현재(現在) 임상영역(臨床領域)에서 가장 널리 이용(利用)되고 있는 적혈구수명측정법(赤血球壽命測定法)은 방사성(放射性) chromium($^{51}Cr$)법(法)으로 1950년(年) Gray와 Sterling에 의(依)해 창안(創案)된 이래(以來) 많은 학자(學者)들에 의(依)해 여러 가지 변법(變法)이 고안(考案)되어 왔는데, 이의 가장 큰 이유(理由)는 $^{51}Cr$이 적혈구표지(赤血球標識)에 가장 이상적(理想的)인 것만은 아니고 그 결과(結果)에 많은 요인(要因)들이 영향(影響)을 미치기 때문이다. 또 이런 변법(變法)의 사용(使用)은 각(各) 검사(檢査)에서 계산(計算)된 측정치(測定値)에 차이(差異)가 있어 그 결과(結果)의 해석(解釋) 및 비교(比較) 검토(檢討)에 적지않은 난점(難點)이 생겨 표준화(標準化)된 공통적(共通的)인 방법(方法)의 사용(使用)이 중요(重要)하다는 사실(事實)이 인식(認識)되게 되었다. 1966년(年) 호주(濠洲)의 Sydney에서 개최(開催)되었든 제11차(第11次) 국제혈액학회(國際血學會)때 열린 제4차(第4次) International Committee for Standardization in Haematology(ICSH)에서 Diagnostic Applications of Radioisotopes in Haematology에 관(關)한 expert panel을 갖을것을 의결(議決)하여 다음과 같은 12명(名)의 위원(委員)이 결정(決定)되었으며 위원회(委員會)의 의장(議長)에 Dr. Szur, 총무(總務)에 Dr. Glass가 각각(各各) 선임(選任)되었다. 그간(間) 1967년(年) 영경(英京) London에서 첫 회합(會合)이 있은후(後) New York, Vienna(IAEA후원(後援)) Brthesda(NIH후원(後援))에서 전문위원회(專門委員會)를 갖고 적혈구수명측정법(赤血球壽命測定法)에 관(關)한 의견(意見)의 일치(一致)를 보았다. ICSH와 국제혈액학회(國際血學會)에서는 이번에 결정(決定)된 적혈구수명측정법(赤血球壽命測定法)을 널리 소개(紹介)하며, 측정법(測定法)과 얻어진 결과(結果)의 해석(解釋)에 표준화(標準化)를 기(期)할 목적(目的)으로 이에 연관성(聯關性)있는 전문지(專門誌)에 게재(揭載)할 것을 요청(要請) 받었기에 이에 전문(全文)을 소개(紹介)하는 바이다. 이들은 방사성(放射性) chromium 법(法)의 모든 세부적(細部的)인 면(面)을 표준화(標準化)하고 있으며 그간(間) 가장 논란(論難)의 대상(對象)이 되었던, $^{51}Cr$-표지방법(標識方法)에 있어서의 세가지 변법(變法), 즉 ACD법(法), Citrate-wash법(法), ACD/ascorbic acid법(法)을 모두 인정(認定)하고 있다. 또한, DFP($DF^{32}P$ 또는 $^3H-DFP$) 표지법(標識法)의 표준방법(標準方法)도 기술(記述)하고 있으며, 더욱 중요(重要)한 것은 적혈구수명측정법(赤血球壽命測定法)으로서 현재(現在)까지 대부분(大部分)의 학자(學者)가 사용(使用)하여 왔던 지표(指標)인 $T_{50}Cr$ 대신(代身)에 mean red cell life span을 사용(使用)할 것을 권(勸)하고 있다.

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Factors Related to the Resolution of Primary Vesicoureteral Reflux (요로감염 영아에서 일차성 방광요관역류)

  • Jung, Jae-Won;Woo, Mi-Kyoung;Koo, Ja-Wook
    • Childhood Kidney Diseases
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    • v.13 no.1
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    • pp.40-48
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    • 2009
  • Purpose : This study was performed to identify factors related to the resolution of primary vesicoureteral reflux (VUR) in infants. Methods : We reviewed 183 infants (M : F=149 : 34) diagnosed as urinary tract infection (UTI) between February 2002 and July 2007 at Sanggye Paik Hospital. The diagnosis of UTI was made by culture from a urine specimen obtained by suprapubic puncture (n=97), catheterization (n=83), or collection bag method (n=3, twice positive culture of same organism). All of the infants were performed renal ultrasonography, DMSA scan and voiding cystourethrography (VCUG) study. Follow-up imaging consisted of contrast VCUG or direct isotope VCUG at interval of 1 year. We evaluated the relationship of clinical and laboratory finding, radiologic finding in infants with VUR. Results : Among 51 VUR patients, 18 infants had grade I-II, 12 infants had grade III and the other 21 patients had grade IV-V. Abnormal findings including hydronephrosis on renal ultrasonography were not correlated with severity of VUR. However, the incidence of renal defect in the first DMSA scan showed a tendency of direct correlation with severity of VUR in female patients only (P<0.001). There was significant difference of resolution rate in three VUR groups (grade I-II, III, IV-V) in male patients only (P=0.025). Resolution rate was higher for male patients with unilateral VUR than bilateral (P<0.001). But unilaterality had not any affect on VUR resolution in female VUR patients (P=0.786). Resolution rate was higher for VUR patients without renal scar than VUR patients with renal scar (P<0.001). Conclusion : According to our findings, grade of VUR, laterality and renal scar are the factors that contribute to resolution of primary VUR in male and female infants differently.

Geochemical Characteristics of the Hydrocarbons from the Block 6-1, Ulleung Basin (울릉 분지 6-1 광구에서 발견된 탄화수소의 지화학적 특성)

  • Lee, Young-Joo;Cheong, Tae-Jin;Oh, Jae-Ho;Park, Se-Jin;Yi, Song-Suk
    • The Korean Journal of Petroleum Geology
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    • v.11 no.1 s.12
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    • pp.1-8
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    • 2005
  • Seventeen exploratory wells have been drilled in the Block VI-1 of offshore Korea, which is located in the southern part or the Ulleung Basin. Gas show has been recognized from most of the wells, and gas and condensate have been accompanied in some wells. Commercial discovery of gas, accompanied by condensate, has been made from Gorae V well. The reservoir gases or the Dolgorae III, Gorae I, and Gorae V wells in the Ulleung Basin mainly consists of hydrocarbon gases (>93%). These gases are thermogenic wet gases which contain more than 96% of the methane and result from the cracking of petroleum or kerogen. Based on the chemistry and composition of the gases and stable isotope data, they seem to be generated from different source rocks. The condensates from the Gorae I and V wells are mostly generated from terrestrial organic matter. Lacustrine organic matter may not play an important role for the generation of these condensates. The condensates from the Gorae V wells consist predominantly of terrestrial organic matter but with minor subsidiary input from marine organic matter. The condensates from Gorse I and V wells may be generated from different source rocks. The thermal maturity level of the condensates from the Gorae V well ranges from early to middle oil generation zone and condensate from Gorae I reaches middle oil window. Correlation or the thermal maturation level of the condensates and organic matter in the sediments reveals that a depth of the generation of liquid hydrocarbons can be inferred to 3,000 m and 3,900 m for the Gorae V and I wells, respectively. Gorae V well, however, did not reach the target depth and the geochemical data of the Gorae I well were obscured due to the severe sediment caving in.

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The Usefulness of Scintigraphy for the Detection of Gastroesophageal Reflux and Pulmonary Aspiration (위식도 역류와 폐 흡인 진단 방법으로서 위식도 역류 신티그래피의 유용성)

  • Kang, Sung-Kil;Hyun, In-Young;Lim, Dae-Hyun;Kim, Jeong-Hee;Son, Byong-Kwan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.11 no.1
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    • pp.12-20
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    • 2008
  • Purpose: Chronic pulmonary disease may be caused by aspiration of gastric contents secondary to gastroesophageal reflux. At present, there is no gold standard for documenting pulmonary aspiration. The purpose of this study was to investigate the usefulness of radionuclide scintigraphy in the detection of gastroesophageal reflux and pulmonary aspiration. Methods: Thirty-five patients with suspected aspiration pneumonia, and five normal control subjects, were included in the study. All subjects underwent gastroesophageal reflux scintigraphy after the ingestion of a $^{99m}Tc$-tin colloid mixture. Dynamic images to detect gastroesophageal reflux were obtained for 1 hour. Additional static images of the chest, to detect lung aspiration, were obtained at 6 and 24 hours after oral ingestion of the tin colloid. In addition to visual analysis, pulmonary aspiration was quantitated by counting the number of pixels labeled with radioactive isotope in the region of interest (ROI) of both lung fields. Aspiration index (AI) was obtained by subtracting the pixel counts of the background from the pixel counts of the ROI. Results: Among 35 patients with suspected aspiration pneumonia, 23 proved to have gastroesophageal reflux by scintigraphy. One patient showed definite pulmonary accumulation of activity by visual analysis of the 6-hour image. Thirty of 35 (85.7%) patients showed higher AI beyond the upper limit of AI in the healthy controls. When we compared the reflux group with the non-reflux group, there was a significantly higher AI at 6 hours in the reflux group (p<0.05). Conclusion: The results suggest that radionuclide scintigraphy is useful in detecting small pulmonary aspiration in patients with suspected aspiration pneumonia secondary to reflux.

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Hydrogeochemistry of Some Abandoned Metal Mine Creeks in the Hwanggangri Mining District, Korea : A Preliminary Study (황강리 광화대에 분포하는 일부 폐금속 광산수계의 수리지구화학적 특성 : 예비연구)

  • 이현구;이찬희;이종창
    • Journal of the Korean Society of Groundwater Environment
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    • v.6 no.4
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    • pp.194-205
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    • 1999
  • Hydrogeochemical variation and environmental isotope at the some abandoned metal mine (Sanggok, Keumsil, Jangpung and Samdeok) creeks of the Hwanggangri mining district were carried out based upon the physicochemical properties for surface water collected of February in 1998. Hydrogeochemical composition of the all water samples are characterized by the relatively significant enrichment of Ca$^{2}$, alkaline ions, N $O_3$$^{-}$ and Cl$^{-}$ in normal surface water, whereas the surface waters near the mining area are relatively enriched in Ca$^{2+$, Mg$^{2+}$, heavy metals. HC $O_3$$^{-}$ and S $O_4$$^{2-}$. Surface waters of the mining creek have low pH, high EC and extremely high concentrations of TDS compared with surface water of the non-mining creeks. The range of $\delta$D and $\delta$$^{18}$O values (SMOW) in the waters are shown in -65.0 to-71.2$\textperthousand$ and -9.1 to-10.2$\textperthousand$. The d($\delta$D-$\delta$$^{18}$O) value with those of water samples ranged from 7.3 to 10.9. These $\delta$D and $\delta$$^{18/}$ of the acid mine water are more heavy values than those of surface water. The values have revealed the positive correlation between isotopic compositions and major elements, because those $\delta$D and $\delta$$^{18}$O values increase with increasing TDS. HC $O_3$$^{-}$ , S $O_4$$^{2-}$ and Ca$^{2+}$ concentration. Using WATEQ4F, saturation index of albite calcite, dolomite and mostly clay minerals in water of the mining area show undersaturated and progressively evolved toward the equilibrium condition due to fresh water mixing, however, surface waters of the non-mining area are nearly saturated and/or supersaturated. Geochemical modeling showed that mostly toxic heavy metals within water in the mining creek may exist largely in the from of metal-sulfate (MS $O_4$$^{2-}$), free metal (M$^{2+}$/), C $O_3$$^{-}$ and/or OH$^{-}$ complex ions. Based on the geology, water chemistry and environmental istopic data the water compositions from the Sanggok and Keumsil mine creek (consist mainly of Cambro-Ordovician carbonate rocks of the Cho-seon Supergroup) show higher PH, Ca$^{2+}$, Mg$^{2+}$ , HC $O_3$$^{-}$ and more heavy $\delta$D and $\delta$$^{18}$O values than those from the Jangpung and Samdeok mine creek (consist of age -unknown metasedimentary rocks of the Ogcheon Supergroup and/or Jurassic grani-toids), but each of these waters represents a similar hydrogeochemical evolution path by the mine water mixing.

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Geochemical Studies of Geothermal Waters in Yusung Geotheraml Area (유성 지역 지열수의 지구화학적 특성 연구)

  • 김건영;고용권;김천수;배대석;박맹언
    • Journal of the Korean Society of Groundwater Environment
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    • v.7 no.1
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    • pp.32-46
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    • 2000
  • Hydrogeochemical and isotope ($\delta$$^{18}$ O, $\delta$D, $^3$H, $\delta$$^{13}$ C, $\delta$$^{34}$ S, $^{87}$ Sr/$^{86}$ Sr) studies of various kinds of waters (thermal groundwater, deep groundwater, shallow groundwater, and surface water) from the Yusung area were carried out in order to elucidate their geochemical characteristics such as distribution and behaviour of major/minor elements, geochemical evolution, reservoir temperature, and water-rock interaction of the thermal groundwater. Thermal groundwater of the Yusung area is formed by heating at depth during deep circlulation of groundwater and is evolved into Na-HCO$_3$type water by hydrolysis of silicate minerals with calcite precipitation and mixing of shallow groundwater. High NO$_3$contents of many thermal and deep groundwater samples indicate that the thermal or deep groundwaters were mixed with contaminated shallow groundwater and/or surface water. $\delta$$^{18}$ O and $\delta$D are plotted around the global meteoric water line and there are no differences between the various types of water. Tritium contents of shallow groundwater, deep groundwater and thermal groundwater are quite different, but show that the thermal groundwater was mixed with surface water and/or shallow groundwater during uprising to surface after being heated at depths. $\delta$$^{13}$ C values of all water samples are very low (average -16.3$\textperthousand$%o). Such low $\delta$$^{13}$ C values indicate that the source of carbon is organic material and all waters from the Yusung area were affected by $CO_2$ gas originated from near surface environment. $\delta$$^{34}$ S values show mixing properties of thermal groundwater and shallow groundwater. Based on $^{87}$ Sr/$^{86}$ Sr values, Ca is thought to be originated from the dissolution of plagioclase. Reservoir temperature at depth is estimated to be 100~1$25^{\circ}C$ by calculation of equilibrium method of multiphase system. Therefore, the thermal groundwaters from the Yusung area were formed by heating at depths and evolved by water-rock interaction and mixing with shallow groundwater.

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Genetic Environments of Hydrothermal Vein Deposits in the Pacitan District, East Java, Indonesia (인도네시아 동부자바 빠찌딴(Pacitan) 광화대 열수 맥상 광상의 성인 연구)

  • Choi, Seon-Gyu;So, Chil-Sup;Choi, Sang-Hoon;Han, Jin-Kyun
    • Economic and Environmental Geology
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    • v.28 no.2
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    • pp.109-121
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    • 1995
  • The hydrothermal vein type deposits which comprise the Kasihan, Jompong and Gempol mineralized areas are primarily copper and zinc deposits, but they are also associated with lead and/or gold mineralization. The deposits occur within the Tertiary sedimentary and volcanic rocks in the Southern Mountain zone of the eastern Java island, Indonesia. Mineralization can be separated into two or three distinct stages (pre-and/or post- ore mineralization stages and main ore mineralization stage) which took place mainly along pre-existing fault breccia zones. The main phase of mineralization (the main ore stage) can be usually classified into three substages (early, middle and late) according to ore mineral assemblages, paragenesis, textures and their chemical compositions. Ore mineralogy and paragenesis of the three areas in the district are different from each other. Pyrite, pyrrhotite (/arsenopyrite), iron-rich (up to 20.5 mole % FeS) sphalerite and (Cu-)Pb-Bi sulfosalts are characteristic of the deposits in the Kasihan (/Jompong) area. On the other hand, pyrite + hematite + magnetite + iron-poor (2.7 to 3.6 mole % FeS) sphalerite assemblage is restricted to the Gempol area. Fluid inclusion data suggest that fluids of the main ore stage evolved from initial high temperatures (near $350^{\circ}C$) to later lower temperatures (near $200^{\circ}C$) with salinities ranging from 0.8 to 10.1 equiv. wt. percent NaCl. Each area represents a separate hydrothermal system: the mineralization at Kasihan and Jompong were largely due to early fluid boiling coupled with later cooling and dilution, whereas the mineralization at Gempol was mainly resulted from cooling and dilution by an influx of cooler meteoric waters. Fluid inclusion evidence of boiling indicates that pressures of ${\geq}95$ to 255 bars (${\geq}95$ bars for the Gempol area: $\approx$ 120 to 170 bars for the Jompong area: $\approx$ 140 to 255 bars for the Kasihan area) during portions of main ore stage mineralization. Equilibrium thermodynamic interpretation indicates that the evolution trends of the temperature versus fS2 variation of ore stage fluids in the Pacitan district follow two fashions: ore fluids at Kasihan and Jompong changed from the pyrite-pyrrhotite sulfidation stage towards pyritehematite- magnetite state, whereas those at Gempol evolved nearly along pyrite-hematite-magnetite reaction curve with decreasing temperature. The sulfur isotope compositions of sulfide minerals are consistent with an igneous source of sulfur with a ${\delta}^{34}S_{{\Sigma}s}$ value of about 3.3 per mil. The oxygen and hydrogen isotopic compositions of the fluids in each area indicate a progressive shift from the dominance of highly exchanged meteoric water at early hydrothermal systems towards an un- or less-exchanged meteoric water at later hydrothermal systems.

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Origin and Hydrochemical Characteristics of Natural Carbonated Water at Seoqwipo, Jeju Island (제주도 서귀포지역 천연탄산수의 기원과 수리화학특성)

  • Jeong, Chan Ho;Lee, Yong Cheon;Lee, Yu Jin;Choi, Hyeon Young;Koh, Gi Won;Moon, Duk Chul;Jung, Cha Youn;Jo, Si Beom
    • The Journal of Engineering Geology
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    • v.26 no.4
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    • pp.515-529
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    • 2016
  • In this study, geochemical composition, CFCs (Chlorofluorocarbons), ${\delta}^{18}O$, ${\delta}D$, ${\delta}^{13}C$ isotopes and noble gases isotopes (He, Ne) were analyzed to determine their recharge age, source of $CO_2$ gas and noble gases of carbonated hot spring water and carbonated-water samples collected in the Seoqwipo of the Jeju. The pH of the carbonated waters ranges from 6.21 to 6.84, and the high electrical conductivity range ($1,928{\sim}4,720{\mu}S/cm$). Their chemical composition is classified as $Mg(Ca,\;Na)-HCO_3$ and $Na(Ca,\;Mg)-HCO_3$ types. As a result of the calculation of groundwater age using CFCs concentrations as an environmental tracer, the carbonated water and groundwater were estimated to be about 47.5~57.2 years and about 30.3~49.5 years, respectively. The ${\delta}^{13}C$ values of carbonated water range from -1.77 to -7.27‰, and are plotted on thr deep-seated field or the mixing field of the deep-seated and inorganic origin. Noble gases isotopic ($^3He/^4He$, $^4He/^{20}Ne$) ratio shows that helium gas of carbonated hot waters comes from deep-seated magma origin.

Establishment of an Ice Core Processing Method and Analytical Procedures for Fundamental Proxies (빙하코어의 전처리 방법 및 기초 프록시 분석법 확립)

  • Jun, Seong Joon;Hong, Sang Bum;Hur, Soon Do;Lee, Jeonghoon;Kang, Jung-Ho;Hwang, Hee Jin;Chung, Ji Woong;Jung, Hye Jin;Han, Changhee;Hong, Sungmin
    • Ocean and Polar Research
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    • v.36 no.1
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    • pp.13-24
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    • 2014
  • We established the first complete ice core processing method and analytical procedures for fundamental proxies, using a 40.2 m long ice core drilled on the Mt. Tsambagarav glacier in the Mongolian Altai mountains in July 2008. The whole core was first divided into two sub ice core sections and the measurements of the visual stratigraphy and electrical conductivity were performed on the surface of these sub core sections. A continuous sequence of samples was then prepared for chemical analyses (stable isotope ratios of oxygen ($^{18}O/^{16}O$) and hydrogen ($^2H/^1H$), soluble ions and trace elements). A total of 29 insoluble dust layers were identified from the measurement of visual stratigraphy. The electrical conductivity measurement (ECM) shows 11 peaks with the current more than 0.8 ${\mu}A$ Comparing the profiles of $SO_4{^{2-}}$ and $Cl^-$ concentrations to correlate with known volcanic eruptions, the first two ECM peaks appear to be linked to the eruptions (January and June 2007) of Kliuchevskoi volcano on the Kamchatka Peninsula of Russia, which supports the reliability of our ECM data. Finally, the composition of stable isotopes (${\delta}^{18}O$ and ${\delta}D$) shows a well-defined seasonal variation, suggesting that various chemical proxies may have been well preserved in the successive ice layers of Tsambagarav ice core. Our ice core processing method and analytical procedures for fundamental proxies are expected to be used for paleoclimate and paleoenvironmental studies from polar and alpine ice cores.

Regeneration Processes of Nutrients in the Polar Front Area of the last Sea IV. Chlorophyll a Distribution, New Production and the Vertical Diffusion of Nitrate (동해 극전선역의 영양염류 순환과정 IV. Clorophyll a 분포, 신생산 및 질산염의 수직확산)

  • MOON Chang-Ho;YANG Sung-Ryull;YANG Han-Soeb;CHO Hyun-Jin;LEE Seung-Yong;KIM Seok-Yun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.2
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    • pp.259-266
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    • 1998
  • A study on the biological and chemical characteristics in the middle last Sea of Korea was carried out at 31 stations in October $11\~18$, 1995 on board the R/V Tam-Yang. The chlorophyll a concentration, new and regenerated production, and the vertical diffusion of nitrate from the thermocline structure were investigated. From the vertical distribution of chlorophyll a, subsurface maxima were observed near the thermorline at most stations including the frontal zone, except at the southern stations where the maximum chloropyll a concentration occurred at the surface, The nanophytoplankton was the most dominant fraction comprising $83.5\%$ of total phytoplankton cell numbers, but netphytoplankton were common at the southern stations where the dominant species were Rhizosolenia sp. Nitrogenous new production and regenerated productions were measured using the stable isotope $^{15}N$ nitrate and ammonia uptake method. The vertically integrated nitrogen production varied between 8.470 and $72.945\;mg\;N\;m^{-2}\;d^{-1}$. The f-ratio, which is the traction of new production from primary production, waried between 0.03 and 0.72, indicating that $3\%$ to $72\%$ of primary production was supported by the input of nutrients from below the euphotic zone and the rest are supported by ammonia recycled within the euphotic layer. This range of f-ratio encompasses from extremely oligotrophic to eutrophic area characteristics. The differences in productivity and f-ratio among stations were related to frontal structure and the bottom topography. The values were high near the frontal zone and low outside of it, and the station near Ulleng Island showed the highest f-ratio. Vertical diffusion coefficients were calculated from both the water column stability (Kz-1) of King and Devol's equation (1979) and new nitrogen requirement (Kz-2). The values of Kz-2 ($0.11\~0.55\;cm^2/s$) were relatively low compared to the values reported previously.

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