• 제목/요약/키워드: HG

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MBE법으로 성장된 CdTe(211)/Si 기판을 이용한 MOVPE HgCdTe 박막의 특성 향상 (Improvement of HgCdTe Qualities grown by MOVPE using MBE grown CdTe/Si as Substrate)

  • 김진상;서상희
    • 센서학회지
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    • 제12권6호
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    • pp.282-288
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    • 2003
  • MBE 방법으로 Si 기판위에 성장된 CdTe(211) 박막위에 MOVPE 법으로 HgCdTe 박막을 성장하였다. 성장된 박막의 표면은 hillock 등의 결함이 없는 매우 균일한 형상을 보였다. HgCdTe 박막표면의 EPD(etch pit density) 및 (422) 결정면의 이중 결정 x-선 회절 피크의 반치폭으로 본 결정성은 GaAs 기판위에 성장된 HgCdTe 박막에 비하여 우수하였다. GaAs 기판 위에 MOVPE 법으로 성장된 HgCdTe는 기판처리 과정에서 유입된 p-형 불순물로 인해 p-형 전도성을 나타내었으나 (211)CdTe 기판 위에 성장된 박막은 77K에서 $8{\times}10^{14}/cm^3$의 운반자 농도를 갖는 n-형 전도성을 보였다. 본 연구의 결과는 최근 요구되고 있는 $1024{\times}1024$급 이상의 화소를 갖는 대면적 HgCdTe 적외선 소자 제작에 널리 적용될 것으로 판단된다.

한국산 수산물의 총 수은 및 메틸수은 농도 및 위해도 평가 (Concentrations and Risk Assessment of Total Mercury and Methyl Mercury in Commercial Marine Fisheries from Korea)

  • 최민규;윤세라;박혜정;이자연;이인석;황동운;윤민철;최우석
    • 한국수산과학회지
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    • 제50권6호
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    • pp.675-683
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    • 2017
  • Total mercury (T-Hg) and methyl mercury (MeHg) were determined in marine fisheries (41 species, n=87) commonly consumed in Korea, using a gold amalgamation method and gas chromatography-cold vapor atomic fluorescent spectroscopy, respectively. Concentrations of T-Hg and MeHg in all samples (31 fish, 4 crustaceans, 4 cephalopods, and 2 gastropod species) were in the range of 0.016-0.495 (mean, 0.093) mg/kg-wet and not detected-0.338 (mean, 0.067) mg/kg-wet, respectively. The concentrations of MeHg in marine fisheries were significantly correlated with T-Hg concentrations (P<0.001). The highest mean concentrations of T-Hg and MeHg were found in fish species, followed by crustaceans. The contribution of MeHg to T-Hg was in the range of 64-95% (mean, 83%) in cephalopods, 28-98% (mean, 69%) in fish, and 26-88% (mean, 57%) in crustaceans. The weekly intakes of T-Hg and MeHg by fisheries consumption for the Korean general population were estimated to be 0.463 and $0.338{\mu}g/kg$ body weight/week, respectively. The concentrations and intakes of T-Hg and MeHg were less than the allowable residue levels and in the range of 12 to 17% of the provisional tolerable weekly intake (PTWI) applied in Korea.

國內詞育 원숭이의 血液가스値에 관한 硏究 (Studies on Blood Gas Values in Non-Human Primates Reared in Korea)

  • 윤상보;김덕환;서지민;신남식;현병화;박배근;송희종
    • 한국임상수의학회지
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    • 제18권4호
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    • pp.397-401
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    • 2001
  • Blood gas values such as pO$_2$ were studied in common marmosets, crab-eating macaques and Japanese macaques, rhesus macaques and celebes macaque reared in Korea. Blood pH and blood gas values were evaluated in both arterial and venous blood. pH, p$CO_2$, and pO$_2$, of arterial blood in common marmosets were measured as 7.4$\pm$0.1, 29.2$\pm$3.6 mmHg and 81.5$\pm$8.9 mmHg, respectively. Corresponding values in one crab-eating macaque were 7.3, 41.3 mmHg and 46.5 mmHg, respectively. In case of venous blood, pH, p$CO_2$, and pO$_2$, in common marmosets were observed as 7.2$\pm$0.2, 64.9$\pm$18.3 mmHg and 23.5$\pm$5.4 mmHg, respectively. On the while, pH, p$CO_2$, and pO$_2$, of venous blood in crab-eating macaques showed 7.2$\pm$0.2, 49.9$\pm$8.0 mmHg and 38.3$\pm$8.8 mmHg, respectively. Venous pH, p$CO_2$, and pO$_2$, in Japanese macaques were 7.1$\pm$0.2, 56.4$\pm$5.3 mmHg and 40.1$\pm$9.3 mmHg, respectively. Those values in one rhesus macaque were 7.2, 61.1 mmHg and 24.9 mmHg, and in celebes macaque were 7.1, 54.3 mmHg and 31.8 mmHg, respectively.

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일부 도시노인들의 고혈압증 유병률 (Prevalence of Hypertension Among the Aged in Urban Area)

  • 김석범;강복수;정종학
    • Journal of Yeungnam Medical Science
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    • 제4권1호
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    • pp.123-128
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    • 1987
  • 도시 노인들의 고혈압증의 빈도 및 분포를 파악하기 위하여 1986년 1월부터 동년 12월 사이에 대구시에 거주하는 노인 남자 565명, 여자 762명 총 1,327명에 대해 조사한 성적을 요약하면 다음과 같다. 수축기혈압의 평균치는 $134.2{\pm}24.78mmHg$로 남자 $136.0{\pm}25.01mmHg$, 여자 $133.0{\pm}24.56mmHg$였다. 이완기혈압의 평균치는 $83.0{\pm}14.43mmHg$로 남자 $83.7{\pm}14.41mmHg$, 여자 $82.4{\pm}14.43mmHg$였다. 세계보건기구의 기준에 따른 고혈압증 유병률에 있어 pure systolic hypertension (${\geq}160$/<95mmHg)인 자는 7.2%로 남자 7.8%, 여자 6.8%였다. Pure diastolic hypertension (<160/${\geq}95mmHg$)인 자는 4.8%로 남자 6.0%, 여자 3.9%였다. Both systolic and diastolic hypertension (${\geq}60/{\geq}95mmHg$)인 자는 12.9%로 남자 13.5%, 여자 12.9%였다. 합동위원회의 기준에 의하면 normal (/<90mmHg)인 자는 49.1%로 남자 46.7%, 여자 50.8%였다. Mild hypertension (/90-104mmHg)인 자는 34.6%로 남자 34.5%, 여자 34.6%였다. Moderate hypertension (/105-114mmHg)인 자는 3.6%로 남자 5.1%, 여자 2.5%였다. Severe hypertension ($/{\geq}115mmHg$)인 자는 2.7%로 남자 2.3%, 여자 3.0%였다. Boderline isolated systolic hypertension (140-159/<90mmHg)인 자는 7.6%로 남자 9.0%, 여자 6.6%였다. Isolated systolic hypertension (${\geq}160$/<90mmHg)인 자는 2.4%로 남자 2.3%, 여자 2.5%였다.

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열처리 조건에 따른 HgCdTe의 접합 특성 (HgCdTe Junction Characteristics after the Junction Annealing Process)

  • 정희찬;김관;이희철;김홍국;김재묵
    • 전자공학회논문지A
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    • 제32A권2호
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    • pp.89-95
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    • 1995
  • The structure of boron ion-implanted pn junctio in the vacancy-doped p-type HgCdTe was investigated with the differential Hall measurement. The as-implanted junction showed the electron concentration as high as 1${\times}10^{18}/cm^{3}$ and the junction depth of 0.6.mu.m. When the HgCdTe junction was heated in oven, the electron concentration near the junction decreased and the junction depth increased as the annealing temperature and time increased. The junction structure after the thermal annealing was n$^{+}$/n$^{-}$/p. For the 200.deg. C 20min annealed sample, the electron mobility was 10$^{4}cm^{2}/V{\cdot}$s near the surface(n$^{+}$), and was larger thatn 10$^{5}cm^{2}/V{\cdot}$s near the junction(n$^{+}$). The junction formation mechanism is conjectured as follows. When HgCdTe is ion-implanted, the ion energy generates crystal defecis and displaced Hg atoms HgCdTe is ion-implanted, the ion energy generates crystal defecis and displaced Hg atoms near the surface. The displaced Hg vacancies diffuse in easily by the thernal treatment and a fill the Hg vacancies in the p-HgCdTe substrate. With the Hg vacancies filled completely, the GfCdTe substrate becomes n-type because of the residual n-type impurity which was added during the wafer growing. Therefore, the n$^{+}$/n$^{-}$/p regions are formed by crystal defects, residual impurities, and Hg vacancies, respectively.

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Difference in Methylmercury Exposure to Fetus and Breast-feeding Offspring: A Mini-Review

  • Sakamoto Mineshi;Murata Katsuyuki;Nakai Kunihiko;Satoh Hiroshi
    • 한국환경보건학회지
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    • 제31권3호
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    • pp.179-186
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    • 2005
  • The purpose of this paper was to concisely review the practical changes in MeHg concentrations in fetus and offspring throughout gestation and suckling from our recent animal and human studies. In the animal study, adult female rats were given a diet containing 5ug/g Hg (as MeHg) for 8 weeks. Then they were mated and subsequently given the same diet throughout gestation and suckling. On embryonic days 18, 20, 22 and at parturition, the concentrations of Hg in the brains of fetus were approximately 1.5-2.0 times higher than those in the mothers. However, during the suckling period Hg concentrations in the brain rapidly declined to about 1/10 of that during late pregnancy. Hg concentrations in blood also decreased rapidly after birth. In human study, Hg concentrations in red blood cells (RBC-Hg) in 16 pairs of maternal and umbilical cord blood samples were compared at birth and 3 months of age after parturition. RBC-Hg in the umbilical cords was about 1.6 times higher than those in the mothers at parturition. However, all the infants showed declines in Hg concentrations throughout the breast-feeding period. RBC-Hg at 3 months of age was about half that at birth. Both the animal and human studies indicated that MeHg exposure to the fetus might be especially high but it dramatically decreases during the suckling period. Therefore, close attention should be paid to the gestation rather than the breast-feeding period to avoid the risk of MeHg to human infants.

대기 중 수은의 일주기 농도분포와 수멸작용의 관계에 대한 고찰 (Diurnal Variabilities of Atmospheric Mercury Distribution and Its Relationship with Sink Mechanism)

  • 김민영;김기현
    • 한국대기환경학회지
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    • 제16권1호
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    • pp.49-60
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    • 2000
  • The concentration of atmospheric mercury(Hg0 and relevent environmental parameters that include both meteorological and criteria pollutant data were dtermined at hourly intervals during two field campaigns covering the periods of September 1997 and May/June 1998. The mean concentrations of Hg for the two study periods were computed as 3.94 and 3.43ngm-3, respectively. Through a separation of these data into both daytime and nighttime periods, we further analyzed diurnal variation patterns for Hg between two different seasons. Using our Hg data sets, we were able to recognize two contrasting diurnal variation patterns of Hg between two diffeerent seasons that can be characterized as: (1) the occurrences of peak Hg concentration during daytime(fall0 and (2) slight reductions in daytime Hg concentration relative to nighttiime Hg data(summer). To study the systematic differences in diurnal patterns between two different seasons, we analyzed Hg data in terms of different statistical approaches such as correlation(and linear regression0 and factor analysis. Results of these analyses consistently indicated that different mechanisms were responsible for controlling the daytime distribution patterns of Hg. The variation of boundary layer conditions betwen day/night periods may have been important in introducing the relative reduction in daytime Hg levels during summer. However, when the relationship between Hg and concurrently determined O3 is concerned, these differences are unlikely to be an effective sink mechanism within the ranges of ozone concentrations determined concurrently during this study, regardless of season. To further provide the general account for short-term variations in Hg distribution data, we should be able to describe the various factors underlying its sink mechanism.

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국내 콩 씨스트선충의 HG type 분석 (Studies on HG Type of Heterodera glycines in Korea)

  • 김동근;최인수;한원영;류영현;김명식;배창환
    • 식물병연구
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    • 제19권1호
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    • pp.31-35
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    • 2013
  • 콩 저항성품종 육성의 기초자료로 이용하고자 국내 13개 콩 씨스트선충 집단을 대상으로 HG type를 조사하였다. 국내 콩 씨스트선충 HG type는 0, 2, 5, 2.5, 1.2.7, 2.5.7로 총 6개의 HG type가 발견되었다. 그중 HG type 2.5가 30.8%로 가장 많았으며 다음으로 HG type 2.5.7(23.0%)이었다. 각 indicator별로는 PI 88788 가해 집단이 76.9%, PI 209332 가해 집단이 61.5%, PI 548316('Cloud') 가해 집단이 30.8%, PI 548402('Peking') 가해 집단이 7.7%였고 PI 90763, PI 437654, PI 89772를 가해할 수 있는 콩 씨스트선충 집단은 없었다. PI 90763, PI 437654, PI 89772은 국내 모든 콩 씨스트선충 집단에 대해 저항성으로 나타나 저항성품종 육성 교배 모본으로 이용될 수 있을 것이다.

Correlation Between Total Mercury and Methyl Mercury-In Whole Blood of South Korean

  • Jung, Seon A;Chung, Dayoung;On, Jiwon;Moon, Myeong Hee;Lee, Jeongae;Pyo, Heesoo
    • Bulletin of the Korean Chemical Society
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    • 제34권4호
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    • pp.1101-1107
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    • 2013
  • In this study, total mercury and methyl mercury in whole blood of Korean was analyzed so as to investigate the correlation between total mercury (T-Hg) and methyl mercury (Me-Hg). 4000 whole blood samples were divided in four groups, according to T-Hg concentration in percentile: group I (p25-p50), group II (p50-p75), group III (p75-p95) and group IV (p95-p100). 100 samples were randomly selected from the each group, and Me-Hg concentration was measured. T-Hg concentration in whole blood was analyzed using a Direct Mercury Analyzer-80 and obtained limit of detection (LOD) was $0.2{\mu}gL^{-1}$. Me-Hg concentration was analyzed with ethylate derivatization using headspace-gas chromatography-mass spectrometry, and obtained LOD of methyl mercury was $0.5{\mu}gL^{-1}$. The geometric means of T-Hg and Me-Hg were $6.35{\mu}gL^{-1}$ and $4.44{\mu}gL^{-1}$, respectively, and 71.91% of T-Hg was presented as Me-Hg.

MOVPE GROWTH OF HgCdTe EPILAYER WITH ARSENIC DOPING

  • Suh, Sang-Hee;Kim, Jin-Sang;Song, Jong-Hyeong;Kim, Je-Won
    • 한국표면공학회지
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    • 제29권5호
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    • pp.325-329
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    • 1996
  • We report on p-type arsenic doping of metalorganic vapor phase epitaxially (MOVPE) grown HgCdTe on (100) GaAs. HgCdTe was grown at $370^{\circ}C$ in a horizontal reactor with using dimethy-cadmium, diisoprophyltelluride, and elemental Hg. We used tris-dimethylaminoarsenic (DMAAs) as the metalorganic for p-doping. 4micron thick CdTe and subsequently 10micron thick HgCdTe were grown on (100) GaAs substrate. Interdiffused multilayer process in which thin CdTe and HgTe layers are grown alternately and interdiffused to obtain homogeneous HgCdTe alloys was used. Arsenic was doped during CdTe growth cycle. After growth HgCdTe was annealed at $415^{\circ}C$ for 15 min and then annealed again at $220^{\circ}C$ for 3 hr, both with Hg-saturate condition. We could obtain p-doping from 2.5$\times$$10^{16}$ to 6.6$\times$$10^{17}$$cm^{-3}$, depending on the DMAAs partial pressure. With the dual Hg-annealing, activation of arsenic was aboutt 90%, which was confirmed by SIMS measurement. With only low temperature annealing at $220^{\circ}C$ for 3hr, activation efficiency was about 50%.

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