• Journal of Preventive Medicine and Public Health
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• 제15권1호
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• pp.111-114
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• 1982

To determine Pb level in blood, we usually .used to pull out about 5ml blood from venous vessel and this sample was digested with acids to decompose organic matter and then determined the Pb contents by Atomic Absorption Spectrophotometer with flame. But recent trend in quan titating Pb in small amount of sample is very much recommended in clinical chemistry specially pediatrics, and industrial hygiene and occupational health area. Authors tried to determine Pb contents in small amount blood of $25{\mu}l$ by using capillary tube method and got the possibility of determination of ng amount of Pb in $25{\mu}l$ whole blood sample without any pretreatment of sample.

• 셀메드
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• 제6권1호
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• pp.3.1-3.4
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• 2016

Consumption of herbal products from the medicinal plants contaminated with heavy metals can cause serious consequences on human health. This is a major concern for traditional and herbal medicine. The present study was carried out to analyze and quantify the levels of six potentially toxic heavy metals namely arsenic, lead, cadmium, mercury, chromium and nickel in ten important Indian medicinal herbs. The air dried raw herbs were processed by microwave assisted wet digestion and analyzed by using atomic absorption spectrophotometer equipped with graphite tube atomizer. Except the chromium content in three plants, all the levels of six heavy metals analyzed were found to be quite below the permissible limits in all the ten raw medicinal herbs analyzed. The present work implies that, regular and systematic screening of raw medicinal herbs is necessary to check the levels of the heavy metal contaminants before using them for consumption or preparation of herbal formulations so that the possible contamination cannot cumulate up to the finished products.

• 한국자기학회지
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• 제5권5호
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• pp.556-560
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• 1995

The absorption properties of Cu-Zn ferrite/rubber composite microwave absorbers with PZT(Lead Zirconate Titanate) additive were evaluated. The composite specimens have prepared by molding and curing the mixture of matrix rubber and Cu-Zn ferrite powders which are synthesized by the coprecipitation method using Fe Cl/sub 3/ .center dot. 6H/sub 2/O, CuCl/sub 2/ .center dot. 2H/sub 2/O and Zn Cl/sub 2/ as a starting raw materials. PZT is used as another filler particles to adjust the material constants of Cu-Zn ferrite/rubber composite specimens. We have found that the material constants of specimens could be controlled by various PZT mixing ratio. On the Cu-Zn ferrite/rubber composite specimens with PZT 10[wt%] additive, the reflection losses were larger than 30[dB] in the frequency range from 2.72 to 4.4[GHz]' by adjusing the thickness.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.161-162
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• 2020

In this study, as part of securing related data, water droplets were dropped on the upper part of the wooden board for flooring in an environment such as floor heating, and the degree of absorption according to the surface temperature change was tested. The test results showed that the contact angle of the surface was low (25℃→40℃) or the droplet was absorbed into the small plate and disappeared. The contact angle of the OSB and MDF was decreased within 30 minutes, but the surface water droplet was maintained longer than the plywood. This is because the surface is coated with hydrophobicity unlike the plywood, but moisture absorption in the cross section after the second processing will not be prevented and it will lead to defect occurrence problem.

• 천문학회보
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• 제41권2호
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• pp.40.2-40.2
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• 2016

The attenuation of starlight by dust in galactic environments is investigated through models of radiative transfer in a spherical, clumpy interstellar medium (ISM). We show that the attenuation curves are primarily determined by the wavelength dependence of absorption rather than by the underlying extinction (absorption+scattering) curve; the observationally derived attenuation curves cannot constrain a unique extinction curve unless the absorption or scattering efficiency is specified. Attenuation curves consistent with the Calzetti curve are found by assuming the silicate-carbonaceous dust model for the Milky Way (MW), but with the $2175{\AA}$ bump suppressed or absent. The discrepancy between our results and previous work that claimed the Small Magellanic Cloud dust to be the origin of the Calzetti curve is ascribed to the difference in adopted albedos; we use the theoretically calculated albedos whereas the previous ones adopted empirically derived albedos from observations of reflection nebulae. It is found that the model attenuation curves calculated with the MW dust are well represented by a modified Calzetti curve with a varying slope and UV bump strength. The strong correlation between the slope and UV bump strength, as found in star-forming galaxies at 0.5 < z < 2.0, is well reproduced if the abundance of the UV bump carriers is assumed to be 30-40% of that of the MW-dust; radiative transfer effects lead to shallower attenuation curves with weaker UV bumps as the ISM is more clumpy and dustier. We also argue that some of local starburst galaxies have a UV bump in their attenuation curves, albeit very weak.

• Journal of Yeungnam Medical Science
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• 제6권2호
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• pp.147-157
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• 1989

산모와 태아에 있어서 혈중연농도를 측정하고 연의 분포양상 및 상관요인을 규명하여 산모와 태아 및 영유아의 건강상의 위해를 예방하기 위하여 1989년 3월 1일부터 동년 3월 31일까지 대구시에 소재한 종합병원 1개소와 산부인과의원 1개소에 분만을 위해 내원한 산모 130명을 대상으로 모체혈과 분만직후의 제대혈을 채취하여 원자화 무염광로를 부착한 원자 흡광 광도계로 분석하여 다음과 같은 결과를 얻었다. 산모의 정맥혈과 제대혈의 평균 혈중연농도는 각각 $17.47{\pm}7.92{\mu}g/d{\ell}$, $15.31{\pm}7.98{\mu}g/d{\ell}$였다. 산모와 신생아의간의 혈중연농도는 상관계수는 0.663이였고 회귀방정식은 Y(제대혈의 연농도)=0.667X(모체혈의 연농도)+3.646였다. 산모의 자연유산력 및 출산시의 산과적 합병증과 산모의 혈중연농도와는 유의한 관계가 없었고, 제대혈의 연농도가 높을수록 출산체중이 적은 경향을 보였으나 통계학적인 의의는 없었으며, 신생아의 성 및 재태연령과 신생아의 혈중연농도와는 유의한 관계가 없었다. 생산직에 근무한 경력이 있는 산모의 경우는 직업이 없었거나 비생산직에 근무했던 산모보다 높은 혈중연농도를 나타내었고 근무했던 기간이 길수록 높은 혈중연농도를 나타내었으나 통계학적으로 유의하지는 않았다. 남편이 직장에서 연에 노출되는 경우 산모의 혈중연농도는 비노출군보다 높았으며 통계학적으로 유의한 차이가 있었다.

• 대한수의학회지
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• 제36권3호
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• pp.709-718
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• 1996

This experiment was carried out to clarify the effect of lead poisoning on the lead and essential trace elements homeostasis of tissues in rats. Fifty female Wistar rats, 7 weeks old, were divided into four experimental groups(B, C, D, and E) and a control(A). The four experimental groups received diets contaminated artificially with 10 (B group), 100 (C group), 1,000 (D group) and 5,000 (E group) ${\mu}g/g$ of lead as lead acetate, respectively. The control group received normal diet. Rats were necropsied on the 4th or 8th week of experimental periods and heart, liver, spleen, kidney, muscle, lung and hair were taken. The tissues were analysed for lead, copper, zinc, iron and calcium content by atomic absorption spectrophotometry. From these experiments following results ware obtained ; In C group, lead content of the heart, liver, kidney and hair were significantly increased both on the 4th and 8th week of experiment. In D and E group, lead content of all tissues including heart, liver, spleen, kidney, muscle, hair and lung were significantly increased in accordance with the lead contamination both on the 4th and 8th week of experiment. In C group, copper content of tissues were significantly increased in the heart, liver, kidney and lung on the 4th week and all tissues on the 8th week of experimental periods. In D and E group, copper content of the liver were significantly increased both on the 4th and 8th week of experiment. But the copper content of tissues were gradually decreased compared with C group in accordance with the lead contamination. Especially the content in spleen, heart or kidney were significantly decreased compared with the control group. The zinc content of kidney, heart, or spleen were decreased in D and E groups whereas the iron and calcium content showed no significant change.

• 환경위생공학
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• 제6권1호
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• pp.95-102
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• 1991

This study was carried out to determine the contamination level of heavy mentals in canned fishes on the market. Contents of tin, lead, iron and zinc were analyzed by Atomic Absorption Spectrophtometer. Contents of total mercury were determined by mercury analyzer. The results were as follows. 1. The highest value of tin was $1.7706{\pm}0.3216$pprn in canned yellow pin & skip jack(mix) tuna, the lowest was 1.2109 ${\pm}$ 0.0769ppm in canned mackerel pike. 2. The highest value of lead was 0.1657 ${\pm}$ 0.0530 pprn in canned yellow pin tuna, the lowest was 0.0335k 0.0100 pprn in canned mackerel pike. 3. The highest value of iron and zinc was 22.5943 ${\pm}$ 0.7945 ppm and 13.4556 ${\pm}$ 0.6774 pprn in canned sardine fish, the lowest was 4.3514 ${\pm}$ 0.3607 pprn and 3.8773 ${\pm}$ 0.1914 pprn in canned albacore tuna. 4. The total mercury contents was detected 0.0531~0.3386 pprn in three kinds of canned tuna and could not be detected with the others.

• Journal of Preventive Medicine and Public Health
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• 제12권1호
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• pp.79-87
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• 1979

Analyses for 6 metals (Cd, Zn, Cu, Ni, Pb, Mn) by Atomic absorption spectrophotometer were made on hair samples of healthy 135 in urban area and 130 in rural area who have not dealt with the above metals in their daily working life. Marksd variations were found. Samples of urban area contained more cadmium, copper, lead and manganese than those of rural area. No sexual difference in mean value could be observed and the amount of metals in hair did not increase with age. And no age dependency was found. There was a statistically significant correlation between the concentrations of cadmium and lead in both urban and rural people; Pb = 1.50 Cd + 6.69 (r = 0.213, p<0.05) in urban area Pb = 1.44 Cd + 3.67 (r = 0.327, p<0.001) in rural area

• 한국환경보건학회지
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• 제11권2호
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• pp.55-63
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• 1985

The quantities of chrome, lead, iron, copper and manganese in the formula feed were determined by A.A.S. and the results were summarized as follows 1. The content of chromium in the leather and meat meals(SN-2) were 13-66 times as much as the level of permission. 2. In the meantime, lead content in the meat meal (SN-1) was about 20 times as much as permitted level. 3. The iron which is essential constituent of the formula feed was contained in the meat and leather meals and these values were 2-10 times as much as feeding regulations, on the contrary copper and manganese content in the shaving and flesh were below the feeding regulations.