• 자원리싸이클링
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• 제7권2호
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• pp.31-38
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• 1998

2차납 제련공정에서 발생한 주성분이 황산납인 연진으로부터 고부가가치제품인 정제 질산납을 생산하는 습식공정을 개발하였다. 본 공정은 탄산염에 의한 탄산화 공정과 저농도 질산용액을 이용한 침출공정 및 정제 공정으로 구성되어 있으며 본 공정을 통하여 99%이상의 순도를 가진 질산납을 제조할 수 있었다.

• Journal of Preventive Medicine and Public Health
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• 제9권1호
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• pp.87-94
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• 1976

In order to study the chelating action of d-penicillamine on lead and the possibility of its application to the provocation test for diagnosis of lead poisoning, urinary excretion of lead was measured from 24-hour urine samples before, during and after administration of d-penicillamine by oral route for 5 days on 18 lead workers. The results were as follows: 1. Oral d-penicillamine 600 mg/day raised the excretion of urinary lead by approximately 3 times as compared with initial urinary lead level. 2. Initial urinary lead level was the better indicator of urinary lead excretion in d-penicillamine administration than initial blood lead ${\delta}-ALA$ and hemoglobin level. 3. Oral d-penicillamine may be quite useful in provocation test for lead poisoning.

• Toxicological Research
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• 제12권2호
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• pp.283-288
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• 1996

This study was performed to investigate the effects of chitosan on the lead poisoning in rats. For this experiment, 15 male Sprague-Dawley rats were used. The experimental groups were divided into five: Control (250 mg/kg lead), Group I (250 mg/kg lead+1% chitosan), Group II (250 mg/kg lead+2% chitosan), Group III(250 mg/kg lead+4% chitosan), Group IV (250 mg/kg lead+8% chitosan). The results were as follows; 1. The lead concentration in the liver showed 3.924~10.217 mg/kg in control group, but treated group was inclined to decrease during the experiment period (P<0.05). 2. The lead concentration in the kidney showed 23.268~31.315 mg/kg in control group, but Experimental group showed 3.765~9.725 mg/kg (Group I), 34.60~9.115 mg/kg (Group II), 3.549~8.816 mg /kg (Group III), 3.502~8.532 mg/kg (Group IV) resectively, also, Experimental group was inclined to decrease compared to control group (P

• 대한임상검사과학회지
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• 제41권2호
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• pp.67-75
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• 2009

In order to provide basic data for the prevention of adverse effects of lead on health, we examined lead levels in the blood of 30 handicapped workers employed in manufacturing electronic components in Seoul from 2002 to 2008. The average lead level in the blood of all the subjects was $4.79{\pm}4.32{\mu}g/dL$ in females, $2.64{\pm}2.31{\mu}g/dL$ in males, and $3.88{\pm}3.75{\mu}g/dL$ in total. Lead levels examined in this study were significantly lower than other investigators study have reported. The average lead level from personal exposure of the subjects was $1.44{\pm}0.91mg/m^3$ in the workplace. The relation between blood lead levels and personal exposure was a simple linear regression; it's equation was "Lead level in blood = 6.04 - 1.92 lead level by personal exposure".

• Journal of Preventive Medicine and Public Health
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• 제11권1호
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• pp.76-82
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• 1978

In order to study the change of laboratory parameters of lead poisoning, 8 persona who had not been treated previously for lead poisoning (Group 1 and 6 persons who had been inadequately treated for few months for chronic lead poisoning at local clinic (Group 2) were examined. They had occupational exposure to lead for 3 to 18 years (mean, 7.6). In group 1 blood lead, urine lead, urine coproporphyrin and ${\delta}$-aminolevulinic acid levels before our treatment exceeded the critical levels of lead poisoning. In group 2 urine lead level exceeded but blood lead, urine coproporphyrin and ${\delta}$-aminolevulinic acid levels were within normal limits. All of them were treated with D-penicillamine for 4 months as inpatients at Industrial Accident Hospital. The dose of D-penicillamine was the same in all patients; 600 mg per day p.o. and the chelating agent was administer every other week. For laboratory analysis, 24 hour urine and 10 gm of whole blood were collected every 1 month on last day of non-administration period. The results were as follows: 1. It was found that urine lead level was decreased below the cirtical level of lead poisoning after 4 month's treatment with D-penicillamine and blood lead level was decreased more progressively below the critical level after 1 month treatment. 2. Urine coproporphyrin and ${\delta}$-aminolevulinic acid levels were decreased progressively to normal range after 1 month treatment. 3. Two months after treatment, blood lead, urine lead, urine coproporphyrin and ${\delta}$-aminolevulinic acid levels showed some increasing trends. 4. Urine lead level should be checked in a person who had been inadequately treated with chelating agents because blood lead, coproporphyrin and ${\delta}$-aminolevulinic acid might be in normal range.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.1-7
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• 2015

The most critical health effect of lead exposure is the neurodevelopmental effect to children caused by the increased blood lead level. Therefore, the endpoint of the risk assessment for lead-contaminated sites should be set at the blood lead level of children. In foreign countries, the risk assessment for lead-contaminated sites is conducted by estimating the increased blood lead level of children via oral intake and/or inhalation (United States Environmental Protection Agency, USEPA), or by comparing the estimated oral dose to the threshold oral dose of lead, which is derived from the permissible blood lead level of children (Dutch National Institute for Public Health and the Environment, RIVM). For the risk assessment, USEPA employs Integrated-Exposure-Uptake-Biokinetic (IEUBK) Model to check whether the estimated portion of children whose blood lead level exceeds 10 µg/dL, threshold blood lead level determined by USEPA, is higher than 5%, while Dutch RIVM compares the estimated oral dose of lead to the threshold oral dose (2.8 µg/kg-day), which is derived from the permissible blood lead level of children. In Korea, like The Netherlands, risk assessment for lead-contaminated sites is conducted by comparing the estimated oral dose to the threshold oral dose; however, because the threshold oral dose listed in Korean risk assessment guidance is an unidentified value, it is recommended to revise the existing threshold oral dose described in Korean risk assessment guidance. And, if significant lead exposure via inhalation is suspected, it is useful to employ IEUBK Model to derive the risk posed via multimedia exposure (i.e., both oral ingestion and inhalation).

• 한국광물학회지
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• 제28권2호
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• pp.187-193
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• 2015

익산 미륵사지 석탑의 사리공 내에서 출토된 납유리 9점의 납동위원소비를 분석하여 납 원료의 산지를 추정하고, 이를 왕궁리 출토 납유리의 연구결과와 비교하여 상관관계를 알아보고자 하였다. 납유리는 주화학성분 분석결과, PbO가 약 70 wt.%, $SiO_2$가 약 30 wt.% 함유된 전형적인 $PbO-SiO_2$계의 유리였다. 납동위원소비를 이용한 납유리의 원료산지 추정결과, 기존 동북아시아 납동위원소비 분포도로는 대부분이 한국북부의 방연석 광산에 속하는 것으로 나타났다. 반면, 한반도 납동위원소비 분포도로는 한국남부의 방연석 광산이 납유리의 주요 원료 산지로 추정할 수 있어 두 분포도의 결과가 상이하게 나타났다. 또한 동일지역, 동시대에 조성된 것으로 알려진 왕궁리 출토 납유리의 기존 연구데이터와 비교한 결과, 납 원료의 산지가 서로 유사한 것으로 판단된다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1774-1777
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• 1997

As factory automation is required, using the vision system is also essential. Especially, the pateh planning of parts with J-lead on PCB plays a import role of whole automation. Path planning is required because J-lead is scatteed compaed to L-lead on PCB. Therefore, in this paper, we propose path planning of part inspection with J-lead to use Hopfield Model(TSP : Traveling Salesman Problem). Then optical system suited to J-lead inspection is designed and the algorithm of J-lead solder joint and part inspection is proposed.

• Journal of Preventive Medicine and Public Health
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• 제24권2호
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• pp.181-194
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• 1991

This study intended to obtain an useful information on the prevalence of subjective symptoms, and to clarify the interrelationships between blood lead and lead related symptoms in low level lead exposure. The 93 male workers exposed to lead and 56 male nonexposed workers were examined for their blood lead(PBB), Zinc-protoporphy(ZPP), hemoglobin(HB) and personnal history, and completed 15 questionnaires related to symptoms of lead absorption : also measured lead concentration in air (PBA) in the workplace. The results obtained were as follows ; 1. The means of blood lead (PBB), blood ZPP and hemoglobin (HB) among workers exposed to lead were $26.1{\pm}8.8{\mu}g/dl,\;28.3{\pm}26.0{\mu}g/dl$ and $16.2{\pm}1.2g/dl$ : whereas those of nonexposed workers were $18.7{\pm}5.1{\mu}g/dl,\;20.6{\pm}8.7{\mu}g/dl$ and $17.3{\pm}1.1g/dl$. The means of above three indicies between two groups showed significant difference statistically (p<0.05). 2. The means of blood lead (PBB), blood ZPP and hemoglobin of workers exposed .to different lead concentration in air were as follows : When it was below $25{\mu}g/m^3$, the indices were $24.7{\pm}79,\;26.1{\pm}26.8{\mu}g/dl\;and\;16.4{\pm}1.1g/dl$ respectively : These indices were $27.1{\pm}8.5,\;23.9{\pm}10.92{\mu}g/dl\;and\;16.2{\pm}1.3g/dl$ when the lead concentration in air was $25{\sim}50{\mu}g/m^3$ : and they were $3.4{\pm}9.3,\;42.3{\pm}31.3{\mu}g/dl\;and\;15.5{\pm}1.2g/dl$ when the concentration of lead was above $50{\mu}g/m^3$. Although there were statistical difference in blood lead and hemoglobin among three different lead concentration in air, there was no statistical difference of blood ZPP among the three groups with different exposure levels (p>0.05). 3. The most frequent by complained symptom was 'Generalized weakness and fatigue', and fewest symptom was 'Intermittent pains in abdomen' 4. Only two symptoms out of fifteen symptoms checked by themselves revealed significant difference between exposed and nonexposed groups. These were 'Intermittent pains of abdomen' and 'Joint pain or arthralgia' (p<0.05), No positive correlation was found between the levels of blood lead and symptom groups categorized as gastrointestinal, neuromuscular and constitutional symptoms, 5. Blood lead (r=0.3995) and ZPP (r=0.2837) showed statistically significant correlation with mean lead concentration in air, whereas correlations were not demonstrated between blood lead and lead related symptoms or blood ZPP and lead related symptoms. 6. Blood lead (PBB) and ZPP showed association (r=0.2466) and the equation PBB=23.75+0.0842 ZPP was derived. 7. On stepwise multiple regression, using blood lead level as a dependent variable and ZPP, hemoglobin (HB), age, work duration (WD) and symptom prevalence as a independent variables, only ZPP significantly contributed a lot to blood lead level. 8. While the ZPP measurement was found to be a good indicator in evaluating health effect of lead absorption in low level lead exposure, lead related symptoms were not sensitive enough to evaluate of lead absorption in low level exposure.

• Environmental Engineering Research
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• 제12권3호
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• pp.101-108
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• 2007

Fixation of lead contaminants in the solidification/stabilization using Portland cement has been investigated by X-ray diffraction, scanning electron microscopy and compressive strength. The presence of lead was observed to produce lead carbonate sulfate hydroxide ($Pb_4SO_4(CO_3)_2(OH)_2$), lead carbonate hydroxide hydrate ($3PbCO_3{\cdot}2Pb(OH)_2{\cdot}H_2O$) and two other unidentified lead salts in cavity areas and was observed to significantly retard the hydration of cement. By 28 days, howevere, the XRD peaks of most of the lead precipitates have essentially disappeared with only residual traces of lead carbonate sulfate hydroxide and lead carbonate hydroxide hydrate evident. After 28 days of curing, hydration appears well advanced with a strong portlandite peak present though C-S-H gel peaks are not particularly evident. Lead species produced with the dissolution of lead precipitates are fixed into the cement matrix to be calcium lead silicate hydrate (C-Pb-S-H) during cement-based solidification.