• 한국임상수의학회지
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• 제34권6호
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• pp.474-477
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• 2017

We described the successful treatment of cases of lead poisoning in a Whooper swan (Cygnus cygnus) and a Cinereous vulture (Aegypius monachus) in Korea. The swan and vulture rescued were diagnosed with lead poisoning based on clinical signs, the presence of suspected lead-like particles in the ventriculus detected by radiography and elevated blood lead levels. Endoscopic retrieval for the swan and gastric lavage for the vulture were used to remove the lead respectively. After the removal of lead particles, a course of chelation treatment was administrated. This would be the first report of successfully treating wild birds with lead poisoning in Korea.

• Applied Science and Convergence Technology
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• 제24권3호
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• pp.47-52
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• 2015

The correlation between admittance and dielectric spectroscopy of dielectric relaxation in lead scandium noibate, have been investigated. Lead scandium niobate, with composition $PbSc_{0.5}Nb_{0.5}O_3$, was prepared by conventional solid state synthesis. Conductance Y'(G), susceptance Y"(B) and capacitance C of lead scandium niobate as a function of frequency and temperature were measured. From the temperature-dependence of RLC circuit, insight into physical significance of the dielectric properties of lead scandium niobate is obtained. The relative strong frequency dependent of dielectric properties in lead scandium niobate is observed, and the phase transition occurred at a broad temperature region. Also, the value of critical exponent ${\gamma}$=1.6 showed on heating process. The long relaxation times part enlarged diffuse by conductivity effects with increasing temperature, and the ordering between $Sc^{3+}$ and $Nb^{5+}$ in PSN influences complex admittance and dielectric properties. Confirmed the typical characteristic of lead-type relaxor in the Raman spectra of lead scandium niobate and major ranges are between 400 and $900cm^{-1}$.

• 한국환경보건학회지
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• 제22권3호
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• pp.8-16
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• 1996

Effects of water extract of aloe vera on lead-induced neurotoxicity were investigated in sciatic nerve isolated from rat. The mechanism on toxicity reduction by measuring activities of axonal enzymes, metabolism of myo-inositol in nerve, lead concentration in several organs and so on were further examimed. In the lead-treated rats, the transport rate of axonal enzyme, such as acetyl cholinesterase and choline acetyltransferase, was reduced by from 50% to 30% respectively. Reduction in myo-inositol concentration and $Na^+/K^+$ ATPase activity were also observed in sciatic nerve from lead-treated rat. However, the aloe extract administration significantly eliminated the impairment and maintained myo-inositol concentration to about 85% of normal level. Also aloe extract promoted the excretion rate of lead which is accumulated in blood, sciatic nerve and kidney. These results suggest that lead-induced neurotoxicity was significantly reduced by administration of aloe extract and the mechanism might be partly increase in kidney excretion rate of lead and parity normalization of $Na^+/K^+$ ATPase activity which is critical factor in order to keep nerve maintaining normal myo-inositol level.

• 대한수의학회지
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• 제24권1호
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• pp.24-30
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• 1984

The protective effects of high levels of dietary iron, copper, zinc or protein on lead toxicity were studied In chicks. Growth retardation, reduction of feed intake, anemia and accumulation of lead in the bone and kidney were observed in chicks fed a diet containing 500mg lead as chloride per kg of feed for 42 days. Early changes due to ingested lead were inhibition of red blood cell ${\delta}$-aminolevulinic acid dehydrase at all doses and no effect of iron, copper, zinc or protein addition were observed. Tibia lead accumulation was reduced in chicks receiving additional dietary iron or zinc compared to the lead only group but increased in chicks given supplementary protein. Decreased body weight gain was overcome by supplementary zinc or protein in chicks fed lead but not by supplementary iron. Overall the results of this study show that lead poisoning can be partly reduced by providing supplementary iron, zinc or protein, but the interaction of these element remained to be elucidated.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.144-144
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• 1998

The physiological responses caused by exposure of high- and low-level lead exhibit different phase. Low-level lead continuous hypertension, but high-level lead can in the development of hypertension. In this study it was tested which difference can be caused as lead levels and, if it can be caused, whether hematological changes are related with the hypertensive effects induced by different levels of lead exposure was tested. Lead intoxication in male SD rats was induced by exposure through drinking water containing 50, 200 and 1000 ppm lead (as lead acetate). The animals of control group was supplied drinking water containing sodium acetate ad libitum. The number of each animal group was 10. Systolic blood pressures were measured in the unanesthetized state by the tail-cuff technique at 0, 3, 7 and 16 weeks. RBC, WBC, MCV, hemoglobin, hematocrit and whole blood viscosity levels were examined.

• 한국수산과학회지
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• 제30권6호
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• pp.936-943
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• 1997

Biosorbents of nonliving, dried marine brown algae Undaria pinnatifida, Hizikia fusiformis, and Sargassum fulvellum were investigated for their lead biosorption performances. As the amount of biosorbent added was increased, the lead removal by biosorbent materials increased but the lead biosorption capacities decreased. However the lead biosorption capacity by the biosorbent materials increased with increasing initial lead concentration and pH in the range of $C_o\;10\~500\;mg/L$. Among the biosorbent materials used in this study, the lead biosorption capacity in the solutions with no pH adjustment decreased in the following sequence: U. pinnatifida > H. fusiformis > S. fulvellum. Equilibrium parameters based on Langmuir and Freundlich isotherm were determined. It was found that the lead biosorption by biosorbent materials were expressed by the Langmuir isotherm better than the Freundlich isotherm.

• Journal of Power Electronics
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• 제13권3호
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• pp.497-506
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• 2013

This paper proposes a new method to improve the available battery capacity in electric vehicles by connecting lead-acid batteries with lithium-ion battery in parallel to supply power. In addition, this method combines the discharge characteristics of batteries to improve their efficiency and lower their cost for electric vehicles. A lithium-ion battery set is used to connect with N sets of lead-acid batteries in parallel. The lead-acid battery supplies the initial power. When the lead-acid battery is discharged by the load current until its output voltage drops to the cut-off voltage, the power management unit controls the lead-acid battery and changes it to discharge continuously with a small current. This discharge can be achieved by connecting the lead-acid battery to a lithium-ion battery in parallel to supply the load power or to discharge its current to another lead-acid or lithium-ion battery. Experimental results demonstrates that the available capacity can be improved by up to 30% of the rated capacity of the lead-acid batteries.

• 대한기계학회논문집A
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• 제28권12호
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• pp.1856-1863
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• 2004

In the last 50 years, lead-contained solder materials have been the most popular interconnect materials used in the electronics industry. Recently, lead-free solders are about to replace lead-contained solders for preventing environmental pollutions. However, the reliability of lead-free solders is not yet satisfactory. Several researchers reported that lead-contained solders have a good fatigue property. The others published that the lead-free solders have a longer thermal fatigue life. In this paper, the reason for the contradictory results published on the estimation of fatigue life of lead-free solder is investigated. In the present study, fatigue behavior of 63Sn37Pb, and two types of lead-free solder joints were compared using pseudo-power cycling testing method, which provides more realistic load cycling than chamber cycling method does. Pseudo-power cycling test was performed in various temperature ranges to evaluating the shear strain effect. A nonlinear finite element model was used to simulate the thermally induced visco-plastic deformation of solder ball joint in BGA packages. It was found that lead-free solder joints have a good fatigue property in the small temperature range condition. That condition induce small strain amplitude. However in the large temperature range condition, lead-contained solder joints have a longer fatigue life.

• Biomolecules & Therapeutics
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• 제7권4호
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• pp.322-328
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• 1999

In this study, it was tested whether the changes of catecholamines and its metabolites are related with the changes of blood pressure(BP) induced by different levels of lead exposure. Adult male SD rats were exposed to lead by giving drinking water containing 50(low doses), 200 and 1,000 ppm(high doses) of lead(as lead acetate) or sodium acetate(for control groups, supplying an identical amount of acetate) for 7 or 16 weeks. The systolic BP was measured in the unanesthetized state by the tail-cuff technique. Levels of catecholamines and its metabolites in urine were measured by HPLC-ECD. Rats receiving 200 and 1,000 ppm developed an elevation of systolic BP at 3 and 7 weeks compared with week 0, but blood pressure levels at 16 weeks returned to normal. For the 50 ppm lead treated group, systolic BP increased significantly at 7 weeks and 16 weeks. The concentrations of norepinephrine and VMA in the urine of lead exposed rats changed similarly to the changes of blood pressure, but blood viscosity levels in all lead treated rats increased continuously during all lead treatment periods. This result suggests that the changes of catecholamines and its metabolites in urine by lead intoxication may influence the changes of blood pressure.

• 한국산업보건학회지
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• 제8권2호
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• pp.224-230
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• 1998

In order to provide a basic data for the prevention of the adverse effect of lead on health, We examined lead level in the blood and urine of 371 healthy men living in Choongchung-do from May to June, 1997. The results were as follows ; 1. Average lead level of all the subjects was $3.98{\pm}1.02{\mu}g/dl$ in blood, and $3.94{\pm}2.09{\mu}g/L$ in urine, respectively. Lead contents examined in this study were significantly lower than those of other investigators. 2. The lead levels of all the subjects in blood and urine had almost normal distribution. 3. Relation between lead content in blood and urine was a simple linear regression; its equation was "Lead level in blood=36.76+0.77 lead level in urine".