• Journal of Plant Biology
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• v.20 no.1
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• pp.7-14
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• 1977

The seeds of bean(Glycine max M.) and corn(Zea mays L.) soaked in 5000ppm lead solution for 24 hours were sowed in the flowerpots being placed sandy-clay soil under the field condition. The fixed concentrations of various anions and 2000 ppm lead were supplied alternately in the sandy-clay soi of the flowerpots at two days interval from May to July in 1976. After the plants were harvested prior to the flowering stage, the lead contents of plnat and soil were analyzed by atomic absorption spectrophotometer. The lead contents absorbed by the plant roots showed the highest in an weak acid soil of the best suitable condition of plant growth. The absorption of lead by the plant roots was inhibited by the various anions, especially divalent anions of the soil. Some phosphate anions inhibited lead absorption more than otehr various anions in the soil. The more various anions were in the soil, the more plants could be protected from the lead toxicity. In the case of lead supply in the soil, 99.5% of lead was accumulated in the upper layer of the soil(0-10cm), and 0.5% of lead accumulated in the lower layer (10-20cm). Therefore, the yellow-brown and white symptoms on the leaves and the inhibition of root growth by lead toxicity was increased in the early stage of the germination, however decreased in accordance with the progress of the growing stage becuase of the root growth toward beneath the lower layer of the soil. In spite of the contents of 3773ppm lead in the soil, the symptoms of lead toxicity was not found in the grown plants. At that time the lead contents of the plants absorbed from the soil were minimum 0.78ppm and maximum 3.64ppm through the growing stage.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.63-67
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• 1989

In order to examine the suppressive effect of dietary fiber toward the intestinal absorption of lead, an in vitro absorption test using a semipermeable membrane was undertaken. Among dietary fiber components, cellulose showed no suppressive effect, guar gum and carboxymethyl-cellulose, a slight effect whereas citrus pectin and sodium alginate exhibited a remarkable effect. Among fibrous foods tested, rice bran, wheat bran, Chinese cabbage, radish and tangle had a higher suppressive effect while mandarin orange, apple and laver showed a lower effect.

• Clinical and Experimental Pediatrics
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• v.57 no.8
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• pp.345-350
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• 2014

Iron deficiency affects approximately one-third of the world's population, occurring most frequently in children aged 6 months to 3 years. Mechanisms of iron absorption are similar to those of other divalent metals, particularly manganese, lead, and cadmium, and a diet deficient in iron can lead to excess absorption of manganese, lead, and cadmium. Iron deficiency may lead to cognitive impairments resulting from the deficiency itself or from increased metal concentrations caused by the deficiency. Iron deficiency combined with increased manganese or lead concentrations may further affect neurodevelopment. We recently showed that blood manganese and lead concentrations are elevated among iron-deficient infants. Increased blood manganese and lead levels are likely associated with prolonged breast-feeding, which is also a risk factor for iron deficiency. Thus, babies who are breast-fed for prolonged periods should be given plain, iron-fortified cereals or other good sources of dietary iron.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2019-2022
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• 2016

In the presence of an electrically conducting medical lead, radio frequency (RF) coils in magnetic resonance imaging (MRI) systems may concentrate the RF energy and cause tissue heating near the lead. A novel design for a medical lead to reduce this heating by introducing pins in the lead is presented. Peak 10 g specific absorption rate (SAR) in heart tissue, an indicator of heating, was calculated and compared for both conventional (Medtronic) lead design and our proposed design. Remcom XFdtd software was used to calculate the peak SAR distribution in a realistic model of the human body. The model contained a medical lead that was exposed to RF magnetic fields at 64 MHz (1.5 T), 128 MHz (3 T) and 300 MHz (7 T) using a model of an MR birdcage body coil. The proposed design of adding pins to the medical lead can significantly reduce the heating from different MRI systems.

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.545-549
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• 2002

A simple and rapid technique for the separation and preconcentration of lead in water and biological samples has been devised. Preconcentrationis based on the depositionof analyte onto a column packed with dithizone immobilized on sodium dodecyl sulfate coated alumina at pH $\geq$ 3. The trapped lead is eluted with 5 mL of 4 M nitric acid and determined by flame atomic absorption spectroscopy. A sample of 1 L, results in a preconcentration factor of 200 and the precision at 20${\mu}g$ $L^{-1}$ is 1.3%(n=8). The procedure is applied to tap water, well water, river water, vegetable extract and milk samples, and accuracy is assessed through recovery experiments and by independent analysis by furnace atomic absorption.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.1-6
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• 1973

• Analytical Science and Technology
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• v.6 no.4
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• pp.363-368
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• 1993

Blood lead concentrations of occupationally exposed workers were measured by the atomic absorption spectrometry with graphite furnace. The concentrations of the unexposed group were also checked and compaired with those of the exposed one. The correlation of smoking habit and work duration with the blood lead concentration was also surveyed.

• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1783-1790
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• 2023

Barium Bismuth Oxide Borate (BBOB) has been synthesized for the first time using solution combustion technique. SEM analysis reveal flower shape of the nanoparticles. The formation of the nanoparticles has been confirmed through XRD & FTIR studies which gives the physical and chemical structure of the novel material. The UV light absorption is observed in the range 200-300 nm. The present study highlights the radiation shielding ability of BBOB for different radiations like X/Gamma rays, Bremsstrauhlung and neutrons. The gamma shielding efficiency is comparable to that of lead in lower energy range and lesser than lead in the higher energy range. The bremsstrauhlung exposure constant is comparably larger for BBOB NPs than that of concrete and steel however it is lesser than that of lead. The beauty of BBOB nanoparticles lies in, high absorption of radiations and low emission of secondary radiations when compared to lead. In addition, the neutron shielding parameters like scattering length, absorption and scattering cross sections of BBOB are found to be much better than lead, steel and concrete. Thus, BBOB nanoparticles are highly efficient in absorbing X/Gamma rays, neutrons and bremsstrauhlung radiations.

• Journal of Preventive Medicine and Public Health
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• v.7 no.2
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• pp.377-381
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• 1974

Determination of lead in urine is important in industrial hygiene and toxicology. Dithizone method has been principally used for the determination of lead in urine, which gives accurate results in skilful hands but is usually complex and time-consuming. Atomic absorption spectrophotometry is a new simple method and several procedures have been described. However, the influences of pH and the presence of chelating agents during treatment of lead poisoning are not clear. The purpose of this study was to find out the effect of pH and chelating agents on the determination of lead using Shimadzu atomic absorption/flame spectrophotometer, model AA-610. The results obtained were as follows: 1. The atomic absorption spectrophotometry(AAS) could be applied without prior acid digestion to specimens in the absence of chelating agents. The absorbance at $2,170\;{\AA}$, though more sensitive, was more noisy electronically. Therefore, we selected the wavelength of $2,833\;{\AA}$ plus scale expansion. 2. The optimal pH was in the range from 2 to 3. 3. The sensitivity was $0.075{\mu}g/ml/%$ and detection limit was about $0.2{\mu}g/ml$. 4. In the presence of EDTA, lead could not be completely determined without prior acid digestion. 5. On specimens from patients receiving penicillamine therapy, a comparison was made between the values obtained with dithizone method and AAS method with prior acid digestion. The results of comparison showed a very good agreement.

• Journal of the Korean Society of Radiology
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• v.16 no.4
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• pp.419-425
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• 2022

In the medical field, lead aprons are used to protect the human body from radiation. However, lead is a heavy metal that is harmful to the human body and the environment, so various shield are being developed. In this study, bismuth, which has a similar atomic number to lead, was set as a new material and the absorption rate according to thickness in the same energy region was compared and evaluated through Monte Carlo simulation. The same tendency was confirmed when the thickness of the lead shield was 0.25 mm, the thickness of the bismuth was 0.3 mm, when the lead was 0.50 mm, the bismuth was 0.60 mm, and when the lead was 0.75 mm, the bismuth was 0.90 mm. Therefore, it is reasonable to replace lead with bismuth in the shield material.