• The Journal of the Korean dental association
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• v.11 no.3
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• pp.185-189
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• 1973

Dental amalgam in the clinic practice of dentistry is one of the most important materials. Mercury, one of the component of this alloy, is emitted in the form of vapor after filling as long as 5 days Silver particles penetrate into the dentine deeply along the tubles underneath cavity floor. To determine the permeability of mercury in the teeth following experiments were performed. Class 5 cavities total 40 from 10 dogs were prepared on upper and lower canines and amalgam alloys which contain about 10uCi of radioactive mercury were inserted. The animals were sacrificed 7 days after the experiments and the teeth were decalcified, sectioned and autoradiographed by means of emulsion and stained by H & E. Following are the results obtained from this experiments. 1. Blackened silver grains were found along the dentinal tubules underneath the cavity floor. Beyond the border of dentine and pulp chamber grains were seen in odontoblastic layer (Fig. 1, 2, 3, 4) 2. Underneath the odontoblastic layer, the pulp tissue showed almost normal appearance except slight dilatation of blood vessel.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.145-147
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• 2007

Fluorescent induction lamps are assembly of a Low Pressure Mercury discharge vessel and an inductive power coupler. A vessel containing at least a Low Pressure Mercury vapor, which will be energized by means of the Inductive Coupler. The Ultra Violet radiation from the resulting discharge is converted by a layer of fluorescent material into visible light. The discharge vessel may have means of mechanical fixation to position it to the Inductive power coupler. The component to transform High Frequency electrical energy, by means of induction, in order to energize the Low Pressure Mercury in the discharge vessel. The component includes electrical connection. Fluorescent induction lamps don't have international standards yet. So we try to correspond Korea standards to international standards.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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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.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.92-93
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• 1999

수은은 상온에서 액체상태로 존재하는 유일한 금속으로서, 증기압이 매우 높기 때문에 가장 쉽게 휘발될 수 있는 중금속이다. 다른 중금속들은 거의 입자 상태로 변환되기 때문에 전기 집진기 등과 같은 일반적인 입자 제어시설에서 98％이상이 제거되지만, 증기압이 매우 높은 수은은 다단계 습식 스크러버, 활성탄을 사용하는 전기집진기/습식 스크러버가 결합된 특정한 방지시설에 없는 한 거의 대부분이 그대로 배출된다.(중략)

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.44-58
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• 1994

This study was conducted to examine the levels of total and organic mercury in the scalp hair of the elementary school children and adults, and their relationship with the consumption pattern of fishes and shellfishes. The scalp hair samples were collected from the occipital part of 115 children and 131 adults in costal, urban and rural areas of Kyungpook province from June to August 1991. The mercury content was analysed by the atomic absorption spectrophotometer (model IL. 555) with atomic vapor accessory (model IL. 440). The total and organic mercury contents of hair were significantly higher (p<0.01) among the children who prefer fish and/or shellfish (7.728 ppm, 6.610 ppm), and canned fish and/or fish pastes (6.969 ppm, 5.885 ppm) than those who prefer meat (4.822 ppm, 3.905 ppm) and vegetables (3.974 ppm, 3.224 ppm). The children who prefer to eat the canned fish without cooking showed a higher mercury content than the children who prefer to eat it as stew or mixed with vegetables (p<0.01). There was a dose-response relationship between the intake frequency of canned fish, raw fish and cooked fish and the content of total and organic mercury of hair, the children who eat fish almost everyday showed 2 times higher than those who eat rarely (p<0.01). The mercury content in the hair of the children who eat raw fish was significantly higher than that of the children who eat boiled or broiled fish (p<0.01). The total and organic mercury contents of adult scalp hair increased with age up to the forties and slightly decreased in the fifties. The mercury contents of those who were engaged in the fishery and raw fish restaurant were 2 times higher than those of the farmers. The mercury content of the persons who were favorite dishes of fish and shellfish were most high, and who prefer raw fish were 2 times higher than those of the persons who prefer vegetables and broiled fish. The contents of total and organic mercury in adult scalp hair showed also a increasing tendency with the intake frequency of raw and cooked fish.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.12
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• pp.2446-2452
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• 2009

A Ceramic Metal-halide lamp is achieved by adding multiple metals to a basic mercury discharge. Because the vapor pressure of most metals is very much lower than mercury itself, metal-halide salts of the desired metals, having higher vapor pressures, are used to introduce the material into the basic discharge. The metal compounds are usually polyatomic iodides, which vaporize and subsequently dissociate as they diffuse into the bulk plasma. Metals with multiple visible transitions are necessary to achieve high photometric efficiency and good color. Compounds of Sc, Dy, Ho, Tm, Ce, Pr, Yb and Nd are commonly used. The maximum visible efficacy of a Ceramic Metal Halide lamp, under the constant of a white light source, is predicted to be about 450lm/W. This is controlled principally by the chemical fill chosen for a particular lamp. Current these lamps achieve 130lm/W and these life time are the maximum 16,000[hr]. So factors of performance lower are necessary to improve lamp performance. In this paper, we analyzed factors of performance lower by accelerated deterioration test. The lamp was operated with short duration turn-on/turn-off procedure to enhance the effect due to electrode sputtering during lamp ignition. The tested lamp that was operated with a longer turn-on/off(20/20 minutes) showed blackening, changed distance between electrodes and lowered color rendering & color temperature by losses of Dy at 421.18nm, I at 511nm, T1 at 535nm and Na at 588nm compared with the new lamp.

• Journal of the Korean Chemical Society
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• v.38 no.12
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• pp.898-907
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• 1994

The solvent extraction of an inorganic trace mercury in sea water samples was studied using zinc diethyldithiocabamate $Zn(DDC)_2$ as chelating agent. The $Zn(DDC)_2$ which maintained the stability of DDC- in the acidic aqueous solution in the course of extraction was synthesized from NaDDC and $ZnSO_4$ in this laboratory. The trace of mercury(Ⅱ) was extracted at pH 3.0 from 100 ml of sea water into 10ml of chloroform containing 0.05 M $Zn(DDC)_2$ by shaking for 5 minutes. And from the organic phase, the $Hg(DDC)_2$ was back-extracted into 10ml of 1 to 1 mixed acid of each 3% (v/v) nitric acid and hydrochloric acid by shaking for 25 minutes. The mercury back-extracted was determined by a cold vapor atomic absorption spectrophotometry. The trace mercury(Ⅱ) was so successfully extracted that this procedure could be applied to its determination in the sea water. That is, the recoveries of mercury in two kinds of samples into which as given amount of Hg(Ⅱ) was spiked were 90.0% and 93.3%, respectively.

• Korean Journal of Materials Research
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• v.26 no.6
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• pp.298-305
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• 2016

In this work, recent progress on graphene/metal oxide composites as advanced materials for $HgCl_2$ and $CO_2$ capture was investigated. Density Functional Theory calculations were used to understand the effects of temperature on the adsorption ability of $HgCl_2$ and water vapor on $CO_2$ adsorption on CaO (001) with reinforced carbon-based nanostructures using B3LYP functional. Understanding the mechanism by which mercury and $CO_2$ adsorb on graphene/CaO (g-CaO) is crucial to the design and fabrication of effective capture technologies. The results obtained from the optimized geometries and frequencies of the proposed cluster site structures predicted that with respect to molecular binding the system possesses unusually large $HgCl_2$ ($0.1-0.4HgCl_2g/g$ sorbent) and $CO_2$ ($0.2-0.6CO_2g/g$ sorbent) uptake capacities. The $HgCl_2$ and $CO_2$ were found to be stable on the surface as a result of the topology and a strong interaction with the g-CaO system; these results strongly suggest the potential of CaO-doped carbon materials for $HgCl_2$ and $CO_2$ capture applications, the functional gives reliable answers compared to available experimental data.

• The Korean Journal of Food And Nutrition
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• v.13 no.6
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• pp.595-601
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• 2000

The seven trace metals contents of agricultural products in Kwang-ju were investigated to provide the basic data for its residual limits. Ten kinds of agricultural products (onion, welsh onion, garlic, lettuce, cabbage, pepper, spinach, radish, pear, peach) collected within from Kwang-ju in 1999 were analyzed by Mercury Analyzer for mercury. Inductively Coupled Plasma spectrometer and Atomic Absorption spectrophotometer equipped with Vapor Generation Accessory for Cu, Cd, Mn, Pb, Zn and As. Hg contents were not detected in all samples and As content were detected N.D. ∼0.005 ppm. Cd and Pb contents were detected N.D ∼0.088 ppm and N.D.∼0.096 ppm, respectively, Cu, Mn and Zn contents were 0.109∼1.072 ppm. 0.829∼6.195 ppd and 0.731∼6.176 ppm, respectively. The trace metal concentrations of the agricultural products in Kwang-ju called clean area were within the background level which growth is facilitated.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.1
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• pp.11-17
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• 2007

The CCFLs, EEFLs and FFLs use mercury and the operating conditions are different at warm or cold temperature. At start of operation, there may exist a possibility of inhomogeneous operation of lamps or channels of FFL to the very low vapor pressure of mercury at low temperature. In this paper, an inverter with level control block (LCB) was developed to drive LCD backlight using FFL stably at low temperature range. The operation of FFL backlight at $-20^{\circ}C$ was successfully demonstrated by developing inverter with LCB under 130 Watt of power consumption.