• 약학회지
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• 제39권2호
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• pp.148-152
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• 1995

For comparison between the compromised experimental condition and the best conditions for each element by flame atomic absorption spectrometer, the absorbances were measured with changing the burner height and HCL current. The optimum absorbance for simultaneous analysis of 6 elements was observed at 1 mA of HCL current and at 4 mm of burner height except Cr and Co. The stability of flame atomic absorption spectrometer on each element was found to be better than 5%. To investigated the accuracy of this instrument, POSCO RM-07 as a real sample was analysed at these compromised experimental conditions and found to be better than 0.04%.

• 한국광학회:학술대회논문집
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• 한국광학회 2001년도 하계학술발표회
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• pp.180-181
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• 2001

• 분석과학
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• 제6권4호
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• pp.359-362
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• 1993

원자흡수분광법으로 여러 원소를 동시분석시 최적 조건을 위하여 연료의 종류, 연료의 양 및 버너 높이의 변화에 대해 10가지 원소의 흡광도를 측정하였다. Air-$C_2H_2$를 연료로 과량을 사용하고, 버너 높이가 2mm일 때 최적 흡광도를 나타내었고, 이때 10가지 원소의 상대흡광도의 평균은 73%였다.

• 분석과학
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• 제14권3호
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• pp.253-258
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• 2001

본 연구에서는 우리나라 생활폐기물 대형소각시설(200톤/일 이상) 9개소에서 발생되는 소각재중, 바닥재에 대한 금속류의 용출시험 및 함량시험을 수행하여 유해특성과 유해잠재성을 고찰하였다. 용출시험은 우리나라 폐기물공정시험방법에 따라 수행하였으며, 함량시험은 수은(Hg)의 경우 열분해금아말감원자흡광분광기(TDA-AAS)로 측정하고, 납 등 9개 원소는 US-EPASW-846 3050B방법으로 전처리하고 불꽃원자흡광분광기(FAAS) 또는 유도결합플라스마원자발광분광기(ICP-AES)로 측정하였다. 용출시험 결과, 납과 구리가 주 오염물질이었다. 함량시험결과, 철이 가장 높은 농도로 나타났고 농도는 Fe>Zn>Cu>Mn>Pb>Cr>As>Cd>Hg 순으로 나타났으며, 각 소각시설마다 농도순이 평균적으로는 같았다.

• 한국환경보건학회지
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• 제30권1호
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• pp.29-40
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• 2004

This study was performed to investigate and assess the composition of mineral and macronutrient contents in Korean cow′s milk.48 individual farm raw milk, 10 plant raw milk and 29 market milk were collected from June to August in 2003. The minerals such as calcium(Ca), potassium(K), magnesium(Mg), sodium(Na), zinc(Zn), iron(Fe) and phosphorus(P) were determined by using atomic absorption spectrometer(AAS). The macronutrients such as fat, protein and lactose were tested by using IR spectrometer. The obtained analytical results of minerals(mg/100 g) and rnaetronutrients (％) are as follows：1. In case of raw cow′s milk ； Ca 113.56, K 144.09, Mg 10.86, Na 42.53, Zn 0.42, Fe 0.030, p 113.32, fat 3.85, protein 3.08, lactose 4.80,2. In case of market cow′s milk ; Ca 103.04, K 142.46, Mg 10.27, Na 43.21, Zn 0.40, Fe 0.034. p 97.30, fat 3.78, protein 3.05, lactose 4.70,3. In case of fortified market cow′s milk ; Ca 165.40, K 145.79, Mg 10.57. Na 42.55, Zn 0.57, Fe 0.414, p 94.68, fat 3.74, protein 3.08, lactose 4.68,4. In case of processed market cow′s milk ; Ca 134.72, K 142.74, Mg 10.33, Na 45.07, Zn 0.50, Fe 0.650, p 92.48, fat 3.72, protein 3.07, lactose 4.74. According to the group of market milk(milk, fortified market row′s milk, processed market cow′s milk), the mean concentration of Ca and Fe were significantly higher in fortified and processed milk than milk(p<0.05). There were no significant differences in macronutrient(fat, protein, lactose) and mineral contents between pasteurized milk and UHT(ultra high temperature) treated milk($\alpha$=0.05). The labeled "Nutritional Facts" of market milk were satisfied with "Labeling Standards for Livestock Products of Korea". The measured mean concentrations of Ca, Fe, Zn were generally higher than lower limit of labeled value(above 80% of labeled value). The mean concentration of sodium was lower than upper limit of labeled value(below 120％ of labeled value).

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.22-28
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• 2017

The accuracy of analytical results in response to the use of different additives ($NH_4Cl$, KCl, $LaCl_3$) and oxidant gases was evaluated and compared by using Atomic Absorption Spectrometry (AAS). Identification of spectroscopic interferences and possible improvements in Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) analysis were also discussed. The average accuracies of total chromium using Certified Reference Materials (CRMs) were found to be 72.1~94.2% in air/acetylene flame condition by AAS, and they were improved to 100.5~110.5% when the oxidants was changed to nitrous oxide rather than adding the additives. The field samples showed similar trends to CRMs, but chromium concentrations were highly variable depending on analytical conditions. The average accuracies using CRMs were estimated to be 89.3~166.1% by ICP-AES, and improved to below 121.7% after eliminating iron interference. Field samples with low chromium and high iron concentration were measured to be > 30% lower in total chromium concentrations by ICP-AES than AAS in nitrous oxide/acetylene flame. Total chromium concentrations in soil could be analyzed with better accuracy under nitrous oxide/acetylene flame by AAS because it was more effective to increase the temperature of the flame than to eliminate the chemical interference for maximizing atomization of chromium. When using ICP-AES, interference substances, total chromium levels, and analytical conditions should be also considered.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.5-6
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• 2002

The new spectrometer for X-ray Induced Electron Emission Spectroscopy (XIEES) .has been recently developed in KRISS in collaboration with PTI (Russia). The spectrometer allows to perform research using the XAFS, SXAFS, XANES techniques (D.C.Koningsberger and R.Prins, 1988) as well as the number of techniques from XIEES field(L.A.Bakaleinikov et all, 1992). The experiments may be carried out with registration of transmitted through the sample x-rays (to investigate bulk samples) or/and total electron yield (TEY) from the sample surface that gives the high (down to several atomic mono-layers in soft x-ray region) near surface sensitivity. The combination of these methods together give the possibility to obtain a quantitative information on elemental composition, chemical state, atomic structure for powder samples and solids, including non-crystalline materials (the long range order is not required). The optical design of spectrometer is made according to Johannesson true focusing schematics and presented on the Fig.1. Five stepping motors are used to maintain the focusing condition during the photon energy scan (crystal angle, crystal position along rail, sample goniometer rail angle, sample goniometer position along rail and sample goniometer angle relatively of rail). All movements can be done independently and simultaneously that speeds up the setting of photon energy and allows the using of crystals with different Rowland radil. At present six curved crystals with different d-values and one flat synthetic multilayer are installed on revolver-type monochromator. This arrangement allows the wide range of x-rays from 100 eV up to 25 keV to be obtained. Another 4 stepping motors set exit slit width, sample angle, channeltron position and x-ray detector position. The differential pumping allows to unite vacuum chambers of spectrometer and x-ray generator avoiding the absorption of soft x-rays on Be foil of a window and in atmosphere. Another feature of vacuum system is separation of walls of vacuum chamber (which are deformed by the atmospheric pressure) from optical elements of spectrometer. This warrantees that the optical elements are precisely positioned. The detecting system of the spectrometer consists of two proportional counters, one scintillating detector and one channeltron detector. First proportional counter can be used as I/sub 0/-detector in transmission mode or by measuring the fluorescence from exit slit edge. The last installation can be used to measure the reference data (that is necessary in XANES measurements), in this case the reference sample is installed on slit knife edge. The second proportional counter measures the intensity of x-rays transmitted through the sample. The scintillating detector is used in the same way but on the air for the hard x-rays and for alignment purposes. Total electron yield from the sample is measured by channeltron. The spectrometer is fully controlled by special software that gives the high flexibility and reliability in carrying out of the experiments. Fig.2 and fig.3 present the typical XAFS spectra measured with spectrometer.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.133-137
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• 2004

In this paper, we investigated impurities content, absorption properties, and thermal properties showing by changing the content of carbon black which is semiconductive materials for underground power transmission. Specimens were made of sheet form with the three of existing resins and the nine of specimens for measurement. Impurities content of specimens and absorption properties were measured by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometer) and Karl Fisher. And high temperature, heat degradation initiation temperature, and heat weight loss were measured by TGA (Thermogravimetric Analysis). The dimension of measurement temperature was 0$[^{\circ}]$ to 800$[^{\circ}]$, and rising temperature was 10$[^{\circ}/min]$. Impurities content was highly measured according to increasing the content of carbon black from this experimental result also absorption amount was increased according to these properties. Specially, impurities content values of the A1 and A2 of existing resins were measured more than 4000[ppm]. Heat degradation initiation temperature from the TGA results was decreased according to increasing the content of carbon black. All over, heat stabilities were EEA>EBA>pEVA. That is, heat stabilities of EVA containing the weak VA(vinyl acetate) against heat was measured the lowest.

• Nuclear Engineering and Technology
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• 제48권5호
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• pp.1230-1236
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• 2016

This study aims to determine the effect of fly ash with a high replacing ratio of clay on the radiation shielding properties of bricks. Some interaction parameters (mass attenuation coefficients, half value layer, effective atomic number, effective electron density, and absorption efficiency) of clay fly ash bricks were measured with a NaI(Tl) detector at 661.6 keV, 1,173.2 keV, and 1,332.5 keV. For the investigation of their shielding behavior, fly ash bricks were molded using an admixture to clay. A narrow beam transmission geometry condition was used for the measurements. The measured values of these parameters were found in good agreement with the theoretical calculations. The elemental compositions of the clay fly ash bricks were analyzed by using an energy dispersive X-ray fluorescence spectrometer. At selected energies the values of the effective atomic numbers and effective electron densities showed a very modest variation with the composition of the fly ash. This seems to be due to the similarity of their elemental compositions. The obtained results were also compared with concrete, in order to study the effect of fly ash content on the radiation shielding properties of clay fly ash bricks. The clay fly ash bricks showed good shielding properties for moderate energy gamma rays. Therefore, these bricks are feasible and eco-friendly compared with traditional clay bricks used for construction.

• 분석과학
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• 제7권3호
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• pp.387-393
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• 1994

원자 흡수 분광법과 용매추출을 이용한 크롬의 정량분석 조건을 연구하였다. tertiary amine류 중 octy기를 갖는 trioctylamine(TOA)과 quaternary ammonium salt류 중 octyl기를 갖는 trioctylmethylammonium chloride(TOMAC)가 음이온 교환기로 사용되었다. 또한 첨가되는 산의 종류와 산의 농도 변화에 따라서 원자 흡수 분광기를 이용하여 흡광도를 측정하였다. TOA 사용시 염산의 농도가 0.1M에서 0.3M 사이, TOMAC 사용시 염산의 농도가 0.03M~0.1M 사이에서 최대 흡광도를 나타내었다. 산이 첨가된 MIBK에 용해된 TOA나 TOMAC와 Cr과의 mole 농도 비율이 1:1 이상이 된 것이 최대 추출 효율을 보였다. 추출과정을 검토한 결과, 본 실험에서 사용된 방법은 비슷한 다른 방법들과 비교하여 보면 크롬이 추출 효율이 좋은 것으로 판명되었다.