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Jong-Goo?KimEmail author Yang-Soon?Park Yeong-Keong?Ha Kyuseok?Song 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):723-728
The applicability of ATR-FTIR for the determination of the HDO content in heavy water (D2O) was investigated. Two groups of calibration standard solutions, of low contents (0–1 n% H2O in heavy water) and of higher contents (0–10 n% H2O in heavy water) were prepared by adding properly calculated amount of H2O to D2O by weight. The absorbances at 3400 cm−1 (ν, O–H) against the calibration standards were measured five times using two kinds of interchangeable IREs (1 bound and
9 bound reflections). And four calibration curves were obtained by linear least square fit of the measured absorbances for
the four different measurement conditions, which are (1) for low contents group using 1 bound reflection, (2) for low contents
group using 9 bound reflections, (3) for higher contents group using 1 bound reflection, (4) for higher contents group using
9 bound reflections. Determined contents (c
0) of each calibration standards for the four measurement conditions were obtained by the calibration curves and compared to
the calculated contents (c
cal). The uncertainty sources were considered when the HDO in heavy water is determined according to the procedure of this work.
The uncertainties u(c
0) of the determined contents (c
0) for the four different measurement conditions were calculated. 相似文献
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Yong Suk Choi Jong-Yun Kim Suk Bon Yoon Kyuseok Song Young Jin Kim 《Microchemical Journal》2011,99(2):332-338
A wavelength-dispersive X-ray fluorescence (WDXRF) technique that uses the scattered radiation of the X-ray tube lines and the fluorescence radiation of an element present in a powder sample is proposed as a non-destructive method for the determination of the water content in silica powder. Although direct X-ray fluorescence analysis of water using WDXRF is not adequate for the quantitative determination of water in powder, due to the very low fluorescence yield for hydrogen and oxygen, the fluorescence signal of silicon (Si) in silica powder is attenuated by water, and is shown to decrease in proportion to the water content in silica powder. In addition, it is demonstrated that the Compton- and Rayleigh-scattering of the X-ray tube lines is proportional to the water content. The coefficients of determination, R2, of the linear regression equations obtained from the calibration curves for all individual scattered radiations and for the fluorescence radiation of Si were > 0.90. The sum of the peak intensities of the four scattering signals, i.e. the Rayleigh-scattered Rh K–L2,3 and Rh K–M2,3 lines, and Compton-scattered Rh K–L2,3 and Rh K–M2,3 lines, also showed fairly good linearity and sensitivity over a very wide range of water content from 0 wt.% to 61.5 wt.%. However, porosity had a significant effect on the X-ray signal at low water content, in the range from 0 wt.% to 7.5 wt.%, where the sensitivity for the silica nanopowder with well-defined mesopores (~ 3 nm in diameter) decreased to 0.40 kcps/wt.%, from 0.99 kcps/wt.% for the non-porous silica nanopowder. The use of the Si fluorescence signal along with the scattered radiation of the X-ray tube lines expands the applicability of conventional XRF spectrometers to the quantitative determination of water content in silica powder. 相似文献
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Kristo Michael J. Williams Ross Gaffney Amy M. Kayzar-Boggs Theresa M. Schorzman Kerri C. Lagerkvist Petra Vesterlund Anna Ramebäck Henrik Nelwamondo Aubrey N. Kotze Deon Song Kyuseok Lim Sang Ho Han Sun-Ho Lee Chi-Gyu Okubo Ayako Maloubier Didier Cardona Danièle Samuleev Pavel Dimayuga Ike Varga Zsolt Wallenius Maria Mayer Klaus Loi Elaine Keegan Elizabeth Harrison Jennifer Thiruvoth Sangeeth Stanley Floyd E. Spencer Khal J. Tandon Lav 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):425-434
Journal of Radioanalytical and Nuclear Chemistry - In a recent international exercise, 10 international nuclear forensics laboratories successfully performed radiochronometry on three low enriched... 相似文献
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Young Hwan Cho Tack-Jin Kim Sang Eun Bae Yong Joon Park Hong Joo Ahn Kyuseok Song 《Microchemical Journal》2010,96(2):344-347
We have measured the electronic absorption spectra of the U(III) ion in LiCl–KCl eutectic melt at 450 °C to understand its chemical behavior in the context of pyrochemical process of spent nuclear fuel. The UV–VIS spectra of the U(III) ion consist of two main peaks in the range of 400–600 nm which are attributable to the 5f3–5f26d1 transitions. With the aid of UV–VIS spectroscopic tool, in-situ measurement of chemical reactions of the U(III) with oxide ion as well as neodymium oxide was successfully achieved. The U(III) ion forms insoluble uranium oxide phases by reacting with oxide ion and lanthanide oxides. 相似文献
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Ho Doris M. L. Nelwamondo Aubrey N. Okubo Ayako Ramebäck Henrik Song Kyuseok Han Sun Ho Hancke Jacobus J. Holmgren Stina Jonsson Sofia Kataoka Osamu Lagerkvist Petra Lee Chi-Gyu Lim Sang Ho Park Jinkyu Park Jong-Ho Pong Boon Kin Sandström Björn Shinohara Nobuo Tan Angela H. J. Toda Nobufumi Tovedal Annika Vesterlund Anna 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):353-363
Journal of Radioanalytical and Nuclear Chemistry - The Fourth Collaborative Material Exercise (CMX-4) of the Nuclear Forensics International Technical Working Group (ITWG) registered the largest... 相似文献
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Myung Ho Lee Euo Chang Jung Kyuseok Song Yun Hee Han Hyun Sang Shin 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):639-645
This work investigates the sorption of americium [Am(III)] onto kaolinite and the influence of humic acid (HA) as a function
of pH (3–11). It has been studied by batch experiments (V/m = 250:1 mL/g, C
Am(III) = 1 × 10−5 mol/L, C
HA = 50 mg/L). Results showed that the Am(III) sorption onto the kaolinite in the absence of HA was typical, showing increases
with pH and a distinct adsorption edge at pH 3–5. However in the presence of HA, Am sorption to kaolinite was significantly
affected. HA was shown to enhance Am sorption in the acidic pH range (pH 3–4) due to the formation of additional binding sites
for Am coming from HA adsorbed onto kaolinite surface, but reduce Am sorption in the intermediate and high pH above 6 due
to the formation of aqueous Am-humate complexes. The results on the ternary interaction of kaolinite–Am–HA are compared with
those on the binary system of kaolinite–HA and kaolinite–Am and adsorption mechanism with pH are discussed. Effect of different
molecular weight of HA, with three HA fractions separated by ultrafiltration techniques, on the Am sorption to kaolinite were
also studied. The results showed that the enhancement of the sorption of Am onto kaolinite at the acidic pH conditions (pH
3–4) was higher with HA fractions of higher molecular weight. Also, the Am sorption over a pH range from 6 to 10 decreased
with decreasing molecular weight of HA. 相似文献
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Kyuseok Song Seokwon Oh Euo Chang Jung Deokhyun Kim Hyungki Cha 《Microchemical Journal》2005,80(2):113
Laser photoacoustic (PA) spectroscopy is applied for the determination of the trace content of water vapor using a differential Helmholtz resonant (DHR) cell and a narrow bandwidth diode laser operating near 1380 nm. The PA spectroscopy revealed a rich absorption spectra in this wavelength region and the observed result was compared with the HITRAN database. A multipass optical system was also developed by adopting one aluminum-coated flat mirror with a small uncoated spot for the laser introduction to the detection chamber and one aluminum-coated concave mirror. The multipass optical system enabled the enhancement of the PA signal up to eight times when compared to the single pass case. The calibration curve was plotted by measuring PA signals for various pressures of the water vapor. The sensitivity of the PA detection system is estimated as 7.3×1012 molecules cm−3 with a signal-to-noise ratio (SNR) of 1. 相似文献
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Hong-Joo Ahn Myung-Ho Lee Se-Chul Sohn Kwang Yong Jee Kyuseok Song 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):199-205
In order to evaluate radionuclide inventories as an essential item for the permanent disposal of spent fuel storage racks,
chemical conditions for a sample pretreatment of a spent fuel storage rack were studied. Especially, the surface microstructure
and the radionuclide distributions for the spent fuel storage rack were investigated by using a SEM–EDX and γ-spectrometer
for minimizing the matrix effect which could affect a chemical separation process of some β-emitting radionuclides. The samples
were pretreated with a mixed solution of 5 M HCl and 2 M HNO3 by an ultrasonic surface leaching method. Some radionuclides in the raw racks showed the radioactivity of 102–103 Bq for about 10 g of sample weight. From the sample pretreatment, it was confirmed that almost all radionuclides in the rack
were completely extracted from the rack when the dissolved thickness of the rack became a maximum 15 μm by the ultrasonic
surface leaching method. The established pretreatment method was applied for all spent fuel storage rack generated from Korean
NPPs to determine the scaling factor. The radioactivities of 60Co and 137Cs radionuclides in the pretreated solutions were in the range of 4.9E−1~1.5E+2 and 1.2E−1~9.0E+0 Bq/g, respectively. 相似文献