• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.25-29
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• 2009

Purpose: Several radioactive agents were used for lymphoscintigraphy in breast cancer. But recently, due to the change of local radiopharmaceutical licensing policy and discontinuation of supplies from manufacturer, we could not use many radiocolloids such as $^{99m}Tc$-Antimony Trisulfide Colloid, $^{99m}Tc$-Tin Colloid, $^{99m}Tc$-Human Serum Albumin. So it is necessary to use the substitution radiopharmaceutical. Therefore, this study aims to evaluate the performance of substitution radiopharmaceutical ($^{99m}Tc$-Phytate) including the existing radiocolloids and to set up of the appropriate protocol in lymphoscintigraphy. Materials and Methods: For each radiocolloids ($^{99m}Tc$-Antimony Trisulfide Colloid (ASC), $^{99m}Tc$-Tin Colloid (TC), $^{99m}Tc$-Human Serum Albumin (HSA), $^{99m}Tc$-Phytate) were performed the particle size by Zeta Sizer (Nano-ZS) and we compared the radiolabeling time, procedure and acquisition time for each of the radiocolloids (total 200 patients). For the last time, we made an analysis of image for each of the radiocolloids with our previous report (SJ Jang et al, Korean Nucl Med Mol imaging Vol.41, No.6, Dec 2007). Results: The particle size of each radiocolloids showed A.S.C (50 nm), T.C (310 nm), H.S.A (10.8 nm), $^{99m}Tc$-Phytate (499 nm). The labeling and acquisition time for each of the radiocolloids showed no substantial difference. But there is difference of the labeling time for the A.S.C. because the ASC procedure need to boiling process. There were no significant differences among those radiocolloids (p>0.005) in the identification rate (IR), false negative rate (FNR), and negative predictive value (NPV). Conclusions: $^{99m}Tc$-labeled radiocolloids showed equivalent results in lymphoscintigraphy. Therefore, in this exam of each radiocolloids could be applied appropriate protocol in lymphoscintigraphy.

• Journal of the Korean Ceramic Society
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• v.49 no.2
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• pp.197-203
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• 2012

In this study, in order to improve densification of $La_{0.8}Ca_{0.2}Cr_{0.9}Co_{0.1}O_{3-\delta}$ (LCCC), which is known for one of the most proper candidate interconnector materials in the solid oxide fuel cells, $CaCrO_4$ was prepared via solid oxide synthesis route and added to the LCCC with different amount and particle sizes. As the amount of the $CaCrO_4$ increased, porosity of the sintered samples increased, and the pore size was proportional to the particle size of the $CaCrO_4$. This supports the fact that the $CaCrO_4$ phase forms liquid during sintering and permeate into the matrix leaving behind large pores. Then the liquid reacts with the matrix through the solid solution. However, when the samples were sintered with a slow ramp up rates, the porosity decreased. This is thought to be caused by the progressive solid solution of $CaCrO_4$ before the temperature reach to the melting temperature and forms a fluent amount of liquids. The sintering behavior of the LCCC with the addition of $CaCrO_4$ was analyzed through the transient liquid phase sintering on the basis of the microstructure observation and phase identification by x-ray diffraction.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.129-136
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• 2005

There should not be ion exchange resin particles in S/G sludge. The suspicious spherical resin particles observed in S/G sludge sample were characterized for particle size distribution under optical microscope using the micro-technique, for element analysis by the electron probe micro analysis (EPMA), and for molecular identification by the IR spectroscopy The particle sizes are distributed from 1 to 200 ${\mu}m$ for the sludge, while 40 to 500 ${\mu}m$ for the spherical resin particles. The results of the elemental analysis showed different major impurities: Si, Al, Mn, Cr, Ni, Zn and Ti for the sludge particles, while Si, Cu, Zn for the spherical resin particles. However, both particles contain Fe as a matrix of hematite ($Fe_{3}O_4$). IR spectrum of the spherical particles was quite different from that of ion exchange resins used in S/G system. These results indicate that the spherical particles are not related to ion exchange resin particles and formed by the process of the sludge formation.

• Journal of the Korean GEO-environmental Society
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• v.15 no.6
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• pp.17-29
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• 2014

A remedial investigation was conducted at five military training ranges in northern Gyeonggi province to collect information necessary for the design of on-site treatment facilities for the abatement of explosive compounds release to the environment. These information includes (i) identification of dominant explosive compounds in each range, (ii) discharge/migration routes, and (iii) contaminant distribution in particle size fraction and settling velocity of the soils. The results of investigation showed that TNT and RDX are the major contaminants but the extent of contamination varied depending on the types of military training practices and topography of the site. RDX was also detected in the subsurface soil and in the nearby stream within the training ranges, suggesting release of contaminants to streams. The median concentrations of explosives in the surface soil were less than 20 mg/kg despite several 'hot spots' in which explosives concentrations often exceeds several hundred mg/kg. The average clay contents in the soil of target area was less than 5 % compared to 12 % in the control, indicating loss of smaller particles by surface runoff during rainfall due to lack of vegetative land cover. Analysis of explosive compounds and particle size distribution showed that the amount of explosive compounds in soil particles smaller than 0.075 mm was less than 10 % of the total. Settling column tests also revealed that the quantity of explosive compounds in the liquid phase of the effluent was greater than that in the solid phase. Therefore, pre-treatment of particulate matter in surface runoff of shooting range with a simple settling basin and subsequent effluent treatment with planted constructed wetlands as polishing stage for explosives in the aqueous phase would provide the shooting ranges with a self-standing, sustainable, green solution.

• Particle and aerosol research
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• v.14 no.4
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• pp.135-144
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• 2018

Based on a two-year measurement data, major sources for the ambient carbonaceous aerosols at the Anmyeon Global Atmosphere Watch (GAW) station were identified by using the Positive Matrix Factorization (PMF) model. The particulate matter less than or equal to $2.5{\mu}m$ in aerodynamic diameter (PM2.5) aerosols were sampled between June 2015 to May 2017 and carbonaceous species including ~80 organic compounds were analyzed. When the number of factors was 5 or 6, the performance evaluation parameters showed the best results, With 6 factor case, the characteristics of transported factors were clearer. The 6 factors were identified with various analyses including chemical characteristics and air parcel movement analysis. The 6 factors with their relative contributions were (1) anthropogenic Secondary Organic Aerosols (SOA) (10.3%), (2) biogenic sources (24.8%), (3) local biomass burning (26.4%), (4) transported biomass burning (7.3%), (5) combustion related sources (12.0%), and (6) transported sources (19.2%). The air parcel movement analysis result and seasonal variation of the contribution of these factors also supported the identification of these factors. Thus, the Anmyeon Island GAW station has been affected by both regional and local sources for the carbonaceous aerosols.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.4
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• pp.431-445
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• 2022

A quantitative phase analysis method of X-ray powder diffraction was studied to determine the mineral content of clay-rich rocks practically as well as effectively. For quantitative X-ray powder diffraction analysis of the clay-rich rocks, it is necessary to prepare whole-rock powder samples with a random orientation by side mounting method. In addition, for the identification of the clay minerals in the rock, it is required to prepare an oriented mount specimen with a clay particle size of 2 ㎛ or less, ethylene glycol treatment, and heat treatment. RIR (reference intensity ratio) and Rietveld method were used for the quantitative analysis of the clay-rich rocks. It was possible to obtain the total clay and the non-clay minerals contents from the whole-rock X-ray diffraction profiles using the RIR values. In addition, it was possible to calculate the relative content of each clay mineral from the oriented X-ray diffraction profiles of the clay particle size and assign it to the total clay. In the Rietveld method of whole-rock X-ray diffraction, effective quantitative values were obtained from the Rietveld diffraction patterns excluded the region of less than 10 degrees (2θ). Similar quantitative values were shown in not only the RIR but the Rietveld methods. Therefore, the analysis results indicate a possibility of a routine quantitative analysis of clay-rich rocks in the laboratory. However, quantitative analysis of clay minerals is still a challenge because there are numerous varieties of clay minerals with different chemical and structural characteristics.

• Asian Journal of Atmospheric Environment
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• v.6 no.1
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• pp.53-66
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• 2012

A comparison of analytical approaches for Levoglucosan ($C_6H_{10}O_5$, commonly formed from the pyrolysis of carbohydrates such as cellulose) and used for a molecular marker in biomass burning is made between the four different analytical systems. 1) Spectrothermography technique as the evaluation of thermograms of carbon using Elemental Carbon & Organic Carbon Analyzer, 2) mass spectrometry technique using Gas Chromatography/mass spectrometer (GC/MS), 3) Aerosol Mass Spectrometer (AMS) for the identification of the particle size distribution and chemical composition, and 4) two dimensional Gas Chromatography with Time of Flight mass spectrometry (GC${\times}$GC-TOFMS) for defining the signature of Levoglucosan in terms of chemical analytical process. First, a Spectrothermography, which is defined as the graphical representation of the carbon, can be measured as a function of temperature during the thermal separation process and spectrothermographic analysis. GC/MS can detect mass fragment ions of Levoglucosan characterized by its base peak at m/z 60, 73 in mass fragment-grams by methylation and m/z 217, 204 by trimethylsilylderivatives (TMS-derivatives). AMS can be used to analyze the base peak at m/z 60.021, 73.029 in mass fragment-grams with a multiple-peak Gaussian curve fit algorithm. In the analysis of TMS derivatives by GC${\times}$GC-TOFMS, it can detect m/z 73 as the base ion for the identification of Levoglucosan. It can also observe m/z 217 and 204 with existence of m/z 333. Although the ratios of m/z 217 and m/z 204 to the base ion (m/z 73) in the mass spectrum of GC${\times}$GC-TOFMS lower than those of GC/MS, Levoglucosan can be separated and characterized from D (-) +Ribose in the mixture of sugar compounds. At last, the environmental significance of Levoglucosan will be discussed with respect to the health effect to offer important opportunities for clinical and potential epidemiological research for reducing incidence of cardiovascular and respiratory diseases.

• Analytical Science and Technology
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• v.26 no.4
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• pp.245-255
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• 2013

Identification of paint on victim's clothing and a vehicle are valuable for forensic examination when investigating hit-and-run accidents. Automotive paints on clothes are used to prove a victim caused by traffic accident and to identify a suspected vehicle. The comparison of transferred paints between victim's vehicle and suspected vehicle can be an important evidence in reconstructing the accident situation and in discovering the truth. The paints such as white, yellow, red, blue, or black are hard to examine particle shape under a stereomicroscope because of it is not included aluminum, pearl, and mica flakes in the pigments. The aim of this study under forensic aspect is to compare pigment among basecoat layers of solid paints by identifying inorganic elemental compositions and binder resins of pigments using by micro-FT-IR and micro-XRF spectrometer. The pigment samples were analyzed by using two methods of FT-IR: Reflectance and ATR method. Two methods of FT-IR were useful in discriminating binder resins of pigments by comparing characteristic peaks and patterns of spectra. Also, XRF spectrometer could identify the elemental compositions in inorganic pigments of trace paints which are difficult to compare the identification by FT-IR.

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.181-187
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• 2013

Identification of main ingredients in starches has been investigated using physicochemical analysis method mainly. However, physicochemical properties such as particle size have limitations in determining the differences among mixed starches. Therefore, we developed a molecular biological method to identify materials used in starch, as a sample, 11 kinds of starches including sweet potato starch, potato starch, corn starch, and tapioca starch. DNeasy plant mini kit, magnetic DNA purification system, and CTAB methods were used to extract DNA from samples. After gene extraction, whole genome amplification (WGA) was performed to amplify the extracted DNA. Species-specific primers were used as followings: ib-286-F/ib-286-R (105 bp), Pss 01n-5'/Pss 01n-3' (216 bp), SS11b 3-5'/SS11b 3-3' (114 bp), and SSRY26-F/SSRY26-R (121 bp) gene for sweet potato, potato, corn, and tapioca, respectively. In this study, we could confirm the main ingredients using WGA and PCR method.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.E
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• pp.19-27
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• 2000

Particle Induced X-ray Emission (PIXE) and Elemental Analysis Syztem (EAS) were applied to the investiga-tion of the Characteristics and sources of wintertime atmospheric aerosols in Seoul. Atmospheric aerosols were collected by both fine and coarse fractions using a two-stage filter pack sampler from Kon-Kuk university during the winter season of 1999. PIXE was applied to the analysis of the middle and heavy elements with atomic numbers greater than 14(Si) and EAS was applied to the measurement of the light elements such as H, C and N. The fact that 64.2% of mass of fine particles in Seoul consists of the light elements (N, C , and H) suggests that the measurement of light elements is extremely important. The average mass concentration is Seoul was 38.6$\mu\textrm{g}$m(sup)-3. Elements such as Ca, Fe, Mg, and Ti appeared to have very low Fine/Coarse ratios(0.1∼0.4), whereas che-mical components related to anthropogenic sources such as Br, V, Pb, and Zn were observed to accumulate in the fine fraction. In the Asian Dust Storm(ADS) event, the concentation of soil components increased dramatically. Reconstruction of the fine mass concentrations estimated by a newly revised simple model was fairly in good agreement with the measured ones. Source identification was attempted using the enrichment factor and Pearsons coefficient of correlation. The typical elements derived from each source could be classified by this method.