• Korean Journal of Materials Research
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• v.9 no.3
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• pp.244-250
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• 1999

MOCVD TiN films were prepared from a new TiN precursor, tetrakis(etylmethylamino)titanium (TEMAT) and ammonia. Deposition of TiN films from a single precursor, TEMA T yielded the growth rates of $70 to 1050\AA$/min, depending on the deposition temperature. Furthermore, the excellent bottom coverage of -90% over $0.35\mu\textrm{m}$ contacts was obtained at $275^{\circ}C$. The addition of ammonia to TEMA T lowered the resistivity of as- deposited TiN film to ~ $800\mu\omega-cm$ from $3500~6000\mu\omega-cm$ and improved the stability of TiN film in air. Examination of the films by Auger electron spectroscopy(AES) showed that the oxygen and carbon contents decreased with the addition of ammonia. However, increasing ammonia flow rate decreased the bottom coverage of TiN films over $0.5\mu\textrm{m}$ contacts, probably due to the high sticking coefficient of intermediate species produced from the gas phase reaction of TEMA T and ammonia. Based on the byproduct gases detected by the quadrupole mass spectrometer (QMS), the transammination reaction was proposed to be responsible for TiN deposition. In addition, XPS analysis revealed that the carbon in the films made from TEMA T and ammonia was metallic carbon, suggesting that $\beta$-hydrogen activation process occurs competitively with the transammination reaction.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1442-1445
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• 2000

This study was carried out to investigate the contents of minerals and heavy metals in the sea salts of Korean products and imported products. NaCl was major component, which ranged from $80.31{\sim}89.84%$ for Korean products and from $91.59{\sim}97.66%$ for imported products. Minerals and heavy metals of Korean products and imported products were analyzed with ICP-AES and AAS, respectively. Mineral contents of K and Mg in Korean products were relatively higher than those in imported ones, but no significant differences were found for heavy metals between them.

• Resources Recycling
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• v.26 no.4
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• pp.50-55
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• 2017

Determination of trace elements in a sample including complicated matrix is very difficult due to the interference by the matrix. Therefore, if the trace elements can be separated from the complex sample matrix and determined, the interference effects can be reduced, and it is very helpful for the overall analysis. In this study, the analytes of trace elements were separated from the sample matrix by co-precipitation with trace elements using indium hydroxide ($In(OH)_3$), then detected by inductively coupled plasma-atomic emission spectrometer (ICP-AES). Above all, the optimal conditions for the co-precipitation of elements with indium hydroxide were experimentally established. At last, salt was analyzed by the developed analytical method. No heavy metals were not found in Shinan Jeungdo salt, but trace amounts of several heavy metals except for cadmium were found in Cheonnam Yongkwang salt.

• Korean Journal of Materials Research
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• v.4 no.5
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• pp.550-555
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• 1994

The effects of RTA treatment on the leakage current have been studied for tantalum pentoxide( $Ta_2O_5$) films deposited by PECVD on P-type(100) Si substrate using $TaCl_5$(99.99%) and $N_2O$(99.99%) gaseous mixture. The refractive index increased with increasing the deposition temperature and the maximum deposition rate was obtained at $500^{\circ}C$. The Ta-0 bond peak intensity of as-deposited $Ta_2O_5$ increased with increasing the deposition temperature through FT-IR analysis and the leakage current value was decreased with increasing the deposition temperature. The small leakage current value obtained after RTA treatment of as-deposited $Ta_2O_5$ was found to be due to the reduction of 0-deficient structure in the film. The increases of the oxygen coacentration and the Ta-0 bond peak intensity in the film after RTA treatment were measured by AES and FT-IR analyses.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.255-260
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• 2011

$NH_4{^+}-{\beta}^{{\prime}{\prime}}$-alumina which is expected to an inorganic solid electrolyte of high temperature polymer electrolyte membrane fuel cells (PEMFC) was prepared by ion-exchange reaction of $K^{+}-{\beta}^{{\prime}{\prime}}$-alumina pellet with $NH_4NO_3$ aqueous solution and molten $NH_4NO_3$ salts as an ion-exchange medium in the autoclave and the heating mentle reaction. In the autoclave reaction, the concentrations of $NH_4NO_3$ solution was chosen at 5 and 10 M. Each ion-exchange reaction was carried out at 130, 150, 170, and $200^{\circ}C$ for 2, 4, 6 and 8 h. In the heating mentle reaction, ion-exchange was performed at $200^{\circ}C$ for 2, 4, 6 and 8 h with molten $NH_4NO_3$ salts. In order to determine the effect of reaction times, each ion-exchange reaction was repeated 3 times. The phase stability and the ion-exchange rate of $NH_4{^+}-{\beta}^{{\prime}{\prime}}$-alumina were analyzed by XRD and ICP.

• Clean Technology
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• v.26 no.4
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• pp.270-278
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• 2020

Palladium (Pd) has been widely used in various industrial applications such as jewelry, catalyst, and dental materials despite its limited resources. It has been gaining attention to recover Pd with high purity from the spent materials. This study investigated the optimum conditions for the leaching and recovery of metallic Pd. The leaching parameters are HCl concentration, temperature, time, concentration of oxidants, and pulp density. 97.2% of Pd leaching efficiency was obtained in 3 M HCl with 3 vol% oxidants at 80℃ for 60 min. The ratio of hydrogen peroxide to sodium hypochlorite played a critical role in the leaching efficiency due to the supply of Cl- ions in the leachate. Moreover, the complete recovery of Pd in the leachate was achieved at 80℃ with 0.3 formic acid/leachate after adjusting the pH value of 7. This situation was ascribed to the decomposition of formic acid into hydrogen gas and carbon dioxide at 80℃. ICP-AES and XRD characterized the recovered Pd powder, and the purity of the recovered powder was found to be 99.6%. Consequently, the recovered Pd powder with high purity could be used in circuits, catalyst precursors, and surgical instruments.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.5
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• pp.987-995
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• 2022

Deep learning-based profiling side-channel analysis has been many proposed. Deep learning-based profiling analysis is a technique that trains the relationship between the side-channel information and the intermediate values to the neural network, then finds the secret key of the attack device using the trained neural network. Recently, cross-device profiling side channel analysis was proposed to consider the realistic deep learning-based profiling side channel analysis scenarios. However, it has a limitation in that attack performance is lowered if the profiling device and the attack device have not the same chips. In this paper, an environment in which the profiling device and the attack device have not the same chips is defined as the different-device, and a novel deep learning-based profiling side-channel analysis on different-device is proposed. Also, MCNN is used to well extract the characteristic of each data. We experimented with the six different boards to verify the attack performance of the proposed method; as a result, when the proposed method was used, the minimum number of attack traces was reduced by up to 25 times compared to without the proposed method.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.13-20
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• 2009

Objectives: To compare the contents of hazardous substances before/after a decoction. Methods : The heavy metal contents before/after a decoction were measured by Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) and mercury analyzer. In order to analyze pesticides in 6 samples we used simultaneous multi-residue analysis of pesticides by GC/ECD, which was followed by GC/MSD analysis to confirm the identity of the detected pesticide in each sample. In addition, the contents of sulfur dioxide (S02) were performed by Monier-Williams distillation method. Results : 1. The mean values of heavy metal contents (mg/kg) for the samples were as follows: Socheongryong-tang (before decoction - Pb; 1.115, Cd; 0.179, As; 0.069 and Hg; 0.028, after decoction - Pb; 0.110, Cd; 0.011, As; 0.005 and Hg; 0.002), Insampaedok-san (before decoction - Pb; 1.207, Cd; 0.148, As; 0.171 and Hg; 0.026, after decoction - Pb; 0.075, Cd; 0.006, As; not detected and Hg; O.OOD, Oryung-san (before decoction - Pb; 1.955, Cd; 0.430, As; 0.063 and Hg; 0.027, after decoction - Pb; 0.083, Cd; 0.013, As; 0.006 and Hg; 0.002), Hwangryunhaedok-tang (before decoction - Pb; 1.825, Cd; 0.210, As; 0.050 and Hg; 0.009, after decoction - Pb; 0.107, Cd; 0.010, As; 0.005 and Hg; O.OOD, Bangpungtongseong-san (before decoction - Pb; 1.740, Cd; 0.162, As; 0.585 and Hg; 0.018, after decoction - Pb; 0.041, Cd; 0.006, As; 0.022 and Hg; not detected) and Oyaksungi-san (before decoction - Pb; 1.199, Cd; 0.183, As; 0.321 and Hg; 0.031, after decoction - Pb; 0.096, Cd; 0.008, As; 0.021 and Hg; 0.0004). 2. Contents (mg/kg) of sulfur dioxide (S0$_2$) before a decoction in Socheongryong-tang, Insampaedok-san, Oryung-san, Hwangryunhaedok-tang, Bangpungtongseong-san and Oyaksungi-san exhibited 3.2, 5.7, 4.5, 49.8, 7.8 and 22.4, respectively. However, contents of sulfur dioxide after a decoction in all samples were not detected. 3. Contents (mg/kg) of residual pesticides before/after a decoction in all samples were not detected. Conclusions : These results will be used to establish a criterion of heavy metals, residual pesticides and sulfur dioxide.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.111-119
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• 2009

Objectives : To compare the contents of hazardous substances before/after a decoction. Methods : The heavy metal contents before/after a decoction were measured by Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) and mercury analyzer. In order to analyze pesticides in 6 samples we used simultaneous multi-residue analysis of pesticides by GC/ECD, which was followed by GC/MSD analysis to confirm the identity of the detected pesticide in each sample. In addition, the contents of sulfur dioxide (SO2) were performed by Monier-Williams distillation method. Results : 1. The mean values of heavy metal contents (mg/kg) for the samples were as follows: Samchulkunbi-tang (before decoction - Pb; 1.592, Cd; 0.155, As; 0.055 and Hg; 0.014, after decoction - Pb; 0.036, Cd; 0.002, As; not detected and Hg; 0.001), Yijin-tang (before decoction - Pb; 0.830, Cd; 0.077, As; 0.045 and Hg; 0.015, after decoction - Pb; 0.193, Cd; 0.010, As; not detected and Hg; 0.002), Banhabaikchulcheunma-tang (before decoction - Pb; 0.976, Cd; 0.164, As; 0.167 and Hg; 0.019, after decoction - Pb; 0.031, Cd; 0.003, As; 0.006 and Hg; 0.005), Pyungwi-san (before decoction - Pb; 2.162, Cd; 0.128, As; 0.061 and Hg; 0.018, after decoction - Pb; 0.080, Cd; 0.006, As; not detected and Hg; 0.005), Leejung-tang (before decoction - Pb; 1.480, Cd; 0.294, As; 0.034 and Hg; 0.012, after decoction - Pb; 0.064, Cd; 0.007, As; 0.007 and Hg; 0.002) and Kwibi-tang (before decoction - Pb; 0.907, Cd; 0.193, As; 0.085 and Hg; 0.020, after decoction - Pb; 0.072, Cd; 0.006, As; 0.004 and Hg; 0.002). 2. Contents (mg/kg) of sulfur dioxide ($SO_2$) before a decoction in Banhabaikchulcheunma-tang, Pyungwi-san, Leejung-tang and Kwibi-tang exhibited 3.5, 3.4, 3.8 and 12.4, respectively. However, contents of sulfur dioxide after a decoction in all samples were not detected. 3. Contents (mg/kg) of residual pesticides before/after a decoction in all samples were not detected. Conclusions : These results will be used to establish a criterion of heavy metals, residual pesticides and sulfur dioxide.

• Analytical Science and Technology
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• v.37 no.3
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• pp.155-165
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• 2024

This study aimed to assess whether plant-based meat substitutes can effectively replace animal meat products in terms of amino acid composition and zinc bioavailability. The evaluation was conducted in response to the growing demand for meat substitutes, driven by the increasing vegan population and the expansion of vegan culture. For this purpose, a chicken product and two plant-based meat substitutes in tender form were selected. The amino acid content and composition were measured using HPLC, while the levels of trace elements like zinc and calcium were determined through ICP-AES. Additionally, the presence of phytic acid, which inhibits zinc bioavailability, was extracted and quantified using UV-Vis spectroscopy. The results were analyzed in the context of daily product consumption. The findings revealed that certain essential amino acids, such as valine and lysine, were found to be deficient in plant-based meat substitutes compared to animal meat products. It was challenging to meet the recommended daily intake of these amino acids solely through the use of meat substitutes. Regarding zinc bioavailability, the inhibitory effect of calcium on zinc bioavailability was expected to be minimal. The zinc bioavailability of the meat substitutes varied significantly depending on the zinc and phytic acid content of the ingredients. Therefore, ingredients of plant-based meat substitutes should be carefully modulated to reach appropriate zinc bioavailability by selecting and processing plant materials with high zinc and low phytic acid content.