• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.150-150
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• 2008

본 연구에서는 Wet chemistry damage가 Nanopatterned p-ohmic electrode에 미치는 영향을 연구하였다. Nanopattern은 Metal clustering을 이용하여, P-GaN와 Ohmic형성에 유리한 Pd을 50$\AA$ 적층한 후 Rapid Thermal Annealing방법으로 $850^{\circ}C$, $N_2$분위기에서 3min열처리를 하여 Pd Clustering mask 를 제작하였다. Wet etching은 $85^{\circ}C$, $H_3PO_4$조건에서 시간에 따라 Sample을 Dipping하는 방법으로 시행하였다 Ohmic test를 위해서 Circular - Transmission line Model 방법을 이용하였으며, Atomic Force Microscopy과 Parameter Analyzer로 Nanopatterned GaN surface위에 형성된 Ni/ Au Contact에서의 전기적 분석과, 표면구조분석을 시행하였다. AFM결과 Wet처리시간에 따라서 Etching형상 및 Etch rate이 영향을 받는 것이 확인되었고, Ohmic test에서 Wet chemistry처리에 의한 Tunneling parameter와 Schottky Barrier Height가 크게 증/감함을 관찰하였다. 이러한 결과들은 Wet처리에 의해서 발생된 Defect가 GaN의 표면과 하부에서 발생되며, Deep acceptor trap 및 transfer거동과 밀접한 관련이 있음을 확인 할 수 있었다. 보다 자세한 Transport 및 Wet chemical처리영향에 관한 형성 Mechanism은 후에 I-V-T, I-V, C-V, AFM결과 들을 활용하여 발표할 예정이다.

• Journal of Acupuncture & Meridian Studies
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• v.11 no.6
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• pp.375-379
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• 2018

Background and aim: Heavy metals have been recognized as toxins for centuries. Cupping therapy has been shown to aid in the excretion of accumulated fluids and toxins from the interstitial fluid. The aim of this study was to investigate the effects of wet cupping therapy on blood levels of heavy metals. Methods: Thirteen healthy male individuals [mean age ${\pm}$ standard deviation, $28.47{\pm}6.18$] participated in this study. Venous blood samples were collected 5 min before and 30 days after the wet cupping therapy. Five points of the posterior neck and bilateral perispinal areas of the neck and thoracic spine were selected for cupping therapy. The levels of aluminium (Al), zinc (Zn), and cadmium (Cd) were measured using an atomic absorption spectrophotometer. Results: The levels of heavy metals (Al, Zn, and Cd) after cupping therapy were significantly lower than the levels before therapy. Conclusions: These results suggest that wet cupping therapy has an excretory effect on the kidney. Wet cupping therapy may clear blood from excess heavy metals.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.130-139
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• 1999

In order to manage the wet end chemistry on paper machines, our goal is to control sub-processes through which we can influence the entire wet end operations with maximum effect. The most important sub-processes are: consistency, ash, and chemistry. The management of these three main groups is based on on-line maesurements and automatic control. This paper presents a new wet end management platform, a new analyzer. This new analyzer utilizes a modular structure and modem software. It is part of a new paper machine concept. The controls of this concept are feedback and feedforward solutions that control retention, consistencies, ash, and charge, resulting in a more stable wet end (30...80%), more uniform paper, and better rnnability.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.3095-3097
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• 2009

• The Korean Journal of Ecology
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• v.25 no.6
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• pp.383-389
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• 2002

Pb and Cd concentrations and reproductive progress of feral pigeons were investigated in urban (Seoul) and industrial complex (Ansan) areas from November 2000 to May 2001. Results of the Pb analysis for the feral pigeons from the Ansan industrial complex (egg contents: 1.13 $\mu$g/wet g, bones of adult: 10.5 $\mu$g/wet g) and Seoul (1.64 $\mu$g/wet g, 29.5 $\mu$g/wet g, respectively) indicated that the Pb level of eggs and bones of adults were significantly different between the two colonies (p<0.05). Cd concentrations in liver and kidney of adult pigeons were also significantly different between the Ansan (liver: 0.14 $\mu\textrm{g}$/wet g, kidney: 0.43 $\mu$g/wet g) and Seoul (liver. 0.24 $\mu$g/wet g, kidney: 1.05 $\mu$g/wet g) colonies. (p<0.05). However, egg size and thickness, incubation period and nestling growth rates did not differ between the study areas. Also, clutch size, number of young hatched per nest and number of young fledglings per nest did not significantly different in the noted areas. Considering the lead and cadmium concentrations of pigeons, these were not as high as those considered as results in toxic effects in other species, and the biological significance from these level differences is uncertain.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.842-845
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• 2011

Wet air oxidation (WAO) of oily sludge was carried out using $Fe^{3+}$ as catalyst, placed in a 0.5 L batch autoclave in the temperature range of $250-330^{\circ}C$. Experiments were conducted to investigate the effects of temperature, the initial COD, reaction time, concentration of catalyst and $O_2$ excess (OE) on the oxidation of the oily sludge. The results showed that in the WAO 88.4% COD was achieved after 9 min reaction at temperature of $330^{\circ}C$, OE of 0.8 and the initial COD of 20000 mg/L. Temperature was found to have a significant impact on the oxidation of oily sludge. Adding a catalyst significantly improved the COD removal. Homogenous catalyst, $Fe^{3+}$, showed effective removal for pollutants. COD removal was 99.7% in the catalytic wet air oxidation (CWAO) over $Fe^{3+}$ catalyst. The results proved that the CWAO was an effective pretreatment method for the oily sludge.

• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.1021-1022
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• 2003

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.3
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• pp.163-167
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• 1989

Near infrared reflectance spectroscopy (NIRS) analysis of commercial farm alfalfa hay for crude prowin (CP), neutral detergent fiber(NDF), and acid detergent fiber(ADF) was compared with wet chemistry results. There were no differences between NIRS and wet chemistry results in CP and ADF content, but there were differences (P <.05) between NIRS and wet chemistry results for sample No.2, 4, 5 in NDF content.

• Journal of Food Hygiene and Safety
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• v.33 no.1
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• pp.83-88
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• 2018

The purpose of this study was to investigate and evaluate the safety of the wet tissues. In this study, we analyzed sterilizing preservatives and the presence of harmful substances in 62 wet tissue samples in the market. The contents of preservatives, formaldehyde and methanol were analyzed by HPLC and headspace-GC, respectively. Cetylpyridinium chloride was detected as 7-13 ppm in 5 samples. Sodium benzoate was detected in 46 samples ranging from 200 ppm to 3500 ppm, and 9 ppm of methylparahydroxy benzoate was detected in 1 sample. Propylparahydroxy benzoate was not detected in any samples. 5 ppm of methylchloroisothiazolinone and 140 ppm of methylisothiazolinone were detected in 1 sample. Formaldehyde was detected as $0.0069-1.796{\mu}g/g$ in 59 samples. Methanol was detected ranging from 2 ppm to 51 ppm in 22 samples, and 4 samples showed more than 20 ppm of the legal limit. The pH of the wet tissues was 4.0 to 8.2. Continuous investigation and monitoring are necessary to ensure safe distribution of products.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.68-71
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• 2014

Petroleum refining unavoidably generates large volumes of oily wastewater. The environmentally acceptable disposal of oily wastewater is a current challenge to the petroleum industry. Nowadays, more attentions have been focused on the treatment techniques of oily wastewater. Oily wastewater contained highly concentrated and toxic organic compounds. Wet peroxide oxidation (WPO) and catalytic wet oxidation (CWO) were applied to eliminate pollutants to examine the feasibility of the WPO/CWO of oily wastewater. The results indicated that more than 80% chemical oxygen demand (COD) removal from oily wastewater was achieved with CWO. Homogenous catalyst, $NaHCO_3$ and $Na_2CO_3$ and NaOH showed effective removal for pollutants in oily wastewater. Greater than 90% COD removal was achieved with WPO. It was concluded that WPO was a far more effective process for oily wastewater.