• Journal of Powder Materials
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• v.15 no.3
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• pp.221-226
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• 2008

Silver coated copper composite powders were prepared by electroless plating method by controlling the activation and deposition process variables such as feeding rate of silver ions solution, concentration of reductant and molar ratio of activation solution $(NH_4OH/(NH_4)_2SO_4)$ at room temperature. The characteristics of the product were verified by using a scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic absorption (A.A.). It is noted that completely cleansing the copper oxide layers and protecting the copper particles surface from hydrolysis were important to obtain high quality Ag-Cu composite powders. The optimum conditions of Ag-Cu composite powder synthesis were $NH_4OH/(NH_4)_2SO_4$ molar ratio 4, concentration of reductant 15g/l and feeding rate of silver ions solution 2 ml/min.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.3
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• pp.228-239
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• 2022

Purpose: To compare the effectiveness, tolerability, acceptability, and safety of sodium picosulphate with magnesium citrate (PS/Mg) and polyethylene glycol (PEG) in children (≤18 years) preparing for colonoscopy. Methods: Three electronic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials) were searched till July 2020. Only randomized controlled trials (RCTs) were included. At least two authors independently selected studies and performed risk of bias assessment and data extraction. Results: Four RCTs (n=390), with overall good quality were included. A meta-analysis of two trials (n=224) found no statistically significant difference between the groups with respect to the proportion of patients who had excellent and good scores (≥6 points) according to the Boston Bowel Preparation Scale (relative risk: 0.99; 95% confidence interval [CI]: 0.90 to 1.08). Excellent and good scores were observed in both groups in approximately 90% of children. A meta-analysis of two other trials (n=150) showed no significant difference between the groups with respect to the mean total score for the Ottawa Bowel Preparation Scale (mean difference: 0.20; 95% CI: -0.74 to 1.14). Both regimens provided a comparable safety profile; however, PS/Mg was significantly superior to high volume PEG in terms of tolerability (abdominal pain, nausea, vomiting, bloating/flatulence/fullness) and acceptability (ease of formulation consumption, taste acceptance, need for nasogastric tube, compliance with full dose). Conclusion: PS/Mg provides a quality and safety profile similar to PEG for bowel cleansing; however, it has better acceptance and tolerance in children preparing for colonoscopy.

• Journal of the Korean Vacuum Society
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• v.18 no.5
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• pp.372-376
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• 2009

In the modern semiconductor industry, lithography process is used to construct specific patterns. However, due to the decreasing of line width, these days, more and more researchers are interested in PMMA(Poly Methyl Methacrylate) lithography by using e-beam instead of the prior method, PR(Photoresist) lithography by using UV(Ultra-Violet). Additionally, the patterns constructed by lithography are collapsed during the process of cleansing remnants and the resistance against the breakdown of the patterns is known to be proportional to the elastic modulus of pattern-constructing materials. In this research, we measured the change of hardness and elastic modulus of PMMA film surface according to the change of time spent to soft-bake the PMMA film. During the measurement, we controlled the tip pressure from $25{\mu}N$ to $8,500{\mu}N$ having intervals that are $134.52{\mu}N$. For these measurements, we used the Triboindenter from Hysitron to gauge the hardness and elastic modulus and the tip we used was Berkovich diamond Tip.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.196-205
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• 2016

The exhaust gas discharged by cars not only threatens the health of the human body, but also contributes to global warming, due to the resulting increase in the concentrations of ozone, fine dust and carbon dioxide. Therefore, the government has steadily implemented careful inspection systems for exhaust emissions, in order to efficiently regulate the exhaust gas of cars. Studies on reducing the exhaust emissions of automobiles have been conducted in various fields, including ones designed to reduce the generation of HC, NOx, and $CO_2$ in the exhaust emission of vehicles. However, there have been insufficient studies on the reduction of the exhaust emission for old diesel vehicles. To develop careful inspection systems for the exhaust emissions of old diesel vehicles, studies on the reduction of the exhaust emissions and improvement of power are necessary by cleaning the carbon sediment in both the intake manifold and injector. Therefore, in this study, we analyzed and compared the amounts of gas emitted when simultaneously cleaning or not cleaning the intake manifold and injector of diesel automobiles with mileages over 80,000 km and operating periods over 5 years. The experimental results showed that in the case where the intake manifold and injector were simultaneously cleaned, there was a decline of 75.2% in the gas emission compared to the cases where only the manifold or injector is cleaned. Also, it was found that simultaneously cleansing the intake manifold and injector enabled the exhaust standard to be satisfied for less than 30% within 8.5 sec.