• Mass Spectrometry Letters
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• v.10 no.4
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• pp.108-111
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• 2019

The hydrolysis of penicillin G, carbenicillin and ampicillin in pure water at room temperature was studied by high pressure liquid chromatography electrospray ionization mass spectrometry. Hydrolysis of ampicillin did not occur under these conditions; however, penicillin G and carbenicillin were completely hydrolyzed after seven days. A short interpretation of this difference is proposed. The mass spectrometric behaviour, namely ESI response and fragmentation pathway, of hydrolyzed penicillin G and hydrolyzed carbenicillin have been also discussed.

• Electrical & Electronic Materials
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• v.9 no.9
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• pp.918-924
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• 1996

A downstream oxygen plasma is generated by capacitively coupled RF power and applied to photoresist stripping. Stripping rate (ashing rate) is measured in terms of RF power, chamber pressure, oxygen flow rate and temperature. Ashing reaction is thermally activated and depends on oxygen radical density. The ashing process is optimized to have the high ashing rate, good uniformity and minimal plasma damage using a statistical method.

• Proceedings of the Safety Management and Science Conference
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• 2009.11a
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• pp.649-657
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• 2009

The paper presents the measurement split split-plot models for saving the time and cost. The split split-plot designs developed are efficiently used to estimating the gauge R&R(Reproducibility & Repeatability) when the completely randomized design of all factors(such as high pressure and temperature) is expensive and time consuming. The models studied include three split split-plots considering the type of experimental units.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.278-283
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• 2000

The activity of catalysts obtained by self-propagating high temperature synthesis in reaction of partial methane oxidation at atmospheric pressure was investigated. Basing on the compared results of X-ray analysis and gas chromatography analysis of reaction products, the dependence of compounds formation on the phase concentrations in the studied catalyst samples was found.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.4
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• pp.433-438
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• 2020

Accurate forecasting of wind power is important for grid operation. Wind power has intermittent and nonlinear characteristics, which increases the uncertainty in wind power generation. In order to accurately predict wind power generation with high uncertainty, it is necessary to analyze the factors affecting wind power generation. In this paper, 6 factors out of 11 are selected for more accurate wind power generation forecast. These are wind speed, sine value of wind direction, cosine value of wind direction, local pressure, ground temperature, and history data of wind power generated.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.281-283
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• 1993

Aromatic nitro compounds are selectively hydrogenated to the corresponding amines in high yields at room temperature and atmospheric pressure using BER-Pd catalyst without affecting ketone, ether, ester, nitrile or chloro groups also present. Especially the nitro group in 4-nitrobenzyl alcohol, methyl 4-nitrobenzyl ether and N-N-dimethyl 4-nitrobenzylamine is selectively hydrogenated with this catalyst to give the corresponding amines without hydrogenolysis of benzylic groups. And aromatic nitro compound can be reduced selectively in the presence of aliphatic nitro compound.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.2
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• pp.225-229
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• 2011

In this study, capacitive type pressure sensors based on low temperature co-fired ceramics (LTCC) technology for environmental monitoring were demonstrated. The LTCC is one of promising technology than is based one since it has many advantages (e.g., low cost production, high manufacturing yields and easy realizing 3D structure etc.) for sensor application. Especially, it has good mechanical and chemical properties for robust environmental application. The 3D LTCC diaphragm with thickness of 400 ${\mu}m$ were fabricated by laminating 4 green sheets using commercial powder (NEG, MLS 22C). To evaluate the sensing properties of the different cavity areas, two types of diaphragm which had different cavity areas with 25, 49 $mm^2$ respectively, were fabricated. To realize capacitive type pressure sensor, the Au top electrode was fabricated using thermal evaporator and the bottome electrode was compressed using aluminium foil. The sensing properties of the fabricated sensors showed linear characteristic under different pressure (0~30 psi) using pressure measurement system.

• Journal of the Korean Ceramic Society
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• v.44 no.9
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• pp.529-535
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• 2007

Calcium oxide has been used as a demolition agent in fracturing rocks and old concrete structures, etc. With the agent, demolition work can be done in safety without a noise, vibration and any other pollution, since high expansive pressure is obtained gradually by only mixing the agents with water and pouring the slurry into boreholes. But application of the non-explosive demolition agent is a time-consuming job, especially in winter. Essentially, this problem is related to the reaction rate of calcium oxide with water. This study examines the influence of additives such as cement and anhydrite on expansion pressure of calcium oxide at different curing temperatures. The expansion pressure of calcium oxide began to increase steadily with the rise of the curing temperature. When mixing calcium oxide alone with water, blown-out shot occurred. But as additives were added to calcium oxide, the reaction of calcium oxide delayed and the expansion pressure showed gradual increment. Especially, anhydrite showed a superior delaying effect than cement on the reaction of calcium oxide.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_2
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• pp.1059-1065
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• 2020

Demand for pressure sensors is increasing in various fields such as machinery, healthcare and medical care. A recent study is being conducted to create sensors that are more sensitive and have longer linear sections based on measurement principles. In this paper, a film-type sensor with a membrane structure was developed to measure the pressure distributed in the axial direction of a hot roll laminator. Performance of sensors was evaluated by resistance and durability according to membrane diameter. The resistance of the membrane sensor varies according to the contact state and contact area of the electrode. Therefore, the membrane diameter selection is important. Experiments showed the most pronounced variation in resistance under pressure at 8 mm in diameter of membrane. Reliability evaluation of sensors was carried out at room temperature and high temperature. The pressure on the sensor was pressurized 1000 times to measure the initial resistance and the resistance after the evaluation to analyze the change. Sensors showed stable results with low resistance changes of 5.15% and 6.27%, respectively. A large area sensor manufactured using the developed sensor also showed reliable results.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3458-3463
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• 2007

Leakage would happen because of the damage of high temperature and high-pressure valve in nuclear power plant. condition based prevention maintenance is essential by using the suitable method based on local condition. Energy loss prevention can prevent from an accurate test, Local actually and ability. The methods of test for high energy fluid leakage at present are analysis of ${\Delta}$T, AE(Acoustic Emission) analysis, and thermal image. The result for test of AC (Main steam) system in YNG 2 Unit reveals that the AE occurred clearly in leakage situation, but thermal image didn't occur. It is identified that leakage is occurred when the orifice located front and back of valve operates. It shows that making a impatient judgment by using the single method if it is leakage is containing uncertainty. So I think that using the Multi-Measuring method is more sound judgment than Single-Measuring method.