• Journal of Energy Engineering
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• v.5 no.1
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• pp.80-86
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• 1996

Naphthalene hydrogenation reaction was performed as a model reaction for coal liquefaction. Product distributions of tetralin and decalin are sensitive to reaction temperature and hydrogen pressure. At 380$^{\circ}C$, hydrogenation reaction using sulfided pellet catalysts gives poor reproducibility and several experimental methods are tried to examine its cause. It was inferred that H$_2$S had, most possibly, a great effect on this phenomena and the effect of H$_2$S was systematically investigated at 250$^{\circ}C$. It is possible that the intermediate hydroaromatic compound (tetralin) is maximized by changing the partial pressure of H$_2$S. It was identified that the partial pressure of H$_2$S could be another important factor in addition to the reaction time and temperature in coal liquefaction using sulfided catalysts.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.4
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• pp.322-326
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• 1992

Epiphora is overflow of tears due to obstruction of lacrimal duct. Dacryocystorhinostomy is the most common procedure to eliminate the epiphora secondary to complete or partial obstruction of the nasolacrimal duct. The procedure is to artificially create passage between lacrimal sac and nasal cavity. Especially, epiphora would be accompany often by nasolacrimal duct obstruction when trauma of oromaxillofacial area lead to nasal fracture, medial wall fracture of orbit. Therefore in this case there are many case to perform dacryocystorhinostomy because probing and tubing is difficult to resolve the epiphora. We performed 4 cases of dacryocystorhinostomy for adult nasolacrimal duct obstruction from May 1991 to October 1991. The results were very satisfactory in all the case. Epipora disappeared in all case.

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1076-1081
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• 1998

The purpose of this research was to isolate an active component on immunoytes from 70% MeOH extract of Codonopsis lanceolatae Radix(CLE). CLE was fractionated successively with hexane, methylene chloride, n-butyl alcohol and water, and then the water fraction was separated with molecularporous membrane tubing(m.w. 3,500). Each fraction(50mg/kg) was administered p.o. once a day for 7 days in BALB/c mice respectively. None of these fractions affected the apoptosis and mitochondrial transmembrane potential in thymocyte. Hexane and methylene chloride fractions decreased CD4$^{[-10]}$ CD8$^{+}$ single-positive cells, and the water fraction enhanced CD4$^{+}$ CD8$^{[-10]}$ single-positive cells in thymocyte. The proliferation of thymocytes was decreased by the fraction hexane, but was enhanced by the water fraction. Hexane, methylene chloride and butyl alcohol fractions suppressed the production of nitric oxide, which was not affected by the water fraction. Hexane and butyl alcohol fraction suppressed the phagocytic activity, but water fraction enhanced it. The components(m.w. 3,500 above) separated from the water fraction enhanced the proliferation of thymocyte, the population of CD4$^{+}$ CDB$^{[-10]}$ single-positive cells, and phagocytic activity in macrophage. These results suggest that the stimulative components of proliferation, TH population and phagorytc activity is in the water fraction, and the molecular weight is 3,500 above. (Korean J Nutrition 31(6) : 1076~1081, 1998) 1998)

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.79-83
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• 1999

A potentiometric biosensor employing a CO3-2 ion-selective electrode(ISE) and malic enzyme immobilization in al flow injection analysis (FIA) system was constructed. Analytical parameters were optimized for L-malate determination . The CO3-2 -ISE-FIA system was composed of a pump, an injector, a malic enzyme (EC1.1.1.40) reactor, a CO3-2 ion-selective electrode, a pH/mV meter and a recorder. Cofactor NADP was also injected with substrate for theenzyme reaction into the system. Optimized analytical parameters for L-malate determination in the CO3-2 ISE-FIA system were as follows ; flow rate, 14.5ml/hr ; sample injection volume, 100ul; enzyme loading in the reactor, 20 units ; length of the enzyme reactor , 7 cm ; tubing length form the enzyme reactor to the detector as a geometric factor in FIA, 15 cm . The response time for measuring the entire L-malate concentration range (10-2 ~10-5 mol/L ; 4 injections )was <15minutes . In this CO3-2 -ISE-FIA system, the potential differences due to th eformation of CO3-2 by the reaction of malic enzyme on L-malate were correlated to L-malate concentration in the range of 10-2 ~10-5mol/L ; the detection limit was 10-5 mol/L. This potentionmetric CO3-2 ISE--FIA system was found to be useful for L-malate measurement.

• Preventive Nutrition and Food Science
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• v.2 no.1
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• pp.35-41
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• 1997

The pancreas is an important organ in the maintenance of zinc homeostasis. Endogenous zinc is con-tinuously secreted via pancreatic exocrine fluid or to a lesser extent in bile. Much of the endogenous secretion must be reabsorbed to sustain zinc homeostasis. The objective of this study was to estimate the relative size of the pancreatic/biliary zinc pool in comparision to the dietary zinc intake, and to study the effect of the phytate and calcium on the zinc homeostasis using a rat model. At the termination of the experiment, pan-creatic/biliary fluid was collected from the rats. Both radioactivity and total zinc were measured and the relative size of the pancreatic/biliary zinc pool was estimated. To determine the effect of phytate and calcium on zinc homeostsis, dietary zinc intake, the amount of zinc in pancreatic.biliary fluid and fecal zinc excretion were measured. The flow rate of pancreatic/biliary fluid, as corrected for tubing constriction, gives the corrected zinc concentration in the pancreatic/biliary fluid was 2.2 times higher than dietary zinc intake. To maintain zinc homeostasis, zinc absorption/reabsorption was very efficient in the current model; 76%, 88% of absorption/reabsorption for low calcium group and high calcium group 81% for phytate group and non-phytate group, respectively.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1399-1403
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• 1992

The evaluation of the effectivess of ongoing cardiopulmonary resucitation efforts is dependent on the commonly used methods, such as the presence of femoral or carotid artery pulsations, arterial blood gas determinations, peripheral arterial pressure and intracardiac pressure monitoring. But recent studies suggest that end-tidal carbon dioxide tension serves as a non-invasive measurement of pulmonary blood flow and therefore cardiac output under constant ventilation. A prospective clinical study was done to determine whether end-tidal carbon dioxide monitoring in open heart surgery under cardiopulmonary bypass could be used as a prognostic indicator of bypass weaning. We monitored end-tidal PCO2 values continuously during cardiopulmonary bypass in 30 patients. "Ohmeda 5210 CO-2 monitor" under infrared absorption method were incorperated into the ventilator circuit by means of a side point adaptor between endotracheal tube and ventilator tubing. 18 patients[Group I ] were res-ucitated from partial bypass followed by aorta cross clamp off and 12 patients[Group II ] from aorta cross clamp off followed by partial bypass. But there was no difference between two groups[p>0.05]. The value of end-tidal carbon dioxide tension during ventricular fibrillation or nearly arrest state was 6.6$\pm$2.9 mmHg, and at the time of spontaneous beating was 19.3$\pm$5.6 mmHg[Mean$\pm$Standard deviation], In conclusion end-tidal carbon dioxide tension monitoring provides clinically useful, continous, noninvasive and supplementary prognostic indicator during cardiopulmonary bypass weaning procedures.rocedures.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.4
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• pp.526-533
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• 2011

This research is about the pulsatile pump system utilized in the perfusion bioreactor for the in vitro human tissue culture. A pulsatile pump system which can be applied to the culture of the vascular tissues including blood vessel is developed by using the idea of human heart's blood pumping into organs as followings: culture chamber, a pressurizing device which generates laminar pulsatile flow by controlling the x-sectional area of the culture media delivering tubing, a compliance chamber which supplies the pressuring device with a constant pressure, and a peristaltic pump which circulates the culture media in a circuit ranging from the culture chamber to the compliance chamber. The developed pulsatile pump system shows that a physiology of the human heart's blood pumping including pulsatile pressure waveform of systolic-diastolic pressure is well represented. Not only time domain but also frequency domain characteristics of pulsatile pump system which are necessary for the vascular tissue culture such as pulsatile pressure waveform's shape, the frequency, and the magnitude can be easily generated and manipulated by using the proposed system.

• Journal of Pharmaceutical Investigation
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• v.18 no.1
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• pp.15-21
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• 1988

An inclusion complex of phenytoin (PT) with ${\beta}-cyclodextrin\;({\beta}-CyD)$ in molar ratio of 1 : 1 was prepared, and the interaction between host and guest molecules was confirmed by infrared spectrometry, differential scanning calorimetry and X-ray diffractometry. Suppositories were prepared by the fusion method. PT and $PT-{\beta}-CyD$ complex were added to PEG 1540 and Witepsol H-15 under the vigorous stirring at $40^{\circ}C$. Content uniformity was tested for different formulations of the PT suppositories. The release rates were dependent on the K.P. V dissolution apparatus and the dialyzing tubing method. Then, the release rates were increased in the following order: $PT-{\beta}-CyD$ complex in PEG 1540>PT in PEG 1540>$PT-{\beta}-CyD$ complex in Witepsol H-15>PT in Witepsol H-15. The area under the curve and maximum blood concentration after rectal administration were increased in the following order: $PT-{\beta}-CyD$ complex in PEG 1540>PT in PEG 1540>$PT-{\beta}-CyD$ complex in Witepsol H-15>PT in Witepsol-15.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.4
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• pp.19-25
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• 2011

Steam Generator(SG) tube is an important component of Nuclear Power Plant(NPP), which is the pressure boundary between the primary and secondary systems. The integrity of SG tube has been confirmed by the eddy current test every outage. The eddy current technique adopting bobbin probe is currently the primary technique for the steam generator tubing integrity assesment. The bobbin probe is one of the essential components which consist of the whole ECT examination system and provides us a decisive data for the evaluation of tube integrity. Until now, all of the ECT bobbin probes in Korea which is necessary to carry out inspection are imported from overseas. However, KHNP has recently developed the bobbin probe design technology and transferred it to domestic manufacturers to fabricate the probes. This study has been conducted to establish technical requirements applicable to the steam generator tube inspection using the bobbin probes fabricated by the domestic manufactures. The results have been compared with the results obtained by using foreign probe to identify the availability to the steam generator tube inspection. As a result, it is confirmed that the domestic bobbin probe is generally applicable to SG tube inspection in the NPPs.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.64-70
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• 2019

In recent years, attention has been paid to the integrity of steam generator (SG) tubes due to severe accident and beyond design basis accident conditions. In these transient conditions, steam generator tubes may be damaged by high temperature and pressure, which might result in a risk of fission products being released to the environment due to the failure. Alloy 690 which has increased the Cr content has been replaced for the SG tube due to its high corrosion resistance against stress corrosion cracking (SCC). However, there is lack of research on the high temperature creep rupture and life prediction model of Alloy 690. In this study, creep test was performed to estimate the high temperature creep rupture life of Alloy 690 using tube specimens. Based on manufacturer's creep data and creep test results performed in this study, creep life prediction was carried out using the Larson-Miller (LM) Parameter, Orr-Sherby-Dorn (OSD) parameter, Manson-Haford (MH) parameter, and Wilshire's approach. And a hyperbolic sine (sinh) function to determine master curves in LM, OSD and MH parameter methods was used for improving the creep life estimation of Alloy 690 material.