• Clean Technology
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• v.20 no.2
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• pp.189-201
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• 2014

Partial oxidation, $CO_2$ reforming and the oxidative $CO_2$ reforming of $CH_4$ to produce synthesis gas over supported Ni hydrotalcite-type ($Ni_{0.5}Ca_{2.5}Al$ catalyst) catalysts were carried out and the effects of metal supports (i.e.; Mg and Ca) on the formation of a stable double-layer structure on the catalysts were evaluated. The $CH_4$ reforming stability was determined to be affected by the differences in the interaction strength between the active Ni ions and support metal ions. Only a Ni-Mg-Al composition produced a highly stable hydrotalcite-type double-layered structure; while the Ni-Ca-Al-type composition did not. Such structure provides excellent stability for the catalyst (-80% efficiency) as confirmed by the long-term $CO_2$ reforming test (-100 h), while the Ni-Ca-Al catalyst exhibited deactivation phases starting at the beginning of the reaction. The interaction strength between the active metal (Ni) and the supporting components (Mg and Al) was determined by temperature-programed reduction (TPR) analyses. The affinity was also confirmed by the TPR temperature because the Ni-Mg-Al catalyst required a higher temperature to reduce the Ni relative to the Ni-Ca-Al catalyst. The highest initial activity for synthesis gas production was observed for the $Ni_{0.5}Ca_{2.5}Al$ catalyst; however, this activity decreased quickly due to coke formation. The $Ni_{0.5}Ca_{2.5}Al$ catalyst exhibited a high reactivity and was more stable than the other catalysts because it had a higher resistance to coke formation.

• Tuberculosis and Respiratory Diseases
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• v.40 no.6
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• pp.638-645
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• 1993

Objectives: The functional effects of pulmonary resection are dependent on the preexisting function of resected and remaining tissue as well as on the compensatory potential of the remaining tissue. Nowadays, large pulmonary resections are usually applied to lung cancer patients often already compromised by chronic lung disease. It is important to evaluate the pulmonary reserve after lung resection preoperatively in the decision of operability and extent of resection. The aim of this study was to evaluate the changes of pulmonary function after pulmonary resection. Methods: 8 lobectomized and 8 pneumonectomized patients were evaluated. The pulmonary function test was performed preoperatively and in immediate postoperative period and thereafter to 5 years at 3 months interval. Results: 1) The pulmonary function 1 week after operation was significantly low compared with predicted values in, lobectomy and pneumonectomy groups(p<0.05), and improved closely to their predicted values 3 months after operation. 2) The FVC was maintained above predicted value at 6-24 months and similar to predicted value thereafter in lobectomy group. In pneumonectomy group, the FVC maintained similar to predicted value at 6-36 months and improved above its predicted value thereafter. 3) The FEV1 was maintained similar to their predicted values from 6 months to 5 years after operation in both groups. 4) The FEV1/FVC did not change in the course of time in both groups. 5) The FEF25-75% was maintained similar to predicted value at 6-60 months after operation in lobectomy group, but it decreased under predicted value after 1 year in pneumonectomy group. 6) The MVV was maintained similar to predicted value at 6-24 months and decrease thereafter in lobectomy group. In pneumonectomy group, the MVV was maintained at 6-60 months after operation. 7) The differeces in the pulmonary function(FVC, FEV1, FEF25-75%, MVV) between two groups were seen only at 6 months after operation(p<0.05). Conclusion: The pulmonary function was markedly decreased immediately after operation, improved similar to predicted value at 1-3 months, highest at 6 months, and maintained similar to the predicted value to 5 years after pulmonary resection. The difference in the pulmonary function between two groups was the most at 6 months after operation.

• Tuberculosis and Respiratory Diseases
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• v.61 no.1
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• pp.20-25
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• 2006

Background: Although fever is one of the most common and challenging problem in intensive care medicine(ICU), it is difficult to distinguish between infectious and non-infectious causes. Procalcitonin(PCT) has recently been reported to be an indicator of various infectious diseases. This study examined whether or not measuring the serum PCT level in patients with fever in the ICU can help distinguish fevers with infectious causes from those with non-infectious causes. Methods: ICU patients with fever at $38^{\circ}C$ or over from March to August 2005 were prospectively enrolled. The cause of the fever was identified by the culture results and clinical course. The leukocytes, CRP, PCT, IL-6, and $TNF-{\alpha}$ in the fever patients with infectious and non-infectious causes were compared, and the PCT level in the patients with fever in the ICU were compared with those without fever. Results: 1) 42 patients were enrolled and 46 cases of fever were analyzed. 26 cases were considered to be infectious, while 13 cases were considered to be non-infectious. 7 cases were found to have no clear causes. 2) There were no significant differences in the degree of fever, leukocytes count, CRP, IL-6, and $TNF-{\alpha}$ levels in the patiemts with infectious and non-infectious causes. 3) The serum PCT level was higher in those with infectious causes than in those with non-infectious causes ($15.1{\pm}32.57ng/mL$ vs $2.68{\pm}3.63ng/mL$) but there was no statistical significance (p=0.06). 4) The serum PCT level of the ICU patients with fever was significantly higher than in those without fever ($10.94{\pm}27.15ng/mL$ vs $0.45{\pm}0.49ng/mL$) (p=0.02). Conclusion: The serum PCT cannot be used to distinguish the fever in ICU patients with infectious causes from that with non-infectious causes.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.1
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• pp.48-54
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• 2010

Purpose: The objective of this study was to evaluate and compare the accuracy of impression body taking by the closed and the open tray impression technique with 3 types of impression tray. Individual tray, metal stock tray and polycarbonate tray were used. Materials and methods: Nine closed tray impressions were taken by individual tray, metal stock tray and polycarbonate stock tray, respectively with polyether impression material. 9 open tray impressions were also acquired by same manner. Precision analysis on the master models was performed by attaching the reference frameworks with alternate single screws and measuring the vertical fit discrepancy of respective analogues in working cast with a stereo microscope. Data were analyzed by 1 way ANOVA and independent t-test. Results: The average fit accuracy of impression bodies was calculated. With the closed tray impression technique, there were significant statistical differences in vertical fit discrepancy according to the types of tray. The individual tray group showed the lowest value and the polycarbonate stock tray group represented the highest. With the open tray impression technique, there was no significant difference in vertical fit discrepancy. Significant statistical difference in vertical fit discrepancy was found between the open and the closed impression technique with the polycarbonate stock tray. Conclusion: From the results above, more precise impressions could be acquired by the rigid individual tray compared with the polycarbonate stock tray. It was hard to get consistent accuracy impressions by the closed tray impression technique with polycarbonate stock trays.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.333-340
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• 2011

Purpose: The aim of this study was to study the effect of hydroxyapatite (HA) coating crystallinity on the proliferation and differentiation of human osteosarcoma cells. Materials and methods: Surface roughness of the titanium disks increased by anodizing treatment and then HA was coated using ion beam-assisted deposition (IBAD). HA coating was crystallized by heat-treated at different temperature ($100^{\circ}C$, $300^{\circ}C$, $500^{\circ}C$, $800^{\circ}C$). According to the temperature, disks were divided into four groups (HA100, HA300, HA500, HA800). With the temperature, crystallinity of the HA coating was different. Anodized disks were used as control group. The physical properties of the disk surface were evaluated by surface roughness tests, XRD tests and SEM. The effect of the crystallinity of HA coating on HOS cells was studied in proliferation and differentiation. HOS cells were cultured on the disks and evaluated after 1, 3, 5, and 7 days. Growth and differentiation kinetics were subsequently investigated by evaluating cell proliferation and alkaline phosphatase activity. Results: Regardless of the heat-treated temperature, there is no difference on the surface roughness. Crystallinity of the HA was appeared in the groups of HA500, HA800. HOS cells proliferation, ALP activity were higher in HA500 and HA800 group than HA100 and HA300. Conclusion: Within the results of this limited study, heat treatment at $500^{\circ}C$ of HA coating produced by IBAD has shown greater effect on proliferation and differentiation of HOS cells. It is considered that further in vivo study will be necessary.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.347-353
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• 1997

This study was to test whether in vitro/in vivo survival of vitrified mouse blastocysts was influenced by culture conditions and ET method. Mouse blastocysts were obtained from in vitro fertilization and cultured for 4 days in M16 medium, and they were vitrified in EFS40 which contained 40% ethlyene glycol, 18% Ficoll and 0.5 mol sucrose in PBS. In experiment I, in vitro and in vivo survival rate of these embryos were evaluated in different culture condition after thawing. When thawed embryos were cultured in M16 medium as a control, m-CR1 medium contained 20 amino acids (2% BME amino acis and 1% MEM non-essential amino acids solution) and 4 mg/ml BSA and cumulus monolayer cell co-cultured condition in mCR1 medium (10% FBS), their in vitro survival at 24 hr after thawing was not affected by culture condition (75.6, 83.1, 82.4%). However, in vivo survival rates of implantation in m-CR1 medium (80.4%) were significantly higher than those of M16 medium (51.2%), co-culture (57.1%) condition, although there was no difference in live fetuses rates on day 15 gestation (39.0, 49.0, 38.1%). In experiment II, the in vivo development potential of embryos by ET methods was examined. When blastocysts were transferred to the day 2, 3 pseudopregnant recipient without culture soon after thawing, no pregnant recipient was obtained on the day 2 pseudopregnancy, and 50% of pregnancy rates and 15.4% of live fetus rates were obtained on the day 3 pseudopregnant recipients. These results were significantly lower than those of transferred group (day 3 pseudopregnant recipients) after culture for 16 hr post thawing (73.5, 57.1%) (p<0.05). In experiment III, to elevate usability of delayed embryos in vitro/in vivo survival of vitrified embryos (day 4 early, day 5 early and expanding blastocyst) were examined. in vivo survival rates (live fetus, total implantation) were higher in day 4 early blastocysts (33.3, 66.7%) than in day 5 expanding blastocysts (29.0, 38.7%), although the highest in vitro survival rates were obtained in the day 5 expanding brastocysts (78.3%). Therefore, these results suggest that the in vitro/in vivo survival rates of vitrified embryos could be improve by the culture condition and ET method and that the in vivo development rates of delayed embryos were decreased with longer culture duration in vitro. It means that more effective cryopreservation was obtained in day 4 early blastocysts than in day 5 expanding blastocysts.

• The Journal of the Petrological Society of Korea
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• v.20 no.1
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• pp.39-59
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• 2011

To get the geologic information data such as rock resources, industrial ground, development planning and so on, distribution ratios of constituent rocks with geologic age and rock type were obtained in Gyeongnam, Ulsan and Busan areas by ArcGIS 9.3 program, digital geologic and geomorphic maps of 1 : 250,000 scale. Geologic ages and rock types in the Gyeongnam area can be divided into 6 and 40, respectively. Their distribution ratios of the geologic ages are decreasing in the order of Cretaceous, Precambrian, Quaternary, Jurassic, Triassic and Tertiary. They show the wide ranges of 1.35-57.36%, and the former makes the most dominant ratio. Major rock types are 24 ones, all of which occupy the ratio of 94.58% and relatively narrow ranges of 1.15-13.64% in the area. Among them, andesite and andesitic tuff shows the more or less dominant ratio, and separately develops in the northeast, mid east and south parts of the area. In the Ulsan area, geologic ages and rock types can be divided into 3 and II, respectively. Their distribution ratios of the geologic ages are decreasing in the order of Cretaceous, Quaternary and Triassic. They show the very wide range of 6.90-79.21%, and the former makes the most prevailing ratio. Major rock types are 9 ones, which totally occupy the ratio of 98.63% and more or less wide ranges of 1.50-39.01% in the area. Among them, Jindong formation shows the most dominant ratio, and widely develops in the inner and eastern part of the area. In the Busan area, geologic ages and rock types can be divided into 3 and 10, respectively. Their distribution ratios of the geologic ages are decreasing in the order of Cretaceous, Quaternary and Tertiary. They show the wide ranges of 6.73-47.02%, and the two former makes the most dominant ratio of 88.03%. Major rock types are 6 ones, all of which occupy the ratio of 93.02% and relatively wide ranges of 4.07-47.02% in the area. Among them, alluvium forms the most dominant ratio, which mostly develops in the lower Nagdong River, West Nagdong River and Suyeong River.

• Geophysics and Geophysical Exploration
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• v.5 no.4
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• pp.223-235
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• 2002

Since weak Bones or geological lineaments are likely to be eroded, there may develop weak Bones beneath rivers, and a careful evaluation of ground condition is important to construct structures passing through a river. DC resistivity method, however, has seldomly applied to the investigation of water-covered area, possibly because of difficulties in data aquisition and interpretation. The data aquisition having high quality may be the most important factor, and is more difficult than that in land survey, due to the water layer overlying the underground structure to be imaged. Through the numerical modeling and the analysis of a case history, we studied the method of resistivity survey at the water-covered area, starting from the characteristics of measured data, via data acquisition method, to the interpretation method. We unfolded our discussion according to the installed locations of electrodes, ie., floating them on the water surface, and installing them at the water bottom, because the methods of data acquisition and interpretation vary depending on the electrode location. Through this study, we could confirm that the DC resistivity method can provide fairly reasonable subsurface images. It was also shown that installing electrodes at the water bottom can give the subsurface image with much higher resolution than floating them on the water surface. Since the data acquired at the water-covered area have much lower sensitivity to the underground structure than those at the land, and can be contaminated by the higher noise, such as streaming potential, it would be very important to select the acquisition method and electrode array being able to provide the higher signal-to-noise ratio (S/N ratio) data as well as the high resolving power. Some of the modified electrode arrays can provide the data having reasonably high S/N ratio and need not to install remote electrode(s), and thus, they may be suitable to the resistivity survey at the water-covered area.

• Journal of the Korean Vacuum Society
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• v.19 no.3
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• pp.211-216
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• 2010

The luminescence properties of $In_{0.5}Ga_{0.5}As/In_{0.5}Al_{0.5}As$ multiple quantum wells (MQWs) grown on $In_{0.5}Al_{0.5}As$ buffer layers have been studied by using photoluminescence (PL) and time-resolved PL measurements. A$1-{\mu}m$ thick $In_{0.5}Al_{0.5}As$ buffer layers were deposited on a 500 nm thick GaAs layer, followed by the deposition of the InGaAs/InAlAs MQWs. In order to investigate the effects of InAlAs buffer layer on the optical properties of the MQWs, four different temperature sequences are used for the growth of InAlAs buffer layer. The growth temperature for InAlAs buffer layer was varied from 320^{\circ}C to $580^{\circ}C$. The MQWs consist of three $In_{0.5}Ga_{0.5}$As wells with different well thicknesses (2.5 nm, 4.0 nm, and 6.0 nm thick) and 10 nm thick $In_{0.5}Al_{0.5}$As barriers. The PL spectra from the MQWs with InAlAs layer grown at lower temperature range ($320-580^{\circ}C$) showed strong peaks from 4 nm QW and 6 nm QW. However, for the MQWs with InAlAs buffer grown at higher temperature range ($320-480^{\circ}C$), the PL spectra only showed a strong peak from 6 nm QW. The strongest PL intensity was obtained from the MQWs with InAlAs layer grown at the fixed temperature of $480^{\circ}C$, while the MQWs with buffer layer grown at higher temperature from $530^{\circ}C$ to $580^{\circ}C$ showed the weakest PL intensity. From the emission wavelength dependence of PL decay times, the fast and slow decay times may be related to the recombination of carriers in the 4 nm QW and 6 nm QW, respectively. These results indicated that the growth temperatures of InAlAs layer affect the structural and optical properties of the MQWs.

• Food Science and Preservation
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• v.24 no.6
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• pp.802-812
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• 2017

This study was conducted to investigate the quality properties depending on the cultivation methods (general, organic, pesticide-free) of yuza and its various parts (peel, pulp, seed). The contents of hesperidin were the highest in yuza feel grown by pesticide-free method (13.23 mg/g). The contents of naringin presented a higher content in the peel, especially which of the general (4.62 mg/g) showed the highest value. Vitamin C analysis showed the highest content in the peel, significantly varied according to the cultivation method and various parts (p<0.05). Vitamin C value was significantly highest in organic peel, which was 770.02 mg/100 g, whereas among the peel, the pulp and the seed were it the lowest in the seed. The content of total polyphenols were the highest in general peel (0.85 mg/g). Flavonoid content of pesticide-free seed was significantly higher than those of the other yuja samples which was 0.89 mg/g (p<0.05). The DPPH radical scavenging activity was relatively more active in the peel among the above-mentioned three parts, especially the pesticide-free peel was most active, which was 73.94%. The ABTS radical scavenging activity of organic peel was significantly active among the samples, which was 84.47% (p<0.05). Based on these results, it can be said that yuja has variety of useful components in the pulp and the seed as well as the peel: and thus it's hight recommended to develop more varied yuja products.