• Journal of Advanced Marine Engineering and Technology
• /
• v.39 no.8
• /
• pp.833-837
• /
• 2015

Li-air batteries have a promising future for because of their high energy density, which could theoretically be equal to that of gasoline. However, substantial Li-air cell performance limitations exist, which are related to the air cathode. The cell discharge products are deposited on the surfaces of the porous carbon materials in the air electrode, which blocks oxygen from diffusing to the reaction sites. Hence, the real capacity of a Li-air battery is determined by the carbon air electrode, especially by the pore volume available for the deposition of the discharged products. In this study, a simple and fast method is reported for the large-scale synthesis of carbon nanoballs (CNBs) consisting of a highly mesoporous structure for Li-air battery cathodes. The CNBs were synthesized by the solution plasma process from benzene solution, without the need for a graphite electrode for carbon growth. The CNBs so formed were then annealed to improve their electrical conductivity. Structural characterization revealed that the CNBs exhibited both an pore structure and high conductivity.

• Journal of Applied Biological Chemistry
• /
• v.50 no.4
• /
• pp.187-195
• /
• 2007

The cord blood serves as a vehicle for the transportation of oxygen and nutrients to the fetus. In the past, the human cord blood has generally been discarded after birth. However, numerous studies have described the regenerative ability of the cord blood cells in various incurable diseases. The umbilical cord blood (UCB)-derived stem cells are obtained through non-invasive methods that are not harmful to both the mother and the fetus. Furthermore, the cord blood stem cells are more immature than the adult stem cells and expand readily in vitro. The mesenchymal stem cells (MSCs) have the capacity to differentiate in vitro into various mesodermal (bone, cartilage, tendon, muscle, and adipose), endodermal (hepatocyte), and ectodermal (neurons) tissues. This review describes the immunological properties of the human UCB-MSCs to assess their potential usefulness in the allogeneic transplantation for the regenerative medicine.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.4
• /
• pp.301-304
• /
• 2002

The variation of alternative and cytochrome respiration during ripening in rice leaves (Oryza sativa L. cv. Takanari) was examined. The capacity of both respiration pathway was measured by inhibitor titration method using gas-phase oxygen electrodes. The alternative respiration rate decreased from 31.3% of the total respiration rate at around heading to 11.7% at 34 days after heading in the first fully expanded leaf from the top, and further to 6.4 % at 34 days after heading in the fourth leaf from the top. In contrast, the proportion of cytochrome respiration to total respiration increased with leaf senescence. The possible cause of alternative respiration as either an increase in inefficient respiration or a decrease in growth efficiency during ripening was discussed.

• Korean Journal of Pharmacognosy
• /
• v.46 no.4
• /
• pp.303-308
• /
• 2015

Ten phenolic compounds were isolated from the twigs of Stewartia pseudocamellia. The isolated compounds were identified as 5,7,3',5'-tetrahydroxyflavanone (1), 3,5,7,3',5'-pentahydroxyflavanone (2), quercetin (3), (+)-aromadendrin (4), (+)-ampelopsin (5), myricetin (6), (+)-catechin (7), (-)-epicatechin (8), kaempferol (9), and fraxin (10) by spectroscopic analysis. Compounds 1, 2, 4, 6, 8, and 9 were isolated from this plant for the first time. The antioxidant activities of compounds 1-10 were evaluated by the DPPH and/or ORAC (oxygen radical absorbance capacity) assay. Compounds 3, 5-9 showed significant antioxidative effects on DPPH assay. Among the active compounds, 6 exhibited higher activity compared to trolox on ORAC assay.

• Korean Journal of Pharmacognosy
• /
• v.46 no.4
• /
• pp.289-294
• /
• 2015

Seven flavonoids were isolated from the flower of Clerodendrum trichotomum. Their structures were identified as apigenin (1), genistein (2), chrysoeriol (3), genistein 7-O-glucoside (4), kaempferol 3-O-glucoside (5), isorhamnetin 3-O-glucoside (6) and apigenin 7-O-glucoside (7) on the basis of spectral data. These compounds were isolated from C. trichotomum for the first time. The antioxidant activity of compounds 1-7 were evaluated by the ORAC (oxygen radical absorbance capacity) assay, and the ORAC values were expressed as relative trolox equivalent. All isolated compounds exhibited antioxidant activity.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2003.04a
• /
• pp.455-458
• /
• 2003

We investigated the leaching of elements from anthracite ashes by interactions with seawater. The results show that consumption rates of dissolved oxygen are 7.5 times greater in the seawater system than in the fresh water system and indicate that the differences in DO consumption rate may plat a role in regulating the element leaching from the coal ashes. It is revealed that seawater's pH buffering capacity is the most important factor that makes the leaching of elements and their chemical behaviors in the seawater system different from those in the fresh water environments. In overall, element leaching from the weathered ash is smaller than that from the fresh ash. However, the leaching of Si, Fe, Al, Mn, phosphate, and some other elements were independent of weathering. They were dependant only on the pH of the solutions.

• 유체기계공업학회:학술대회논문집
• /
• 2004.12a
• /
• pp.347-351
• /
• 2004

The cryogenic test facility is developed for test of deep groove ball bearings, floating ring seals, materials (steel & copper) for High Pressure Turbopump of liquid rocket engine (LRE). The cryogenic bearing test is performed to evaluate the flow rate of cooling water and the load-carrying capacity of bearings. The cryogenic seal test is performed to evaluate the determination of magnitude of leakages through the seal, a time variation of this magnitude. The test of the materials Pair is performed to evaluate its fitness for operation in the liquid oxygen medium.

• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.3
• /
• pp.379-383
• /
• 2007

The effects of phenolic acids on the physical properties of wheat flour extrudate were investigated. Ferulic acid, fumaric acid, and p-coumaric acid were mixed with hard wheat flour, respectively, and extruded under a twin screw extruder. We found that by adding the phenolic acids, longitudinal expansion at the die increased, textural hardness decreased, and the water absorption capacity of the extrudate decreased. The results showed that the addition of phenolic acids produced a softer textured, more longitudinally puffed and hydrophobic extrudate compared to the control extrudate. Moreover, the addition of phenolic acids did not significantly affect the color of the extrudate: oxidative browning of the phenolic acids was not observed, due to inactivation of the browning enzymes under the hot temperature and reduced oxygen conditions of the extrusion process.

• Tuberculosis and Respiratory Diseases
• /
• v.83 no.4
• /
• pp.257-267
• /
• 2020

Patients with chronic obstructive pulmonary disease receive a range of treatments including but not limited to inhaled bronchodilators, inhaled and systemic corticosteroids, supplemental oxygen, and pulmonary rehabilitation. Pulmonary rehabilitation is a multidisciplinary intervention that seeks to combine patient education, exercise, and lifestyle changes into a comprehensive program. Programs 6 to 8 weeks in length have been shown to improve health, reduce dyspnea, increase exercise capacity, improve psychological well-being, and reduce healthcare utilization and hospitalization. Although the use of pulmonary rehabilitation is widely supported by the literature, controversy still exists regarding what should be included in the programs. The goal of this review was to summarize the evidence for pulmonary rehabilitation and identify the areas that hold promise in improving its utilization and effectiveness.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.1
• /
• pp.387-392
• /
• 2006

There have been several problems in treating shipboard sewage due to special environmental conditions of ship, such as limited space, rolling and pitching, change of temperature and so on. It was suggested that Sequence Batch Reactor (SBR) might be suitable process for overcome these problems in terms of small size, high capacity of treating wastewater and full automation. In this study a SBR process was employed for biological treatment of organic wastes in the shipboard sewage. This process was able to remove nitrogen and phosphorus as well as organic matter efficiently. More than 95% of chemical oxygen demand(COD) were removed. In addition, about 97% of total nitrogen (T-N) was reduced. The total phosphorus(T-P) reduction averaged 93%. A disturbance operation caused by the treatment of Methylene Blue Active Substances(MBAS) was not observed.