• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.3
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• pp.143-148
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• 2021

Alkaline oxygen evolution reaction (OER) electrocatalysts have been widely studied for improving the efficiency and green hydrogen production through electrochemical water splitting. Transition metal-based electrocatalysts have emerged as promising materials that can significantly reduce the hydrogen production costs. Among the available electrocatalysts, transition metal-based layered double hydroxides (LDHs) have demonstrated outstanding OER performance owing to the abundant active sites and favorable adsorption-desorption energies for OER intermediates. Currently, cobalt doped nickel LDHs (NiCo LDHs) are regarded as the benchmark electrocatalyst for alkaline OER, primarily owing to the physicochemical synergetic effects between Ni and Co. We report effects of heat-treatment of the as-grown NiCo LDH on electrocatalytic activities in a temperature range from 250 to 400℃. Electrocatalytic OER properties were analysed by linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). The heat-treatment temperature was found to play a crucial role in catalytic activity. The optimum heat-treatment temperature was discussed with respect to their OER performance.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.54-59
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• 2021

DIWS system was introduced to remove hydrogen sulfide from the biogas of wastewater treatment plant. In the case of using water into the DIWS system more than 5,000mg/L of hydrogen sulfide, 25% of H2S removal efficiency was shown and required such further treatment process as incineration which was obtained more than 98%. When the inflow of hydrogen sulfide was 5,000mg/L, CH4 and CO2 were effectively discharged and the reduction was 8.7% and 28.6%, respectively. When such neutralization chemicals as Na2CO3 and NaOH were introduced into the DIWS system, H2S was removed more than 97.2% keeping pH in the range of 11.2 to 11.5.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.4
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• pp.261-272
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• 2021

Doxorubicin (Dox) is widely used to the treatment of cancer, however, it could cause damage to gastric mucosa. To investigate the protective effects and related mechanisms of coenzyme Q10 (CoQ10) and vitamin C (VC) on Dox-induced gastric mucosal injury, we presented the survey of the 4 groups of the rats with different conditions. The results showed Dox treatment significantly induced GES-1 apoptosis, but preconditioning in GES-1 cells with VC or CoQ10 significantly inhibited the Dox-induced decrease and other harm effects, including the expression and of IκKβ, IκBα, NF-κB/p65 and tumor necrosis factor (TNF-α) in GES-1 cells. Moreover, high-throughput sequencing results showed Dox treatment increased the number of harmful gut microbes, and CoQ10 and VC treatment inhibited this effect. CoQ10 and VC treatment inhibits Dox-induced gastric mucosal injury by inhibiting the activation of the IkKB/IκBα/NF-κB/p65/TNF-α pathway, promoting anti-inflammatory effects of gastric tissue and regulating the composition of the intestinal flora.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.3
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• pp.145-152
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• 2013

This study aimed to investigate the growth and physiological characters of Liriodendron tulipifera seedlings in responses to two different levels of elevated air temperature and $CO_2$ concentration. The seedlings were grown in environment-controlled growth chambers with two combinations of air temperature and $CO_2$ conditions: (1) $22^{\circ}C$ + ambient $CO_2$ $380{\mu}mol\;mol^{-1}$ and (2) $27^{\circ}C$ + $770{\mu}mol\;mol^{-1}$. Physiological characters such as growth, photosynthesis, and water use efficiency, were monitored for 85 days. The seedlings under the elevated treatment showed a greater amount of growth in tree height, compared with those under the control. Regarding the characteristics of assimilatory organs, the elevated treatment resulted in a greater amount of total leaf area, leaf unfolding, and dry weight per leaf area. No significant differences were found in photosynthesis capacity between the two treatments. The increase in water use efficiency with increased intercellular $CO_2$ partial pressure appeared overall lower in the seedling under the elevated treatment, compared with those under the control. The total leaf area of the seedlings under the elevated treatment was larger than that under the control, indicating a higher amount of photosynthesis. In addition, an increase of root growth was noted under the elevated treatment. A resistance mechanism of water stress may be attributed to a higher amount of organ growth as well as the tree height under the elevated treatment than the control.

• Reproductive and Developmental Biology
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• v.36 no.3
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• pp.141-145
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• 2012

The present study was conducted to develop a simple method for porcine oocyte maturation without $CO_2$ regulation. In experiment 1, we evaluated that the effect of $CO_2$ non-supplement on porcine oocyte maturation. Cumulusoocyte complexes (COCs) were collected from 2~6 mm follicles and divided into three groups (Control, tube-$CO_2$, and tube-non-$CO_2$). For control, COCs were cultured in 4-well multidish in a $CO_2$ incubator. For tube-$CO_2$, COCs were cultured in a round-bottom tube in a $CO_2$ incubator, and for tube-non-$CO_2$, COCs were cultured in a round-bottom tube sealed tightly without $CO_2$ supplement in a dry incubator. The proportion of oocytes reached to metaphase II (M-II) was not significantly different among three groups (87.9% to 91.4%). In experiment 2, we evaluated the effect of $CO_2$ non-supplement during oocyte maturation on development of embryos. Oocytes with a polar body were divided into two groups (Control and tube-non-$CO_2$) and applied 1.1 kV/cm or 1.2 kV/cm voltages for parthenogenetic activation. After activation, embryos were cultured for 6 days and examined the development. The proportion of embryos cleaved was not significantly different among treatment (86.3% to 91.5%). The proportion of embryo reached to blastocyst stage was not significantly different among treatment (13.9% to 25.2%). The cell number of blastocysts was not significantly different among treatment (29.0 to 32.4). In conclusion, oocytes cultured in a dry incubator without $CO_2$ supplement have enough competence to development after parthenogenetic activation. These results would be useful for transporting oocytes or embryos a long distance.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.163-164
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• 2018

• Archives of Plastic Surgery
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• v.43 no.6
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• pp.570-574
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• 2016

Background Fractional $CO_2$ laser is an effective treatment for scars, but most patients complain about sharp burning pain, even after the application of lidocaine ointment. This study analyzed the impact of a vibrating device to nonpharmacologically reduce the acute pain of laser treatment, in accordance with the gate control theory of pain management. Methods This is a prospective study performed from May 2013 through March 2014. Fifty-three patients (mean age, 26.7 years; range, 16-44 years) who had donated livers for liver transplantation were treated with a fractional $CO_2$ laser (10,600 nm; model $eCO_2$, Lutronic Corp) for their abdomen scars. Laser treatment was applied 4 months after surgery. A commercially available, locally applied vibrating device (model UM-30M, Unix Electronics Co. Ltd.) was used, in an on-and-off pattern, together with the $CO_2$ laser. A visual analogue scale (VAS; 0, no pain; 10, most severe pain) of pain sensation was assessed and statistically analyzed using a paired t-test. Results The average VAS score for pain with the vibrating device was 4.60 and the average VAS score without the vibrating device was 6.11. The average difference between scores was 1.51 (P=0.001). Conclusions A locally applied vibrating device was demonstrated to be effective in reducing pain when treating with a fractional $CO_2$ laser. Vibration treatment could be helpful when treating scars with fractional $CO_2$ laser in pain-sensitive patients, particularly children.

• Journal of the Korean Society for Heat Treatment
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• v.9 no.2
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• pp.79-90
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• 1996

Transmission electron microscopy(TEM) investigation on the phase decomposition of B2-ordered (Ni,Co)Al supersaturated with Ni and Co has revealed the precipitation of $(Ni,Co)_2Al$ which has not been expected from the reported equilibrium phase diagram. The $(Ni,Co)_2Al$ phase has a hexagonal struture and takes a rod-like shape with the long axis of the rod parallel to the <111> directions of the B2 matrix. By aging at temperatures below 873 K, a long period Superlattice Structure appears in the hexagonal $(Ni,Co)_2Al$ Phase. The orientation relationship between the $(Ni,Co)_2Al$ Precipitates and the B2-(Ni,Co)Al matrix is found to be$(0001)_p$ // $(111)_{B2}$ and $[\bar{1}2\bar{1}0]_P$ // $[\bar{1}10]_{B2}$, Where the suffix p and B2 denote the $(Ni,Co)_2Al$ precipitate and the B2-(Ni,Co)Al matrix, respectively. (Ni,Co)Al hardens appreciably by the fine precipitation of the $(Ni,Co)_2Al$ phase. Energy dispersive spectroscopy was used to analyze the compositions of each phase formed in B2-(Ni,Co)Al.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.148-152
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• 2009

Numerous studies have presented evidence that global atmospheric carbon dioxide ($CO_{2}$ ) concentration and temperature is increasing every year. Both of the $CO_{2}$ and temperature are important components for photosynthesis activity of plants and thusgrowth and yield. However, little information is available in terms of the reaction of vegetable plants to increased $CO_{2}$ concentration and temperature, and also the reaction to a complex condition of both increased $CO_{2}$ concentration and temperature. The aim of this research was therefore to investigate changes in growth, photosynthetic activity and ultra-cellular structure of leaf tissue of Chinese cabbage. Plants were grown under either of elevated $CO_{2}$ concentration (elevated $CO_{2}$, 2-fold higher than atmospheric $CO_{2}$ ) or elevated temperature (elevated temp, 4$^{\circ}C$ higher than atmospheric temperature), under both of elevated $CO_{2}$ concentration and elevated temperature (elevated temp+$CO_{2}$), and under atmospheric $CO_{2}$ concentration and temperature (control). The treatment of 'elevated temp' negatively affected leaf area, fresh weight, chlorophyll and starch content. However, when the treatment of 'elevated temp' was applied coincidently with the treatment of 'elevated $CO_{2}$', growth and photosynthetic performance of plants were as good as those in the treatment of 'elevated $CO_{2}$', Microscopic study resulted that the highest starch content and density of cells were observed in the leaf tissue grown at the treatment of 'elevated $CO_{2}$', whereas the lowest ones were observed in the leaf tissue grown at the treatment of 'elevated temp'. These results suggest that when Chinese cabbage grows under a high-temperature condition, supplement of $CO_{2}$ would improve the growth and yield. In our knowledge, it is the first time to determine the effect of a complex relationship between the increased $CO_{2}$ concentration and temperature on the growth of Chinese cabbage.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.169-180
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• 2012

Aster altaicus var. uchiyamae, endangered plants to grade II designated by the Ministry of Environment Korea, is only distributed in Gyeongsangbukdo, Chungcheongnamdo in Korea. In order to know the effects of elevated $CO_2$ concentration and temperature on ecological responses of A. altaicus var. uchiyamae, this study was carried out in the control(ambient $CO_2$ + ambient temperature) and treatment(elevated $CO_2$ + elevated temperature) at glasshouse. As a result, germination rate of A. altaicus var. uchiyamae was higher in control than in treatment. Period of alive leaf was longer in control than in treatment. Period of blooming and seed maturity was faster in control than in treatment. Shoot and root weight were heavier in control than in treatment. No. of inflorescence per plant and seed per inflorescence was higher in control than in treatment. Weight of inflorescence per plant, seed per inflorescence and one seed was heavier in control than in treatment. These results indicate that ecological responses of A. altaicus var. uchiyamae may be more negatively affected by elevated $CO_2$ and temperature except for phenological responses of that may be delayed under future global warming situation.