• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.894-900
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• 2001

The spinel $Li{Mn_2}{O_4}$ catalysts for $CO_2$ decomposition were synthesized by a sol-gel method using manganese acetate and lithium hydroxide as starting materials through drying at $150^{\circ}C$ for 12 hrs under oxygen atmosphere followed by heat treatment at $480^{\circ}C$ for 12 hrs. The synthesized $Li{Mn_2}{O_4}$ were reduced by hydrogen for 3 hrs at various temperatures and the decomposition rate of carbon dioxide was investigated at 300, 325, 350, 375 and $400^{\circ}C$ using the $Li{Mn_2}{O_4}$ reduced by hydrogen gases. As a result of experiment, the optimum temperature of hydrogen reduction and $CO_2$ decomposition was shown $350^{\circ}C$. The physicochemical properties of the spinel $Li{Mn_2}{O_4}$ the reduced $Li{Mn_2}{O_4}$ and the $Li{Mn_2}{O_4}$ after $CO_2$ decomposition were examined with XRD, SEM and TGA.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.3
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• pp.1-12
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• 2012

Objectives : Fagopyrum esculentum(FE) has been used for removal of inflammation of internal organs and treatment of sore and ulcer by heat toxin in Korean herbal medicines. In this study, To investigated the protective effect of FE on allergic response, we determined whether FE inhibits allergic response. Methods : The effect of FE was analyzed by ELISA, RT-PCR and Western blot in RBL-2H3 cells. We investigated cell viability, ${\beta}$-hexosaminidase, as a marker of degranulation, cytokne, and intracellular ROS and MAPK and NF-${\kappa}B$ signaling. Results : We found that FE suppressed ${\beta}$-hexosaminidase release, the production of IL-4 and TNF-${\alpha}$ and intracellular ROS level in RBL-2H3 by the anti-DNP IgE plus DNP-HSA stimulation. FE also significantly inhibited cytokine mRNA expressions, such as IL-$1{\beta}$, IL-2, IL-3, IL-4, IL-5, IL-6, IL-13, TNF-${\alpha}$ and GM-CSF in RBL-2H3. In addition, PF suppressed the phospholyation of ERK1/2, JNK1/2, p38 and $I{\kappa}B{\alpha}$ and NF-${\kappa}B$ signal transduction pathway. Conclusions : Our results indicate that FE protects against allergic response and exerts an anti-inflammatory effect through the inhibition of degranulation and production of cytokines and ROS via the suppression MAPK and NF-${\kappa}B$ of signal transduction. Abbrevations : FE, Fagopyrum esculentum; RBL-2H3, rat basophilic leukemia cell line; ROS, reactive oxygen species; MAPK, Mitogen-activated protein kinase; $NF{\kappa}B$, nuclear factor ${\kappa}B$; $TNF{\alpha}$, Tumor necrosis factor alpha; GM-CSF, Granulocyte macrophage colony-stimulating factor; ERK, extracellular-signal-regulated kinase; JNK, c-Jun NH2-terminal kinase; p38, p38 MAP kinase; $I{\kappa}B{\alpha}$, inhibitory-kappa B alpha.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.55-65
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• 2002

Ginseng has been used as a key constituent in traditional medicine prescriptions for centuries. Other than its well-known anti-stress and adaptogenic properties, ginseng has also been shown to be very effective in treating age-related deterioration in metabolic and memory functions. Although it is generally believed that the saponin (GS) fraction of the ginseng root accounts for the bioactivity of ginseng, a direct demonstration on which ginsenoside does what is still generally lacking. In the past decade, our laboratory has endeavored to identify the active GS components involved in energy metabolism, memory, and anti-neurotoxicity. To examine the ergogenic effects of GS in enhancing aerobic capacity, rats were subjected to either severe cold ($40^{\circ}C$ under helium-oxygen, two hours) or exercise workload $(70\%\;VO_{2}max,$ to exhaustion). Acute systemic injection (i.p.) of ginseng GS (5-20 mg/kg) significantly elevated both the total and maximum heat production in rats and improved their cold tolerance. However, pretreating the animal with the optimal dose (10 mg/kg) of GS devoid of $Rg_1\;and\;Rb_1$ failed to elicit any beneficial effects in improving cold tolerance. This indicates that either $Rb_1\;and/or\;Rg_1$ may be essential in exemplifying the thermogenic effect of GS. Further studies showed that only pretreating the animals with $Rb_1(2.5-5\;mg/kg),\;but\;not\;Rg_l,$ resulted in an increase in thermogenesis and cold tolerance. In contrast to the acute effect of GS on cold tolerance, enhancement of exercise performance in rats was only observed after chronic treatment (4 days). Further, we were able to demonstrate that both $Rb_1\;and\;Rg_1$ are effective in enhancing aerobic endurance by exercise. To illustrate the beneficial effects of GS in learning and memory, a passive avoidance paradigm (shock prod) was used. Our results indicated that the scopolamineinduced amnesia can be significantly reversed by chronically treating (4 days) the rats with either $Rb_1\;or\;Rg_1$ (1.25 - 2.5 mg/kg). To further examine its underlying mechanisms, the effects of various GS on ${\beta}-amyloid-modulated$ acetylcholine (ACh) release from the hippocampal slices were examined. It was found that inclusion of $Rb_1$ (0.1 ${\mu}M$), but not $Rg_1$, can attenuate ${\beta}-amyloid-suppressed$ ACh release from the hippocampal slices. Our results demonstrated that $Rb_1\;and\;Rg_1$ are the key components involved in various beneficial effects of GS but they may elicit their effects through different mechanisms.

• Food Science and Preservation
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• v.25 no.1
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• pp.98-106
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• 2018

Portulaca oleracea L., a species of Portulacaceae, is ubiquitous. It is a well-known traditional Chinese medicine for removing heat, counteracting toxicity, cooling blood, and maintaining hemostasia; it is also used as antidysentery agent. This study investigated the anti-oxidative and anti-inflammatory activities of water and ethanol extracts from P. oleracea. The total polyphenol content ($21.08{\pm}0.03mg\;GAE/g$) and total flavonoid content ($5.45{\pm}0.76mg\;QE/g$) of the ethanolic extracts were higher than those of the water extracts. The antioxidative activities were determined by evaluating the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and by the ferric reducing antioxidant potential (FRAP) assay. The ABTS radical scavenging activity of the water extract (75.53%) was higher in those of the water extract (67.03%) at concentration of $1,000{\mu}g/mL$. The DPPH radical scavenging activity and FRAP of the ethanol extract were higher than those of the water extract. We also investigated the anti-inflammatory activity of the P. oleracea extracts in LPS-stimulated Raw 264.7 cells. The production levels of nitric oxide (NO) and reactive oxygen species (ROS) significantly decreased with an increasing concentration of the extract. The expression levels of pro-inflammatory cytokines (tumor necrosis faction (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$, and IL-6) were significantly lower in the ethanol extract than in the LPS alone treatment group. Based on these results, ethanolic extract from P. oleracea could be an effective antioxidant and anti-inflammatory agent.

• Korean Journal of Materials Research
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• v.5 no.7
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• pp.880-887
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• 1995

Melt spun YB $a_2$C $u_3$A $g_{15}$ and YbB $a_2$C $u_3$A $g_{x}$(x=5, 16 and 53) precursor alloy ribbons were oxidized at 263~322$^{\circ}C$, and heat-treated at 872~89$0^{\circ}C$ under 1.0atm oxygen pressure. In addition, about ten ribbons were stacked and coupled by pressing, and then followed the same heat treatment. YB $a_2$C $u_3$ $O_{7-{\delta}}$(1-2-3) or YbB $a_2$C $u_3$ $O_{7-{\delta}}$(1-2-3) phase was formed in both the ribbons and the multilayered specimens. The formed 1-2-3 phases were not texturized in all the ribbons, but slightly texturized in the multilayered specimens. $J_{c}$ was not achieved in all the ribbons at 77K and zero magnetic field. Among the multilayered specimens, YB $a_2$C $u_3$A $g_{15}$ and YbB $a_2$C $u_3$A $g_{16}$ showed $J_{c}$ of 260 and 180A/$\textrm{cm}^2$, respectively. YB $a_2$C $u_3$A $g_{15}$ and YbB $a_2$C $u_3$A $g_{16}$ are considered to be the appropriate compositions in producing textured superconducting oxides with improved $J_{c}$ by pressing. Onset critical temperature ( $T_{on}$ ) of the multilayered YB $a_2$C $u_3$A $g_{15}$ was 92K while those of YbB $a_2$C $u_3$A $g_{x}$(x=5 , 16 and 53) were 88~90K. , 16 and 53) were 88~90K.

• Clean Technology
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• v.28 no.2
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• pp.131-137
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• 2022

The semiconductor process currently emits various by-products and unused gases. Emissions containing pollutants are generally classified into categories such as organic, acid, alkali, thermal, and cabinet exhaust. They are discharged after treatment in an atmospheric prevention facility suitable for each exhaust type. The main components of organic exhaust are volatile organic compounds (VOC), which is a generic term for oxygen-containing hydrocarbons, sulfur-containing hydrocarbons, and volatile hydrocarbons, while the main components of alkali exhaust include ammonia and tetramethylammonium hydroxide. The purpose of this study was to determine the combustion characteristics and analyze the NO_X reduction rate by maintaining a direct combustion and temperature to process organic and alkaline exhaust gases simultaneously. Acetone, isopropyl alcohol (IPA), and propylene glycol methyl ether acetate (PGMEA) were used as VOCs and ammonia was used as an alkali exhaust material. Independent and VOC-ammonia mixture combustion tests were conducted for each material. The combustion tests for the VOCs confirmed that complete combustion occurred at an equivalence ratio of 1.4. In the ammonia combustion test, the NO_X concentration decreased at a lower equivalence ratio. In the co-combustion of VOC and ammonia, NO was dominant in the NO_X emission while NO₂ was detected at approximately 10 ppm. Overall, the concentration of nitrogen oxide decreased due to the activation of the oxidation reaction as the reaction temperature increased. On the other hand, the concentration of carbon dioxide increased. Flameless combustion with an electric heat source achieved successful combustion of VOC and ammonia. This technology is expected to have advantages in cost and compactness compared to existing organic and alkaline treatment systems applied separately.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.3
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• pp.249-258
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• 2018

Airborne pollution causes oxidative damage, inflammation, and premature aging of skin. Resveratrol is a polyphenol compound that has various biological activities such as antioxidant, anti-inflammation, and anti-melanogenic activities but it is unstable to heat and light. Resveratryl triacetate (RTA) is a new cosmetic ingredient that is more stable than resveratrol and its skin safety and whitening efficacy have been reported previously. The purpose of this study was to examine the effects of resveratrol and resveratryl triacetate (RTA) on the inflammatory responses of human epidermal keratinocytes (HEKs) exposed to airborne particulate matters with a diameter of < $10{\mu}m$ (PM10). Cultured HEKs were exposed to PM10 in the absence or presence of resveratrol and RTA. Assays were undertaken to determine cell viability, the production of reactive oxygen species (ROS), and the expression of inflammatory cytokines. PM10 treatment decreased cell viability, and increased the expression of pro-inflammatory cytokines such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), $interleukin-1{\beta}$ ($IL-1{\beta}$), interleukin-6 (IL-6), and interleukin-8 (IL-8). Resveratrol and RTA reduced cell death and ROS production induced by PM10. PM10-induced mRNA expression of the inflammatory cytokines was either attenuated (IL-6), or enhanced ($IL-1{\beta}$), or unaffected ($TNF-{\alpha}$ and IL-8) by resveratrol and RTA. PM10-induced IL-6 protein expression was attenuated by resveratrol and RTA. This study suggests that resveratrol and RTA have activities regulating cell damage and inflammatory responses of the skin exposed to airborne particulate matters.

• Archives of design research
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• v.17 no.4
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• pp.241-250
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• 2004

In this research, the copper alloy plates C2200, C5210, C7701, C8113 were selected to make datum and to identify further usage of metal craft experimentation. For its experimentation, the general welding and TIG welding methods were researched; for 2nd experimentation, the Reticulation and Electroforming skill's differences in color and temperature were researched. With these methods 3 different kinds of works are introduced for sample studies. For this research, Dr. Lee, Dong-Woo who works in Poongsan Metal Co, supported 4 kinds of copper alloy metals. Which are Commercial bronze (Cu-Zn), Deoxidiged Copper(Cu-Sn-P), Nickel Silver (Cu-Ni-Zn), and White Bronze (Cu-Ni); they were applied partly and wholly by the method of Laminatin, Reticulation, Fusing, and Electroforming skills. In case of C2200, the brass, the A. C. TIG welding method is better under 2mm slight plate; the D.C. TIG welding is better upper 2mm plate; and 250~300$^{\circ}C$ is recommended for remain heat treatment. In case of C5210, not having Hydrogen in high temperature return period, doesn't need Oxygen in high temperature and hardening in comparative high temperature neither, it is good for welding. It contains Sn 2-9% ad P 0.03-0.4% generally; and in accordance with the growth rate of Sn contain amount, the harden temperature boundary become broad. In case of cold moment after welding, they are recommended that higher speed TIG welding, smaller melting site and less than 200$^{\circ}C$ for pre-heating temperature. In case of C7701, the 10-20% Ni, 15-30% Zn are widely used.. If it is upper 30% Zn, it become (${\alpha}+{\beta}$) system and adhesive power rate become lower, and the productivity become lower in low temperature but the productivity become higher in high temperature. Nickel Silver's resistance of electricity is well; and the heatproof and incorrodibility is good, too. Lastly, in case of C8113, good at persistence in salty and grind; high in strength of high temperature. In case of white brass, contain 10-30% Nickel and hardened in high temperature and become single phrase. For these reason, the crystallization particles easily become large, if the resistance become higher small amount of Pb, P, S separation rate become higher.