• 제목/요약/키워드: Oxide

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Evaluation of Greenhouse Gas Emissions in Cropland Sector on Local Government Levels based on 2006 IPCC Guideline (2006 IPCC 가이드라인을 적용한 지자체별 경종부문 온실가스 배출량 평가)

  • Jeong, Hyun-Cheol;Kim, Gun-Yeob;Lee, Seul-Bi;Lee, Jong-Sik;Lee, Jung-Hwan;So, Kyu-Ho
    • Korean Journal of Soil Science and Fertilizer
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    • 제45권5호
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    • pp.842-847
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    • 2012
  • This study was conducted to estimate the greenhouse gas emissions on local government levels from 1990 to 2010 using 2006 IPCC guideline methodology. To calculate greenhouse gas emissions based on the 16 local governments, emission factor and scaling factor were used with default value and activity data came from the food, agricultural, forestry and fisheries statistical yearbook of MIFAFF (Ministry for Food, Agriculture, Forestry, and Fisheries). The total emissions in crop sector gradually decreased from 1990 to 2010 due to a decline in agricultural land and nitrogen fertilizer usage. The annual average emission of greenhouse gas was the highest in Jeonnam (JN) with 1,698 Gg $CO_2$-eq and following Chungnam (CN), Gyungbuk (GB), Jeonbuk (JB) and Gyunggi (GG). The sum of top-six locals emission had occupied 83.4% of the total emission in cropland sector. The annual average emissions in 1990 by applying 2006 IPCC guideline were approximately 43% less than the national greenhouse gas inventory by 1996 IPCC guideline. Jeonnam (JN) province occupied also the highest results of greenhouse gas emission estimated by gas types (methane, nitrous oxide and carbon dioxide) and emission sources such as rice cultivation, agricultural soil, field burning of crop residue and urea fertilizer.

Volcanic stratigraphy and petrology of Cretaceous volcanic rocks in the eastern part of the Euiseong Basin (의성분지 동부에 분포하는 백악기 화산암류의 화산층서와 암석학적 연구)

  • 정종옥;좌용주
    • The Journal of the Petrological Society of Korea
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    • 제9권4호
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    • pp.238-253
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    • 2000
  • In the eastern part of the Euiseong Basin acidic~intermediate volcanic rocks widely distribute on the Cretaceous sedimentary basement. Coeval granitic rocks and dyke rocks intruded into the volcanic rocks. Volcanic stratigraphy of study area are andesite lava, dacitic lapilli tuff, dacitic flow-banded lava, rhyolitic bedded tuff, rhyolitic massive tuff, dacitic massive lava, rhyolitlc welded tuff occur from the lower to the upper strata. $SiO_2$ content of the volcanic rocks range from 51 to 74 wt.%. With the increase of $SiO_2$, the contents of $TiO_2$, $Al_2$$O_3$, MgO, FeOT MnO, CaO, $P_2$$O_{5}$ decrease but those of $K_2$O increase. The contents of $Na_2$O show dispersive variation. This trend is quite sim-ilar to the major oxide variation in the volcanic rocks from the Yucheon sub-basin. The geochemical natures indicate that the volcanic rocks in the study area are discriminated to the island-arc type high K to medium K calc-alkaline rocks. The compositional variation of the volcanic rocks can be explained by the plagioclase fractionation of the volcanic magmas originated from similar source materials. The volcanic stratigraphy seems to have formed by at least two eruptive sequences of andesitic to rhyolitic and dacitic to rhyolitic magmas which underwent crystallization differentiation.

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Effect of garlic (Allium sativum L.) stems on inflammatory cytokines, iNOS and COX-2 expressions in Raw 264.7 cells induced by lipopolysaccharide (Lipopolysaccharide로 유도된 Raw 264.7 세포에서 마늘대 추출물(Allium sativum L. Stems)의 염증성 사이토카인 및 iNOS, COX-2 발현에 대한 효과 검증)

  • Cho, Yong Hun;Kim, Hyeon Jeong;Kim, Dong In;Jang, Jae Yoon;Kwak, Jae Hoon;Shin, Yu Hyeon;Cho, Yeon Gje;An, Bong Jeon
    • Food Science and Preservation
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    • 제22권4호
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    • pp.613-621
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    • 2015
  • In this study, the anti-oxidant and anti-inflammatory activities of water extract (ASSW) and 70% ethanol extract (ASSE) of Allium sativum L. stems were investigated using Raw 264.7 cells induced by lipopolysaccharide (LPS). ABTS radical scavenging activities of ASSW and ASSE at $1000{\mu}g/mL$ concentration were 96.9% and 97.8%, respectively. In order to investigate the potential anti-inflammatory effects of ASSW and ASSE, nitric oxide (NO), pro-inflammatory cytokines, interleukin-6 (IL-6), and tumor necrosis factor including ${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), and prostaglandin-E2 (PGE2) were measured. ASSW and ASSE at $100{\mu}g/mL$ concentration showed inhibitory effects against NO production by 18% and 23%, respectively. Production of IL-$1{\beta}$ and IL-6 after treatment with ASSW and ASSE at $100{\mu}g/mL$ decreased by approximately 28% and 15% for ASSW and 17% and 12% for ASSE, respectively. In addition, production of TNF-${\alpha}$ after treatment of $100{\mu}g/mL$ of ASSW and ASSE decreased by 24% and 23%, respectively. In addition, the treatment of $100{\mu}g/mL$ of ASSW and ASSE showed inhibitory expressions against PGE2 by 45.47% and 33.87%, respectively. These results suggested that ASSE showed greater inhibitory activity than that of the ASSW by the suppression of inflammatory mediators, including NO, IL-6, TNF-${\alpha}$ and PGE2 production, and the expressions of iNOS and COX-2 in macrophages. In conclusion, ASSW and ASSE may have some ancillary effects on inflammatory factors as potential anti-inflammatory agents.

Protective effects of quality certified traditional Doenjang in Korea on TNF-α-induced vascular inflammation in human umbilical vein endothelial cells (혈관내피세포에서 TNF-α 자극에 의해 유도되는 혈관염증에 대한 전통식품 품질인증 된장의 효능 평가)

  • Kim, Eun-Ju;Jang, Yeon-Jeong;Kim, So-Young;Choi, Hye-Sun;Park, Shin-Young
    • Food Science and Preservation
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    • 제23권3호
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    • pp.378-386
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    • 2016
  • Anti-atherogenic effects in tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-stimulated human umbilical vein endothelial cells (HUVEC) are involved in the suppression of oxidative stress, cell adhesion molecules, and pro-inflammatory factors. This study investigated the vascular inflammation inhibitory activity of traditional Doenjang plays a key role in the pathogenesis and progression of atherosclerosis. The protective effects of Korean Deonjang was investigated on the expression of cell adhesion molecules (CAMs) in tumor necrosis factor (TNF)-${\alpha}$-induced human umbilical vascular endothelial cells (HUVECs). Deonjang extracts (20, 50, $100{\mu}g/mL$) decreased the expression of 20 ng/mL TNF-${\alpha}$-induced vascular cell adhesion molecule (VCAM)-1 intracellular adhesion molecule (ICAM)-1 proteins, and their corresponding mRNA levels. Nitric oxides (NO) produced by endothlial nitric oxides synthase (eNOS) dilated blood vessels, which had protective effects against platelet and leukocyte adhesion. While TNF-${\alpha}$-induced suppressed the production of nitric oxide in HUVECs, Doenjang restored NO production in HUVECs. In addition, Deonjang reduced the TNF-${\alpha}$-induced expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 mRNA levels. These results suggested that Doenjang can inhibited the production of cell adhesion molecules and inflammatory mediators, which could be a potential candidate for preventing atherosclerosis.

A Study on the Carbothermic Reduction and Refining of V, Ta and B Oxides by Ar/Ar-H2 Plasma (Ar/Ar-H2 플라즈마에 의한 V, Ta, B 산화물의 탄소용융환원 및 정련)

  • Chung, Yong-Sug;Park, Byung-Sam;Hong, Jin-Seok;Bae, Jung-Chan;Kim, Moon-Chul;Baik, Hong-Koo
    • Journal of Hydrogen and New Energy
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    • 제7권1호
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    • pp.81-92
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    • 1996
  • The Ar/Ar-$H_2$ plasma method was applied to reduce oxides and refine metals of V, Ta and B. In addition, the high temperature chemical reaction in Ar plasma and of the refining reaction in the Ar-(20%)$H_2$ plasma were analyzed. The crude V of 96wt% purity was obtained at the ratio of $C/V_{2}O_{5}=4.50$ by the Ar plasma reduction grade and the maximum reduction was obtained at $C/V_{2}O_{5}=4.50$ due to the $O_{2}$ loss from the thermal decomposition of vanadium oxide. In the Ar-(20%)$H_2$ plasma refining, the metallic V of 99.2wt% was produced at the ratio of $C/V_{2}O_{5}=4.40$. It was considered that a main refining reaction resulted from the chemical reaction between the residual carbon and residual oxygen. The metallic Ta of 99.8wt% was obtained at the ratio of $C/Ta_{2}O_{5}=5.10$ in a Ar plasma reduction and the Oz loss from the thermal decomposition of tantalum pentoxide did not take place. The deoxidation reaction was more significant than the decarburization reaction in the Ar-(20%)$H_2$ plasma refining and the metallic Ta of 99.9wt% was produced within the range of $C/Ta_{2}O_{5}$ ratio of 4.50 to 5.10. The Vickers hardness of Ta in the above mentioned range was about 220Hv due to the decrease in a residual oxygen by the deoxidation reaction. On the other hand, C is no suitable agent for the reduction of $B_{2}O_{3}$ by the Ar and Ar-$H_2$ plasma. But Fe-B-Si alloy was produced with the reduction of $B_{2}O_{3}$ in the melt when Fe, C, $B_{2}O_{3}$, and ferroboron mixtures were melted by the high frequency induction melting.

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CASE REPORTS OF TREATMENT OF ERUPTION-DISTURBED MX. FIRST MOLAR BY SURGICAL EXPOSURE (맹출 장애를 가진 상악 제1대구치의 외과적 노출을 이용한 치험례)

  • Seok, Choong-Ki;Nam, Dong-Woo;Kim, Hyun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • 제31권1호
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    • pp.11-18
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    • 2004
  • The eruption of permanent teeth represents the movement in the alveolar bone before appearance in oral cavity, to the occlusal plane after appearance in oral cavity, and additive movement after reaching th the occlusal plane. Tooth eruption is mostly controlled by genetic signals. The eruption stage is divided to preeruptive alveolar stage, alveolar bone stage, mucosal stage according to the process of growth and development. If the disturbance is occured in any stage of eruption, tooth does not erupt. The cause of eruption disturbance are ectopic position of the tooth germ, obstruction of the eruption path and defects in the follicle or PDL. In the treatment of eruption disturbance, surgical procedures are commonly used. There are three kind of surgical procedure ; surgical exposure, surgical repositioning, surgical exposure and traction Surgical exposure is basic procedure. This involves removal of mucosa, bone, lesion that are surrounding the teeth, dental sac when necessary to maintain a patent channel between the crown and the normal eruptive path into the oral cavity. To ensure this patency, many techniques including cementation of a celluloid crown, packing with gutta-percha or zinc oxide-eugenol, or a surgical pack, are used. When surgical exposure is conducted, operators should not expose any part of cervical root cement and not injure periodontium or root of adjunct tooth. After surgical exposure, tooth should be surrounded by keratinized gingiva. There is direct relationship between the extent of development of pathophysiologic aberrations and the intensity of the manipulative injury inflicted on the tooth by surgical treatment, so operator should consider this thing. In these cases, surgical exposure is conducted on Maxillary 1st milars that have a eruption disturbance and improve the eruption disturbance effectively.

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Electrochemical Characteristics of LiMn2O4 Cathodes Synthesized from Various Precursors of Manganese Oxide and Manganese Hydroxide (다양한 형태 및 구조의 망간산화물 및 망간수산화물 전구체로부터 합성한 LiMn2O4양극의 전기화학적 특성 연구)

  • Lee, Jong-Moon;Kim, Joo-Seong;Hong, Soon-Kie;Lee, Jeong-Jin;Ahn, Han-Cheol;Cho, Won-Il;Mho, Sun-Il
    • Journal of the Korean Electrochemical Society
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    • 제15권3호
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    • pp.172-180
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    • 2012
  • The $LiMn_2O_4$ cathodes for lithium ion battery were synthesized from various precursors of manganese oxides and manganese hydroxides. As the first step, nanosized precursors such as ${\alpha}-MnO_2$ (nano-sticks), ${\beta}-MnO_2$ (nano-rods), $Mn_3O_4$ (nano-octahedra), amorphous $MnO_2$(nano-spheres), and $Mn(OH)_2$ (nano-plates) were prepared by a hydrothermal or a precipitation method. Spinel $LiMn_2O_4$ with various sizes and shapes were finally synthesized by a solid-state reaction method from the manganese precursors and LiOH. Nano-sized (500 nm) octahedron $LiMn_2O_4$ showed high capacities of 107 mAh $g^{-1}$ and 99 mAh $g^{-1}$ at 1 C- and 50 C-rate, respectively. Three dimensional octahedral crystallites exhibit superior electrochemical characteristics to the other one-dimensional and two-dimensional shaped $LiMn_2O_4$ nanoparticles. After 500 consecutive charge discharge battery cycles at 10 C-rate with the nano-octahedron $LiMn_2O_4$ cathode, the capacity retention of 95% was observed, which is far better than any other morphologies studied in this work.

Effects of Jeju Citrus unshiu Peel Extracts Before and After Bioconversion with Cytolase on Anti-Inflammatory Activity in RAW264.7 Cells (면역세포에서 Bioconversion 전후 제주 감귤 과피 추출물의 항염증 효과)

  • Seo, Jieun;Lim, Heejin;Chang, Yun-Hee;Park, Hye-Ryeon;Han, Bok-Kyung;Jeong, Jung-Ky;Choi, Kyoung-Sook;Park, Su-Beom;Choi, Hyuk-Joon;Hwang, Jinah
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제44권3호
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    • pp.331-337
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    • 2015
  • Citrus and its peels, which are by-products from juice and/or jam processing, have long been used in Asian folk medicine. Citrus peels show an abundant variety of flavanones, and these flavanones have glycone and aglycone forms. Aglycones are more potent than glycones with a variety of physiological functions since aglycone absorption is more efficient than glycones. Bioconversion with cytolase converted narirutin and naringin into naringenin and hesperidin into hesperetin. Therefore, this study aimed to investigate the anti-oxidant and anti-inflammatory effects of bioconversion of Citrus unshiu (CU) peel extracts with cytolase (CU-C) in RAW264.7 cells. HPLC chromatograms showed that CU and CU-C had 23.42% and 29.39% total flavonoids, respectively. There was substantial bioconversion of narirutin to naringenin and of hesperidin to hesperetin. All citrus peel extracts showed DPPH scavenging activities in a dose-dependent manner, and CU-C was more potent than intact CU. RAW264.7 cells were pre-treated with $0{\sim}500{\mu}g/mL$ of citrus peel extracts for 4 h and then stimulated by $1{\mu}g/mL$ of lipopolysaccharide (LPS) for 8 h. All citrus peel extracts showed decreased mRNA levels and protein expression of LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner. Especially, CU-C markedly inhibited mRNA and protein expression of iNOS and COX-2 compared to intact citrus peel extracts. All citrus peel extracts showed decreased NO production by iNOS activity. This result suggests that bioconversion of citrus peel extracts with cytolase may provide potent functional food materials for prevention of chronic diseases attributable to oxidation and inflammation by boosting the anti-inflammatory effects of citrus peels.

Quality Characteristics and Antioxidant Activity of Prickly Pear Cactus Cladodes (손바닥 선인장 엽상경의 품질 특성과 항산화 효과)

  • Hwang, Joon-Ho;Yi, Mi-Ran;Kim, Jae-Won;Bu, Hee-Jung;Kang, Chang-Hee;Lim, Sang-Bin
    • Journal of the Korean Society of Food Science and Nutrition
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    • 제44권3호
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    • pp.356-362
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    • 2015
  • Prickly pear cactus cladodes were extracted with hot water and 70% ethanol, followed by fractionation with n-hexane (HF), ethyl acetate (EF), n-butanol (BF), and distilled water. Total phenolics and total flavonoid contents as well as antioxidative and anti-inflammatory activities were then measured. Total phenolic contents were 784, 452, and 220 mg gallic acid equivalents (GAE)/g, whereas total flavonoid contents were 214, 76, and 113 mg quercetin equivalents (QE)/g in EF, BF, and HF, respectively. DPPH and ABTS radical scavenging activities ($IC_{50}$) were 103 and $105{\mu}g/mL$ in EF, 359 and $379{\mu}g/mL$ in BF, and 469 and $605{\mu}g/mL$ in HF, respectively. Oxygen radical absorbance capacity was highest at $391{\mu}M$ TE in EF (in decreasing order of $117{\mu}M$ TE in BF and $64{\mu}M$ TE in HF), whereas superoxide anion radical scavenging activity ($IC_{50}$) was highest at $40{\mu}g/mL$ in EF (in decreasing order of $69{\mu}g/mL$ in BF and $98{\mu}g/mL$ in 70% ethanol extract). Inhibitory activity ($IC_{50}$) of nitric oxide (NO) production induced by LPS-activated RAW264.7 cells was highest at $62{\mu}g/mL$ in HF (in decreasing order of $104{\mu}g/mL$ in EF and $465{\mu}g/mL$ in BF). The selectivity index (ratio of inhibitory activity of NO production to cell cytotoxicity) was highest at 4.63 in EF (in decreasing order of 3.37 in HF and 2.14 in BF). In conclusion, EF showed potent antioxidant and anti-inflammatory effects with high phenolic and flavonoid contents.

Mechanical properties of $Al_2O_3/Mo/MnO_2$ composite ($Al_2O_3/Mo/MnO_2$ 복합재료의 기계적 특성)

  • Park, Hyun;Kim, Kyung-Nam
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • 제16권4호
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    • pp.172-179
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    • 2006
  • When $Al_2O_3-MoO_3$ mixture is reduced, $MoO_3$ is only reduced to Mo at $900^{\circ}C$. But a compound between $Al_2O_3$ and Mo is not formed up to $1300^{\circ}C$. In the case of $Al_2O_3-MoO_3-MnO_2$ mixture, an intermediate compound $Mn_2Mo_3O_8$ is firstly formed at $900^{\circ}C$ and changes to $MnAl_2O_4$ at $1100^{\circ}C{\sim}1300^{\circ}C$. $Al_2O_3/Mo/MnO_2$ composite are manufactured by a selective reduction process in which Mo is only reduced in the powder mixture of $Al_2O_3,\;MoO_3\;and\;MnO_2$ oxide. For $Al_2O_3/Mo$ composite, the average grain size was not changed with increasing Mo content because of inhibition of grain growth of $Al_2O_3$ matrix in the presence of Mo particles. Fracture strength increased with increasing Mo content due to phenomenon of grain growth inhibition of $Al_2O_3$ matrix. Hardness decreased because of a lower hardness value of Mo, whereas fracture toughness increased. For $Al_2O_3,\;Mo\;and\;MnO_2$ composite, grain growth was facilitated by MnOB and it showed a lower fracture strength because of grain growth effect with increasing Mo and $MnO_2$ content. Hardness decreased because of the grain growth of matrix and coalesced Mo particles to be located in grain boundary, whereas fracture toughness increased.