• Title/Summary/Keyword: H₂O₂

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Application Rate Modification of Paddy Herbicide Quinclorac Depending on Different Cultural Patterns (벼 작부양식(作付樣式)의 차이(差異)에 따른 제초제(除草劑) QUINCLORAC 의 선택활성(選擇活性) 변동(變動))

  • Guh, J.O.;Im, W.H.;Han, S.U.;Kuk, Y.I.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.124-131
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    • 1992
  • Not only reducing the carry-over effects of quinclorac [3, 7-dichloro-8-quinoline carboxylic acid] used in paddy field to some following vegetable crops but also rationalizing agro-ecology conservation and farm economy, the reducing feasibility of application rates by various cropping patterns and application timing after rice seeding and transplanting. Four cropping patterns namely dry direct seeding(DDS), flooded direct seed(FDS), transplanting of 8 days old early seedlings(EST) and 25 days old machinery seedling(MST) were experimented with 7 application timings as 0, 5, 10, 15, 20, 25, 30 days after seeding/transplanting and 9 levels of application rates as 0, 75, 150, 225, 300, 375, 450, 525, and 600g ai/ha of the chemical, respectively. Within the maximum permitted limit of rice phytotoxicity, the minimum application rate of quinclorac to complete control of Echinochloa crus-galli as influenced by various cropping patterns with application timing could be evaluated as follows : A. Dry direct seeding : The minimized application rate at application timing upto 10 days after seeding (DAS) was counted 150g ai/ha, and delaying upto 15-30 DAS, the rates were increased upto 225-525g ai/ha. B. Flooded direct seeding and transplanting : The application rates were minimized 75g ai/ha at application timing upto 10 days after seeding/transplanting(DAS/T), 150g ai/haupto 15 DAS/T, and 225g ai/ha at later than 20 DAS/T, respectively.

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Effects of Tested Pack Containing Plant Extracts on Elasticity and Size of Women's Breasts (식물추출물 팩의 여성가슴 탄력증진과 크기증대에 관한 연구)

  • Choi, Yea-Hun;Park, Min-Kyung;Kim, Yong-Gyun;Lee, Sang-Mong;Son, Hong-Joo;Park, Hyean-Cheal;Kim, Sun-Tae;Choi, In-Soo;Kim, Keun-Ki
    • Journal of Life Science
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    • v.22 no.3
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    • pp.407-416
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    • 2012
  • In this study, we purified the extracts from the seeds and the roots of various plant species, including Q. acutissima, C. lanceolata, P. mirifica, P. bambusoides, and S. repens, and then investigated the effects of these extracts on cell growth and fat accumulation in adipocytes. We found that the extracts purified from Q. acutissima, C. lanceolata, P. mirifica, P. bambusoides, and S. repens more effectively increased the cell growth, as well as promoting the fat accumulation in adipocytes to a greater extent, than other extracts in vitro. Therefore, we made breast packs containing these effective extracts, and then investigated whether they were effective in enhancing the elasticity and volume of women's breasts. The measurements of breast elasticity and size revealed that the breast packs efficiently increased the elasticity and size of women's breasts. Furthermore, evaluation of the questionnaires related to usage of the breast packs indicated great satisfaction in terms of the lift, firmness, and elasticity of breasts. In conclusion, extracts purified from Q. acutissima, C. lanceolata, P. mirifica, P. bambusoides, and S. repens leading to cell growth and fat accumulation in adipocytes can effectively contribute to improving the elasticity and size of women's breasts.

A Study on Oxygen Reduction Reaction of PtM Electrocatalysts Synthesized by a Modified Polyol Process (수정된 폴리올 방법을 적용하여 합성한 PtM 촉매들의 산소환원반응성 연구)

  • Yang, Jongwon;Hyun, Kyuwhan;Chu, Cheunho;Kwon, Yongchai
    • Applied Chemistry for Engineering
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    • v.25 no.1
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    • pp.78-83
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    • 2014
  • In this research, we evaluated the performance and characteristics of carbon supported PtM (M = Ni and Y) alloy catalysts (PtM/Cs) synthesized by a modified polyol method. With the PtM/Cs employed as a catalyst for the oxygen reduction reaction (ORR) of cathodes in proton exchange membrane fuel cells (PEMFCs), their catalytic and ORR activities and electrical performance were investigated and compared with those of commercial Pt/C. Their particle sizes, particle distributions and electrochemically active surface areas (EAS) were measured by TEM and cyclic voltammetry (CV), while their ORR activity and electrical performance were explored using linear sweeping voltammetries with rotating disk electrodes and rotating ring-disk electrodes as well as PEMFC single cell tests. TEM and CV measurements show that PtM/Cs have the compatible particle size and EAS with Pt/C. When it comes to ORR activity, PtM/C showed the equivalent or better half-wave potential, kinetic current density, transferred electron number per oxygen molecule and $H_2O_2$ production(%) to or than commerical Pt/C. Based on results gained by the three electrode tests, when the PEMFC single cell tests were carried out, the current density measured at 0.6 V and maximum power density of PEMFC single cell adopting PtM/C catalysts were better than those adopting Pt/C catalyst. It is therefore concluded that PtM/C catalysts synthesized by modified polyol can result in the equivalent or better ORR catalytic capability and PEMFC performance to or than commercial Pt/C catalyst.

Studies on the Determinations of Dissolved Oxygen in Beverages (음료중 산소분석법에 관한 연구)

  • Lee, Tal-Soo;Lee, Young-Ja;Kwon, Yong-Kwan;Park, Jae-Seok;Hwang, Jung-Yun;Lee, Ju-Yeun;Song, Jee-Won;Chung, Bo-Yong;Lee, Chul-Won
    • Korean Journal of Food Science and Technology
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    • v.34 no.3
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    • pp.361-364
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    • 2002
  • This study was performed to establish a simple and accurate method for the determination of oxygen that is a processing aid in various beverage. The quantitative determination of dissolved oxygen (DO) contents in 30 cases of samples were performed by traditional titration method and polarography. As a result of the study, the analysis of DO contents in fruit-extract beverages containing oxygen by titration method was time consuming and large sample volumes were needed. Besides, serious interferences with compounds such as hydroxylamine and nitric oxide were observed, leading to false response. Although the polarography is easily affected by $H_2S$, proteins, and various organic compounds, it is a simple and practical method that provides inexpensive and relatively rapid analysis. The polarography is best suited to the routine determination of DO in a large number of samples and it is expected that the polarography can directly be applied to the quality control of the beverages containing added oxygen. The analysis results of DO contents in various fruit-extract beverages with oxygen and without oxygen were as follows: 23.10 ppm to 32.60 ppm for various frutis extract beverages with oxygen, 0.70 pp to 2.54 ppm for mixed beverages without oxygen, 7.63 ppm to 8.28 ppm for drinking water.

Comparison of Antioxidant Activities of Enzymatic and Methanolic Extracts from Ecklonia cava Stem and Leave (감태(Ecklonia cava) 줄기 및 잎의 효소적 추출물과 메탄올 추출물에 의한 항산화 활성비교)

  • Lee, Seung-Hong;Kim, Kil-Nam;Cha, Seon-Heui;Ahn, Gin-Nae;Jeon, You-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.9
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    • pp.1139-1145
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    • 2006
  • In this study, antioxidant activities of enzymatic and methanolic extracts from E. cava stem and leave were evaluated by measuring the scavenging activities on 1,1 diphenyl 2 picrylhydrazyl (DPPH), hydroxyl radical, hydrogen peroxide and the inhibitory effects on DNA damage induced by oxidative stress of cells. Enzymatic extracts were prepared by enzymatic hydrolysis of both stem and leave using food grade five different carbohydrases (Viscozyme, Celluclast, AMG, Termamyl, Ultraflo) and five proteases (Protamex, Kojizyme, Neutrase, Flavourzyme, Alcalase). The enzymatic extracts were lower than methanolic extracts in polyphenol contents, but higher in extraction yield by approximately 30%. The enzymatic extracts were superior to methanolic extracts in DPPH and H2O2 scavenging activities and DNA damage protective effect. There were no significant antioxidant activity difference between stem and leave, but the extracts of leave were relatively better than those of stem. In this study it is suggested that E. cava stem as well as its leave would be a good raw materials for antioxidants compound extraction and enzymatic hydrolysis would be a good strategy to prepare antioxidant extracts from seaweeds.

Comparison of antioxidant capacity of protein hydrolysates from 4 different edible insects (식용곤충별 단백가수분해물의 항산화 활성 비교)

  • Jang, Hyun-Young;Park, Chae-Eun;Lee, Syng-Ook
    • Korean Journal of Food Science and Technology
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    • v.51 no.5
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    • pp.480-485
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    • 2019
  • The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

Physicochemical characteristics and physiological activities of mixture extracts from Liriope platyphylla, Schizandra chinensis, and Panax ginseng C.A. Meyer (맥문동, 오미자 및 인삼 혼합추출물의 이화학적 특성 및 생리활성)

  • Gu, Yul-Ri;Hong, Joo-Heon
    • Food Science and Preservation
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    • v.24 no.3
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    • pp.431-439
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    • 2017
  • This study was conducted to examine the antioxidant activities and physiological activities of mixture extracts (Liriope platyphylla, Schizandra chinensis and Panax ginseng C.A. Meyer) with different extraction mixing ratios (MEC, 2:1:1; ME1, 1:2:1; ME2, 1:1:2; ME3, 1.34:1.33:1.33). The yield of extracts ranged from 25.33 to 33.87%. The total polyphenol and total flavonoid contents of ME1 extracts were 1.01 g/100 g, 0.07 g/100 g, respectively. The total sugar contents of MEC extract was 22.83 g/100 g, respectively. The DPPH and ABTS radical scavenging activities of ME1 extracts at $1,000{\mu}g/mL$ were 26.79% and 21.08%. The superoxide radical scavenging and ferric-reducing antioxidant power of ME1 extracts at $1,000{\mu}g/mL$ were 67.83% and $295.47{\mu}M$, respectively. The functionalities of extracts were investigated with L-132 and RAW264.7 cell lines. The extracts on different mixing ratios did not show the toxicity on L-132 and RAW264.7 cell line in $100-2,500{\mu}g/mL$. The ME1 extract of $1,000{\mu}g/mL$ performed better than other extracts protective effects against oxidative stess in L-132 cells (81.22%) and the ME2 extract at $1,000{\mu}g/mL$ decreased nitric oxide production by $7.48{\mu}M$ which was more potent than other extracts. There results suggest that the ME1 extracts may be a useful functional food material in the food industry.

Study on the Influence of Ca and Mg Saturation Ratios of Soil on the Uptake of Ca, Mg, and K by Rice Plant (답토양(畓土壤)의 Ca, Mg 포화비(飽和比)가 수도(水稻)의 Ca, Mg, K의 흡수(吸收)에 미치는 영향(影響))

  • Jeong, Y.G.;Hong, J.W.;Ha, H.S.
    • Korean Journal of Soil Science and Fertilizer
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    • v.20 no.2
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    • pp.115-121
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    • 1987
  • A pot experiment was conducted to investigate the influence of Ca and Mg saturation ratios of soil on the uptake of Ca, Mg and K by rice plant. A silty loam soil was treated with $CaCl_2$ and $MgCl_2$ to obtain different degrees of Ca and Mg saturation. The studied ranges of Ca and Mg saturation ratios were 81:19, 70:30, 52:48, 55:45, and 31:69 in terms of the ratio of exchangeable Ca and Mg. Two levels of K application (90kg/ha, and 180kg/10a as $K_2O$) were also included in this study. The significant observation were summarized as follows. 1. When the Ca saturation of soil was dominant over Mg, the soil solution contained more Ca than Mg and vice versa. These led to the higher uptake of Ca by rice plant in Ca dominant soils and higher uptake of Mg in Mg dominant soils. 2. When the Ca and Mg saturation ratio was about equal, more Mg was released to soil solution leading to higher concentration of Mg in rice plant compare to that of Ca. 3. A trend was observed that the concentration of K in soil solution was lower in Mg dominant soils than in Ca dominant soils. This also resulted in the depressed uptake of K by rice plant under Mg dominant system when compare to Ca dominant system. 4. The increase application of K led to the increase in relative concentration of K to (Ca+Mg+K), and to the depression of divalent uptake by rice plant. However, it was observed that the degree of depression in uptake divalent by K application was more sensitive in case of Mg than that of Ca. 5. When viewed from grain yield of rice, it is pointed out that the optimum range of Ca to Mg ratio in soil may fall in the vicinity of 7:3. 6. Although K uptake by rice plant was influenced by the term of $AK^+/{\sqrt{A(Ca^{{+}{+}}+Mg^{{+}{+}})$ in soil solution, $AK^+$ itself was affected by the ratios of Ca:Mg in soil, as it were $AK^+$ value was decreased in Mg dominant soil than in Ca.

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Augustin und die Rhetorik (아우구스티누스와 수사학)

  • Hahn, Seok-whan
    • Journal of Korean Philosophical Society
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    • v.116
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    • pp.389-410
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    • 2010
  • Augustin wurde sozusagen von der Rhetorik zum Christentum bekehrt. Der einstmalige Rhetorikprofessor (bis 386) distanziert sich von seiner $fr{\ddot{u}}heren$ Kunst. Aber er $kn{\ddot{u}}pft$ als Bischof im vierten Buch seiner weniger bekannten Schrift "De doctrina Christiana" (DDC; abgef. 427) wieder an die antike Rhetorik, speziell an Cicero, an. So wird die augustinische $Sp{\ddot{a}}tschrift$ $f{\ddot{u}}r$ eine antike Rhetorik in christlicher Verwendung gehalten. Es stellt nun die Frage, was Augustin zur $R{\ddot{u}}ckkehr$ zu seiner $fr{\ddot{u}}heren$ Kunst bewegte. Neuere Forschungen sehen in Augustins Werk eine Grundlage der mittelalterlichen Predigttheorie oder einen $blo{\ss}en$ Versuch, die Rhetorik vom Makel des Sophistischen zu befreien. Gewiss ist seine Einstellung zur "leeren Beredsamkeit" der Sophistik eindeutig, aber dies war eine Haltung, die letztlich von allen seinen christlichen Zeitgenossen geteilt wurde und folglich eines geringen Beweises bedurfte. Die Aufmerksamkeit, die Augustins $sp{\ddot{a}}terem$ Einfluss und seiner Ablehnung der Zweiten Sophistik geschenkt wird, kann den Blick $tr{\ddot{u}}ben$ $f{\ddot{u}}r$ seine Rolle bei der $L{\ddot{o}}sung$ eines christlichen Dilemmas aus dem vierten Jahrhundert. Augustin sah die Gefahren einer entgegengesetzten rhetorischen $H{\ddot{a}}resie$. Die $S{\ddot{u}}nde$ des Sophisten besteht darin, dass er die Notwendigkeit des Inhalts verneint und glaubt, nur die forma alleine sei $w{\ddot{u}}nschenswert$. Der gegenteilige Fehler, dem Geschichtsschreiber der Rhetorik niemals einen Namen gegeben haben, beruht auf dem Glauben, dass derjenige, der im Besitz der Wahrheit ist, auch ipso facto in der Lage ist, die Wahrheit anderen zu ${\ddot{u}}bermitteln$. Es handelt sich um eine $ausschlie{\ss}liche$ $Abh{\ddot{a}}ngigkeit$ von der materia. Augustin erkannte eine Gefahr und benutzte DDC dazu, eine Verbindung von Inhalt und Form in der christlichen Predigt voranzutreiben. Nur wenn man daher das Buch als einen Teil der $gro{\ss}en$ Debatte des vierten Jahrhunderts ansieht, tritt seine historische Bedeutung klar hervor. Der Leser ist beeindruckt davon, dass der Autor darauf insistiert, es sei eine Torheit, dem Feind ein $n{\ddot{u}}tzliches$ Instrument zu ${\ddot{u}}berlassen$. Augustin $erkl{\ddot{a}}rt$, dass die Kunst der Beredsamkeit rege in Gebrauch genommen und nicht kurzerhand abgelehnt werden solle, weil sie mit dem Makel des Heidentums behaftet sei. Kurz gesagt, geplant ist das vierte Buch von DDC als eine ratio eloquentiae Christianae.

Effect of Kluyvera sp. CL-2 on Sugar contents of Watermelon and Soil Chemical Properties (유용미생물(Kluyvera sp. CL-2) 처리가 수박의 유리당 함량 및 토양화학성에 미치는 영향)

  • Hong, Soo-Young;Choi, Seong-Chul;Seo, Young-Ho;Lim, Su-Jeong;Heo, Su-Jeong;Yoon, Byeong-Sung;Park, Young-Hak;Hong, Dae Ki;Song, Jae-Kyeong
    • Korean Journal of Organic Agriculture
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    • v.26 no.4
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    • pp.677-686
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    • 2018
  • This study was carried out to determine the effect of Kluyvera sp. CL-2 (KACC 91283P) on the growth of watermelon (Citrullus vulgaris L.). The study consisted of three treatments, no treatment (NT), twice application of Kluyvera sp. CL-2 before transplanting (KC1), and five times application around transplanting (KC2). We determined the chemical properties of soil before and after the treatments, and compared the growth characteristics of watermelon among treatments. The treatment of Kluyvera sp. CL-2 at $1.0{\times}10^6cfu\;mL^{-1}$ significantly increased available $P_2O_5$. The organic matter showed to increase for all treatments, while soil pH, exchangeable Ca and Mg tended to decrease for all treatments. The leaf width was increased by 11.6% for KC1 and 26.2% for KC2 compared to NT. But there were no significant differences in yield, leaf length, fruit weight, fruit length, fruit width, and pericarp thickness among treatments. The contents of free sugars such as fructose and glucose were increased by microbial treatments but sucrose was not different from NT. The content of glucose in watermelon was increased by 13.8% in KC1 and 12.8% in KC2 compared to NT. The content of fructose increased by 14.6% in KC1 and by 39.8% in KC2 compared to NT. The results from the study imply that Kluyvera sp. CL-2 can be used to increase sugar content in watermelon.