• Title/Summary/Keyword: preparation condition

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Preparation and Oxygen Permeability of Tubular $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ Membranes with $La_{0.6}Sr_{0.4}Ti_{0.3}Fe_{0.7}O_{3-{\delta}}$ Porous Coating Layer (다공성의 $La_{0.6}Sr_{0.4}Ti_{0.3}Fe_{0.7}O_{3-{\delta}}$가 코팅된 $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ 관형 분리막의 제조 및 투과 특성)

  • Kim, Jong-Pyo;Pyo, Dae-Woong;Park, Jung-Hoon;Lee, Yong-Taek
    • Membrane Journal
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    • v.22 no.1
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    • pp.8-15
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    • 2012
  • Tubular $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ membranes with $La_{0.6}Sr_{0.4}Ti_{0.3}Fe_{0.7}O_{3-{\delta}}$ porous coating layer were prepared by extrusion and dip coating technique. XRD and SEM result showed the tubular membrane possessed the perovskite structure and porouscoating layer (thickness= about $2{\mu}m$) in surface. The oxygen permeation test was measured at condition of ambient air (feed side) and vacuum (permeate side) in the temperature range from 750 to $950^{\circ}C$. The oxygen permeation flux of $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ tubular membrane with $La_{0.6}Sr_{0.4}Ti_{0.3}Fe_{0.7}O_{3-{\delta}}$ porous coating layer reached maximum $3.2mL/min{\cdot}cm^2$ at $950^{\circ}C$ and was higher than non-coated $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ tubular membrane. Long-term stability test result indicated that the oxygen permeation flux was quite stable during the 11 day.

Preparation of Black Ginseng and its Antitumor Activity (흑삼의 제조 및 항암효과)

  • Lee, Jee-Hyun;Shen, Gui-Nan;Kim, Eui-Keom;Shin, Hyun-Joong;Myung, Chang-Seon;Oh, Han-Jin;Kim, Dong-Hee;Roh, Seong-Soo;Cho, Won;Seo, Young-Bae;Park, Yong-Jin;Kang, Cheol-Woo;Song, Gyu-Yong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.4
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    • pp.951-956
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    • 2006
  • The purpose of this study is to prepare black ginseng and evaluate its antitumor activity. In order to achieve such aim, 5 year fresh ginsenges were steamed at 95'E for 3 hr in pottery apparatus and dried at $60^{\circ}C$ for 12-36 hr. This process was repeated again nine times in same condition. Among the ginseng saponins in black ginseng, the amount of Ginsenoside $Rg_3$ was examined by HPLC. 10.05 mE of Ginsenoside $Rg_3$ was obtained from 1 g of dried black ginseng prepared. The extract of black ginseng exhibited stronger cytotoxic activity against MCF-1, HT-1080 and Hepa 1C1C7 tumor cell lines in vitro than the extract of red ginseng. Also, the extract of black ginseng exhibited stronger antitumor activity(33%) in BDFl mice bearing Lewis lung carcinoma cells(LLC) than the extract of red ginseng(23%). From these results, it was concluded that Black ginseng had antitumor activity suggesting its application for the prevention and treatment of cancer.

Preparation of PMSQ/TiO2 Composite Fine Powder by Sol-Gel Process (Sol-Gel Process를 이용한 PMSQ/TiO2 복합 미립자의 합성)

  • Lee, Dong Hyun;Koo, Sangman
    • Applied Chemistry for Engineering
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    • v.9 no.5
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    • pp.634-638
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    • 1998
  • Monodisperse, spherical $PMSQ/TiO_2$ composite fine powders were prepared by modified sol-gel process where 300 nm $TiO_2$ fine powders were used as seed particles for hetero-condensation with hydrolyzed MTMS (Methyltrimethoxysilane). The reaction was carried out under $N_2$ atmosphere at ambient temperature using $NH_3$ as a catalyst. Methanol was used as a solvent. Powder was obtained by the filtration of the solution with a glass filter and washing with acetone. The stirring rate, reaction temperature, $[H_2O]/[MTMS]$ and $[MTMS]/[TiO_2]$ ratio were varied to investigate shapes and sizes of particles. Monodisperse particles of $1-2{\mu}m$ diameter were obtained with [MTMS]=0.2 M, $[NH_3]=0.6M$, $[H_2O]/[MTMS]=100$, $[MTMS]/[TiO_2]=10-50$ at ambient temperature with mild stirring condition. These composite particles had a contact angle of almost 180 degree contact angle with water, which proves their excellent hydrophobicity. The study of UV absorption spectra showed that they have UV protecting effect.

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A Study on The Preparation of Poly(alkyl methacrylate-co-maleic anhydride) as Cold Flow Improvers for Biodiesel Fuels (바이오디젤용 저온 유동성 향상제로서의 폴리 (알킬메타크릴레이트-공-무수말레인산) 제조 연구)

  • Hong, Jin-Sook;Chung, Keun-Wo;Kim, Young-Wun;Kim, Nam-Kyun;Im, Dae-Jae
    • Applied Chemistry for Engineering
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    • v.23 no.2
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    • pp.232-240
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    • 2012
  • Bio-diesel (BD) is the mono alkyl esters of long chain fatty acids derived from renewable feed stocks like vegetable oils or animal fats. Bio-diesel shows poorer fuel properties than that of diesel fuel in a cold condition. For the diesel fuel, many cold flow improvers have been developed; however, since primary ingredients of bio-diesel are different from those of the diesel fuel, there is a limit to the cold flow improvement when the same cold flow improvers are added to bio diesel. In this study, to improve low temperature properties of bio-diesel, we developed a cold flow improver using an alkyl methacrylate monomer, prepared via ester reaction, and maleic anhydride and also conducted a ring opening reaction using amine. We characterized the products using $^1H-NMR$, FT-IR and GPC methods. In addition, the cold flow improvements of the products in Soybean BD and Palm BD in the concentration rage of 1000~10000 ppm were investigated. It was found that the addition of LMA2SMA6MA2-C8A in Soybean BD improved the pour point by $12.5\;^{\circ}C$.

Preparation of Honeycomb Carbon Dioxide Adsorbent Impregnated $K_2CO_3$ and Its Characterization ($K_2CO_3$를 담지시킨 고체 허니컴 이산화탄소 흡수제의 제조 및 이의 특성 평가)

  • Lee, Dong-Chul;Kim, Jin-Bae;You, Yoon-Jong
    • Applied Chemistry for Engineering
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    • v.23 no.6
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    • pp.624-629
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    • 2012
  • To capture and recover carbon dioxide ($CO_2$), we impregnated honeycomb made of ceramic paper with $K_2CO_3$ and its absorption characteristics of $CO_2$ were investigated. The absorption amount of $CO_2$ on the honeycomb absorbent impregnated with $K_2CO_3$ was 13.8 wt% at a constant temperature ($70^{\circ}C$) and relative humidity (66%) condition. Because the absorption amount of $CO_2$ achieved almost the same loading ratio of $K_2CO_3$ (17.6 wt%), the absorption reaction of $CO_2$ by $K_2CO_3$ on the honeycomb absorbent seems to be going smoothly. In addition, $CO_2$ absorption breakthrough characteristics of the honeycomb absorbent were analyzed at the temperature range of $50{\sim}80^{\circ}C$, and the water vapor was fed to an absorption column before the feeding of $CO_2$ or simultaneously with $CO_2$. As a result, the absorption capacity of $CO_2$ was more enhanced using the water vapor supplying before $CO_2$ than that of simultaneous supplying. It was confirmed by temperature programmed desorption analysis that the $KHCO_3$ produced by the absorption reaction of $K_2CO_3$ and $CO_2$ is regenerated by the desorption of $CO_2$ at a temperature of about $128^{\circ}C$.

Scientific Study for the Standardization of the Preparation Methods for Kyongdan(IV) -for the focus on the volume of water and volume of slat- (경단 조리법의 표준화를 위한 조리과학적 연구 (IV) -첨가하는 물의 양과 소금의 양을 중심으로-)

  • 한경선;김기숙
    • Korean journal of food and cookery science
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    • v.10 no.1
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    • pp.71-75
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    • 1994
  • This study attempted to examine the effect on sensory characteristics and texture of Kyongdan in various volume of adding water and volume of adding salt the most favorite tendency on the guality was at the 25% adding water and 1∼1.5% adding salt. Evaluation was conducted through sensory evaluation and objective evaluation The results were summarized as follows. 1. In sensory evaluation on various volume of water and volume adding salt the most favorite tendency on the gualtity was at the 25vo adding water and 1∼1.5% adding salt. 2. This condition corresponded to the low level of hardness, adhesiveness, gumminess, chewiness and high level of springiness in compa-rison with Instron measurement. In summary the most favorite factor is 12 hours soaking time, 25% adding water (hot water), 1∼1.5% adding salt, over 50 times kneading.

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Preparation and Physicochemical Characteristics of Anchovy Hydrolysates Produced by High Hydrostatic Pressure and Enzymatic Hydrolysis Treatment (고압/효소분해 처리에 의한 멸치 가수분해물의 제조 및 특성분석)

  • Kim, Min-Ji;NahmGung, Bae;Kim, Bok-Nam;Lee, Soo-Jeong;Kim, Chul-Jin;Cho, Yong-Jin;Kim, Chong-Tai
    • Food Engineering Progress
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    • v.13 no.2
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    • pp.85-91
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    • 2009
  • High hydrostatic pressure and enzymatic hydrolysis (HPEH) was applied to anchovy in order to produce a natural seasoning ingredient. Total soluble solid, amino nitrogen, total nitrogen and the degree of hydrolysis of anchovy hydrolysates were investigated depending on the process parameters such as temperature, pressure, enzyme concentration and enzyme type. The optimal condition for anchovy hydrolysis was confirmed as temperature 50$^{\circ}C$, reaction time 24 hrs, pressure 50 MPa and enzyme concentration 0.6% in HPEH treatment. HPEH treatment showed more effective in overall properties of anchovy hydrolysis than those of control. All anchovy hydrolysates produced by HPEH treatment were increased more 1.5-2.6 times of total free amino acid than that of control. From these results, the HPEH treatment appears to be an effective and economic process to produce a natural seasoning ingredients.

Efficient Synthesis of hypho-2,5-$S_2B_7H_{11}$ and Preparation of New nido-, arachno-, and hypho-Metalladithiaborane Clusters Derived from Its Anion hypho-$S_2B_7H_{10}{^-}$

  • 강창환;김성준;고재정;강상욱
    • Bulletin of the Korean Chemical Society
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    • v.16 no.11
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    • pp.1067-1074
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    • 1995
  • Reaction of arachno-S2B7H8- with either THF or 1,2-dimethoxyethane upon refluxing condition results in the formation of the previously known compound hypho-S2B7H10-. Protonation of hypho-S2B7H10- with HCl/Et2O generates hypho-2,5-S2B7H11 in good yield. This hypho-S2B7H10- anion has been employed to generate a series of new nido-, arachno-, and hypho-metalladithiaborane clusters. Reaction of the anion with Cp(CO)2FeCl results in direct metal insertion and the formation of a complex containing the general formula (η5-C5H5)FeS2B7H8. Spectroscopic studies of nido-6-CpFe-7,9-S2B7H8 Ⅰ demonstrated that compound Ⅰ was shown to have an nido-type cage geometry derived from an octadecahedron missing one vertex, with the iron atom occupying the three-coordinate 6-position in the cage and the two sulfurs occupying positions on the open face of the cage. Reaction of hypho-S2B7H10- with CoCl2/Li+[C5H5]- gave the previously known complex arachno-7-CpCo-6,8-S2B6H8 Ⅱ. Also, the reaction of the anion with [Cp*RhCl2]2 gave the complex arachno-7-Cp*Rh-6,8-S2B6H8 Ⅲ, the structure of which was shown to be that of complex Ⅱ. The similarity of the NMR spectra of Ⅱ and Ⅲ suggest that Ⅲ adopts cage structure similar to that previously confirmed for Ⅱ. A series of 9-vertex hypho clusters in which the sulfur atoms are bridged by different species isoelectronic with a BH3 unit, such as HMn(CO)4 or SiR2 have been prepared. Compounds Ⅳ,Ⅴ and Ⅵ are each 2n+4 skeletal electron systems and would be expected according to skeletal electron counting theory to adopt hypho-type polyhedral structures derived from an icosahedron missing three vertices. The complex hypho-1-(CO)4Mn-2,5-S2B6H9 Ⅳ was obtained by the reaction of the anion with (CO)5MnBr and has been shown from spectroscopic data to consist of a (CO)4Mn fragment bound to the two sulfur atoms S2 and S5 of hypho-S2B7H10-. Also, similar hypho-type complexes hypho-1-R2Si-2,5-S2B6H8 (R=CH3 Ⅴ, R=C6H5 Ⅵ) have been prepared from the reaction of hypho-S2B7H10- with R2SiHCl.

Studies on the tolerance of Halophyte Arabis stelleri under heavy metals and Salt stress condition (염생식물 섬갯장대(Arabis stelleri var. japonica)의 중금속 및 고염 농도 스트레스 상태에서 내성 연구)

  • Kim, Donggiun
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.4
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    • pp.373-378
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    • 2019
  • In the marine area, the salt concentration in the soil increases, and the inland heavy metal pollution increases the damage of plants. In the inland industrial development area, researches on the genetic resources of plants together with the heavy metal accumulation of Co, Ni, Zn, and so on are required. Both of these problems have caused scientists to work hard to find plants that are likely to cause stress in plant roots. In this study, seeds of Arabis stelleri var. japonica collected near the shore were used for germination. The growth and development and tolerance of both Arabis and Arabidopsis seeds were investigated under laboratory culture conditions. As a result, Arabis showed resistance about 3 times in 250 mM nickle and cobalt, and more than 4 times in 1 mM zinc when compared to Arabidopsis. The tolerance of Arabis to Na salts increased by 20% or more at 50 mM concentration and Arabis was resistant to heavy metals and salt concentration. The accumulation of Na ions in the body was measured as a preparation for studying the intracellular mechanism. As a result, it showed a further decrease in resistance to ground water roots. It is considered that the activity of the exporting gene is important rather than the mechanism of accumulation.

Effects of Korean Red Ginseng extract on tissue plasminogen activator and plasminogen activator inhibitor-1 expression in cultured rat primary astrocytes

  • Ko, Hyun Myung;Joo, So Hyun;Kim, Pitna;Park, Jin Hee;Kim, Hee Jin;Bahn, Geon Ho;Kim, Hahn Young;Lee, Jongmin;Han, Seol-Heui;Shin, Chan Young;Park, Seung Hwa
    • Journal of Ginseng Research
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    • v.37 no.4
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    • pp.401-412
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    • 2013
  • Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to $319.3{\pm}65.9%$ as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 ${\mu}M$ each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI-1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.