• Title/Summary/Keyword: silica-gel

Search Result 1,513, Processing Time 0.027 seconds

Characterization of Titania plate and Nano Titania Coated Beads for Photoelectrocatalytic system(PECS) (광전자촉매 시스템(PECS)에 사용할 광촉매 금속판과 비드의 특성고찰)

  • Do, Young-Woong;Ha, Jin-Wook
    • Proceedings of the KAIS Fall Conference
    • /
    • 2008.11a
    • /
    • pp.354-357
    • /
    • 2008
  • 본 연구는 광전자촉매 시스템(PECS) 적용을 위하여 광촉매 금속판과 코팅비드를 제조하여 특성을 고찰하였다. 광촉매 물질의 회수가 용이하고, 실용화하기 위하여 티타늄 금속판을 $400^{\circ}C$에서 $700^{\circ}C$까지 $50^{\circ}C$에서 $100^{\circ}C$간격으로 토치를 사용하여 산화처리 하였으며, 비드의 경우 alumina, glass, silica gel beads에 TTIP([Ti$(OC_3H_7)_4$], Aldrich)을 전구체로 사용하여, 유동층 화학기상증착공정(Fluidized Bed Chemical Vapor Deposition, FB-CVD)으로 박막코팅을 하였다. 광촉매 금속판의 경우 산화처리 후 외관상태와 성분분석 시 최적조건은 $400^{\circ}C{\sim}500^{\circ}C$ 60분간 토치로 산화하였을 때였으며, 광촉매 코팅비드의 경우 silica gel beads가 본연의 다공구조를 나타내며 박막코팅이 되어, 상대적으로 alumina, glass beads에 비해 반응표면적이 크게 나타났다.

  • PDF

Isolation and Characterization of 4-hydroxycinnamic Acid with Antimicrobial Activity from Aralia eiata (두릅에서 항미생물활성을 갖는 4-hydroxycinnamic acid의 분리 및 동정)

  • Ma, Seung-Jin;Kuk, Ju-Hee;Ko, Byoung-Seob;Park, Keun-Hyung
    • Applied Biological Chemistry
    • /
    • v.39 no.4
    • /
    • pp.265-267
    • /
    • 1996
  • The methanol extracts of AraIia elata showed antimicrobial activity against bacteria. The antimicrobial active principle was successively purified with solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, silica gel partition column chromatography and HPLC. The active substance was isolated by HPLC on $C_{18}$ column with an acetic acid-MeOH system. The active substance was identified as trans-4-hydroxycinnamic acid by MS, $^1H-NMR\;and\;^{13}C-NMR$.

  • PDF

Purification of Antimicrobial Substance for the Extract from the Root Bark of Morus alba (상백피 추출물로부터 향균성 물질의 분리정제)

  • 박욱연;김신희;김지회;김용관;장동석
    • Journal of Food Hygiene and Safety
    • /
    • v.10 no.4
    • /
    • pp.225.1-230
    • /
    • 1995
  • The ethanol extract from the root bark of Morus alba showed the strongest antimicrobial activity on the growth of almost all the tested microorganisms which were food-borne pathogens and food-related microorganisms. 1) In order to isolate and purify of antimicrobial substance extracted from the root bark of Morus alba, the antimicrobial substance from the ethanol extract which exhibited a strong antimicrobial activity was purified by solvent fractionation, silica gel column chromatography, TLC and HPLC. Among the fractions fractionated by 4 kind of solvents from the ethanol extract, the antimicrobial activity of ethyl acetate fraction had the strongest antimicrobial activity against B. subtilis. Unknown compound were isolated from the ethyl acetate fraction by silica gel column chromatography, TLC and HPLC and the compounds showed strong absorbance at 207, 217 and 285 nm, therefore, it was supposed to be a kinds of aromatic compound.

  • PDF

Effects of Packaging on Storage Stability and Chlorophyll Contents of Dried, Roasted and Roasted-Seasoned Laver during Storage (포장지에 따른 건조, 구이, 조미김의 저장 안전성과 Chlorophyll 함량에 관한 연구)

  • 이숙경
    • Journal of Food Hygiene and Safety
    • /
    • v.14 no.2
    • /
    • pp.134-139
    • /
    • 1999
  • The relationship between storage stability and chlorophyll contents of dried laver(DL), roasted laver(RL) and roasted seasoned laver(RSL) according to packaging during storage at 20$\pm$0.5$^{\circ}C$ were investigated by measuring the acid value(AV) and the peroxide value(POV). There results are as follows; 1.The storage stability was decreased in the rank of 0 < 3< 6 < 9 months by storage term, RL < DL < RSL by the kind of laver products and PP/PE/AL/PE/LLDPE(Al) < PP/PE(PP) y packaging. 2. When the silica gel was added to RSL, the storage stability was improved. The more the addition level of silica gel was increased, the more the storage stability was improved. The rank order was 2g < 4g in RSL. 3. Reduction of the total chlorophyll content in RSL were deacreased to 10% when packed with Al and 24% when packed with PP.

  • PDF

Thermal conductivity properties of cement matrix utilizing diatomite and silica gel (규조토 및 실리카겔을 혼입한 시멘트 경화체의 열전도율 특성)

  • Kim, Ki-Hoon;Pyeon, Su-Jeong;Lee, Sang-Soo;Song, Ha-Young
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2018.05a
    • /
    • pp.230-231
    • /
    • 2018
  • Recently, the danger for radioactive materials has become a hot topic. Beginning with the Chernobyl nuclear accident in 1996, in 2011, the Fukushima nuclear power plant in Japan suffered major damage such as large-scale casualties and radioactive dangerous area selection. Concerns about leakage of radioactive materials due to recent earthquakes have been deepening in Korea, such as Wolsong Nuclear Power Plant in Gyeongju, and there is a growing interest in the safety of radioactive materials through the media and the media. However, the route to exposure to radioactive materials is not limited to these large-scale nuclear accidents. Typical examples of this are radioactive substances exposed in daily life. In the case of radon gas, the danger is being revealed through current events programs and news, and natural radiation exposure is attracting attention.

  • PDF

2D Nanodot and Nanowires Arrays of Titania and Silica with Tunable Morphologies via Self-Assembled Block Copolymers and Sol-gel Chemistry (자기조립 이중블록공중합체와 졸-겔 공정을 이용한 이산화티타늄과 이산화규소 2차원 나노점 및 나노선 배열의 모폴로지 제어)

Investigation of Brassinosteroid Substances in Undmia pinnatifida (미역의 Brassinosteroid 활성물질검색)

  • 문제학;현규환박근형
    • KSBB Journal
    • /
    • v.7 no.1
    • /
    • pp.21-26
    • /
    • 1992
  • In order to examine the presence of brassinosteroid substance in sea mustard(Undaria pinnatifida), leaves of sea mustard were extracted with MeOH. The extract was purified by slovent fractionation, counter current distribution, silica gel adsorption chromatography, charcoal adsorption chromatography, Bondesil chromatography, and reverse phase HPLC, successively. The activity was monitored by the rice inclination test and its prescence could be confirmed in each purification step. Although sea mustard contained a less amount of the active substance than the vegetative tissue of higher plants, brassinosteroid was clearly present endogenously in sea mustard. We acknowledge that our work is probably the first publication reporting the presence of brassinosteroid in marine algae plants.

  • PDF

A Study on the Ichthyotoxic Constituents of Chopi(Zanthoxylum piperitum DC) (한국산 초피의 어독성분에 관한 연구)

  • 김용두;강성구;오명록
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.22 no.5
    • /
    • pp.617-620
    • /
    • 1993
  • To Study an ichthyotoxicity of Zanthoxylum piperitum DC (Chopi) against fish(Misgurnus anguillicaudatus), the bark of Chopi was extracted with water, methanol and chloroform. The ichthyotoxicities of each extract were found in order of MeOH extract, $H_2O$ extract, dried-powder of Chopi and $CHCI_3$ extract. The active compound was isolated from the MeOH extract by silica gel column chromatography, HPLC and recrystalization, successively, and it was identified to be L-asarinin by the comparison of UV, GC-Mass and LC-Mass data.

  • PDF

Identification of Mushroom Brown Blotch Causing Agent from Pseudomonas tolaasii Culture Broth (Pseudomonas tolaasii 배양액으로부터 독성물질의 동정)

  • Park, Chul-Jin;Oh, Sung-Ki;Chun, Uck-Han
    • Applied Biological Chemistry
    • /
    • v.37 no.5
    • /
    • pp.392-396
    • /
    • 1994
  • The toxic substance causing blown blotching on the mushroom cap was extracted and purified from the culture broth of P.tolaasii. Purification and identification of the toxic compound was carried out with the silica gel chromatography, mass spectrum and NMR and appeared to be an aminobenzene in amylamine group. The purified toxic substance showed UV spectrum at 234nm and melting point at $76^{\circ}C$, respectively.

  • PDF

Isolation of S-627(A) and (B) as Candidates of Anticandiosis Agent (생리활성물질 S-627(A)와 S-627(B)의 분리)

  • Lee, Sang-Han;Lee, Dong-Sun;Seu, Young-Bae;Kim, Jong-Guk;Hong, Soon-Duck
    • Journal of Life Science
    • /
    • v.7 no.3
    • /
    • pp.186-191
    • /
    • 1997
  • In order to select new anticandiosis agent-producing candidates, we used a modified selection method. Two active fractions designated as S-6279A) and (B) were isolated from the fermentation broth of Streptomycetes sp. S627 which was screened by methanol extraction, diaion HP-20 and silica gel column chromatography (chloroform-me-thanol, and benzene-ethyl acetate), and preparative thin layer chromatography.

  • PDF