• 제목/요약/키워드: acid deposition

검색결과 558건 처리시간 0.022초

템플릿 없이 전해 합성된 코발트 나노 로드 (Electrolytic Synthesis of Cobalt Nanorods without Using a Supporting Template)

  • 김성준;신헌철
    • 한국재료학회지
    • /
    • 제24권6호
    • /
    • pp.319-325
    • /
    • 2014
  • Cobalt nano-rods were fabricated using a template-free electrochemical-deposition process. The structure of cobalt electro-deposits strongly depends on the electrolyte composition and on the density of the applied current. In particular, as the content of boric acid increased in the electrolyte, deposits of semi-spherical nuclei formed, and then grew into one-dimensional nano-rods. From analysis of the electro-deposits created under the conditions of continuous and pulsed current, it is suggested that the distribution of the active species around the electrode/electrolyte interface, and their transport, might be an important factor affecting the shape of the deposits. When transport of the active species was suppressed by lowering the deposition temperature, more of the well-defined nano-rod structures were obtained. The optimal conditions for the preparation of well-defined nano-rods were determined by observing the morphologies resulting from different deposition conditions. The maximum height of the cobalt nano-rods created in this work was $1{\mu}m$ and it had a diameter of 200 nm. Structural analysis proved that the nano-rods have preferred orientations of (111).

Effects of Muscle and Finishing Diets Containing Distillers Grains with Low Moisture Levels on Fatty Acid Deposition in Two Novel Value-added Beef Cuts

  • Giotto, Francine M.;Fruet, Ana Paula B.;Nornberg, Jose L.;Calkins, Chris R.;de Mello, Amilton S.
    • 한국축산식품학회지
    • /
    • 제40권3호
    • /
    • pp.484-494
    • /
    • 2020
  • This study evaluated the effects of muscle and dietary treatments including CORN, dry distillers grains (DDGS), and modified distillers grains (MDGS) on fatty acid (FA) deposition in two novel value-added beef cuts (Petite Tender - M. teres major - TM, and Flat Iron - M. infraspinatus - INF). Crossbred steers were randomly assigned to one of three dietary treatments (CORN, 40% of DDGS with 8%-12% of moisture, and 40% of MDGS with 45%-55% of moisture - DM basis) and fed for 190 days. The TM muscle had higher concentrations of ω6 FAs and polyunsaturated fatty acids (PUFA) when compared to INF. Beef fed CORN showed greater C16:0 and lower C18:0 values when compared to beef fed distillers grains (DGS). Beef fed DDGS had higher concentrations of ω6 FAs when compared to MDGS. Different moisture levels only affected FAs containing 14, 16, and 17 carbons. Different muscles, diets, and moisture levels of DGS affected the deposition of FAs in the lean.

Curcumin-Loaded PLGA Nanoparticles Coating onto Metal Stent by Electrophoretic Deposition Techniques

  • Nam, So-Hee;Nam, Hye-Yeong;Joo, Jae-Ryang;Baek, In-Su;Park, Jong-Sang
    • Bulletin of the Korean Chemical Society
    • /
    • 제28권3호
    • /
    • pp.397-402
    • /
    • 2007
  • Restenosis after percutaneous coronary intervention (PCI) continues to be a serious problem in clinical cardiology. To solve this problem, drug eluting stents (DES) with antiproliferative agents have been developed. Variable local drug delivery systems in the context of stenting require the development of stent manufacture, drug pharmacology and coating technology. We have worked on a system that integrates electrophoretic deposition (EPD) technology with the polymeric nanoparticles in DES for local drug delivery and a controlled release system. The surface morphology and drug loading amount of DES by EPD have been investigated under different operational conditions, such as operation time, voltage and the composition of media. We prepared poly-D,L-lactide-co-glycolic acid (PLGA) nanoparticles embedded with curcumin, which was done by a modified spontaneous emulsification method and used polyacrylic acid (PAA) as a surfactant because its carboxylic group contribute negative charge to the surface of CPNPs (?53.5 ± 5.8 mV). In the process of ‘trial and error' endeavors, we found that it is easy to control the drug loading amount deposited onto the stent while keeping uniform surface morphology. Accordingly, stent coating by EPD has a wide application to the modification of DES using various kinds of nanoparticles and drugs.

New insights about coke deposition in methanol-to-DME reaction over MOR-, MFI- and FER-type zeolites

  • Migliori, Massimo;Catizzone, Enrico;Aloise, Alfredo;Bonura, Giuseppe;Gomez-Hortiguela, Luis;Frusteri, Leone;Cannilla, Catia;Frusteri, Francesco;Giordano, Girolamo
    • Journal of Industrial and Engineering Chemistry
    • /
    • 제68권
    • /
    • pp.196-208
    • /
    • 2018
  • The effect of channel-system of zeolite on methanol-to-DME reaction was studied. Results revealed that channels size and topology affect catalyst lifetime, type and location of coke precursors. FER and MFI showed the best resistance towards coke deposition, whilst fast deactivation was observed on MOR. Although the higher concentration and strength of acid sites, FER structure formed a lower coke amount, preferably located within the pores, while coke cluster deposited on the external surface of MOR. Analysis of acid sites distribution and strength was performed during deactivation-regeneration process. Coke location assessment was also supported by molecular simulations.

Arachidic acid와 Stearic acid의 누적전이와 전기특성 (Deposition Transfer and Electrical Properties of Arachidic acid and Stearic acid)

  • 최영일;송진원;이경섭
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
    • /
    • pp.764-767
    • /
    • 2001
  • Because using LB method, result that produce Arachidic acid and Stearic acid LB film and measure the accumulation characteristic and electrical characteristic is as following. Organic monolayers of surface of the water compression each 9 layer's LB film to slide glass and manufactured MIM device compressing molecular film only. Could confirm that accumulation was good seeing as absorption coefficient and SEM picture, AFM picture that prevent manufactured LB films. Formation of domain of coexistence form that prevent LB film is indefinite and distinction of border side was not clear, and could know that roughness appears greatly. Obtained current by applied voltage could know that is proportional almost, though Arachidic acid appeared as bulk of current that happen in equaler certification voltage than Stearic acid is less, this alkyl chain longer Arachidic acid that serving relations special quality is superior know can .

  • PDF

RELATIVE EFFICIENCIES OF YELLOW CAROTENOIDS FOR EGG YOLK PIGMENTATION

  • Balnave, D.;Bird, J.N.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제9권5호
    • /
    • pp.515-517
    • /
    • 1996
  • The relative efficiencies of deposition into egg yolk of apo-carotenoic acid ester(APO-E, CAROPHYLL Yellow) and saponified marigold xanthophylls (MX), in the presence of canthaxanthin (CN), were determined using a wheat-based diet. APO-E was deposited with an efficiency of 50 percent and MX with an efficiency between 13 and 20 percent. The dose response relationship for MX was curvilinear with a decreased efficiency at higher concentrations. Canthaxanthin was deposited with and efficiency of 38 percent, irrespective of the source of yellow xanthophylls, up to a dietary concentration of 5.5 mg/kg. At a dietary MX concentration of 8.3 mg/kg the efficiency of deposition of CN declined to 24 percent. The results confirm that the replacement ratio of MX : APO-E is between 3 : 1 and 4 : 1 depending on the dietary inclusion of marigold pigment.

Carbonate Crystal Growth Controlled by Interfacial Interations of Artifical Cell Membranes

  • Goh, Dai-Young;Ahn, Dong-June
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • 제2권2호
    • /
    • pp.109-112
    • /
    • 1997
  • Morphology of carbonate crystals grown on the surface of artificial cell membranes was controlled by changing the interfacial chemistry. For octadecyltriethoxysilane (OTE) films with terminal methyl groups interacting little with an aqueous calcium carbonate solution calcite (104) crystals were formed. Polymerized pentacosadiynoic acid (PDA) films with terminal carboxylic acid groups induced deposition of calcite (012) crystals aligned along with each other within a polymer domain. On the other hand, stearyl alcohol (StOH) films with terminal hydroxyl groups induced deposition of aragonite crystals. When PDA was mixed with StOH, the 8:1 PDA:StOH (molar ratio) film produced dominating calcite (012) crystals without any crystal alignment, and the 4:1 mixture film produced minor calcite (012) crystals and major aragonite crystals. For the 2:1, 1:1, 1:2, and 1:4 mixture films, aragonite crystals were dominating. Hence, it is found that the chemical composition at the interface plays a very important role in controlling the morphology of deposited carbonate crystals.

  • PDF

플렉시블 OLED 패시베이션용 유기 박막 제작 및 특성 (Fabrication of Organic Thin Film for Flexible OLED Passivation and Its Characterization)

  • 김관도
    • 반도체디스플레이기술학회지
    • /
    • 제19권1호
    • /
    • pp.93-96
    • /
    • 2020
  • Polyimide thin film was prepared by annealing the polyamic acid that was synthesized through co-deposition of diamine and dianhydride. The polyamic acid and polyimide thin film were characterized with FT-IR and HR FE-SEM. The average roughness of the film surface, evaluated with AFM, were 0.385 nm and 0.299 nm after co-deposition, and annealing at 120 ℃ respectively. OLED was passivated with the polyimide layer of 200 nm thickness. While the inorganic passivation layer enhances the WVTR of OLED, the organic passivation layer gives flexibility to the OLED. The in-situ passivation of OLED with organic thin film layer provides the leading technique to develop flexible OLED Display.

진공도가 텅스텐 산화물 방막의 전기적 착색특성에 미치는 영향 (Influence of vacuum Pressure on Electrochnnc Properties of $WO_3$ Films)

  • 이길동
    • 태양에너지
    • /
    • 제17권4호
    • /
    • pp.67-74
    • /
    • 1997
  • The electrochromic $WO_3$ thin films were prepared by using the electron beam deposition technique. The influences of vacuum pressure were examined in terms of the surface morphology and the electrochromic properties of films. From the results, the electrochromic behavior of electron beam deposited films strongly depends on the vacuum pressure during deposition. The film prepared under a vacuum pressure of $5{\times}10^4$ mbar was found to be rather stable when subjected to the repeated coloring and bleaching cycles in an aqueous acid electrolyte of 1M $H_2SO_4$. It was also found that the degraded film by repeated cycling in the aqueous acid solution changed the grain shape of film surface.

  • PDF

열증착 시료 제작법이 적용된 MALDI 질량분석법에 의한 불용성 Sorbitol 유도체의 분자량 결정 (Application of Thermal Vapor Deposition Method for MALDI-MS : Molecular Weight Determination of Insoluble Sorbitol Derivatives)

  • 신철민;남해선;김성호
    • 한국산학기술학회논문지
    • /
    • 제4권3호
    • /
    • pp.260-262
    • /
    • 2003
  • A thermal vapor deposition method for crystallization of insoluble analytes with matrix is established as a new sample preparation method for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). A mixture of mono, bis and tris(p-ethyl benzylidene) sorbitols was incorporated into microcrystals of ferulic acid, which was confirmed by confocal micrographs. Molecular masses of sorbitol derivatives were determined in this way by MALDI-MS without thermal decomposition.

  • PDF