• 제목/요약/키워드: Metal phosphate

검색결과 261건 처리시간 0.026초

Synthesis and Optical Properties of Poly(hydroxyphenylbenzoxazole): A Colorimetric and Fluorescent Sensor for Ionic Species

  • Lee, Jin-Koo;Kim, Tae-Hyun;Kim, Young-shin;Gang Li;Park, Won-Ho;Lee, Taek-Seung
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
    • /
    • pp.23-24
    • /
    • 2003
  • We synthesized a poly[2-(2'-hydroxyphenyl) benzoxazole] under the two step procedures of Suzuki coupling polymerization with corresponding monomers followed by the deprotection of benzyl group. The polymer in DMF solution is applicable to colorimetric sensing fluoride anion, which shows a color change from colorless to yellow. High sensitivity to fluoride anion compared to other anions such as phosphate, chloride, and sulfate is ascribed to the high coordination ability of the 2-(2'-hydroxy phenyl)benzoxazole moiety in the polymer chain. Emission shift by metal cations, which can be applied to fluorescent sensing w as also observed in the polymer solution.

  • PDF

삼인산 나트륨과 아질산 나트륨에 의한 탄소강 부식방지 특성 연구 (Study on The Corrosion Inhibition Characteristics of Carbon Steel by Sodium Phosphate And Sodium Nitrite)

  • 문전수;이재근
    • Corrosion Science and Technology
    • /
    • 제9권3호
    • /
    • pp.137-141
    • /
    • 2010
  • Sodium nitrite is widely used as one of the popular corrosion inhibitors for the protection of ferrous metal in closed cooling water system, such as a diesel engine and a chiller. The optimum treatment conditions are studied through laboratory tests using linear polarization resistance (LPR) technique. Corrosion rate of the carbon steel electrode could be maintained less than $2.5{\times}10^{-3}$ mmpy in the test condition of 500 ppm as ${NO_2}^-$, 200 ppm as $Cl^-$, $70^{\circ}C$ and pH 6.8. The pH control is confirmed not to be an important factor in the protection of carbon steel by sodium nitrite inhibitor. The addition of tolyltriazole was needed for the protection of the copper alloy in the sodium nitrite treatment system.

Tannic acid를 이용한 전자현미경 (TEM) 염색효과 (Electron Microscopic Stain Effect by Tannic acid)

  • 윤철종;한정연;김철우;지제근
    • Applied Microscopy
    • /
    • 제24권2호
    • /
    • pp.37-47
    • /
    • 1994
  • Using mouse tissue, we studied electron opacity effect of tannic acid for transmission electron microscopic staining. Tannic acid-glutaraldehyde in 0.1M phosphate buffer was used as a fixative. To compare with this we have tested another method consisting of heavy metal staining after treatment of tannic acid in sodium tetraborate (borax) on glutaraldehyde-fixed sections. We have achieved equally consistent electron opacity in both methods. The elastin, collagen, basal lamina of skin and gap junctions of the epithelial cells gave excellent results, while it was good for glycogen, cilia, and plasma. Also fat cells and lipid droplets gave good preservation when tannic acid was added in the fixative. However, prolonged fixation in tannic acid-added fixative was hazardous for further processing, i.e., sectioning problem and deep electron opacity background.

  • PDF

PHILOS plate fixation with polymethyl methacrylate cement augmentation of an osteoporotic proximal humerus fracture

  • Kim, Do-Young;Kim, Tae-Yeong;Hwang, Jung-Taek
    • Clinics in Shoulder and Elbow
    • /
    • 제23권3호
    • /
    • pp.156-158
    • /
    • 2020
  • PHILOS plate fixation in osteoporotic proximal humerus fracture of old age is well-known for high complication rate, especially metal failure, providing various augmentation techniques, such as calcium phosphate cement, allogenous or autologous bone graft. We report a case of polymethyl methacrylate augmentation to provide appropriate reduction with a significant mechanical support. This can be a treatment option for displaced unstable osteoporotic proximal humerus fracture with marked bony defect.

VENT가 도재전장 주조관용 비귀금속 합금의 주조성에 미치는 영향에 관한 연구 (THE EFFECT OF THE VENT ON THE CASTABILITY OF A NONPRECIOUS ALLOY USED FOR PORCELAIN-FUSED-TO-METAL CROWN)

  • 이진걸;장완식
    • 대한치과보철학회지
    • /
    • 제23권1호
    • /
    • pp.145-154
    • /
    • 1985
  • To study the effect of the vent and dense surface of the phophate-bonded investment on the castability of a non-precious alloy used in PFM restoration, one-ended polypropylene straw patterns of 0.15mm thick, 5mm radius. 10mm-high were cast with Vera Bond. The following results were obtained. 1. Thin patterns could be cast completely with a non-precious alloy. 2. No difference in the castability was found among the patterns with vent, chill vent and with out vent. 3. Dense surface of the phosphate-bonded investment had no effect on the cast ability of a nonprecious alloy.

  • PDF

Target-Composition Effect on Hydroxyapatite Thin Films Coated on Titanium by r.f. Sputtering

  • Hamagami, Jun-ichi;Kokubu, Daisuke;Umegaki, Takao;Yamashita, Kimihiro
    • The Korean Journal of Ceramics
    • /
    • 제4권4호
    • /
    • pp.372-376
    • /
    • 1998
  • Using calcium-phosphate-powder targets with the Ca/P ratios of 1.0-1.67, hydroxyapatite ($Ca_{10}(PO_4)_6(OH)_2$, HAp) thin films with 4-7㎛ thickness were prepared on titanium metal plates by r.f. magnetron sputtering, followed an annealing at $200^{\circ}C$ for 24 hr under a high water vapor pressure using an autoclave. All the specimens were systematically characterized by XRD, FT-IR, SEM and EDS analyses. The post-annealed films were confirmed to be a nonstoichiometric oxyhydroxyapatite by XRD and FT-IR measurements.

  • PDF

리륨이차전지용 $LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ 양극활물질의 표면개질에 따른 전지특성 (Cell Performances of Surface-Treated $LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ Material for Li Secondary Battery)

  • 김현수;공명철;김기택;문성인
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
    • /
    • pp.294-295
    • /
    • 2007
  • $LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ material was surface modified with Zr-phosphate. Scanning electron microscope, energy dispersive spectroscopy and electrochemical studies indicate that surface modification improve the rate capability. Electrochemical studies were performed by assembling 2032 coin cells with lithium metal as an anode.

  • PDF

고온 인산염 유기 전해질에서의 TiO2 나노구조 형성 원리와 응용 (A Review of Anodic TiO2 Nanostructure Formation in High-temperature Phosphate-based Organic Electrolytes: Properties and Applications)

  • 오현철;이영세;이기영
    • 공업화학
    • /
    • 제28권4호
    • /
    • pp.375-382
    • /
    • 2017
  • 전기화학 방법을 이용한 이산화티타늄 나노구조에 대한 기존 연구는 불소 이온을 함유한 전해질에서의 산화반응으로 형성된 나노튜브가 연구의 주를 이루고 있다. 최근, 불소 이온이 아닌 고온 인산염이 함유된 글리세롤계 전해질의 개발로 관련 연구가 활발히 진행되고 있다. 본 총설은 이러한 전해질을 활용하여 다양한 이산화티타늄 나노구조를 형성하는 연구 동향에 대해 다루고 있다. 새로운 양극산화법을 통해 형성된 이산화티타늄 나노구조는 기존의 나노튜브에 비하여 비표면적이 넓고 결정성과 접착력이 우수하여 여러 응용분야에 활용가치가 높다. 이에 본 총설에서는 새로운 양극산화법을 이용한 나노구조의 형성 원리, 특성에 대한 개괄적 접근 뿐만 아니라 실제 응용분야에서의 소재성능을 기존 나노튜브 구조와 비교한 결과 등을 망라하여 자세히 소개하고 있다.

샴푸와 의류용 분말세제의 생분해도와 인산염 및 중금속 함량에 대한 연구 (The Study on the Biodegradability and Phosphate, Heavy Metal Contents of Shampoos and Powder Detergents for Clothing)

  • 고영신;김세경;임종완;유찬주;최성용
    • 분석과학
    • /
    • 제11권2호
    • /
    • pp.105-111
    • /
    • 1998
  • 현재 국내에서 시판 중인 샴푸와 의류용 분말세제 중 대표적인 제품(샴푸6종, 의류용 분말세제 6종)을 대상으로 계면활성제의 생분해도를 측정하고, 부영양화의 원인이 되는 인산염의 함유 여부와 인체에도 직접적인 영향을 미치는 중금속(Pb, Cd, As 및 Hg)을 분석하였다. 분석결과 샴푸와 의류용 분말세제 시료 전제품이 KS규격에 모두 적합하였다. 그러나 sodium ${\alpha}$-olefin sulfonate(AOS), linear alkylbenzene sulfonate(LAS) 및 합성 sodium lauryl etoxylate sulfonate(SLES) 성분이 상대적으로 다량 포함되어 있는 제품의 생분해도가 느리다는 것을 알 수 있었으며, 이들 계면활성제가 석유계라는 사실로부터 천연 추출 계면활성제보다 생분해도가 낮다는 것을 알 수 있었다. 인산염과 중금속 함유량은 모두 화장품기준에 적합한 우수한 제품인 것을 확인할 수 있었다.

  • PDF