• 제목/요약/키워드: Surface chemistry

검색결과 3,795건 처리시간 0.045초

Raman Spectroscopy of L-Phenylalanine, L-Tyrosine, and their Peptides Adsorbed on Silver Surface

  • Lee, Hong-In;Kim, Myung-Soo;Suh, Se-Won
    • Bulletin of the Korean Chemical Society
    • /
    • 제9권4호
    • /
    • pp.218-223
    • /
    • 1988
  • The surface-enhanced Raman scattering of L-phenylalanyl-glycine (L-Phe-Gly), L-phenylalanyl-glycyl-glycine (L-Phe-Gly-Gly), glycyl-glycyl-L-phenylalanine (Gly-Gly-L-Phe), L-tyrosyl-glycine (L-Tyr-Gly), and L-tyrosyl-glycyl-glycine (L-Tyr-Gly-Gly) adsorbed on silver colloidal particles have been investigated. More detailed investigations on the surface-enhanced Raman scattering from L-phenylalanine (L-Phe), glycyl-L-phenylalanine (Gly-L-Phe), L-tyrosine (L-Tyr), and glycyl-L-tyrosine (Gly-L-Tyr) than in ref. 17 have also been made. It has been found that the above molecules adsorb on the surface via both the carboxylate ($COO^-$) and amino ($NH_2$) groups.

A Theoretical and Experimental Study of Physical Adsorption of Gases on Uniform Flat Solid Surface

  • Lee, Jo-Woong;Chang, Sei-Hun;Yoon, Jae-Shin
    • Bulletin of the Korean Chemical Society
    • /
    • 제10권3호
    • /
    • pp.292-297
    • /
    • 1989
  • In this work we have experimentally observed the physisorption isotherms for nitrogen, TMS, cyclohexane, benzene, and n-hexane adsorbed on flat aluminum foil surface and have analyzed them theoretically on the basis of the theory proposed by Chang et al. The results show that the theory by Chang et al. can provide a useful means to describe the physisorption of gases on uniform flat solid surface which is essentially important for analysis of the pore volume distribution in porous solid surface. We have also discussed the application of the results obtained in this work to the analysis of pore volume distribution in porous alumina we reported previously.

XPS Studies of Oxygen Adsorption on Polycrystalline Nickel Surface

  • Lee, Soon-Bo;Boo, Jin-Hyo;Ahn, Woon-Sun
    • Bulletin of the Korean Chemical Society
    • /
    • 제8권5호
    • /
    • pp.358-362
    • /
    • 1987
  • The interaction of oxygen with polycrystalline nickel surface has been studied by investigating the X-ray photoelectron spectra of O 1s, Ni $2p_{3/2}$, and their valence band electrons. By comparing the oxygen exposure of this work with the reported results of LEED, AES, and work function measurements, it is found that the atomic oxygen, adsorbed dissociatively in the initial stage of exposure, is responsible for a p(2 ${\times}$ 2) structure and a subsequent c(2 ${\times}$ 2) structure on the Ni(100) surface. This dissociatively adsorbed oxygen species forms surface NiO layer subsequently on further oxygen exposure. The NiO layer is more easily formed with the increasing temperature. Non-stoichiometric oxygen species is also found to accompany the NiO layer. It appears prior to the formation of bulk NiO at all of the temperatures of this work except at 523K.

A Study of the Diastereoselectivity of Diels-Alder Reactions on the Ce-SiO2 as Support

  • Ziarani, Ghodsi Mohammadi;Badiei, Alireza;Miralami, Azam
    • Bulletin of the Korean Chemical Society
    • /
    • 제29권1호
    • /
    • pp.47-50
    • /
    • 2008
  • The diastereoselectivity of Diels-Alder reactions were studied on the silica surface supported with different concentrations of cerium ion as efficient Lewis acid catalysts under solvent-free conditions. The results showed that the diastereoselectivity of reaction was highly improved in these conditions. The cerium ion was grafted on silica surface by using ion exchange method.

Surface-enhanced Raman Scattering on Chemically Prepared Silver Film for Trace Analysis

  • Boo, Doo-Wan;Kim, Kwan;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
    • /
    • 제7권1호
    • /
    • pp.55-58
    • /
    • 1986
  • Analytical capability of surface-enhanced Raman scattering has been evaluated. Silver films prepared by homogeneous chemical reduction were used as the substrate. Detection limits for p-nitrobenzoic acid, thiophenol and rhodamine 6G were around $10{\sim}100\;pg$.