We have measured the X-ray reflectivity of rubbed polyimide films used for liquid crystal alignment. Both mechanically rubbed polyimides and polyimides ?rubbed? by linearly polarized UV light were examined. The mechanism for liquid crystal alignment in the optically rubbed films is still unclear; suggested mechanisms include either the formation of large-scale ?ripples? due to anisotropic contraction which in turn interact with the liquid crystal, or reorientation of individual polymer molecules. The mechanical rubbing process creates microgrooves on the surface of the polyimide film, which on average run parallel to the rubbing direction. These grooves result in anisotropic off-specular X-ray reflectivity features. The analysis of the specular reflectivities obtained from these films will produce a comparison of the roughness associated with both mechanically and optically rubbed films, parallel and perpendicular to the rubbing direction. We use specular reflectivity, together with the anisotropic character of our resolution function to extract the anisotropy in the roughness along the film surface. ITEM

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR001633-20
Application #
6618433
Study Section
Project Start
2002-09-01
Project End
2003-08-31
Budget Start
Budget End
Support Year
20
Fiscal Year
2002
Total Cost
Indirect Cost
Name
Albert Einstein College of Medicine
Department
Type
DUNS #
009095365
City
Bronx
State
NY
Country
United States
Zip Code
10461
Vongsvivut, Jitraporn; Fernandez, Jason; Ekgasit, Sanong et al. (2004) Characterization of supported cylinder-planar germanium waveguide sensors with synchrotron infrared radiation. Appl Spectrosc 58:143-51
Masip, Lluis; Pan, Jonathan L; Haldar, Suranjana et al. (2004) An engineered pathway for the formation of protein disulfide bonds. Science 303:1185-9
Huang, Raymond Y; Miller, Lisa M; Carlson, Cathy S et al. (2003) In situ chemistry of osteoporosis revealed by synchrotron infrared microspectroscopy. Bone 33:514-21
Rashidzadeh, Hassan; Khrapunov, Sergei; Chance, Mark R et al. (2003) Solution structure and interdomain interactions of the Saccharomyces cerevisiae ""TATA binding protein"" (TBP) probed by radiolytic protein footprinting. Biochemistry 42:3655-65
Uchida, Takeshi; Takamoto, Keiji; He, Qin et al. (2003) Multiple monovalent ion-dependent pathways for the folding of the L-21 Tetrahymena thermophila ribozyme. J Mol Biol 328:463-78
Taylor, Colleen M; Watton, Stephen P; Bryngelson, Peter A et al. (2003) Inner-sphere complexation of cobalt(II) 2,9-dimethyl-1,10-phenanthroline ([Co(neo)]2+) with commercial and sol-gel derived silica gel surfaces. Inorg Chem 42:312-20
Marinkovic, N S; Huang, R; Bromberg, P et al. (2002) Center for Synchrotron Biosciences' U2B beamline: an international resource for biological infrared spectroscopy. J Synchrotron Radiat 9:189-97
Huang, R Y; Miller, L M; Carlson, C S et al. (2002) Characterization of bone mineral composition in the proximal tibia of cynomolgus monkeys: effect of ovariectomy and nandrolone decanoate treatment. Bone 30:492-7
Dewan, John C; Feeling-Taylor, Angela; Puius, Yoram A et al. (2002) Structure of mutant human carbonmonoxyhemoglobin C (betaE6K) at 2.0 A resolution. Acta Crystallogr D Biol Crystallogr 58:2038-42
Kiselar, J G; Maleknia, S D; Sullivan, M et al. (2002) Hydroxyl radical probe of protein surfaces using synchrotron X-ray radiolysis and mass spectrometry. Int J Radiat Biol 78:101-14

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