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Search Results: 1 - 10 of 1966 matches for " films "
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Effect of Composition and Morphology on Sensor Properties of Aerosol Deposited Nanostructured ZnO+In2 O3 Films  [PDF]
Leonid I. Trakhtenberg, Seyed M. Navid Khatami, Genrikh N. Gerasimov, Olusegun J. Ilegbusi
Materials Sciences and Applications (MSA) , 2015, DOI: 10.4236/msa.2015.63026
Abstract: The structural characteristics are investigated of nanoheterogeneous films comprising ZnO, In2 O3 and ZnO + In2 O3 composite produced by aerosol spray pyrolysis technique (SPT). The process utilizes water solutions of zinc chloride and indium nitrate precursors. The X-ray diffraction data show that the SPT process results in polycrystalline films of hexagonal wurtzite type ZnO, and In2 O3 crystals of cubic structure. SPT-synthesized ZnO + In2 O3composites contain mixtures of these crystals. The morphology of the synthesized films is studied by scanning electron microscopy as well as the dependence of morphology on the synthesis conditions, specifically the temperature of the aerosol precipitation and the concentration of the precursors in solutions. The characteristics of nucleation and growth of oxide crystals during the synthesis of ZnO + In2 O3 composite films are also considered. The film with the composition 25 wt% ZnO + 75 wt% In2 O3 contains a large number of small crystal aggregates of arbitrary shape with a high density of contacts between the aggregates and are characterized by a homogeneous structure with high dispersion. Such morphology has high specific surface, which favors high sensory response. In addition, in this range of aggregate composition the relationship between the particles of the catalytically active component- ZnO, cleavage of hydrogen molecule, and In2 O3particles with a high concentration of conduction electrons is close to optimal for the maximum sensory effect in the detection of hydrogen.
Bioavailability of Soy Protein and Corn Zein Films  [PDF]
Laura B. Matthews, M. Elizabeth Kunkel, James C. Acton, Amod A. Ogale, Paul L. Dawson
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.210148
Abstract: The in vivo bioavailability of soy protein isolates and corn zein film material before and after film formation by heat/ pressure was determined. The In vitro digestibility of corn zein before and after film formation was also measured. Films were produced from anhydrous protein with 30% glycerol added using a heat-press method with no use of casting solvents or cross-linking agents. Corn zein raw and film material were ground under liquid nitrogen then digested in two enzyme-acid cocktails with free amino acid analysis before and after digestion. The protein efficiency ratio and net protein ratio were determined for both zein and soy protein using a weanling Sprague-Dawley descended rat feeding study. The In vitro digestibility study indicated that the non-heat pressed corn zein was more digestible than the heat pressed zein. However, the in vivo results indicated that corn and soy protein were equally bioavailable whether they were derived from film mixture prior to or after film formation. Both corn zein and soy protein material had lower protein efficiency ratio than the control diet. Furthermore, soy protein films materials had a higher protein efficiency ratio than corn zein.
Intense Visible Photoluminescence from C46H22N8O4KM (M = Co, Fe, Pb) Derivatives Thin Films  [PDF]
María Elena Sánchez, Juan Carlos Alonso, Jerry Nathan Reider
Advances in Materials Physics and Chemistry (AMPC) , 2011, DOI: 10.4236/ampc.2011.13010
Abstract: Strong visible photoluminescence (PL) at room temperature is obtained from thermal-evaporated thin solid films of Metallophthalocyanine (M = Co, Fe, Pb) and double potassium salt from 1,8 dihydroxyan-thraquinone. The PL of all the investigated samples is observed with the naked eye in a bright background. The deconvolution of the normalized PL spectra shows that each PL spectrum is composed of four emission bands which peak at approximately the same energies of 2.1, 2.2 and 2.4 eV and whose intensities and widths depend upon the structure of the complexes. FTIR and ellipsometry are employed to investigate the structural differences among the films. The optical absorption of the films is also investigated to evaluate the changes in the electronic structure of these metal organic compounds, with respect to other metalphtalocya-nines thin films. Our results suggest that the visible PL comes from radiative transitions between energy lev-els associated to the double potassium salt coordination to the metallic ion in the phthalocyanine.
Synthesis of Chained Achromatic Layer Systems Forming Controlled Low Transmittance Bands  [PDF]
Mohamed Medhat, Samy S. Farag
Optics and Photonics Journal (OPJ) , 2011, DOI: 10.4236/opj.2011.13021
Abstract: The approach utilized in the design of achromatic periods formed of two layers a high-index and a low-index is developed by combining the first two periods together. These two periods are therefore reduced to three layers a central one, an upper layer and a lower layer. Both the upper and lower layers are matched to the central at two different wavelengths. This forms the so called a combined achromatic period or the basic unit. Multilayers showing low transmittance bands are then synthesized of this basic unit. Parameters used in the synthesis of such multilayers are pointed out and their control role is investigated.
Structural and Optical Properties of Li+: PVP & Ag+: PVP Polymer Films  [PDF]
Kothapalle Sivaiah, Koramala Naveen Kumar, V. Naresh, Srinivasa Buddhudu
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.211225
Abstract: PVP polymers containing Li+ or Ag+ Ions have been synthesized in good stability and transparency by using the solution casting method. Their structural, optical, thermal and electrical properties have been investigated from the measurement of XRD, FTIR, SEM, EDAX, optical absorption spectra, TG-DTA profiles and impedance spectral features in order to evaluate their potentialities for their use in electrochemical display device applications.
Phase Transformations in PZT Thin Films Prepared by Polymeric Chemical Method  [PDF]
Elton C. Lima, Eudes Borges Araújo
Advances in Materials Physics and Chemistry (AMPC) , 2012, DOI: 10.4236/ampc.2012.23027
Abstract: Lead zirconate titanate Pb(Zr0.50Ti0.50)O3 (PZT) thin films were deposited by a polymeric chemical method on Pt(111)/ Ti/SiO2/Si substrates to understand the mechanisms of phase transformations in these films. PZT films pyrolyzed at temperatures higher than 350℃ present a coexistence of pyrochlore and perovskite phases, while only perovskite phase is present in films pyrolyzed at temperatures lower than 300℃. For films where the pyrochlore and perovskite phase coexists the amount of pyrochlore phase decreases from top surface to the bottom film-electrode interface and the PZT structure near top surface are Ti-rich compositions while near the bottom film-electrode interface the compositions are Zr-rich. For pyrochlore-free PZT thin film, a small (100) orientation tendency near the film-electrode interface was observed.
The Cytocompatibility of Genipin-Crosslinked Silk Fibroin Films  [PDF]
Lingshuang Wang, Yiyu Wang, Jing Qu, Yongpei Hu, Renchuan You, Mingzhong Li
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2013, DOI: 10.4236/jbnb.2013.43026

There is an increasing demand for crosslinking methods of silk fibroin (SF) scaffolds in biomedical applications that could maintain the biocompatibility, bioactivity as well as improve the water resistance and mechanical properties of SF materials. In this study, SF was crosslinked effectively with genipin which is a naturally occurring iridoid glucoside and the crosslinking mechanism was investigated through FTIR and amino acid analysis. The results showed that genipin could react with the -NH2 groups on the side chains of SF macromolecules and to form inter- and intra-molecular covalent bonds, and improved the stability of SF materials significantly. In vitro, the performances of genipin-crosslinked SF films were assessed by seeding L929 cells and compared with ethanol-processed SF films, glutaraldehyde and polyethylene glycol diglycidyl ether crosslinked ones. The genipin-crosslinked SF films showed a similar affinity to cells as ethanol-processed ones, and a higher bioactivity in promoting cell growth and proliferation, inhibition of cell apoptosis, and maintenance of normal cell cycle compared with glutaraldehyde and polyethylene glycol diglycidyl ether crosslinked SF films. These features, combined with the decrease of brittleness of SF films crosslinked with chemical methods, substantiated genipin as an effective and biocompatible agent for the manufacturing of bioactive SF materials which used as tissue engineering scaffolds and drug delivery carriers.

Doped Amorphous Carbon Films Prepared by Liquid Phase Electrodeposition  [PDF]
Canyan Che, Yang Li, Guifeng Zhang, Dewei Deng
Open Journal of Synthesis Theory and Applications (OJSTA) , 2014, DOI: 10.4236/ojsta.2014.31002

It has theoretical significance and practical value to synthetize and modify amorphous carbon films by liquid electro-deposition technique due to its low cost, simple equipment, and better operability in uniform deposition of the films with large-area and complex shape work pieces. This article introduces the research situation of the carbon films prepared by liquid phase electrochemical deposition according to the applied voltage, discusses the influence of experimental parameters on the film properties, and describes possible reaction mechanisms. It summarizes the research progress of amorphous carbon films doped with metal and nonmetals. Finally, existing problems have been demonstrated and suggestions on research hotspots in the future are given.

Electrical And Thermal Coatings From A Single-Walled Carbon Nanotube (SWCNT)/Polymer Composite  [PDF]
Gerard T. Caneba, Jay Axland
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2004, DOI: 10.4236/jmmce.2004.32008
Abstract: Single-walled carbon nanotubes (SWCNTs) are uniquely suitable as lightweight electrically and thermally conductive materials. However, due to their tendency to agglomerate into fiber bundles and relatively weak adhesion to other materials, it has always been a challenge to process these materials for various applications. Solvents and additives with relatively strong specific intermolecular forces were proposed to be required to effect SWCNT dispersion along with the application of ultrasound. This work involved the use of this hypothesis, in order to disperse SWCNTs with an acid-containing copolymer that also served as a binder for the solid composite. In particular, HiPco was dispersed in DMF ant THF using a tapered vinyl acetate-acrylic acid (VA-t-AA) block copolymer with 6 wt % AA content. Dispersions were cast onto films and resulted in solid coatings that have good electrical and thermal conductive and capacitive properties.
REVIEW: The Not-Too-Subtle Psy-War in War Films
Arnold Molina Azurin
Kasarinlan : Philippine Journal of Third World Studies , 2001,
Abstract: A review of war films.
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