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PET Film (pet + film)
Selected AbstractsPrintable Yagi antenna with closely spaced elementsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2007Sungkyun Lim Abstract A two-element, planar Yagi antenna with closely spaced elements is reported. Multiple folding in the driver is used to boost up the low radiation resistance due to the close spacing between the driver and the director. The antenna dimensions are first optimized in wire form and then transferred into a printed version on PET film. A prototype planar monopole Yagi is built and measured at 1 GHz. The maximum realized gain of the antenna on 50-,m PET film is measured to be 9.56 dB. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2106,2109, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22660 [source] Deposition of 90YPO4 and 144CePO4 radioisotopes on polymer surfaces for radiation delivery devicesJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2002Xin Qu Abstract Intravascular irradiation with , emitters inhibits restenosis in arteries after balloon angioplasty or stent implantation. Yttrium-90 (90Y, T1/2=64 h) and cerium-144 (144Ce, T1/2=286 d) emit beta particles (Emax=2.28,3.50 MeV) having an ideal energy range for brachytherapy delivery system. In this article, a previously reported method for depositing 32P on poly(ethylene terephtalate) (PET) surfaces is generalized and modifications that allow deposition of other ,-emitting radioisotopes, such as 90Y and 144Ce, are demonstrated. PET films were first coated with chitosan hydrogel and then adsorbed different amounts of phosphoric acid (PA) in aqueous solutions. Yttrium was deposited onto the surface as YPO4 after the films were immersed in YCl3 solutions. 1 ,Ci 90YCl3 (2×10,9 g) was used in each sample as a tracer for measuring the deposition efficiency, which is defined as the percentage of YCl3 deposited on the surface compared to the amount of YCl3 in solutions before the deposition. In order to improve the safety of brachytherapy treatments, polyurethanes were used to seal the deposited radioisotopes on the surface to minimize the leakage of the isotopes into the patients. The generality of this method presented here for a wide variety of particular radioisotopic components allows design of a broad range of versatile radioisotope sources. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 98,105, 2002; DOI 10.1002/jbm.10095 [source] Role of structural modification on the electrical properties of poly(ethylene terephthalate) irradiated with 90-MeV carbon ion beamPOLYMER ENGINEERING & SCIENCE, Issue 6 2008A. Srivastava Thin films of poly(ethylene terephthalate) (PET) having a thickness of 100 ,m were exposed to different ion fluence of swift heavy ions of carbon in the range of 5 × 1011 , 5 × 1013 ions/cm2. The effect of ion beam on structural and electrical modification has been studied by UV/vis, FTIR, X-ray diffraction (XRD), Differential Scanning Calorimetery (DSC), and AC electrical measurement techniques. On irradiation, a shift in absorption wavelength toward the red end of spectrum with increase of ion fluence was observed. The intensity of crystalline IR bands and main diffraction peak in XRD pattern were found to decrease with increase in ion fluence. It indicates the loss of crystallinity induced by ion-beam irradiation. The crystallite size was found to increase on irradiation. The melting temperature (Tm) of PET films increased at a low ion dose (5.0 × 1012 ions/cm2), while it decreased at higher ion fluence (50.0 × 1012 ions/cm2). The dielectric constant (,,) of PET films was increased with increase of ion fluence. The modifications brought about in the dielectric constant are correlated with chemical and molecular structural changes occurring on irradiation. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers. [source] | ||||||||||