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Silver Coatings (silver + coating)

Distribution by Scientific Domains

Medical Sciences	40%

Selected Abstracts

Electromechanical Behavior of Nanoscale Silver Coatings on PET Fibers

PLASMA PROCESSES AND POLYMERS, Issue 9 2008
Martin Amberg
Abstract Plasma-assisted deposition of silver films on PET mono- and multifilament fibers provides conductive fibers for wearable electronics. The nanoscale films were prepared in a continuously running low pressure plasma process using an ICM design for sputtering from a silver target combined with a prior RF cleaning step. The electrical resistance of the as-deposited layers was measured in situ enabling an immediate feedback of the electrical properties, the film quality, applied Ag mass, and film thickness. The deposited quantity of Ag mass on the PET fibers was investigated by ICP-OES and was correlated with the electrical resistance of the film. The metallized fibers showed excellent mechanical properties for wearable electronics as demonstrated by tensile properties measurement. [source]

Selectively Deposited Silver Coatings on Gold-Capped Silicon Nanowires for Surface-Enhanced Raman Spectroscopy

CHEMPHYSCHEM, Issue 8 2009
M. Becker Dr.
Abstract Gold caps on silicon nanowires are selectively coated with silver by autometallography (electroless deposition). Changing the conditions of silver deposition, a variety of different coating morphologies can be produced (see figure). The different silver coating morphologies are investigated in terms of their capabilities for surface enhanced Raman scattering (SERS) experiments. Gold caps on silicon nanowires are hemispherical and only a few tens of nanometers in diameter when grown from metal catalysts by the vapor-liquid-solid growth mechanism using chemical vapor deposition. These gold caps are capable of enhancing Raman signals based on the surface-enhanced Raman scattering effect. The Raman signal can be enhanced even further (by at least one order of magnitude) when silver is selectively deposited onto these gold caps by autometallography (electroless deposition). By changing the silver deposition conditions, different coating morphologies can be realized on the gold caps that range from very thin, smooth layers to uneven and extremely rough coatings. The SERS signal enhancement and the spatial homogeneity of the achievable enhancement are compared for the different silver coatings using a model dye molecule. [source]

Bioimaging TOF-SIMS of tissues by gold ion bombardment of a silver-coated thin section

MICROSCOPY RESEARCH AND TECHNIQUE, Issue 6 2004
Håkan Nygren
Abstract The imaging time-of-flight secondary-ion-mass-spectrometry (TOF-SIMS) method was utilized to address the problem of cholesterol localization in rat tissues. Rat kidneys were fixed, cryoprotected by sucrose, frozen, sectioned by cryoultramicrotomy, and dried at room temperature. The samples were either covered with a thin silver layer or analyzed uncovered in an imaging TOF-SIMS instrument equipped with an Au -source. The yield of desorbed secondary ions for some species was up to 600-fold higher after silver coating of the samples. Reference samples of cholesterol were silver-coated and analyzed by TOF-SIMS to define significant peaks, specific for cholesterol. Such peaks were found at m/z = 386 (C27H46O+), m/z = 493 (C27H46O107Ag+), m/z = 495 (C27H46O109Ag+), m/z = 879 (C54H92O2107Ag+), and m/z = 881 (C54H92O2109Ag+). The silver-cationized cholesterol (493 , m/z , 495) signal was localized by imaging TOF-SIMS in the kidney sections and showed a high cholesterol content in the kidney glomeruli. A more diffuse distribution of cholesterol was also found over areas representing the cytoplasm or plasma membrane of the epithelial cells in the proximal tubules of rat kidney. Microsc. Res. Tech. 65:282,286, 2004. © 2005 Wiley-Liss, Inc. [source]

Large Bore Catheters with Surface Treatments versus Untreated Catheters for Vascular Access in Hemodialysis

ARTIFICIAL ORGANS, Issue 7 2004
Rolf Bambauer
Abstract:, Infection, thrombosis, and stenosis are among the most frequent complications associated with blood-contacting catheters. Complications resulting from infection remain a major problem for hemodialysis catheters, with significant numbers of catheters being removed due to catheter-related sepsis. Numerous strategies have been employed to reduce the occurrence of infection and im-prove long-term outcomes, with varying degrees of success. The most important is the careful and sterile handling by the attending staff of the catheters during hemodialysis treatments to minimize or stop a microbial colonization of the skin and the catheter. Another approach is coating the external surface of the catheters with substances which are antibacterial like silver and/or substances with low thrombogenicity like silicone. This investigation reviews results of animal and clinical experiments conducted to assess the efficacy and biocompatibility of silver and silicone coated dialysis catheters. It is concluded that silver coatings can reduce bacterial colonization and occurrence of infection associated with these devices. The catheters employing ion implantation of silicone rubber showed low thrombogenicity. Results of the studies indicate that ion beam based processes can be used to improve thrombus and infection resistance of blood contacting catheters. A new development is the microdomain structured surface (PUR-SMA coated catheters). Preliminary results with these catheters are very encouraging. [source]