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Deposition
Kinds of Deposition Terms modified by Deposition Selected AbstractsLANDSLIDE INITIATION, RUNOUT, AND DEPOSITION WITHIN CLEARCUTS AND OLD-GROWTH FORESTS OF ALASKA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2000A. C. Johnson ABSTRACT: More than 300 landslides and debris flows were triggered by an October 1993 storm on Prince of Wales Island, southeast Alaska. Initiation, runout, and deposition patterns of landslides that occurred within clearcuts, second-growth, and old-growth forests were examined. Blowdown and snags, associated with cedar decline and "normal" rates of mortality, were found adjacent to at least 75 percent of all failures regardless of land use. Nearly 50 percent of the landslides within clearcuts occurred within one year following timber harvest; more than 70 percent of these sites had hydrophytic vegetation directly above failures. In following the runout paths of failures, significantly more erosion per unit area occurred within clearcuts than in old-growth forests on slopes with gradients from 9 to 28* (16 to 54 percent). Runout length, controlled by hillslope position within deglaciated valleys, was typically longer in old-growth forests than in second growth and clearcuts (median values were 334, 201, and 153 m, respectively). Most landslides and debris flows deposited in first-and second-order channels before reaching the main stem channels used by anadromous fish. Slide deposits in old-growth forests were composed of a higher proportion of woody debris than deposits derived from slides in second growth or clearcuts. [source] AMINOGUANIDINE AMELIORATES OVEREXPRESSION OF PROSCLEROTIC GROWTH FACTORS AND TYPE IV COLLAGEN DEPOSITION IN EXPERIMENTAL DIABETIC NEPHROPATHYNEPHROLOGY, Issue 3 2000Gilbert Re [source] POTS AND PITS: DRINKING AND DEPOSITION IN LATE IRON AGE SOUTH-EAST BRITAINOXFORD JOURNAL OF ARCHAEOLOGY, Issue 2 2005MARTIN PITTS Summary. This paper considers the role of pottery in the Late Iron Age to Roman transition in south-east Britain. Traditional concern with the significance of Continental imports is rejected in favour of a more holistic and bottom-up approach giving equal emphasis to locally made forms and imports in complete assemblages. Several stages of inter-site correspondence analysis are conducted on a range of sites and assemblages in the region. Patterning pertaining to the use and deposition of both imported and local pottery vessels can be seen to contradict simplistic models for ,Romanization before conquest'. The main conclusions include evidence for the selective disposal of drinking vessels and table wares in pits, the likely widespread consumption of beer as opposed to wine, and the implied importance of indigenous social practices such as feasting and communal drinking. [source] Preparation of undoped and indium doped ZnO thin films by pulsed laser deposition methodCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2005B. Kotlyarchuk Abstract An original modification of the standard Pulse Laser Deposition (PLD) method for preparing both undoped and indium doped zinc oxide (ZnO:In) thin films at low substrate temperature is proposed. This preparation method does not demand any further post-deposition annealing treatment of the grown films. The developed method allows to grow thin films at low substrate temperature that prevents them from the considerable loss of their intrinsic electrical and optical properties. The influence of deposition parameters on the electrical and optical parameters of the undoped and the indium doped ZnO thin films is also analysed. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Optimization of Cr8O21 targets for Pulsed Laser DepositionCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2005L. Tortet Abstract This work describes the preparation of Cr8O21 pellets with optimised mass density to be used as targets for Pulsed Laser Deposition (PLD) of chromium dioxide thin films. Cr8O21 is synthesised by thermal decomposition of CrO3, at 270 °C. An attempt to reduce the grain size of the Cr8O21 powder to the nanometer scale has been made in order to increase the density of the pressed and sintered pellets serving as targets. The morphology of those starting fine powders as well as of targets (before and after laser ablation) and the corresponding thin films were characterized and studied using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Raman spectroscopy. The composition of the films is a mixture of crystallised Cr2O3 and amorphous CrO2. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Nanocrystalline non-planar carbons: Growth of carbon nanotubes and curled nanostructuresCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10-11 2005S. Orlanducci Abstract We present a variety of non-planar graphitic nanostructures selectively generated in a modified Hot-Filament Chemical Vapour Deposition (HF-CVD) apparatus, using purpose-synthesized amorphous carbon nanoparticles or graphite powders as solid state precursor. The employed methodologies enable to successfully synthesize homogeneous and well organized deposits of single- and multi-walled carbon nanotubes, onion-like nanostructures, and nanotube bundles coated by nano-sized diamond grains. Variations in the morphological aspect of such non-planar graphite-based nanostructures are observed changing the experimental conditions: the solid state reactants, the filament and substrate temperatures, the catalyst concentration, and the atomic hydrogen flux over the substrate play key roles in the phenomenon. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Morphological, structural and optical study of quasi-1D SnO2 nanowires and nanobeltsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10-11 2005D. Calestani Abstract 0.1,0.3 mm thick entanglements of quasi-one-dimensional semiconducting Tin dioxide nanocrystals, in form of nanowires and nanobelts, are successfully grown by low cost Chemical Vapour Deposition directly on large area (100 mm2) Al2O3, SiO2 and Si substrates. Their lateral size ranges from 50 to 700 nm and their length can achieve several hundreds of micrometers. Transmission Electron Microscopy reveals either the nanowires and the nanobelts grow in the tetragonal Rutile structure. Diffraction contrast analyses and selected area diffraction investigations show the nanowires are single crystals without defects while the nanobelts sometimes present twins inside. An almost cylindrical shape and an average diameter of about 30,50 nm for the smallest nanowires is reported. X-ray diffraction investigations exclude the presence of spurious phases. A broad band structured in two emissions peaked at about 450 nm and 560 nm is revealed by large area Cathotoluminescence, while single nanocrystal spectroscopy shows that the reduction of the lateral dimension of the nanobelts from 1000 nm to 50 nm blue-shifts the main emission band at 560 nm of about 40 nm (at room temperature). These preliminary results suggest a possible role of oxygen vacancies and of the surface/volume ratio on the origin and the blue shift of Cathodoluminescence spectra. The near band edge emission, typical of bulk tin dioxide (,320 nm), is not found in nanobelts narrower than 1000 nm. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Spatial and temporal variations in bank erosion on sand-bed streams in the seasonally wet tropics of northern AustraliaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 9 2006M. J. Saynor Abstract Bank erosion rates and processes across a range of spatial scales are poorly understood in most environments, especially in the seasonally wet tropics of northern Australia where sediment yields are among global minima. A total of 177 erosion pins was installed at 45 sites on four sand-bed streams (Tributaries North and Central, East Tributary and Ngarradj) in the Ngarradj catchment in the Alligator Rivers Region. Bank erosion was measured for up to 3·5 years (start of 1998/99 wet season to end of 2001/02 wet season) at three spatial scales, namely a discontinuous gully (0·6 km2) that was initiated by erosion of a grass swale between 1975 and 1981, a small continuous channel (2·5 km2) on an alluvial fan that was formed by incision of a formerly discontinuous channel between 1964 and 1978, and three medium-sized, continuous channels (8·5,43·6 km2) with riparian vegetation. The bank erosion measurements during a period of average to above-average rainfall established that substantial bank erosion occurred during the wet season on the two smaller channels by rapid lateral migration (Tributary Central) and by erosion of gully sidewalls due to a combination of within-gully flows and overland flow plunging over the sidewalls (Tributary North). Minor bank erosion also occurred during the dry season by faunal activity, by desiccation and loss of cohesion of the sandy bank sediments and by dry flow processes. The larger channels with riparian vegetation (East Tributary and Ngarradj) did not generate significant amounts of sediment by bank erosion. Deposition (i.e. negative pin values) was locally significant at all scales. Bank profile form and channel planform exert a strong control on erosion rates during the wet season but not during the dry season. Copyright © 2006 Commonwealth Government of Australia. [source] Current-Free Deposition of Prussian Blue with Organic Polymers: Towards Improved Stability and Mass Production of the Advanced Hydrogen Peroxide TransducerELECTROANALYSIS, Issue 3-5 2009Anastasiya Abstract We report on a novel approach for open-circuit (current-free) deposition of Prussian blue. Synthesis of Prussian blue is carried out by reduction of ferric ferricyanide with organic molecules, which are known to form polymers upon oxidation. The proposed interfacial deposition is a result of the synthesis in the presence of electrode support due to preconcentration of precursors at the interface. The resulting modified electrodes displayed the dramatically improved operational stability in hydrogen peroxide continuous monitoring with no loss of either electrochemical or analytical performance characteristics compared to electrodes with electrochemically deposited Prussian blue. The shown possibility to deposit stable films with regular structure in the absence of any external voltage could open new horizons for sensor science. [source] Electrostatic Assembly of a Redox Catalysis System for Detection of GlutamateELECTROANALYSIS, Issue 24 2006Alice Abstract Interfacial assemblies capable of determining glutamate by redox catalysis are prepared by electrostatic assembly of alternating layers of ferrocene poly(allylamine) polymer and glutamate oxidase on a gold electrode. Deposition of the polymer was confirmed in cyclic voltammetry measurements by the presence of a surface wave corresponding to the oxidation of the ferrocene group. In the presence of glutamate in the adjacent electrolyte solution, the current increases and approaches a pseudosteady state, consistent with redox catalysis. Electrodes modified with glutamate oxidase had a linear response to glutamate up to 0.0045,M with sensitivity of 20,,A/cm2 and a limit of detection of 31.4,,M glutamate. An apparent Michaelis,Menten constant of 0.40(±0.13),mM for the confined glutamate oxidase was determined for this assembly. When used in flow-injection experiments, glucose oxidase modified electrodes responded to transient zones of glucose; however, the detection limits of the assemblies to the flowing stream were substantially higher than found for measurements on static solutions. [source] Electrochemically-Induced Deposition of Amine-Functionalized Silica Films on Gold Electrodes and Application to Cu(II) Detection in (Hydro)Alcoholic MediumELECTROANALYSIS, Issue 19 2005Alain Walcarius Abstract Well-adherent amine-functionalized porous silica films have been deposited on gold electrodes by combining the self-assembly technology, the sol,gel process, and the electrochemical modulation of pH at the electrode/solution interface. A partial self-assembled monolayer of mercaptopropyl-trimethoxysilane (MPTMS) was first formed on disposable gold electrodes from recordable CDs (Au-CDtrodes). The so pretreated MPTMS-Au-CDtrodes were immersed in a stable sol solution (pH,3) containing (3-aminopropyl)-triethoxysilane (APTES) and tetraethoxysilane (TEOS). Polycondensation of the APTES and TEOS precursors was then achieved by applying a negative potential for a given period of time to generate a local pH increase at the electrode/solution interface and promote the deposition of the amine functionalized silica film adhering well to the electrode surface owing to the MPTMS monolayer acting somewhat as a "molecular glue". Various parameters affecting the electrodeposition process have been studied and the film permeability to redox probes in solution was characterized by cyclic voltammetry. The amine-functionalized silica film electrodes were then applied to the preconcentration of copper(II) species prior to their electrochemical detection by anodic stripping differential pulse voltammetry. Getting high sensitivity has however required the application of an electrochemical pre-activation step as the majority of the organo-functional groups were in the form of ammonium moieties (because the film was prepared from an acidic sol). This was achieved by applying a sufficiently negative potential to the electrode surface to reduce protons and increase consequently the amine-to-ammonium ratio within the film and, thus, the efficiency of the precocentration process. The resulting device was then optimized for copper(II) determination in hydroalcoholic medium, giving rise to a linear response in the 0.1,10,,M concentration range. [source] Organic Phase PPO Biosensors Prepared by Multilayer Deposition of Enzyme and Alginate Through Avidin-Biotin InteractionsELECTROANALYSIS, Issue 24 2004S. Cosnier Abstract Films of electrogenerated polypyrrole and hydrophilic alginate, both functionalized with biotin moieties, were used to allow for the transfer of polyphenol oxidase activity in organic media. Enzyme electrodes, based on multilayered structures, were protected at the molecular level by the affinity binding of alginate as a hydrophilic additive, and were then transferred into chlorobenzene, dichloromethane, chloroform, ethyl acetate or acetonitrile. The biosensor performance for the detection of catechol at ,0.2,V was investigated, highlighting the main influence of the hydrophobicity of the solvent and, to a lesser extent, the dielectric constant. The effect of the substrate hydrophobicity on the biosensor response was examined in chlorobenzene. [source] Nb-Doped VO2 Thin Films Prepared by Aerosol-Assisted Chemical Vapour DepositionEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 25 2007Clara Piccirillo Abstract Niobium-doped vanadium dioxide (VxNb1,xO2, x = 0,0.037) thin films were prepared by aerosol-assisted chemical vapour deposition (AACVD) of vanadyl(IV) acetonate and niobium(V) ethoxide in ethanol. Samples were analysed by EDX, XRD, Raman, XPS and SEM. The analyses confirmed the deposition of niobium, even if no separated phase was formed; the morphological structure of the films was affected by the dopant presence. The thin films showed thermochromic behaviour, with a marked change in optical properties above and below the switching temperature. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Tungsten Oxide and Tungsten Oxide-Titania Thin Films Prepared by Aerosol-Assisted Deposition , Use of Preformed Solid NanoparticlesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2007Uzma Qureshi Abstract Aerosol-assisted deposition (AAD) was used to deposit films of WO3 from a suspension of solid nanoparticulate WO3 in toluene. Titania films were deposited by the aerosol-assisted chemical vapour deposition of [Ti(OiPr)4] in the presence of WO3 nanoparticles. The WO3 and TiO2 films exhibited photoactivity and photoinduced superhydrophilicity, further the titania films showed very unusual highly crenulated microstructures. These microstructures could not be obtained by sol-gel, atmospheric pressure chemical vapour deposition or evaporation routes. Furthermore, the microstructures could not be obtained from [Ti(OiPr)4] in the absence of nanoparticulate WO3. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Apatite Deposition on NaOH-Treated PEEK and UHMWPE Films for Sclera Materials in Artificial Cornea Implants,ADVANCED ENGINEERING MATERIALS, Issue 7 2010Monica Pino Abstract Cornea implants consist of a clear optic portion with a surrounding ring known as the skirt, which needs to integrate with the sclera. However, currently used skirt materials lead to poor tissue integration. Improvements in this respect may be achieved by using a bioactive skirt material that adapts to the metabolic activity of the cornea. Polyether etherketone (PEEK) and ultra-high molecular weight polyethylene (UHMWPE) might provide interesting alternatives, if they can be rendered bioactive. We, therefore, investigated the potential of surface-modifying PEEK and UHMWPE films through the use of a two-step treatment. This process involved a suitable chemical surface modification (via immersion in NaOH), with subsequent formation of apatite layers on the polymers' surfaces through exposure to supersaturated simulated body fluid (1.5 SBF). In the present work the effect of 5 and 10,M NaOH on formation of the apatite layer has been investigated with regard to wettability and topography features. In addition, the chemical stability of the apatite layer formed has been analyzed. Our data demonstrate that with an increase in NaOH concentration the wettability of the polymer increased, whilst some changes to the polymer film topography (increase/decrease in roughness) were observed. Most beneficially, the apatite layer that subsequently was grown on pre-treated PEEK and UHMWPE films through immersion in 1.5 SBF contained phosphate and carbonate ions, in similar ratios to those found in the apatite in dentine, thus, promising good in vivo bioactivity of these polymer films,a necessity if they are to be integrated into artificial cornea. [source] Tin-containing fluoride solutions as anti-erosive agents in enamel: an in vitro tin-uptake, tissue-loss, and scanning electron micrograph studyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2009Nadine Schlueter Tin-containing fluoride solutions can reduce erosive tissue loss, but the effects of the reaction between tin and enamel are still not clear. During a 10-d period, enamel specimens were cyclically demineralized (0.05 M citric acid, pH 2.3, 6 × 5 min d,1) and remineralized (between the demineralization cycles and overnight). In the negative-control group, no further treatment was performed. Three groups were treated (2 × 2 min d,1) with tin-containing fluoride solutions (400, 1,400 or 2,100 ppm Sn2+, all 1,500 ppm F,, pH 4.5). Three additional groups were treated with test solutions twice daily, but without demineralization. Tissue loss was determined profilometrically. Energy-dispersive X-ray spectroscopy was used to measure the tin content on and within three layers (10 ,m each) beneath the surface. In addition, scanning electron microscopy was conducted. All test preparations significantly reduced tissue loss. Deposition of tin on surfaces was higher without erosion than with erosion, but no incorporation of tin into enamel was found without demineralization. Under erosive conditions, both highly concentrated solutions led to the incorporation of tin up to a depth of 20 ,m; the less-concentrated solution led to small amounts of tin in the outer 10 ,m. The efficacy of tin-containing solutions seems to depend mainly on the incorporation of tin into enamel. [source] Electrolytic Deposition of Hydroxyapatite Coating on CoNiCrMo SubstratesADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Dong-Yang Lin Hydroxyapatite (HA) coating was fabricated on CoNiCrMo alloy by electrolytic deposition (ELD). Different kinds of uncharged substrates were placed close to the cathode separately during the ELD process. Both CoNiCrMo and uncharged substrates were covered with uniform HA coatings composed of hexagonal prism crystals after 60,min deposition. The pH value of the bulk solution changed hardly while the local pH had a sharp increase after ELD. The results demonstrate the local pH plays a crucial role in the ELD process. [source] In situ Grazing Incidence Scattering Investigations During Magnetron Sputtering Deposition of FePt/Ag Thin Films (Adv. Eng.ADVANCED ENGINEERING MATERIALS, Issue 6 2009Mater. The cover picture shows an grazing incidence small angle X-ray scattering pattern of a granular Ag(6nm)-FePt(7.5nm)-Ag-FePt thin film using an in-situ magnetron sputtering chamber measured directly after growth at the Beamline BM20 (ROBL) at the ESRF. The sequential deposition provides separated, faceted FePt nanoislands without any magnetic property degradation and with magnetic moments preferentially oriented parallel to layer surface. The central part of the picture was blocked by a beam stop to avoid an over-saturation of the CCD detector. More details can be found in the article by Jörg Grenzer et al. on page 478. [source] In situ Grazing Incidence Scattering Investigations During Magnetron Sputtering Deposition of FePt/Ag Thin Films,ADVANCED ENGINEERING MATERIALS, Issue 6 2009Valentina Cantelli Using in situ synchrotron X-ray grazing incidence scattering experiments we investigated FePt islands mediated by Ag. FePt has been deposited by DC-magnetron sputtering on amorphous Si/SiO2 substrate at 400,°C, to support the formation of the hard ferromagnetic L10 -FePt phase during growth. The sequential Ag/FePt deposition provides separated FePt nanoislands without magnetic property degradation. We obtained magnetic moments preferentially oriented parallel to layer surface. [source] Atomic Layer Deposition of High- k Oxides of the Group 4 Metals for Memory Applications (Adv. Eng.ADVANCED ENGINEERING MATERIALS, Issue 4 2009Mater. The cover shows high temperature XRD patterns of a 5.8 nm thick HfO2 film and 7.3 nm yttrium-doped HfO2 grown by atomic layer deposition (ALD). More details can be found in the article of J. Niinistö et al. where recent development in ALD of high-k dielectric oxides for memory applications is reviewed on page 223. [source] Atomic Layer Deposition of High- k Oxides of the Group 4 Metals for Memory Applications,ADVANCED ENGINEERING MATERIALS, Issue 4 2009Jaakko Niinistö Abstract This paper reviews several high-k ALD processes potentially applicable to the production of capacitors, concentrating on very recent developments. A list of the dielectric materials under investigation consists of the oxides of several metals, including the Group 4 (Ti, Zr, Hf) elements. The binary oxides of Group 4 metals, as well as their mixtures with other oxides, doped hosts, or multi-layers in the form of nano-laminates are of interest.Several examples of our recent results are shown, including possible ALD routes to materials not previously grown, as well as advances in process development. [source] Nanotechnology Applied on Hot Forging DiesADVANCED ENGINEERING MATERIALS, Issue 7 2008H.-C. The life time of the forging dies still remains a concern and plays an important role on the costs of this process. Latest developments achieved with nanotechnology have proven that thin coatings applied on the surface of the hot forging dies bring technical and economical gains. PVD (Physical Vapor Deposition) deposition processes have confirmed their potential to substantially improve the wear resistance of the hot forging dies. [source] Multi-walled Carbon Nanotube-Reinforced Hydroxyapatite Layers on Ti6Al4V Medical Implants by Electrophoretic Deposition (EPD),ADVANCED ENGINEERING MATERIALS, Issue 1-2 2008C. Kaya Sol-gel synthesised nano-size hydroxyapatite (HA) powders were dispersed in water-based suspensions with the addition of multi-walled carbon nanotubes. Ti6Al4V medical alloys were coated with monolithic and carbon nanotube-reinforced HA using electrophoretic deposition (EPD) in an attempt to control deposit structure and thickness. It was shown that the sintering temperature of the deposited HA layers was significantly lowered by the use of sinter active nano-powders. Moreover the addition of carbon nanotubes increased the bonding strength of the EPD-formed layers to the metallic substrate. The cost-effective EPD technique used in the present work has high industrial potential for coating metallic medical implants with composite bioactive layers. [source] Deposition of chromatin-IgG complexes in skin of nephritic MRL-lpr/lpr mice is associated with increased local matrix metalloprotease activitiesEXPERIMENTAL DERMATOLOGY, Issue 8 2010Annica Hedberg Please cite this paper as: Deposition of chromatin-IgG complexes in skin of nephritic MRL-lpr/lpr mice is associated with increased local matrix metalloprotease activities. Experimental Dermatology 2010; 19: e265,e274. Abstract:, Chromatin-IgG complexes appear as electron dense structures (EDS) in glomerular basement membranes in lupus nephritis. Here, we present results of comparative analyses of the composition of EDS in murine lupus dermatitis and nephritis. One focus was to perform an analytical approach to understand why such complex structures bind skin basement membrane components. Transcription of skin membrane-encoding genes was analysed to see if expression of such genes was increased, eventually indicating that binding capacity of immune complexes increased when dermatitis developed. Variations in matrix metalloprotease 2 (MMP2), MMP9 and Dnase1 mRNA levels and enzymatic activities were correlated with circulatory chromatin-IgG complexes and deposition in skin. We also examined if glomerular deposits of EDS predicted similar deposits in skin of (NZB × NZW)F1 or MRL-lpr/lpr mice, as we observed chromatin-IgG complexes in capillary lumina in skin and glomeruli in both strains. EDS consisting of chromatin fragments and IgG were found sub-epidermally in skin with LE-like lesions of end-stage nephritic MRL-lpr/lpr mice. Dermal MMP-encoding genes were up-regulated during disease progression, and gelatinolytic activity was increased in affected skin. Dnase1 mRNA level and total nuclease activity remained stable in skin during the disease, in contrast to progressive loss of renal Dnase1 mRNA and total renal nuclease activity during development of nephritis. Loss of renal Dnase1 may explain release of chromatin fragments, while increased MMP activity may disrupt membranes making them accessible for chromatin fragment-IgG complexes. Circulatory chromatin-IgG complexes, and up-regulated intradermal MMP activity may be crucial for deposition of immune complexes in skin of lupus-prone mice. [source] Generation Mechanism and in situ Growth Behavior of ,-Iron Nanocrystals by Electron Beam Induced Deposition,ADVANCED ENGINEERING MATERIALS, Issue 8 2006W. Zhang Amorphous iron-containing deposits were formed on carbon films by electron beam induced deposition with a precursor of iron pentacarbonyl and alpha-Fe nanocrystals were grown around the target tip deposits when the electron beam irradiation time was longer than 1000,s. [source] Relationship between Condition of Deposition and Properties of W-Ti-N Thin Films Prepared by Reactive Magnetron Sputtering,ADVANCED ENGINEERING MATERIALS, Issue 3 2006V. Kuchuk A correlation between the film properties of nitrides, oxides etc., and their structure, is of fundamental importance , not only for thin solid films physics but also for practical applications. The structure of the films depends on deposition methods and their parameters. The relationship between properties (chemical and phase compositions, surface morphology, and electrical resistivity) and nitrogen partial pressure of reactive magnetron sputtered W-Ti-N thin films has been discussed here in detail. [source] Tuning the Composition and Nanostructure of Pt/Ir Films via Anodized Aluminum Oxide Templated Atomic Layer DepositionADVANCED FUNCTIONAL MATERIALS, Issue 18 2010David J. Comstock Abstract Nanostructured metal films have been widely studied for their roles in sensing, catalysis, and energy storage. In this work, the synthesis of compositionally controlled and nanostructured Pt/Ir films by atomic layer deposition (ALD) into porous anodized aluminum oxide templates is demonstrated. Templated ALD provides advantages over alternative synthesis techniques, including improved film uniformity and conformality as well as atomic-scale control over morphology and composition. Nanostructured Pt ALD films are demonstrated with morphological control provided by the Pt precursor exposure time and the number of ALD cycles. With these approaches, Pt films with enhanced surface areas, as characterized by roughness factors as large as 310, are reproducibly synthesized. Additionally, nanostructured PtIr alloy films of controlled composition and morphology are demonstrated by templated ALD, with compositions varying systematically from pure Pt to pure Ir. Lastly, the application of nanostructured Pt films to electrochemical sensing applications is demonstrated by the non-enzymatic sensing of glucose. [source] Tuning the Composition and Nanostructure of Pt/Ir Films via Anodized Aluminum Oxide Templated Atomic Layer DepositionADVANCED FUNCTIONAL MATERIALS, Issue 18 2010David J. Comstock Abstract Nanostructured metal films have been widely studied for their roles in sensing, catalysis, and energy storage. In this work, the synthesis of compositionally controlled and nanostructured Pt/Ir films by atomic layer deposition (ALD) into porous anodized aluminum oxide templates is demonstrated. Templated ALD provides advantages over alternative synthesis techniques, including improved film uniformity and conformality as well as atomic-scale control over morphology and composition. Nanostructured Pt ALD films are demonstrated with morphological control provided by the Pt precursor exposure time and the number of ALD cycles. With these approaches, Pt films with enhanced surface areas, as characterized by roughness factors as large as 310, are reproducibly synthesized. Additionally, nanostructured PtIr alloy films of controlled composition and morphology are demonstrated by templated ALD, with compositions varying systematically from pure Pt to pure Ir. Lastly, the application of nanostructured Pt films to electrochemical sensing applications is demonstrated by the non-enzymatic sensing of glucose. [source] Aligning Single-Walled Carbon Nanotubes By Means Of Langmuir,Blodgett Film Deposition: Optical, Morphological, and Photo-electrochemical StudiesADVANCED FUNCTIONAL MATERIALS, Issue 15 2010Gabriele Giancane Abstract An alkoxy-substituted poly(phenylene thiophene) is used in order to suspend single-walled carbon nanotubes in an organic solvent. The suspension is spread on the air,water interface of a Langmuir trough and the floating film is characterized by means of Brewster angle microscopy and UV-visible reflection spectroscopy and the compression isotherm is recorded. The polymer/carbon-nanotube blend is transferred onto different substrates using the Langmuir,Blodgett technique. AFM measurements indicate the formation of globular structures for the samples transferred at low surface-pressure values and a tubular morphology for high-pressure-deposited samples. AFM analysis is repeated on a sample exposed to soft X-rays for about 5,h and a highly organized structure of bundles of carbon nanotubes rises up. Samples with different numbers of layers are transferred onto ITO substrates by means of the Langmuir,Blodgett method and are tested as photocathodes in a photo-electrochemical cell. A Voc of 0.18,V, an Isc of 85.8,mA, FF of 40.0%, and , of (6.23,×,10,3)% are obtained. [source] Electronic Contact Deposition onto Organic Molecular Monolayers: Can We Detect Metal Penetration?ADVANCED FUNCTIONAL MATERIALS, Issue 13 2010Hagay Shpaisman Abstract Using a semiconductor as the substrate to a molecular organic layer, penetration of metal contacts can be clearly identified by the study of electronic charge transport through the layer. A series of monolayers of saturated hydrocarbon molecules with varying lengths is assembled on Si or GaAs and the junctions resulting after further electronic contact is made by liquid Hg, indirect metal evaporation, and a "ready-made" metal pad are measured. In contrast to tunneling characteristics, which are ambiguous regarding contact penetration, the semiconductor surface barrier is very sensitive to any direct contact with a metal. With the organic monolayer intact, a metal,insulator,semiconductor (MIS) structure results. If metal penetrated the monolayer, the junction behaves as a metal,semiconductor (MS) structure. By comparing a molecule-free interface (MS junction) with a molecularly modified one (presumably MIS), possible metal penetration is identified. The major indicators are the semiconductor electronic transport barrier height, extracted from the junction transport characteristics, and the photovoltage. The approach does not require a series of different monolayers and data analysis is quite straightforward, helping to identify non-invasive ways to make electronic contact to soft matter. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||