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Showing 1 to 20 of 50 for “"Metal particles"”.
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Preparation and Catalytic Properties of Supported Nanoscale Metal Particles
The materials were active catalysts for the decomposition of methanol to CO and H$\sb2,$ but the catalyst derived from $\rm Pt\sb2Ru\sb4(CO)\sb{18}$ displayed enhanced activity and stability. The behavior of these materials as thermal catalysts is expected to relate to their behavior as …
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Disordering of small metal particles in a scanning transmission electron microscope
Small metal particles in the range of a few nanometers in diameter are seen to progressively disorder when the 100 keV electron beam of a Scanning Transmission Electron Microscope (STEM) is held stationary on the particle. The diffraction pattern of the individual particle is seen to progress from …
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Structure and melting of small metal particles observed by stem microdiffraction
… (Au, Au-Ag, Pt) and vapor deposited (Cu) metal particles •1040 Awas swdied by electron microdiffraction in a S1EM. A CCD array recorded the microdiffraction pattems with high sensitivity and dynamic range, and low noise Microdiffraction pattems were classified according to whether they had …
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Structure and melting of small metal particles observed by stem microdiffraction
… (Au, Au-Ag, Pt) and vapor deposited (Cu) metal particles $\approx$10-40 A A was studied by electron microdiffraction in a STEM. A CCD array recorded the microdiffraction patterns with high sensitivity and dynamic range, and low noise Microdiffraction patterns were classified according to …
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In Situ Remediation Of Heavy Metal Contaminated Sediments Using Emulsified Zero-valent Metal Particles
… through direct contact, ingestion of sediment particles, or uptake of dissolved contaminants present in the water. Dredging, the most common remediation technology for heavy metals, exacerbates this process. The in situ use of emulsified metal has been studied for its ability to pull heavy …
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Characterizing the Movement of Contaminant Liquid Metal Particles when subject to Electric Pulses, within the Context of Z-pinch Fusion Reactors
… examines the behavior of contaminant liquid metal particles, known as ejecta, which are expelled from magnetically-accelerated liquid metal surfaces, in Z-pinch fusion reactors. These ejecta present significant contamination risks to plasma fuel in fusion reactors. The study employed a liquid …
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Cross-Linked PDMS Expansion Due to Submersion in Liquid and Supercritical CO2
<p>Characterization of micro/nano-copper particles impregnated Polydimethylsiloxane (PDMS) submersed in supercritical carbon dioxide (scCO2) was studied. The purpose of this investigation was to advance micro-corrosion sensor technology utilizing PDMS and micro-metal particle composite as the …
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Synthesis and Characterization of Pt-Ru-Sn Catalysts
<p>Magnesia-supported trimetallic Pt-Ru-Sn catalysts prepared through a cluster and a conventional synthetic route have been investigated in terms of their structural properties and their catalytic activity for the hydrogenation of citral and crotonaldehyde. FTIR results indicate that the majority …
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Flame synthesis of carbon nanotubes and metallic nanomaterials
… specific approach focused on the formation of metallic nanoparticles in flames; identification of nanotube formation zones, time scales, and transition conditions; characterization of material properties; and the development of a formation mechanism and associated flame-model. Carbon nanotube …
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Employment of metal-modified polyimide to achieve optimum conductance at an aluminum joint
… relating to the use of polyimides modified with metal-ion complexes and metal particles indicate that enhanced conductivity and adhesive strength can be achieved. This research evaluated the employment of metal-modified polyimides to achieve optimum conductance at an aluminum joint. Condensation …
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A scanning tunneling microscopy study of metal films and supported gold particles
… study the surface morphology of small catalyst particles. This is the first application of the STM in the study of supported metal particles. The STM was used to study the surface morphology of Au/Pd films that were sputter deposited onto mica and subsequently sintered in air, as well as …
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Application and Performance of High Entropy Metal Nanoparticles in the Field of Antibacterial
… explores the potential of various different metal particles in antibacterial aspects and reviews a new method for synthesizing high-entropy alloy oxide nanoparticles (HEO NPs), which is expected to possess the advantages of multiple metals while retaining the antibacterial properties of …
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Nuclear magnetic resonance study of the Pt-Rh bimetallic clusters
We report the study of supported Pt-Rh bimetallic catalysts by 195Pt NMR and by 13C NMR of adsorbed CO. The metal particles are sA-soA in diameter. Study of the dependence of the 13CO resonance position as a function of Pt/Rh ratio and particle size shows that Rh is segregated to the surface. Study …
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Nuclear Magnetic Resonance Study of the Platinum - Rhodium Bimetallic Clusters
We report the study of supported Pt-Rh bimetallic catalysts by $\sp{195}$Pt NMR and by $\sp $C NMR of adsorbed CO. The metal particles are 5A-50A in diameter. Study of the dependence of the $\sp $CO resonance position as a function of Pt/Rh ratio and particle size shows that Rh is segregated to the …
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Reduction expansion synthesis for magnetic alloy powders
… Expansion Synthesis (RES), a technique in which metal particles are the product of the rapid heating to approximately 800 degrees Celsius, in inert atmosphere, of physical mixtures of urea, or similar molecules, and metal oxide, hydroxide or nitrates. As shown by scanning electron microscopy and …
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Self-Healing of Open-Circuit Faults in Organic Thin-Film Transistor-Based Flexible Electronics
… are analysed and the chemical treatment of metal particles are explored. The physical modelling of the healing is established, and relations between the healing time with the suspension concentration, electric field, length of open gap, and external resistance are verified by experimental …
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Characterising catalyst preparation: from adsorbed precursor complex to catalyst particle
… be enhanced by the high dispersion of precious metals onto supports. The deposition of metal particles and the structural arrangement they adopt once impregnated on a support is therefore of interest in determining the necessary conditions required for maximum catalyst efficiency. The details of …
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Hybride von Metall-Nanopartikeln mit hochverzweigten Polyethylenimin als lösliche, abtrennbare Katalysatoren
Nanoscale metal colloids have generated significant interest because of their unique chemical and physical surface properties. These metal particles consisting of a few hundred atoms, most of them located at the surface, are not easily stabilized in solution, and controlling their size remain a key …
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Micro and nano composites composed of a polymer matrix and a metal disperse phase.
… were used as polymeric matrices in polymer + metal composites. The concentration of micrometric (Al, Ag and Ni) as well as nanometric particles (Al and Ag) was varied from 0 to 10 %. Composites were prepared by blending followed by injection molding. The resulting samples were analyzed by …
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