Copper morphological characteristics

Composite-based PTC thermistors are potentially more economical. These devices are based on a combination of a conductor in a semicrystalline polymer—for example, carbon black in polyethylene. Other fillers include copper, iron, and silver. Important filler parameters in addition to conductivity include particle size, distribution, morphology, surface energy, oxidation state, and thermal expansion coefficient. Important polymer matrix characteristics in addition to conductivity include the glass transition temperature, Tg, and thermal expansion coefficient. Interfacial effects are extremely important in these materials and can influence the ultimate electrical properties of the composite. 

This concept can be also applied for the case of the electrodeposition of copper. As mentioned earlier, the morphology of the copper deposit obtained at cathodic potential of -500 mV/SCE under the parallel field was of cauliflower-like structure (Fig. 12b), while the morphology of the copper deposit obtained without the applied magnetic field had very dendritic structure (Fig. 12a). It is known that dendritic structures are main characteristic of electrodeposition in conditions of full diffusion control, while cauliflower-like structures are a characteristic of a dominant diffusion in mixed control of electrodeposition process.13... 

These are fundamental considerations and are of interest not just to electrochemists and sonochemists, but care must be taken in correctly attributing an apparent shift in an experimentally observed potential under ultrasound. As already mentioned, system parameters and other factors may influence an observation beyond the effect under investigation. Thus there have been reports on the use of the titanium tip of the sonic horn itself, suitably electrically insulated, as the electrode material [50]. Dubbed the sonotrode , this is a clever idea to combine the two active components of a sonoelectrochemical system the authors noted the expected enhancements in limiting currents and an alteration in the morphology of copper electrodeposited from aqueous solution on to the titanium tip, which was the reaction under test. However, although titanium is widely used in sonochemistry because of its low-loss characteristics under vibration, it is not a common electrode material for electroanalysis because of its inferior electron transfer characteristics... 

Some areas in the pipe showed the presence of both green deposits and shiny copper (Fig. 5.53). Pits were present in areas where copper is surrounded by green deposits (Fig. 5.54). The green deposits indicate significant corrosion. The black scale was carefully removed to identify the morphology of the pits (Fig. 5.55). The pits were located at the bottom of a hole. The morphology of the pits appeared to be characteristic of microbiologically influenced corrosion (Fig. 5.56). 

Les] Lesnik, N.D., Minakova, R.V., Khomenko, E.V., Chromium-Copper System Adhesion Characteristics, Doping, the Structure of Phase Boundary and Composites , Powder Metall. Met. Ceram., 40(7-8), 432-440 (2001) (Experimental, Morphology, Phys. Prop., Interface Phenomena, 12)... 

It has also been suggested that the loss of catalytic activity of copper electrodes depends on the crystallographic properties of the electrode, the surface characteristics and the morphology . The rate of methanol synthesis from a 1 1 mixture of CO2 and H2 at a Cu(lOO) single crystal has been measured and a kinetic model has been proposed This model correctly predicts the rates of methanol production in catalysts under industrial conditions. 

The morphology of the silica particles and their structural characteristics are preserved in the template-derived carbons, as presented in SEM images in Fig.1. The carbon replicas, are made up of spherical particles with diameters of 2-10 pm, regardless the carbon precursor. However, when copper was incorporated to the polystyrene carbon precursor, along with the carbon spheres, a bunch of metallic clusters appeared randomly dispersed at the surface of the carbon matrix. SEM micrographs show numerous particle aggregates of metal of a few nm in size. Taking into account the low reduction potential of the pair Cu (Il)/Cu, and the reductive... 

One of the most challenging goals in nanoparticle (NP) research is to develop successful protocols for the large-scale, simple and (possibly) low-cost preparation of morphologically pure NPs with identical properties. Additionally, NPs should be easily stored and manipulated without losing their properties. In this context, we will try to describe comprehensively the Uterature which exists on the preparation of copper nanosized materials, paying attention to all of these key characteristics. 

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