Metallic glasses Preparation

Platinum family metals preparation. The platinum metals (with gold and silver) are commonly found together, and a number of schemes are in current use for their separation. Platinum metals not only are extracted from ores but, due to their high value, are also recovered from a wide range of industrial residues such as Pt, Rh gauze catalysts, defective components from glass industries, etc. 

Many small-scale filters simply consist of a fixed, rigid medium, robust enough to withstand limited pressures, mounted in a suitable housing. These filters, which are also vacuum operated, are used to clarify by depth filtration. Media are composed of sintered metals, ceramics, plastics, or glass. Filters prepared from closely graded and sintered chemical powders are suitable for the sterilization of solutions by filtration on a manufacturing scale. 

The Synthesis and Fabrication of Ceramics for Speciai Appiication 131 17.3.2. Preparation of Giasses for Speciai Applications 17.3.2.6. Glass-Metals Seals... 

Preparation of Glasses for Special Applications 17.3.2.6. Glass-Metals Seals... 

Composition of Municipal Refuse. The experiment was carried out with municipal refuse, as well as with a simulated unclassified municipal refuse prepared by admixing the classified municipal refuse with plastics, glass, metals, etc. The compositions of the respective refuse are shown in Table I. 

Thin films of a blend of poly(sebaic acid) and PLA (Polysciences) on glass are prepared by spin-coating from 1 w/v % solutions in chloroform onto cleaned glass slides. The glass slides are glued with epoxy to the metallic sample holder disc. 

Bulk metallic glasses were prepared in the Pd-Ni-P and Pd-Cu-P systems using a fluxing technique. The formation of bulk amorphous Pd-Cu-P alloys was reported here for the first time. For both alloy systems, bulk glass formation requires maintaining the phosphorus content near 20 at.%. In the Pd-Ni-P system, lO-mm diameter amorphous PdxNigo-xP 20 rods can be formed for 25 x < 60. In the Pd-Cu-P system, 7-mm diameter amorphous Pd Cugg. xPzo rods can be produced for 40 < x 60. 

Less optimistic predictions have been advanced by France et al. (1987), who estimated 3.5 x 10 dB/km for ZrF -based glass fibers at A 2.55 pm, by taking into account the predicted effects of extrinsic absorption such as that due to transition metal ions, certain lanthanide ions and OH ions. The intrinsic value of attenuation has already been achieved in practice for v-Si02 at 0.16 dB/km for A = 1.55 pm(Miyaetal. 1979). Figure 16a shows an actual measurement for a fluoride glass fiber prepared at the Naval Research Laboratory (NRL), Washington, DC, USA... 

M. Nogami and M. Tomozawa, Zi02-Traiisfoniiation Toughened Glass-Ceramics Prepared by the Sol-gel Process from Metal Alkoxides, 7. Am. Ceram. Soc. 69, 99 102 (1986). 

Bunsen worked out a method for the separation of platinum metals (preparation of pure rhodium). He determined the composition, NIg,NH3, of nitrogen iodide, developed a volumetric method of iodimetry, using a solution of sulphurous acid, and worked on water analysis. Bunsen and L. Schischkoff investigated the chemical reactions in the explosion of gunpowder. Bunsen discovered arsenic pentasulphide, and measured the adsorption of carbon dioxide on glass. ... 

The pioneering work of Klemm and Bommer (1937) in which rare earth chlorides were reduced with K metal in a sealed glass tube resulted in a mixture of metal and KCl which they did not separate. They determined the lattice parameters and some of the magnetic properties of the rare earth metals in the presence of the KCl. Nolting et al. (1960) reduced YCI3 with Li vapor in a sealed stainless steel chamber in Ta crucibles. After the reduction of the YCI3 to Y metal was complete, one end of the chamber was cooled. The LiCl salt then distilled away from the Y crystals and condensed in the cool portion of the chamber. The Y was arc melted to consolidate the small crystals. The microstructure of the arc melted metal was clean. However, the interstitial impurity level was about 20 times higher than the laboratory scale metal prepared by the... 

Nogami M, Tomozawa M (1986) Zr02-transformation-toughned glass-ceramics prepared by the sol gel process from metal alkoxides. J Am Ceram Soc 69 99-102... 

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