Metallic glasses formation

BULK METALLIC GLASS FORMATION IN THE Pd-Ni-P and Pd-Cu-P ALLOY SYSTEMS... 

Y. G. Chen, B. X. Liu, Different Driving Force for Metallic Glass Formation Nb-Ni and Nb-Y Systems by Ion Mixing and Solid-State Reaction,... 

Tellurium, which has more metallic character, is not able to support a polymeric arrangement in its hquid phase, which has a low viscosity like a molten metal. Glass formation is only possible from Tei Se solutions, and even then very fast quenching such as melt spinning is needed. 

W. L. Johnson Fundamental aspects of bulk metallic glass formation in multicomponent alloys. Mater. 

It is worth noting here that the first alloy found to exhibit metallic glass formation was the binary Au-Si eutectic composition. It was argued that the abnormal behavior of such alloys is related to... 

Typically, in solution-phase film deposition, a precursor coating is applied to a surface and heated, whereupon the elimination of solvent leads to localized crystallization and separation of solid particles. To prevent these processes, metal-organic precursors can be commonly employed for sol-gel deposition (see Chapter 2), wherein the organic ligands essentially act as vehicles to promote glass formation. Ultimately, embedded organic ligands... 

Crystal approximants. Several crystalline phases contain more or less closely packed atomic assemblies (polyhedra, clusters) which have been considered fundamental constituents of several quasicrystals, metal glasses and liquids. Such crystalline phases (crystal approximants), as reported in the previous paragraph, are often observed in the same (or similar) systems, as those corresponding to the formation of quasicrystals and under similar preparation conditions. Crystalline phases closely related to the quasicrystals (containing similar building blocks) have generally complex structures as approximants to the ico-quasicrystals we may, for instance, mention the Frank-Kasper phases (previously described in 3.9.3.1). 

A schematic view of the cold cathode fabrication process is shown in Fig. 10.18. The cold cathode is fabricated by low pressure chemical vapor deposition (LPCVD) of 1.5 pm of non-doped polysilicon on a silicon wafer or a metallized glass substrate. The topmost micrometer of polysilicon is then anodized (10 mA cnT2, 30 s) in ethanoic HF under illumination. This results in a porous layer with inclusions of larger silicon crystallites, due to faster pore formation along grain boundaries. After anodization the porous layer is oxidized (700 °C, 60 min) and a semi-transparent (10 nm) gold film is deposited as a top electrode. 

M.H. Cohen, D. Turnbull, Composition requirements for glass formation in metallic and ionic systems, Nature 189 (1961) 131-132. 

X.L. Yeh, K. Samwer, W.L. Johnson, Formation of an amorphous metallic hydride by reaction of hydrogen with crystalline intermetallic compounds - a new method of synthesizing metallic glasses, Appl. Phys. Lett. 42 (1983) 242-244. 

Nanospray is a miniaturized version of electrospray. In the original setup of Wilm and Mann (8) it is utilized as an off-line technique using disposable, finely drawn (1 -gm tip), metallized glass capillaries to infuse samples at 10-30 nL/min flow rates. This allows more than 50 min analysis time with just a 1-pT sample. Due to the formation of much smaller droplets and the more effective ionization, there is often no need for LC separation, since the separation is accomplished in m/z or by MS/MS. However, limited reproducibility with respect to quantification and a more complex sample preparation can be seen as drawbacks. An on-line version for hyphenation with capillary and nano-LC as well as CE (slightly modified) is now commercially available. 

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