Glasses analysis strategy

Perkins, W. T., Pearce, N. J. G., and Westgate, J. A. (1997). The development of laser ablation ICP-MS and calibration strategies examples from the analysis of trace elements in volcanic glass shards and sulfide minerals. Geostandards Newsletter 21 175-190. 

Figure 11.9 Schematic view of the experimental strategy for carrying out poly(Phe) synthesis in POPC liposomes, (i) Freeze-thaw (x 7) solution containing t-RNAP , poly(U), Phe, ATP, GTP, Mg(OAc)2, NH4CI, spermine, spermidine, phos-phoenolpyruvate. (ii) Soution containing pyruvate kinase, 100 000 g supernatant enzymes, 308 and SOS ribosomal subunits, (iii) 1. Free-thaw (x3) 2. Brief extrusion 3. Addition of EDTA (final concentration = 35 mM. (iv) Withdrawl of aliquots at indicated time and cold TCA precipitation. Analysis of the radioactivity remaining on the glass filter by p-scintillation counting. (Modified from Oberholzer et al, 1999.)...

Abstract Modern solid state nuclear magnetic resonance presents new powerful opportunities for the elucidation of medium range order in glasses in the sub-nanometer region. In contrast to standard chemical shift spectroscopy, the strategy presented here is based on the precise measurement and quantitative analysis of internuclear magnetic dipole-dipole interactions, which can be related to distance information in a straightforward manner. The... 

As mentioned earlier, the magnitude of EOF on PT devices is 10 times lower than that in common microfabrication substrates such as glass, quartz, and PDMS. While the EOF in these popular materials can be raised by chemical or physical modification of the surface (activation by oxygen plasma or sodium hydroxide), similar treatment of PT chips does not yield the same enhancement. The use of sodium hydroxide is not recommended because it attacks the toner surface rapidly (in a few minutes), even at low concentration. However, the low EOF can certainly be an advantage for the analysis of analytes with similar electrophoretic mobilities. One strategy to obtain a simple microdevice but with greater EOF is the fabrication of glass-toner microchips. ... 

An alternative strategy is appropriate if determinations are to comply with a standard scheme of analysis, such as those developed by the British Standards Institution for the analysis of ceramic and refractory materials. In these schemes, samples are prepared as fused glass disks and calibration samples may then be prepared in the same way using specified proportions of high-purity element oxides. This calibration procedure can, therefore, be considered to be absolute in contrast to the relative measurements made against reference samples. 

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