Nonroutine techniques

XPS XPS technique is, in principle, a suitable and promising spectroscopic method to investigate the behavior of Ti in minerals, especially in coexistence with Fe, because it detects the binding energies (BE) of photoejected electrons, whose chemical shifts are related to the oxidation state and the chemical environment [111]. However XPS is still a nonroutine technique in the field of mineralogy. This is due mostly to the lack of standards with suitable structure and composition, to... 

Whatever the precise mechanism is, it has been noted that generally polymerizations of vinyl ethers occur rapidly under electrolytic conditions to give high yields of polymer per Faraday of current passed. However, in most cases, only low-molecular-weight polymers are obtained. Until major breakthroughs are made, electrochemical initiation must be regarded as a rather special, nonroutine technique for the polymerization of vinyl ethers. 

GPC has many uses and is a powerful analysis technique for acrylate polymers. With care in selecting solvents and stationary phases, one finds that many polymers can be analyzed successfully. Opportunities always exist to use analytical GPC columns in nonstandard ways (semiprep, HDC, pseudo-ElPLC combined with GPC ) to the benefit of the analyst, but the analyst must always be keenly aware of which mode of operation is dominating when practicing such nonroutine analyses. 

Table 8.40 compares the main characteristics of WDXRF and EDXRF. Multidispersive XRF combines the benefits of the WDXRF technique for routine elemental analysis with the complete flexibility offered by EDXRF for nonroutine analysis. Clearly, modem XRF instrumentation is rather varied, ranging from simple benchtop EDXRF equipped with a low-power X-ray tube and high-resolution proportional counter for some key elements, to 4 kW simultaneous multichannel spectrometers with 28 fixed element channels for... 

The main disadvantages of SSNMR are related to the relatively high cost of the spectrometers and to the fact that the technique is nonroutine and requires a highly trained operator. Furthermore, because of the low sensitivity of the most interesting nuclei such as 13C or 1SN, a reasonable signal-to-noise ratio can only be achieved with a long acquisition time. Selective isotopic enrichment of certain sites in the molecule shortens the acquisition time by increasing the sensitivity however, the expense of the analysis increases dramatically. 

The main attention in this collection of scientific papers is on the recent theoretical and practical advances in polyblends and composites. This volume highlights the latest developments and trends in advanced polyblends and their structures. It presents new developments of advanced polyblends and respective tools to characterize and predict the material properties and behavior. The book provides important original and theoretical experimental results, which use nonroutine methodologies often unfamiliar to the usual readers. Chapters in this book also present novel applications of more familiar experimental techniques and analyses of composite problems which indicate the need for new experimental approaches presented. 

Although a number of innovative desorption ionization methods have been developed, none of these techniques has been commonly employed throughout the mass spectrometry community owing to the nonroutine nature of the experiments and the need for specialized instrumentation and sp>ecially trained per-... 

As techniques become more sophisticated, it becomes increasingly difficult to maintain each instrument in top condition. Despite this unavoidable difficulty, and despite the nonroutine nature of some measurements, it is important to know what can be achieved by present-day techniques. We hope that this article may serve to present an overview of modern techniques. 

If the diffraction data are of above-average quality, the full-profile method can easily allow quantification of crystalline phases well below the 1 wt% accuracy level. Advanced nonroutine application of the full-profile technique involve modelling of anisotropic Bragg peak broadening for the quantification of defective or disordered crystal phases. The... 

Gas chromatography provides data on the actual distribution of homologs in anionic surfactants, complementing the volumetric and colorimetric procedures which give a value for total anionic surfactant but do not indicate the compounds present. The sulfated and sulfonated materials which comprise most commercial anionics are not volatile, so GC analysis requires initial treatment to convert them to volatile products. The compatibility of GC with mass spectrometry makes the technique of great interest for nonroutine analysis of unknown products, an area where the application of HPLC is tedious indeed. A review by Rasmussen and McPherson gives additional perspective on the GC analysis of anionic surfactants (1). 

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