Methods non-destructive analytical

Multilayered structures play an important role in the production of, e.g., biomaterials, catalysts, corrosion protectors, detectors/diodes, gas and humidity sensors, integral circuits, optical parts, solar cells, and wear protection materials. One of the most sophisticated developments is a head-up-display (HUD) for cars, consisting of a polycarbonate substrate and a series of the layers Cr (25 nm), A1 (150 nm), SiO, (55 nm), TiO, (31 nm), and SiO, (8 nm). Such systems should be characterized by non-destructive analytical methods. 

The analysis was performed by XRF method with SR. SRXRF is an instrumental, multielemental, non-destructive analytical method using synchrotron radiation as primary excitation source. The fluorescence radiation was measured on the XRF beam-line of VEPP-3 (E=2 GeV, 1=100 mA), Institute of Nuclear Physics, Novosibirsk, Russia. For quality control were used international reference standards. 

In the case of non-destructive analytical methods the sintered object is subjected to an analysis which does not cause any damage to the sample. Until recently these techniques, like X-ray (diffraction) analysis, ultrasonic waves and CT scans, were only applied in the medical... 

Typically, PIXE measurements are performed in a vacuum of around 10 Pa, although they can be performed in air with some limitations. Ion currents needed are t5q)ically a few nanoamperes and current is normally not a limiting factor in applying the technique with a particle accelerator. This beam current also normally leads to no signifrcant damage to samples in the process of analysis, offering a non-destructive analytical method sensitive to trace element concentration levels. 

Peptide-tethered platinum(ll) complexes have been prepared using solid-supported techniques and gel-phase Pt-195 NMR spectroscopy used as a non-destructive analytical method for on-support analysis. This... 

Though the goal of nanoencapsulating OPAA into a stable, active, and reusable material was accomplished, more research is still needed. For example, an alternative, non-destructive, analytical method for determining OPAA activity would be helpful to reduce assay time and not be limited by concentration effects. Additionally, a range of solvents would test the limits and stability of the nanoencapsulated OPAA. Other operating parameters, such as pH and temperature, also merit further study. 

Raith, A., Hutton, R. C., Abell, I. D., and Crighton, J. (1995). Non-destructive sampling method of metals and alloys for laser ablation-inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectroscopy 10 591-594. 

Spectroscopic methods can provide fast, non-destructive analytical measurements that can replace conventional analytical methods in many cases. The non-destructive nature of optical measurements makes them very attractive for stability testing. In the future, spectroscopic methods will be increasingly used for pharmaceutical stability analysis. This chapter will focus on quantitative analysis of pharmaceutical products. The second section of the chapter will provide an overview of basic vibrational spectroscopy and modern spectroscopic technology. The third section of this chapter is an introduction to multivariate analysis (MVA) and chemometrics. MVA is essential for the quantitative analysis of NIR and in many cases Raman spectral data. Growth in MVA has been aided by the availability of high quality software and powerful personal computers. Section 11.4 is a review of the qualification of NIR and Raman spectrometers. The criteria for NIR and Raman equipment qualification are described in USP chapters <1119> and < 1120>. The relevant highlights of the new USP chapter on analytical instrument qualification <1058> are also covered. Section 11.5 is a discussion of method validation for quantitative analytical methods based on multivariate statistics. Based on the USP chapter for NIR <1119>, the discussion of method validation for chemometric-based methods is also appropriate for Raman spectroscopy. The criteria for these MVA-based methods are the same as traditional analytical methods accuracy, precision, linearity, specificity, and robustness however, the ways they are described and evaluated can be different. 

It is very important to note that the metallic impurities in CNTs are the important factor in inducing significant toxic responses. Therefore, a quantitative measurement of the concentration of metal impurities in CNTs is key, although this is very difficult. Recently, neutron activation analysis (NAA) technique as a non-destructive standard method has been used to quantitatively analyse the metal impurities in CNTs, and ICP-MS is regarded as a practical analytical method. In the absence of a true reference material for CNTs, the NAA method can provide the best estimate of the true value of metallic impurities in CNTs, while ICP-MS is a desktop instrumental... 

In-depth distribution analysis of chemical composition is a special case of local microanalysis, for which the third (axial) dimension is of primary interest. In principle, this task requires the compositional analysis of thin sections (in the ultimate dimension of monatomic layers) defined on a depth scale. It can be obtained either by non-destructive or destructive techniques. Non-destructive techniques are based on an analytical signal parameter (e.g. intensity and/or energy), which has a weU-deflned dependence on its depth of origin. For example, in electron spectroscopy, non-destructive profiling methods are based on either the energy or the emission angle dependence of the mean escape depth of the emitted electrons e.g. ARXPS). Confocal microscopy... 

NIR spectroscopy has become an analytical tool frequently called upon in many production processes. Its use in polymer processing applications such as polymer extrusion [83] increases greatly product quality. The applications of non-destructive NIR methods to synthetic polymer studies have been reviewed [131-133]. Typical reported applications include process and pilot monitoring [134], realtime analysis of thermoplastic melt processes [129, 135], insoluble cross-linked systems [136], polymer flakes, fluffs and film. NIRA has controlled production in dyeing of textured PA6 carpet yarns with... 

By measuring the energy of the characteristic X-rays emitted, the elemental composition of the sample can be determined. PIXE is also a non-destructive analytical technique which can be used to image the distribution of major, minor, and trace constituents in various samples. The method is sensitive to... 

Oxides (Ln Oj), fluorides (LnF ), sulfides (Ln S, LnS), sulfofluorides (LnSF) of lanthanides are bases of different functional materials. Analytical control of such materials must include non-destructive methods for the identification of compound s chemical forms and quantitative detenuination methods which does not require analytical standards. The main difficulties of this analysis by chemical methods are that it is necessary to transform weakly soluble samples in solution. 

It must be stressed, however, that the whole object may be the analytical sample, e.g. a specimen of moon-rock. Ideally this sample would be analysed by non-destructive methods. Occasionally the bulk material may be homogeneous (some water samples) and then only one increment may be needed to determine the properties of the bulk. This increment should be of suitable size to provide samples for replicate analyses. 

All the analytical methods mentioned to separate, identify, and quantify chlorophylls and derivatives consume time, money, and samples. As alternatives, industries have been employing non-destructive methods for surface color measurements that are not only indirectly related to chlorophyll content, but may also estimate the pigments directly in tissues, leaving the sample intact and enabling serial analyses in a relatively short time. Eood color affects consumer acceptance and is an important criterion for quality control. Color vision is a complex phenomenon that depends on both the total content and number of pigments and also on absorption, reflectance and emission spectra of each compound present. 

The use of differential UV spectroscopy is a facile analytical tool, providing a rapid, non-destructive method for determining the course and extent of degradation of PC films during accelerated or natural weathering. 

There is constant development and change in the techniques and methods of analytical chemistry. Better instrument design and a fuller understanding of the mechanics of analytical processes enable steady improvements to be made in sensitivity, precision, and accuracy. These same changes contribute to more economic analysis as they frequently lead to the elimination of time-consuming separation steps. The ultimate development in this direction is a non-destructive method, which not only saves time but leaves the sample unchanged for further examination or processing. 

ABSTRACT The aim of this study was to test portable infrared spectroscopy for non-destructive analysis of ancient construction mortar. Mortar samples from the House of the Vestals, in Pompeii, Italy, were initially examined with traditional analytical techniques, including X-ray fluorescence, X-ray diffraction and thin section analysis. These techniques were used to establish mineralogical and chemical profiles of the samples and to verify the results of experimental field methods. Results showed the lime-based binder was composed of calcite, and the volcanic sand aggregate contained clinopyroxene, plagioclase, sanidine and olivine crystals. 

The aspects which relate to the homogeneity of the sample have to be considered in the context of the nature of the analytical process. Also the nature of the analytical process is determined by the characteristics of the sample to be analysed. Hence the two groups of analytical methods, destructive and non-destructive, should be considered separately. Although both groups have wide applicability, the analytical chemist has a tendency to prefer the non-destructive methods. Since such methods act directly upon the sample, they have the advantage of partly—and with some precautions, totally—eliminating the risk of contamination of the sample. 

The choice of one or other of the methods depends on the nature of the sample. Generally, the non-destructive methods are applied to samples with relatively simple composition. However, for more complex samples or when the determination of major and minor components is required, preliminary separation of the components and concentration of the minor or trace components are necessary, before the actual determination may be performed. It follows therefore, that the analytical chemist must resort in many cases, willingly or not, to destructive methods of analysis. 

This chapter reviews the various methods used to identify and characterize iron oxides. Most of these are non-destructive, i. e. the oxide remains unaltered while being examined. These methods involve spectroscopy, diffractometry, magnetometry and microscopy. Other methods, such as dissolution and thermal analysis destroy the sample being examined. Only the principle of each method is given here. The main weight is put on the information about Fe oxides which can be extracted from the analytical results obtained by the different techniques together with references to relevant studies. A detailed description of each technique can be found in the appropriate texts listed in each section. 

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