Nondestructive analytical techniques

Nondestructive radiation techniques can be used, whereby the sample is probed as it is being produced or delivered. However, the sample material is not always the appropriate shape or size, and therefore has to be cut, melted, pressed or milled. These handling procedures introduce similar problems to those mentioned before, including that of sample homogeneity. This problem arises from the fact that, in practice, only small portions of the material can be irradiated. Typical nondestructive analytical techniques are XRF, NAA and PIXE microdestructive methods are arc and spark source techniques, glow discharge and various laser ablation/desorption-based methods. On the other hand, direct solid sampling techniques are also not without problems. Most suffer from matrix effects. There are several methods in use to correct for or overcome matrix effects ... 

Also the consumer s needs—exactly like the manufacturer s ones— require rapid, effective, low-cost, and nondestructive analytical techniques, in order to accomplish a widespread control and achieve broader quality assurances saving the costs. 

Photoacoustic spectroscopy (PAS) is a nondestructive analytical technique in which light entering the photoacoustic cell passes through undetected if the sample is nonabsorbing, but heats up and expands the gas in the cell if the light is absorbed. This expansion makes an audible sound whenever absorption occurs and is detected by a microphone. The SNR may increase with the sample surface area. PAS determinations were carried out for hfac chelates of Sc, Y and the rare earth Ce, Pr, Nd, Eu and Er. ... 

Near-infrared spectroscopy (NIR), which is a nondestructive analytical technique, has been employed for the simultaneous prediction of the concentrations of several substrates, products, and constituents in the mixture sampled from fermentation process. In this chapter, applications of NIR to monitoring of the various fermentation processes are introduced. The fermentation processes mentioned here are wine, beer, Japanese sake, miso (soybean paste), soy sauce, rice vinegar, alcohol, lactic acid, glutamic acid, mushroom, enzymatic saccharification, biosurfactant, penicillin, and compost. The analysis of molasses, which is a raw material of fermentation, with NIR is also introduced. These studies indicate that NIR is a useful method for monitoring and control of fermentation process. 

Using synchrotron transmission FTIR microspectroscopy as a rapid, direct and nondestructive analytical technique to reveal molecular microstructural-chemical features within tissue in grain barley. /. Agric. Food Chem., 52 (6),... 

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