Monitoring nondestructive probes

NMR is an incredibly versatile tool that can be used for a wide array of applications, including determination of molecular structure, monitoring of molecular dynamics, chemical analysis, and imaging. NMR has found broad application in the food science and food processing areas (Belton et al., 1993, 1995, 1999 Colquhoun and Goodfellow, 1994 Eads, 1999 Gil et al., 1996 Hills, 1998 O Brien, 1992 Schmidt et al., 1996 Webb et al., 1995, 2001). The ability of NMR to quantify food properties and their spatiotemporal variation in a nondestructive, noninvasive manner is especially useful. In turn, these properties can then be related to the safety, stability, and quality of a food (Eads, 1999). Because food materials are transparent to the radio frequency electromagnetic radiation required in an NMR experiment, NMR can be used to probe virtually any type of food sample, from liquids, such as beverages, oils, and broth, to semisolids, such as cheese, mayonnaise, and bread, to solids, such as flour, powdered drink mixes, and potato chips. 

LIF methods can be applied in-line, at-line and on-line for real-time monitoring as discussed throughout this chapter. In-line or in situ intrinsic LIF is by far more prevalent in real-time applications such as PAT as it is nondestructive and simple to deploy along with attractive analytical merits. In-line application can be accomplished by direct insertion in situ probes or flow cells. This type of monitoring is utilized for realtime analyte quantification monitoring and detection of process endpoints and faults. 

In the distant past, measurements of the attenuation of the (3 spectrum from a newly discovered isotope were used to identify the energy of the (3 decay. Recently, the attenuation of strong sources has been used to monitor the thickness of materials during manufacturing processes. Notice that the monitoring can be continuous, nondestructive, and a physical probe does not need to touch the material being measured. 

The mechanical properties of the nanocomposites strongly depend on their structure, orientation of the filler, phase separation, and processing conditions. Hence, there is a need for in situ nondestructive characterization technique to probe the internal stress in nanocomposite structures. The shortcomings of many conventional techniques such as low resolution, destructive measurements, complex modeling and applicability to only certain class of materials are overcome by using pRS owing to the sensitivity and nondestructive measurement for monitoring internal stress in various materials [59]. 

Y. Ozaki, A. Mizuno, T. Hayashi, K. Tashibu, S. Maraishi, and K. Kawauchi, Nondestructive and Noninvasive Monitoring of Deoxyhemoglobin in the Vein by Use of a Near-Infrared Reflectance Spectrometer with a Fiber-Optic Probe, Appl. Spectrosc., 46(1), 180 (1992). 

L.G. Cooper, Sensing probes and instruments for electrochemical and electrical resistance corrosion monitoring, in G.C. Moran, P. Labin (Eds.), Corrosion Monitoring in Industrial Plants Using Nondestructive Testing and Electrochemical Methods, ASTM STP 908ASTM International, West Conshohocken, PA, 1986. 

In the present study, we used this ATR FT-IR approach with tribological experiments to probe the lubif cant layer between sliding surfaces by measuring ATR spectra from the underside of a thin metallic film. In this way, the metal surface/lubricant interface can be continuously monitored, in situ, and in a nondestructive manner during a complete tribological sliding experiment. 

Many polymers and most PMC show no or only comparatively low electrical conductivity, which limits application of electromagnetic test methods. One of the main exceptions is CFRP. The continuous network of carbon fibers in CFRP allows for electrical resistance measurements, eg, based on the four-probe method. Electrical potential (101) or resistance methods are used in fracture mechanics to detect delaminations (102) and to monitor damage in CFRP (103). Whether the application of electrodes is nondestructive depends on the intended use. 

NDE technology denotes application of a diverse array of nondestructive processes to monitor, probe, and measure material response. The measured response is related to a desired material property or test object attribute by interpretation. The main NDE methods are... 

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