Non-destructive assay

AR532 5.11 Non-destructive assay of special nuclear material contained in scrap and waste (Rev.l,... 

An On-line alpha monitor has been developed for assaying Pu in trace levels in process streams. This monitor has also been qualified for uranium streams.The neutron collar for the measurement of Pu in larger concentrations has been tested in dynamic mode, and is ready for deployment. Methods have been developed for the non-destructive assay of Pu in glove box waste, and a system has been made operational for measurements on waste generated at IGC AR. An optical fibre adaption to a commercial fluoiimeter has been set up to demonstrate the... 

NDA Non Destructive Assay. A number of techniques used for measuring radioactive waste, most of them being based on detecting gamma-rays and/or neutrons. 

At PicArsn, both thermal and fast NAA were compared for non-destructive gross element assay in selected materials used in ammo (Ref 14), specifically A1 in aluminized high expls (eg, Minols), Cl in AP and Mn in manganese dioxide (as used in pyrotechnic flare compns). 

Non-destructive analysis is especially valuable in an on line situation. X-ray fluorescence has above all become of major importance for the analysis of inorganic process streams. Cement production is an example of the successful application of this technique. The X-ray analyser can be used for the simultaneous assay of the various feedstocks (iron ore, clay and limestone) for Fe203, A1203, Si02 and CaO. In turn the signals from the analyser are used to control the feedstock supplies to the blending mill and to maintain an optimum product composition. 

The aromatic rings in the protein absorb ultraviolet light at an absorbance maximum of 280 nm, whereas the peptide bonds absorb at around 205 nm. The unique absorbance property of proteins could be used to estimate the level of proteins. These methods are fairly accurate with the ranges from 20 p,g to 3 mg for absorbance at 280 nm, as compared with 1 to 100 p,g for 205 nm. The assay is non-destructive as the protein in most cases is not consumed and can be recovered. Secondary, tertiary and quaternary structures all affect absorbance therefore, factors such as pH, ionic strength, etc can alter the absorbance spectrum. This assay depends on the presence of a mino acids which absorb UV light (mainly tryptophan, but to a lesser extent also tyrosine). Small peptides that do not contain such a mino acids cannot be measured easily by UV. 

Wakamoto, Y.C., Umehara, S., Matsumura, K., Inoue, I.,Yasuda, K., Development of non-destructive, non-contact single-cell based differential cell assay using on-chip microcultivation and optical tweezers. Sensors Actuators B 2003, 96, 693-700. 

Aldridge and coworkers described a NIRS method for non-destructive identification of blister-packaged tablets. The NIR method drastically reduced the assay time required by the previous TLC method. The TLC method required a full day to analyze 40 tablets, compared with the NIR method, which analyzed 10 tablets in 7 min. 

Drennen and Lodder reported a non-destructive NIRS method to monitor the decomposition of aspirin. In contrast to the multi step HPLC assay for salicylic acid and the USP identity tests for aspirin, the NIR method involved a 90s scan of individual intact aspirin tablets. The workers correlated changes... 

Bickham, J.W. (1994) Genotoxic responses in blood detected by cytogenetic and cytometric assays. In Non-destructive Biomarkers in Vertebrates, Fossi, M.C. and Leonzio, C. (eds), pp. 37-62. Lewis Publishers, Boca Raton, FL. 

AR537 5.21 Non-destructive uranium-235 enrichment assay by gamma ray spectrometry (Draft SG 044-4,... 

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. 

Monfre, S.L. and F.A. DeThomas, Non-destructive pharmaceutical tablet assay by near-infrared spectroscopy. Near infrared spectroscopy Bridging the gap between data analysis and NIR applications, ed. K.I. Hildrum. Ellis-Horwood Chichester, UK (1992). 

The assay of enzyme induction at the mRNA level is much easier to perform than the chemical assay of each individual enzyme and the response to a physiological event is intrinsically faster to detect. Moreover, mRNA is often more stable under cell extract preparation conditions than enzymes, if destruction by RNAses can be prevented. For analysing a number of different enzymes in parallel, only one sample preparation procedure is necessary, which produces a crude RNA extract, and only in the final step the different DNA or RNA probes are used for detection of specific enzyme RNAs. Recently, the detection of RNA is further facilitated by ready-to-use RNA isolation kits, non-radioactive DNA or RNA probes and the dot-blot and slot-blot techniques, respectively, [51,52]. 

As mentioned in the Section 1, physico-chemical methodology for quantitative analysis of plant hormone focuses primarily on GC-SIM, although HPLC with selective fluorescence detection continues to be used for lAA analysis in some laboratories. Procedures, such as the 2-methylindolo-a-pyrone assay for lAA analysis [82], are now rarely utilised. With the exception of ethylene quantification [2] there is little use of non-MS-based GC detection techniques, despite the fact that selective analysis at the picogram level is achieved for ABA with an electron capture detector [83], and lAA and cytokinins with a nitrogen phosphorus detector [84,85]. The reason for the demise of these GC procedures is that the detectors are destructive and this precludes the reliable recovery of labelled internal standards for radioassay and isotopic dilution analysis. The usual compromise was to take two aliquots of the purified samples, one for GC analysis and the other for the determination of radioactivity. The accuracy of this approach is dependent upon the questionable assumption that the radioactivity in the purified sample is associated exclusively with the compound under study. In an attempt to circumvent this problem, a double standard isotope dilution procedure was devised for the quantitative analysis of lAA in which one internal standard was used to correct for losses during sample preparation and a second for GC quantification [86]. This procedure was used in several... 

As regards the redox potential, it is quite predictable that iron in wine is not totally in ion form. Part of the iron is involved in soluble complexes with organic acids, especially citric acid. Ferric iron is much more likely to form complexes than ferrous iron. Ferric and ferrous iron, expressed as Fe and Fe , constitute total iron, in both ions and complexes, i.e. non-reactive forms. A total iron assay therefore requires the complete destruction of these complexes by acidification. The use of potassium thiocyanate, a specific reagent for ferric... 

There are several reagents that can be used for qualitative and quantitative assay of the separated lipids. Apart from these there are specific spray reagents available to characterize individual lipid groups. Detection methods can be classified mainly into two categories, the nondestructive methods and the destructive methods, and these can be further classified into specific and non-specific detection methods. It is... 

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