Detection methods for

Because these pipes are key components used for airplanes, their ultrasonic testing quality must be guranteed. Therefore, the author has conducted studies about the flaw detection methods for coarse-grained TC4P extrusion pipes. 

Luminescence has been used in conjunction with flow cells to detect electro-generated intennediates downstream of the electrode. The teclmique lends itself especially to the investigation of photoelectrochemical processes, since it can yield mfonnation about excited states of reactive species and their lifetimes. It has become an attractive detection method for various organic and inorganic compounds, and highly sensitive assays for several clinically important analytes such as oxalate, NADH, amino acids and various aliphatic and cyclic amines have been developed. It has also found use in microelectrode fundamental studies in low-dielectric-constant organic solvents. 

Biosensors (qv) and DNA probes ate relatively new to the field of diagnostic reagents. Additionally, a neat-infrared (nit) monitoring method (see Infrared TECHNOLOGY AND RAMAN SPECTROSCOPY), a teagenfless, noninvasive system, is under investigation. However, prospects for a nit detection method for glucose and other analytes ate uncertain. 

Fig. 5. Detection methods for glucose enzyme electrode based on (a) oxygen, (b) hydrogen peroxide, and (c) a mediator. See text.

Plasma atomic emission spectrometry is also employed as a detection method for gc (see Plasma technology). By monitoring selected emission lines a kind of selective detection based on elemental composition can be achieved (see Spectroscopy). 

Shape of vessel (ciihic or elongated vessel) Detection method for triggering a shutdown... 

G. A. Codd, T. M. Jefferies, C. W. Keevil and E. Potter, Detection Methods for Cyanobacterial... 

C. Edwards, L.A. Lawton and G. A. Codd, in Detection Methods for Cyanobacterial Toxins, ed. 

M. Cai eii and A. Mangia, Multidimensional detection methods for sepai ations and their application in food analysis . Trends Anal. Chem. 15 538-550 (1996). 

Note When combined with thin-layer chromatographic separation the reagent provides a specific detection method for nitrate and nitrite. The color development is often completed within a few minutes on silica gel plates. In the absence of ammonia vapor traces of oxides of nitrogen in the laboratory atmosphere can slowly cause the background to become reddish-brown. The simultaneous presence of the following ions in the chromatogram zones interferes with the detection of nitrate/nitrite I , 10J, IO4, MoO and H2PO2. 

Some Formal Considerations. As with most natural toxins, detection methods for the saxitoxins are an essential prerequisite for most studies of them, as well as for monitoring programs to ensure the safety of food products that may contain them. Furthermore, the degree of success of such efforts is dependant on the characteristics of the detection method used. Detection of the saxitoxins is particularly challenging because of the large number of different but related compounds that must be dealt with, the low levels that must be detected, and their chemical characteristics. Given these factors it is useful to dwell briefly on some underlying principles. 

Some Chemical Considerations Relevant to the Mouse Bioassay. Net toxicity, determined by mouse bioassay, has served as a traditional measure of toxin quantity and, despite the development of HPLC and other detection methods for the saxi-toxins, continues to be used. In this assay, as in most others, the molar specific potencies of the various saxitoxins differ, thus, net toxicity of a toxin sample with an undefined mixture of the saxitoxins can provide only a rough approximation of the net molar concentration. Still, to the extent that limits can be placed on variation in toxin composition, the mouse assay can in principle provide useful data on trends in net toxin concentration. However, the somewhat protean chemistry of the saxitoxins makes it difficult to define conditions under which the composition of a mixture of toxins will remain constant thus, attaining a reproducible level of mouse bioassay toxicity is difficult. It is therefore useful to review briefly some of the chemical factors that should be considered when employing the mouse bioassay for the saxitoxins or when interpreting results. Similar concepts will apply to other assays. 

We have described the use of FTMS as a detection method for laser desorption of molecular adsorbates from metal surfaces. FTMS provides several important characteristics for these experiments. 

Separation and detection methods The common methods used to separate the Cr(III)/(VI) species are solvent extraction, chromatography and coprecipitation. In case of Cr(VI) from welding fumes trapped on a filter, a suitable leaching of the Cr(VI) from the sample matrix is needed, without reducing the Cr(VI) species. The most used detection methods for chromium are graphite furnace AAS, chemiluminescence, electrochemical methods, ICP-MS, thermal ionization isotope dilution mass spectrometry and spectrophotometry (Vercoutere and Cornelis 1995)- The separation of the two species is the most delicate part of the procedure. 

III. REGULATION OF DETECTION METHODS FOR FOOD ALLERGENIC INGREDIENTS... 

Therefore, we developed detection methods for determining the presence of proteins on the level of a few micrograms per milliliter or gram of food based on the definition of a trace amount. 

TABLE 4.7 Japanese guideline criteria for validation protocol of quantitative detection methods for food allergenic ingredients"... 

D. Detection methods for specific allergenic ingredients (Notification No. 1106001, 2002)... 

G. Development of detection methods for subspecific allergenic ingredients... 

A sensitive qualitative detection method for walnut using PCR was also developed (Yano et ah, 2007). For detection of walnuts with high specificity, the primer pair was designed based on walnut matK genes. Trace amounts of walnuts in commercial food products can be qualitatively detected using this method. 

Tanabe, S., Hase, M., Yano, T., Sato, M., Pujimura, T., and Akiyama, H. (2007). Real-time quantitative PCR detection method for pork, chicken, beef, mutton, and horseflesh in foods. Biosci. Biotechnol. Biochem. 71, 3131-3135. 

Watanabe, T., Akiyama, H., Yamakawa, H., lijima, K., Yamazaki, F., Matsumoto, T., Futo, S., Arakawa, F., Watai, M., and Maitani, T. (2006). A specific qualitative detection method for peanut (Arachis hypogaea) in foods using polymerase chain reaction. /. Food Biochem. 30, 215-233. 

Three types of detection methods for TLC may be distinguished, namely physical, microchemical and biological-physiological. The more common detection methods for polymer additives in TLC are given in Figure 4.8. Detection is an off-line process, thus several detection techniques may be used one after the other. 

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