EMPA method

EMPA-Methode (6) cystine with sulphite, colori- peroxide, reducing agents ... 

The X-ray emission process followii the excitation is the same in all three cases, as it is also for the electron-induced X-ray emission methods (EDS and EMPA) described in Chapter 3. The electron core hole produced by the excitation is filled by an electron falling from a shallower level, the excess energy produced being released as an emitted X ray with a wavelength characteristic of the atomic energy levels involved. Thus elemental identification is provided and quantification can be obtained from intensities. The practical differences between the techniques come from the consequences of using the different excitation sources. 

These same six samples were also analyszed by inductively coupled plasma-mass spectrometry (ICP-MS) to determine if the same element patterns detected in the EMPA analysis could be observed with a less labor intensive method. ICP-MS works in a similar manner as TIMS, expect the sample is dissolved and injected into a plasma flame in order to atomize and ionize the sample. Isotopes ratios can be determined in this manner, but generally the precision is less than with TIMS. 

Finally, the same authors reported the incorporation of electrokinetic injection into their method (31). Little interference was observed in the separation of MPA, EMPA, IMPA, and PMPA in seven different environmental matrices. Limits of detection were reduced to 1—2 xg/L for water samples, which represented an improvement of two orders of magnitude over their previous work using pressure injection. However, a sample cleanup step was necessary to reduce the conductivity of the sample to be compatible with electrokinetic injection. The samples were passed through three pretreatment cartridges arranged in series to remove sulfate, chloride, and cations, respectively. 

Tsuchihashi et al. (1998) have developed a method for identification of VX metabolites in serum collected from a victim of the Osaka VX incident. In the serum sample, both EMPA and 2-(diisopropylamino-ethyl)methyl sulfide were detected. The techniques using GC-MS and GC-MS-MS were applicable to biological samples such as serum. These results provided the first documented identification of the specific metabolites of VX in victims serum and clarified a part of the metabolic pathway of VX in the human body. In addition, methods have been developed for measuring the VX-inhibited AChE hydrolytic product EMPA (Noort et al, 1998 2002). 

All of these anchorage systems, however, must be fixed to the base element with screws or dowels. A method developed at the Swiss Federal Laboratories for Materials Testing and Research (Empa) produces a decrease in the prestressing force at the strip end (see Fig. 4.11) and therefore does not require any permanent anchorages and steel pieces (Czaderski and Motavalli 2007, Aram et al. 2008b, Motavalli et al. 2010). 

Kiibler, J. (1999) Fracture toughness of ceramics using the SEVNB method Roimd Robin, ESIS Document D2-99, EMPA. 

A biocide eannot be advertised as having certain effects unless these elaims have been supported by testing. Various standard and non-standard test methods can be used to evaluate how effective a specific biocide is at protecting materials and users. They inelude agar plate tests, direct contamination of a test specimen and in-service tests, such as soil burial. Different test methods may be preferred for different biocide types. ISO 846, ISO 16869, ASTM G-2I and G-22, ASTM E-I428, DIN 53793, JIS Z 2911, NF-X4I-5I4 and EMPA 223/23 are some of the standards used. Articles discussing the available tests in an introductory fashion are available in the books of papers presented at recent Rapra Addcon World conferenees (www.polymer-books.com). 

Left all methods (norms and in-house) right according to norms of Table 6.28 only. After Affolter et al. [47]. Reproduced by permission of M. Schmid, EMPA, St. Gallen. 

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