Techniques, primary

Electron Microprobe A.na.Iysis, Electron microprobe analysis (ema) is a technique based on x-ray fluorescence from atoms in the near-surface region of a material stimulated by a focused beam of high energy electrons (7—9,30). Essentially, this method is based on electron-induced x-ray emission as opposed to x-ray-induced x-ray emission, which forms the basis of conventional x-ray fluorescence (xrf) spectroscopy (31). The microprobe form of this x-ray fluorescence spectroscopy was first developed by Castaing in 1951 (32), and today is a mature technique. Primary beam electrons with energies of 10—30 keV are used and sample the material to a depth on the order of 1 pm. X-rays from all elements with the exception of H, He, and Li can be detected. 

Technique Primary probe Elemental range Type of information Depth of information Lateral resolution Sensitivity (at. %) Ease of quantification Insulator analysis Destructive UHV environment... 

Differences in integration time scales may also affect our perception of key derived parameters such as the ThE ratio (Cochran et al. 2000). This ratio (see above) compares the POC flux derived from water column " Th profiles (and thus integrating into the past) with present primary production. As classically measured using incubation techniques, primary production is an instantaneous measurement representing the phytoplankton community as sampled at a single time. Under bloom conditions, the export of POC may lag the production of fresh organic matter and ThE ratios calculated late in a bloom may be overestimates. 

Parameters for the optimization of programmed analyses in various chromatographic techniques. Primary parameters may be used to optimize the program parameters (initial and final conditions, slope and shape). Secondary parameters may be used to optimize the selectivity. 

Casting and Powder Metallurgical Techniques (Primary Shaping)... 

Transmission electron microscopy (TEM) has higher resolution than SEM as it uses high-energy electron beam. In this technique, primary electrons transmitted through the specimen are detected, which gives morphological and... 

End-of-pipe technique a technique that reduces final emissions or consumptions by some additional process but does not change the fundamental operation of the core process. Synon5mis "secondary technique", "abatement technique". Antonyms "process-integrated technique", "primary technique" (a technique that in some way changes the way in which the core process operates thereby reducing raw emissions or consumptions)... 

Unscheduled DNA synthesis, alkaline elution techniques Primary DNA damage and detected in cultured mammalian cells 43-45 Becoming routine in many laboratories. 

Technique Primary excitation Analysed emission Infor- mation E>eptli rang e Lateral resolution Mapr info. Quanti- fication GKarging Destruct- iveness S... 

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