SPRITE element

Fig. 4 shows the application of a 1-D SPRITE technique to map the distribution of coke within a model fixed bed. In this particular example two layers of coked HZSM-5 were separated by a layer of fresh HZSM-5 (Fig. 4a).21 Each layer was 3.3 cm in length. Fig. 4b shows the profile of coke within the sample recorded by 1H SPRITE imaging these data were recorded in 15 min. The coke had a EEC ratio of 0.5, as determined by elemental analysis and the T2 of the sample was 65 ps—far shorter than could be studied using conventional spin-echo methods. It is worth emphasizing that SPRITE is mapping the coke directly in this experiment, although it should be noted that since it is imaging the H signal, as the coke becomes more graphitic in nature the amount of available H species that can be imaged will...

Sigma-blade mixer, in bar soap manufacture, 22 751 Signaling smokes, 5 827, 830 Signal processing in the element (SPRITE), 29 162-163... 

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