Bubble counts

Figure 2.4 Saturated boiling liquid temperature variations within thermal sublayer, and bubble counts departing from heating surface. (From Dougall and Lippert, 1967. Copyright 1967 by American Society of Mechanical Engineers, New York. Reprinted with permission.)...

The separate decompression tables of the French Navy, the U.S. Navy, and the Japanese Department of Labor, which are all based on the Haldane-ratio principle (ref. 408-410), require total decompression times for the test dive which are much shorter than those required by other military and commercial tables (Table 8.1). The first stop during decompression with either the FN, USN, or Japan tables occurred at a 10-ft depth, and the mean bubble counts ( S.E.M.) within the 0.27-ml agarose samples just prior to termination of this first (and only) stop were 127.25 9.39, 111.88 17.64, and 98.75 10.72, respectively. Of these three Haldane-ratio-principle tables, the FN table required the shortest total decompression time and the Japan table the longest time, so that the mean bubble number at the 10-ft depth was inversely related to the total decompression time. (In these three cases, the total decompression time essentially represented the sum of the initial... 

The shortest total decompression time specified by any of the schedules (11.04 min) was that of the Yount et al. schedule (ref. 135,414) for the standard dive. Nonetheless, the final number of bubbles produced by this particular schedule, 98.63 5.91 per agarose sample (0.27 ml), was less than that produced by any of the three tables (FN, USN, Japan) based on the Haldane-ratio principle (Table 8.1). In particular, the final bubble count produced by the FN schedule was markedly higher (P < 0.005), despite the fact that this schedule involved almost the same total decompression time, i.e., 12.00 min. The Yount et al. schedule has no stop during decompression, but instead initiates a slow and constant rate of decompression at about a 40-ft depth (ref. 135.414). The starting point for the slow decompression is, therefore, approximately 3.3 times deeper than with the tables (FN, USN, Japan) based on the... 

Usually this test is also applicable for set pressures up to 700 barg. In that case, the bubble count of 414 barg is used. 

The accuracy of determination of the average bubble parameters depends on the number of bubbles counted in each fraction (if the calculation is done by fractionation). 

Flowrate can be estimated through bubble counting. It is measured with a rotameter or a differential monometer. The rotameter is... 

Comparisons of continuous distributions to discrete experimental data must accommodate the size ranges or bins selected by the investigators for the bubble count. The measured probability of bubbles at a given size, V, is actually the fraction of those measured that falls in a range, say v, to Vj. 

The C02 is accompanied by radon, which is difficult to separate. The C02 is therefore often stored before counting its 14C activity. A small amount of radon is in the bubble fraction larger amounts of radon are in the purged extractions. The C02 is purified before counting by a series of freezing and unfreezing steps. 

Much of this work was carried out using a special distilling column called a bubble-plate column (Fig. 141). Each plate really does act like a distilling flask with a very efficient column, and one distillation is really carried out on one physical plate. To calculate the number of plates (separation steps, or distillations) for a bubble-plate column, you just count them ... 

When the frequency of bubble formation is very low (<200 bubbles per minute), the bubbles can be visually counted without the aid of any instrument. When the frequency is higher than this, other methods have to be employed. 

The process calls for feeding ethylene and mixed butylenes to the bottom of a reactor. The mixed butylenes consist of both butene-1 and butene-2. (Refer to Figure 1—10 to refresh your memory about the difference.) A slurry of rhenium-based catalyst is introduced at the top. As the ethylene and butylenes bubble past the catalyst, the ethylene and butene-2 will react to form propylene (the carbon count is right). Simultaneously, as the butene-2 is consumed, butene-1 isomerizes to create more. 

K diebromate soln in it), serving to count the number of bubbles of air entering thru stopcock Rg and to retain any gas or vapor which might adversely affect the analysis B — Round bottom flask, called "un ballon de saponification ... 

The hydrogen chloride is introduced at such a rate that the bubbles form a little faster than they can be counted. 

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