Dump criteria

Dump criteria is the standard taken in judging the momait when the mixing is deemed as complete. 

Most of the systems that have been installed concentrate on the materials handling as much as on control of the mixing process itself. Early systems were controlled using punched cards which gave instructions on weighing and addition of raw materials and on dump criteria. Basically, these systems reduced the chance of human error. More recent systems do all of the above, but also include a programmable controller. One important advantage of these is that they can provide a printed record of each batch. Details of the... 

Other investigators have also dealt with the 1-D question. Ruthven 78) has used the Fischer criterion in an assessment of applicability of the 1-D model for BOD. McQuivey and Keefer 62) note that about 150 miles may be required in a particular stretch of the lower Mississippi River for 1-D conditions to be met after a dye dump. 

In the 1970s, high levels of mercury were found in fish taken from Lake St. Clair, which lies between the United States and Canada. Chlorine plants that dumped depleted brine into the waterways were among the contributors. Before these incidents, many assumed that the very low solubility of mercury meant that it would have great difficulty entering the food chain. However, it can be assimilated by certain water-borne bacteria and converted into methyl mercury and its compounds. Eventually, mercury appears in the fatty tissue of fish, concentrated more than 1,000 times. It continues to concentrate as it works its way through the food chain. In a recent development, the EPA adopted a new criterion for water quality based on the level found in fish. The level of 0.3 ppm is equivalent to 7ngL in the water, a 7-fold reduction from the previous standard. This is said to be the first standard based on accumulation of a substance in marine life rather than on its concentration in the water [23]. 

Figure 4.14 shows a screen dump of an isothermal gas chromatographic simulation from a commercial gas chromatographic optimization program. The Temperature, Pressure, and Column tabs in the display permit the user to set elution conditions, including multiramp temperature and pressure programming, which were not exercised for this example. The Auto-Optimize tab carries out a minimum-resolution-oriented optimization calculation, which determines a set of conditions that lie within specified limits and meet the minimum resolution criterion. 

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