Data collection yield monitors

The data most frequentiy collected and reported in catalyst performance evaluations are activity or turnover number, selectivity to the desired product(s), overall yield, catalyst life, and the identities and yields of by-products produced. These data are used to further catalyst or process development research efforts, to monitor catalyst manufacture, and to provide quaUty assurance information to catalyst users. 

Surveillance programmes also exist in occupational settings. In this case, it may be possible to follow reproductive histories (including menstrual cycles) or semen evaluations to monitor reproductive effects of exposure. With adequate exposure information, these could yield very useful data for risk assessment. Reproductive histories are easier and less costly to collect than semen evaluations. Semen studies also may have limited response rates, thus reducing their representativeness. It is important to reassure workers that the data they provide for such programmes remain confidential and will not affect their employment status (Samuels, 1988 Lemasters, 1993 Lindbohm, 1999). 

A three year study monitoring acid precipitation across Central Indiana has just been completed by the authors ( ) and the local International Rotary Club who donated the manpower for sample collection. Over 3000 individual samples were collected during approximately 300 individual precipitation events. Using acceptible analytical and statistical protocol, the samples were characterized by meteorological, physical, and trace chemical composition data to determine possible sources of the acidity. The study yielded pertinent environmental data that set the parameters for this work. 

Slot sizes of the screens are chosen to maximize well yield so that reliable water samples and water-level drawdown data can be collected during specific-capacity and other field tests. To accomplish this, sieve analyses can be performed on split-spoon samples from the interval to be monitored. A grain-size distribution curve can be field plotted and analyzed to establish the screen slot size and the size of the gravel pack. For wells installed in competent bedrock, it may be wisest not to install a screen but to leave the hole open for maximum yield. In these cases, a surface casing is installed to prevent the collapse of the unconsolidated sediments and possible downward migration of contaminants. 

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