Plant water content monitoring

The radionuclide ameridum-241 emits alpha particles, which produce neutrons by an (a,n) nuclear reaction with light elements. A mixture of americium-241 with beryllium produces 1.0 x 10 neutrons per second per gram of Am. A large number of Am-Be sources are in daily use world-wide in oil-well logging operations to measure the amount of oil produced in a given period of time. These sources have also been used to measure the water content of soils, and to monitor process streams in industrial plants. Am itself has extensive uses in dissipating... 

Gas streams for the experimental reactor contained nitrogen, hydrogen, carbon monoxide, sulfur dioxide, and in some cases oxygen, from cylinders, which were blended to synthesize a mixture of reformed natural gas and a sulfur dioxide-bearing gas stream of the desired composition. The composition of this head gas stream was continuously monitored by an on-line process chromatograph. The mixed gas stream was saturated with water vapor at a controlled temperature and pressure to provide a water vapor content consistent with that in actual plant operation. 

Prevention of the escape of radioactive substances and chemicals in aqueous solutions into the environment is accomplished by setting up processing of aqueous process and drain solutions in the plant s process flows. The plant uses monitored discharge of the water used to cool apparatus, by employing automatic interlocks in the event of a hardware leak. The content of radionuclides in harmful chemicals and waste water is determined by collecting and later analyzing samples. 

The principal structural features are as follows ceiling and walls are 1/4" thick methacrylate plastic floor and structural elements were aluminum. Approximate dimensions are 1 x 2 x 3 M. A heat exchanger supplied by external chilled water provided temperature and humidity control. Sensors buried in the vermiciiite or sand support medium allowed monitoring of soil moisture content. Carbon dioxide was provided from external cylinders, and nutrient was supplied to each plant through a sealed bulkhead. Alternatively, solid inorganic nutrient was provided from a pellet buried in the sand/vermiculite soil medium, and the condensed water of transpiration recycled and distributed to each plant by means of an automatic dispenser controlled by a preset timer. This system was probably most satisfactory from the viewpoint of eliminating periodic additions of external liquid nutrient and subsequent withdrawal of the condensed water of transpiration. 

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