Direct utilization study programs

The phased apprgach developed for environmental assessments has been successfully implemented on a number of programs. The Level 1 results have been useful for defining potential problems for further study and directing additional resources into the areas of greatest need. While not all the elements of the scheme have been found effective on each study, every element has produced needed data in at least one or more of the individual studies. In considering the utility of the approach it is therefore necessary to consider the overall results rather than the value of any single component. 

Radioisotopes that decay by spontaneous fission with the direct accompanying release of neutrons are usually associated with the natural elements of uranium and thorium and the manmade element plutonium. However, the rate of decay of these elements by fission is so slow that it is only by incorporating them into large nuclear piles or chain reactors that they can be utilized as intense neutron sources. In the US Dept of Energy National Transplutonium Program, small quantities of elements heavier than plutonium are produced for basic research studies and to discover new elements with useful properties. One of these new elements, californium-252 (2S2Cf), is unique in that it emits neutrons in copious quantities over a period of years by spontaneous fission... 

A comprehensive program for utilization of APCS by-products is currently underway. This five-phase program covers (1) nationwide environmental survey of present waste products and ecological data relating to the needs of potential APCS customers (2) determination of physical and chemical properties of waste products (3) studies on direct disposal of both solid and liquid wastes (4) beneficiation and use of liquid and solid waste products (5) pilot plant studies of promising utilization procedures. 

Because safety depends on all personnel involved in a particular operation, the individual must not be neglected in planning a safety program. An effective procedure utilizes one or more safety groups or committees to study new problem areas, review existent procedures, and conduct periodic surveys of all laboratories. Such groups should report directly to the head of the safety department or to the research director. The most successful groups have the full cooperation of top management this cooperation emphasizes the importance of safety. 

Nonlinear problems— NLP and MINLP—can be further classified as convex or nonconvex, depending on the convexity of the objective function and feasible region. The understanding of the type of problem in terms of classification and convexity is very important in the utilization of modeling systems, since there are specific solvers and solution techniques for each type of problem, and depending on the problem, there may be local and global solutions. A more comprehensive study on mathanati-cal programming topics and continuous nonlinear optimization is out of the scope of this chapter. The interested reader is directed to references [4,6,7]. 

In principle, any type of magnetic or quadrupole mass spectrometer can be utilized for the analytical pyrolysis of organic materials, if a direct introduction system capable of producing a desired tempera-ture/time profile is available. For example, direct insertion probes (DIPs) and direct exposure probes (DEPs) are Avidely used for sample introduction and such probes are supplied with control units that allow heating and temperature programming of the sample up to 500-800°C. Therefore, such modules should be considered as the most readily available probes for Py-MS studies. 

---