Zero emissions design problem

The objective of this book is to develop a creative and integrated approach of a process design problem by means of a systemic viewpoint and of systematic techniques. In this context, systems approach means the design of a complex interconnected system of units to satisfy agreed-upon measures of performance, as high economic efficiency of raw materials and energy, down to zero waste and emissions, flexibility and controllability faced with variable production rate, etc. 

In NEA Si cold cathode devices, a planar diode is biased to inject electrons from an n-type substrate to a p-type NEA surface layer, where current is drawn off by an electric field. (Other cold cathodes of different design have been demonstrated in III-V structures [5.130-132].) This efficient emission could be useful in replacing hot (thermionic) cathodes in IR sensitive devices where a low luminence source with small electron energy spread is desirable, but requirements of zero contamination along with electron emission-density restrictions and long-term instability problems have so far prevented practical use. 

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