Effects-based targeting/operations

The typical parameters for the PLD of epitaxial ZnO-based thin films on sapphire including information about target preparation are listed in Table 7.3. Within the range of these software controlled parameters, the properties of the deposited films differ widely, as will be shown in Sect. 7.4. Beside the parameters listed in Table 7.3, the film properties will be influenced furthermore by a few more internal effects, which will be listed and discussed in the following according to the scheme effect/problem-cause-solution. Only the careful consideration of all these hidden effects by experienced operators can ensure the highest quality and reproducibility of PLD grown films. 

Run away chemical reactions Corrosive acid and base chemicals of tile isotope production process, less tiian 400 ml per target -Operations are in the SCBs and involve only small pre-measured quantities of addic or basic chemicals in syringes or a closed container. Prepared as kits for one target in a separate fecility, the syringes are introduced to the SCBs and used only as needed. -Quality control analysis operations involve only small quantities (less than a liter) of chemicals that are prepared in a separate cility. -Minimal to no secondary effects. 

Because the operative mechanisms in a hgand-based targeting system and a tissue-specific promoter system are distinct, combining these two types of targeting into a single delivery system should lead to a synergistic effect and result in highly tissue- specific expression. 

In the use of temperature measurement for control of the separation in a distillation column, repeatability is crucial but accuracy is not. Composition control for the overhead product would be based on a measurement of the temperature on one of the trays in the rectifying section. A target would be provided for this temperature. However, at periodic intervals, a sample of the overhead product is analyzed in the laboratory and the information provided to the process operator. Should this analysis be outside acceptable limits, the operator would adjust the set point for the temperature. This procedure effectively compensates for an inaccurate temperature measurement however, the success of this approach requires good repeatability from the temperature measurement. 

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