Plastics repair techniques

Laser is a recent innovation in rework and repair. The fundamentals of laser for initial soldering or for repair have already been discussed in Chap. 47. In the commercial incarnation of this technique, a laser beam is quickly scanned around component leads or, package surface, in the case of area-array devices such as EGAs and chip-scale packages (CSPs). It is most effective for plastic packaged components rather than the thermally massive CBGAs, CCGAs, and so on. In this technique, the component body is heated. Otherwise, there is little difference between this and alternative rework or repair techniques. 

Electrical endurance data, including that for plastic insulation, are frequently analysed using a Weibull statistical technique (see Section 8.17). Three ageing models are used in the literature thermodynamic [29], space charge life [30] and electrokinetic endurance [31]. As summarised in [32], they share some similarities in that they assume that there are several stages in the ageing process and that the dominant one involves the rupture and repair of chemical bonds within the plastic. The space charge life and electrokinetic... 

The scheme in Figure 1 has implicit within it a kinetic approach to the study of DNA damage and repair and its relationship to desirable and toxic consequences of antineo-plastic, DNA reactive drugs In this paper the stepwise approach to the study of this scheme for one agent, cis-DDP, is presented. The initial selection of cis-DDP was made because of its clinical efficacy and the availability of an Inactive isomer Q). We had hoped that some critical DNA lesion would be more efficiently produced by the active compound The development of the alkaline elution technique incorporating enzymatic deproteinization to distinguish between interstrand and DNA-protein crosslinking was critical for this analysis ) ... 

Cranial defects can be caused by injury, infection, or tumor invasion. Large defects should be restructured to protect the brain by using cranial implants. The conventional method is to cover the defect with bone cement. Nowadays, custom-made implants designed for the individual patient are available. Rapid prototyping techniques and medical-grade plastics allow surgeons to repair large holes in skulls. 

Bertin G, Averbeck D (2006) Cadmium cellular effects, modifications of biomolecules, modulation of DNA repair and genotoxic consequences (a review). Biochimie 88(11) 1549-1559 Beyersmann D, Hartwig A (2008) Carcinogenic metal compounds recent insight into molecular and cellular mechanisms. Arch Toxicol 82(8) 493-512 Bode P, De Bruin M, Aalbers TG et al (1990) Plastics from household waste as a source of heavy metal pollution. An inventory study using INAA as the analytical technique. Biol Trace Elem Res 26-27 377-383... 

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