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The very contextual nature of most mitigating evidence runs counter to America’s individualistic culture. Prior research has found that capital jurors are unreceptive to most mitigating circumstances, but no research has examined the capital sentencing decisions of trial judges. This study fills that gap through a content analysis of eight judicial sentencing opinions from Delaware. The findings indicate that judges typically dismiss contextualizing evidence in their sentencing opinions and instead focus predominately on the defendant’s culpability. This finding calls into question the ability of guided discretion statutes to ensure the consideration of mitigation and limit arbitrariness in the death penalty.

This paper aims to describe some of the European Space Agency (ESA) workmanship standards which are based on industrial practices. Coordination with National Aeronautics and Space Administration (NASA) Centres on workmanship issues is also to be described.

The first ESA (then ESRO) workmanship standard was published in 1972. It applied to the hand soldering of electronic assemblies and became a contractual document, either replacing, or supplementing a vast number of company standards that had existed in European manufacturing companies. Since then some 40 standards related to Materials and Processes have been developed by ESA, the majority of which are to be found in the European Cooperation for Space Standardization (ECSS) series of European standards.

It is shown that, where appropriate, the standards are backed by a number of ESA‐approved skills training schools which provide training courses that result in the certification of operators, inspectors and instructors.

The workmanship standards are periodically revised in order to take into account newly developed technologies, the results of failure analyses (lessons learnt), laboratory and field test results, as well as some particular requests from industry.

The filamentary growths of single crystals on material surfaces are termed whiskers. They are seen to nucleate and grow on certain electronic materials either from vapour and liquid phases or by a process induced by residual stresses in electroplated surfaces. Whisker growth does not depend on the existence of an electric field and surfaces prone to their growth may nucleate and form whiskers as a result of exposure to a space environment. This paper includes a detailed examination of tin whiskers which were found to have 1 to 4 micron diameters and lengths exceeding 2 mm. Some were found to carry currents between 22 and 32 mA before burning out. Conductive whiskers can cause extensive short circuit damage to spacecraft electronics particularly as miniature devices progressively employ closer spacings between conductors. Several modes of whisker growth on spacecraft electronic materials (molybdenum, tungsten, Kovar, tin) have been observed and are described. Tin, cadmium and zinc surfaces can support stress‐induced whisker growth and it is recommended that these metal finishes are excluded from spacecraft design and possibly replaced by a tin‐lead alloy.

This paper aims to present the results of a 32-year-old laboratory study of whisker growth from tin electrodeposits that was originally undertaken to gain an increased understanding of the phenomenon of tin whisker growth.

Whisker growth was evaluated using electroplated C-rings (both stressed and un-stressed) that were stored throughout in a desiccator at room temperature. Analysis has recently been undertaken to evaluate whisker growth and intermetallic growth after 32 years of storage. Scanning electron microscopy analysis has been performed to investigate whisker length and, using polished cross-sections, the morphology, thickness and type of intermetallic formation.

Normal tin-plated deposits on brass and steel with a copper barrier layer nucleated whiskers within five months, and in each case, these grew to lengths between 1 and 4.5 mm. For normal tin electroplated onto brass, a one- or two-month nucleation period was needed before whiskers developed. They reached a maximum length of about 1.5 mm after six months, and little or no further growth occurred during the subsequent 32 years. Very few whiskers grew on the tin-plated steel samples and no intermetallic formation was observed. None of the fused tin plating samples nucleated whiskers during the 32-year period.

Knowledge about vintage whiskers is important to take steps to increase the resiliency of space missions. Similarly, such knowledge is important to engineers engaged in products reaching their nominal end-of-life, but where, for reasons of economy, these products cannot be replaced.

This study represents a unique insight into whisker growth and intermetallic formation over an extremely long time period.

Electronic materials, particularly tin‐lead coated component leads, may degrade and acquire a poor solderability as a result of long‐term storage or prolonged periods at elevated temperatures (during burn‐in). This paper presents the results of studies on the surface chemistry and microstructure of such coatings together with a technique for stripping degraded coatings and replacing them with pristine finishes having excellent solderability.

The transition to surface mounted device (SMD) technology in electronics manufacturing has placed new demands on the post‐solder cleaning process. For spacecraft electronic systems it is of the utmost importance that all flux residues be removed. This paper reports the results of an investigation of the impact of component stand‐off heights and the distance between solder joints on the cleaning process efficiency. The capability to clean beneath large chip carriers was evaluated for four different cleaning methods using isopropanol or CFC‐113 (Freon TMS) as cleaning liquid. The results show that the cleaning efficiency decreases considerably if the stand‐off height is less than 240 µm for 100 mil pitch chip carriers. For 50 mil pitch chip carriers the stand‐off height needs to be greater than 240 µm to achieve high cleaning efficiency. The cleaning efficiency beneath chip carriers with small stand‐off heights can be increased by using ultrasonic cleaning. However, a very thin layer of white residues is left where the flux has been removed if isopropanol is used as the cleaning liquid.

An evaluation programme involving the extensive thermal cycling of component‐assembled printed circuit boards has been undertaken to assess the suitability of ESA‐approved hand‐soldering techniques for use on long‐life satellites. The modes of joint degradation are discussed and the metallurgical changes that result from material thermal expansion mismatch and repeated strain within the solder alloy (63% tin, 37% lead) are highlighted by photomicroscopy.

Solderability testing, according to Military Standard 883, has evolved through four sets of different test conditions during the past ten years. These relate to the duration of artificial steam ageing and the utilisation of either mildly activated or pure rosin flux. The European Space Agency (ESA) has experienced few solderability problems with leadless ceramic chip carriers (LCCCs) supporting tin‐lead finished castellations. However, similar packages having gold on nickel plated finishes will only produce satisfactory solderability results when activated flux is applied to samples exposed to steam ageing for eight hours. A reason for poor solderability is given, based on an evaluation of test samples and metallography. It is concluded that tin‐lead finished devices should be subjected to eight hours of steam ageing followed by solderability testing with pure rosin flux. An ESA prerequisite for soldering is that all gold finishes must be removed, possibly with the aid of RA type fluxes. For this reason it is recommended that RA flux is permitted (when necessary) during the standard solderability test.

Work design has largely overlooked cognitive–emotional interactions in understanding employee motivation and satisfaction. My aim in this chapter is to develop a conceptual model that integrates what we know about these interactions from research on emotions and neuroscience with traditional and emergent work design perspectives. I propose that striving for universal goals influences how a person responds to the work characteristics, such that an event that is personally relevant or “self-referential” will elicit an emotional reaction that must be regulated for optimal performance, job satisfaction, and well-being. A Self-Referential Emotion Regulatory Model (SERM) of work design is presented.