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As a result of reorganisation within the Company, AVX Limited have appointed Keith France as General Manager, Sales and Marketing. Previously General Manager, Sales, Europe, Mr France now assumes the added responsibility for the marketing of AVX products throughout Europe.

EXPERIMENT SHOWS that plane compressed plates can resist, in certain cases, loads greater in value than the critical load of buckling. Hence the plates can be used after the phenomenon of buckling, a fact which is of considerable importance especially when reduction in weight of the supporting structures is required.

Examines some of the recent technical developments that are leading to a wider use of powerful methods in medical microscopy.

Reviews some of the microscopic techniques relevant to medicine, then looks at hardware developments in microscopes, filters and cameras.

Highly sophisticated techniques such as time‐resolved fluorescence measurements are now incorporated in turnkey instruments, using picosecond diode lasers for accurate measurement of fluorescent lifetimes. Advances in optical fibre coating technology in the telecoms field have led to improved filters for fluorescence microscopy, and imaging allows the detection of non‐visible wavelengths and very low light levels. Many microscopes are modular, so that users can upgrade to further capabilities at will. Automatic medical diagnosis software is coming onto the market.

Highlights the hardware and software developments that are enabling powerful microscopic methodologies to enter into general use.

WITH record attendances during the first days of the Motor Show this year, Exhibitors are asking if it would not be possible to have certain times, or days, reserved for trade buyers. The promoters are obviously concerned with any possible loss of gate money, but it is very true that at times, when stands are crowded with mere sight‐seers it is very difficult for genuine potential buyers and trade personnel to see what they want in the short time that may be at their disposal. These record attendances may not be repeated always; this year is the first time for a long time that anyone can order any car with a reasonable delivery date, and most cars with only a few weeks wait.

ROBERT LOUIS STEVENSON would have delighted in the deep irony of his own idle words, penned in a letter to William Archer in October 1887. His early death in Samoa, itself a symbolic reflection of an incredibly romantic life, short but full of incident and perfectly constructed for journalistic highlighting, inspired a spate of fulsomely admiring biographical studies which at one time threatened to obscure his true talent. Essay upon essay, book after book, some merely appreciative, some approaching adulation, poured from the presses until literary criticism proper was engulfed in a myth of quite extraordinary dimensions.

The purpose of this study is to investigate the mechanisms of degradation of aluminum metallization under conditions of thermal shock caused by rectangular current pulses (amplitude j < 8 × 10¹⁰ A/m², duration t < 800 μs).

The results were obtained using oscillography and optical microscopy and through the construction of an empirical model of the thermal degradation of metallization systems.

Initially, for the authors’ studies, they deduced an equation that associated the depth of melting with the parameters of a current pulse.

The authors were able to observe effects only in systems with appropriate adhesion of the thin metal films. For the systems with bad adhesion, the main mechanisms of degradation were associated with the melting of the metal, the formation of melted drops (up to 20 mcm in size) and the movement of these drops along the electrical field due to the electrocapillary effect.

The mechanisms the authors studied could only occur in high-power semiconductor devices.

The principal mechanism of melting of a metallization track is linked to the heat dissipation at the interface of solid and liquid phases under conditions of thermal shock. The authors estimated the mechanical stresses in subsurface layers of silicon in the proximity of a non-stationary thermal source. The authors’ results show that the mechanical stresses that are strong enough to form dislocations emerge with current flow with power measuring approximately 0.7 Pkr.