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The principles of cleaning and sterilising of stainless steel plant and equipment are not always understood by those responsible for these operations with the result that corrosion of stainless steel can take place. However, if properly planned routines are followed, stainless steel should be virtually indestructible.

Despite evidence indicating that socioeconomic status is multidimensional, health behavior research frequently “controls for” education or income as monolithic indicators of SES. Education and income (as well as other SES indicators) tap different aspects of SES, are only moderately correlated, and can each independently influence behavior. The specific aims of this study were to: (1) describe and disaggregate the association between different indicators of socioeconomic status—educational attainment, employment status (as a proxy for occupational status), individual income, and household income—and multiple health behaviors; (2) examine the pattern of association between SES and health behaviors by gender; and (3) explore different hypotheses linking SES and health behaviors. In this study, like previous work, educational attainment had the most consistent relationship with different health behaviors, particularly among men. However an interesting pattern of associations between different dimensions of SES and different health behaviors emerged in multivariate analyses, as did several gender differences. Although fewer psychological resources (i.e. higher levels of depression and lower feelings of control) explained the SES disadvantage in terms of sedentary living, little evidence of mediation was found for other SES-health behavior linkages. Results from this study suggest that multiple aspects of socioeconomic disadvantage can undermine various behaviors related to health. Health interventions targeting lower status populations may need to incorporate specific strategies addressing different aspects of social class.

EACH September the eyes of the aeronautical World turn towards the S.B.A.C. Air Display and Exhibition with interest unequalled by any other event. It is fitting that the Display is now held each year at the airfield of the Royal Aircraft Establishment, one of the world's most prominent aeronautical research centres. This interest becomes increasingly keen too, as the preview day comes closer, because new prototypes of unorthodox designs often appear a short time before the Show to illustrate the results of years of careful planning, development and research of the particular company. These designs often mould the path of progress for smaller countries without the economic resources to forge the way ahead alone. Most British citizens are very proud of their country's place in aviation today, both in the military and civil fields. This is understood by most foreigners because it is clear that Britain has won a place in aeronautical development second to none.

THE Rolls‐Royce Conway R.Co.42 by‐pass turbojet engine is scheduled to enter airline service in 1964, with the Vickers VC10 long‐range transport. The engine has a take‐off thrust rating of 20,370 lb. (minimum guaranteed), and a somewhat higher thrust version, the R.Co.43 of 21,825 lb. will power the larger Super VC10. Fifty‐two of these aircraft are on order by British Over‐seas Airways Corporation and other airlines, and Royal Air Force Transport Command. The five VC10's for the R.A.F. will use the R.Co.43.

It has often been said that a great part of the strength of Aslib lies in the fact that it brings together those whose experience has been gained in many widely differing fields but who have a common interest in the means by which information may be collected and disseminated to the greatest advantage. Lists of its members have, therefore, a more than ordinary value since they present, in miniature, a cross‐section of institutions and individuals who share this special interest.

The Ministry of Health have issued a draft Order by which it is proposed to amend the Public Health (Preservatives, etc.) Regulations made on August 5, 1925. The new proposals give statutory effect to concessions which have previously been announced as to the date on which the Regulations become operative; and include glycerine in the list of articles which do not come within the official definition of “preservative.”

ON September 6, Mr. Cyril F. Uwins, in a Vickers Vespa biplane fitted with a Bristol Pegasus engine, starting from Filton Aerodrome, Bristol, reached a height of 13,404 metres (43,976224 ft.), landing at Evesham, some 50 miles away, after a flight of a little over 2 hours. This is being submitted to the Federation Aeronautique Internationale as a new world's altitude record, the old record of 13,157 metres (43,181 ft.) having been set up by Lieut. Apollo Soucek, of the United States Navy, at Washington in a Wright Apache biplane with a 450‐h.p. Pratt and Whitney engine on June 4, 1930.

This study aims to further the understanding of support structures and the likely impacts on maraging steel MS1 parts fabricated by selective laser melting (SLM) at 45°, 60° and 75° building angles.

Two groups of samples, one group with support structures and the other group without support structures, were designed with the same specifications and printed under the same conditions by SLM at 45°, 60° and 75° building angles. Differences in dimensional accuracy, surface roughness, Vickers microhardness, residual stress and microstructure were compared between groups.

The results showed that with support structures, more accurate dimension and slightly higher Vickers microhardness could be obtained. Larger compressive stress dominated and was more uniformly distributed on the supporting surface. Without support structures, the dimension became more precise as the building angle increased and alternating compressive and tensile stress was unevenly distributed on the supporting surface. In addition, the surface roughness of the outer surface decreased with the increase of the built angle, regardless of the support structures. Furthermore, whether the building angle was 45°, 60° or 75°, the observed microstructures revealed that the support structures altered the orientation of the molten pool and the direction of grain growth.

This paper studies the influence of support structures on the workpieces printed at different building angles. Support structures affect the residual stress distribution, heat dissipation rate and microstructure of the parts, and thus affecting the printing quality. Therefore, it is necessary to balance the support strategy and printing quality to better apply or design the support structures in SLM.

In beginning its work at the end of the 1950s, the Aslib Research and Development Department inevitably faced the task of identifying the most significant problems for investigation, at the same time having the need to establish appropriate experimental techniques. Most of the projects undertaken since that time have dealt with current problems, and to an extent the advent of new technologies and techniques to the information world (mechanization in the 'sixties, management studies in the early 'seventies, on‐line working and publication problems in more recent years) is reflected in the work reported below. What follows is a complete bibliography of publications by members of the Department from its formation up to the end of 1977.

This paper aims to systematically investigate the effect of the heat treatment process parameters on the microstructure and mechanical properties of the selective laser melting (SLM) AlSi10Mg alloy.

The samples with very low porosity were fabricated with optimized processing parameters on a self-developed SLM system. The heat treatment of using the temperature of 170°C∼400°C and the holding time of 0.5∼12 h was studied, and the evolution of the microstructure and mechanical properties of AlSi10Mg alloy under direct aging and annealing was investigated and obtained.

After annealing above 300°C for 1 h, the dendrite Si in the sample occurs spheroidization, and the molten pool contour becomes blurred or even disappeared completely, but low-temperature heat treatment does not change the morphology and size of grains significantly. Except for holding at 200°C for 1 h, all other heat treatment processes cause the tensile and yield strengths of SLM AlSi10Mg alloys to decrease and the elongation to increase. When the annealing temperature is higher than 200°C, the higher the temperature and the longer the holding time, the more obvious this effect is.

The correlation between the mechanical properties and microstructure of SLM AlSi10Mg alloy under different conditions was obtained. According to the characteristics of SLM forming, the direct aging and annealing process are mainly studied, which provided new information for the heat treatment of SLM AlSi10Mg alloy and promoted the engineering application of SLM AlSi10Mg alloy.