‘Examples of posing’

Abstract

EXAMPLE is proverbially better than precept. ‘Things seen are mightier than things heard’. If this be generally true in relation to manners and morals, it is very specially true in matters of art. The sight of one good picture affords more instruction than many chapters on composition and chiaroscuro or the balance of lines and tones. In relation to posing the human figure, example is an imperative element of all instruction; and variety of example is necessary to suggest varied possibilities of effect, even to fertile minds. There is no piece of advice we have more frequently urged upon the photographic student than this: lose no opportunity of studying the works of great artists and note how their effects of grace, ease, beauty and dignity are secured. Sir Joshua Reynolds has pointed out the great value of this study, and told of his own mode of pursuing it, making an accurate analysis of the proportions of light and shade present, and of their mode of distribution. The aim of this mode of study is to fill the mind with a knowledge of effects, so as to afford material for suggestion in producing original work, not with a series of memoranda to guide the memory in producing imitations. In photography, fortunately, slavish imitation of paintings is scarcely possible, for few artists have painted their pictures so that the effects all come within the range of photographic possibility.     

Investigation of micro-scale abrasion–corrosion of WC-based sintered hardmetal and sprayed coating using in situ electrochemical current-noise measurements

The micro-scale wear–corrosion interactions of WC-based sintered hardmetals and sprayed coatings are typically investigated by comparing the wear-rates in corrosive environments with neutral (pH 7) conditions and inferring electrochemical activity. However, for a greater understanding of the wear–corrosion interactions, there is a need to examine the repassivation kinetics during micro-abrasion tests under different pH conditions. This paper details in situ electrochemical current-noise measurements performed using a modified micro-abrasion tester to elucidate these wear–corrosion interactions for pH 7–13 conditions for sintered WC–5.7Co–0.3Cr and sprayed WC–10Co–4Cr specimens. Electrochemical measurements and SEM micrographs of worn surfaces are used to detail the degradation process. Discussion will focus on the wear–corrosion interactions present under neutral and alkaline conditions for sintered and sprayed specimens and the influence of microstructure on the electrochemical activity will be detailed.     

A ‘3-body’ abrasion wear study of bioceramics for total hip joint replacements

The current study focuses on the effect of the material type and the lubricant on the abrasive wear behaviour of two important commercially available ceramic on ceramic prosthetic systems, namely, Biolox^® forte and Biolox^® delta (CeramTec AG, Germany). A standard microabrasion wear apparatus was used to produce ‘3-body’ abrasive wear scars with three different lubricants: ultrapure water, 25 vol% new-born calf serum solution and 1 wt% carboxymethyl cellulose sodium salt (CMC-Na) solution. 1 μm alumina particles were used as the abrasive. The morphology of the wear scar was examined in detail using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Subsurface damage accumulation was investigated by Focused Ion Beam (FIB) cross-sectional milling and Transmission Electron Microscopy (TEM). The effect of the lubricant on the ‘3-body’ abrasive wear mechanisms is discussed and the effect of material properties compared.     

Application of a 2-beam model for improving the structure factors from precession electron diffraction intensities

A 2-beam model is used to simulate precession electron diffraction (PED) intensities. It is shown that this model can be inverted with minimal knowledge of the underlying crystal structure, permitting structure factor amplitudes to be deduced directly from measured intensities within the 2-beam approximation. This approach may be used in conjunction with direct methods to obtain correct, kinematically interpretable structure indications for data sets from relatively thin crystals (less than approximately 400A), and an experimental example based on (Ga,In)(2)SnO(5) is presented. The failure of this approach at large thickness is illustrated by an additional data set for MFI zeolite. The 2-beam approximation provides a simple model for PED intensities, and inversion using this model shows advantages over a kinematical approximation. It is however too rough approximation to be of general use and ultimately it is to be hoped that more accurate models with similar ease of use can be derived to treat PED data.     

Template synthesis of gold nanotubes in an anodic alumina membrane

Nanotube-containing membranes prepared by the template method show promise for use as highly selective filters for membrane-based chemical and biological separations. Most of the work to date has been done on gold nanotubes prepared by electroless deposition of Au within the pores of polymeric filtration membranes. These polymeric filters have very low porosities (< 1%), and, as a result, the flux through Au nanotube membranes based on these templates is very low. In contrast, the other popular template membranes-anodic aluminas-have high porosities-30% to 50%. In spite of this potential advantage of anodic alumina templates, there have been no reports of electrolessly plated Au nanotubes within the pores of these templates. This is because the electroless plating method used to deposit Au nanotubes in polymeric templates does not work in aluminas. We have developed a modified electroless plating strategy that can be used to deposit high-quality Au nanotubes within the pores of the alumina templates. We describe this new plating method here.     

Airblast TNT equivalence for a range of commercial blasting explosives

Results are reported from a programme of work undertaken by the UK Health and Safety Executive to investigate the airblast produced by commercial sector explosives having velocities of detonation (VoD) in the range 2000-8200 m s(-1). The data produced will be useful in evaluating the blast hazards of such explosives in industrial circumstances and also as a means of assessing post-accident damage. All of the solid explosive materials studied produced blast waves which ramped up into shock-wave form close to the point of initiation. The dependence of peak overpressure and positive phase impulse on scaled distance is presented and compared to that of TNT. The TNT equivalence (TNT(e)) technique is shown to be applicable to solid phase explosives with a wide range of VoD, although the precise values of TNT(e) vary with distance.