Occupational airway diseases in the metalworking industry Part 1: Respiratory infections, pneumonia, chronic bronchitis and emphysema

Occupational airway diseases are now receiving attention in industry, although study is hampered by a lack of readily-available data. The interpretation of the data that is available, and also of the root problems themselves, is itself a difficult problem. This paper has been written as a literature review which it is hoped that other researchers can take either as a starting point or as a refresher.     

“Metallisation” of oxide surfaces observed by in situ high-resolution electron microscopy

Intense irradiation (25–40 A/cm²) at intermediate energy (400 keV) has been found to cause “metallisation” of tungsten oxide and titanium niobate crystal surfaces. The possible mechanisms and the likely consequences for high-resolution imaging of clean oxide surfaces are briefly discussed.     

Analog VLSI model of binaural hearing

The stereausis model of biological auditory processing is proposed as a representation that encodes both binaural and spectral information in a unified framework. A working analog VLSI chip that implements this model of early auditory processing in the brain is described. The chip is a 100000-transistor integrated circuit that computes the stereausis representation in real time, using continuous-time analog processing. The chip receives two audio inputs, representing sound entering the two ears, computes the stereausis representation, and generates output signals that can directly drive a color CRT display. Outputs from the chips for a variety of artificial and speech stimuli are shown.     

ZnGa2O4纳米晶的制备和结构表征

采用喷射共沉淀法制备了ZnGa2O4 纳米晶，XRD、SEM和TEM结构分析结果表明，喷射共沉淀法制备的ZnGa2O4的纳米晶颗粒细小均匀，形状完整，与化学共沉淀法相比，粒子尺寸明显减小，小于10nm，同时ZnO杂相峰消失，分析了喷射共沉淀法的机理，并对实验结果进行了解释。     

On the development of a direct method of determining the microcrack resistance curve

This report deals with direct observations of microcrack linkage at the crack tip prior to macroscopic crack initiation. It is shown that this process is directly linked to the inclusion distribution in the material and can be considered in terms of an R curve to describe microcrack development.     

The contact of elastic regular wavy surfaces

A complete solution in closed form to the elastic contact of a one-dimensional sinusoidal surface with a flat surface was presented by Westergaard in 1939. This paper is concerned with the elastic contact of a two-dimensional sinusoidal surface with a flat. In this case the stress distribution within the elastic solids is three-dimensional. As the load is increased the contact areas change in shape from being circular to square and finally leave a circular region of no contact when the waves are almost squashed flat. The problem is solved in general using a numerical method due to Kalker, but asymptotic solutions in closed form have been found for light loads and also for heavy loads at which contact is almost complete. The variation of the mean separation with load, which determines the volume of the space trapped between the two surfaces, is also found.     

The effect of a solid additive on rolling fatigue life

Behaviour of a series of lubricant oils and the effect of a non stoichiometric inorganic compound, as solid extreme pressure additive, on rolling fatigue life are studied using the rolling four-ball accelerated service simulation test proposed by Barwell and Scott. The results show, in all tested cases, the remarkable efficacy of this type of additive. The Total Acidity Number (tan) was found to increase with performance time for the case of the base lubricant, while for the oils with additives, it remained at its constant low value. This led to a proposal of a possible mechanism of the additive performance in the rolling process.