Study of a BGO calorimeter using electron and hadron beams from 1 to 50 GeV

A calorimeter of 25 bismuth germanate (BGO) crystals equipped with silicon photodiode readout has been tested at the CERN SPS in the energy range 1–50 GeV. The response for electrons has been shown to be linear in this energy range and the rms resolution obtained ( ) is approximately 1%, for E > 4 GeV. The electron/pion separation was found to be better than 1:500 in the energy range 1–20 GeV. Data on lateral and longitudinal shower development were compared with the results of a Monte Carlo simulation using the SLAC-EGS program and found to be in good agreement.     

Summary of discussion on ‘Sciences related to pitch and coke usage in carbon manufacture’

This article is a brief summary of the Discussion session held after the presentation of the preceding papers at the conference organized by the Industrial Carbon and Graphite Group of the Society of Chemical Industry, London, March 1984.     

Formation and Properties of Calcium Aluminosilicate Glasses

The glass-forming region for calcium aluminosilicate glasses has been determined. A number of properties of these glasses (thermal expansion coefficient, glass transformation and dilatometric softening temperature, and refractive index) have been studied. The results of these measurements suggeq that the structures of these glasses may not as closely resemble those of alkali aluminosilicate glasses as is commonly assumed. Evidence is presented which suggests that the binary calcium aluminate glasses may be phase separated.     

Phase Studies Concerning Sintering in Aluminas Doped with Ti4+

Previous solid state analyses of sintering in Ti⁴⁺-doped-commercial alumina are shown to be in error because a liquid phase exists in the appropriate region of the Al₂O₃−TiO₃−Na₂Ophase diagram at least by 1350^°C, a temperature lower than that at which "solid state" studies were conducted. It is suggested that liquid-phase sintering is a much more common occurrence than was realized formerly.     

Effects of alloy additions on the microstructures and tensile properties of cast Co-Cr-Mo alloy used for surgical implants

The composition of the Co-Cr-Mo alloy has been modified by additions of nickel and some trace elements aluminium, titanium and boron. In this paper, the first part of the present study, the effects of alloy additions on the microstructures and tensile properties of the as-cast Co-Cr-Mo alloy are discussed. The effects of alloy additions on the fatigue behaviour of the alloy will be discussed in the second part of the present study. It is found that alloy additions do not seem to result in changes in the nature of the casting structure. A directional, coarse dendritic cast structure is produced in the modified alloys as in the base alloY. However, the alloy additions affect the carbide precipitations and the formation of some fine details of the microstructure such as dislocations, stacking faults and twins produced during the solidification. A considerable improvement in the transient mechanical properties, especially in the tensile ductility, is achieved by modifying the base alloy with alloy additions.     

Plastic flow and fracture of Pd40Ni40P20 metallic glass under an indentor

The geometry of plastic flow under spherical and Vickers indentors in Pd₄₀Ni₄₀P₂₀ metallic glass has been investigated by sectioning and etching. The surface pile-ups and slip lines around the indentations are found to be only a small part of the total deformation. Beneath the surface extensive plastic zones are formed in which material is moved radially away from the indentor, but this movement is produced by slip on surfaces of high shear stress rather than by direct radial flow or compaction. Networks of cracks or incipient cracks also form around an indentation but are not normally visible until the material is etched.