Showing papers by "Brunel University London published in 1985"
TL;DR: In this paper, the fraction of atoms at the surface of small metal particles increases as their size diminishes in the range 10 to 2 nm, and it is shown that certain classes of reaction may be designated as "structure-insensitive" in that their rates depend only minimally on particle size.
226 citations
TL;DR: It is shown that the peak velocity is achieved in the middle stages of the race, a result which is consistent with practice, but which previous calculations based on Newton's laws have failed to predict.
119 citations
TL;DR: In this paper, the elastic moduli of the entire vitreous range of the system CoPO that can be prepared by melting together Co3O4 and P2O5 oxides in open crucibles, have been measured by ultrasonic techniques at 15 MHz.
Abstract: The elastic moduli of the entire vitreous range of the system CoPO that can be prepared by melting together Co3O4 and P2O5 oxides in open crucibles, have been measured by ultrasonic techniques at 15 MHz. The bulk, shear, longitudinal and Young's moduli and the Poisson ratio are found to be rather sensitive to the glass composition. It is found from this ultrasonic data, that the glass system can be divided into “three compositional regions”. This behaviour is qualitatively interpreted in terms of the cobalt co-ordination, crosslink densities, interatomic force constants and atomic ring sizes. Also presented is a full discussion of effects of annealing on elastic properties.
112 citations
TL;DR: The results indicate that handling and confinement only activated the corticotrophs of the pars distalis, not the melanotrophS of the neurointermediate lobe, whereas when combined with a thermal shock, both cell types were activated.
105 citations
TL;DR: Major early perturbations produced to liver endoplasmic reticulum by exposure in vivo or in vitro to CCl4 include covalent binding and lipid peroxidation; studies of these processes occurring during CCl3O2 intoxication have uncovered a number of concepts of general relevance to free-radical mediated tissue injury.
Abstract: A single dose of CCl4 when administered to a rat produces centrilobular necrosis and fatty degeneration of the liver. These hepatotoxic effects of CCl4 are dependent upon its metabolic activation in the liver endoplasmic reticulum to reactive intermediates, including the trichloromethyl free radical. Positive identification of the formation of this free radical in vivo, in isolated liver cells and in microsomal suspensions in vitro has been achieved by e.s.r. spin-trapping techniques. The trichloromethyl radical has been found to be relatively unreactive in comparison with the secondarily derived peroxy radical CCl3O2., although each free radical species contributes significantly to the biological disturbances that occur. Major early perturbations produced to liver endoplasmic reticulum by exposure in vivo or in vitro to CCl4 include covalent binding and lipid peroxidation; studies of these processes occurring during CCl4 intoxication have uncovered a number of concepts of general relevance to free-radical mediated tissue injury. Lipid peroxidation produces a variety of substances that have high biological activities, including effects on cell division; many liver tumours have a much reduced rate of lipid peroxidation compared with normal liver. A discussion of this rather general feature of liver tumours is given in relation to the liver cell division that follows partial hepatectomy.
102 citations
TL;DR: The formation of PBN-free radical adducts has also been observed in phenobarbital-induced rats in vivo when intoxicated with chloroform, bromoform or iodoform, suggesting that the reductive metabolism of trihalomethanes might be of relevance to their established toxicity in the whole animal.
98 citations
TL;DR: A series of glass specimens was prepared from TeO2 glass and from the binary tungsten tellurite glasses (TeO2-WO3) and their densities, optical absorption edges and infrared absorption spectra were measured.
Abstract: A series of glass specimens was prepared from TeO2 glass and from the binary tungsten tellurite glasses (TeO2-WO3) and their densities, optical absorption edges and infrared absorption spectra were measured. It was found that the fundamental absorption edge is a function of glass composition, and absorption in this region is due to indirect electronic transitions in k-space. The main infrared absorption bands in the TeO2-WO3 glasses are related to those characteristics of the TeO2 component.
94 citations
90 citations
TL;DR: In this article, an ion exchange met was used to impregnate a Pt(NH 3 ) 4 2+ onto silica by use of an ion-exchange met, which was prepared specially for this project by Johnson Matthey.
85 citations
TL;DR: In this article, the results of a deep drilling investigation were described, showing that white layers are formed at a hole surface by a combination of high temperatures, pressures, strain rates, cooling rates, and cyclic deformation.
Abstract: This paper describes the results of a deep drilling investigation in which white layers are formed at a hole surface by a combination of high temperatures, pressures, strain rates, cooling rates, and cyclic deformation. A comparison is drawn between the mechanisms involved in deep drilling and thermo-mechanical mechanisms present during rubbing. This comparison provides a clue as to how white layers are created during other machining processes, examples being given for drilling, milling, and grinding.
83 citations
TL;DR: The lower threshold for motion (LTM) of gratings as a function of position in the visual field, spatial frequency and contrast and motion thresholds for sine wave and square wave luminance profiles are investigated to provide support for a ratio model of velocity coding.
TL;DR: In this article, the infrared absorption spectra of the vitreous Co3O4-P2O5 system have been measured in the frequency region 4000 to 200 cm−1.
Abstract: The infrared absorption spectra of the vitreous Co3O4-P2O5 system have been measured in the frequency region 4000 to 200 cm−1. Absorption bands and mode attributions have been fully discussed. Absorption frequencies and intensities are found to be strongly and systematically dependent on glass composition. On this basis it is found that this glass system can be divided into three distinct “compositional regions”. Similar “three region” behaviour is reported for the compositional dependence of density and molar volume of mixing of Co3O4-P2O5 glass. Quantitative justification for the band attributions has been attempted.
TL;DR: The results support a ratio model of velocity coding whose spatial reference varies with eccentricity in approximate accordance with the human cortical magnification factor.
01 Jan 1985
TL;DR: In this paper, a general three dimensional hydroelastic theory applicable to marine structures which may be moving or fixed in regular sinusoidal waves is discussed, with reference to ships, multi-hulls (SWATHS, catamaran, semisubmersible), jack-up rig, fixed plate, etc.
Abstract: Hydroelasticity is that branch of science which is concerned with the motion of deformable bodies through liquids. A floating or fixed marine structure is a flexible body which deforms due to the actions of fluid loadings or other externally applied forces. This paper discusses a general three dimensional hydroelastic theory applicable to marine structures which may be moving or fixed in regular sinusoidal waves. Applications of the theory are illustrated with reference to ships, multi-hulls (SWATHS, catamaran, semisubmersible), jack-up rig, fixed plate, etc.
TL;DR: This paper reviewed the uses and abuses of seriousness surveys and then examined the crime seriousness ratings and rankings of representative samples of the police and public from one Northern and one Southern police force area in England and Wales.
Abstract: This article reviews briefly the uses and abuses of seriousness surveys and then examines the crime seriousness ratings and rankings of representative samples of the police and public from one Northern and one Southern police force area in England and Wales. It concludes that there is high concordance (both among the public and between police and public) on offences such as violence and theft by a police officer, but more disagreement on the rating of frauds, burglary, and "victimless crimes". The police understate the absolute and relative seriousness of business fraud offences, probably because of their occupational culture. Few significant differences appear between offenders and non-offenders or between victims and non-victims. Finally, the policy implications are discussed. In Britain, as in other Parliamentary democracies, "public opinion"— hypothetical or as measured by surveys—is frequently cited as a justification for criminal justice policies: by Sir Kenneth Newman as a rationale for devoting more police resources to street crime in London (Home Office, 1983); by the Director of Public Prosecutions when blaming juror attitudes for the low prosecution rate of offences by the police (though see Williams, 1985, for a critique); by Freedom of Information advocates as a reason for not prosecuting those who leak Official Secrets "in the public interest" (though a jury convicted Ms. Sarah Tisdall for leaking secrets to The Guardian)-, and by sentencers. Attempts to lead public opinion via denunciatory sentences may be ineffectual (Walker and Marsh, 1984), but public sentiments are given pride of place in justifying longer sentences for violent offenders and vendors of illegal narcotics.1 Indeed, the Home Office Working Paper Criminal Justice (1984, p. 7) makes the retributive role of the public quite explicit when it states: "[Sjentences . . . must also reflect the public's view that crimes of violence are evil and deserve punishment . . . [T]he most serious offenders must expect to pay dearly for their crimes." When officials or interest groups wish to disobey vox populi, they make claims to special expertise or to the need to preserve The Law from political interference. There is seldom any attempt to make explicit the moral and/or intellectual basis for such professional autonomy. Rather, even
TL;DR: The motivation for and the basic concepts on which relational-product architectures are built are outlined, and the approach presents a much wider repertory of structures and algorithms for their manipulation.
01 Apr 1985
TL;DR: In this paper, a contrast variation method derived from Rayleigh-Gans-Debye theory for determining the refractive index of colloidal particles by turbidimetry is examined.
Abstract: A contrast variation method which is derived from Rayleigh-Gans-Debye theory for determining the refractive index of colloidal particles by turbidimetry is examined. It is found numerically to apply to Mie particles in the range α|m − 1| < 0.40. Experiments using polystyrene latices of various sizes and colloidal silica show that approximate turbidities measured in a conventional spectrophotometer suffice to give a true estimate of the particle refractive index. Measurement of the refractive index of casein micelles of bovine milk by this method gives a value of 1.570 ± 0.005.
TL;DR: In rats NaCl and NH4Cl (25 mmoles/kg, p.o.) were found to be equally effective at preventing nephrotoxicity when administered to rats 90 min before cisplatin but (NH4)2SO4 did not protect, which suggests that chloride ions may protect against the neph rotoxicity of cisPlatin by inhibiting its rate of metabolism.
TL;DR: It is concluded that the renal tubular transport of platinum is not per se responsible for the nephrotoxicity of platinum compounds, however, in the case of cisplatin, or one of its metabolites, renal Tubular transport may be a prerequisite for neph rotoxicity.
TL;DR: In this article, a number of nitro- and dinitro-1,8-naphthalimides have been prepared as potential fluorescent probes of hypoxic cells, and their susceptibility to nucleophilic displacement of the nitro group has been demonstrated by reaction with 1-butanethiol to yield 4-butylthio derivatives.
TL;DR: In this paper, a series of binary MoO3-P2O5 and also ternary MoO 3-P 2O5-In2O3 glasses were prepared and their electrical properties were investigated.
Abstract: A series of binary MoO3-P2O5 and also ternary MoO3-P2O5-In2O3 glasses were prepared and their electrical properties were investigated. The d.c. conductivity measurements show that the conduction in molybdenum phosphate glasses is by a hopping process in which the electrical charge transfers from Mo5+ to Mo6+ ion sites. The conductivity can be discussed in terms of the small polaron conduction mechanism. In contrast to vanadium phosphate glasses, the tunnelling term in the conductivity formula seems to make a significant contribution in molybdenum phosphate glasses and is associated with a hopping process in the non-adiabatic regime.
TL;DR: The results provide evidence that oscillatory displacement thresholds in the hyperacuity range depend on motion-detecting mechanisms whose spatial dimensions are correlated with M-1.
TL;DR: In this paper, a two-body pin-on-disc testing has been used to investigate the wear of a wide range of experimental steels, a manganese steel and a commercial digger tooth steel for comparison.
TL;DR: Calculations show that the advantage to an athlete of a following wind increases progressively with increasing wind speed, and that a favourable wind of 2 ms-1 provides a benefit of about 0.18 s on running time.
TL;DR: In this paper, the physical parameters such as density, X-ray diffraction, infra-red absorption spectra and optical absorption measurements are discussed with respect to all compositions.
Abstract: The physical parameters such as density, X-ray diffraction, infra-red absorption spectra and optical absorption measurements are discussed with respect to all compositions. The d.c. conductivity was measured for semi-conducting vanadium phosphate glasses containing 5 mol% rare-earth oxides. The conductivity of vanadium phosphate glasses is slightly higher than the corresponding compositions with rare-earth oxides. The heat treatment in the range 300 to 500° C caused progressive microstructural changes which dramatically affected the electronic conductivity (σ) and the activation energy for conduction (W). It was also found that the incorporation of rare-earth oxides did not affect the limits of the ultra-violet absorption edge of the base glass.
TL;DR: In this paper, the stability of solutions to the plane-strain problem of an incompressible isotropic elastic material subject to in-plane dead-load tractions are considered.
TL;DR: The surgical removal of the primary tumour has apparently no effect on the plasma concentrations of 6-keto-PGF1 alpha and TXB2 over a follow-up period of 9 days after operation, indicative of the regulatory power of metabolic systems to preserve the homeostatic balance.
TL;DR: The extended set partitioning model forms the basis of a computer assisted bus crew scheduling system developed by the authors and is in regular use by Dublin City Services in the Republic of Ireland.
TL;DR: In this paper, wear properties of polytetrafluoroethylene (PTFE) and high density polyethylene are tested under combined apparent and imposed rotations of a specimen using a pin-on-disc configuration.