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Abstract  

Pichappan's formulation of the Discipline-Contribution Score (DCS) in the identification of core disciplinary journals is applied to social science literature. Modifications are made to Pichappan's method to cater for problems associated with low citation counts. Further analysis is undertaken to verify Pichappan's claims concerning the size-independent nature of the DCS score. The proposed modified formulation of the DCS calculation facilitates research into small research fields, and those characterised by low citation rates. The modified equation is tested on business and management literature.

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Summary A pseudo-isothermal method for the kinetic analysis was applied to the recrystallisation of a to ß nickel sulphide based on the Ozawa model for non-isothermal crystallisation in the presence of pre-existing nuclei. The aim of the analysis was to determine the number of steps involved in the recrystallisation and, hence, determine the applicability of the kinetic equation based on a single step mechanism, as is commonly applied in the kinetic analysis of solid-state processes using thermal methods. The kinetic analysis yielded evidence of at least two processes indicating that physical and mechanistic significance should not be drawn from the use of a single step approximation of the rate equation.

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Abstract  

Recent years have seen enormously increased interest in the comparative evaluation of research quality in the UK, with considerable resources devoted to ranking the output of academic institutions relative to one another at the sub-discipline level, and the disposition of even greater resources dependent on the outcome of this process. The preferred methodology has been that of traditional peer review, with expert groups of academics tasked to assess the relative worth of all research activity in ‘their’ field. Extension toinstitutional evaluation of a recently refined technique ofjournal ranking (Discipline Contribution Scoring) holds out the possibility of ‘automatic’ evaluation within a time-frame considerably less than would be required using methods based directly on citation counts within the corpus of academic work under review. This paper tests the feasibility of the technique in the sub-field of Business and Management Studies Research, producing rankings which are highly correlated with those generated by the much more complex and expensive direct peer review approach. More generally, the analysis also gives a rare opportunity directly to compare the equivalence of peer review bibliometric analysis over a whole sub-field of academic activity in a non-experimental setting.

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Résumé  

Le dosage de l'oxygène par radioactivation avec les particules chargées alphas et hélions-3 a été appliqué au silicium et au germanium. Des précisions ont été apportées aux conditions opératoires en analyse non destructive qui est utilisable à l'heure actuelle en toute sécurité pour le silicium. Une méthode nouvelle d'isolement du fluor-18 est proposée en présence des activités étrangères créées à partir de la matrice dans l'irradiation du germanium.

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Summary A procedure for the extrapolation of accelerated thermo-oxidative ageing tests to lower temperatures is proposed. The procedure involves a deconvolution of the global process into high- and low-temperature components where the extrapolation to low temperatures is carried out using the low-temperature component. The method was tested on stabilized and unstabilized polyisoprene rubber and was found to produce realistic estimations of the length of the induction period of oxidation so giving a more accurate estimation of the service life. However, to obtain the low-temperature values of the adjustable kinetic parameters, very low heating rates are required (0.04 K min-1, 0.1 K min-1) making the measurement process time consuming. Using this method, more realistic estimates of the durability of a material are obtained.

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Abstract  

The DSC characterisation of the morphology of the metastable a phase of stoichiometric nickel sulphide was carried out using two calorimeters; a TA Instruments 2920 MDSC and a Perkin Elmer DSC-7, and two quenching histories. Based on these quenching histories, significant differences were observed in the heat flow curves, including the observation of a second exothermic peak which is tentatively assigned to be a metastable phase to metastable phase transformation. The kinetic constants for the a to b recrystallisation were determined as a function of degree of conversion using a mechanism free isoconversional model. Variations in the values of the kinetic constants were also ascribed to the quenching histories. Although the differences in morphology observed were ascribed to the processing history, the shift in the position of the a to b recrystallisation peak was partially attributed to the thermal resistances of the instruments used.

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Abstract  

Bone provides an important source of forensic evidence. The storage conditions of bone have been recognised as a factor in maintaining the integrity of such evidence. Thermogravimetric analysis (TG) has been employed to examine the effects of storage environments and preparation methods on the structural properties of pig bones. A comparison of oven and freeze drying has been made to study the effect of storage conditions. A comparison has also been made of ground bone specimens with cut specimens. Freeze-dried hand ground specimens provided the most consistent results and, thus, this is the recommended method of preparation of bone specimens for TG analysis.

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Abstract  

Using the pulse radiolysis competition kinetic technique, OH radical rate constants with 12 metal DTPA complexes were determined in neutral aerated aqueous solutions. They are in the range of /1.3–5.9/×109 dm3 mol–1s–1. To a first approximation, the rate constant was found to decrease linearly with an increase in the field strength of the metal ion (q/r2).

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Abstract  

Nickel sulphide (NiS) was characterised using X-ray diffraction, thermal gravimetric analysis (TG) and differential scanning calorimetry (DSC). The 'as received' Millerite, stoichiometric NiS, observed to be slightly nickel deficient, was found to readily decompose in a nitrogen atmosphere at elevated temperatures (450C max.) to the sulphur deficient Godlevskite, Ni7S6. DSC and X-ray measurements demonstrated that the high temperature form of the Godlevskite was readily stabilised at room temperature. The kinetics of the α-β re-transformation in Godlevskite were then investigated using DSC and were observed to be first order.

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