This paper discusses the possibility to represent scientific development by second-order networks in different modalities. In particular, a specific modality structured by subfield-to-subfield relations is presented. By constructing such co-subfield maps for successive periods of time, we were able to describe the changing subfield relations within the field of chemical engineering. In this way, dynamical processes in the development of a field as a whole can be revealed. Advantages and disavantages as compared to co-citation and co-word mapping techniques are discussed and the importance of developing combined techniques is stressed.
We carefully selected a group of chemical engineering scientists internationally recognized as top-scientists in their field. A method has been developed to systematically compare bibliometric characteristics of these top-scientists with an average scientist in chemical engineering. This method also includes citation-analysis of books and proceedings. The results show a very clear bibliometric profile. First, top-scientists references are more numerous and, fourth, they concern more recent literature. Our fifth findings is that the journals used by top-scientists for their publications are representative for the field of chemical engineering as a whole. But they differ in specific aspects significantly from the average journal structure in chemical engineering: the published work of top-scientists is both general as well as more specialistic than the average work in chemical engineering.
In this paper we apply co-author analysis to create from a large set of publications clusters of collaborating researchers within a faculty of chemical engineering. Results have been discussed with an expert. The co-author clusters appeared to be meaningful, with respect to the identification of research groups, the relations within these groups, as well as to relations between these groups and changes in time. Also differences between ISI-based and non-ISI based maps proved to be consistent with the expert's opinion. Many clusters represent collaborating authors grouped around a full professor, mostly the department chairman. Co-author analysis can be used, for example, as an important tool in evaluative bibliometrics in order to make a first identification of research groups in unknown universities or organizations.
The thermal behaviour of C-type PrO1.50, A-type PrO1.50 and PrO1.833 was investigated by thermodilatometric and DTA measurements in the temperature range from 20 to 1200 °C in air and in a hydrogen atmosphere. The phase transition C-type PrO1.50 → A-type PrO1.50 proceeds at 790±10 °C; C-type PrO1.50 is stable only below this temperature, but A-type PrO1.50 in the whole range. Pro1.833 is stable up to 400 °C at atmospheric pressure. When heated further it decomposes stepwise forming several defined intermediate oxide phases.
Authors:R. Forstner, G. Peters, C. Rendina, J. Housmans, and H. Meijer
A novel dilatometer has been used to measure the evolution of specific volume at different cooling rates and at elevated pressures
under quiescent conditions and under shear for a series of commercial iPP homopolymers and polypropylene–ethylene random copolymers.
Significant influences of cooling rates, pressures, and shear flow on the transition temperature Ttr related to molecular weight and polydispersity and of course the temperature at which shearing was applied could be found
for the iPP homopolymers. In the copolymers, the composition defined by the ethylene content determined the position of the
transition temperature Ttr.