24 research outputs found
Transport Properties and Exponential n-values of Fe/MgB2 Tapes With Various MgB2 Particle Sizes
Fe/MgB2 tapes have been prepared starting with pre-reacted binary MgB2
powders. As shown by resistive and inductive measurements, the reduction of
particle size to a few microns by ball milling has little influence on Bc2,
while the superconducting properties of the individual MgB2 grains are
essentially unchanged. Reducing the particle size causes an enhancement of Birr
from 14 to 16 T, while Jc has considerably increased at high fields, its slope
Jc(B) being reduced. At 4.2K, values of 5.3*10^4 and 1.2*10^3 A/cm^2 were
measured at 3.5 and 10 T, respectively, suggesting a dominant role of the
conditions at the grain interfaces. A systematic variation of these conditions
at the interfaces is undertaken in order to determine the limit of transport
properties for Fe/MgB2 tapes. The addition of 5% Mg to MgB2 powder was found to
affect neither Jc nor Bc2. For the tapes with the highest Jc values, very high
exponential n factors were measured: n = 148, 89 and 17 at 3.5, 5 and 10T,
respectively and measurements of critical current versus applied strain have
been performed. The mechanism leading to high transport critical current
densities of filamentary Fe/MgB2 tapes based on MgB2 particles is discussed.Comment: Presented at ICMC 2003, 25-28 May 200
Analytical protocols for characterisation of sulphur-free lignin
Interlaboratory tests for chemical characterisation of sulphur-free lignins were performed by five laboratories to develop useful analytical protocols, which are lacking, and identify quality-related properties. Protocols have been established for reproducible determination of the chemical composition and functional groups, such as phenolic hydroxyl and carboxyl groups of alkaline lignins from annual fibre sources. The lignins studied, were precipitated from black liquors of alkaline pulping of annual fibre crops, flax, hemp and straw. The total (Klason and acid soluble) lignin contents of these lignins range between 83 and 97%. Contaminants may be present, such as sugar residues
Wanted!:virtual coach for people with thorny diseases
Abstract
The main objective of this study was to propose a concept for a virtual coach to be used by people who suffer from costly and challenging diseases such as dementia, depression, diabetes and cardiac related issues, and by their caretakers presenting healthcare service providers or family members of the people suffering from the named diseases. Those listed diseases form almost an unbearable burden for individual persons, their next-of-kin, and those providing health services. The construction of the concept was based on earlier knowledge, and guidelines proposed for design science research were applied. The proposed concept is to sketch a virtual coach that utilizes sensor-based data and written diaries, and that helps patients and their caretakers to get accurate and individual information to support everyday life and healthcare