Simulations of the effects of tin composition gradients on the superconducting properties of Nb3Sn conductors

In powder-in-tube (PIT) Nb3Sn composites, the A15 phase forms between a central tin-rich core and a coaxial Nb tube, thus causing the tin content and superconducting properties to vary with radius across the A15 layer. Since this geometry is also ideal for magnetic characterization of the superconducting properties with the field parallel to the tube axis, a system of concentric shells with varying tin content was used to simulate the superconducting properties, the overall severity of the Sn composition gradient being defined by an index N. Using well-known scaling relationships and property trends developed in an earlier experimental study, the critical current density for each shell was calculated, and from this the magnetic moment of each shell was found. By summing these moments, experimentally measured properties such as pinning-force curves and Kramer plots could be simulated. We found that different tin profiles have only a minor effect on the shape of Kramer plots, but a pronounced effect on the irreversibility fields defined by the extrapolation of Kramer plots. In fact, these extrapolated values H_K are very close to a weighted average of the superconducting properties across the layer for all N. The difference between H_K and the upper critical field commonly seen in experiments is a direct consequence of the different ways measurements probe the simulated Sn gradients. Sn gradients were found to be significantly deleterious to the critical current density Jc, since reductions to both the elementary pinning force and the flux pinning scaling field H_K compound the reduction in Jc. The simulations show that significant gains in Jc of Nb3Sn strands might be realized by circumventing strong compositional gradients of tin.Comment: 10 pages, 8 figures, 2 tables, submitted to J. Appl. Phy

A follow-up of the PFS-AV, an assessment instrument for hostility

This follow-up study presents psychometric data and norms of the Adapted Version of the Picture-Frustration Study (PFS-AV) from 422 male violent forensic psychiatric in- and outpatients, 101 male violent long-term prisoners, and 319 secondary vocational students (160 males and 159 females). The PFS-AV is a production instrument to measure hostility with 12 items. A diagnostician scored the responses on a seven-point scale, running from not at all hostile (0) to extremely hostile (7). Support was found for the PFS-AV construct, concurrent, and discriminant validity in all three samples. Therefore, the present results underline the generalizability and applicability of the PFS-AV in different populations. Furthermore, for clinical diagnosis, norms are presented for the three samples, just as examples for the scoring on the Likert scale. Also, Dutch, English, and German versions of the PFS-AV with scoring instructions are available. © 2022 The Author(s). Published with license by Taylor & Francis Group, LLC

Forensic psychiatric outpatients with sexual offences: Personality characteristics, aggression and social competence.

Contains fulltext : 47810.pdf (publisher's version ) (Closed access

CERN–ELIN Nb3_{3}Sn Dipole Model

This chapter reports on the European Organization for Nuclear Research (CERN)–ELIN Nb$_{3}$Sn dipole program. In this program a 1 m long model magnet was built, using Nb$_{3}$Sn superconductor. The Nb$_{3}$Sn magnet reached field levels of 9.5 T in the full dipole and 10.2 T in the magnetic mirror configuration in a 50 mm bore

Aggression Replacement Training for Violent Young Men in a Forensic Psychiatric Outpatient Clinic

The effects of Aggression Replacement Training (ART) were explored in a group of Dutch violent young men aged 16 to 21 years, who were obliged by the court to follow a treatment program in a forensic psychiatric outpatient clinic. To evaluate the training, patients completed a set of self-report questionnaires at three moments in time: at intake/before a waiting period, after the waiting period/before the training, and after the training. During the waiting period, the patients did not change on most measures, although they displayed a significant increase in anger. The patients who completed the therapy scored significantly lower on psychopathy than the patients who dropped out. The training produced significant decreases in physical aggression and social anxiety and showed trends toward a decline in self-reported hostility, general aggression, and anger. After the training, the patients scored comparably with a reference group on measures of hostility and aggressive behavior. Altogether, these results provide tentative support for the efficacy of the ART for violent young men referred to forensic psychiatric outpatient settings