ABSTRACT
We performed a feasibility study on a high-strength Bi2-x Pb x Sr2Ca2Cu3O10-x (Bi-2223) tape conductor for high-field solenoid applications. The investigated conductor, DI-BSCCO Type HT-XX, is a pre-production version of Type HT-NX, which has recently become available from Sumitomo Electric Industries (SEI). It is based on their DI-BSCCO Type H tape, but laminated with a high-strength Ni-alloy. We used stress-strain characterizations, single- and double-bend tests, easy- and hard-way bent coil-turns at various radii, straight and helical samples in up to 31.2 T background field, and small 20-turn coils in up to 17 T background field to systematically determine the electro-mechanical limits in magnet-relevant conditions. In longitudinal tensile tests at 77 K, we found critical stress- and strain-levels of 516 MPa and 0.57%, respectively. In three decidedly different experiments we detected an amplification of the allowable strain with a combination of pure bending and Lorentz loading to ≥ 0.92% (calculated elastically at the outer tape edge). This significant strain level, and the fact that it is multi-filamentary conductor and available in the reacted and insulated state, makes DI-BSCCO HT-NX highly suitable for very high-field solenoids, for which high current densities and therefore high loads are required to retain manageable magnet dimensions.
ABSTRACT
Rio Grande do Sul is a state of 10 million inhabitants, with 800 patients on the transplantation waiting list (80 per million population [pmp]/y) with a mean waiting time of 2 years. Up to 2000, there were 11 to 15 cornea donors and 70 to 80 transplantations yearly. Seeking to increase the number of corneas available for transplantation and reduce the time on the waiting list, we initiated a project wherein the hospital transplantation coordinator trained the morgue staff to evaluate all deceased persons. If the person had no contraindication, the morgue staff called the coordinator to interview the family. Whenever donation was authorized, the coordinator communicated with the Cornea Bank to perform a removal. There was a major increase in the number of donations (220/y) with this project responsible for more than 70% of the cornea donors on cardiac arrest in the Rio Grande do Sul State. The mean time on the waiting list decreased to 14 months. This model was efficient, and must be implemented in other hospitals in the state, attempting to decrease both the list and the waiting time for a corneal transplant.
