Direct Observation of Long-Term Durability of Superconductivity in YBa2_2Cu3_3O7_7-Ag2_2O Composites

We report direct observation of long-term durability of superconductivity of several YBa$_2$Cu$_3$O$_7$-Ag$_2$O composites that were first prepared and studied almost 14 years ago [J. J. Lin {\it et al}., Jpn. J. Appl. Phys. {\bf 29}, 497 (1990)]. Remeasurements performed recently on both resistances and magnetizations indicate a sharp critical transition temperature at 91 K. We also find that such long-term environmental stability of high-temperature superconductivity can only be achieved in YBa$_2$Cu$_3$O$_7$ with Ag$_2$O addition, but not with pure Ag addition.Comment: to be published in Jpn. J. Appl. Phy

Radio Planetary Nebulae in the Small Magellanic Cloud

We present ten new radio continuum (RC) detections at catalogued planetary nebula (PN) positions in the Small Magellanic Cloud (SMC): SMPS6, LIN 41, LIN 142, SMP S13, SMP S14, SMP S16, J18, SMP S18, SMP S19 and SMP S22. Additionally, six SMC radio PNe previously detected, LIN 45, SMP S11, SMPS17, LIN321, LIN339 and SMPS24 are also investigated (re-observed) here making up a population of 16 radio detections of catalogued PNe in the SMC. These 16 radio detections represent ~15 % of the total catalogued PN population in the SMC. We show that six of these objects have characteristics that suggest that they are PN mimics: LIN 41, LIN 45, SMP S11, LIN 142, LIN 321 and LIN 339. We also present our results for the surface brightness - PN radius relation ({\Sigma}-D) of the SMC radio PN population. These are consistent with previous SMC and LMC PN measurements of the ({\Sigma}-D) relation.Comment: Accepted for publication in Astrophysics and Space Scienc

Generalized Supersymmetries and Composite Structure in M-Theory

We describe generalized D=11 Poincar\'{e} and conformal supersymmetries. The corresponding generalization of twistor and supertwistor framework is outlined with $OSp(1|64)$ superspinors describing BPS preons. The $\frac{k}{32}$ BPS states as composed out of $n=32 - k$ preons are introduced, and basic ideas concerning BPS preon dynamics is presented. The lecture is based on results obtained by J.A. de Azcarraga, I. Bandos, J.M. Izquierdo and the author$^1$.Comment: LaTeX, 7pages. Talk presented at the XVI-th Max Born Symposium ,,Supersymmetries and Quantum Symmetries `01" (21-25.09.2001, Karpacz, Poland) and International Nankai Symposium (8-11.10.2001, Tianjin, China). To be published in the Proceedings of Nankai Symposium, Ed. Ge Mo-Lin and J. Park, Int. J. Mod. Phys.

Controlling occupational cancers in Australia

Lin Fritschi, Renae C Fernandez, Deborah A Vallance, Terry J Slevin, Alison Reid, Timothy R Driscoll, Deborah C Glas

Investigation of phase separation within the generalized Lin-Taylor model for a binary liquid mixture of large hexagonal and small triangular particles

The generalized Lin-Taylor model defined on the hexagonal lattice is used to investigate the phase separation in an asymmetric binary liquid mixture consisting of large A (hexagons) and small B (triangles) particles. By considering interaction energies between A-A and A-B pairs of particles that occupy nearest-neighbour cells of the hexagonal lattice, we have derived an exact solution for the considered model system having established a mapping correspondence with the two-dimensional Ising model on its dual triangular lattice. Altogether, six different types of coexistence curves including those with reentrant miscibility regions (i.e. closed-loop coexistence curves) were found in dependence on the relative strength between both coupling constants.Comment: 8 pages, 4 figures, presented at 7th Liblice conference on the Statistical Mechanics of Liquids to be held in Lednice on June 11-16, 200