Surface mineral crusts: A priority target in search for life on Mars

Mineral crusts are strong candidates in the search for evidence of life during planetary exploration, and should be an important target for examination in impact craters. Crusts in the Haughton crater readily yield a biological signature

Quantum Communication Through an Unmodulated Spin Chain

We propose a scheme for using an unmodulated and unmeasured spin-chain as a channel for short distance quantum communications. The state to be transmitted is placed on one spin of the chain and received later on a distant spin with some fidelity. We first obtain simple expressions for the fidelity of quantum state transfer and the amount of entanglement sharable between any two sites of an arbitrary Heisenberg ferromagnet using our scheme. We then apply this to the realizable case of an open ended chain with nearest neighbor interactions. The fidelity of quantum state transfer is obtained as an inverse discrete cosine transform and as a Bessel function series. We find that in a reasonable time, a qubit can be directly transmitted with better than classical fidelity across the full length of chains of up to 80 spins. Moreover, the spin-chain channel allows distillable entanglement to be shared over arbitrarily large distances.Comment: Much improved versio

Nitrogen and phosphorus compound fertilisers

Nitrogen and phosphorus are two vitally important elements for plant growth which are deficient in most soils throughout Western Australia\u27s agricultural areas. Both nitrogen and phosphorus can also be applied in appropriate compound fertilisers which can be drilled with the seed, thus making their handling much easier. However, excessively high rates can depress plant emergence and may lower crop yields

Magnetic properties of a novel Pr Fe Ti phase

In a systematic study of the (Pr1−xTix)Fe5 alloy series, the (Pr0.65Ti0.35)Fe5 alloy has been found to have a dominant phase with either the rhombohedral Th2Zn17 structure or the newly discovered Nd2(Fe,Ti)19 (S. J. Collocott, R. K. Day, J. B. Dunlop, and R. L. Davis, in Proceedings of the Seventh International Symposium on Magnetic Anisotropy and Coercivity in R‐T Alloys, Canberra, July 1992, p. 437) structure, depending on the annealing procedure. Powder‐x‐ray‐diffraction patterns and scanning electron microscopy show that the sample annealed at a temperature of 850 °C followed by 1000 °C has the 2:17 structure whereas annealing at 1000 °C directly leads to the new 2:19 structure. Energy‐dispersive x‐ray analysis yields Pr:Fe:Ti ratios of 10.7:86.2:3.1 for the Pr2(Fe,Ti)17 phase and 9.2:85.9:4.9 for the Pr2(Fe,Ti)19 phase. 57 Fe Mössbauer spectroscopy (at 295 K) gives values for the average 57 Fe hyperfine field of 15.7 T for the 2:17 phase and 17.5 T for the 2:19 phase, respectively

Decide : how much superphosphate

* A 400 per cent increase in ihe price of superphosphate has reduced the economic optimum rates of super for crops and pastures in 1975. * Many factors, both biological and economic, must be taken into account in determining the rate of superphosphate to apply. • DECIDE, a model developed by CSIRO and the Department of Agriculture, provides a formal system in which all these factors can be considered. • DECIDE is based on the results of all research on superphosphate carried out in Western Australia. However, each farmer\u27s own knowledge of his farm, the soils, crops and animals is used to adapt the experimental results to get the best, easily available estimate of how much super should be applied to give maximum returns on superphosphate expenditure. Information about DECIDE is available from all District Offices of the Department of Agriculture

Magnetic properties of Gd(Fe1−xCox)9Ti2 alloys

Four samples of Gd(Fe1−xCox)9Ti2 with x=0.0, 0.1, 0.2, and 0.3 were prepared by conventional arc melting followed by annealing at 1000 °C for 3 days. Powder‐x‐ray‐diffraction patterns of these samples show that all of the samples have a dominant phase with the tetragonal CeMn6Ni5 structure. Traces of TiFe2 are also present. 57 Fe Mössbauer spectra have been collected at 80 and 295 K. X‐ray‐diffraction patterns and Mössbauer spectra on magnetically aligned samples indicate that the easy axis of magnetization is the crystallographic c axis. The Curie temperature increases monotonically with increasing cobalt concentration. The average hyperfine field at 80 K reaches a maximum of 26.8(5) T for x≊0.2

Global Alfven Eigenmodes in the H-1 heliac

Recent upgrades in H-1 power supplies have enabled the operation of the H-1 experiment at higher heating powers than previously attainable. A heating power scan in mixed hydrogen/helium plasmas reveals a change in mode activity with increasing heating power. At low power (<50 kW) modes with beta-induced Alfven eigenmode (BAE) frequency scaling are observed. At higher power modes consistent with an analysis of nonconventional Global Alfven Eigenmodes (GAEs) are observed, the subject of this work. We have computed the mode continuum, and identified GAE structures using the ideal MHD solver CKA and the gyrokinetic code EUTERPE. An analytic model for ICRH-heated minority ions is used to estimate the fast ion temperature from the hydrogen species. Linear growth rate scans using a local flux surface stability calculation, LGRO, are performed. These studies demonstrate growth from circulating particles whose speed is significantly less than the Alfven speed, and are resonant with the mode through harmonics of the Fourier decomposition of the strongly-shaped heliac magnetic field. They reveal drive is possible with a small, hot energetic tail of the hydrogen species. Local linear growth rate scans are also complemented with global calculations from CKA and EUTERPE. These qualitatively confirm the findings from the LGRO study, and show that the inclusion of finite Larmor radius effects can reduce the growth rate by a factor of three, but do not affect marginal stability. Finally, a study of damping of the global mode with the thermal plasma is conducted, computing continuum, and the damping arising from parallel electric fields. We find that continuum damping is of order 0.1% for the configuration studied. The inclusion of resistivity lifts the damping to 19%. Such large damping is consistent with experimental observations that in absence of drive the mode decays rapidly (~0.1 ms).Comment: 18 pages, 15 figures, submitted 07/04/2017 to Plasma Physics and Controlled Fusio