Pressure effects on superconducting properties of single-crystalline Co doped NaFeAs

Resistivity and magnetic susceptibility measurements under external pressure were performed on single-crystals NaFe1-xCoxAs (x=0, 0.01, 0.028, 0.075, 0.109). The maximum Tc enhanced by pressure in both underdoped and optimally doped NaFe1-xCoxAs is the same, as high as 31 K. The overdoped sample with x = 0.075 also shows a positive pressure effect on Tc, and an enhancement of Tc by 13 K is achieved under pressure of 2.3 GPa. All the superconducting samples show large positive pressure coefficient on superconductivity, being different from Ba(Fe1-xCox)2As2. However, the superconductivity cannot be induced by pressure in heavily overdoped non-superconducting NaFe0.891Co0.109As. These results provide evidence for that the electronic structure is much different between superconducting and heavily overdoped non-superconducting NaFe1-xCoxAs, being consistent with the observation by angle-resolved photoemission spectroscopy.Comment: 6 pages, 6 figure

Governance issues in developing and implementing offsets for water management benefits: Can preliminary evaluation guide implementation effectiveness?

This article explores governance issues in developing innovative pollutant offset programs by focusing on a case study being piloted at the Gisborne Recycled Water Plant in Jacksons Creek, a rural sub-catchment of the Maribyrnong River north of Melbourne, Australia. The paper offers preliminary lessons from the ongoing design and anticipated challenges facing this innovative program based on reflections from the literature and project progress to-date. This case exemplifies a form of adaptive governance – an approach well suited to achieving broad sustainability objectives – and for which an early assessment is both appropriate and opportune. Adaptive governance is characterized by governmental collaboration with civil society groups, social learning through public participation, and experimentation leading to more flexible policy outcomes. Early assessment affords the possibility of mid-course corrections, drawing on experience acquired elsewhere. We contend that the approach being developed in Victoria through this pilot program has implications beyond the use of recycled wastewater for achieving various social objectives. It may also contribute to the development of an expansive water quality offset framework applicable to point source discharges, nonpoint source pollution, and sewerage overspills. Moreover, the approach can be applied to design of offset systems elsewhere – with appropriate economic savings and effective application to multiple water quality challenges if potential problems are discerned early

Evaluation of hydrogeologic properties of the Barbados accretionary prism: a synthesis of Leg 156 results

In situ and laboratory studies of permeability, conducted by Ocean Drilling Program scientists from Leg 156, provide constraints on parameters controlling the hydrogeologic system in the Barbados accretionary prism. Results from these studies indicate that core-scale and formation-scale permeability values differ by at least several orders of magnitude and are dependent on pore-fluid pressure and effective stress conditions. Direct measurement from packer experiments and indirect evidence from consolidation tests suggest that pore-fluid pressures are commonly above hydrostatic values and approach lithostatic values within the décollement zone. Permeability and fluid pressure conditions in the Barbados accretionary prism reflect the complexity of the hydrogeologic system of such an active tectonic environment

Radio-Continuum study of the Nearby Sculptor Group Galaxies. Part 1: NGC 300 at lambda = 20 cm

A series of new radio-continuum (lambda=20 cm) mosaic images focused on the NGC 300 galactic system were produced using archived observational data from the VLA and/or ATCA. These new images are both very sensitive (rms=60 microJy) and feature high angular resolution (<10"). The most prominent new feature is the galaxy's extended radio-continuum emission, which does not match its optical appearance. Using these newly created images a number of previously unidentified discrete sources have been discovered. Furthermore, we demonstrate that a joint deconvolution approach to imaging this complete data-set is inferior when compared to an immerge approach.Comment: 13 pages, 12 figures, accepted to APSS, new version to correct the missing reference

Interplay of Superconductivity and Fermi-Liquid Transport in Rh-Doped CaFe2As2 with Lattice-Collapse Transition

Ca(Fe$_{1-x}$Rh$_x$)$_2$As$_2$ undergoes successive phase transitions with increasing Rh doping in the $T$ $=$ 0 limit. The antiferromagnetic-metal phase with orthorhombic structure at 0.00 $\le$ $x$ $\le$ 0.020 is driven to a superconducting phase with uncollapsed-tetragonal (ucT) structure at 0.020 $\le$ $x$ $\le$ 0.024; a non-superconducting collapsed-tetragonal (cT) phase takes over at $x$ $\geq$ 0.024. The breakdown of Fermi-liquid transport is observed in the ucT phase above $T_{\rm c}$. In the adjacent cT phase, Fermi-liquid transport is restored along with a disappearance of superconductivity. This interplay of superconductivity and Fermi-liquid transport suggests the essential role of magnetic fluctuations in the emergence of superconductivity in doped CaFe$_2$As$_2$.Comment: 11 pages, 4 figure

Striped antiferromagnetic order and electronic properties of stoichiometric LiFeAs from first-principles calculations

We investigate the structural, electronic, and magnetic properties of stoichiometric LiFeAs by using state-of-the-arts first-principles method. We find the magnetic ground-state by comparing the total energies among all the possible magnetic orders. Our calculated internal positions of Li and As are in good agreement with experiment. Our results show that stoichiometric LiFeAs has almost the same striped antiferromagnetic spin order as other FeAs-based parent compounds and tetragonal FeSe do, and the experimental fact that no magnetic phase transition has been observed at finite temperature is attributed to the tiny inter-layer spin coupling

England’s Electronic Prescription Service: Infrastructure in an Institutional Setting

We describe the development of the Electronic Prescription Service (EPS), the solution for the electronic transmission of prescriptions adopted by the English NHS for primary care. The chapter is based on both an analysis of data collected as part of a nationally commissioned evaluation of EPS, and on reports of contemporary developments in the service. Drawing on the notion of an installed infrastructural base, we illustrate how EPS has been assembled within a rich institutional and organizational context including causal pasts, contemporary practices and policy visions. This process of assembly is traced using three perspectives; as the realization and negotiation of constraints found in the wider NHS context, as a response to inertia arising from limited resources and weak incentive structures, and as a purposive fidelity to the existing institutional cultures of the NHS. The chapter concludes by reflecting on the significance of this analysis for notions of an installed base

Toward an improved wall treatment for multiple-correction k-exact schemes

Improved wall boundary treatments are investigated for a family of high-order Godunovtype finite volume schemes based on k-exact polynomial reconstructions in each cell of the primitive variables, via a successive corrections procedure. We focus more particularly on the 1-exact and 2-exact schemes which offer a good trade-off between accuracy and computational efficiency. In both cases, the reconstruction stencil needs to be extended to the boundaries. Additionally, information about wall curvature has to be taken into account, which is done by using a surface model based on bicubic Bézier patches for the walls. The performance of the proposed models is presented for two compressible cases, namely the inviscid flow past a Gaussian bump and the viscous axisymmetric Couette flow

Monitoring coral reefs within the Reef 2050 Integrated Monitoring and Reporting Program: final report of the coral reef expert group

[Extract] The Coral Reef Expert Group (CREG) was one of eight expert groups, which all followed a prescribed process to recommend a design for their thematic component. The tasks of the expert groups included: • Synopsis of the theme, to include discussion on current state, primary drivers, pressures and responses using DPSIR framework. • Review of all current monitoring and modelling activities relevant to the expert group theme. • Identify candidate indicators that can be monitored and would provide information about trend, status or forecasting of value or the system. • Evaluation of the adequacy and confidence of current monitoring and modelling of candidate indicators, determined by their ability to meet the objectives of the RIMReP and management needs provided by the Authority. • Identification and discussion of gaps and opportunities in current monitoring and modelling of such indicators. • Evaluation of new monitoring technologies for their potential to increase efficiency or statistical power and their compatibility with long-term datasets. • Recommendations for monitoring design including consideration of primary indicators, continuity of data sets, how the design addresses management needs, modification to existing programs, costing and transition strategies.An accessible copy of this report is not yet available from this repository, please contact [email protected] for more information