Magnetic Properties of the Novel Low-Dimensional Cuprate Na5RbCu4(AsO4)4Cl2

The magnetic properties of a new compound, Na5RbCu4(AsO4)4Cl2 are reported. The material has a layered structure comprised of square Cu4O4 tetramers. The Cu ions are divalent and the system behaves as a low-dimensional S=1/2 antiferromagnet. Spin exchange in Na5RbCu4(AsO4)4Cl2 appears to be quasi-two-dimensional and non-frustrated. Measurements of the bulk magnetic susceptibility and heat capacity are consistent with low-dimensional magnetism. The compound has an interesting, low-entropy, magnetic transition at T = 17 K.Comment: 4 pages, 5 figure

Increased brightness of the lunar surface

Mechanisms causing increased brightness of lunar surface - solar flare proton and electron irradiatio

Mass Influxes and Protection in Europe: A Reflection on a Temporary Episode of an Enduring Problem

This article assesses Temporary Protection (TP) in Europe in response to refugee crises. In 2001 the European Union (EU) adopted a Directive for TP to provide a regional response to a mass influx. It was considered that TP offered a double-win: addressing protection needs of asylum seekers, while enabling states to maintain control based on the understanding that asylum seekers would return home after a short period of stay. The Directive has been endorsed in UNHCR Guidelines on ‘Temporary Protection or Stay Arrangements’ (2014). Notwithstanding, the analysis in this article indicates that TP was a strategy that failed: it did not give states control nor promote solidarity between them. Failure explains its absence in the responses to the 2015–16 crisis. However, national forms of TP have re-emerged signalling efforts to re-assert control in the face of an enduring problem

Quantitative study of molecular N_2 trapped in disordered GaN:O films

The structure of disordered GaN:O films grown by ion-assisted deposition is investigated using x-ray absorption near-edge spectroscopy and Raman spectroscopy. It is found that between 4 and 21 % of the nitrogen in the films is in the form of molecular N_2 that interacts only weakly with the surrounding matrix. The anion to cation ratio in the GaN:O host remains close to unity, and there is a close correlation between the N_2 fraction, the level of oxygen impurities, and the absence of short-range order in the GaN:O matrix.Comment: 5 pages, 3 figure

Escaping Nash inflation

Mean dynamics govern convergence to rational expectations equilibria of self-referential systems under least squares learning. We highlight escape dynamics that propel away from a rational expectations equilibrium under fixed-gain recursive learning schemes. These learning schemes discount past observations. In a model with a unique self-confirming equilibrium, we show that the destination of the escape dynamics is an outcome associated with government discovery of too strong a version of the natural rate hypothesis. That destination is not sustainable as a self-confirming equilibrium but is visited recurrently. The escape route dynamics cause recurrent outcomes close to the Ramsey (commitment) inflation rate in a model with an adaptive government. JEL Classification: E3, E52, E58

Spatial Equilibrium Analysis of the U.S. Hard Red Spring Wheat Industry under Alternative Transportation Rate Structures

Industrial Organization,

U.S./CANADA GRAIN HANDLING AND TRANSPORTATION SYSTEMS

The United States and Canada have developed very different grain handling and transportation systems (GHTSs) over the last several decades to compete for global and domestic markets in Canada and the United States under CUSTA. Because the grain industries in both countries face long distance hauls, GHTSs are critically important to their operations and to producer returns. There has been considerable pressure for change in Canada's grain handling and transportation sector. Some industry trends, such as the rationalization of elevators in the Prairies and investments in new high through-put facilities, are being driven by market and competitive forces. Changes in grain handling, reciprocal access to marketing functions, and elimination of rate caps may have a significant impact on cross-border grain flows. Canadian Transport announced reforms to improve the efficiency of its GHTS. Possible multi-level effects, created by the reform package, would affect the grain flow from Canada to the United States. The most significant reforms include 'port buying' by the Canadian Wheat Board, which would remove the Board's control over internal logistics and shipping, and replacement of the current maximum railway rate scale with a cap on annual railway revenues for grain shipments.Canadian Wheat Board (CWB), Grain Trade, Grain Transportation and Handling System (GHTS), Rail Rate, Railcar Allocation, Rationalization, Rate Cap, Reciprocal Access, Regulation, Reform Package., Crop Production/Industries,

Towards Zero-Waste Furniture Design

In traditional design, shapes are first conceived, and then fabricated. While this decoupling simplifies the design process, it can result in inefficient material usage, especially where off-cut pieces are hard to reuse. The designer, in absence of explicit feedback on material usage remains helpless to effectively adapt the design -- even though design variabilities exist. In this paper, we investigate {\em waste minimizing furniture design} wherein based on the current design, the user is presented with design variations that result in more effective usage of materials. Technically, we dynamically analyze material space layout to determine {\em which} parts to change and {\em how}, while maintaining original design intent specified in the form of design constraints. We evaluate the approach on simple and complex furniture design scenarios, and demonstrate effective material usage that is difficult, if not impossible, to achieve without computational support