Crystal and Magnetic Structures in Layered, Transition Metal Dihalides and Trihalides

Materials composed of two dimensional layers bonded to one another through weak van der Waals interactions often exhibit strongly anisotropic behaviors and can be cleaved into very thin specimens and sometimes into monolayer crystals. Interest in such materials is driven by the study of low dimensional physics and the design of functional heterostructures. Binary compounds with the compositions MX2 and MX3 where M is a metal cation and X is a halogen anion often form such structures. Magnetism can be incorporated by choosing a transition metal with a partially filled d-shell for M, enabling ferroic responses for enhanced functionality. Here a brief overview of binary transition metal dihalides and trihalides is given, summarizing their crystallographic properties and long-range-ordered magnetic structures, focusing on those materials with layered crystal structures and partially filled d-shells required for combining low dimensionality and cleavability with magnetism.Comment: Accepted for publication Crystal

Subprime Education: For-Profit Colleges and the Problem with Title IV Federal Student Aid

Federal student-aid policy is designed with the goal of expanding access to higher education for all students. It has been enormously successful in achieving that goal. Yet, for many students, federal student aid has served only to burden them with oppressive student-debt obligations. These obligations are a particular problem with respect to the for-profit higher-education sector, which receives a large and ever-growing proportion of federal aid. This Note examines the interaction between federal student-aid policy and for-profit institutions, arguing that the noble goals of modern federal student-aid policy enable the very practices that lead to negative outcomes for many students by creating a lucrative market for subprime education. This Note analyzes a continuum of approaches to reducing the negative student outcomes caused by many for-profit institutions, concluding that the blame lies not with for-profit institutions but with federal student-aid policy. Ultimately, the modern federal student-aid regime requires regulators to choose between abetting negative student outcomes and reducing access to higher education. This dilemma can be avoided only by deemphasizing the student-oriented aid model in favor of an institution-centered model that is focused on reducing the price of education

Game Changer

Why the rapidly evolving landscape for clients requires creative new moves from lawyers and the profession

Augmented RIGS

The results of the Phase 2 Resonant Infrasonic Gauging System (RIGS) development program are presented. The program consisted of design, fabrication, and testing of an "augmented" RIGS concept. The RIGS is a gauging system capable of measuring propellant quantities in zero-g as well as under accelerated conditions. Except for hydrogen, it can be used to gauge virtually any propellant in liquid form, including cryogenics. The gage consists of a sensor unit which is attached to the propellant tank and an electronic control unit which may be positioned separately from the sensor. The control unit receives signals from the sensor as well as the propellant temperature measurement and the ullage gas pressure, and computes the propellant quantity in the tank