Suitability of commercially available laboratory cryogenic refrigerators to support shipboard electro-optical systems in the 10 - 77 Kelvin region

The primary development of cryogenically cooled infrared systems was accomplished by FLIR systems designed for airborne, passive night vision. Essential to the development of these FLIR systems was a family of closed cycle refrigerators which had to meet a limited envelope requirement, utilize a nonlubricated compressor module, and be light in weight. Closed cycle refrigerators accomplished the same cooling function, they use modified oil lubricated reciprocating compressors which are limited in their axis of orientation to an angle of approximately 15-20 degrees maximum from horizon

Crystallization and phase-separation in non-additive binary hard-sphere mixtures

We calculate for the first time the full phase-diagram of an asymmetric non-additive hard-sphere mixture. The non-additivity strongly affects the crystallization and the fluid-fluid phase-separation. The global topology of the phase-diagram is controlled by an effective size-ratio y_{eff}, while the fluid-solid coexistence scales with the depth of the effective potential well.Comment: 4 pages, 4 figures, to appear in Phys. Rev.

The structure of colloid-polymer mixtures

We investigate the structure of colloid-polymer mixtures by calculating the structure factors for the Asakura-Oosawa model in the PY approximation. We discuss the role of potential range, polymer concentration and polymer-polymer interactions on the colloid-colloid structure. Our results compare reasonably well with the recent experiments of Moussa\"{i}d et. al. for small wavenumber $k$, but we find that the Hansen-Verlet freezing criterion is violated when the liquid phase becomes marginal.Comment: 7 pages, 4 figures, to appear in EuroPhys. Let

New State Distribution and Host Records of North American Buprestidae (Coleoptera)

The following new state records are reported for buprestid species in the eastern United States: Agrilus egeniformis Champlain and Knull and Polyceta elata LeConte from Georgia, Agrilus defectus LeConte and Agrilus vittaticollis (Randall) from Minnesota and Agrilus paramasculinus Champlain and Knull from Michigan and Indiana. Chrysobothris shawnee Wellso and Manley and Chrysobothris rugosiceps Melsheimer are reported from red oak (Quercus rubra L.) and English oak (Quercus robur L.) for the first time, after being reared from naturally infested host material collected in Michigan, USA

Observational and theoretical studies of the evolving structure of baroclinic waves

Dynamical processes involved in comma cloud formation, and passive tracer evolution in a baroclinic wave are discussed. An analytical solution was obtained demonstrating the complex nongeostrophic flow pattern involved in the redistribution of low level constituents in a finite amplitude baroclinic wave, and in the formation of the typical humidity and cloud distributions in such a wave. Observational and theoretical studies of blocking weather patterns in middle latitude flows were studied. The differences in the energy and enstrophy cascades in blocking and nonblocking situations were shown. It was established that pronounced upscale flow of both of these quantities, from intermediate to planetary scales, occurs during blocking episodes. The upscale flux of enstrophy, in particular, suggests that the persistence of blocking periods may be due to reduced dissipation of the large scale circulation and therefore entail some above normal predictability

Investigation of microgravity effects on solidification phenomena of selected materials

A Get Away Special (GAS) experiment payload to investigate microgravity effects on solidification phenomena of selected experimental samples has been designed for flight. It is intended that the first flight of the assembly will (1) study the p-n junction characteristics for advancing semiconductor device applications, (2) study the effects of gravity-driven convection on the growth of HgCd crystals, (3) compare the textures of the sample which crystallizes in microgravity with those found in chondrite meteorites, and (4) modify glass optical characteristics through divalent oxygen exchange. The space flight experiment consists of many small furnaces. While the experiment payload is in the low gravity environment of orbital flight, the payload controller will sequentially activate the furnaces to heat samples to their melt state and then allow cooling to resolidification in a controlled fashion. The materials processed in the microgravity environment of space will be compared to the same materials processed on earth in a one-gravity environment. This paper discusses the design of all subassemblies (furnance, electronics, and power systems) in the experiment. A complete description of the experimental materials is also presented

Progress in three-particle scattering from LQCD

We present the status of our formalism for extracting three-particle scattering observables from lattice QCD (LQCD). The method relies on relating the discrete finite-volume spectrum of a quantum field theory with its scattering amplitudes. As the finite-volume spectrum can be directly determined in LQCD, this provides a method for determining scattering observables, and associated resonance properties, from the underlying theory. In a pair of papers published over the last two years, two of us have extended this approach to apply to relativistic three-particle scattering states. In this talk we summarize recent progress in checking and further extending this result. We describe an extension of the formalism to include systems in which two-to-three transitions can occur. We then present a check of the previously published formalism, in which we reproduce the known finite-volume energy shift of a three-particle bound state.Comment: 9 pages, 3 figures, proceedings for XIIth Quark Confinement and the Hadron Spectrum (CONF12

Three-particle systems with resonant subprocesses in a finite volume

In previous work, we have developed a relativistic, model-independent three-particle quantization condition, but only under the assumption that no poles are present in the two-particle K matrices that appear as scattering subprocesses. Here we lift this restriction, by deriving the quantization condition for identical scalar particles with a G-parity symmetry, in the case that the two-particle K matrix has a pole in the kinematic regime of interest. As in earlier work, our result involves intermediate infinite-volume quantities with no direct physical interpretation, and we show how these are related to the physical three-to-three scattering amplitude by integral equations. This work opens the door to study processes such as $a_2 \to \rho \pi \to \pi \pi \pi$, in which the $\rho$ is rigorously treated as a resonance state.Comment: 46 pages, 9 figures, JLAB-THY-18-2819, CERN-TH-2018-21

Facilitating Humanitarian Access to Pharmaceutical and Agricultural Innovation

Calls for intellectual property licensing strategies in the pharmaceutical and agricultural sectors that promote humanitarian access to product innovations for the benefit of the disadvantaged. Includes profiles of successful and promising strategies