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The new oxofluoride Cu-7(TeO3)(6)F-2 has been synthesized by hydrothermal synthesis. It crystallizes in the triclinic system, space group P (1) over bar. The crystal structure constitutes a Cu-O framework with channels extending along [001] where the F- ions and the stereochernically active lone-pairs on Te4+ are located. From magnetic susceptibility, specific heat, and Raman scattering measurements we find evidence that the magnetic degrees of freedom of the Cu-O-Cu segments in Cu-7(TeO3)(6)F-2 lead to a mixed dimensionality with single Cu S = 1/2 moments wealdy coupled to spin-chain fragments. Due to the weaker coupling of the single moments, strong fluctuations exist at elevated temperatures, and long-range magnetic ordering evolves at comparably low temperatures (T-N = 15 K)., AuthorCount:7

Compounds within the solid solution (Co1-xNix)(3)Sb4O6F6 were prepared by the hydrothermal method. The compounds crystallize in the noncentrosymmetric cubic space group I (4) over bar 3m with unit cell parameters a = 8.176(1) angstrom for M = Co and a = 8.0778(1) angstrom for M = Ni. The crystal structure is made up by corner sharing [MO2F4] octahedra via the fluorine atoms. [Sb4O6E4] supertetrahedra (T2) consisting of four [SbO3E] groups (E being the stereo-chemically active lone-pair on Sb) that share O atoms with the [MO2F2](n) network. Magnetic ordering phenomena are observed with two characteristic temperatures, T-N and T*, in the range from 67 to 170 K, that evolve gradually with composition and collapse for M = Co (x = 0) to one transition. T-N is assigned to a transition into a long-range ordered antiferromagnetic phase, and T* marks a temperature in the range of 45 to 65 K where field cooled (FC) and zero field cooled (ZFC) susceptibility splits. The latter is tentatively attributed to a canting of the spin moments., AuthorCount:7

This study's objective is to evaluate the Open Architecture Warfare System Domain Model (OAWSDM) against time critical targets with specific focus on command, control, and communication processes. A functional analysis of the OAWSDM was conducted and synthesized to create the Open Architecture Time Critical Target Engagement Process Model (OATCTEPM). This model represents the notional engagement cycle of a Navy cruiser. Two scenarios were developed to exercise the system: a surprise assault from a number of personal watercraft and a saturation assault in which approximately fifty craft of varying sizes attack. Results from these scenarios were analyzed for system bottlenecks and recommendations were made to improve decision making processes and reduce engagement time. This study concludes that while the OAWSDM may offer no technical flaws in its design, it fails to factor in the role of the human in the decision making and engagement processes. In doing so it overlooks a key factor in the effectiveness of the architecture against surface TCT engagements., http://archive.org/details/ananalysisofopen109456933, NA

The effect of hydrostatic pressure on the superconductivity in LiFeAs is investigated up to 1.8GPa. The superconducting transition temperature, T-c, decreases linearly with pressure at a rate of 1.5K/GPa. The negative pressure coefficient of T-c and the high ambient pressure T-c indicate that LiFeAs is the high-pressure analogue of the isoelectronic SrFe2As2 and BaFe2As2. Copyright (C) EPLA, 2009

The synthesis and properties of LiFeAs, a high-Tc Fe-based superconducting stoichiometric compound, are reported. Single crystal x-ray studies reveal that it crystallizes in the tetragonal PbFCl type (P4/nmm) with a=3.7914(7) Å and c=6.364(2) Å. Unlike the known isoelectronic undoped intrinsic FeAs compounds, LiFeAs does not show any spin-density wave behavior but exhibits superconductivity at ambient pressures without chemical doping. It exhibits a respectable transition temperature of Tc=18 K with electronlike carriers and a very high critical field, Hc2(0)>80 T. LiFeAs appears to be the chemical equivalent of the infinite layered compound of the high-Tc cuprates.

This study's objective is to evaluate the Open Architecture Warfare System Domain Model (OAWSDM) against time critical targets with specific focus on command, control, and communication processes. A functional analysis of the OAWSDM was conducted and synthesized to create the Open Architecture Time Critical Target Engagement Process Model (OATCTEPM). This model represents the notional engagement cycle of a Navy cruiser. Two scenarios were developed to exercise the system: a surprise assault from a number of personal watercraft and a saturation assault in which approximately fifty craft of varying sizes attack. Results from these scenarios were analyzed for system bottlenecks and recommendations were made to improve decision making processes and reduce engagement time. This study concludes that while the OAWSDM may offer no technical flaws in its design, it fails to factor in the role of the human in the decision making and engagement processes. In doing so it overlooks a key factor in the effectiveness of the architecture against surface TCT engagements.