More air force per dollar as applied to facilities contracts.

Thesis (M.B.A.)--Boston Universit

Synthesis and characterization of multiply metal-metal bonded complexes of molybdenum and tungsten

The reaction of W(,2)(mhp)(,4) (mhp = anion of 2-methyl-6-hydroxypyridine) with ClSiMe(,3) in refluxing pyridine gives the oxidative addition product W(,2)((mu)-H)((mu)-Cl)Cl(,4)(pyridine)(,4). The spectral characterization of this compound as well as the characterization and crystal structure of its 4-ethylpyridine analog have been accomplished. The structure determination of the 4-ethylpyridine complex implies that a tungsten-tungsten double bond is present in the dimer;Reaction of MoW(O(,2)CCMe(,3))(,4) with ClSiMe(,3) in the presence of excess trimethylphosphine affords the metal-metal quadruply bonded dimer MoWCl(,4)(PMe(,3))(,4). The crystalline heteronuclear dimer is isostructural with its dimolybdenum and ditungsten homonuclear analogs and possesses intermediate structural features. Its (\u2731)P NMR consists of two equal-intensity resonances each split into a 1:2:1 triplet by a P-P\u27 coupling of 24,4 Hz across the metal-metal quadruple bond;A preparative reaction similar to that used for formation of thedimer, but using a reduced quantity of PMe(,3), yields the hetero-nuclear tetramer Mo(,2)W(,2)Cl(,8)(PMe(,3))(,4). The tetramer possesses arectangular arrangement of metal atoms and can be viewed as acycloaddition product of two dimer units. It is structurally akin torectangular homonuclear tetramers of molybdenum and tungsten,but exhibits certain anomalous bonding features compared tothe homonuclear analogs. From a (\u2731)P NMR spectrum ofMo(,2)W(,2)Cl(,8)(PBu(,3)(\u27n))(,4), it is possible to distinguish two tetrameric;isomers differing only by the arrangement of the metal atoms around the rectangle;(\u271)DOE Report IS-T-1044. This work was performed under ContractW-7405-eng-82 with the Department of Energy

The International Classification of Functioning Disability and Health Framework (ICF):a new approach to enhance sport and physical activity participation among people with disabilities in Scotland

This research provides a pilot study of the International Classification of Functioning Disability and Health Framework (ICF) involving persons with disabilities (PWD) with and without lived experience of sport participation in Scotland. National surveys in Scotland provide limited information on the nature of individual disability restricting the understanding of the relationship between disability and sport and physical activity participation. The ICF is a framework that aims to describe and classify functioning and thus can be used as a tool to provide a more detailed description of impairment for PWDs beyond their clinical condition. This knowledge has the potential to enhance the development of policies to increase the participation levels in this group. The ICF has also been used to inform the current IPC classification system at a competitive and elite level. As part of a larger study, 450 participants aged between 12 and 70 years completed an online questionnaire examining attitudes to, and participation in, sport and physical activity as well as completing the structural and functional components of the ICF. Subsequently, 18 people participated in focus groups aged between 13 and 61 years. The focus groups examined four meta-theme areas: physical, social, psychological, and sport-specific factors. The results confirm that the ICF provided a more detailed indicator of the key impairments that could have an impact on sport and physical activity participation. There was a clear lack of awareness of the links between the ICF and the classification system for competitive parasport. We concluded that a modified ICF-based assessment tool, incorporating social and environmental factors, has the potential to predict the likelihood of participation and offers a more comprehensive picture of both individual and national disability characteristics. This allows for the development of targeted policies and strategies to assist those with a disability to participate in sport. The overall framework presents a shift in thinking, in policy terms, for those in public health and in sport governance and delivery. The significance of this work is especially concerned with public health and wellbeing and sport development policy as pathways from recreational sport user to elite athlete parasport classification and performance

Impact of Small Group Size on Neighborhood Influences in Multilevel Models

Objective: Although there is a growing body of literature on sample size in multilevel or hierarchical modeling, few studies have examined the impact of group sizeMultilevel, Neighborhood, Body Weight, Obesity, Sample Size

Exploring Halo Substructure with Giant Stars: The Dynamics and Metallicity of the Dwarf Spheroidal in Bootes

We report the results of a spectroscopic study of the Bootes (Boo) dwarf spheroidal (dSph) galaxy carried out with the WIYN telescope and the Hydra multifiber spectrograph. Radial velocities have been measured for 58 Boo candidate stars selected to have magnitudes and colors consistent with its red and asymptotic giant branches. Within the 13' half-light radius, seven members of Boo yield a systemic velocity of V_r=95.6+-3.4 km/s and a velocity dispersion of 6.6+-2.3 km/s. This implies a mass on the order of 1 x 10^7 M_sun, similar to the inferred masses of other Galactic dSphs. Adopting a total Boo luminosity of L=1.8 x 10^4 L_sun to 8.6 x 10^4 L_sun implies M/L ~ 610 to 130, making Boo, the most distorted known Milky Way dwarf galaxy, potentially also the darkest. From the spectra of Boo member stars we estimate its metallicity to be [Fe/H] ~ -2.5, which would make it the most metal poor dSph known to date.Comment: Accepted for publication in ApJ Letter

A Deep Proper-Motion Survey in Kapteyn Selected Areas: I. Survey Description and First Results for Stars in the Tidal Tail of Sagittarius and in the Monoceros Ring

We describe a high-precision, deep (to V ~ 19-21) absolute proper-motion survey that samples ~50 lines of sight in the Kapteyn Selected Areas along declination zones -15, 0 and 15 degrees. In many fields the astrometric baseline reaches nearly a century. We demonstrate that these data provide typical per star precisions between ~ 1 and 3 mas/yr to the above magnitude limits, with the absolute reference frame established by numerous extragalactic sources in each survey field. Combined with existing and ongoing photometric and radial velocity surveys in these fields, these astrometric data will enable, among other things, accurate, detailed dynamical modeling of satellite interactions with our Galaxy. In this contribution we describe the astrometric part of our survey and show preliminary results along the trailing tail of the Sagittarius dwarf galaxy, and in the Monoceros ring region.Comment: Accepter for publication in the Astronomical Journa

The ferrimagnetic compounds CoM[M'(EDTA)]2.4H2O (M,M'=Co,Ni): Magnetic characterization of CoCo[Ni(EDTA)]2.4H2O

Under the terms of the Creative Commons Attribution (CC BY) license to their work.We report on the magnetic properties of the ordered bimetallic compound CoCo(NiEDTA)2⋅4H2O (abbreviated as [CoCoNi]). The structure consists of ordered bimetallic layers formed by alternating octahedral sites of Co and Ni(II); tetrahedral Co sites connect different Co‐Ni layers. We discuss the low‐dimensional ferrimagnetic behavior of this compound in terms of a model that assumes three spin sublattices exchange coupled by an Ising interaction.This work was supported by the Comision Interministerial en Ciencia y Tecnologia (Grant No. PB 85-OI06-C02-02), the Iustitucio Valenciana d'Estudis i Investigació, and the National Science Foundation (Grant No. DMR-8515224). F. S. andP. G. R. thank the Spanish Ministerio de Educacion y Ciencia for a predoctoral and postdoctoral fellowship, respectively.Peer Reviewe

Bimetallic derivatives of the [M(en)3]3+ ion (M=Cr and Co): A series of compounds with unusual magnetic and structural properties (abstract)

Under the terms of the Creative Commons Attribution (CC BY) license to their work.The crystal structure and magnetic susceptibility of a series of [M(en)3]3+ (M=Cr or Co) derivatives are described. In particular, the crystalline structures of (1) [Cr(en) 3]3[FeCl6]Cl6·H2O, (2) [Co(en)3]3[FeCl6]Cl6· H2O, and (3) [Cr(en)3][FeCl6]·11H 2O are reported. Structural data, in Å, for these compounds are as follows: (1) space group R3, a=15.447(4), c=21.060(6), Z=3; (2) space group R3, a=15.346(3), c=20.880(5), Z=3; (3) space group P3c1, a=11.654(3), c=15.508(4), Z=2. The main structural feature of the first two isomorphous materials is that they consist of a three-dimensional network of triangular antiprisms formed by the [M(en)3]3+ (M=Cr or Co) ions and connected with each other by sharing corners. An [FeCl 6]3- ion is placed at the center of each antiprism. Compound (3) contains a sc arrangement of [Cr(en)3] 3+ and [FeCl6]3- octahedra. In addition, the magnetic susceptibilities of the above-mentioned isomorphous compounds and of [M(en)3][FeCl6] (M=Cr and Co) and [Cr(en)3][InCl6] are reported. While [Cr(en) 3]3[FeCl6]Cl6·H2O orders as a ferrimagnet at 0.91 K, [Cr(en)3][FeCl6] exhibits antiferromagnetic properties with Tc=2.26 K, a temperature rather similar to the antiferromagnetic ordering temperature of [Co(en) 3][FeCl6].Peer Reviewe