A comparison of equitable per diem policies for units deployed to U.S. bases

This thesis addresses the per diem funding requirements for units deployed to U.S. bases, Three alternative programs are compared: (1) the current Lodgings Plus policy, (2) AIRPAC's Smart TAD test, and (3) the DoD Task Force to Reengineer Travel recommendation to provide rations in kind. The impacts of these three alternatives on the Type Commanders, travelers, messing facilities, and MWR activities are examined to ensure that the missions can be accomplished while maintaining a high quality of life for the travelers. The primary areas evaluated are galley operations, missed meal reimbursement, and MWR compensation. Findings include that savings can be achieved by adopting the Rations In Kind policy, while still maintaining a high quality of life for the travelers. With the reduction in the DoN budget, some action is required to bridge the predicted shortfall between available fluiding and the budget needed to fully support the travel requirements. This study recommends that AIRPAC's Smart TAD test be modified and expanded to ensure that travel funds are available to support future operational commitments and readiness.http://archive.org/details/acomparisonofequ109457467U.S. Navy (U.S.N.) author

First Observation of Self-Amplified Spontaneous Emission in a Free-Electron Laser at 109 nm Wavelength

We present the first observation of Self-Amplified Spontaneous Emission (SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109 nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and the radiation characteristics, such as dependency on bunch charge, angular distribution, spectral width and intensity fluctuations all corroborate the existing models for SASE FELs.Comment: 6 pages including 6 figures; e-mail: [email protected]

Unravelling the Role of the Pentafluoroorthotellurate Group as a Ligand in Nickel Chemistry

The pentafluoroorthotellurate group (teflate, OTeF5) is able to form species, for which only the fluoride analogues are known. Despite nickel fluorides being widely investigated, nickel teflates have remained elusive for decades. By reaction of [NiCl4]2− and neat ClOTeF5, we have synthesized the homoleptic [Ni(OTeF5)4]2− anion, which presents a distorted tetrahedral structure, unlike the polymeric [NiF4]2−. This high‐spin complex has allowed the study of the electronic properties of the teflate group, which can be classified as a weak/medium‐field ligand, and therefore behaves as the fluoride analogue also in ligand‐field terms. The teflate ligands in [NEt4]2[Ni(OTeF5)4] are easily substituted, as shown by the formation of [Ni(NCMe)6][OTeF5]2 by dissolving it in acetonitrile. Nevertheless, careful reactions with other conventional ligands have enabled the crystallization of nickel teflate complexes with different coordination geometries, i.e. [NEt4]2[trans‐Ni(OEt2)2(OTeF5)4] or [NEt4][Ni(bpyMe2)(OTeF5)3]

Further Perspectives on the Teflate versus Fluoride Analogy: The Case of a Co(II) Pentafluoroorthotellurate Complex

The pentafluoroorthotellurate group (teflate, OTeF5 ) is considered as a bulky analogue ofbfluoride, yet its coordination behavior in transition-metal complexes is not fully understood. By reaction of [CoCl4 ]2– and neat ClOTeF5 , we have synthesized the first cobalt teflate complex, [Co(OTeF5 )4 ]2– , which exhibits moisture-resistant Co–OTeF5 bonds. Through a combined experimental and theoretical (DFT and NEVPT2) study, the properties and electronic structure of this species have been investigated. It exhibits a distorted tetrahedral structure around the cobalt center and can be described as a d7 system with a quartet (S = 3/2) ground state. A comparative bonding analysis of the (pseudo)tetrahedral [CoX4 ]2– anions (X = OTeF5 , F, Cl) revealed that the strength of the Co–X interaction is similar in the three cases, being the strongest in [Co(OTeF5 )4 ]2– . In addition, an analysis of the charge of the Co center reinforced the similar electron-withdrawing properties of the teflate and the fluoride ligands. Therefore, the [Co(OTeF5 )4 ]2– anion constitutes an analogue of the polymeric [CoF4 ]2– in terms of electronic properties, but with a monomeric structure.Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project-ID 387284271 – SFB 1349 and by the European Research Council (ERC) Project HighPotOx (grant agreement ID: 818862), as well as through the cluster of excellence “UniSysCat” funded by the DFG under Germany’s Excellence Strategy-EXC2008/1-390540038. We gratefully acknowledge the assistance of the Core Facility BioSupraMol supported by the DFG. A.P.-B. thanks the Alexander von Humboldt Foundation for a postdoctoral research fellowship, as well as the Department of Biology, Chemistry, Pharmacy of the Freie Universität Berlin for a Rising Star Junior Fellowship. J.M. acknowledges the Spanish MICINN (grant PID2021-122763NBI00) and the FICyT (grant IDI/2021/000054) for financial support, as well as Dr. Carlos Martín-Fernández and Prof. Ángel Martín Pendás for fruitful scientific discussions

Solvent-Dependent Reactivity of Fe(CO)5 under Superacidic and Oxidative Conditions

Herein, we report the solvent-dependent reactivity of Fe(CO)5 toward AsF5 in either anhydrous HF or liquid SO2. The reaction of Fe(CO)5 with the superacid HF/AsF5 leads to the protonation of the iron center and allows for the first-time structural characterization of [FeH(CO)5]+ in the solid state, representing one of the most acidic transition metal hydride complexes to ever be isolated and structurally characterized. In the aprotic but oxidation-stable solvent SO2, Fe(CO)5 is oxidized and dimerized to [Fe2(CO)10]2+, which is isoelectronic with well-known Mn2(CO)10. [Fe2(CO)10]2+ is the first structurally characterized example of a homoleptic dinuclear transition metal carbonyl cation. Together with Fe(CO)5 and [Fe(CO)5]+•, it is a rare example of an iron-centered triad from which the neutral, the radical cationic, and the dimerized dicationic species have been structurally and spectroscopically characterized. All characterizations are well supported by quantum chemical calculations. We also make the argument that the dimerization of [Fe(CO)5]+• is largely dependent on the employed solvent

The Power of High Precision Broadband Photometry: Tracing the Milky Way Density Profile with Blue Horizontal Branch stars in the Dark Energy Survey

Blue Horizontal Branch (BHB) stars, excellent distant tracers for probing the Milky Way's halo density profile, are distinguished in the $(g-r)_0$ vs $(i-z)_0$ color space from another class of stars, blue straggler stars (BSs). We develop a Bayesian mixture model to classify BHB stars using high-precision photometry data from the Dark Energy Survey Data Release 2 (DES DR2). We select $\sim2100$ highly-probable BHBs based on their $griz$ photometry and the associated uncertainties, and use these stars to map the stellar halo over the Galactocentric radial range $20 \lesssim R \lesssim 70$ kpc. After excluding known stellar overdensities, we find that the number density $n_\star$ of BHBs can be represented by a power law density profile $n_\star \propto R^{-\alpha}$ with an index of $\alpha=4.28_{-0.12}^{+0.13}$, consistent with existing literature values. In addition, we examine the impact of systematic errors and the spatial inhomogeneity on the fitted density profile. Our work demonstrates the effectiveness of high-precision $griz$ photometry in selecting BHB stars. The upcoming photometric survey from the Rubin Observatory, expected to reach depths 2-3 magnitudes greater than DES during its 10-year mission, will enable us to investigate the density profile of the Milky Way's halo out to the virial radius, unravelling the complex processes of formation and evolution in our Galaxy.Comment: 22 pages, 18 figures. Submitted AAS Journal. Comments Welcome Code used in this work can be found at: https://github.com/sazabi4/Yu2024_BHB

Mimicking the CO2 Bound State of the [Ni,Fe] CO Dehydrogenase

Complexes, where a doubly reduced CO22 amp; 8722; carbonite ligand is spanned between a nickel II centre and a transition metal II ion TM Fe, Co, Zn have been accessed. In non coordinating solvents the carbonite ligand exhibits a flexible coordination behaviour as observed by NMR spectroscopy and supported by DFT calculations. In particular the [Ni CO2 Fe] representative replicates the respective entity in an intermediate formed during CO2 conversion by the enzyme [Ni,Fe] CODH in many ways structure, spectroscopic properties, reactivity . Our investigations reveal that transition metal ions reduce the reduction potential of the carbonite unit but increase its tendency to undergo C amp; 8722;O bond cleavage. This may explain the choice of an iron II ion instead of a s or p block based Lewis acid as part of the active sit

Multiple Populations and a CH Star Found in the 300S Globular Cluster Stellar Stream

Milky Way globular clusters (GCs) display chemical enrichment in a phenomenon called multiple stellar populations (MSPs). While the enrichment mechanism is not fully understood, there is a correlation between a cluster’s mass and the fraction of enriched stars found therein. However, present-day GC masses are often smaller than their masses at the time of formation due to dynamical mass loss. In this work, we explore the relationship between mass and MSPs using the stellar stream 300S. We present the chemical abundances of eight red giant branch member stars in 300S with high-resolution spectroscopy fromMagellan/MIKE. We identify one enriched star characteristic of MSPs and no detectable metallicity dispersion, confirming that the progenitor of 300S was a globular cluster. The fraction of enriched stars (12.5%) observed in our 300S stars is less than the 50% of stars found enriched in Milky Way GCs of comparable present-day mass (∼ 104.5 M⊙). We calculate the mass of 300S’sprogenitor and compare it to the initial masses of intact GCs, finding that 300S aligns well with the trend between the system mass at formation and enrichment. 300S’s progenitor may straddle the critical mass threshold for the formation of MSPs and can therefore serve as a benchmark for the stellar enrichment process. Additionally, we identify a CH star, with high abundancesof s-process elements, probably accreted from a binary companion. The rarity of such binaries in intact GCs may imply stellar streams permit the survival of binaries that would otherwise be disrupted