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Reactivity of phenyldi(2-thienyl) phosphine towards group 7 metal carbonyls: Carbon-phosphorus bond activation

Addition of phenyldi(2-thienyl) phosphine (PPhTh2) to [Re-2(CO)(10-n)(NCMe)(n)] (n = 1, 2) affords the substitution products [Re-2(CO)(10-n)(PhPTh2)(n)] (1, 2) together with small amounts of fac-[ClRe(CO)(3)(PPhTh2)(2)] (3) (n = 2). Reaction of [Re-2(CO)(10)] with PPhTh2 in refluxing xylene affords a mixture which includes 2, [Re-2(CO)(7)(PPhTh2)(mu-PPhTh)(mu-H)] (4), [Re-2(CO)(7)(PPhTh2)(mu-PPhTh

A Gradient-Enhanced Continuum Damage Model for Residually Stressed Fibre-Reinforced Materials at Finite Strains

The modelling of damage effects in materials constitutes a major challenge in various engineering-related disciplines. However, the assumption of purely local continuum damage formulations may lead to ill-posed boundary value problems and—with regard to numerical methods such as the finite element method—to mesh-dependent solutions, a vanishing localised damage zone upon mesh refinement, and hence

A toxicological and dermatological assessment of alkyl cyclic ketones when used as fragrance ingredients The RIFM Expert Panel

The alkyl cyclic ketone (ACK) fragrance ingredients are a diverse group of structures with Similar metabolic and toxicity profiles. ACK fragrance materials demonstrate low acute toxicity. Upon repeat dose testing, some adverse effects in biochemical and hematological parameters, and slightly increased liver and kidney weights were reported, primarily at high doses, resulting from adaptive effects.

Valence bond liquid phase in the honeycomb lattice material Li2RuO3

The honeycomb lattice material Li2RuO3 undergoes a dimerization of Ru4+ cations on cooling below 270 degrees C, where the magnetic susceptibility vanishes. We use density functional theory calculations to show that this reflects the formation of a valence bond crystal, with a strong structural bond disproportionation. On warming, x-ray diffraction shows that discrete threefold symmetry is regained

Hydrogen intercalation of graphene grown on 6H-SiC(0001)

Atomic hydrogen exposures on a monolayer graphene grown on the SiC(0001) surface are shown to result in hydrogen intercalation. The hydrogen intercalation induces a transformation of the monolayer graphene and the carbon buffer layer to bi-layer graphene without a buffer layer. The STM, LEED, and core-level photoelectron spectroscopy measurements reveal that hydrogen atoms can go underneath the gr

Quality indicators for woodwind reed material

For the generation of sound, some woodwind musical instruments, e.g. oboe, bassoon, clarinet and saxophone, are provided with mouthpieces made from reeds. These reeds are the culms of Arundo donax, a tall, cane-like perennial grass. A general problem is that the material is of varying quality, yet externally differences cannot be observed. Hence, large proportions of the prepared reeds are unusabl

IL-10-deficient B10.Q mice develop more severe collagen-induced arthritis, but are protected from arthritis induced with anti-type II collagen antibodies

IL-10 is a pleiotropic cytokine with stimulatory and inhibitory properties, and is thought to have a protective role in rheumatoid arthritis and collagen-induced arthritis (CIA). In this study, we investigated how IL-10 deficiency affects CIA and anti-collagen type II (CII) Ab-transferred arthritis in C57BL/10.Q (B10.Q) mice. The B10.Q.IL-10(-/-) mice had an 8-cM 129/Ola fragment around the IL-10

Urinary tract infections revisited.

Urinary tract infections (UTIs) remain a significant clinical problem, despite antibiotic treatment and surgical correction of reflux and malformations. Here we propose that novel molecular tools may be applied to modernize and individualize the diagnosis and therapy of UTI. Determinants of bacterial virulence and host resistance are relatively well understood at the molecular level, and technolog

Development of the ReaxFF Reactive Force Field for Mechanistic Studies of Catalytic Selective Oxidation Processes on BiMoOx

We have developed a new reactive force field, ReaxFF, for use in molecular dynamics (MD) simulations to investigate the structures and reactive dynamics of complex metal oxide catalysts. The parameters in ReaxFF are derived directly from QM and have been validated to provide reasonable accuracy for a wide variety of reactions. We report the use of ReaxFF to study the activation and conversion of p

The FERRUM project: Experimental f-values for 4p-5s transitions in Fe II

New measurements of radiative lifetimes of four 3d65s levelsin Fe II at about 10 eV are presented along with absolute oscillator strengths for twenty 4p-5s transitions involving the four levels. The experimental measurements are compared with two different sets oftheoretical calculations. The lines are of particular interest in the modeling of HLyalpha pumped fluorescence of Fe II in as

Linear Control and Estimation Using Operator Factorization

The filtering, prediction and smoothing problems as well as the linear quadratic control problems can very generally be formulated as operator equations using basic linear algebra. The equations are of Fredholm type II and difficult to solve directly. It is shown how the operator can be factorized into two Volterra operators using a matrix Riccati equation. Recursive solution of these triangular o

Polarized version of the CCFM equation for gluons

A derivation for a polarized CCFM evolution equation which is suitable to describe the scaling behavior of the unintegrated polarized gluon density is given. We discuss the properties of this polarized CCFM equation and compare it to the standard CCFM equation in the unpolarized case.