Impurity Diffusion as a Possible Metal Chronometer for Pre-Detonation Nuclear Forensics

The ability to determine the age of seized nuclear material—that is, the time that has passed since it was formed— would provide crucial data to be used in its investigation. This paper reviews the methods and mathematical reasoning behind the use of diffusion theory, as previously applied to analysis of metals in ancient artifacts and other objects, to modern investigations in nuclear science. We here examine the time-dependent processes of diffusion, including grain boundary diffusion and discontinuous precipitation, and we assess the utility of examining the profiles of impurity and alloying element concentrations for use as a tool in pre-detonation nuclear forensics

‘You don't need a degree to get a coaching job’:investigating the employability of sports coaching degree students

Though highly popular, degree-level sports coaching qualifications are in their infancy, and it remains that ‘an individual intending to become an accredited coaching practitioner can only do so by undertaking their sport's national governing body (NGB) coaching award(s)’ [Nelson et al., 2006, p. 254. Formal, nonformal and informal coach learning: A holistic conceptualisation. International Journal of Sports Science & Coaching, 1(3), 247–259]. Consequently, little is known about the development of HE sports coaching students’ employability. This study critically investigates sports coaching students’ degree-study motives, development of employability skills and perceptions of career prospects as graduates. Survey data and follow-up interviews from two U.K. post-92 universities reveal tensions between liberal and vocational philosophies of university education and concerns about the graduate labour market. Critical incidents and missed opportunities in students’ development of key skills for coaching during and outside of university are also discussed

Adaptivity and a posteriori error control for bifurcation problems II: Incompressible fluid flow in open systems with Z_2 symmetry

In this article we consider the a posteriori error estimation and adaptive mesh refinement of discontinuous Galerkin finite element approximations of the bifurcation problem associated with the steady incompressible Navier-Stokes equations. Particular attention is given to the reliable error estimation of the critical Reynolds number at which a steady pitchfork or Hopf bifurcation occurs when the underlying physical system possesses reflectional or Z_2 symmetry. Here, computable a posteriori error bounds are derived based on employing the generalization of the standard Dual-Weighted-Residual approach, originally developed for the estimation of target functionals of the solution, to bifurcation problems. Numerical experiments highlighting the practical performance of the proposed a posteriori error indicator on adaptively refined computational meshes are presented

[(Z)-O-Isopropyl N-(m-tol­yl)thio­carbamato-κS](tricyclo­hexyl­phosphine-κP)gold(I)

The Au atom in the title compound, [Au(C11H14NOS)(C18H33P)], is coordinated within an S,P-donor set that defines a slightly distorted linear geometry [S—Au—P = 174.73 (3)°], with the distortion due in part to a close intra­molecular Au⋯O contact [3.060 (3) Å]. In the crystal structure, mol­ecules are arranged in layers in the bc plane with the primary connections between the arrays being of the type C—H⋯π

[O-Ethyl (Z)-N-(2-chloro­phen­yl)thio­carbamato-κS](tricyclo­hexyl­phosphine-κP)gold(I)

The title compound, [Au(C9H9ClNOS)(C18H33P)], features a slightly distorted linear coordination geometry for the Au atom defined by a S,P-donor set [S—Au—P = 177.62 (5)°]. The distortion is ascribed to the close approach of the O atom, which forms an intra­molecular contact of 2.970 (5) Å. Disorder was found in the structure with two positions of equal weight being resolved for the C atoms comprising the eth­oxy group

[(Z)-O-Ethyl N-(4-chloro­phen­yl)thio­carbamato-κS](triphenyl­phosphine-κP)gold(I) dichloro­methane hemisolvate

The AuI atom in the title compound, [Au(C9H9ClNOS)(C18H15P)]·0.5CH2Cl2, exists within a slightly distorted linear geometry defined by an S,P donor set [S—Au—P angle = 178.01 (4)°]; a close intra­molecular Au⋯O contact [2.964 (4) Å] also occurs. In the crystal structure, mol­ecules are linked into supra­molecular chains propagating along [010] by C—H⋯N, C—H⋯S and C—H⋯π inter­actions. The solvent mol­ecule is disordered about a twofold rotation axis

[(Z)-Ethyl N-isopropyl­thio­carbamato-κS](tricyclo­hexyl­phosphine-κP)gold(I)

The AuI atom in the title compound, [Au(C6H12NOS)(C18H33P)], is coordinated within a S,P-donor set that defines a slightly distorted linear geometry [S—Au—P angle = 173.44 (5)°], with the distortion due in part to a close intra­molecular Au⋯O contact [3.023 (4) Å]. The N-bound isopropyl group is disordered over two orientations in a 0.618 (15):0.382 (15) ratio

[μ-1,2-Bis(diphenyl­phosphino)methane-κ2 P:P′]bis­{[(Z)-O-ethyl N-(4-nitro­phen­yl)thio­carbamato-κS]gold(I)}

Each gold atom in the binuclear title compound, [Au2(C9H9N2O3S)2(C25H22P2)], is coordinated within an S,P-donor set that defines a slightly distorted linear geometry [S—Au—P angles = 172.77 (6) and 173.84 (6)°], with the distortion due in part to a close intra­molecular Au⋯O contact [2.968 (11) and 2.963 (4) Å]. The mol­ecule adopts a U-shaped conformation allowing for the formation of an aurophilic Au⋯Au inter­action [3.2320 (5) Å]. Mol­ecules are consolidated in the crystal structure by C—H⋯π inter­actions. Disorder was noted for one of the eth­oxy groups with two orientations being resolved in a 0.679 (16):0.321 (16) ratio

[(Z)-O-Methyl N-(3-chloro­phen­yl)thio­carbamato-κS](triphenyl­phosphine-κP)gold(I)

The Au atom in the title compound, [Au(C8H7ClNOS)(C18H15P)], exists within a slightly distorted linear geometry defined by an S,P-donor set [S—Au—P angle = 174.61 (4)°], with the distortion related to a short intra­molecular Au⋯O contact [2.988 (3) Å]. In the crystal structure, mol­ecules are arranged into supra­molecular chains along the b axis by C—H⋯π inter­actions