Structural and elastic characterization of Cu-implanted SiO₂ films on Si(100) substrates

Cu-implanted SiO₂ films on Si(100) have been studied and compared to unimplanted SiO₂ on Si(100) using x-ray methods, transmission electron microscopy, Rutherford backscattering, and Brillouin spectroscopy. The x-ray results indicate the preferred orientation of Cu {111} planes parallel to the Si substrate surface without any directional orientation for Cu-implanted SiO₂∕Si(100) and for Cu-implanted and annealedSiO₂∕Si(100). In the latter case, transmission electron microscopy reveals the presence of spherical nanocrystallites with an average size of ∼2.5 nm. Rutherford backscattering shows that these crystallites (and the Cu in the as-implanted film) are largely confined to depths of 0.4−1.2 μm below the film surface. Brillouin spectra contain peaks due to surface, film-guided and bulk acoustic modes. Surface (longitudinal) acoustic wave velocities for the implanted films were ∼7% lower (∼2% higher) than for unimplanted SiO₂∕Si(100). Elastic constants were estimated from the acoustic wave velocities and film densities. C₁₁ (C₄₄) for the implanted films was ∼10% higher (lower) than that for the unimplanted film. The differences in acoustic velocities and elastic moduli are ascribed to implantation-induced compaction and/or the presence of Cu in the SiO₂ film.B.J. and M.C.R. are grateful for financial support from the Australian Synchrotron Research Program, funded by the Commonwealth of Australia. M.C.R. would also like to thank the Australian Research Council for their financial support. The financial support of the Natural Sciences and Engineering Research Council of Canada NSERC is gratefully acknowledged by G.T.A. and J.S

Exploring aspects of significance when arranging dog visits to home-dwelling patients: An action research approach

Municipalities have been encouraged to collaborate with volunteers to facilitate social and cultural activities for patients. Dog visits have been primarily arranged as a group activity in nursing homes. The aim of the present study was to pilot a dog visit program for home-dwelling patients delivered through a collaboration between nurses and volunteers, and to explore aspects of significance when arranging such visits. The project used an action research approach. The action was the implementation of regular dog visits to home-dwelling patients for 6 months, through collaboration between nurses and volunteers. The empirical investigation included respective focus group interviews with nurses and volunteers. Transcribed data were analyzed thematically. Standards for Reporting Qualitative Research guidelines were followed. Influence of motivation, vulnerable relationships, and the perception that various factors contributed to a ‘comprehensive puzzle’ were aspects of significance when arranging dog visits to home-dwelling patients. One crucial factor in the conduction of the dog visits was having coordinators for both the nurses and volunteers. Future dog visits should emphasize thorough mapping of patients and equipages, and appropriate information flow through collaboration between coordinators for nurses and volunteers.publishedVersionPaid open acces

Tilstanden i sjøområdene ved Grimstad før start av biologisk renseanlegg på Groos

I 1995 ble Groosefjorden undersøkt for å dokumentere tilstanden før igangsetting av nytt biologisk renseanlegg. Det ble også gjort undersøkelser i andre kystområder i Grimstad kommune for å vurdere tilstanden. Undersøkelsene omfattet vannkjemiske målinger (oksygen, næringssalter, temperatur og saltholdighet), bløtbunnprøver, hardbunnundersøkelser (strandsone og dykk) samt undersøkelse av fiskeforekomster. Undersøkelsene viste at bunnområdene i Groosefjorden var tydelig påvirket av det kommunale utslippet på Groos. Bunnvannet hadde lave oksygenkonsentrasjoner og nær utslippet var bløtbunnsfaunaen dominert av arter som opptrer ved tung organisk belastning, men det var ingen større endringer i tilstanden siden forrige undersøkelse på 1980-tallet. Ved dykking ble det i tillegg registrert hydrogensulfid i sedimentene ved utslippspunktet. I overflatelaget ble det kun funnet svake effekter av utslippet. I Homborsund var det ingen større effekter av utslippet, men resultatene tyder på at området er sårbart for økning i tilførslene

Direct observation of substitutional Ga after ion implantation in Ge by means of extended x-ray absorption fine structure

We present an experimental lattice location study of Ga atoms in Ge after ion implantation at elevated temperature (250°C). Using extended x-rayabsorption fine structure (EXAFS) experiments and a dedicated sample preparation method, we have studied the lattice location of Ga atoms in Ge with a concentration ranging from 0.5 at. % down to 0.005 at. %. At Ga concentrations ≤0.05 at.%, all Ga dopants are substitutional directly after ion implantation, without the need for post-implantation thermal annealing. At higher Ga concentrations, a reduction in the EXAFS amplitude is observed, indicating that a fraction of the Ga atoms is located in a defective environment. The local strain induced by the Ga atoms in the Ge matrix is independent of the Ga concentration and extends only to the first nearest neighbor Ge shell, where a 1% contraction in bond length has been measured, in agreement with density functional theory calculations.We acknowledge the support from the Research Foundation Flanders, the epi-team from imec, the KU Leuven GOA 09/06 project, the IUAP program P6/42 and the Australian Research Council. S.C. acknowledges support from OCAS NV by an OCAS-endowed chair at Ghent University

Spatial patterns of the temporal dynamics of three gadoid species along the Norwegian Skagerrak coast

Journal home page: http://www.int-res.com/journals/meps/Time series from an extensive research survey of juveniles of cod Gadus morhua, pollack Pollachius pollachius and whiting Merlangius merlangus sampled from 1919 to 1994 at 38 stations along the Norwegian Skagerrak coast were investigated. Spatial and temporal analyses were performed to study the spatial pattern of the temporal dynamics of the 3 fish species. Spatially consistent variations were detected in abundance, year-to-year fluctuation as well as in periodicity. The spatial heterogeneity occurred at a mesoscale (differences between fjords) and at a local scale (differences between stations within a fjord) for the 3 gadoids. However, the magnitude of the spatial heterogeneity differed between species. Cod and whiting, which were more abundant in sheltered areas, showed higher spatial variability than pollack, which was more abundant in exposed locations. In this way, the spatial pattern of abundance appeared to be linked to the scale of variability of the species. All 3 species exhibit periodic fluctuations of 2 to 2.5 yr in their optimal habitats, which probably resulted from intrinsic interactions in age-structured populations, such as density-dependent competition and cannibalism. In addition, all the species exhibited long-term trends possibly due to extrinsic forces, such as environmental changes or anthropogenic influences