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Hydrogenolysis of ethane on silica-supported cobalt catalysts

The kinetics of ethane hydrogenolysis over cobalt catalysts supported on silica has been investigated. The results compare well with previous data from Sinfelt et al., Haddad and Goodwin, and Babernics et al. The data were found to be characterized by an isokinetic temperature, T-iso = 490+/-40 K and it was therefore possible to apply the model of selective energy transfer (SET). This approach ind

Luminescence from inter-chain aggregates in polythiophene films

We report time-resolved photoluminescence of two polythiophene derivatives with different chain packing. Emission of inter-chain aggregates is distinguished from that of intra-chain singlet excitons. The aggregate luminescence is shifted towards lower energies relative to that of intra-chain exciton by 0.17 eV, and the Huang-Rhys factor of the coupling to the intra-chain C double bondC vibration i

Cumulative revision rate with the Scan Hip Classic I total hip prosthesis. 1,660 cases followed for 2-12 years

We analyzed the cumulative revision rate in 1,474 patients (1,660 hips) operated on with a cemented Scan Hip Classic I prosthesis from November 1983 to January 1994 at Lund University Hospital. The revision rate was analyzed for 3 diagnoses--arthrosis, rheumatoid arthritis and complication after a hip fracture--and for 2 head diameters--22 and 32 mm. Until January 1996, 36 hips were revised: 31 be

Expression of human all-trans-retinoic acid receptor beta and its ligand-binding domain in Escherichia coli

all-trans-Retinoic acid, one of the hormonally active derivatives of vitamin A, occurs physiologically in plasma at a concentration below 10 nmol/l. The methods currently used for its quantification are based on HPLC, need about 1 ml of serum, are relatively laborious and thus not well suited for mass analysis. The affinity and specificity of retinoic acid receptors for all-trans-retinoic acid enc

The FERRUM project: improved experimental oscillator strengths in CrII

We report absolute oscillator strengths for 119 Cr II transitions in the wavelength region 2050-4850 angstrom. The transition probabilities have been derived by combining radiative lifetimes, measured with time- resolved laser induced fluorescence, and branching fractions from intensity calibrated Fouirer transform spectrometer data. New radiative lifetimes for the 3d(4)(D-5)4p F-4, D-4 and P-6 te

The Recontextualisation of Social Pedagogy. A study of three curricula in the Netherlands, Norway and Ireland.

Popular Abstract in Swedish Avhandlingens syfte är att beskriva, analysera och jämföra rekontextualiseringen av socialpedagogik i tre olika curriculum; I Nijmegen (Nederländerna), Lillehammer (Norge) och Sligo (Irland). Rekontextualisering, ett begrepp hämtat från Basil Bernstein, syftar på den transformation som sker när socialpedagogik flyttas in i ett undervisningssammanhang. Materialet bestårThe purpose of this thesis is to describe, analyse, and compare the recontextualisation of social pedagogy in three different curricula; in Nijmegen (NL), Lillehammer (N), and Sligo (IRL). The curricula represent different academic orientations and are located in different social-political contexts. The recontextualisation of social pedagogy, the concept derived from the works of Basil Bernstein,

Bootstrap control

In this paper, we present a new way to control linear stochastic systems. The method is based on statistical bootstrap techniques. The optimal future control signal is derived in such a way that unknown noise distribution and uncertainties in parameter estimates are taken into account. This is achieved by resampling from existing data when calculating statistical distributions of future process va

Disruption of the microbial food web and inhibition of metazooplankton development in the presence of iron- and DOM-stimulated Baltic Sea cyanobacteria

Summer N-2-fixing cyanobacterial blooms are a common feature in the Baltic Sea, and the occurrence of Nodularia spumigena toxic blooms is of particular concern. Cyanobacterial blooms can be favoured by certain conditions including high concentrations of dissolved organic matter, which may increase the availability of iron critical for N-2 fixation. Cyanobacteria may negatively affect grazers becau

Particle number projection in the macroscopic-microscopic approach

We perform nuclear ground-state pairing calculations with the monopole pairing interaction. The particle number fluctuations are taken into account by the particle number projection method, with variation after projection. The pairing-correction energies obtained in this approach are compared to the BCS-model results. We discuss extensively how to properly incorporate different pairing models in g

Spectroscopic techniques for photodynamic therapy dosimetry

Popular Abstract in Swedish Denna avhandling handlar till stora delar om fotodynamisk tumörterapi (PDT). PDT har sedan början av förra århundradet undersökts som ett tänkbart alternativ till strålningsbehandling, kirurgi och kemoterapi för behandling av cancertumörer i kroppen. Precis som namnet antyder involverar metoden en fotodynamisk reaktion. För att denna reaktion skall ske behövs tre kompoPhotodynamic therapy (PDT) as a cancer treatment modality relies on the simultaneous presence of three components; light, photosensitiser and oxygen. Once excited by the light, the photosensitiser can interact with oxygen, leading to the formation of toxic oxygen species. These reactive substances induce cellular damage within the irradiated tissue volume. PDT has been investigated for treating ma