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This study investigates the performance of the SOPPA-based, doubles-corrected methods RPA(D) and HRPA(D) in calculating carbon-carbon spin-spin coupling constants in 39 saturated carbocycles, totaling 188 unique coupling constants. RPA(D) scales an order below SOPPA in computational complexity while HRPA(D) differs from SOPPA in the leading coefficient. These methods may therefore prove beneficial in predictions of coupling constants of large molecules. It was found that HRPA(D) significantly improves on RPA(D) for all coupling constants as well as performing similarly to SOPPA in terms of accuracy. With a roughly 50% reduction in computation time from SOPPA to HRPA(D), the latter shows great promise for the calculation of nuclear indirect carbon-carbon spin-spin coupling constants in saturated carbocycles.

In this article, the RPA(D) and HRPA(D) models for the calculation of linear response functions are presented. The performance of the new RPA(D) and HRPA(D) models is compared to the performance of the established RPA, HRPA, and SOPPA models in calculations of indirect nuclear spin–spin coupling constants using the CCSD model as a reference. The doubles correction offers a significant improvement on both the RPA and HRPA models; however, the improvement is more dramatic in the case of the RPA model. For all coupling types investigated in this study, the results obtained using the HRPA(D) model are comparable in accuracy to those given by the SOPPA model, while requiring between 30% and 90% of the calculation time needed for SOPPA. The RPA(D) model, while of slightly lower accuracy compared to the CCSD model than HRPA(D), offered calculation times of only approximately 25% of those required for SOPPA for all the investigated molecules. Fil: Schnack Petersen, Anna Kristina. Universidad de Copenhagen; Dinamarca Fil: Haase, Pi A. B.. University of Groningen; Países Bajos Fil: Faber, Rasmus. Universidad de Copenhagen; Dinamarca Fil: Provasi, Patricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Modelado e Innovación Tecnológica. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura. Instituto de Modelado e Innovación Tecnológica; Argentina Fil: Sauer, Stephan P. A.. Universidad de Copenhagen; Dinamarca

In the Fischer-Tropsch process, valuable hydrocarbons are produced using the basic starting materials hydrogen and carbon monoxide, which can be derived from alternative carbon sources such as coal, gas or biomass [1]. Although this process has been studied for almost a century, the effects of the support material on activity, selectivity and stability of the catalyst remain obscure. This study aims to gain fundamental insights into the effect of metal-support interactions in cobalt alumina based Fischer-Tropsch catalysts. To accomplish this, the effects of metal-support interactions have to be isolated from possible convoluting effects of the metal crystallite size and support porosity. This is achieved by preparing inverse-model catalysts, in which the support is deposited onto the metal, in contrast to conventional supported catalysts, in which the metal phase is deposited onto a porous support [2]. Cobalt alumina inverse-model catalysts were prepared by incipient wetness impregnation of cobalt oxide with aluminium sec-butoxide. The alumina loading was varied systematically between 0 and 2.5 wt% Al. The catalysts were characterised by X-ray diffraction (XRD), Transmission electron microscopy (TEM), H2 -chemisorption, and X-ray absorption near edge spectroscopy (XANES). The catalyst reducibility was studied by temperature programmed reduction (TPR), in situ (XRD) and in situ (XANES) experiments. The catalytic performance for the Fischer-Tropsch synthesis was studied in a slurry reactor under industrially relevant conditions. The alumina modification was found to prevent sintering and decrease the reducibility of the catalysts. With increasing alumina loading, and increasing calcination temperature, reduction peaks shifted to higher temperatures and peaks with maxima above 400 ˝C appeared in the TPR. The kinetic evaluation showed that the decreased reducibility was due to a decrease in the pre-exponential factor, which suggests that the alumina modification hindered hydrogen activation and/or nucleation of reduced cobalt phases. The activity of the catalysts for the FT reaction was found to increase with increasing alumina loading. This was likely an effect of the increase in metal dispersion upon alumina modification. Furthermore, alumina-modified catalysts had a higher C5+ and olefin selectivity, and lower methane selectivity. Pyridine-TPD experiments showed that the alumina modification introduced Lewis acid sites to the cobalt catalysts. Lewis acid sites may interact with adsorbed CO thereby weakening the C-O bond and facilitating CO dissociation. This was supported by CO-TPR experiments, which revealed that alumina-modified catalysts had an increased activity for the surface catalysed Boudouard reaction. It is concluded that the alumina modification increased the rate of CO dissociation on metallic cobalt. An increased rate of CO dissociation may lead to coverage of the metal surface with carbon thereby decreasing hydrogenation and shifting the product selectivity towards high molecular weight products. Hence, alumina may promote the selectivity of cobalt catalysts via a synergistic effect.

DLR has to submit two deliverables in work package 4. These contain experimental investigations using several measurement techniques applied at a straight turbine cascade. The measurements are divided into two parts. The first deliverable includes measurements with and without cooling. The latter contains measurements with one of the former cooling configurations and air jet vortex generators (AJVG´s), additionally. This deliverable concerns the latter one. The profile contour was designed by RRD and handed over at the beginning of the project. Besides, other partners perform numerical simulations for these flow cases. The measurements are utilized to compare them with the numerical results. The following measurement techniques are applied in this report:  Schlieren technique  Infrared thermography  Wake traverses This report is subdivided in the description of the experimental setup, the metrology and the presentation of the measurements which will be done in the chapter “Results and Discussion.”

DLR has to submit two deliverables in Workpackage 4. These contain several measurement techniques applied at a straight turbine cascade. The measurements are divided in two parts. This report includes measurements with and without cooling. The second part contains measurements with the former cooling configuration and air jet vortex generators (AJVG ́s), additionally. The second report will be delivered at the end of the project. The profile contour was designed by RRD and handed over at the beginning of the project. Besides do other partners numerical simulations for these flow cases. The following measurement techniques are applied: Schlieren technique, Infrared thermography, Hot-wire anemometry, Pressure tapping’s, Wake traverses. The hot-wire anemometry was deployed to investigate the inflow conditions. These results were already handed over to the partners, who adopt the numerical part, for their inlet boundary conditions. The measurements are utilized to compare them with the numerical results. This report is subdivided in the description of the wind tunnel system, the metrology, a subsequent chapter about uncertainties estimations and the presentation of the measurements will be done in the chapter Results and Discussion.

International audience; Air quality has become a pressing problem in Asia and specifically in China due to rapid economic development (i.e., rapidly expanding motor vehicle fleets, growing industrial and power generation activities, domestic and biomass burning). In spite of efforts to reduce chemical emissions, high levels of particle matter and ozone are observed and lead to severe health problems with a large number of premature deaths. To support efforts to reduce air pollution, the European Union is supporting the PANDA project whose objective is to use space and surface observations of chemical species as well as advanced meteorological and chemical models to analyze and predict air quality in China. The Project involves 7 European and 7 Chinese groups. The paper will describe the objectives of the project and present some first accomplishments. The project focuses on the improvement of methods for monitoring air quality from combined space and in-situ observations, the development of a comprehensive prediction system that makes use of these observations, the elaboration of indicators for air quality in support of policies, and the development of toolboxes for the dissemination of information.

This paper presents a variety of different numerical set-ups for the simulation of a straight turbine cascade ow. The DLR TRACE code was employed for the numerical investigations. Special emphasis is laid on the transition prediction applying the -Retransition model. The Re-transition model with diferent underlying turbulence models and turbulence model modifications are varied. The numerical investigations are compared to experimental data obtained at the Wind Tunnel for Straight Cascades at DLR, Göttingen. For comparison with the experimental data one exit Mach number at a low transonic region and two different incidence angles are investigated. For the measurement infrared imaging, Schlieren photography, pressure taps and hot-wire-anemometry are applied.

This thesis investigates the pragmatic competence of Danish advanced L2 learners of English. More specifically, the thesis focuses on the learners’ politeness strategies when performing the understudied speech act remindings. With the purpose to look at learners’ reminding strategies, the thesis survey was performed by means of a discourse completion task, a method which is commonly used in second language research. Aiming to find possible indications of language transfer, the learners were asked to answer to situations in L1 Danish in addition to L2 English. A group of native English speakers were moreover included in the survey, against whose answers the learners’ would be compared and contrasted. Results show that even advanced learners may have difficulties reminding in L2 English, and that they may rely on L1 pragmatic norms when communicating in a second language.

Fourier Transform Infrared (FTIR) spectrometry has been used for ground-based solar absorption, laboratory and flux measurements, to study the atmospheric composition, as well as physical and chemical processes in the atmosphere.The solar absorption FTIR measurements have been performed in Paramaribo, Suriname (5.8 N, 55.2 W) between September 2004 and November 2007 and represent the first remote sensing measurements in the inner tropics over severalyears. These measurements are of great importance for a better understanding of global climate and physical and chemical processes of the tropical atmosphere as well as for satellite validations. Vertical profiles of carbon monoxide (CO) and ethane (C2H6) and total columns of methane (CH4), hydrogen cyanide (HCN) and acetylene (C2H2) have been retrieved from the FTIR spectra. The quality of the methane retrieval was limited by the available spectroscopic data. Laboratory cell-based FTIR measurements have been performed to correct the methane spectroscopy in the infrared spectral region, which significantly improved the retrieval of methane from SCIAMACHY and FTIR spectra. The retrieval of methane profiles from near-infrared FTIR spectra by optimal estimation significantly improved the results. The FTIR observations of methane are compared with TM5 model simulations and satellite observations from SCIAMACHY, and are the first validation of the SCIAMACHY retrieval in the tropics using remote sensing techniques. The ratio CH4/CO2, which can be measured directly from SCIAMACHY and FTIR, compares very good, while the column averaged volume mixing ratio (XVMR(CH4)) of SCIAMACHY do not agree with the FTIR observations. Model assumptions areused in the SCIAMACHY retrieval to derive the XVMR(CH4) from the directly measured CH4/CO2 ratio. The worse agreement of SCIAMACHY XVMR(CH4) with FTIR compared to the SCIAMACHY CH4/CO2 ratio with FTIR could be attributed to unrealistic model assumptions used in the SCIAMACHY retrieval that led to wrong time series of the column averaged CH4 VMR. There is a good agreement of the FTIR XVMR(CH4) with the TM5 model. FTIR observations of carbon monoxide agree well with satellite data from the MOPITT instrument for all of the measurement campaigns. Simulations of CO and C2H6 from the MATCH-MPIC model reproduce the mean vertical structure of the FTIR observations. The model is generally not able to reproduce the extreme enhancements seen during the specific biomass burning events by both observation instruments. Nevertheless, the model indicates that beyond the backgroundsource of CO from methane oxidation, the main contributions to the CO mixing ratios are the episodic convective injection of NMHCs and CO from South American biomass burning into the upper troposphere, along with long range transport of African biomass burning CO, particularly during spring. Revised simulation of the MATCH-MPIC model with improved biomass burning emissions still fails toreproduce most of the individual observed pollution events. It generally underestimates the observed concentrations of carbon monoxide and ethane. The revised model is in better agreement with the observations in the upper troposphere, while in the boundary layer and lower troposphere the revised model underestimates the FTIR measurements and results in underestimated total columns. Current generationatmospheric chemistry models underestimate OH is the tropical region and compensate for this part by too low isoprene emissions. It is speculated that, if a mechanism like e.g. isoprene recycling and realistic isoprene emissions would be included in current models, it would result in a powerful CO source in the boundary layer over Suriname from the isoprene oxidation. The CO oxidationrate would also increase due to higher OH concentrations. Because of the complex chemistry and transport processes, it is difficult to predict the exact changes without having done the simulations. The last part of this work presents the development of an advanced flux measurement technique, consisting of a cell-based FTIR analyser and a Relaxed Eddy Accumulation (REA) system, to enable automated and continuous flux measurements of atmospheric trace gases. The combination of the REA technique with the FTIR analyzer was tested successfully in the lab and during a three weeks field campaign. The FTIR-REA technique offers the capacity to measure a range of gases simultaneously under field conditions and enables long-term measurements and monitoring of atmospheric greenhouse gas fluxes.

Huvudsyftet med vår uppsats var att i första hand undersöka vilka intentioner som låg bakom idén att införa en obligatorisk historiekanon i den danska grundskolan, men även se hur Svend Sødring Jensens tre historieundervisningsteorier kan tillämpas i den danska kanonrapporten.Resultatet visade att kanonrapporten först och främst kritiserade de danska elevernas kunskaper i historia och kronologi samt lärarnas bristfälliga kunskaper i ämnet. Detta var också de huvudargument som försvare och förespråkare för en obligatorisk historiekanon manade fram i den aktuella debatten kring ämnet. Resultatet av vår studie kring kanon-rapporten kunde vi även härleda till två av Sødring Jensens tre undervisningsteorier, det vill säga den objektivistiska och klassiska teorin. Vi hade även som syfte att undersöka hur de danska lärarna såg på förslaget med en obligatorisk kanon. Det vi kom fram till var att lärarna var tillfredsställda med de mål som läroplanen för historia från år 2004 behandlar, och att en obligatorisk kanon inte skulle förändra elevernas syn eller kunskap när det gäller historieämnet. Lärarna uppfattade även införandet av en nationell kanon som något konservativt och nationalistiskt. Pedagogerna ansåg även att historiemedvetenheten skulle ligga i fokus och inte de kronologiska kunskaperna något man kan återföra till Sødring Jensens tredje teori, det vill säga den formala undervisningsteorin. Emellertid ansåg lärarna att ett examensprov i historia förmodligen skulle stärka ämnets status bland både elever och lärare. Vi hade även som avsikt att göra en undersökning kring elevers syn på historieämnet samt deras kunskapsnivå i historia. För att sedan själva tolka huruvida en styrd kanon behövs eller ej. Resultatet av denna undersökning visade att det fanns ett intresse för historieämnet, men att de kronologiska kunskaperna var bristfälliga. Dock visade eleverna prov på historiska faktakunskaper och en personlig historiemedvetenhet. Med utgångsläge av denna under-sökning menar vi, att den kanonrapport och de argument som urvalsgruppen presenterar inte kommer till att gynna elevernas historieutveckling.

Background: Febrile seizures are common in childhood. When a child is stricken with febrile seizures it is not only the child that is suffering, in fact the whole family is affected. There are different ways to prevent recurrence of febrile seizures, such as use of different drugs. The parents also need information about febrile seizures and support from the nurse. Aim: The aim of this literature study was to illuminate the nurse’s preventive work for children who have been stricken with febrile seizures. Method: A literature search was conducted in different databases. A qualitative content analysis of 10 scientific articles was performed. Result: The result was presented in three main categories. The first main category was the parents’ role; such as fear, lack of knowledge and concerns about the feature. The second main category was preventive caring, such as sponging, and the third one was the use of preventive drugs such as diazepam and antipyretics. Conclusion: The authors conclude that there is a large need of modern research in the aim of nursing of children with febrile seizures.

60 pp. (1978).

94 pp. (1974).