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This publication outlines some of the most important trends and reforms that have taken place within the Swedish vocational education and training (VET) system during the 1990s. It discusses how educational policy makers in Sweden are trying to find new combinations of the traditional apprenticeship model and the dual system on the one hand, and the use of a more integrated system on the other. It suggests that lifelong learning has to be analysed in a more specific context with respect to closing specific skill shortages and implementing social, economic and institutional measures to enhance skill upgrading, on-the-job training and lifelong learning for various groups.
N/A / Link / Lindell , Mats / 2002

Luleå tekniska universitet Övrigt
N/A / Link / Olsson , Marita / 2002

Luleå tekniska universitet Övrigt
It has been suggested in the literature that the Kelvin-Helmholtz instability can be responsible for significant ion loss at Mars through the detachment of ionospheric plasma clouds. Clouds of detached ionospheric plasma were observed at Venus by the Pioneer Venus orbiter. The conditions at Mars differ somewhat from those at Venus. The ratio between the ion gyro radius and the radius of the planet is larger at Mars than at Venus, since Mars is a smaller planet and the solar wind magnetic field is weaker at Mars than at Venus. It is therefore interesting to study instabilities at Mars and to compare the results from Mars with those from Venus. We search the ASPERA-3 data for signatures of instabilities at Mars, in particular looking at the magnetosheath and the induced magnetosphere boundary.
N/A / Link / Gunell , H. / 2006

An LCAO scheme taking into account 10 atomic orbitals (s-, p-, and d-type) applied to a supercell containing 256 atoms is used to calculate the bound states of the reconstructed 90° partial dislocation in Si. The results differ significantly from our earlier calculations on the unreconstructed 90° partial using the same method. We find two bands separate from each other in the entire Brillouin zone and the upper band penetrates deep into the indirect band gap which is in contradiction with the general opinion that core reconstruction clears the band gap of dislocation states.
N/A / Link / Marklund , Sune / 1992

Luleå tekniska universitet Övrigt
Hydrocracking of methyldecalin over Pd/REX has been studied with surface sensitive techniques in the critical temperature range 325-350°C. Results from in situ characterization of adsorbed species, and post-reaction analysis of the catalyst surface by infrared and photoemission spectroscopies, were related to product distributions. The results are discussed in light of quantum chemical calculations of free and catalyst bound intermediates, following ring-opening reactions. Liquid and gaseous products were detected by infrared and UV/Vis spectroscopies. Apparent activation energies of product formation hydrogen consumption, over a broader temperature range, were derived from previous autoclave experiments. An increase in temperature, 325-350°C, results in a shift from preferred cracking products to aromatics, an enhanced level of light hydrocarbon off-gases, and a higher coverage of carbonaceous residues. The increased level of carbonaceous residues is accompanied by a lowered coverage of the reactant, at the surface. The altered product distribution can be characterized by apparent single activation energies, valid from 300 to 450°C. Methane and aromatics show a similar rapid increase with temperature, hydrogen consumption a more timid increase, indicating a reaction limited by diffusion, and cycloalkane production a modest inverse temperature dependence. Fully hydrogenated ring-opening products represent valuable fuel components, but hydrogen deficiency can instead lead to chemisorbed precursors to coke. Our calculations show that cyclohexane, 1,2-diethyl, 3-methyl has a lower heat of formation than the corresponding surface intermediates, but a small enthalpy advantage can easily be countered by entropy effects at higher temperatures. This balance is critical to the formation of preferred products, instead of catalyst deactivation and aromatics. The theoretical results further show that surface intermediates, where the terminating hydrogen is replaced by a C-O bond, have distinct vibrations around 1150 cm-1.
N/A / Link / Sayan , S. / 2000

N/A / Link / Kaplan , Alexander / 2006

Luleå tekniska universitet Övrigt
978-91-44-04136-0 / Link / Björkman , Torsten / 2002

90-5201-998-3 / Link / Frick , Kaj / 2002

Luleå tekniska universitet Övrigt
N/A / Link / Gunnarsson , Ewa / 2002

91-7373-444-6 / Link / Laitila , Lars / 2002

Luleå tekniska universitet Övrigt
N/A / Link / Öhlander , Björn / 1983

N/A / Link / Ingri , Johan / 1985

0-8194-3847-2 / Link / Resch , M. / 2001

1424409306 / Link / Bergström , David / 2007

Luleå tekniska universitet Övrigt
N/A / Link / Roininen , Sari / 2005

Luleå tekniska universitet Övrigt
Aerobically digested sludge from a small wastewater treatment plant was dewatered on five sand drying pilot beds and four small drainage beds. The experiment was conducted in a controlled environment with constant air humidity and temperature. A total of between 147 and 263 kg of a combined biological-chemical sludge was used on each of the sand drying beds. Initial bed total solids (TS) content was 4. 6-5.5 %. Sludge drainage was completed within 28 days, and the thinner sludge layers were drained within 16 days. The sludge evaporation phase, prior to equilibrium with air moisture, lasted a maximum of 84 days and resulted in a final TS content of 88-92 %. The drying time to achieve 30% TS was 35-40 days, depending on initial sludge thickness. Sludge cracking behaviour or rate did not control the drying time at less than 30% TS.
N/A / Link / Marklund , Stefan / 1993

An LCAO-scheme taking into account 10 atomic orbitals (s-, p-, and d-type) is used to calculate the electronic structure of the reconstructed 90° partial dislocation in Si. Two different valence force fields producing deviating results are used for modelling the core structure. Geometrical data published by another group is also used. The aim is to explore the influence of geometry on energy levels. We find that the band structure depends sensitively on bond angles. Using data determined by the Tersoff potential we obtain two bands of which the upper one penetrates deeply into the indirect band gap while the geometry minimizing the simple Keating potential leaves the gap completely clear of dislocation states. Thus, from a theoretical point of view, the chief difficulty in calculating the electronic structure of the reconstructed 90° partial is the lack of accurate structural information.
N/A / Link / Marklund , Sune / 1994

Luleå tekniska universitet Övrigt
This paper is concerned with exploring the changing character of work in higher education in Sweden and England. A study of this kind is timely not least because both countries have been subjected to a series of changes in recent years in their respective public sectors (Berg 2000; Clarke and Newman 1997) - with universities, according to some sources, significantly affected (Barry, Chandler and Clark 2001; Askling 1999; Fogelberg et al 1999; Prichard and Willmott 1997; Parker and Jary 1995). Yet the implications for female academics is only belatedly being recognised (Goode and Bgilhole 1998; Morley 1999; Edgren 1999; Clark, Chandler and Barry 1999; Berg 2001). The paper accordingly extends existing research by conceptualising areas of academic responsibility along the following dimensions: dog work, tough work, care work, real work and nice work respectively, in order to explore the changing character of intellectual labour and the gendered implications. Undervalued in relation to other areas of intellectual labour administrative or dog work has always been the province of academics, especially during their early years in the job when they take their turn as others before them. Recent years have seen a growth in routinised tasks with increasing bureaucratisation and seemingly endless paper trails attending peer review of quality audits as trust in professional discretion recedes (Power 1997). Increasingly administration is delegated to junior colleagues and administrators (or student support managers), often women. Organising the work of professional colleagues has likewise traditionally been the province of academics. Arranging timetables and 'persuading' colleagues to undertake heavy teaching loads and committee work has always been difficult and burdensome for those responsible. This tough work has recently been on the increase as Heads of Department, now seen as middle managers, are exhorted to manage the work of their junior colleagues, delegating academic leadership as necessary (Jarrett 1985).Where enacted in hard or brutal ways the gendered element of tough work becomes clear (Gilligan 1982; Rosener 1990; White 1995). Care work has been thought traditionally to be a significant factor in supporting students at university and reducing the wastage rates associated with systems of mass higher education (Halsey 1995). The pressures to massify into a New Higher Education system (Parker and Jary 1995) appear to have had a deleterious effect with those most affected being women, both as tutors and students (Cotterill and Waterhouse 1998). These are the staff forced to deal with the harder realities of daily life on campus for the newly (dis)possessed student 'customers'. Real work has historically characterised the role of academic labour, as lecturers seek to develop the spirit of intellectual enquiry and joy of learning in their students. In the face of attempts to speed up academic production, and make the job harder (Morley 1999:166), intellectual workers resist through trade union action, collegial support for one another and control of working patterns, taking work home where they can at least manage their time to some degree, and maintaining responsibility for content of lectures, seminars and tutorials as numbers grow. Here the greatest number of hours are invariably worked by the most junior lecturing staff who are women. Nice work on the other hand has offered sanctuary, an escape route to the pleasures of reflection where independence remains intact. And it is here too that men outnumber women in senior research positions. Whilst there may exist illusion in the dream of independence, as pressure for published output and income generation through research grants grows and makes the work much harder than it was before, it remains nice work if you can get it, perhaps the final refuge of beleaguered, predominantly male, academics keen to maintain professional autonomy. And it here that women are excluded - not just in Sweden and England but in many other countries around the world (Clark,Barry and Chandler 1998:209). The data for the paper derives from a series of in-depth interviews with female and male academics in middle management positions in Sweden and England in order to give voice to their experience of these recent changes.
91-7045-640-2 / Link / Berg , Elisabeth / 2002

Luleå tekniska universitet Övrigt
Drying from a free water surface and from a waste activated sludge was studied in three separate experimental arrangements. Evaporation in a closed chamber with a surface area of 1.0 m2 was studied with temperatures between 20 and 60°C and air flows between 75 and 300 m3/hour. The rate of evaporation varied between 351 and 746 gram/m2 hour. The efficiency varied between 11 and 20%. To increase the efficiency the air-liquid area has to be enlarged. Evaporation from two pilot sludge drying beds was studied in an open air test lasting four months. One similar bed was tested in a controlled environment. The results showed that above a critical moisture content between 600 and 1100% evaporation from sludge equals the rate of evaporation from a free water surface. Below the critical moisture level the rate decreases rapidly.
N/A / Link / Marklund , Stefan / 1990

Luleå tekniska universitet Övrigt
91-7045-640-2 / Link / Berg , Elisabeth / 2002

Luleå tekniska universitet Övrigt
Zeolite ZSM-5 (SiO2/Al2O3 ratio 53:1) ion exchanged with Cu2+ to 0%, 74% and 160% was characterized by X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Infrared (IR) spectroscopy, Electron spectroscopy for chemical analysis (ESCA) and ammonia desorption. A more limited set of data was obtained for Cu-ZSM-5-33, ion exchanged with 0%, 104% and 210% Cu2+ ions. All catalysts lose water below 100°C. More strongly bound water, approximately two molecules per Cu2+ ion, emerge at a higher temperature. This corresponds either to an incomplete hydration shell for zeolite-bound Cu2+ ions or to the decomposition of Cu(OH)2 and simultaneous reactive adsorption of copper ions on the inner surface of the zeolite. The process occurs in the same temperature range, 150-350°C, where XRD reveals rearrangements in the H-form of the catalyst. Reactions between the exchangeable cations and the zeolite appear critical for lattice changes and possibly the formation and dispersion of catalytically active centers at these temperatures. Dehydroxylation and water desorption are observed between 350°C and 450°C for H-ZSM-5. This temperature range overlaps with the light-off temperature for direct NO decomposition over Cu-ZSM-5. This coincidence can be rationalized in terms of two effects of enhanced ionic mobility and dynamics of the zeolitic framework. ESCA shows that partial reduction, cupric to cuprous, occurs as a result of annealing in the same temperature range. It has been suggested that NO-derived surface intermediates act as site blockers for the direct decomposition below the light-off temperature until destabilized by lattice movements. The lower stability and thus higher mobility of low SiO2/Al2O3 ratio ZSM-5 zeolites would then rationalize an advantage of these materials as supports in catalysts for direct NO decomposition.
N/A / Link / Ganemi , B. / 2000

N/A / Link / Gedda , Hans / 2003

Luleå tekniska universitet Övrigt
978-952-214412-6 / Link / Kaplan , Alexander / 2007

Luleå tekniska universitet Övrigt
978-952-214412-6 / Link / Engström , Hans / 2007

Luleå tekniska universitet Övrigt
91-972568-8-9 / Link / Trojer , Lena / 1999

N/A / Link / Grevholm , Barbro / 2004

The activation of CO2 in thin potassium layers adsorbed on Cu(1 1 1) has been studied with time-evolved Fourier transform-infrared reflection absorption spectroscopy. The growth of thin layers by reactive evaporation of potassium in a CO2 atmosphere permits control of the K:CO2 stoichiometry, which strongly affects the selectivity in the formation of intermediates and the decomposition pathways of the layer. Layers grown in a CO2 rich atmosphere exhibit the preferential growth of stoichiometric potassium oxalate K2C2O4 (D2h). The molecular identity of oxalate with D2h symmetry is confirmed by vibrational spectra utilizing isotopic substitution methods (13CO2 and C18O2) and by the use of isotopic mixtures of CO2/C18O2 and CO2/13CO2. A comparison of the isotope data with theoretical calculations gives an estimated OCO bond angle in oxalate of 132°. Far-IR spectra obtained with synchrotron radiation indicate the equivalent interaction of all oxygen atoms with the potassium. A comparison of the vibrational data with theoretical ab initio calculations confirms the structural model of an oxalate species that is bulk coordinated with no strong directional bonding and all oxygen atoms equally interacting with potassium. At medium and low CO2:K ratios, very complex vibrational spectra are observed, indicating the formation of an oxalate surface species with C2v symmetry in addition to D2h- oxalate, CO2- and CO22- species.
N/A / Link / Paul , Jan / 2003

N/A / Link / Svoboda , Ales / 1998

Luleå tekniska universitet Övrigt
N/A / Link / Kaplan , Alexander / 2005