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Abstract in Undetermined Debattinlägg om akademisk frihet inom ramen för serie med gästkrönikörer.

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High-resolution transmission electron microscopy characterization of molybdenum oxide catalyst precursors is carried out for a better understanding of the mechanisms leading to the active catalytic material. The precipitated material consists of both large-unit cell crystals and randomly orientated clusters on a 3-5 nm scale. The crystalline clusters are embedded in non-crystalline material, preve

In this thesis we investigate the applicability of wavelets to simulate the time behavior of elastic multibody systems (MBS) with contact constraints. For this end, a wavelet element method (WEM) was implemented, exploiting the special structure of the coupled ODE/PDE equations that govern elastic MBS. Special care has to be taken to adapt the method to the particular geometry of the elastic bodi

The main purpose of this study is to develop a SPME calibration method suitable for use in evaluation of concentrations of hydrophobic substances in environmental samples. The analyte used in the experiments was alpha-pinene, a hydrophobic organic compound commonly found in wood, and therefore found in wood storage facilities, wood processing industries and wood based biofilters. The SPME fibres w

Consider a spatial multibody system with rigid and elastic bodies. The bodies are linked by rigid interconnections (e.g. revolute joints) causing constraints, as well as by flexible interconnections (e.g. springs) causing applied forces. Small motions of the system with respect to a given nominal configuration can be described by linearized dynamic equations and kinematic constraint equations. We

We present in this work in vitro measurements of the force ejecting DNA from two distinct bacteriophages (T5 and lambda using the osmotic-suppression technique. Our data are analyzed by revisiting the current theories of DNA packaging in spherical capsids. In particular we show that a simplified analytical model based on bending considerations only is able to account quantitatively for the experim

Silver recovery from photographic fixing solutions is investigated by applying solvent extraction techniques. Amines were shown to be the most promising extractants and quaternary ammonium chlorides selected for further studies because of high distribution coefficients and low pH-sensitivity. The distribution coefficient for silver from a 0.5 M ammonium thiosulphate solution increases from 2.3 to

We propose a new third-order multidimensional upwind algorithm for the solution of the flow equations on tetrahedral cells unstructured grids. This algorithm has a compact stencil (cell-based computations) and uses a finite element idea when computing the residual over the cell to achieve its third-order (spatial) accuracy. The construction of the new scheme is presented. The asymptotic accuracy f

OBJECTIVE: The study was designed to investigate the prevalence of celiac disease (CD) among 2.5-year-old children in a Swedish urban population with a high incidence of CD.MATERIAL AND METHODS: Six hundred ninety apparently healthy children, born in the 12-month period of July 1992 through June 1993, were screened for immunoglobulin A (IgA) antigliadin antibodies and IgA antiendomysium antibodies

We have written a Fortran program BCVEGPY, which is an event generator for the hadronic production of the B-c meson through the dominant hard subprocess gg --> B-c(B-c(*)) + b + c. To achieve a compact program, we have written the amplitude of the subprocess with the particle helicity technique and made it as symmetric as possible, by decomposing the gluon self couplings and then applying the symm

Particle separation is one of the fundamental processes in wastewater treatment and a good understanding of the basic separation mechanisms ? sedimentation, flotation and filtration ? is critical in the design of wastewater treatment systems. Upgrading of treatment plants for enhanced primary treatment and effluent polishing are current examples of applications where effective, high-rate separatio

We present new measurements of radiative lifetimes for six energy levelsof singly ionized uranium, U II, using laser-induced fluorescencetechnique. One of the levels,5f³6d7p⁶M_13/2 at 26191 cm^-1,decays by a transition at 3859.6 Å. This line has recently beenobserved in the spectrum of the metal-poor star CS1082-001, the firstdetection of uranium outside t

Hydrolysis of the straw material Paja Brava, a sturdy grass characteristic for the high plains of Bolivia, was studied in order to find suitable conditions for hydrolysis of the hemicellulose and cellulose parts. Dried Paja Brava material was pre-steamed, impregnated with dilute sulfuric acid (0.5% or 1.0% by wt), and subsequently hydrolyzed in a reactor at temperatures between 170 and 230 degrees

Swedish legislation and international norms emphasize society's obligation to ensure general accessibility. The possibility of independent outdoor mobility, transportation, and travel are as important for individuals with reduced functional capacity as for other members of society, but today their mobility is limited. The aim of this article is to outline a novel field for research collaboration b