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At the district heating plant of Kalmar, Sweden an on-line unit for production of granulated wood ash for nutrient recycling on forest soils is being applied. Currently, the granules are dried by hot air from an oil-fired burner. The objective of this work was to investigate how drying by flue gas affects the hardening of granules, or impacts their chemical composition and properties. Ninety-six granule samples were treated by flue gas from natural gas combustion in a laboratory pilot scale flue gas generator. CO 2 , CO, O 2 , C 3 H 8 and NO concentrations were varied during the experiment. Additionally, some samples were treated by flue gas from combustion of sawdust at the heating plant in Kalmar. Drying by flue gases did not affect the chemical composition of granules, but minor effects were seen in their mineralogy. The carbonate content was slightly higher in granules treated with flue gas from natural gas combustion compared to the granules dried by hot air only, when measured by wet chemical methods. Results from XRD analysis imply that the calcite content is higher and the portlandite and arcanite content slightly less in granules treated with flue gas from sawdust combustion compared to the granules dried by hot air only. The results from this investigation showed no negative effects on ash granule composition or physical structure by the use of a flue as a drying medium.

The first evidence for excited states in Ag-95 is presented. Ag-95 is the heaviest T-z = 1/2 nucleus for which gamma-rays have been identified. The reaction Ca-40(Ni-58, 1p2n)Ag-95 was used in the ...

A demonstrator of Computed Tomography (CT) has been designed and built for educational purposes. The system is based on a solid-state CdZnTe detector and a standard PC. The mechanics of the system is controlled and data is acquired by programs written in LabVIEW. CT images are reconstructed using MATLAB programs.

Chemical composition and leaching characteristics of granules made of wood ash and dolomite

High-temperature superconductivity emerges from an un-conventional metallic state. This has stimulated strong efforts to understand exactly how Fermi liquids breakdown and evolve into an un-conventional metal. A fundamental question is how Fermi liquid quasiparticle excitations break down in momentum space. Here we show, using angle-resolved photoemission spectroscopy, that the Fermi liquid quasiparticle excitations of the overdoped superconducting cuprate La1.77Sr0.23CuO4 is highly anisotropic in momentum space. The quasiparticle scattering and residue behave differently along the Fermi surface and hence the Kadowaki-Wood's relation is not obeyed. This kind of Fermi liquid breakdown may apply to a wide range of strongly correlated metal systems where spin fluctuations are present.

We present angle-resolved photoemission spectroscopy data on moderately underdoped La1.855Sr0.145CuO4 at temperatures below and above the superconducting transition temperature. Unlike previous studies of this material, we observe sharp spectral peaks along the entire underlying Fermi surface in the superconducting state. These peaks trace out an energy gap that follows a simple d-wave form, with a maximum superconducting gap of 14 meV. Our results are consistent with a single gap picture for the cuprates. Furthermore our data on the even more underdoped sample La1.895Sr0.105CuO4 also show sharp spectral peaks, even at the antinode, with a maximum superconducting gap of 26 meV.

A demonstrator of computed tomography (CT) has been designed and built for educational purposes. The system is based on a solid state CdZnTe detector and a standard PC. The mechanics of the system is controlled and data is acquired by programs written in LabVIEW. Computed tomography images are reconstructed using MATLAB programs.

We have performed an angle resolved photoemission study on a single crystal of the optimally electron doped (n-type) cuprate superconductor Nd2-xCexCuO4 (x=0.15) at a photon energy of 400 eV. The Fermi surface is mapped out and is, in agreement with earlier measurements, of hole-type with the expected Luttinger volume. However, comparing with previous low energy measurements, we observe a different Fermi surface shape and a different distribution of spectral intensity around the Fermi surface contour. The observed Fermi surface shape indicates a stronger electron correlation in the bulk as compared to the surface.

The glacial moraine along the Baltic Sea of the south-eastern coast of Sweden is composed mainly of porous and soft Lower Cambrian sandstone and hard granite together with small amounts of alkaline amphibolite and diabase. Our objective was to determine whether the chemical and structural properties of these bedrock types, in combination with wave exposure, affect germling survival and adult plant density of Fucus vesiculosus L. commonly found growing on stones and boulders in the area. The number of surviving F. vesiculosus germlings was found to be similar on the alkaline amphibolite and diabase (1.0×10 4 ′0.8×10 3 ind. m - 2 ). It was significantly higher than on the acidic porphyry, sandstone, granite, and gneiss (0.6×10 4 ′0.5×10 3 ind. m - 2 ) after two months of growth. These results indicate that small-scale differences in surface structures such as porosity, holes and fissures may affect the survival of early stages of F. vesiculosus germlings in the Baltic Sea. Also the natural density of F. vesiculosus individuals at the wave-exposed site was shown to differ depending on bedrock type, with the highest number of plants on sandstone (1893′125 ind. m - 2 ) followed by granite (405′28 ind.m - 2 ) and amphibolite (374′33 ind. m - 2 ). Contrary to the wave-exposed site, the density of plants was similar on all three types at the sheltered site. Further, the attachment strength of adult F. vesiculosus specimens was similar, i.e. 57.6′4.1 N and 61.8′6.8 N on granite and sandstone, respectively, and significantly higher than on amphibolite (36.3′4.2 N). Thus we suggest that the distribution and proportion of different bedrock types on a moraine coast may affect both the survival of Fucus germlings on a very small scale and may affect the density of plants due to differences in attachment strength and impact of waves.

The following transferred research effort referred to is a 10-year cooperative agreement between the Swedish Defence Research Establishment (FOA) and the civilian co-partner, the National Board of Technical Development (STU). The latter is the largest funding organization in Sweden for the support of technical R&D.

This paper describes the design, calibration and performance of a Cpl coherent laser radar testbed. For calibration purposes, a very precise movable target, resembling the travelling Michelson interferometer commonly adopted in laser wavelength measuring apparatus, has been designed. Different types of targets, e.g. mirrors and diffuse targets have been used to characterize the optical efficiency of the laser radar and the signal fluctuations induced by target surface or turbulence. A number of laser radar images are presented and the target detection problem is discussed in conjunction with these images. By an example using measured atmospheric attenuation statistics, we conclude that a CO2 laser radar can obtain acceptable performance out to 5 - 6 km range during moderate turbulence conditions.

A pulsed CO2 lidar was used to measure atmospheric extinction and backscattering at 10 μm during different types of weather. Comparison was made between extinction evaluated from the atmospheric echo and from measurements against calibrated plates. Vertical soundings showed that the backscatter could drop a factor of 10 during the first kilometer. The implications of extinction and backscatter to the performance of single-ended CO2 lidars for atmospheric sensing are discussed.