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The purpose of this paper is to discuss the requirements and challenges of pyrolysis oil's transportation in Finland. Pyrolysis oil is a new type of renewable liquid fuel that can be utilised in applications such as heat and electricity production. It has never been transported on a large scale in Finland. Possible options are transport by road, rail and waterway. The most significant requirements in its transportation are created by acidity and high density of pyrolysis oil, which impose requirements for the materials and transport equipment. The study described here shows that constant domestic transportation of pyrolysis oil is most reasonably operated with tank trucks. Rail-based transport may have potential for domestic fixed routes, and transport by water could be utilised in exporting. All transportation methods have limitations and advantages relative to each other. Ultimately, the production site and end-user's locations will determine the most suitable transport method. 相似文献
64.
Decanter centrifuges are used widely in the chemical and process industries for dewatering and classification of solid-liquid suspensions. The most important applications of this class of centrifuges are found in wastewater sludge treatment and in pigment production. The objective of this study was to investigate the operation of a pilot scale decanter centrifuge in a challenging dewatering application. Dewatering tests were performed using fine-particle slurries consisting of water and various concentrations of kaolin. In addition to the solid concentration of the feed, the feed rate of the suspension and the differential speed between the bowl and the conveyer screw were also chosen as variables. The experimental conditions were selected according to a factorial test design and the responses monitored included the production capacity (productivity) of the decanter, the solid contents of the cake and the centrate, as well as the time that was required for the stabilization of the test unit. The results obtained clearly showed that the studied variables have a significant influence on the performance of the dewatering process. The variables were also able to explain the dewatering results at a high level of statistical significance. The repeatability of the experiments was, in most cases, good: On average, the relative standard deviations for the productivity and the solid contents of the cake were 6.0% and 0.5%. It was also apparent that random variations in the feed conditions may have a remarkable and long-lasting impact on the operation of the centrifuge. 相似文献
65.
Antti Ojala Andreas Petersen Andreas Fuchs Robert Lovrincic Carl Pölking Jens Trollmann Jaehyung Hwang Christian Lennartz Helmut Reichelt Hans Wolfgang Höffken Annemarie Pucci Peter Erk Thomas Kirchartz Frank Würthner 《Advanced functional materials》2012,22(1):86-96
In this study the charge dissociation at the donor/acceptor heterointerface of thermally evaporated planar heterojunction merocyanine/C60 organic solar cells is investigated. Deposition of the donor material on a heated substrate as well as post‐annealing of the complete devices at temperatures above the glass transition temperature of the donor material results in a twofold increase of the fill factor. An analytical model employing an electric‐field‐dependent exciton dissociation mechanism reveals that geminate recombination is limiting the performance of as‐deposited cells. Fourier‐transform infrared ellipsometry shows that, at temperatures above the glass transition temperature of the donor material, the orientation of the dye molecules in the donor films undergoes changes upon annealing. Based on this finding, the influence of the dye molecules’ orientations on the charge‐transfer state energies is calculated by quantum mechanical/molecular mechanics methods. The results of these detailed studies provide new insight into the exciton dissociation process in organic photovoltaic devices, and thus valuable guidelines for designing new donor materials. 相似文献
66.
Strohmeier Dagmar; K?rn? Antti; Salmivalli Christina 《Canadian Metallurgical Quarterly》2011,47(1):248
This study (a) compared native Finns and immigrant children with respect to different forms of peer victimization and (b) tested whether intrapersonal (e.g., depression) and interpersonal (e.g., peer rejection) risk factors help to explain the association between immigrant status and peer victimization. The sample was drawn from the first phase of a large intervention evaluation project, KiVa, in Finland, composed of 4,957 native Finns (51% girls), 146 first-generation immigrants (48% girls), and 310 second-generation immigrants (53% girls) 9 to 12 years of age. The concurrent data included self- and peer reports collected via Internet-based questionnaires. Compared with native youth, first- and second-generation immigrants were more often targets of both peer- and self-reported victimization. Both immigrant groups experienced higher levels of physical, racist, and sexual victimization than natives. Furthermore, second-generation immigrants reported higher levels of property damage, threats, and cybervictimization than native Finns. Significant indirect effects were found between immigrant status and victimization. Interpersonal but not intrapersonal risk factors helped to explain these associations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Microwave drying of pine and spruce 总被引:3,自引:0,他引:3
A. L. Antti 《Holz als Roh- und Werkstoff》1995,53(5):333-338
Drying rates and power densities are determined for pine-and sprucewood when dried from green to 8% moisture content by microwave power. The process is controlled by measurements of internal wood temperature, internal vapour pressure and rate of moisture evaporation. Microwave power densities ranged from 25 to 78 kW/m3, microwave energy consumption from 365 to 760 kWh/m3. Internal wood temperatures up to 140 °C were used. Internal vapour pressure in the wood could rise to about 20 kPa without checking. Maximal drying rates of 0.20 to 0.45% moisture content per minute are possible to obtain when drying above fiber saturation (fsp). Below fsp the feasible drying rates ranged from 0.10 to 0.20% moisture content per minute. Spruce dried approximately 1.6 times faster than pine. No conditioning of the wood was necessary since the wood was free of stresses. The wood was free of checks but colour changes occured in the interior of some specimens. 相似文献
68.
Ion Tiseanu Matej Mayer Teddy Craciunescu Antti Hakola Seppo Koivuranta Jari Likonen Cristian Ruset Cosmin Dobrea 《Surface & coatings technology》2011
Tungsten erosion, its subsequent transport and redeposition are of great interest, because a full tungsten divertor is foreseen to be used during the deuterium–tritium operational phase of ITER. The erosion of tungsten and carbon marker layers was extensively studied in the outer divertor of ASDEX Upgrade (AUG), and work is currently in progress to completely replace the existing JET CFC tiles with tungsten-coated tiles within the JET ITER-like wall project. The need for fast and non-destructive method which allows the quantitative determination of the thickness of a tungsten coating on a carbon material on large areas led us to evaluate a combined absorption/fluorescence X-ray (XRTF) technique. The method can provide fast analysis, high spatial resolution and a material selective detection of deposited layers and inclusions. It was applied on W coated fine grain graphite (FGG) tiles from AUG's divertor. It is proved that the method is able to provide information about the uniformity of the tungsten coating on a graphite or CFC substrate whilst the technique can be used to determine the thickness of the tungsten and other marker materials coatings. It represents a unique instrument for the post-mortem analysis of the coatings. 相似文献
69.
Juha Tommila Arto Aho Antti Tukiainen Ville Polojrvi Joel Salmi Tapio Niemi Mircea Guina 《Progress in Photovoltaics: Research and Applications》2013,21(5):1158-1162
We report on the performance of biomimicked antireflection coating applied to dilute nitride solar cell. The coating consists of nanostructures replicating the moth‐eye geometry and has been fabricated by nanoimprint lithography directly within the window layer covering the dilute nitride absorbing junction. The mean reflectivity within the spectral range of 320–1800 nm remains under 5% for incident angles up to 45°. The effect of the coating on the cell performance was assessed by measuring the current–voltage characteristics under simulated solar illumination. A clear performance increase was identified when comparing a solar cell with the moth‐eye coating with a solar cell having a standard SiNx/SiO2 coating. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
70.
Study of the PM Gas-Phase Filter Artifact Using a Setup for Mixing Diesel-Like Soot and Hydrocarbons
Richard Högström Panu Karjalainen Jaakko Yli-Ojanperä Antti Rostedt Martti Heinonen Jyrki M. Mäkelä 《Aerosol science and technology》2013,47(9):1045-1052
The filter artifact is a significant source of error in gravimetric measurements of particulate matter (PM) exhaust. However, only a few studies on the subject exist. Results from these studies show a large discrepancy mainly because the experiments were performed using real diesel vehicle exhaust with varying exhaust composition. In this study, a setup for mixing diesel-like soot and hydrocarbon vapor was constructed for generating a stable exhaust aerosol with adjustable composition. The particle size distribution of the diesel-fueled soot generator (GMD [geometric mean diameter] adjustable between 27 and 164 nm) was found to represent “real” exhaust particulate emission. This setup was applied for studying the filter artifact on Teflon-coated glass fiber filters using pentadecane as the hydrocarbon vapor. Experiments were performed using particle and hydrocarbon concentrations of 130–700 μg/m3 and 10–12 ppm, respectively. It was found that the particle concentration of the aerosol affects the filter artifact. At lower particle concentrations, more hydrocarbon adsorption was detected. In the absence of particles, the adsorption was highest. Furthermore, filter soot load, corresponding to 0.13%–0.66% of the clean filter mass, was found to affect adsorption. Sooty filters adsorbed less vapor than clean filters. However, increasing the soot load resulted in more adsorption. Moreover, it was found that the backup filter serves as a reasonable estimate of the filter artifact only for low particle concentrations and filter soot loads. These results indicate that the filter soot load is an important parameter influencing the filter artifact, and therefore, it should be considered when performing gravimetric sampling. The setup was proven to be a unique tool for quantitative studies of the filter artifact. Copyright 2012 American Association for Aerosol Research 相似文献