Biomass fired small-scale CHP in Sweden and the Baltic States: a case study on the potential of clustered dwellings

Sweden as well as the three Baltic states has an abundant supply of biomass, mostly wood waste. Much of it goes into district heating (DH), which has expanded continuously since the first system started 50 years ago. DH now accounts for 43% of the heating consumption and a further expansion is possible in many directions. Firstly existing DH systems can be enlarged, secondly DH can be upgraded to combined heat and power (CHP) to a much larger extent, thirdly new DH (and CHP) systems can be implemented in many smaller places down to 1000 inhabitants or less. The last alternative, biomass and especially pellets fired small-scale cogeneration in combination with local heating networks, is the topic for this paper. It presents a method to estimate the potential for small-scale DH and CHP and results from a “test” area in southeast Sweden. The method estimates local heat demand using databases with individual and statistical property data. It identifies areas with clusters of buildings where the heat demand is enough to implement decentralized small DH networks if possible in combination with small-scale CHP. In the event for Swedish circumstances very sparsely populated test area of 36×48 km² with around 8000 inhabitants, the total heat consumption in residential buildings is estimated to 84 GW h. When we have identified the areas with clusters of buildings, we have set the minimum heat consumption in such an area to 500 MW h. The area size is varied in 250 m steps from 250×250 m² to 1000×1000 m². For the four area sizes, the method then identifies and locates 30, 38, 38,30, respectively, clustered areas with a potential for small-scale DH and CHP worth investing closer.     

Software zur Verpackungslogistik

Zusammenfassung Der vorliegende Beitrag stellt die Ergebnisse eines Vergleichs von Software zur Verpackungslogistik vor. Es werden vier Programmpakete gegenübergestellt, die von deutschen bzw. englischen Firmen derzeit angeboten werden.     

Revisiting the microstructure of hydrated tricalcium silicate––a comparison to Portland cement

The microstructures of 0.40 w/s-ratio pastes of tricalcium silicate (C₃S), alite and Portland cement have been studied at the hydration times 24 h and 1 month. A field-emission SEM (FE-SEM) was used to obtain high-resolution backscattered electron images. Comparison revealed no microstructural differences between C₃S and alite, but there were considerable differences in microstructure between C₃S and Portland cement pastes. The microstructure of the C₃S paste was simpler than that of the Portland cement, and could be described by a few characteristic features. Distribution of the reaction products differed substantially in the two systems. While hollow shells (Hadley grains) were a prominent feature of the Portland cement paste, their occurrence was more limited in the C₃S and alite pastes. Hollow shells were restricted to grains smaller than about 5 μm in the C₃S and alite pastes, and gapped hollow shells were not a common feature.     

Die Innovationstätigkeit der deutschen Softwareindustrie

In this article we present the results of two empirical studies focusing on the structure and extent of the innovation activities of the German Software Industry and analyze distinctive features of Software Innovations. We distinguish the activities of the primary (core) Software Industry and secondary industries such as Mechanical and Electrical Engineering, Motor Industry and Telecommunications. A special focus is put on the question if innovations in Software are sequential, on the role of Open Source Software and the importance of interoperability.     

Modeling recrystallization kinetics,grain sizes,and textures during multipass hot rolling

A physically based model for the evolution of recrystallization microstructures and textures during hot rolling of aluminum is presented. The approach taken differs from similar models developed for steels. The present model is based on recent experimental investigations directed toward identifying the nature of the nucleation sites for recrystallized grains of different crystallographic orientations. Particle stimulated nucleation (PSN) and nucleation from cube bands and grain boundary regions have been incorporated in the model. The multipass aspect complicates the modeling due to partial recrystallization between the rolling passes. Two different approaches have been suggested to handle this. The model has been applied to predictions of recrystallization kinetics, recrystallized grain sizes, and recrystallization textures during multipass hot rolling of aluminum. The predictions are reasonable compared to experimental results.     

Rat strain differences in copulatory behavior after para-chlorophenylalanine and hormone treatment.

The potentiation of masculine copulatory behavior in castrated male rats following systemic parachlorophenylalanine (PCPA) treatment was found to be dependent upon the strain of rat and the recency of castration. Wistar (W) and Sprague-Dawley (SD) males displayed a decline in behavioral responsiveness to PCPA treatment following castration, the Ws retaining their behavioral responsiveness longer than SDs. Castrated Ws were also behaviorally more responsive to androgen replacement than were SDs. Ovariectomized W and SD females receiving estrogen replacement displayed a strain difference in hormonal sensitivity. In tests for feminine copulatory behavior, ovariectomized Ws were behaviorally more sensitive to estrogen treatment than SDs. Ovariectomized and estrogen-primed females of both strains displayed potentiated lordotic behavior following chronic PCPA treatment. Concomitant treatment with dexamethasone to reduce adrenal steroid output abolished the potentiation of lordotic behavior found with PCPA treatment. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modelling aspects for finite element analysis of ship vibration

The paper describes the present state-of-the-art in analyses of ship vibration and elaborates on the difficulties regarding the finite element modelling.Some suggestions to enable better modelling of the structure, dependent on the aims of the analyses, the accuracy of input data, time and cost are given.It is shown that the main resonant frequencies of global and local structures may be predicted with sufficient accuracy, and a good indication of the forced response level may be obtained at the design stage.     

Vergleichende Untersuchung der anatomischen und physikalischen Eigenschaften des Holzes vonPopulus Simonii undPopulus robusta

Zusammenfassung Vergleichend-anatomische Untersuchungen des Holzes vonPopulus Simonii undPopulus robusta ergaben, da? die besten Unterscheidungsmerkmale für diese beiden Pappelarten Unterschiede in den Markstrahlh?hen und im Reichtum an Strangparenchym sind. Auf Grund der vergleichend-physikalischen Untersuchung wird das Holz vonP. robusta als “ziemlich schwer”, das Holz vonP. Simonii als “mittelschwer” befunden. BeiP. Simonii besteht au?erdem eine Beziehung zwischen Rohwichte und Raumschwindung. Die Schwindung im Splint der Balsampappel ist wesentlich geringer als diejenige beiP. robusta.

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Comparative study on the anatomical and physical properties of wood ofPopulus Simonii andPopulus robusta

Summary Comparative anatomical studies on the wood of Populus Simonii and Populus robusta proved that their differences in ray height and richness in parenchyma are the most reliable characteristics for the distinction of these two poplar species. According to the results of comparative physical investigations the wood of P. robusta is designated as “rather heavy”, the wood of P. Simonii is found to be of “medium weight”. In the case of P. Simonii there is also a relationship between density and volume shrinkage. The shrinkage in the sapwood of balsam-poplar is considerably less than that of P. robusta.