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Några fakta om vattenavvisande fasadimpregnering

Sedan 1990 har forskningsprojekt rörande vattenavvisande fasadimpregnering ingått i forskningsprogrammet för Fuktgruppen vid Lunds Tekniska Högskola. Projekten har finansierats av Svenska Byggbranschens Utvecklingsfond, SBUF.

Migratory blackcaps can use their magnetic compass at 5 degrees inclination, but are completely random at 0 degrees inclination

It is known that night-migratory songbirds use a magnetic compass measuring the magnetic inclination angle, i.e. the angle between the Earth's surface and the magnetic field lines, but how do such birds orient at the magnetic equator? A previous study reported that birds are completely randomly oriented in a horizontal north-south magnetic field with 0° inclination angle. This seems counter-intuit

Nytt cement med gynnsam miljöprofil

Dagens cement för konstruktionsändamål baseras på portlandklinker. Utgångsmaterialet är kalksten som bränns vid hög temperatur i cementugn. Processen är energikrävande samtidigt som stora mängder koldioxid drivs ut ur kalkstenen och ur bränslet. Koldioxidutsläppet från världens totala cementproduktion anses uppgå till cirka fem procent av alla koldioxidutsläpp globalt.

Coalitions, Coordination and Electoral Choice : A Lab Experimental Study of Strategic Voting

When a voter chooses between large and small parties in a coalition, strategic reasons may be the tie-breaker. “Strategic voting” is often defined as a vote for another party than one’s most preferred one with the intention to affect the outcome of the election. The presence of coalitions can sometimes be argued to lead to less strategic voting, whereas others claim that coalitions create more str

Flight of the dragonflies and damselflies

This work is a synthesis of our current understanding of the mechanics, aerodynamics and visuallymediated control of dragonfly and damselfly flight, with the addition of new experimental and computational data in several key areas. These are: the diversity of dragonfly wing morphologies, the aerodynamics of gliding flight, force generation in flapping flight, aerodynamic efficiency, comparative fl

Optimization of the short-circuit current in an InP nanowire array solar cell through opto-electronic modeling

InP nanowire arrays with axial p-i-n junctions are promising devices for next-generation photovoltaics, with a demonstrated efficiency of 13.8%. However, the short-circuit current in such arrays does not match their absorption performance. Here, through combined optical and electrical modeling, we study how the absorption of photons and separation of the resulting photogenerated electron-hole pair

Sufficient Reasons to Act Wrongly : Making Parfit’s Kantian Contractualist Formula Consistent with Reasons

In On What Matters (2011) Derek Parfit advocates the Kantian Contractualist Formula as one of three supreme moral principles. In important cases, this formula entails that it is wrong for an agent to act in a way that would be partially best. In contrast, Parfit’s wide value-based objective view of reasons entails that the agent often have sufficient reasons to perform such acts. It seems then tha

Structural topology optimization of multibody systems

Flexible multibody dynamics (FMD) has found many applications in control, analysis and design of mechanical systems. FMD together with the theory of structural optimization can be used for designing multibody systems with bodies which are lighter, but stronger. Topology optimization of static structures is an active research topic in structural mechanics. However, the extension to the dynamic case

The Co-Structure Directing Agent (CSDA) Approach to Mesoporous Silica Formation – Exploring the Assembly Characteristics

This thesis is focused on the detail process of formation of mesoporous silica materials.Mesoporous silica materials are one type of porous materials with a pore size between 2 and 5 nm (1 nm=0.000 000 001 m). The pore walls consist of silicon dioxide – silica (sand also consists of silica). The mesoporous silica materials are formed by amphiphilic molecules, a kind of molecule with one part that We investigate the formation mechanism responsible for two specific systems of mesoporous silicas formed with the so-called co-structure directing agent (CSDA) route. The synthesis relies on the interactions between silica source (tetraethylorthosilicate, TEOS), surfactants and CSDA. The structures of the mesoporous silica materials were investigated mainly by small angle X-ray diffraction (SAXD),

Swedish regional GDP 1855-2000 Estimations and general trends in the Swedish regional system

This paper uses a method devised by Geary and Stark to estimate regional GDPs for 24 Swedish provinces 1855-2007. In empirical tests, we find that the Swedish estimations yield results of good precision, comparable to those reported in the international literature. From the literature, we generate six expectations concerning the development of regional GDPs in Sweden. Using the GDP estimations, we