Analysis and improvement of the envelope, heating and ventilation of a low energy building with district heating

In this thesis project, a building in Vegagatan 12, Gävle has been analysed in order to see why it does consume more energy than it was expected. This building is a low energy building certified by Miljöbyggnad and it should use less than 55kWh/m2 year and nowadays it is using 62.23 kWh/m2. To get the needed data, some information about the building has been gathered, some measurements have been done in the building and some calculations have been done with those measurements. Finally, some possible solutions have been offered to reduce the energy use of the building. Insulating the floor, the pipes and the walls, reducing the indoor temperature in winter... All of these changes need the help of environmentally friendly attitudes, which is a very important fact in low energy buildings.

Energy and information in Hodgkin-Huxley neurons

[EN]The generation of spikes by neurons is energetically a costly process and the evaluation of the metabolic energy required to maintain the signaling activity of neurons a challenge of practical interest. Neuron models are frequently used to represent the dynamics of real neurons but hardly ever to evaluate the electrochemical energy required to maintain that dynamics. This paper discusses the interpretation of a Hodgkin-Huxley circuit as an energy model for real biological neurons and uses it to evaluate the consumption of metabolic energy in the transmission of information between neurons coupled by electrical synapses, i.e., gap junctions. We show that for a single postsynaptic neuron maximum energy efficiency, measured in bits of mutual information per molecule of adenosine triphosphate (ATP) consumed, requires maximum energy consumption. For groups of parallel postsynaptic neurons we determine values of the synaptic conductance at which the energy efficiency of the transmission presents clear maxima at relatively very low values of metabolic energy consumption. Contrary to what could be expected, the best performance occurs at a low energy cost.

Photorelease of Pyridyl Esters in Organometallic Ru(II) Arene Complexes

New Ru(II) arene complexes of formula [((6)-p-cym)Ru(N-N)(X)](2+) (where p-cym = para-cymene, N-N = 2,2'-bipyrimidine (bpm) or 2,2'-bipyridine (bpy) and X = m/p-COOMe-Py, 1-4) were synthesised and characterized, including the molecular structure of complexes [((6)-p-cym)Ru(bpy)(m-COOMe-Py)](2+) (3) and [((6)-p-cym)Ru(bpy)(p-COOMe-Py)](2+) (4) by single-crystal X-ray diffraction. Complexes 1-4 are stable in the dark in aqueous solution over 48 h and photolysis studies indicate that they can photodissociate the monodentate m/p-COOMe-Py ligands selectively with yields lower than 1%. DFT and TD-DFT calculations (B3LYP/LanL2DZ/6-31G**) performed on singlet and triplet states pinpoint a low-energy triplet state as the reactive state responsible for the selective dissociation of the monodentate pyridyl ligands.