Glykolivesien ohjausjärjestelmän järjestelmäkuvaus

Tämä insinöörityö toteutettiin Helsinki-Vantaan lentoasemaa hallinnoivalle Finavia Oyj:lle. Työn tavoitteena oli selvittää lentokentän hulevesien ohjausjärjestelmän toimintaa ja luoda siitä Finavian käyttöön selkeät dokumentit toimintaselostuksineen. Luotua materiaalia voidaan käyttää järjestelmää tuntemattomien henkilöiden perehdyttämiseen sekä pohjamateriaalina mahdollisille järjestelmän muutostöille tulevaisuudessa. Lentokoneiden jäänestoaineena käytetään propyleeniglykolia, jonka ympäristöä kuormittavien ominaisuuksien takia sitä ei ole suotavaa johtaa luontoon lentoaseman hulevesien mukana. Lentoaseman suuren pinta-alan vuoksi hulevesien muodostuminen on ajoittain hyvin runsasta. Huleveden ohjaus prosessissa ja sen loppusijoittaminen riippuvat sen laadusta ja glykolipitoisuudesta. Työn aluksi selvitettiin ja listattiin kaikki hulevesien hallintaan liittyvät prosessit ja kiinteistönumerot. Jokaiseen saavutettavissa olevaan kohteeseen käytiin tutustumassa prosessiin ja sen laitteistoon luoden muistiinpanoja. Myös asiantuntijoita haastateltiin. Kohteista laadittiin säätökaaviot sekä toimintaselostukset muistiinpanojen ja jo olemassa olleiden dokumenttien perusteella. Tämän insinöörityön tuloksena saatiin Finavian käyttöön kirjallinen yhteenveto jäänpoisto- ja -estokäsittelyiden vaikutuksesta hulevesien hallintaan Helsinki-Vantaan lentoasemalla sekä prosessikohtaiset säätökaaviot lyhyine toimintaselostuksineen.This thesis was made for Finavia plc., which maintains and manages the Helsinki Airport. The goal of this thesis was to research the control systems of runoff waters at Helsinki airport and create documents with diagrams and descriptions. The created documents can be used for briefing new people and for base information when the system is developed further. The used chemical for airplane de-icing and anti-icing procedures is propylene glycol which burdens the environment. This is why the runoff waters of Helsinki airport are controlled. The large area of Helsinki airport creates a lot of urban runoff waters. The controlling and destination of runoff waters depends on its quality. The first step in this study was to investigate all the processes and properties related to control system of runoff waters. All the process-related properties were visited and equipment reviewed, based on which notes were made. Specialists were also interviewed. Every part of the processes was documented with diagrams and descriptions. As a result of this thesis a compact research of the effects of de-icing and anti-icing procedures for controlling the runoff waters was created. The thesis contains diagrams and descriptions of every part of the processes

Electron-phonon coupling reflecting dynamic charge inhomogeneity in copper-oxide superconductors

The attempt to understand cuprate superconductors is complicated by the presence of multiple strong interactions. While many believe that antiferromagnetism is important for the superconductivity, there has been revived interest in the role of electron-lattice coupling. The recently studied conventional superconductor MgB2 has a very strong electron-lattice coupling, involving a particular vibrational mode (phonon), that was predicted by standard theory and confirmed quantitatively by experiment. Here we present inelastic scattering measurements that show a similarly strong anomaly in the Cu-O bond-stretching phonon in the cuprate superconductors La2-xSrxCuO4 (with x=0.07, 0.15). This is in contrast to conventional theory, which does not predict such behavior. The anomaly is strongest in La1.875Ba0.125CuO4 and La1.48Nd0.4Sr0.12CuO4, compounds that exhibit spatially modulated charge and magnetic order, often called stripe order. It occurs at a wave vector corresponding to the charge order. These results suggest that this giant electron-phonon anomaly, which is absent in undoped and over-doped non-superconductors, is associated with charge inhomogeneity. It follows that electron-phonon coupling may be important to our understanding of superconductivity, although its contribution to the mechanism is likely to be indirect.Comment: to appear in Nature, 16 pages, 4 figures, very minor changes in text and figures from previous versio

Carbon-depleted outer core revealed by sound velocity measurements of liquid iron-carbon alloy

The relative abundance of light elements in the Earth's core has long been controversial. Recently, the presence of carbon in the core has been emphasized, because the density and sound velocities of the inner core may be consistent with solid Fe(7)C(3). Here we report the longitudinal wave velocity of liquid Fe(84)C(16) up to 70 GPa based on inelastic X-ray scattering measurements. We find the velocity to be substantially slower than that of solid iron and Fe(3)C and to be faster than that of liquid iron. The thermodynamic equation of state for liquid Fe(84)C(16) is also obtained from the velocity data combined with previous density measurements at 1 bar. The longitudinal velocity of the outer core, about 4% faster than that of liquid iron, is consistent with the presence of 4–5 at.% carbon. However, that amount of carbon is too small to account for the outer core density deficit, suggesting that carbon cannot be a predominant light element in the core

Momentum-resolved lattice dynamics of parent and electron-doped Sr2IrO4

The mixing of orbital and spin character in the wavefunctions of the 5d iridates has led to predictions of strong couplings between their lattice, electronic and magnetic degrees of freedom. As well as realising a novel spin-orbit assisted Mott-insulating ground state, the perovskite iridate Sr2IrO4 has strong similarities with the cuprate La2CuO4, which on doping hosts a charge density wave that appears intimately connected to high-temperature superconductivity. These phenomena can be sensitively probed through momentum-resolved measurements of the lattice dynamics, made possible by meV-resolution inelastic x-ray scattering. Here we report the first such measurements for both parent and electron-doped Sr2IrO4. We find that the low-energy phonon dispersions and intensities in both compounds are well described by the same non-magnetic DFT calculation. In the parent compound, no changes of the phonons upon magnetic ordering are discernible within the experimental resolution, and in the doped compound no anomalies are apparent due to charge density waves. These measurements extend our knowledge of the lattice properties of (Sr1-xLax)2IrO4, and constrain the couplings of the phonons to magnetic and charge order