Sökning: "pebbles"

Visar resultat 1 - 5 av 16 uppsatser innehållade ordet pebbles.

  1. 1. Aspects of erosion of restored trout spawning beds in two streams in Northern Sweden

    Master-uppsats, SLU/Dept. of Wildlife, Fish and Environmental Studies

    Författare :Frida Michelle Granlund; [2021]
    Nyckelord :in-stream restoration; reproductive habitat; salmonids; passive integrated transponders tags PIT-tags ;

    Sammanfattning : Many rivers and streams in northern Sweden have been channelized due to timber floating. This has severely degraded the spawning habitats for salmon and trout, and therefore a common action when restoring channelized rivers is to establish new spawning beds by adding gravel to the streambed. LÄS MER

  2. 2. How did Jupiter form?

    Kandidat-uppsats, Lunds universitet/Astronomi

    Författare :Calle Ahlgren; [2019]
    Nyckelord :Planet formation; Planet migration; Physics and Astronomy;

    Sammanfattning : Two relatively new concepts in planetary science are planetary migration; wherein the planets migrate through the protoplanetary disk as they form, and pebble accretion; wherein the planetesimals which become terrestrial planets and giant planet cores grow through the accretion of small pebbles. Planetary migration has become a generally accepted concept but there is still much to be learned even about how it affected the formation of our own solar system. LÄS MER

  3. 3. The fate of pebbles and planetesimals entering protoplanetary envelopes

    Master-uppsats, Lunds universitet/Astronomi

    Författare :Emil Zadera; [2019]
    Nyckelord :Planet formation; planet; protoplanet; protoplanetary envelope; protoplanetary atmosphere; protoplanetary growth; planetary growth model; accretion rate; vapour blob; vapourblob; vapour planet; transport of water; water on planet; pebbles; planetesimals; pebble accretion; planetesimal accretion; meteors; ablation; fragmentation; sublimation; protoplanetary disk; MMSN; accretion window; accretion channel; accretion; destruction; disruption; terminal velocity; gas; gasflow; shearingbox; exoplanet; Physics and Astronomy;

    Sammanfattning : Planetary embryos grow by the accretion of solid dust-material, ranging from cm- to m-sized pebbles up to km-sized planetesimals. However, the underlying size-distribution of the accreted material is poorly understood. LÄS MER

  4. 4. Formation and Evolution of Protoplanetary Disks

    Master-uppsats, Lunds universitet/Astronomi

    Författare :Johan Appelgren; [2019]
    Nyckelord :protoplanetary disk; protoplanetary disk formation; protoplanetary disk evolution; planet formation; Physics and Astronomy;

    Sammanfattning : A star forms with a surrounding protoplanetary disk after the collapse of a molecular cloud core. Subsequently, over a period of several Myr this protoplanetary disk of dust and gas is accreted onto the host star. We model the formation and evolution of such a protoplanetary disk using a one-dimensional numerical model. LÄS MER

  5. 5. Kring Stenarna - En lägerskola i tegel

    Master-uppsats, Lunds universitet/Institutionen för arkitektur och byggd miljö

    Författare :Oskar Wallin; [2018]
    Nyckelord :Arts and Architecture;

    Sammanfattning : When you first step ashore the island of Ven, in Öresund right between Sweden and Denmark, you have two options. Either you go straight ahead, towards the bike rental, or you turn to your right and start walking along the shore. If you do so, you will soon start to find colourful pebbles on the ground along the waterline. LÄS MER