Sökning: "periodic replacement"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden periodic replacement.

  1. 1. Decision support models for the maintenance and design of mill liners

    Författare :Rajiv Dandotiya; Saleh Duffuaa; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Drift och underhållsteknik; Operation and Maintenance;

    Sammanfattning : Mining companies use heavy-duty equipment that work round the clock in highly abrasive environments. Autogenous (AG) mills used in the mining industry and in ore dressing plants are examples of major bottlenecks in the context of downtime and exert an influence on production economics. LÄS MER

  3. 2. In pursuit of next generation photovoltaics : An electronic structure study of lead-free perovskite solar cells

    Författare :Axel Erbing; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; teoretisk fysik; Theoretical Physics;

    Sammanfattning : The recent development of perovskite-based solar cells have shown a remarkably fast increase in power conversion efficiency making them a promising low-cost alternative to conventional cells. The most successful class of materials however, the lead-halide perovskites, are held back due to toxicity and stability issues significantly limiting their use. LÄS MER

  4. 3. Production and biomedical use of non-conventional positron emitters

    Författare :Vladimir Tolmachev; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Oncology; Onkologi; Oncology; Onkologi; Biomedical Radiation Science; biomedicinsk strålningsvetenskap;

    Sammanfattning : Positron Emission Tomography (PET) is a powerful diagnostic tool. So far, it has mainly been associated with the use of short-lived positron emitters with half-lives shorter than 2 h, like 11C and 18F. LÄS MER

  5. 4. Catalytic Water Production from First-Principles Calculations

    Författare :Gustav Karlberg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; platinum; Monte Carlo; first-principles; hydroxyl; transition metals; density functional theory DFT ; Metropolis; oxygen; water; water production reaction; hydrogen;

    Sammanfattning : The main subject of this thesis is the catalytic water production reaction on metal surfaces. This reaction is of great current interest due to its importance in fuel cells, a clean and efficient way to convert chemical energy into electrical. LÄS MER

  7. 5. Sleep Related Movement Disorders : Association with Menopause and Pregnancy

    Författare :Jan Wesström; Inger Sundström-Poromaa; Jan Ulfberg; Staffan Nilsson; Päivi Polo; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Sleep; Restless Legs Syndrome; Women; Menopause; Pregnancy; Depression; Medicin; Medicine;

    Sammanfattning : It is known that sleep problems affect people’s wellbeing and has great consequences for public health.Restless legs syndrome (RLS) gives uncomfortable sensations in the legs at rest, leading to an irresistible need for activity. It aggravates in evening and at night. LÄS MER