Sökning: "thermal aging"

Visar resultat 6 - 10 av 27 uppsatser innehållade orden thermal aging.

  1. 6. Lifetime prediction of a polymeric propellant binder using the Arrhenius approach

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Tillämpad materialvetenskap

    Författare :Johannes Bohlin; [2021]
    Nyckelord :Polymer; Thermal-oxidative degradation; Lifetime prediction; Propellant; Arrhenius; Aging experiments; Diffusion-limited oxidation;

    Sammanfattning : The thermal-oxidative degradation of a crosslinked hydroxy-terminated polybutadiene (HTPB)/cycloaliphatic diisocyanate (H12MDI) based polymer, which is commonly used as a polymeric binder in propellants, is investigated at temperatures from 95°C to 125°C with the aim of estimating the lifetime of the material in storage conditions (20°C) using the Arrhenius approach. Furthermore, the effect of antioxidants and to a lesser extent plasticizer on the degradation process was also studied. LÄS MER

  3. 7. Övervakning av kapacitetsbegränsningar i kraftsystemet

    Kandidat-uppsats, Högskolan Väst/Avdelningen för Industriell ekonomi, Elektro- och Maskinteknik

    Författare :Jonas Leander Nilsson; [2021]
    Nyckelord :Elkraft; övervakning;

    Sammanfattning : Det här examensarbetet genomförs med Vattenfall Eldistribution som uppdragsgivare. Parter inom företaget anser att driftövervakningen idag sker aningen konservativt och traditionsbundet. LÄS MER

  4. 8. Evaluation of alternative, sustainable polymer materials in regard to mechanical properties and sustainability

    Master-uppsats, Lunds universitet/Centrum för analys och syntes

    Författare :Hanna Axelsson; Joaquin Rudervall; [2021]
    Nyckelord :sustainability; polymers; LCA; mechanical properties; testing; biobased; plastic; recycled; polymer technology; Technology and Engineering;

    Sammanfattning : We live in a world where products are consumed at an ever increasing rate, and where responsibility for the waste created is seldom taken. Plastics are in many ways wondrous materials, but they put a big strain on the environment, both in production and as waste. LÄS MER

  5. 9. Bearing condition monitoring : An investigation on the possibility of monitoring aging of the lubricating grease by means of acoustic emission and temperature.

    Master-uppsats, Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

    Författare :Dilesh Raj Shrestha; [2021]
    Nyckelord :Acoustic Emission; Fourier Transform; Infrared Spectroscopy; Condition Monitoring; Total Acidic Number; Fast Fourier Transform; Scanning Electron Microscopy; Rheology; Bleed Oil; Grease degradation;

    Sammanfattning : Grease is among the most widely used lubricants in rolling element bearings. Proper understanding of the effect of lubrication due to grease aging can provide a significant increase in the life of the engineering systems. However, at present, there is no sufficient understanding of the grease aging effect in rolling elements bearing. LÄS MER

  7. 10. Thermal induced yellowing of peroxide bleached birch pulp

    Uppsats för yrkesexamina på avancerad nivå, Luleå tekniska universitet/Industriell miljö- och processteknik

    Författare :Alexander Nygren; [2020]
    Nyckelord :Accelerated ageing; Bleaching; Brightness reversion; Kraft pulp; pH; Yellowing;

    Sammanfattning : Brightness reversion, also known as yellowing, is a well-known phenomenon which means that the brightness of paper products decreases during ageing. The name of this phenomenon is based on that paper products usually change in color towards yellow during ageing. LÄS MER