Sökning: "carbon"
Visar resultat 21 - 25 av 3420 avhandlingar innehållade ordet carbon.
21. Impacts of global change on primary production in northern lakes
Sammanfattning : Algae are primary producers, a major component of the aquatic foodweb, and changes in primary production affect aquatic ecology in general. Global changes such as warming, recovery of acidification and changes in land-use have caused warming and browning of northern lakes. LÄS MER
22. Northern Permafrost Region Soil Carbon Dynamics since the Last Glacial Maximum : a terrestrial component in the glacial to interglacial carbon cycle
Sammanfattning : At the Last Glacial Maximum (LGM), after ~100,000 years of relatively cold temperatures and progressively lower atmospheric carbon dioxide (CO2) concentrations, CO2 levels reached ~180 ppm, which is less than half of what we see today in a much warmer world (~400 ppm). Although much of this increase since the LGM is due to human-induced emissions, about 100 ppm of this increase can be attributed to natural variations seen over glacial to interglacial cycles. LÄS MER
23. Toward Carbon based NEMS
Sammanfattning : A systematic analysis and assessment of carbon nanotube (CNT) based NEMS switches is presented and their features are compared to typical complementary metal-oxide-semiconductor (CMOS) performance parameters. It is shown that CNT-based switches with considerably smaller leakage current compared to CMOS switches can be realized. LÄS MER
24. Cellulose derived carbon dots : From synthesis to evaluation as multifunctional building blocks in biomedical scaffolds
Sammanfattning : The implementation of biobased and biodegradable polymeric materials in biomedical applications is often coupled with issues related to their insufficient mechanical properties or limited bioactivity. In this thesis, a perspective on valorization of biomass is presented, demonstrating the transformation of cellulose into biobased carbon nanomaterials with the potential to serve as multifunctional property enhancers in polycaprolactone (PCL) scaffold materials for tissue engineering. LÄS MER
25. Carbon-nanotube-based nanoelectromechanics
Sammanfattning : Carbon nanotubes, a novel material with extraordinary mechanical and electrical properties, are good candidates for designing nanoelectromechanical systems. The typical length scale of these systems is nanometers and an important characteristic is a coupling between electrical and mechanical degrees of freedom. LÄS MER