Sökning: "pulse"

Visar resultat 21 - 25 av 878 avhandlingar innehållade ordet pulse.

1. 21. Ultra-intense laser-plasma interaction for applied and fundamental physics

   Författare :Arkady Gonoskov; Mattias Marklund; Gert Brodin; Vladimir Tikhonchuk; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ultra-intense laser; femtosecond pulse; plasma; relativistic phenomena; laser-driven acceleration; attosecond pulse generation; radiation reaction; fysik; Physics;

   Sammanfattning : Rapid progress in ultra-intense laser technology has resulted in intensity levels surpassing 1022 W/cm2, reaching the highest possible density of electromagnetic energy amongst all controlled sources available in the laboratory. During recent decades, fast growth in available intensity has stimulated numerous studies based on the use of high intensity lasers as a unique tool for the initiation of nonlinear behavior in various basic systems: first molecules and atoms, then plasma resulting from the ionization of gases and solids, and, finally, pure vacuum. LÄS MER

3. 22. Exploring the Possibilities of 14C Bomb-Pulse Dating of Human Tissue Samples

   Författare :Elisavet Georgiadou; Kärnfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 14C measurements; Bomb-pulse dating; human body; serum; plaque; Fysicumarkivet A:2014:Georgiadou;

   Sammanfattning : The testing of nuclear weapons in the atmosphere, in the middle of the 20'h century, resulted in a bomb-pulse excess of atmospheric 14C. A bomb-pulse dating method was thus developed. The latter is a method to determine the time of formation of formerly living modern (i.e. LÄS MER

4. 23. Exploring the limitations of 14C bomb-pulse dating on human tissue samples

   Författare :Elisavet Georgiadou; Kärnfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bomb-pulse dating; human tissues; stable isotope analysis;

   Sammanfattning : The aim of this work, which will be part of the PhD work of the author of this report, was to evaluate the precision and accuracy expected from bomb-pulse dating of human tissue, focusing on the uncertainties introduced by variation in 14C in the human diet. Such variations may be caused by releases from nuclear installations, hospitals and laboratories using 14C, use of fossil fuels as well as variations in the type of diet consumed (e. LÄS MER

5. 24. Radiofrequenz-Pulse in der lokalisierten STEAM-Spektroskopie

   Författare :Gunther Helms; Lund Medicinsk strålningsfysik; []
   Nyckelord :;

   Sammanfattning : By definition, radiofrequency (RF) pulses are the pivotal elements of NMR pulse sequences. Vice versa, the effect of a particular pulse on the evolution of magnetization will depend on the context of the sequence. LÄS MER

7. 25. Measurements in Idiopathic Normal Pressure Hydrocephalus : Computerized neuropsychological test battery and intracranial pulse waves

   Författare :Anders Behrens; Jan Malm; Anders Eklund; Eva Elgh; Niklas Lenfeldt; Marianne Juhler; Umeå universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Hydrocephalus; Normal Pressure; Neuropsychological tests; Neuropsychology; Reliability and validity; Software; Dementia; intracranial pressure; spinal puncture; cerebrospinal fluid pressure; pulse pressure waves; Blood flow velocity; Middle cerebral artery; Pulsatility index; Neurology; neurologi;

   Sammanfattning : Idiopathic Normal Pressure Hydrocephalus (INPH) is a condition affecting gait, cognition and continence. Radiological examination reveals enlarged ventricles of the brain. A shunt that drains CSF from the ventricles to the abdomen often improves the symptoms. LÄS MER