Search results for "kalorimetria"
showing 5 items of 5 documents
Thermal, spectroscopic and crystallographic analysis of mannose-derived linear polyols
2018
The major diastereomer formed in the Barbier-type metal-mediated allylation of D-mannose has previously been shown to adopt a perfectly linear conformation, both in solid state and in solution, resulting in the formation of hydrogen-bonded networks and subsequent aggregation from aqueous solution upon stirring. Here, a comprehensive study of the solid state structure of both the allylated D-mannose and its racemic form has been conducted. The binary melting point diagram of the system was determined by differential scanning calorimetry analysis, and the obtained results, along with structure determination by single crystal X-ray diffraction, confirmed that allylated mannose forms a true rac…
Superconductor-ferromagnet tunnel junction thermoelectric bolometer and calorimeter with a SQUID readout
2020
Superconductor-ferromagnet thermoelectric detector (SFTED) is a novel ultrasensitive radiation detector based on the giant thermoelectric effect in superconductor-ferromagnet tunnel junctions. This type of detector can be operated without the need of additional bias lines, and is predicted to provide a performance rivaling transition-edge sensors and kinetic inductance detectors. Here we report our numerical studies on the SFTED noise equivalent power, energy resolution and time constant, and the feasibility of a SQUID readout in both bolometric and calorimetric regimes, with the goal to provide practical design parameters for the detector fabrication and the readout circuitry implementatio…
Specific heat of thin phonon cavities at low temperature: Very high values revealed by zeptojoule calorimetry
2022
The specific heat of phonon cavities is investigated in order to analyze the effect of phonon confinement on thermodynamic properties. The specific heat of freestanding very thin SiN membranes in the low-dimensional limit is measured down to very low temperatures (from 6 K to 50 mK). In the whole temperature range, we measured an excess specific heat orders of magnitude bigger than the typical value observed in amorphous solids. Below 1 K, a crossover in cp to a lower power law is seen, and the value of the specific heat of thinner membranes becomes larger than that of thicker ones demonstrating a significant contribution coming from the surface. We show that this high value of the specific…
Analytical models for the pulse shape of a superconductor-ferromagnet tunnel junction thermoelectric microcalorimeter
2022
AbstractThe superconductor-ferromagnet thermoelectric detector (SFTED) is a novel ultrasensitive radiation detector based on the giant thermoelectric effect in superconductor-ferromagnet tunnel junctions. We demonstrate analytical models and solutions in the time domain for a SFTED operated as a microcalorimeter (pulse excitation), in the linear small-signal limit. Based on these solutions, the signal current and temperature pulse response were studied for two different electrical circuit models, providing design conditions for stable and non-oscillatory response.Kindly check and confirm whether the corresponding author is correctly identified.The corresponding author is correct.
Lepoaineenvaihdunnan määrittäminen epäsuoralla kalorimetrialla ja naisurheilijan oireyhtymä
2018
Johdanto. Epäsuora kalorimetria on yleinen tapa määrittää lepoaineenvaihdunta (LAVESK). Tarkoituksena on tutkia LAVESK:n toistettavuutta ja pätevyyttä kannettavalla hengityskaasuanalysaattorilla määritettynä. Tutkimuksen toisessa osassa tutkitaan antropometristen ja hormonaalisten muuttujien yhteyttä lepoaineenvaihduntaan naiskestävyysjuoksijoilla. Naisurheilijan oireyhtymässä alhainen energiansaatavuus, kuukautiskierron häiriöt sekä alentunut luuston massa yhdistyvät toisiinsa. Alhainen energiansaatavuus on yhteydessä adaptiiviseen termogeneesiin, jolloin havaitaan muutoksia myös lepoaineenvaihdunnassa. Menetelmät. LAVESK:n toistettavuuden osalta aineisto koostuu terveistä nuorista aikuisi…