Search results for "Thermometer"

DEEP RESERVOIR TEMPERATURES OF LOW-ENTHALPY GEOTHERMAL SYSTEMS IN TUNISIA: NEW CONSTRAINTS FROM CHEMISTRY OF THERMAL WATERS

2012

Tunisia is characterized by hot and warm groundwaters (temperature up to 75 °C) which represent the surface manifestation of geothermal systems hosted in carbonate-evaporite rock sequences. The T-conditions of Tunisia deep thermal reservoirs are here evaluated for the first time at the regional scale. The results here shown clearly highlight the limitations inherent in the application of common geothermometric methods in the estimation of equilibrium temperatures in sedimentary environments. The modeling approach proposed by Chiodini et alii (1995), which makes use of the ratios between dissolved HCO3, SO4 and F, provides the most reliable results, and allows us to derive equilibrium temper…

Coulomb blockade thermometry

1996

One dimensional arrays of normal metal tunnel junctions have been found to exhibit properties which are very suitable for primary and secondary thermometry in a lithographically adjustable temperature range which extends over about two decades. The thermometer is remarkably insensitive to nonuniformities in the actual pattern and to even strong magnetic fields. We also discuss the behaviour of this device at very low temperatures where the hot electron effect due to poor electron phonon coupling ultimately takes over and at very high temperatures where the finite tunnel barrier effects appear. Short arrays, and especially single tunnel junctions show interesting deviations from the universa…

IV-Curves of tunnel junction arrays at lowered temperature by numerical simulation

1996

We have numerically investigated the effect of lowered T on the performance of the Coulomb blockade thermometer, which has been demostrated to yield primary thermometry in the high T limit where thermal excitations compete with the Coulomb blockade. The thermometer is formed by an array of tunnel junctions whose differentiated IV—curve is used to determine the temperature. The IV—curves were calculated by computer simulations and we have obtained corrections to the analytic high T behaviour due to the lowered temperature.

Coral growth bands: A new and easy to use paleothermometer in paleoenvironment analysis and paleoceanography (late Miocene, Greece)

2006

[1] Modern scleractinian corals are classical components of marine shallow warm water ecosystems. Their occurrence and diversity patterns in the geological record have been widely used to infer past climates and environmental conditions. Coral skeletal composition data reflecting the nature of the coral environment are often affected by diagenetic alteration. Ghost structures of annual growth rhythms are, however, often well preserved in the transformed skeleton. We show that these relicts represent a valuable source of information on growth conditions of fossil corals. Annual growth bands were measured in massive hemispherical Porites of late Miocene age from the island of Crete (Greece) t…

Compliance with patient-reported outcome assessment in glioma patients: predictors for drop out

2017

Abstract Background Patient-reported outcomes are of high importance in clinical neuro-oncology. However, assessment is still suboptimal. We aimed at exploring factors associated with the probability for a) drop out of study and b) death during follow-up. Methods Patients were assessed twice during follow-up visits scheduled within 3 to 5 months of each other by using 3 validated patient-reported outcome measures (t1: first assessment, t2: second assessment). As “death” was seen as a competing risk for drop out, univariate competing risk Cox regression models were applied to explore factors associated with dropping out (age, gender, WHO grade, living situation, recurrent surgery, Karnofsky …

Temperature sensation: the "3-bowls experiment" revisited.

1990

The "3-bowls experiment", usually attributed to E. H. Weber*, will be remembered by many from their first lab course in human physiology. The left and right hands are immersed for several minutes in bowls containing water at 10 and 40°C, respectively. When both hands are then placed in a third bowl of water at 27 °C, the left hand feels distinctly warm and the right hand distinctly cool. Until now nobody has been able to reconcile this apparent unreliability of the sense of temperature with the observation that humans regularly make judgements of the temperatures of objects; for example, mothers seldom use a thermometer to check the temperature of a baby's milk, but rather hold the bottle a…

Peltier effect-based temperature challenge: an improved method for diagnosing cold urticaria.

2004

Applications of tunnel junctions in low-dimensional nanostructures

2009

This thesis concentrates on studies of AlOx based tunnel junctions and their feasibility for cooling, thermometry and strain sensing in suspended nanostructures. The main result of the thesis is cooling of one dimensional phonon modes of a suspended nanowire with normal metal insulator superconductor (NIS) tunnel junctions. Simultaneous cooling of both electrons and phonons was achieved, and the lowest phonon temperature reached in the system was 42 mK with an initial temperature of 100 mK. In addition, suspended devices show cooling still at a bath temperature of 600 mK. The observed thermal transport characteristics show, that the heat flow is limited by the scattering of phonons at the b…