Search results for "TEMPERATURES"
showing 10 items of 70 documents
Measuring basal soil respiration across Europe: Do incubation temperature and incubation period matter?
2014
The European Commission recognises the essential role of soil biology in soil functioning and delivery of ecosystem services, but information is currently lacking evaluate of how these vary across soil and land-use types at a European scale. This study evaluated the measurement of the initial rate of soil basal respiration (BR) as a potential biological indicator of ecosystem service provision. The purpose of this study was to test ISO 16072:2002 (Soil Quality: Laboratory methods for the determining of microbial soil respiration). In the literature a range of pre-incubation temperatures (pre-inc) and experimental incubation temperatures (exp-inc) have been applied when using the ISO method …
Global, regional, and national burden of mortality associated with non-optimal ambient temperatures from 2000 to 2019: a three-stage modelling study
2021
Background: Exposure to cold or hot temperatures is associated with premature deaths. We aimed to evaluate the global, regional, and national mortality burden associated with non-optimal ambient temperatures. Methods: In this modelling study, we collected time-series data on mortality and ambient temperatures from 750 locations in 43 countries and five meta-predictors at a grid size of 0·5° × 0·5° across the globe. A three-stage analysis strategy was used. First, the temperature–mortality association was fitted for each location by use of a time-series regression. Second, a multivariate meta-regression model was built between location-specific estimates and meta-predictors. Finally, the gri…
Comparison of the effect of non-polluted and underwater-volcano-polluted seawater on the corrosion resistance of different stainless steels
2015
This work compares the effect of non‐polluted and underwater‐volcano‐polluted seawater on the electrochemical behavior of two different alloys, notably an austenitic stainless steel (SS) and a duplex stainless steel. Polarization measurements, potentiostatic passivation tests, electrochemical impedance spectroscopy and capacitance measurements were performed. Results show that the composition of the polluted seawater negatively affects the passivation kinetics of both AISI 316 SS and Alloy 900, decreasing the corrosion resistance of both alloys. Additionally, when both steels are compared, it can be concluded that passive films formed on Alloy 900 presented better protective properties than…
Intervalley-scattering-induced electron-phonon energy relaxation in many-valley semiconductors at low temperatures
2005
We report on the effect of elastic intervalley scattering on the energy transport between electrons and phonons in many-valley semiconductors. We derive a general expression for the electron-phonon energy flow rate at the limit where elastic intervalley scattering dominates over diffusion. Electron heating experiments on heavily doped n-type Si samples with electron concentration in the range $3.5-16.0\times 10^{25}$ m$^{-3}$ are performed at sub-1 K temperatures. We find a good agreement between the theory and the experiment.
Fractional-order theory of heat transport in rigid bodies
2014
Abstract The non-local model of heat transfer, used to describe the deviations of the temperature field from the well-known prediction of Fourier/Cattaneo models experienced in complex media, is framed in the context of fractional-order calculus. It has been assumed (Borino et al., 2011 [53] , Mongiovi and Zingales, 2013 [54] ) that thermal energy transport is due to two phenomena: ( i ) A short-range heat flux ruled by a local transport equation; ( ii ) A long-range thermal energy transfer proportional to a distance-decaying function, to the relative temperature and to the product of the interacting masses. The distance-decaying function is assumed in the functional class of the power-law …
Interspecific hybridisation among diverse Saccharomyces species: A combined biotechnological solution for low-temperature and nitrogen-limited wine f…
2019
Lack of the prezygotic barrier in the Saccharomyces genus facilitates the construction of artificial interspecific hybrids among different Saccharomyces species. Hybrids that maintain the interesting features of parental strains have been applied in industry for many beneficial purposes. Two of the most important problems faced by wine makers is nitrogen deficiency in grape must and low-temperature fermentation. In our study, hybrids were constructed by using selected low nitrogen-demanding cryotolerant S. eubayanus, S. uvarum strains and S. cerevisiae. The fermentation capacity of the hybrid strains was tested under four conditions by combining two temperatures, 12 °C and 28 °C, and two ni…
Ascorbic Acid Oxidation in Sucrose Aqueous Model Systems at Subzero Temperatures
2004
The reduction of Tempol by ascorbic acid in concentrated sucrose solutions was measured by electron paramagnetic resonance (EPR) at temperatures ranging from 16 to −16 °C. This method allowed the determination of the rate constants (k) of this fast reaction, by recording the Tempol reduction as a function of time. The two reactants were initially separated and had to migrate for the reaction to occur. The experimental findings were compared with predicted values according to the equation for diffusion-controlled reaction proposed by Atkins. The experimental reaction rate constants were observed to be lower than the calculated ones. However, the experimental values were found to be controlle…
Disordered hyperuniformity in superconducting vortex lattices
2020
Particles occupying sites of a random lattice present density fluctuations at all length scales. It has been proposed that increasing interparticle interactions reduces long range density fluctuations, deviating from random behaviour. This leads to power laws in the structure factor and the number variance that can be used to characterize deviations from randomness which eventually lead to disordered hyperuniformity. It is not yet fully clear how to link density fluctuations with interactions in a disordered hyperuniform system. Interactions between superconducting vortices are very sensitive to vortex pinning, to the crystal structure of the superconductor and to the value of the magnetic …
Cooperative Thermal and Optical Switching of Spin States in a New Two-Dimensional Coordination Polymer
2003
{Fe(pmd)2[Cu(CN)2]2} (pmd = pyrimidine) displays a rigid two-dimensional structure and undergoes thermal- and optical-driven spin crossover behaviour; cooperative elastic coupling between iron(II) ions in the framework induces thermal hysteresis in the HS↔LS conversion and sigmoidal HS→LS relaxation of the photo-induced HS state at low temperatures. Niel, Virginie, Virginie.Niel@uv.es ; Galet Domingo, Ana Guadalupe, Ana.Galet@uv.es ; Gaspar Pedros, Ana Belen, Ana.B.Gaspar@uv.es ; Real Cabezos, Jose Antonio, Jose.A.Real@uv.es
Zooplankton dynamics during autumn circulation in a small, wind-sheltered, Mediterranean lake
2006
12 pages, and tables statistics.