Authors:Eva Natividad, M. Castro, R. Burriel, and L. Angurel
from 5 to 300 K the thermal conductance of different superconducting Bi-2212
thin rods and one superconducting module integrating a hybrid current lead
based on such rods. The conductance values of the rods are lower than the
measurable limits of the set-up and a detailed evaluation of the heat losses
is required. The analysis of the heat exchanges permits to introduce a correction
function to the measured values and allows to study low thermal conductivity
materials. The dependence of the thermal conductivity of Bi-2212 rods on the
sample microstructure is analyzed after this correction. We calculate analytically
the time required to reach the steady-state for long bars for which extended
relaxation times are expected. From the measured conductance data we estimate
the heat load introduced by the current lead into a cryogenic bath in static
Local plant species richness and composition may vary across habitats and between plant taxonomic groups within temperate deciduous forests. Multi-taxon approach is therefore needed to provide a more detailed insight into determinants affecting vegetation structure. Fifty-four deciduous oak-dominated vegetation plots (20 m × 20 m) were sampled across central Slovakia (Štiavnické vrchy Mts) in order to study the effect of environmental (soil, light, topographic) factors on species richness and composition patterns of two main assemblages of understorey layer (herb-layer vascular plants and ground-dwelling bryophytes). The number of recorded herb-layer vascular plants and ground-dwelling bryophytes was 12–48 (mean 28) and 0–11 (mean 4) species per plot, respectively. Generalized linear model revealed that species richness of herb-layer vascular plants was driven by canopy openness, altitude, soil pH/base saturation gradient and plant-available phosphorus. Canopy openness and heat load index accompanied by soil pH/base saturation gradient determined changes of the ground-dwelling bryophyte richness. Canonical Correspondence Analysis identified soil pH/base saturation gradient, canopy openness, soil silt and topography related predictors (altitude, slope, radiation) as the main drivers of the herb-layer vascular plant compositional variability. Species composition variation of ground-dwelling bryophytes was controlled by radiation and canopy openness.
losses and against summer heatloads. The east and west sides are particularly disadvantageous in office and industrial installations during the summer cooling periods, as the solar load may increase up to 100% relative to a southern orientation
unknown wavelet coefficients, , , denoted the heat capacity matrix of the element, heat exchange matrix of the element, heatload matrix of element, respectively. , , could be expressed as follows [ 16 ]:
13 14 15
The global differential
Authors:Nan Ren, Yu-ting Wu, Tao Wang, and Chong-fang Ma
, liquid metal, with higher using temperate, large density and high heat conductivity, has good performance of endothermic and exothermic, but its heat capacity is small, temperature fluctuate visibly during large heatload and it is easy to combust and
presented as Fourier's equation for unsteady state ( 14 ).
and the expression ( 15 ) is called coefficient of thermal diffusion.
According to Woschni's definition [ 14 , 15 ], heatload in the combustion engine requires qualification of
The formula ( 14 ) and ( 21 ) are inserted into formula ( 20 ), and the following equation is obtained:
where is the heat capacity matrix of curvelet finite element, is the heat exchange matrix of curvelet finite element, is the heatload matrix