scholarly journals The new method of determining the soil thermal diffusivity by using a simple apparatus.

1989 ◽  
Vol 27 (1) ◽  
pp. 15-21
Author(s):  
Minoru ITO ◽  
Yulin YI
Keyword(s):  
Thermal Diffusivity ◽  
New Method ◽  
Simple Apparatus ◽  
Soil Thermal Diffusivity

Non-invasive Measurements of Oilseed Temperature in Soil and Soil Thermal Diffusivity Using Time-Domain NMR Relaxometry

2018 ◽  
Vol 49 (10) ◽  
pp. 1119-1127
Author(s):  
Maria G. A. Carosio ◽  
Diego F. Bernardes ◽  
André de S. Carvalho ◽  
Luiz A. Colnago
Keyword(s):  
Thermal Diffusivity ◽  
Time Domain ◽  
Non Invasive ◽  
Nmr Relaxometry ◽  
Soil Thermal Diffusivity

scholarly journals An Empirical Model for Estimating Soil Thermal Diffusivity from Texture, Bulk Density, and Degree of Saturation

2018 ◽  
Vol 19 (2) ◽  
pp. 445-457 ◽  
Author(s):  
Xiaoting Xie ◽  
Yili Lu ◽  
Tusheng Ren ◽  
Robert Horton
Keyword(s):  
Thermal Diffusivity ◽  
Bulk Density ◽  
Empirical Model ◽  
Soil Texture ◽  
Degree Of Saturation ◽  
Model Parameters ◽  
Near Surface ◽  
New Model ◽  
Soil Thermal Diffusivity ◽  
Mean Square Errors

Abstract Soil thermal diffusivity κ is an essential parameter for studying surface and subsurface heat transfer and temperature changes. It is well understood that κ mainly varies with soil texture, water content θ, and bulk density ρb, but few models are available to accurately quantify the relationship. In this study, an empirical model is developed for estimating κ from soil particle size distribution, ρb, and degree of water saturation Sr. The model parameters are determined by fitting the proposed equations to heat-pulse κ data for eight soils covering wide ranges of texture, ρb, and Sr. Independent evaluations with published κ data show that the new model describes the κ(Sr) relationship accurately, with root-mean-square errors less than 0.75 × 10−7 m2 s−1. The proposed κ(Sr) model also describes the responses of κ to ρb changes accurately in both laboratory and field conditions. The new model is also used successfully for predicting near-surface soil temperature dynamics using the harmonic method. The results suggest that this model provides useful estimates of κ from Sr, ρb, and soil texture.

New method for the study of mirror heating of a semiconductor laser diode and for the determination of thermal diffusivity of the entire structure

1994 ◽  
Vol 65 (18) ◽  
pp. 2266-2268 ◽  
Author(s):  
M. Bertolotti ◽  
G. L. Liakhou ◽  
R. Li Voti ◽  
C. Sibilia ◽  
A. Syrbu ◽  
...  
Keyword(s):  
Thermal Diffusivity ◽  
Semiconductor Laser ◽  
Laser Diode ◽  
New Method ◽  
Semiconductor Laser Diode ◽  
Entire Structure

scholarly journals Estimation of depth-resolved profiles of soil thermal diffusivity from temperature time series and uncertainty quantification

2021 ◽  
Author(s):  
Carlotta Brunetti ◽  
John Lamb ◽  
Stijn Wielandt ◽  
Sebastian Uhlemann ◽  
Ian Shirley ◽  
...  
Keyword(s):  
Time Series ◽  
Thermal Diffusivity ◽  
Physical Properties ◽  
Environmental Conditions ◽  
Temperature Sensor ◽  
Time Window ◽  
Temperature Time Series ◽  
Soil Thermal Diffusivity ◽  
Temperature Time ◽  
Over Time

Abstract. Improving the quantification of soil thermal and physical properties is key to achieving a better understanding and prediction of soil hydro-biogeochemical processes and their responses to changes in atmospheric forcing. Obtaining such information at numerous locations and/or over time with conventional soil sampling is challenging. The increasing availability of low-cost, vertically resolved temperature sensor arrays offers promise for improving the estimation of soil thermal properties from temperature time series, and the possible indirect estimation of physical properties. Still, the reliability and limitations of such an approach needs to be assessed. In the present study, we develop a parameter estimation approach based on a combination of thermal modeling, sliding time-windows, Bayesian inference, and Markov chain Monte Carlo simulation to estimate thermal diffusivity and its uncertainty over time, at numerous locations and at an unprecedented vertical spatial resolution (i.e., down to 5 to 10 cm vertical resolution) from soil temperature time series. We provide the necessary framework to assess under which environmental conditions (soil temperature gradient, fluctuations, and trend), temperature sensor characteristics (bias and level of noise) and deployment geometries (sensor number and position) soil thermal diffusivity can be reliably inferred. We validate the method with synthetic experiments and field studies. The synthetic experiments show that in the presence of median diurnal fluctuations ≥ 1.5 °C at 5 cm below the ground surface, temperature gradients > 2 °C m−1, and a sliding time-window of at least 4 days, the proposed method provides reliable depth-resolved thermal diffusivity estimates with percentage errors ≤ 10 % and posterior relative standard deviations ≤ 5 % up to 1 m depth. Reliable thermal diffusivity under such environmental conditions also requires temperature sensors spaced precisely (with few-millimeter accuracy), with a level of noise ≤ 0.02 °C, and with a bias defined by a standard deviation ≤ 0.01 °C. Finally, the application of the developed approach to field data indicates significant repeatability in results and similarity with independent measurements, as well as promise in using a sliding time-window to estimate temporal changes in soil thermal diffusivity, as needed to potentially capture changes in carbon or water content.

Apolipoprotein E phenotype determined by agarose gel electrofocusing and immunoblotting.

1989 ◽  
Vol 35 (10) ◽  
pp. 2070-2073 ◽  
Author(s):  
I F McDowell ◽  
G B Wisdom ◽  
E R Trimble
Keyword(s):  
Monoclonal Antibody ◽  
Apolipoprotein E ◽  
New Method ◽  
Agarose Gel ◽  
Simple Apparatus ◽  
Type Iii ◽  
Large Numbers ◽  
Apoe Locus ◽  
Peroxidase Conjugate

Abstract Polymorphism at the apolipoprotein E (ApoE) locus is an important factor in the development of remnant (Type III) hyperlipidemia and also influences the distribution of cholesterol concentrations in the population. The new method for ApoE phenotyping described here gives good results with simple apparatus. Serum (10 microL) is digested with sialidase (EC 3.2.1.18), delipidated, and redissolved in 6 mol/L urea. Electrofocusing is carried out in agarose, followed by immunoblotting with a monoclonal antibody to ApoE and an anti-immunoglobulin-peroxidase conjugate. Sialidase-catalyzed digestion effectively removes sialated forms of ApoE, which eases interpretation. This method can be used in nonspecialist laboratories and is particularly suited for assay of large numbers of samples.

Sign in / Sign up

Export Citation Format

Share Document