scholarly journals Specific Heat and Volumetric Heat Capacity of Some Saudian Soils as affected by Moisture and Density

2020 ◽  
Vol 7 ◽  
Keyword(s):  
Heat Capacity ◽  
Moisture Content ◽  
Specific Heat ◽  
Laboratory Experiments ◽  
Soil Density ◽  
Volumetric Heat Capacity ◽  
Moisture Contents ◽  
Soil Temperature Regime ◽  
Loam Soil ◽  
Soil Heat Capacity

The ability to monitor soil heat capacity is an important mean in managing the soil temperature regime, which in turn, affects its ability to store heat. The effect of water content and bulk density on the specific heat and volumetric heat capacity of two Saudian soils (sand and loam) was investigated through laboratory studies. These laboratory experiments used the calorimetric method to determine specific heat of soils. For the type of soils studied, specific heat increased with increased moisture content. Also, volumetric heat capacity increased with increased moisture content and soil density. Volumetric heat capacity ranged from 1.55 to 3.50 for loam and from 1.06 to 3.00 MJ/m3 / o C for sand at moisture contents from 0 to 0.20 (kg/kg) and densities from 1200 to 1400 kg/m3 . Specific heat ranged from 1140 to 2090 for loam and from 800 to 1530 J/kg/ oC for sand at moisture contents from 0.01 to 0.20 (kg/kg) and soil density of 1200 kg/m3 . The volumetric heat capacity and specific heat of soils observed in this study under varying moisture content and soil density were compared with independent estimates made using derived theoretical relations. The differences between the observed and predicted results were very small. Loam soil generally had higher specific heat and volumetric heat capacity than sandy soil for the same moisture content and soil density.

Specific Heat and Volumetric Heat Capacity of Granular Materials as Affected by Moisture and Density

2014 ◽  
Vol 575 ◽  
pp. 103-107 ◽  
Author(s):  
Nidal H. Abu-Hamdeh
Keyword(s):  
Heat Capacity ◽  
Moisture Content ◽  
Specific Heat ◽  
Granular Materials ◽  
Sandy Soil ◽  
Laboratory Experiments ◽  
Soil Density ◽  
Laboratory Studies ◽  
Volumetric Heat Capacity ◽  
Loam Soil

The granular materials examined in this study were some Saudian soils. The effect of water content and bulk density on the specific heat and volumetric heat capacity of two Saudian soils (sand and loam) was investigated through laboratory studies. These laboratory experiments used the calorimetric method to determine specific heat of soils. For the type of soils studied, specific heat increased with increased moisture content. Also, volumetric heat capacity increased with increased moisture content and soil density. The volumetric heat capacity and specific heat of soils observed were compared with independent estimates made using derived theoretical relations. The differences between the observed and predicted results were very small. Loam soil generally had higher specific heat and volumetric heat capacity than sandy soil for the same moisture content and soil density.

scholarly journals Draft Requirement of Two Animal - Drawn Institute for Agricultural Research (IAR) Weeders

2020 ◽  
pp. 14-20
Author(s):  
Y. A. Unguwanrimi ◽  
A. M. Sada ◽  
G. N. Ugama ◽  
H. S. Garuba ◽  
A. Ugoani
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Bulk Density ◽  
Soil Moisture Content ◽  
Agricultural Research ◽  
Soil Samples ◽  
Soil Conditions ◽  
Experimental Plot ◽  
Moisture Contents ◽  
Loam Soil

Draft requirements of two animal – drawn (IAR) weeders operating on loam soil were determined in the study. The implements include a straddle row weeder and an emcot attached rotary weeder evaluated under the same soil conditions, using a pair of white Fulani breed of oxen. The animal draft requirement was first estimated from the animal ergonomics measurements. Using area of 0.054 hectare as experimental plot for each implement the draft requirement of each implement was investigated after taking soil samples for soil moisture content and bulk density determinations. The implements tested showed variation in their average draft requirement. The straddle row weeder had the highest value of 338.15 N respectively while the emcot attached rotary weeder had the lowest value of 188.12 N with 47.03%, respectively. The average soil moisture contents and bulk density were 13.0% and 1.46%/cm3, respectively.

Effect of timeliness on the thermal properties of paraffin-based Al2O3 nanofluids

2019 ◽  
Vol 33 (05) ◽  
pp. 1950051
Author(s):  
Yangyang Wu ◽  
Baichao Wang ◽  
Dong Li ◽  
Changyu Liu
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Volume Concentration ◽  
Volume Fraction ◽  
Thermal Conversion ◽  
Volumetric Heat Capacity ◽  
Energy Storage Material ◽  
Over Time

Paraffin is an excellent photo-thermal conversion phase change energy storage material, and extensively used in the thermal storage field at the medium-low temperature. However, the low thermal conductivity of paraffin restricts its application in practice. Adding nanoparticles into paraffin is one of the effective methods to improve its thermal conductivity. Nevertheless, the thermal diffusivity, specific heat and volumetric heat capacity of paraffin as well as timeliness were affected after the addition of nanoparticles. In this paper, the influences of volume fraction of Al2O3 nanoparticle and timeliness on these thermal parameters of paraffin were investigated. The results show that the thermal conductivity of paraffin-based Al2O3 nanofluids increases first and then decreases with time, and the maximum thermal conductivity is 0.34 W/[Formula: see text] for volume fraction 1% on third day. The higher volume concentration, the lower specific heat and volumetric heat capacity, all present downtrend over time, until stable in the range of 0.3 MJ/[Formula: see text] and 0.4 MJ/[Formula: see text]. The average enhancement rate of specific heat and volumetric heat capacity are concentrates on −6% to 9%, −10% to 0%, respectively. While increasing the volume concentration, the thermal diffusivity has no obvious regularity, and presents undulatory property over time.

Thermal Properties of Selected Timbers

2014 ◽  
Vol 982 ◽  
pp. 100-103 ◽  
Author(s):  
Dana Koňáková ◽  
Monika Čáchová ◽  
Eva Vejmelková ◽  
Martin Keppert ◽  
Robert Černý
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Moisture Content ◽  
Specific Heat ◽  
Heat Transport ◽  
Specific Heat Capacity ◽  
Open Porosity ◽  
Building Structures ◽  
The Difference

This article deals with thermal properties of selected kinds of timber. Wood, generally, is one of often used natural materials in building structures. For our research, woods were selected according to frequency of utilization in civil engineering branch. Four different timbers were chosen, and experimental determinations of their properties were performed. Basic physical properties as well as thermal properties belong among studied characteristics. From achieved results, it is obvious, that the bulk density of studied wood ranges between 373 kg m-3 and 649 kg m-3, the open porosity differ by 13%. Regarding thermal properties, values of the thermal conductivity as well as the specific heat capacity are influenced mainly by the open porosity and moisture content. The thermal conductivity in dry state varies by about 31% while in the case of the specific heat capacity the difference is about 19%. Obtained date will be used in the mathematical analysis of heat transport in building structures.

Effects of Engineering Properties on the Poppability of Nigerian Popcorn

2009 ◽  
Vol 5 (1) ◽  
Author(s):  
Taiwo Falilat Ademiluyi ◽  
Horsfall Doopue Mepba
Keyword(s):  
Heat Capacity ◽  
Specific Heat ◽  
Engineering Properties ◽  
Medium Size ◽  
Salt Treatment ◽  
Kernel Size ◽  
Local Varieties ◽  
Overall Acceptability ◽  
Moisture Contents ◽  
Deep Yellow

The effects of some engineering properties on the poppability of three Nigerian popcorn hybrids were investigated. Properties such as moisture, porosity, bulk density, kernel size and ingredient used in popping were found to affect the popping volume of Nigerian popcorn. Popped ratio and popping volume increased with increasing moisture contents and reaching a peak at 14.0% moisture, then declined progressively. Sugar treatments increased popping volume while salt treatment increased popped ratio. Kernel bulk densities ranged from 730 – 860 kg/m3 and declined linearly with increased moisture contents. Local hybrids (4.43 – 5.75 mm in diameter) had specific heat capacity, porosity and popping time ranging from 1.84 ± 0.2 – 1.87 ± 0.2 kJ/kg K, 38.8 ± 0.2 – 42.9 ± 0.2% and 110 ± 0.1 – 129.0 ± 0.1 seconds, respectively. Smaller size kernels had the highest popped ratios while medium size kernels had the highest popping volume. The Nigerian popcorn hybrids were rich in carbohydrate (60.7 ± 0.3 – 64.0 ± 0.4%), protein (8.3 ± 0.3 – 8.7 ± 0.2%), fat (6.6 ± 0.2 – 8.8 ± 0.2%) and crude fiber (2.9 ± 0.2 – 3.9 ± 0.1%). The deep yellow Nigerian popcorn hybrid was rated significantly (P ? 0.05) higher than all the local varieties and foreign type for crispiness, taste, mealiness, flavour/aroma, and overall acceptability characteristics. Generally, Nigerian popcorn hybrid compared favourably with the foreign type for colour and overall acceptability characteristics but were rated significantly (P ? 0.05) higher for crispness.

scholarly journals Effect of Grouser Height on the Tractive Performance of Single Grouser Shoe under Different Soil Moisture Contents in Clay Loam Terrain

2021 ◽  
Vol 13 (3) ◽  
pp. 1156
Author(s):  
Sher Ali Shaikh ◽  
Yaoming Li ◽  
Ma Zheng ◽  
Farman Ali Chandio ◽  
Fiaz Ahmad ◽  
...  
Keyword(s):  
Moisture Content ◽  
Displacement Sensor ◽  
Soil Conditions ◽  
Clay Loam ◽  
Single Track ◽  
Moisture Contents ◽  
Ac Motor ◽  
Maximum Decrease ◽  
Loam Soil ◽  
Soil Bin

The grouser height and soil conditions have a considerable influence on the tractive performance of single-track shoe. A soil bin-based research was conducted to assess the influence of grouser height on the tractive performance of single-track shoe at different moisture contents of clay loam soil. Eight moisture contents (7.5, 12, 16.7, 21.5, 26.2, 30.7, 35.8, and 38%) and three grouser heights (45, 55, and 60 mm) were comprised during this study. The tractive performance parameters of (thrust, running resistance, and traction) were determined by penetration test. A sensor-based soil bin was designed for penetration tests, which was included penetration system (AC motor, loadcell, and displacement sensor). The test results revealed that soil cohesion was decreased, and adhesion was increased after 16.7% moisture content. Soil thrust at lateral sides and bottom of grouser were increased before 16.7%, and then decreased for all the three heights but the major decrease was observed at 45 mm height. The motion resistance was linearly decreased, the more reduction was on 45 mm at 38% moisture content. The traction of the single-track shoe was decreased with a rise in moisture content, the maximum decrease was on 45 mm grouser height at 38% moisture content. It could be concluded that an off-road tracked vehicle (crawler combine harvester) with 45 mm grouser height of single-track shoe could be operated towards a moderate moisture content range (16.7–21.5%) under paddy soil for better traction.

THE EFFECTS OF BARK MOISTURE ON POLYGRAPHUS RUFIPENNIS (COLEOPTERA: SCOLYTIDAE) ADULTS AND THEIR DEVELOPING BROODS

1967 ◽  
Vol 99 (6) ◽  
pp. 561-564 ◽  
Author(s):  
G. E. Beanlands
Keyword(s):  
Adverse Effects ◽  
Moisture Content ◽  
Laboratory Experiments ◽  
Immature Stages ◽  
Rate Of Development ◽  
Factors Associated ◽  
Moisture Contents ◽  
Spruce Bark ◽  
Survival And Development ◽  
Brood Success

AbstractLaboratory experiments were conducted to determine the effects of bark moisture content on the survival and development of Polygraphus rufipennis (Kirby). Adults and immature stages were reared in white spruce bark of five different moisture contents for 20, 40, and 60 days. Adult activity and brood success were related to the moisture content of the bark with the adverse effects of the drier bark becoming more pronounced with time. After 40 days factors associated with high bark moisture levels, such as fungus and rate of decomposition, may have been responsible for a decrease in survival and rate of development in the moister bark.

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