Temperature-insensitive silicone composites as ballistic witness materials: the impact of water content on the thermophysical properties

2021 ◽  
Author(s):  
Ran Tao ◽  
Fan Zhang ◽  
Huong Giang Nguyen ◽  
Philip Bernstein ◽  
Amanda L. Forster ◽  
...  
Keyword(s):  
Water Content ◽  
Thermophysical Properties ◽  
The Impact

scholarly journals Numerical Simulation of Non-Homogeneous Viscous Debris-Flows Based on the Smoothed Particle Hydrodynamics (SPH) Method

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2314 ◽  
Author(s):  
Shu Wang ◽  
Anping Shu ◽  
Matteo Rubinato ◽  
Mengyao Wang ◽  
Jiping Qin
Keyword(s):  
Debris Flow ◽  
Water Content ◽  
Smoothed Particle Hydrodynamics ◽  
Debris Flows ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Sph Model ◽  
Smoothed Particle ◽  
The Impact ◽  
Kinetic And Potential Energies

Non-homogeneous viscous debris flows are characterized by high density, impact force and destructiveness, and the complexity of the materials they are made of. This has always made these flows challenging to simulate numerically, and to reproduce experimentally debris flow processes. In this study, the formation-movement process of non-homogeneous debris flow under three different soil configurations was simulated numerically by modifying the formulation of collision, friction, and yield stresses for the existing Smoothed Particle Hydrodynamics (SPH) method. The results obtained by applying this modification to the SPH model clearly demonstrated that the configuration where fine and coarse particles are fully mixed, with no specific layering, produces more fluctuations and instability of the debris flow. The kinetic and potential energies of the fluctuating particles calculated for each scenario have been shown to be affected by the water content by focusing on small local areas. Therefore, this study provides a better understanding and new insights regarding intermittent debris flows, and explains the impact of the water content on their formation and movement processes.

The Experiment on Soil Water Characteristic Curve Considering the Effect of Urea Concentration

2014 ◽  
Vol 919-921 ◽  
pp. 795-799
Author(s):  
Gai Qing Dai ◽  
Dong Fang Tian ◽  
Yao Ruan ◽  
Lang Tian ◽  
You Le Wang
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Characteristic Curve ◽  
Urea Concentration ◽  
Test Method ◽  
Materials Selection ◽  
Valuable Data ◽  
Soil Water Characteristic Curve ◽  
Concentration Test ◽  
The Impact

A new soil water characteristic curve (SWCC) experiment contemplating urea concentration is presented in the paper. We focus on the impact of the SWCC considering urea concentration test method for materials selection and introduction, experimental results, and finally, we have conducted some experiments of SWCC and obtained some valuable data which could affect urea concentration. By using linear fitting, an exponential function between water content and suction and urea concentration is established.

Dependence of efficiency of natural fish reproduction in water bodies of Kazakhstan from water level

2021 ◽  
pp. 32-41
Author(s):  
K.B. Isbekov ◽  
E.V. Kulikov ◽  
S.Zh. Asylbekova
Keyword(s):  
Water Content ◽  
Water Regime ◽  
Juvenile Fish ◽  
Hydrological Regime ◽  
Water Bodies ◽  
Fish Reproduction ◽  
Data Set ◽  
Commercial Fish ◽  
Level Of Significance ◽  
The Impact

The article deals with the relationship between the hydrological regime of water bodies and the efficiency of fish reproduction. The hydrological regime of water bodies in years of different water content influences the reproduction and, accordingly, the quantitative and qualitative composition of ichthyocenoses. The easiest way to assess the efficiency of fish reproduction is by such an indicator as the productivity of juveniles, i.e. the number of juvenile fish per unit area or volume. The material for this work was carried out in large fishing reservoirs of the Republic of Kazakhstan in the process of fishery research (2013–2018). Comparison of hydrological parameters and productivity of juveniles by years shows their relationship. Correlation coefficient between water content (runoff) of the river Zhaiyk and juvenile yield +0.73 (data set for 11 years, reliable for the level of significance p = 0.01). The yield of juvenile fish from Lake Balkhash has a high correlative dependence on the inflow of water into the lake (r = +0.826) (massif 2013–2018, reliable for the level of significance p = 0.05). Correlation analysis showed that the productivity of juvenile fish in the Kapshagai reservoir has an average degree of dependence on water content (average annual level) (r = +0.641, reliable for the level of significance p = 0.05). Regular relationships between the water regime and the efficiency of reproduction (productivity of juveniles) of fish have been established. The efficiency of natural reproduction of commercial fish species in modern conditions of the water regime, water withdrawal for economic needs and the impact of fishing is significantly reduced, but with the implementation of the reclamation measures proposed in the work, its partial restoration is possible.

The impact of cloud inhomogeneities on the Earth radiation budget: the 14 October 1989 I.C.E. convective cloud case study

1994 ◽  
Vol 12 (2/3) ◽  
pp. 240-253 ◽  
Author(s):  
F. Parol ◽  
J. C. Buriez ◽  
D. Crétel ◽  
Y. Fouquart
Keyword(s):  
Aspect Ratio ◽  
Water Content ◽  
Liquid Water ◽  
Convective Cloud ◽  
Liquid Water Content ◽  
Radiation Budget ◽  
The Earth ◽  
Earth Radiation Budget ◽  
The Impact ◽  
Earth Radiation

Abstract. Through their multiple interactions with radiation, clouds have an important impact on the climate. Nonetheless, the simulation of clouds in climate models is still coarse. The present evolution of modeling tends to a more realistic representation of the liquid water content; thus the problem of its subgrid scale distribution is crucial. For a convective cloud field observed during ICE 89, Landsat TM data (resolution: 30m) have been analyzed in order to quantify the respective influences of both the horizontal distribution of liquid water content and cloud shape on the Earth radiation budget. The cloud field was found to be rather well-represented by a stochastic distribution of hemi-ellipsoidal clouds whose horizontal aspect ratio is close to 2 and whose vertical aspect ratio decreases as the cloud cell area increases. For that particular cloud field, neglecting the influence of the cloud shape leads to an over-estimate of the outgoing longwave flux; in the shortwave, it leads to an over-estimate of the reflected flux for high solar elevations but strongly depends on cloud cell orientations for low elevations. On the other hand, neglecting the influence of cloud size distribution leads to systematic over-estimate of their impact on the shortwave radiation whereas the effect is close to zero in the thermal range. The overall effect of the heterogeneities is estimated to be of the order of 10 W m-2 for the conditions of that Landsat picture (solar zenith angle 65°, cloud cover 70%); it might reach 40 W m-2 for an overhead sun and overcast cloud conditions.

scholarly journals Utilization of Electroplating Sludge as Subgrade Backfill Materials: Mechanical and Environmental Risk Evaluation

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Yu Zhang ◽  
Peixin Shi ◽  
Lijuan Chen ◽  
Qiang Tang
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Water Content ◽  
Environmental Risk ◽  
Coal Fly Ash ◽  
Surrounding Environment ◽  
Electroplating Sludge ◽  
Backfill Materials ◽  
Standard Limit ◽  
The Impact

The electroplating sludge may pose serious threat to human health and surrounding environment without safe treatment. This paper investigated the feasibility of using electroplating sludge as subgrade backfill materials, by evaluating the mechanical properties and environmental risk of the cement-coal fly ash solidified sludge. In this study, Portland cement and coal fly ash are used to solidify/stabilize the sludge. After curing for 7, 14, and 28 days, the stabilization/solidification sludge specimens were subject to a series of mechanical, leaching, and microcosmic tests. It was found that the compressive strength increased with the increase of cement content, curing time, and the cement replacement by coal fly ash besides water content. Among these factors, the impact of water content on the compressive strength is most noticeable. It was observed that the compressive strength declined by 87.1% when the water content increased from 0% to 10%. Besides, leaching tests showed that the amount of leaching heavy metals were under the standard limit. These results demonstrated utilization of electroplating sludge in subgrade backfill material may provide an alternative for the treatment of electroplating sludge.

scholarly journals An empirical model for describing the influence of water content and concentration of sulfamethoxazole (antibiotic) in soil on the total net CO2 efflux

2020 ◽  
Vol 68 (4) ◽  
pp. 351-358
Author(s):  
Miroslav Fér ◽  
Radka Kodešová ◽  
Barbora Kalkušová ◽  
Aleš Klement ◽  
Antonín Nikodem
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Solution Treatment ◽  
Soil Microbial Activity ◽  
Soil Samples ◽  
Co2 Efflux ◽  
The Impact ◽  
Water Contents ◽  
Soil Water Contents

AbstractThe aim of the study was to describe the impact of the soil water content and sulfamethoxazole, SUL, (antibiotic) concentration in soil on the net CO2 efflux. Soil samples were taken from topsoils of a Haplic Fluvisol and Haplic Chernozem. Soil samples were packed into the steel cylinders. The net CO2 efflux was measured from these soil columns after application of fresh water or SUL solution at different soil water contents. The experiments were carried out in dark at 20°C. The trends in the net CO2 efflux varied for different treatments. While initially high values for water treatment exponentially decreased in time, values for solution treatment increased during the first 250–650 minutes and then decreased. The total net CO2 effluxes measured for 20 hours related to the soil water content followed the second order polynomial functions. The maximal values were measured for the soil water content of 0.15 cm3 cm−3 (Haplic Fluvisol with water or solution, Haplic Chernozem with solution) and 0.11 cm3 cm−3 (Haplic Chernozem with water). The ratios between values measured for solution and water at the same soil water contents exponentially increased with increasing SUL concentration in soils. This proved the increasing stimulative influence of SUL on soil microbial activity.

scholarly journals Factors determining the soil available water during the last two decades (1997–2019) in southern Spain

2021 ◽  
Vol 14 (19) ◽  
Author(s):  
José A. Sillero-Medina ◽  
Jesús Rodrigo-Comino ◽  
José D. Ruiz-Sinoga
Keyword(s):  
Climate Change ◽  
Water Content ◽  
Southern Spain ◽  
Retention Capacity ◽  
Essential Information ◽  
Hydrological Conditions ◽  
Available Water ◽  
Available Water Content ◽  
The Mediterranean ◽  
The Impact

AbstractAssessing soil hydrological conditions can provide essential information for understanding the environmental processes that affect ecosystem services and, particularly in the context of ongoing climate change. This is key in areas affected by water scarcity such as the Mediterranean belt. Therefore, the main goals of this research are (i) to assess the main rainfall dynamics and trends of some representative hotspots along with southern Spain and (ii) to determine the impact on the soil available water content (AWC) over the last two decades. An analysis of daily precipitation and soil hydrological conditions was combined with soil sampling (543) and laboratory analyses to evaluate the properties related to the soil infiltration and retention capacity. The results show that the organic factors control soil properties and their hydrodynamics in southern Spain. Furthermore, a general declining trend in soil water availability is observed over the last two decades. This is more extreme in arid and semi-arid areas, where there have been several years in the last decade with more than 200 days without the available water content. Moreover, in these areas, heavy rainfall during specific moments of the year is the key factor that manifests a greater incidence in areas with steeper slopes, which in turn, also conditions the biological factors and the hydrodynamics of the soil. In short, in the context of climate change, the analysis of soil hydrological dynamics could be used to identify biodiversity thresholds in the Mediterranean area and even to detect phenological changes in specific plant species.

scholarly journals Applications of nanotechnology with hybrid Photovoltaic/Thermal systems

2020 ◽  
pp. 1-15
Author(s):  
Mohammed Alktranee
Keyword(s):  
Thermophysical Properties ◽  
Base Fluid ◽  
Volume Fraction ◽  
Working Fluid ◽  
Spectral Filter ◽  
Thermal Systems ◽  
Cooling Fluid ◽  
Numerical Studies ◽  
The Impact ◽  
T System

This paper appears potential of use nanofluids as a working fluid with the photovoltaic/thermal (PV/T) systems as an alternative of the conventional liquids in improves the efficiency of the hybrid PV/T system. The review highlights the impact of some parameters (base fluid, volume fraction, the concentration of nanoparticles, surfactants, shape, and size of nanoparticles) on nanofluids' thermophysical properties and their effect on the PV/T system's efficiencies. Hence, it discusses the PV/T behavior, which uses different nanofluids based on previous experimental, analytical, and numerical studies. The review concluded that using nanofluid as a cooling fluid or spectral filter contributes by enhancing the performance and increasing the PV/T system's efficiency. Thus, each type of nanofluids has certain features that contribute to removing the PV cells' excess heat by cooling it, contributing to its work's stability, and increasing its productivity. Nanofluids thermophysical properties play an intrinsic role by enhancing nanofluids' performance, thus positively reflecting on the PV/T system's performance. Despite the variation in the values of thermal and electrical efficiency, Most of the studies that used nanofluids have achieved encouraging results that appeared by improving the performance of PV/T systems.

scholarly journals Numerical Study of Heat and Mass Transfer during the Thermal Drying of Tropical Woods

2014 ◽  
Vol 08 (1) ◽  
Keyword(s):  
Water Content ◽  
Thermophysical Properties ◽  
Numerical Study ◽  
Wood Quality ◽  
Central Africa ◽  
Industrial Process ◽  
Self Control ◽  
Heat Equations ◽  
Wood Drying ◽  
Tropical Woods

A sector of utilization and transformation of wood give much money at the countries of the central Africa region. If we want to increase these advantages, it is important to do locally the first and second transformations of wood. Self-control of the wood drying is necessary to ameliorate a wood quality and to preserve an art work doing in wood. In this article, we are modeling a drying of one piece of bete wood (Mansonia altissima) with dimensions are 1m of length and thickness is no more than 25cm. We have used a literature to obtain a mass and heat equations and the thermophysical properties of the present wood. We have considered some thermophysical properties that we are unkempt in the precedent work [1]. We have experimentally obtained a relationship between a density of this wood with a water content. The others thermophysical properties come from the literature [1,2]. We have simulated a wood drying in the constant conditions and in the conditions of the bete drying table established by CIRAD Organization. A sensibility study is doing to validate a modeling. Then, the present modeling explains temperature, mass fraction of the vapor in air and water content evolutions during the industrial process of drying. This modeling can to be used for to overhaul a drying table of bete wood and the others of tropical woods. This work uses a gaseous pressure can be used to explain the drying with the high temperatures conditions.

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