Photoelectron sheath formation and subsequent fine dust levitation over the sunlit lunar regolith have been investigated by consistently accounting for the continuous interaction of the solar wind ...and solar radiation with the Moon. In deriving the photoelectron sheath, the Poisson equation is coupled with the latitude-dependent population density of the Fermionic photoelectrons. The altitude and latitude profiles of the electric potential, electric field, and electron density within the photoelectron sheath have been derived. A larger sheath is predicted near the terminator compared to the subsolar point. Accounting for the sheath features, the charging of levitating particles under the kinetic balance of anisotropic photoelectron flux, solar radiation, and solar wind plasma has been calculated. The dust charge is coupled with a characteristic sheath field to evaluate the altitude profile of the particle size, displaying levitation under its electrostatic equilibrium with the lunar gravity. Our analysis suggests that in equilibrium, the submicron particles may levitate up to a couple of meters above the lunar surface; for instance, at the subsolar point (0° latitude) 200 and 50 nm particles may float up to an altitude of ∼64 and ∼194 cm, respectively, while at 70° latitude near the terminator these particles are estimated to levitate at an altitude of ∼18 and ∼227 cm, respectively. The floating charged submicron dust may electrostatically interact with the functioning of experiments and can significantly affect the instrument operation.
•Sensible and latent heat storage has been incorporated to solar drying system.•Better product quality has been achieved wi efficient energy conversion.•Performance has been investigated in terms of ...exergy efficiency.•Biomedical evaluation of the product has been performed.•The drying time of the product has been decreased due to continuous drying process.
This paper presents the experimental investigation of indirect forced convection solar dryer integrated with sensible heat storage material (SHSM) and phase change material (PCM) in meteorological environment of Himalayas (latitude 30.91 °N). The iron scrap mixed with gravel is placed on absorber plate and copper tubes comprising of engine oil have been used as SHSM in the solar collector. The Paraffin RT-42 as a PCM has been used in the drying chamber. Experimentations of Valeriana Jatamansi (a medicinal herb) drying have been conducted and its moisture content reduced from initial value of 89% to 9%. Using SHSM and PCM simultaneously the overall drying rate observed 0.051 kg/hr which was almost double as compared to 0.028 kg/hr and 0.018 kg/hr with no use of thermal storage medium and traditional shade drying, respectively. The drying time to reach the saturation level of 9% was recorded as 120 h in comparison to 216 and 336 h, respectively and the dried rhizomes of good quality in terms of essential oil and bio-medical compounds are obtained. From the experimental results rehydration capacity and total Valepotriates were found 7.11 and 3.47% as compared to 6.18 and 3.31%, respectively in case of traditional shade drying. The solar collector without SHSM possess an average energy and exergy efficiency 9.8% and 0.14%, respectively. The respective energy and exergy efficiency achieved with SHSM are 26.10 and 0.81%.
► Long term changes in soil quality and crop productivity with fertilizer and tillage. ► Soil Quality Index (SQI) developed using Principal Components Approach. ► Improved soil quality in No-till, ...Reduced Input compared to conventional management. ► Conservation management improves nutrient availability, soil stability and structure. ► Soil quality concord with microbial nitrogen processing, nitrogen use and leaching.
Intensively cropped agricultural production systems should be managed to improve soil quality and ecological processes and ultimately strengthen system capacity for sustained biological productivity. We examined the long-term changes (>20 years) in soil quality and productivity with incorporation of ecological management principles in a set of intensively managed row crop systems of the upper Midwest, USA. Replicated experimental treatments include corn (maize)–soybean–wheat cropping systems under four different management regimes: (a) conventional tillage and fertilizer/chemical inputs (
Conventional), (b) no tillage with conventional fertilizer/chemical inputs (
No-till), (c) conventional tillage with ∼30% of conventional fertilizer/chemical inputs and a leguminous cover crop (
Reduced Input), and (d) conventional tillage with no fertilizer/chemical input and a leguminous cover crop (
Organic). Effects of these treatments on soils were compared by developing a soil quality index (SQI) from 19 selected soil health indicators. An old field community maintained in early succession provided a benchmark for comparison. Reduction in tillage or fertilizer (
No-till,
Reduced Input and
Organic) resulted in increased SQI and improved crop production. The
No-till (SQI
=
1.02) and
Reduced Input (SQI
=
1.01) systems outperformed
Conventional management (SQI
=
0.92) in nitrogen availability and use efficiency, soil stability and structure improvement, and microbial nitrogen processing. Improvements in soil quality corresponded with increased primary production and crop yield in these systems, illustrating the value of an ecologically defined SQI for assessing the long-term effects of fertility and tillage management regimes in agricultural production systems.
Thermoelectricity has been proven as a potential technology for the conversion of waste heat into usable electricity. It involves primarily three parameters, namely the Seebeck coefficient, ...electrical conductivity, and thermal conductivity. However, there are many other interrelated parameters, such as carrier concentration, mobility, effective mass, multi-valley bands, relaxation time, reduced Fermi energy, phonon modes, scattering parameters, and the number of neighbouring atoms in a given structure. The understanding of these parameters is equally important in order to optimize a high figure of merit (
ZT
). This article addresses the basics of electronic and thermal transport with the help of Boltzmann transport equation, fundamental concepts for the design of thermoelectric (TE) materials, and implementation of several strategies such as alloying, the phonon-glass electron-crystal (PGEC) approach, band engineering and nanostructuring to optimize the
ZT
of materials, and finally ends with a discussion of the future prospects of heat extraction through different heat sources.
Obtaining forensically relevant information beyond who deposited a biological stain on how and under which circumstances it was deposited is a question of increasing importance in forensic molecular ...biology. In the past few years, several studies have been produced on the potential of gene expression analysis to deliver relevant contextualizing information, e.g. on nature and condition of a stain as well as aspects of stain deposition timing. However, previous attempts to predict the time-of-day of sample deposition were all based on and thus limited by previously described diurnal oscillators. Herein, we newly approached this goal by applying current sequencing technologies and statistical methods to identify novel candidate markers for forensic time-of-day predictions from whole transcriptome analyses. To this purpose, we collected whole blood samples from ten individuals at eight different time points throughout the day, performed whole transcriptome sequencing and applied biostatistical algorithms to identify 81 mRNA markers with significantly differential expression as candidates to predict the time of day. In addition, we performed qPCR analysis to assess the characteristics of a subset of 13 candidate predictors in dried and aged blood stains. While we demonstrated the general possibility of using the selected candidate markers to predict time-of-day of sample deposition, we also observed notable variation between different donors and storage conditions, highlighting the relevance of employing accurate quantification methods in combination with robust normalization procedures.This study's results are foundational and may be built upon when developing a targeted assay for time-of-day predictions from forensic blood samples in the future.
Mixing superabsorbents, such as cross-linked polyacrylamides (PAM), with sandy soils may decrease water percolation rates and increase water availability to crops. Four polymers were evaluated for ...their effects on water retention and hydraulic conductivity (HC) in the presence of either tap or distilled water and within sand mixtures. Water retained by the absorbents alone (at low suction) ranged between 200 and 500 kg kg-1 of polymer; water retained by the polymers when mixed with sand ranged between 40 and 140 kg kg-1. Water retained per kilogram of polymer increased with an increase in polymer concentration in the sand while undergoing desorption, but absorbed water decreased with polymer concentration during sorption, indicating an effect of hysteresis and absorption kinetics in the water absorption process. Applying a hydraulic head of tap water initially caused a decrease in the HC, explained by the decrease in the volume of the soil-absorbents mixtures, followed by a steady increase in HC ascribed to drainage of water from the swollen polymer granules that led to an increase in the size of pores available for water flow. Leaching the soil-absorbent mixtures with distilled water, simulating rainwater, increased the volume of the mixtures (due to polymer swelling) and decreased their HC due to pore blockage by the swollen polymer grains. Better understanding of the interaction among absorbents, soil, and water quality may produce an efficient and economic technology for improving the water management of sandy soils.
This review provides a summary of work in the area of ensemble forecasts for weather, climate, oceans, and hurricanes. This includes a combination of multiple forecast model results that does not ...dwell on the ensemble mean but uses a unique collective bias reduction procedure. A theoretical framework for this procedure is provided, utilizing a suite of models that is constructed from the well‐known Lorenz low‐order nonlinear system. A tutorial that includes a walk‐through table and illustrates the inner workings of the multimodel superensemble's principle is provided. Systematic errors in a single deterministic model arise from a host of features that range from the model's initial state (data assimilation), resolution, representation of physics, dynamics, and ocean processes, local aspects of orography, water bodies, and details of the land surface. Models, in their diversity of representation of such features, end up leaving unique signatures of systematic errors. The multimodel superensemble utilizes as many as 10 million weights to take into account the bias errors arising from these diverse features of multimodels. The design of a single deterministic forecast models that utilizes multiple features from the use of the large volume of weights is provided here. This has led to a better understanding of the error growths and the collective bias reductions for several of the physical parameterizations within diverse models, such as cumulus convection, planetary boundary layer physics, and radiative transfer. A number of examples for weather, seasonal climate, hurricanes and sub surface oceanic forecast skills of member models, the ensemble mean, and the superensemble are provided.
Key Points
Improved weather forecasts are possible from a combination of many models to produce a consensus forecast
Model consensus is achieved through using a weighted mean of models; the weights (as many as 10 million ) vary in space and time
Model ensembles utilize a suite of models and the methodology entails the reduction of systematic bias errors of each member model
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