In this study, combined DFT, SCAPS-1D, and wxAMPS frameworks are used to investigate the optimized designs of Cs2BiAgI6 double perovskite-based solar cells. First-principles calculations are employed ...to investigate the structural stability, optical responses, and electronic contribution of the constituent elements in Cs2BiAgI6 absorber material, where SCAPS-1D and wxAMPS simulators are used to scrutinize different configurations of Cs2BiAgI6 solar cells. Here, PCBM, ZnO, TiO2, C60, IGZO, SnO2, WS2, and CeO2 are used as ETL, and Cu2O, CuSCN, CuSbS2, NiO, P3HT, PEDOT:PSS, spiro-MeOTAD, CuI, CuO, V2O5, CBTS, CFTS are used as HTL, and Au is used as a back contact. About ninety-six combinations of Cs2BiAgI6-based solar cell structures are investigated, in which eight sets of solar cell structures are identified as the most efficient structures. Besides, holistic investigation on the effect of different factors such as the thickness of different layers, series and shunt resistances, temperature, capacitance, Mott–Schottky and generation–recombination rates, and J–V (current–voltage density) and QE (quantum efficiency) characteristics is performed. The results show CBTS as the best HTL for Cs2BiAgI6 with all eight ETLs used in this work, resulting in a power conversion efficiency (PCE) of 19.99%, 21.55%, 21.59%, 17.47%, 20.42%, 21.52%, 14.44%, 21.43% with PCBM, TiO2, ZnO, C60, IGZO, SnO2, CeO2, WS2, respectively. The proposed strategy may pave the way for further design optimization of lead-free double perovskite solar cells.
In addition to physical wellbeing, healthy development of a child is when social, emotional and educational needs are met. 1 Ocular diseases among children are related to prenatal-, neonatal-, or ...childhood-underlying causes. 2 Ocular diseases at a young age might significantly affect children's development and eventually interfere with their quality of life. 3–7 Visual defects and blindness among young children are a major concern, as they have numerous negative impacts on individuals, the community, and the country. ...the majority of young children never get an eye examination. The majority of ocular disorders such as amblyopia, unilateral blindness, and strabismus occur at a young age and is the reason why the American Academy of Pediatrics recommends visual screening programs for children younger than 5 years to ensure early detection and appropriate interventions, which, in turn, result in a better quality of life. 12 The objective of this research was to study the epidemiological patterns of ocular morbidity among children younger than 5 years old at three tertiary eye hospitals. STUDY POPULATION AND DATA COLLECTION Patient records of all children younger than 16 years old who attended any of the three hospitals, for any complaint, in 2019 were retrieved (n = 10,886) to collect those of under 5 years of age to estimate their proportion and later to study the pattern of ocular disorder.
CsSnI3 is considered to be a viable alternative to lead (Pb)-based perovskite solar cells (PSCs) due to its suitable optoelectronic properties. The photovoltaic (PV) potential of CsSnI3 has not yet ...been fully explored due to its inherent difficulties in realizing defect-free device construction owing to the nonoptimized alignment of the electron transport layer (ETL), hole transport layer (HTL), efficient device architecture, and stability issues. In this work, initially, the structural, optical, and electronic properties of the CsSnI3 perovskite absorber layer were evaluated using the CASTEP program within the framework of the density functional theory (DFT) approach. The band structure analysis revealed that CsSnI3 is a direct band gap semiconductor with a band gap of 0.95 eV, whose band edges are dominated by Sn 5s/5p electrons After performing the DFT analysis, we investigated the PV performance of a variety of CsSnI3-based solar cell configurations utilizing a one-dimensional solar cell capacitance simulator (SCAPS-1D) with different competent ETLs such as IGZO, WS2, CeO2, TiO2, ZnO, PCBM, and C60. Simulation results revealed that the device architecture comprising ITO/ETL/CsSnI3/CuI/Au exhibited better photoconversion efficiency among more than 70 different configurations. The effect of the variation in the absorber, ETL, and HTL thickness on PV performance was analyzed for the above-mentioned configuration thoroughly. Additionally, the impact of series and shunt resistance, operating temperature, capacitance, Mott–Schottky, generation, and recombination rate on the six superior configurations were evaluated. The J–V characteristics and the quantum efficiency plots for these devices are systematically investigated for in-depth analysis. Consequently, this extensive simulation with validation results established the true potential of CsSnI3 absorber with suitable ETLs including ZnO, IGZO, WS2, PCBM, CeO2, and C60 ETLs and CuI as HTL, paving a constructive research path for the photovoltaic industry to fabricate cost-effective, high-efficiency, and nontoxic CsSnI3 PSCs.
Grain legumes are important sources of proteins, essential micronutrients and vitamins and for human nutrition. Climate change, including drought, is a severe threat to grain legume production ...throughout the world. In this review, the morpho-physiological, physio-biochemical and molecular levels of drought stress in legumes are described. Moreover, different tolerance mechanisms, such as the morphological, physio-biochemical and molecular mechanisms of legumes, are also reviewed. Moreover, various management approaches for mitigating the drought stress effects in grain legumes are assessed. Reduced leaf area, shoot and root growth, chlorophyll content, stomatal conductance, CO2 influx, nutrient uptake and translocation, and water-use efficiency (WUE) ultimately affect legume yields. The yield loss of grain legumes varies from species to species, even variety to variety within a species, depending upon the severity of drought stress and several other factors, such as phenology, soil textures and agro-climatic conditions. Closure of stomata leads to an increase in leaf temperature by reducing the transpiration rate, and, so, the legume plant faces another stress under drought stress. The biosynthesis of reactive oxygen species (ROS) is the most detrimental effect of drought stress. Legumes can adapt to the drought stress by changing their morphology, physiology and molecular mechanism. Improved root system architecture (RSA), reduced number and size of leaves, stress-induced phytohormone, stomatal closure, antioxidant defense system, solute accumulation (e.g., proline) and altered gene expression play a crucial role in drought tolerance. Several agronomic, breeding both conventional and molecular, biotechnological approaches are used as management practices for developing a drought-tolerant legume without affecting crop yield. Exogenous application of plant-growth regulators (PGRs), osmoprotectants and inoculation by Rhizobacteria and arbuscular mycorrhizal fungi promotes drought tolerance in legumes. Genome-wide association studies (GWASs), genomic selection (GS), marker-assisted selection (MAS), OMICS-based technology and CRISPR/Cas9 make the breeding work easy and save time in the developmental cycle to get resistant legumes. Several drought-resistant grain legumes, such as the chickpea, faba bean, common bean and pigeon pea, were developed by different institutions. Drought-tolerant transgenic legumes, for example, chickpeas, are developed by introgressing desired genes through breeding and biotechnological approaches. Several quantitative trait loci (QTLs), candidate genes occupying drought-tolerant traits, are identified from a variety of grain legumes, but not all are under proper implementation. Hence, more research should be conducted to improve the drought-tolerant traits of grain legumes for avoiding losses during drought.
This paper proposes a new calibration estimator for population variance within a stratified two-phase sampling design. It takes into account random non-response and measurement errors, specifically ...applying this method to estimate the variance in Gas turbine exhaust pressure data. The study integrates additional information from two highly positively correlated auxiliary variables to develop a general class of estimators tailored for the stratified two-phase sampling scheme. The properties of these estimators, in terms of their biases and mean square errors, have been thoroughly examined and extensively analyzed through numerical and simulation studies. Furthermore, the calibrated weights of the strata are derived. The proposed estimators outperform the natural estimator of population variance. Finally, suitable recommendations have been made for survey statisticians intending to apply these findings to real-life problems.
Open spaces in tropical climates are highly exposed to solar radiation. These conditions will influence the outdoor energy budget, leading to an increased heat island effect and reduced human thermal ...comfort. Trees, however, can influence the microclimate through radiation control that indirectly reduces direct radiation uptake and glare by humans and buildings. This condition affects building energy budget and human thermal comfort. This study compares the effectiveness of
Mesua ferrea L. and
Hura crepitans L. in shade creation and radiation modification in improving human thermal comfort. The study employed two methods: (i) a field measurement procedure and (ii) a computer-based sun-shading analysis using ECOTECT. The results from this study indicate that both
M. ferrea L. and
H. crepitans L. contribute significantly to direct thermal radiation modification below their canopies. The average solar filtration under the tree canopy for
M. ferrea L. was 93%, with 5% canopy transmissivity, 6.1% of leaf area index (LAI) and 35% of shade area. For
H. crepitans L. the average heat filtration under the canopy was 79%, with transmissivity of 22%, LAI of 1.5 and 52% of shade area. Thus, the study found that
M. ferrea L. was more significant as a thermal radiation filter than
H. crepitans L., due to the former's denser foliage cover and branching habit. This significant filtration capability contributes to reduce more terrestrial radiation, cooling the ground surfaces by promoting more latent heat, reducing air temperature by promoting more evapotranspiration and effectively improves outdoor thermal comfort in tropical open spaces.
The power conversion efficiency (PCE) of cesium lead halide (CsPbX3, X = l, Br, and Cl)-based all-inorganic perovskite solar cells (PSCs) is still struggling to compete with conventional ...organic–inorganic halide perovskites. A combined material and device-related analysis is much needed to understand the working principle to explore the efficiency potential of CsPbX3-based PSCs. Therefore, here, density functional theory (DFT) and SCAPS-1D-based studies were reported to evaluate the photovoltaic (PV) performance of CsPbBr3-based PSCs. DFT is first applied to assess and extract structural and optoelectronic properties (band structure, density of states, Fermi surface, and absorption coefficient) of the considered absorber layer. The calculated electronic band gap (E g) of the CsPbBr3 absorber was 1.793 eV, which matched well with the earlier computed theoretical value. Additionally, the Pb 6p orbital contributed largely to the calculated density of states (DOS), and the electronic charge density map showed that the Pb atom acquired the majority of charges. In order to examine the optical response of CsPbBr3, optical characteristics were computed and correlated with electronic properties for its probable photovoltaic applications. Fermi surface computation showed multiband characters. Furthermore, to look for a suitable combination of the charge transport layer, a total of nine HTLs (Cu2O, CuSCN, P3HT, PEDOT:PSS, Spiro-MeOTAD, CuI, V2O5, CBTS, and CFTS) and six ETLs (TiO2, PCBM, ZnO, C60, IGZO, and WS2) are used considering the experimental E g (2.3 eV). The best power conversion efficiency (PCE) of 13.86% is reported for TiO2 and CFTS in combination with the CsPbBr3 absorber. The effects of operating temperature, series and shunt resistances, Mott–Schottky, capacitance, generation and recombination rates, quantum efficiency, and current–voltage density were also examined. The resulting PV properties were also compared with previously published data. Results reported in this study will pave the way for the development of high-efficiency all-inorganic CsPbBr3-based solar cells in the future.
In this study, we investigated the potential of CsPbI3 as an absorber material to be used in perovskite solar cells (PSCs). To optimize the device, we used TiO2 as the electron transport layer and ...copper barium thiostannate (CBTS) as the hole transport layer in the CsPbI3-based PSC, and employed SCAPS-1D software. We initially tested 10 different back metal contacts (BMCs) to identify the most suitable one for the primary device. After optimization of the BMC, the best-optimized device structure, ITO/TiO2/CsPbI3/CBTS/Ni, achieved a power conversion efficiency of 17.91%. We then evaluated the impact of the absorber thickness, acceptor density, and defect density on the device performance. We also analyzed the effect of changing the thickness, charge-carrier density, and defect density of the CsPbI3, TiO2, and CBTS layers, as well as the interfacial defect densities at the CBTS/CsPbI3 and CsPbI3/TiO2 interfaces, to further optimize device performance. This resulted in an improved efficiency of 19.06% for the ITO/TiO2/CsPbI3/CBTS/Ni device with HTL, compared to 18.17% without HTL. We also analyzed the impacts of operating temperature, series resistance, and shunt resistance on the final optimized device performance, as well as its capacitance–voltage, generation and recombination rate, current density–voltage (J–V), and quantum efficiency (QE) features. The results of these simulations provide valuable insights for the experimental fabrication of an efficient CsPbI3-based inorganic PSC.
•The electrical power and efficiency are affected by fuel–air equivalence ratio.•The radiant efficiency is significantly attenuated at very lean and rich mixtures.•Flame stability is attained over ...wide range of fuel–air equivalence ratio.•The carbon monoxide and nitrogen oxides were insensitive to the fuel blends.•Cost-performance analysis reveals excellent agreement with established systems.
Fast depleting reserves in conservative energy resources are principal motivation for developing highly efficient energy conversion systems. Thermoelectric and thermophotovoltaic devices are rapidly becoming promising solutions and they have revolutionized combustion-driven power generators. A combined thermoelectric and thermophotovoltaic power system was demonstrated experimentally and featured a gravity-fed fuel supply to attain stable combustion. Our aim was to better understand the influence of a fuel − air equivalence ratio on the performance and combustion characteristics of the combined system. The fuel − air equivalence ratio was varied for four types of fuel blends: 100% kerosene, 50%/50% vegetable cooking oil − kerosene, 80%/20% vegetable cooking oil − kerosene, and 95%/5% vegetable cooking oil − kerosene. The electrical power output varied almost linearly in a lean mixture of combustion. The peak values of the electrical power and efficiency skewed slightly rich of the stoichiometry, and these values decayed gradually in the rich mixtures. Detailed temperature profiles revealed efficient transfer of heat from the stabilized porous combustion to the input of both the thermoelectric and thermophotovoltaic cells. The carbon monoxide and nitrogen oxides emissions steeply increased beyond a stoichiometric value, and these emissions were marginally affected by the changes in the vegetable cooking oil contents. The concept appears to be attractive because the pertinent cost-performance analysis indicated a reasonably good similarity compared with other systems reported in the literature. Future advances in the combined power system can be realized by heightening key performance gains as well as effective cost-benefit strategies.
Preeclampsia is a severe placenta-related pregnancy disorder that is generally divided into two subtypes named early-onset preeclampsia (onset <34 weeks of gestation), and late-onset preeclampsia ...(onset ≥34 weeks of gestation), with distinct pathophysiological origins. Both forms of preeclampsia have been associated with maternal systemic inflammation. However, alterations in the placental immune system have been less well characterized. Here, we studied immunological alterations in early- and late-onset preeclampsia placentas using a targeted expression profile approach. RNA was extracted from snap-frozen placenta samples (healthy n=13, early-onset preeclampsia n=13, and late-onset preeclampsia n=6). The expression of 730 immune-related genes from the Pan Cancer Immune Profiling Panel was measured, and the data were analyzed in the advanced analysis module of nSolver software (NanoString Technology). The results showed that early-onset preeclampsia placentas displayed reduced expression of complement, and toll-like receptor (TLR) associated genes, specifically TLR1 and TLR4. Mast cells and M2 macrophages were also decreased in early-onset preeclampsia compared to healthy placentas. The findings were confirmed by an immunohistochemistry approach using 20 healthy, 19 early-onset preeclampsia, and 10 late-onset preeclampsia placentas. We conclude that the placental innate immune system is altered in early-onset preeclampsia compared to uncomplicated pregnancies. The absence of these alterations in late-onset preeclampsia placentas indicates dissimilar immunological profiles. The study revealed distinct pathophysiological processes in early-onset and late-onset preeclampsia placentas and imply that a tailored treatment to each subtype is desirable.
PDF
