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Abstract Three-dimensional (3D) metal halide perovskite solar cells (PSCs) have a power conversion efficiency that is now comparable with conventional silicon solar cells. For PSC applications to succeed in the market, long-term reliability under open-air conditions is essential. Recent experiments have shown that two-dimensional (2D) perovskites seem to exhibit good stability due to the presence of hydrophobic organic spacers, but 2D PSCs are incapable of generating and transporting a large amount of charge due to their extended optical bandgaps. Mixed dimensional perovskites with dimension lies between 2D and 3D recently became a promising candidate to sustain long-term stability and high performances concurrently to address this obstacle. The current research article presents the finding of simulation-based studies performed on novel device architecture consisting of ITO/Nb-Ti2O3/3D Perovskite/2D Perovskite/Spiro-OMeTAD/Au. Using optical simulation features of SCAPS, absorption of light is computed in the proposed device. The computational results show that the thickness of the 2D perovskite layer badly affects the solar cell parameters. A thin 2D perovskite behaves as a capped coating that avoids the deterioration of 3D perovskite in open-air environments. The effect of a multivalent defect in the 3D perovskite layer is mathematically modelled, and their impact on overall performance parameters are analyzed. The findings are compared to the same configuration results, except where the absorber layer’s multivalent defect has been substituted by a neutral defect of the same defect density of about (1011 cm−3). Results show that the multivalent defect leads to an underestimation of the efficiency by 4.2%.

Abstract This study investigates the possibility of using and developing hydrokinetic power to supply reliable, affordable and sustainable electricity to rural, remote and isolated loads in rural South Africa where reasonable water resource is available. Simulations are performed using the Hybrid Optimization Model for Electric Renewable (HOMER) and the results are compared to those from other supply options such as standalone Photovoltaic system (PV), wind, diesel generator (DG) and grid extension. Finally the paper points out some major challenges that are facing the development of this technology in South Africa.

To assess the sustainability of waste management scenario with energy recovery, it is necessary to carry out an adequate analysis of all influential criteria. The main problem in the analysis is to determine the indicators that clearly and fully sublimate the most important influential factors. The model for the assessment of the sustainability of waste treatment scenarios based on multi-criteria analysis AHP (analytic hierarchy process) method is developed. The model predicts an increase in the number of indicators, if it found that a selected number of indicators are not sufficient to distinguish between scenarios and new criterion for the selection of indicators: the relevance of the indicator for certain waste treatment. The model is verified in the case study the city of Nis. Four scenarios were selected and examined: business as usual scenario (landfilling of waste) and the other are created as scenarios with energy recovery and recourses preserving: composting organic waste with recycling inorganic waste, incineration of waste and anaerobic digestion of waste. The assessment of the sustainability of waste treatment scenarios was made in several steps. It is found that the best sustainable scenario is composting of organic and recycling of inorganic waste.

Poria cocos (Schw.) Wolf, an important medicinal and food fungus, is well known in East Asia. Due to growing market demand, long cultivation period, and consumption of pine trunk during cultivation, developing alternative methods for producing P. cocos and/or its active components is of interest. In the present study, the effects of different culture methods on biomass and accumulation of four triterpenoids were investigated. The ethanol extract of fermented mycelium (EFM) was orally administered to rats. Urine output and concentrations of electrolytes (Na+, K+, and Cl-) were measured. Our results showed that mycelia grew better under continuous shaking culture condition (7.5 g DW·L-1), and higher triterpenoid levels were accumulated in two-stage culture (112 mg·L-1, 2.03%). The optimal starting time of static culture for triterpenoid yield was 4th d after shaking culture. Single administration of middle and high dose of EFM significantly increased urine output, Na+ and Cl- excretion, and Na+/K+ ratio. These results suggested that ethanol extract of cultured mycelia showed significant diuretic activity in rats and two-stage culture of P. cocos could be an alternative way to produce mycelia and triterpenoids.

Abstract Egg yolk-derived P and N dual doped nano carbon capsules (PNCCs) have been synthesized and used as lithium ion battery anodes. The application of egg yolk as the carbon source is a new and environmental-friendly approach for biomass recycling. The reversible capacity of half cells made of PNCCs is as high as ~770 mA h g−1 at a current density of 0.5 A g−1 with considerable rate capacity and cycling stability. PNCCs show a capsule-like structure, which provide extra edges and active sites for lithium intercalation. The heteroatom doping also introduce defects and disorder, which increases the electrochemical activity and creates more active sites for lithium insertion.

Abstract Nowadays, natural gas is viewed as the solution to the problem of energy supply for Latin America, Europe and North America for the next few decades; Brazil is increasingly becoming dependent upon the Bolivian natural-gas supply — many industries and some entrepreneurs are deciding to construct industrial cogeneration systems and new thermal power-stations burning natural gas because of its low environmental impact and attractive price. However, natural gas is a finite resource: this will cause, in the future, an increase of its unit price. This paper details questions involved in the energy generation and presents solid-waste burning as a possible alternative fuel for the future, especially in the context of cogeneration practice in which the thermal and electric energy are used primarily for the industries located in an industrial district. Two cogeneration schemes are proposed for the burning of municipal solid wastes, associated or not with natural gas, and their technical and economic feasibilities are examined.

Recycling of anaerobically-digested thin stillage within a corn-ethanol plant may result in the accumulation of nutrients of environmental concern in animal feed coproducts and inhibitory organic materials in the fermentation tank. Our focus is on anaerobic digestion of treated (centrifugation and lime addition) thin stillage. Suitability of digestate from anaerobic treatment for reuse as process water was also investigated. Experiments conducted at various inoculum-to-substrate ratios (ISRs) revealed that alkalinity is a critical parameter limiting digestibility of thin stillage. An ISR level of 2 appeared optimal based on high biogas production level (763 mL biogas/g volatile solids added) and organic matter removal (80.6% COD removal). The digester supernatant at this ISR level was found to contain both organic and inorganic constituents at levels that would cause no inhibition to ethanol fermentation. Anaerobic digestion of treated-thin stillage can be expected to improve the water and energy efficiencies of dry grind corn-ethanol plants.

Fuels based on renewable energy sources (RES) such as a variety of first and second generation biofuels as well as electricity and hydrogen from RES, are considered an important means of coping with the environmental problems of transport. The objective of this paper is to investigate the “renewable fuels” from economic, energetic and ecological perspective within a dynamic framework until 2050. The key results show that all fuels analysed have lower CO2 emissions than gasoline, but drawbacks include the high costs of hydrogen- and electricity-driven vehicles. By 2050 however these costs could be reduced due to technological learning effects and efficient policy measures (e.g. CO2-based tax). We conclude that “renewable fuels” will only play a significant role if CO2 taxes, intensified R&D and technological learning are strategically implemented.