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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120387, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34555697

RESUMO

Dye-sensitized solar cells (DSSCs) have recently received a significant attention as possible sources of renewable energy. As a result, a significant effort is being made to develop organic dyes for highly power conversion efficient DSSCs, in order to overcome the disadvantages of previous solar cell systems, such as cost reduction, weight reduction, and production methods that minimize environmental pollution. As shown by multiple recent research publications, computational techniques such as quantitative structure-property relationship (QSPR) modeling may aid in the development of suitable dyes for DSSCs satisfying many fundamental desired characteristics. The current report provides robust, externally verified QSPR models for five chemical classes of organic dyes (Triphenylamines, Phenothiazines, Indolines, Porphyrins and Coumarins) based on experimentally determined absorption maxima values. The size of the dye data points utilized to develop the models is the largest known to date. The QSPR models were constructed using only two-dimensional descriptors with clear physicochemical meaning. Using the best subset selection approach, we built 5, 3, 4, 3 and 2 descriptor models for the Triphenylamine, Phenothiazine, Indoline, Porphyrin and Coumarin classes, respectively. The models were validated both internally and externally, and then consensus predictions were made for specific categories of dyes using the developed partial least squares (PLS) models, and the "Intelligent consensus predictor" tool (http://teqip.jdvu.ac.in/QSAR_Tools/) was used to determine whether the quality of test set compound predictions can be improved through the "intelligent" selection of multiple PLS models. We identified from the insights gained from the developed models several chemical attributes that are important in enhancing the absorption maxima. Thus, our study may be utilized to predict the λmax values of novel or untested organic dyes and to give insights that will aid in the development of new dyes for use in solar cells with increased λmax values and enhanced power conversion efficiency.


Assuntos
Porfirinas , Energia Solar , Corantes , Relação Quantitativa Estrutura-Atividade , Luz Solar
2.
Chemosphere ; 286(Pt 1): 131557, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34293562

RESUMO

Solar zerovalent iron (ZVI) was studied at circumneutral pH in combination with hydrogen peroxide and persulfate for removal of imidacloprid as a model contaminant in natural water. Three commercial ZVI sources, steel wool (ZVI-SW) and two iron micro-powders (ZVI-MS and ZVI-S) were independently evaluated. First, different ZVI corrosion conditions were tested in contact with air, exposed to natural solar radiation and with addition of oxidants, such as H2O2 and S2O82-, demonstrating the importance of released iron. Then, the technical feasibilities of solar/H2O2/ZVI and solar/S2O82-/ZVI were assessed for the elimination of 1 mg/L of imidacloprid. In general, H2O2 concentrations and treatment times were high. Only ZVI-MS (1 mM) reached 80% imidacloprid degradation after 157 min and 3 mM (102 mg/L) of H2O2. Solar/S2O82-/ZVI performance was better, reaching >80% imidacloprid degradation in <60 min with 1 mM (192 mg/L) S2O82- for all ZVI sources. Efficiency was highest with ZVI-MS, which was therefore selected for feasibility testing of a microcontaminant (MC) mixture containing 100 µg/L each of atrazine, carbendazim, imidacloprid and thiamethoxam with both solar/oxidizing agents/ZVI. H2O2 took 180 min to achieve 76% degradation of the sum of MCs, while 80% total degradation was reached after 69 min by adding S2O82-, confirming its higher efficiency. Finally, this study showed that ZVI in combination with solar radiation does not enhance significantly the photocatalytic cycle.


Assuntos
Energia Solar , Poluentes Químicos da Água , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Ferro , Água , Poluentes Químicos da Água/análise
3.
Chemosphere ; 286(Pt 1): 131657, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34351279

RESUMO

The photocatalytic fuel cell (PFC) is a promising energy conversion technology for effective solar energy utilization, wastewater treatment, and electricity generation by photoelectrochemical reactions. Nevertheless, the discharging current output and stability of the PFC are still plagued by the low photoelectron conversion efficiency and time-varying light intensity, respectively. Herein, we integrated a RuO2 capacitive layer and a TiO2 photocatalytic layer into a capacitive photoanode, finally designing a PFC with the capacitive photoanode. Not only can the successful integration of the capacitive layer augment the discharging current, but it can also balance the solar intensity fluctuation by the ability of electron storage. The capacitive photoanode showed a high areal capacitance of 1040.7 mFcm-2 at a current density of 0.5 mAcm-2, was continuously charged and discharged for 1000 cycles, and maintained 87 % of the original capacitance after cycles. The superior rate capability, high capacitance, and good cycle performance of the capacitive photoanode originate from the "crack mud" structure in the capacitive layer. The discharging current of the capacitive photoanode was 32.0 mAcm-2 under one sun illumination, and the electrochemical performance of the capacitive photoanode was better than that of the conventional TiO2 photoanode. The capacitive photoanode PFC possessed a maximum short-circuit current of 300.0 µA⋅cm-2 at the beginning of discharge, which is independent of the light intensity. The capacitive photoanode PFC adopts a new working mode and provides a unique solution for the practical application of PFC.


Assuntos
Energia Solar , Purificação da Água , Eletricidade , Eletrodos , Luz
4.
Environ Pollut ; 292(Pt A): 118352, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637823

RESUMO

Lithopone pigments are an important group of white inorganic pigments, with production exceeding 240,000 tons/year in China. Nevertheless, our understanding of its environmental behavior is still limited. In this work, we reported the fast and extensive release of Zn2+ from the commercial lithopone pigment under solar exposure. The lithopone pigment released 40.97% of its total Zn within 24-h simulated sunlight exposure, generating a significant amount of nanoparticles. The commercial lithopone pigment had bandgap energy of 3.63 eV. It can be excited within the solar spectrum (wavelength <342 nm). As suggested by the photocurrent and surface photovoltage results, the pigment generated electrons and holes with good separation and transfer efficiency upon solar irradiation. The pigment also produced hydroxyl radical and superoxide by the oxidation of surface-bound OH- and H2O by the holes and direct transfer of the electrons to oxygen molecules. The photogenerated holes can oxidize the pigment, leading to its photo-dissolution and consequently the release of Zn2+. The water chemistry, including pH, coexisting anions, and organic carbons, influenced the photo-dissolution kinetics of the pigment by changing the valence band edge, forming stable precipitates, competing for the holes, and screening effect. The release of Zn2+ from the commercial lithopone pigment was fast and extensive under natural conditions, with 35.16% Zn released within 6-h solar exposure. Our results highlighted the crucial role of photochemistry in the environmental risk assessments and regulations of commercial lithopone pigments.


Assuntos
Energia Solar , Zinco , Compostos Orgânicos , Fotoquímica , Luz Solar
5.
Sci Total Environ ; 803: 149991, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482137

RESUMO

The green powering of electrochemically-assisted soil remediation processes had been strongly discouraged. Low remediation efficiencies have been reported as a consequence of the reversibility of the transport processes when no power is applied to the electrodes, due to the intermittent powering of renewable sources. However, it has been missed a deeper evaluation from the environmental point of view. This work goes further and seeks to quantify, using life cycle assessment tools, the environmental impacts related to the electro-kinetic treatments powered by different sources: grid (Spanish energy mix), photovoltaic and wind sources. The global warming potential and the ozone depletion showed higher environmental impacts in case of using green energies, associated with the manufacturing of the energy production devices. In contrast to that, results pointed out the lowest water consumption for the treatment powered with solar panels. The huge water requirements to produce energy, considering a Spanish energy mix, drop the sustainability of this powering strategy in terms of water footprint. Regarding toxicities, the pollutant toxicity was highly got rid of after 15 days of treatment, regardless the powering source used. Nevertheless, the manufacturing of energy and green energy production devices has a huge impact into the toxicity of the remediation treatments, increasing massively the total toxicity of the process, being this effect less prominent by the electro-kinetic treatment solar powered. In view of the overall environmental impact assessed, according to mid and endpoint impact categories, it can be claimed that, despite the high energy requirements and affectation to the global warming potential, the use of solar power is a more sustainable alternative to remediate polluted soils by electrochemical techniques.


Assuntos
Recuperação e Remediação Ambiental , Energia Solar , Fontes de Energia Elétrica , Meio Ambiente , Solo , Vento
6.
J Hazard Mater ; 421: 126751, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34343880

RESUMO

One of the challenges in research into photoelectrocatalytic (PEC) degradation of pollutants is finding the appropriate photoanode material, which has a significant impact on the process efficiency. Among all others, photoelectrodes based on an ordered TiO2 nanotube arrays are a promising material due to well-developed surface area and efficient charge separation. To increase the PEC activity of this material, the SILAR method was used to decorate Ti/TiO2 nanotubes by PbS quantum dots (QD). The ifosfamide (IF) degradation rate constants was twice as higher for PbS-Ti/TiO2 (0.0148 min-1) than for Ti/TiO2 (0.0072 min-1). Our research showed the highest efficiency of PEC degradation of drugs using IIIPbS-Ti/TiO2 made with 3 SILAR cycles (PbS QD size mainly 2-4 nm). The 4 and 6 of SILAR cycles resulted in the aggregation of PbS nanoparticles on the Ti/TiO2 surface and decreased IF PEC degradation rate to 0.0043 and 0.0033 min-1, respectively. Research on PEC mechanism has shown that the drugs are degraded mainly by the activity of photogenerated holes and hydroxyl radicals. In addition, the identified drug intermediates made possible to propose a degradation pathways of anticancer drugs and the ecotoxicity test show no inhibition of Lemna minor growth of treated solutions.


Assuntos
Antineoplásicos , Nanotubos , Pontos Quânticos , Energia Solar , Titânio
7.
Artigo em Inglês | MEDLINE | ID: mdl-34769669

RESUMO

With the growth in China's economic GDP, energy consumption has increased year by year. The energy demand of rural residential buildings is 223 million tons of standard coal equivalent, accounting for 24% of the national energy demand. Therefore, an energy-saving design for rural residences is necessary. This research took the traditional residences in southern Shaanxi as the research object and combined the cooking methods in southern Shaanxi with solar heating, proposing a sunlight heating system with an additional firewall. The system is composed of a firewall system and a sunlight system. The combination of the two systems prolongs the heating time and makes up for the lack of intermittent heating. The firewall principle involves using the heat generated by cooking through the heat storage and heat release capacity of the wall, and using the principle of heat radiation and convection to increase the indoor temperature. Meanwhile, the principle of the additional sunlight room involves using the external facade of the building to establish an additional sunlight room, by absorbing the heat radiation of the sun and using the principle of heat transfer from the wall. The rapid loss of indoor hot air is avoided, the heating time is prolonged, and part of the heat is retained, thereby improving the heating efficiency. A model was established based on the typical residential model in southern Shaanxi, and the presence or absence of solar radiation on the wall was used as the research variable. Using ANSYS software to simulate the analysis, it is concluded that the firewall-sunlight system can extend the heating time and meet the continuous heating demand, and the heating effect is better than that of the firewall heating system alone. When the walls have solar radiation, the annual heat load reduction rate of the buildings under the new system is 20.21%. When the walls do not have solar radiation, the annual heat load reduction rate of the buildings under the new system is 8.56%.


Assuntos
Calefação , Energia Solar , Carvão Mineral , Habitação , Luz Solar
8.
Artigo em Inglês | MEDLINE | ID: mdl-34639775

RESUMO

As part of the UV-Indien project, a station for measuring ultraviolet radiation and the cloud fraction was installed in December 2019 in Moroni, the capital of the Comoros, situated on the west coast of the island of Ngazidja. A ground measurement campaign was also carried out on 12 January 2020 during the ascent of Mount Karthala, located in the center of the island of Ngazidja. In addition, satellite estimates (Ozone Monitoring Instrument and TROPOspheric Monitoring Instrument) and model outputs (Copernicus Atmospheric Monitoring Service and Tropospheric Ultraviolet Model) were combined for this same region. On the one hand, these different measurements and estimates make it possible to quantify, evaluate, and monitor the health risk linked to exposure to ultraviolet radiation in this region and, on the other, they help to understand how cloud cover influences the variability of UV-radiation on the ground. The measurements of the Ozone Monitoring Instrument onboard the EOS-AURA satellite, being the longest timeseries of ultraviolet measurements available in this region, make it possible to quantify the meteorological conditions in Moroni and to show that more than 80% of the ultraviolet indices are classified as high, and that 60% of these are classified as extreme. The cloud cover measured in Moroni by an All Sky Camera was used to distinguish between the cases of UV index measurements taken under clear or cloudy sky conditions. The ground-based measurements thus made it possible to describe the variability of the diurnal cycle of the UV index and the influence of cloud cover on this parameter. They also permitted the satellite measurements and the results of the simulations to be validated. In clear sky conditions, a relative difference of between 6 and 11% was obtained between satellite or model estimates and ground measurements. The ultraviolet index measurement campaign on Mount Karthala showed maximum one-minute standard erythemal doses at 0.3 J·m-2 and very high daily cumulative erythemal doses, at more than 80 J·m-2. These very high levels are also observed throughout the year and all skin phototypes can exceed the daily erythemal dose threshold, at more than 20 J·m-2.


Assuntos
Ozônio , Energia Solar , Comores , Eritema , Humanos , Ozônio/análise , Raios Ultravioleta
9.
Sensors (Basel) ; 21(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34640662

RESUMO

Over the past few decades, the concentrating photovoltaic systems, a source of clean and renewable energy, often fully integrated into the roof structure, have been commonly installed on private houses and public buildings. The purpose of those panels is to transform the incoming solar radiation into electricity thanks to the photovoltaic effect. The produced electric power is affected, in the first instance, by the solar panel efficiency and its technical characteristics, but it is also strictly dependent on site elevation, the meteorological conditions and on the presence of the atmospheric constituents, i.e., clouds, hydrometeors, gas molecules and sub-micron-sized particles suspended in the atmosphere that can scatter and absorb the incoming shortwave solar radiation. The Aerosol Optical Depth (AOD) is an adimensional wavelength-dependent atmospheric column variable that accounts for aerosol concentration. AOD can be used as a proxy to evaluate the concentration of surface particulate matter and atmospheric column turbidity, which in turn affects the solar panel energy production. In this manuscript, a new technique is developed to retrieve the AOD at 550 nm through an iterative process: the atmospheric optical depth, incremented in steps of 0.01, is used as input together with the direct and diffuse radiation fluxes computed by Fu-Liou-Gu Radiative Transfer Model, to forecast the produced electric energy by a photovoltaic panel through a simple model. The process will stop at that AOD value (at 550 nm), for which the forecast electric power will match the real produced electric power by the photovoltaic panel within a previously defined threshold. This proof of concept is the first step of a wider project that aims to develop a user-friendly smartphone application where photovoltaic panel owners, once downloaded it on a voluntary basis, can turn their photovoltaic system into a sunphotometer to continuously retrieve the AOD, and more importantly, to monitor the air quality and detect strong air pollution episodes that pose a threat for population health.


Assuntos
Poluição do Ar , Energia Solar , Aerossóis , Poluição do Ar/análise , Atmosfera , Material Particulado
10.
Plant Sci ; 312: 111046, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34620444

RESUMO

Barren stalks and kernel abortion are the major obstacles that hinder maize production. After many years of inbreeding, our group produced a pair of barren stalk/non-barren stalk near-isogenic lines SN98A/SN98B. Under weak light stress, the barren stalk rate is up to 98 % in SN98A but zero in SN98B. Therefore, we consider that SN98A is a weak light-sensitive inbred line whereas SN98B is insensitive. In the present study, the near-isogenic lines SN98A/SN98B were used as test materials to conduct cytological and photosynthetic physiological analyses of the physiological mechanism associated with the differences in maize barren stalk induced by weak light stress. The results showed that weak light stress increased the accumulation of reactive oxygen species (ROS), decreased the function of chloroplasts, destroyed the normal rosette structure, inhibited photosynthetic electron transport, and enhanced lipid peroxidation. The actual photochemical quantum efficiency for PSI (Y(I)) and PSII (Y(II)), relative electron transfer rate for PSI (ETR(I)) and PSII (ETR(II)), and the P700 activities decreased significantly in the leaves of SN98A and SN98B under weak light stress, where the decreases were greater in SN98A than SN98B. After 10 days of shading treatment, the O2·- production rate, H2O2 contents, the yield of regulated energy dissipation (Y(NPQ)), the donor side restriction for PSI (Y(ND)) and the quantum efficiency of cyclic electron flow photochemistry were always higher in SN98A than SN98B, and the antioxidant enzyme activities were always lower in SN98A than those in SN98B. These results show that SN98B has a stronger ability to remove ROS at its source, and maintain the integrity of the structure and function of the photosynthetic system. This self-protection mechanism is an important physiological reason for its adaptation to weak light.


Assuntos
Adaptação Ocular/genética , Adaptação Ocular/efeitos da radiação , Fotossíntese/efeitos da radiação , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/efeitos da radiação , Energia Solar , Zea mays/genética , Zea mays/efeitos da radiação , Diferenciação Celular/genética , Diferenciação Celular/efeitos da radiação , Cloroplastos/genética , Cloroplastos/efeitos da radiação , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/efeitos da radiação , Transporte de Elétrons/genética , Transporte de Elétrons/efeitos da radiação , Variação Genética , Genótipo , Fotossíntese/genética , Zea mays/crescimento & desenvolvimento
12.
J Phys Chem Lett ; 12(37): 8972-8979, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34506148

RESUMO

We present two-dimensional white-light spectroscopy (2DWL) measurements of binary and ternary bulk heterojunctions of the polymer donor PM6 mixed with state-of-the-art nonfullerene acceptors Y6 or IT4F. The ternary film has a shorter lifetime and faster spectral diffusion than either of the binary films. 2D line shape analysis of the PM6 ground state bleach with a Kubo model determines that all three films have similar amplitudes of fluctuations (Δ = 0.29 fs-1) in their transition frequencies, but different relaxation times (ranging from 102 to 24 fs). The ternary film exhibits faster dynamics than either of the binary films. The short lifetime of the ternary blend is consistent with increased photoexcitation transfer and the fast frequency fluctuations are consistent with structural dynamics of aliphatic side chains. These results suggest that the femtosecond fluctuations of PM6 are impacted by the choice of the acceptor molecules. We hypothesize that those dynamics are either indicative, or perhaps the initial source, of structural dynamics that ultimately contribute to solar cell operation.


Assuntos
Polímeros/química , Energia Solar , Microscopia de Força Atômica , Espectrofotometria
13.
Artigo em Inglês | MEDLINE | ID: mdl-34574596

RESUMO

BACKGROUND: This study tested a theoretical model including key psychosocial factors that could be involved in the acceptance of different energy sources (gas, wind, and solar); Methods: Participants were 550 adult residents of the Canary Islands. Variables assessed were information and utility (normative motives), perceived risk and perceived benefits (gain motives), and negative and positive emotions (hedonic motives), with acceptance of each of the three energy sources as outcome variables; Results: It was found that renewable energies (wind and solar) had a higher degree of acceptance than non-renewable energy (gas). The proposed model satisfactorily explained the social acceptance of the three energy sources, although the psychosocial factors involved differed by energy source. The gain motives, mainly perceived benefits, were associated to a greater extent with gas energy, whereas normative motives, such as utility, and hedonic motives, such as positive emotions, had greater weight for renewables. Gender differences in gas energy were found. Information about renewable energy increased positive emotions and acceptance, whereas information about fossil fuel-based energy generated more negative emotions and perceived risk, decreasing acceptance; Conclusions: Utility, perceived benefits and positive emotions were involved on the acceptance of both renewables and non-renewables. The theoretical model tested seems to be useful for understanding the psychosocial functioning of the acceptance of the various energy sources as an essential aspect for the transition of non-renewable to renewable energies.


Assuntos
Energia Solar , Vento , Humanos , Distância Psicológica , Energia Renovável , Espanha
14.
J Chem Inf Model ; 61(10): 5098-5116, 2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-34587740

RESUMO

Cosensitization of the semiconducting electrode in dye-sensitized solar cells (DSCs), with two or more light-harvesting dyes, is a chemical fabrication method that aims to achieve a panchromatic absorption spectrum emulating that of the solar emission spectrum. In this paper, SQ02 and BP-2 cosensitizers have been investigated, as isolated monomers/dimer and adsorbed monomers/dimer on the TiO2 (101) anatase surface, by employing density functional theory (DFT) and time-dependent DFT calculations. Computed results showed that the dominant electron injection pathway is direct injection from each dye into the conduction band of TiO2. The almost complete spectral overlap between the simulated absorption spectrum of BP-2 and fluorescence emissions of SQ02 implies that excitation energy transfer occurs between cosensitizers via the trivial reabsorption mechanism. However, the results showed very limited unidirectional intermolecular charge transfer (CT) from SQ02 dye to BP-2 dye (0.04 |e-|). Therefore, this study also presents a stepwise molecular engineering of BP-2 dye, aiming at optimizing the cosensitization functionality. First, 14 redesigned dye candidates are reported to identify dyes with photophysical properties matching the requirements for efficient DSCs. Second, the four most promising dyes are shortlisted for testing as cosensitizers with the SQ02 dye. The molecular design factors of cosensitization that need validation are chemical compatibility, availability of CT between cosensitizers, and complementarity of the absorption spectra. This screening suggests the judicious choice of the modeled difluorenyl amine donor-based dye (BP-D4) as a very promising cosensitizer. In particular, the SQ02/BP-D4 dimer showed 10 times larger (0.53 |e-|) unidirectional CT than that of SQ02/BP-2 dimer, in addition to the maximum increased electron population of acceptor moieties upon photoexcitation.


Assuntos
Corantes , Energia Solar , Teoria da Densidade Funcional , Elétrons , Modelos Moleculares
15.
SAR QSAR Environ Res ; 32(10): 817-834, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34530657

RESUMO

Simplified molecular-input line-entry system (SMILES) notation and inbuilt Monte Carlo algorithm of CORAL software were employed to construct generative and prediction QSPR models for the analysis of the power conversion efficiency (PCE) of 215 phenothiazine derivatives. The dataset was divided into four splits and each split was further divided into four sets. A hybrid descriptor, a combination of SMILES and hydrogen suppressed graph (HSG), was employed to build reliable and robust QSPR models. The role of the index of ideality of correlation (IIC) was also studied in depth. We performed a comparative study to predict PCE using two target functions (TF1 without IIC and TF2 with IIC). Eight QSPR models were developed and the models developed with TF2 was shown robust and reliable. The QSPR model generated from split 4 was considered a leading model. The different statistical benchmarks were computed for the lead model and these were rtraining set2=0.7784; rinvisible training set2=0.7955; rcalibration set2=0.7738; rvalidation set2=0.7506; Qtraining set2=0.7691; Qinvisible training set2=0.7850; Qcalibration set2=0.7501;  Qvalidation set2=0.7085; IICtraining set = 0.8590; IICinvisible training set = 0.8297; IICcalibration set = 0.8796; IICvalidation set = 0.8293, etc. The promoters of increase and decrease of endpoint PCE were also extracted.


Assuntos
Corantes/química , Fenotiazinas/química , Energia Solar , Método de Monte Carlo , Relação Quantitativa Estrutura-Atividade
16.
PLoS One ; 16(9): e0256439, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34543300

RESUMO

The thermal environment of village public space affects the comfort of people ' s outdoor activities, and then affects the willingness of residents to outdoor activities, which has an important impact on the villagers' quality of life. Previously published studies of thermal comfort mostly focused on the evaluation of thermal comfort index, few studies on the application of thermal comfort planning. The study was carried out in Maling Village, Changdai Town, Mengjin County, Luoyang City, Henan Province, China. Square, street, green space were chosen as three typical public spaces where thermal comfort indexes were measured by questionnaire survey and field measurement during summer. Subsequently, the village's microclimate environment was simulated with ArcGIS 10.6 and ENVI-met. The results indicate that during the summer, the influences of temperature, solar radiation, wind speed, and relative humidity on the subjective comfort conditions of the outdoor environment gradually decreased. The spatial form of village has an important influence on thermal comfort. Finally, based on the results, this study put forward the thermal comfort process and planning scheme of the village outdoor space.


Assuntos
Microclima , Qualidade de Vida , Energia Solar , Sensação Térmica/fisiologia , China/epidemiologia , Cidades , Humanos , Umidade , Estações do Ano , Inquéritos e Questionários , Temperatura , Árvores , Vento
17.
J Phys Chem Lett ; 12(39): 9525-9530, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34559971

RESUMO

Triplet-triplet annihilation (TTA) upconversion has shown promising potentials in the augmentation of solar energy conversion. However, challenging issues exist in improving TTA upconversion efficiencies in solid-states, one of which is the back energy transfer from upconverted singlet annihilators to sensitizers, resulting in decreasing upconversion emission. Here we present a light-harvesting molecular wire consisting of dendrons with 9,10-diphenylanthracene derivatives (DPAEH) at the periphery and p-phenylene ethynylene oligomers (PPE) as the wire core. The peripheral DPAEH antenna funnels singlet excitonic energy to the wire on a 12 ps time scale. Incorporating the molecular wire into the TTA upconversion solid consisting of the DPAEH annihilator and the porphyrin sensitizer evidently improves the upconversion quantum yield from 1.5% to 2.7% upon 532 nm excitation by suppressing the back energy transfer from the singlet annihilator to the sensitizer. This finding offers a potential route to use a singlet energy light-harvesting architecture for enhancing TTA upconversion.


Assuntos
Energia Solar , Antracenos/química , Transferência de Energia , Porfirinas/química , Espectrometria de Fluorescência
18.
Sensors (Basel) ; 21(16)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34451090

RESUMO

Solar energy penetration has been on the rise worldwide during the past decade, attracting a growing interest in solar power forecasting over short time horizons. The increasing integration of these resources without accurate power forecasts hinders the grid operation and discourages the use of this renewable resource. To overcome this problem, Virtual Power Plants (VPPs) provide a solution to centralize the management of several installations to minimize the forecasting error. This paper introduces a method to efficiently produce intra-day accurate Photovoltaic (PV) power forecasts at different locations, by using free and available information. Prediction intervals, which are based on the Mean Absolute Error (MAE), account for the forecast uncertainty which provides additional information about the VPP node power generation. The performance of the forecasting strategy has been verified against the power generated by a real PV installation, and a set of ground-based meteorological stations in geographical proximity have been used to emulate a VPP. The forecasting approach is based on a Long Short-Term Memory (LSTM) network and shows similar errors to those obtained with other deep learning methods published in the literature, offering a MAE performance of 44.19 W/m2 under different lead times and launch times. By applying this technique to 8 VPP nodes, the global error is reduced by 12.37% in terms of the MAE, showing huge potential in this environment.


Assuntos
Redes Neurais de Computação , Energia Solar , Previsões , Centrais Elétricas , Luz Solar
19.
Environ Sci Pollut Res Int ; 28(39): 54383-54402, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34403060

RESUMO

Good-quality drinking water is an essential requirement for a healthy and sustainable future. In the current scenario, people living in remote areas of the world are deficient of potable water, especially in developing nations. Desalination technologies available today are energy intensive and aggravate carbon emissions as most energy requirements are fulfilled by using fossil fuels. Solar still is a simple and direct solar desalination device used for water distillation. The major problem associated with a solar still is its low productivity. The main aim of this review paper is to discuss various modifications in a solar still which resulted in productivity enhancement. Different parameters affecting a passive solar still performance and their optimum values for maximum productivity are also thoroughly analysed in this paper. Water depth is an important operating parameter that influences still productivity, and various results showed that maximum productivity is achieved mostly at minimum water depths.


Assuntos
Destilação , Água Potável , Energia Solar , Purificação da Água , Destilação/instrumentação , Destilação/métodos , Humanos , Purificação da Água/instrumentação , Purificação da Água/métodos
20.
Macromol Rapid Commun ; 42(17): e2100305, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34347333

RESUMO

Tandem solar cells which are electrically connected with various photoactive materials have the potential to solve the current challenges by exceeding the theoretically limited efficiency of single junction solar cells. Here the first monolithic organic/silicon tandem cell is reported based on a semitransparent polymer on a crystalline silicon (c-Si) substrate. Herein, experimental results are presented for four-terminal (4-T) and monolithic two-terminal (2-T) organic/c-Si tandem cells using organic cells with an inverted n-i-p structure and c-Si cells with an n-type TOPCon structure with detailed analysis. The best 4-T tandem cell efficiency is 15.22%, and 2-T results show that the top (organic) and bottom (c-Si) cells are electrically connected by an open-circuit voltage over 1.4 V. Further, a simulated efficiency of over 20% using the organic/c-Si tandem is achieved, implying the tandem efficiency can be enhanced through further improvement of electric and optical characteristics with the optimization.


Assuntos
Energia Solar , Eletrodos , Polímeros , Silício , Luz Solar
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