cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.20078857.v1
title: The Fate of Atrazine in Tropical Environments: Photolysis, Acute Toxicity and Endocrine Disruptor Potential

description: Triazine herbicides are widely used both in Brazil and internationally and are frequently detected in natural environments and drinking water. This study assesses atrazine degradation through solar radiation under tropical conditions and determines the toxicity of the intermediates. Atrazine degradation is tested through ultrapure water, humic acid solution and natural water experiments, with exposure to sunlight to simulate a natural environment. A yeast estrogen screen (YES) assay and Artemia salina test are carried out during the abiotic degradation. The atrazine degradation depends on the radiation intensity, since the experiments conducted in the summer reached 50% after ca. 17 days. No significant variations in this herbicide concentration are observed after 90 days of exposure in the fall. Atrazine degradation is observed only in humic acid and is responsible for indirect photolysis. Intermediates, namely, desethylatrazine (DEA) and deisopropylatrazine (DIA), are identified and quantified at the μg L-1 level. Thus, with the degradation of atrazine in water, the medium toxicity may decrease, since DEA and DIA have mean effective concentrations that kill 50% of Artemia salina (EC50) similars to atrazine (13 mg L-1). No estrogenic activity in the YES is detected for atrazine and its metabolites. These findings evidence that radiation intensity and organic substances in tropical countries influence the half-life of pesticides in aquatic environments.
DOI: 10.6084/m9.figshare.20078857
title: The Fate of Atrazine in Tropical Environments: Photolysis, Acute Toxicity and Endocrine Disruptor Potential

description: Triazine herbicides are widely used both in Brazil and internationally and are frequently detected in natural environments and drinking water. This study assesses atrazine degradation through solar radiation under tropical conditions and determines the toxicity of the intermediates. Atrazine degradation is tested through ultrapure water, humic acid solution and natural water experiments, with exposure to sunlight to simulate a natural environment. A yeast estrogen screen (YES) assay and Artemia salina test are carried out during the abiotic degradation. The atrazine degradation depends on the radiation intensity, since the experiments conducted in the summer reached 50% after ca. 17 days. No significant variations in this herbicide concentration are observed after 90 days of exposure in the fall. Atrazine degradation is observed only in humic acid and is responsible for indirect photolysis. Intermediates, namely, desethylatrazine (DEA) and deisopropylatrazine (DIA), are identified and quantified at the μg L-1 level. Thus, with the degradation of atrazine in water, the medium toxicity may decrease, since DEA and DIA have mean effective concentrations that kill 50% of Artemia salina (EC50) similars to atrazine (13 mg L-1). No estrogenic activity in the YES is detected for atrazine and its metabolites. These findings evidence that radiation intensity and organic substances in tropical countries influence the half-life of pesticides in aquatic environments.
DOI: 10.6084/m9.figshare.20078875
title: Addition of N-(2-Aminoethyl)naphthalimide and Mercaptopropionic Acid to Increase the Stability of CsFAMA Perovskite Solar Cells

description: Sustainable energy generation has been a growing concern worldwide due to the alarming effects of climate changes in the last few decades. In this scenario, perovskite solar cells hold great promise in contributing for a greener global energy matrix. Despite the great potential of this technology, several difficulties to deploy perovskite solar panels are yet to be overcome, being their long-term stability one of the most critical. In this sense, this work offers an alternative to improve the long-term, operational stability of the devices by passivating the CsFAMA perovskite active layer with a mixture of N-(2-aminoethyl)naphthalimide and mercaptopropionic acid. These modifications improved the perovskite and device stability under ambient conditions. The solar cells without encapsulation and with post-treatment with 5 mM modifier solution retained ca. 90% of its initial power conversion efficiency (PCE) after 500 h exposed to ambient conditions, while standard solar cells retained ca. 58%. Our approach offers a simple new method to improve the stability of perovskite solar cells using an unexplored combination of passivating molecules.
DOI: 10.6084/m9.figshare.20078875.v1
title: Addition of N-(2-Aminoethyl)naphthalimide and Mercaptopropionic Acid to Increase the Stability of CsFAMA Perovskite Solar Cells

description: Sustainable energy generation has been a growing concern worldwide due to the alarming effects of climate changes in the last few decades. In this scenario, perovskite solar cells hold great promise in contributing for a greener global energy matrix. Despite the great potential of this technology, several difficulties to deploy perovskite solar panels are yet to be overcome, being their long-term stability one of the most critical. In this sense, this work offers an alternative to improve the long-term, operational stability of the devices by passivating the CsFAMA perovskite active layer with a mixture of N-(2-aminoethyl)naphthalimide and mercaptopropionic acid. These modifications improved the perovskite and device stability under ambient conditions. The solar cells without encapsulation and with post-treatment with 5 mM modifier solution retained ca. 90% of its initial power conversion efficiency (PCE) after 500 h exposed to ambient conditions, while standard solar cells retained ca. 58%. Our approach offers a simple new method to improve the stability of perovskite solar cells using an unexplored combination of passivating molecules.
DOI: 10.6084/m9.figshare.20078876
title: Trends in Carbon Dioxide Capture and Conversion

description: Carbon dioxide capture and conversion is gaining increased attention due to climate change issues. The direct air capture of CO2 may be accomplished with functionalized adsorbents that can work at atmospheric pressure and room temperature. The captured CO2 may be converted into fuels and chemicals. CO2 can be hydrogenated to methanol, which is a commodity used in the fuel and chemical sectors, over Cu.ZnO-based catalysts. Improvements to catalyst formulation are still needed to operate at lower temperatures. Dimethyl ether can be directly produced from CO2 and H2 through the use of bifunctional catalysts. Organic carbonates appear as promising compounds of wide use in the chemical sector. Cyclic carbonates may be produced from CO2 and epoxides with the use of Lewis acids catalyst. Zeolites impregnated with metal halides appear to be a promising system to achieve high conversion and selectivity. Aliphatic organic carbonates can be produced from CO2 and alcohols, but the reaction presents thermodynamic limitations. The role of oxygen vacancies on CeO2-based catalysts and use of dehydrating agents in the production of dimethyl carbonate will be discussed in this account. The challenges and future perspectives for the direct air CO2 capture and conversion into fuels and chemicals will be addressed.
DOI: 10.6084/m9.figshare.20078876.v1
title: Trends in Carbon Dioxide Capture and Conversion

description: Carbon dioxide capture and conversion is gaining increased attention due to climate change issues. The direct air capture of CO2 may be accomplished with functionalized adsorbents that can work at atmospheric pressure and room temperature. The captured CO2 may be converted into fuels and chemicals. CO2 can be hydrogenated to methanol, which is a commodity used in the fuel and chemical sectors, over Cu.ZnO-based catalysts. Improvements to catalyst formulation are still needed to operate at lower temperatures. Dimethyl ether can be directly produced from CO2 and H2 through the use of bifunctional catalysts. Organic carbonates appear as promising compounds of wide use in the chemical sector. Cyclic carbonates may be produced from CO2 and epoxides with the use of Lewis acids catalyst. Zeolites impregnated with metal halides appear to be a promising system to achieve high conversion and selectivity. Aliphatic organic carbonates can be produced from CO2 and alcohols, but the reaction presents thermodynamic limitations. The role of oxygen vacancies on CeO2-based catalysts and use of dehydrating agents in the production of dimethyl carbonate will be discussed in this account. The challenges and future perspectives for the direct air CO2 capture and conversion into fuels and chemicals will be addressed.
DOI: 10.6084/m9.figshare.20078879
title: Environmental factors on seasonal germination of different weedy rice(Oryza sativa L.) biotypes

description: ABSTRACT: Weedy biotypes of Oryza sativa L., (weedy rice) are a serious threat to rice production because of their flexibility in seed germination timing, variable growth forms, and high genetic diversity. Experiments were designed to determine the effects of storage conditions, osmotic stress, pH, salt stress, and burial depth on germination of weedy rice seeds in flooded or non-flooded conditions. Mature weedy rice seeds were gathered from rice fields in the different regions of Turkey. Three biotypes were selected and classified according to awn length; long awn, short awn and awnless. Seasonal germination patterns of weedy rice seeds in the laboratory after retrieval from various depths and timing were affected by burial depth, water regime, and exhumation timing across the treatments for all biotypes. The long and short awn biotypes had higher germination rates than the awnless biotype and did not have a seasonal germination pattern. Seed germination was initiated in the spring, peaked in summer and declined in the fall in flooded and non-flooded treatments for the awnless biotype. The most distinct differences in seedling emergence patterns were observed in awnless and long awn biotypes, and they emerged from 10 cm depth. Our results suggested that flooded conditions reduced the germination of weedy rice biotypes. Flooding rice paddies for a period of time after harvest may improve weedy rice control and decrease the weed population. In addition to deeper cultivation would be more effective in controlling all weedy biotypes since the majority of weed seedling emergence was from shallow depths.
DOI: 10.6084/m9.figshare.20078879.v1
title: Environmental factors on seasonal germination of different weedy rice(Oryza sativa L.) biotypes

description: ABSTRACT: Weedy biotypes of Oryza sativa L., (weedy rice) are a serious threat to rice production because of their flexibility in seed germination timing, variable growth forms, and high genetic diversity. Experiments were designed to determine the effects of storage conditions, osmotic stress, pH, salt stress, and burial depth on germination of weedy rice seeds in flooded or non-flooded conditions. Mature weedy rice seeds were gathered from rice fields in the different regions of Turkey. Three biotypes were selected and classified according to awn length; long awn, short awn and awnless. Seasonal germination patterns of weedy rice seeds in the laboratory after retrieval from various depths and timing were affected by burial depth, water regime, and exhumation timing across the treatments for all biotypes. The long and short awn biotypes had higher germination rates than the awnless biotype and did not have a seasonal germination pattern. Seed germination was initiated in the spring, peaked in summer and declined in the fall in flooded and non-flooded treatments for the awnless biotype. The most distinct differences in seedling emergence patterns were observed in awnless and long awn biotypes, and they emerged from 10 cm depth. Our results suggested that flooded conditions reduced the germination of weedy rice biotypes. Flooding rice paddies for a period of time after harvest may improve weedy rice control and decrease the weed population. In addition to deeper cultivation would be more effective in controlling all weedy biotypes since the majority of weed seedling emergence was from shallow depths.
DOI: 10.6084/m9.figshare.20078881
title: Vortex-Assisted Ionic Liquid-Based Liquid-Phase Microextraction: A Simple, Low Cost, and Environmentally Friendly Method for Speciation of Antimony in Water

description: A sensitive method is proposed to determine antimony species using vortex-assisted ionic liquid-based liquid-phase microextraction and digital imaging colorimetry. SbIII forms a ternary complex with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)phenol, ascorbic acid, and iodide in an acid medium. The acceptor phase consists of the ionic liquid 1-butyl-3-methylimidazole hexafluorophosphate, dispersed in the aqueous solution with a vortex stirrer. After centrifugation, SbIII was determined directly in the rich phase. SbV can also be measured by converting to reduced species. The method presented a limit of detection of 1.4 and 4.2 μg L-1 and an enrichment factor of 360. The precision (relative standard deviation) of the method is 7.0%. The procedure was applied to the speciation of antimony in river water and mineral water samples. Some results were compared with those obtained by electrothermal atomic absorption spectrometry (ET AAS). The method is an attractive alternative for determining antimony species, considering the aspects of green analytical chemistry.
DOI: 10.6084/m9.figshare.20078881.v1
title: Vortex-Assisted Ionic Liquid-Based Liquid-Phase Microextraction: A Simple, Low Cost, and Environmentally Friendly Method for Speciation of Antimony in Water

description: A sensitive method is proposed to determine antimony species using vortex-assisted ionic liquid-based liquid-phase microextraction and digital imaging colorimetry. SbIII forms a ternary complex with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)phenol, ascorbic acid, and iodide in an acid medium. The acceptor phase consists of the ionic liquid 1-butyl-3-methylimidazole hexafluorophosphate, dispersed in the aqueous solution with a vortex stirrer. After centrifugation, SbIII was determined directly in the rich phase. SbV can also be measured by converting to reduced species. The method presented a limit of detection of 1.4 and 4.2 μg L-1 and an enrichment factor of 360. The precision (relative standard deviation) of the method is 7.0%. The procedure was applied to the speciation of antimony in river water and mineral water samples. Some results were compared with those obtained by electrothermal atomic absorption spectrometry (ET AAS). The method is an attractive alternative for determining antimony species, considering the aspects of green analytical chemistry.
DOI: 10.6084/m9.figshare.20078885
title: Ultrasound Assisted Pretreatments Applied to Cupuaçu Husk (Theobroma grandiflorum) from Brazilian Legal Amazon for Biorefinery Concept

description: Cupuaçu husk (CH) is the waste of a common fruit from a native species of the Brazilian Legal Amazon. The current study investigated the influence of ultrasound (US) combined with aqueous, acid, alkaline, and ionic liquid (IL) pretreatments on the chemical and physical aspects of CH and the yield of chemical platforms production, 5-hydroxymethylfurfural (HMF) and furfural (FF), using IL. Scanning electron microscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy were used to feature the raw and pretreated biomass. The highest levels of glucose (9.90 g L-1) were observed in the liquid fraction resulting from the acid + US pretreatment followed by acid hydrolysis. The IL + US pretreatment recorded the best performance in removing lignin. Based on XRD analyses, ultrasound increased crystallinity of all pretreated samples as a result of the removal of cellulose’s amorphous fraction. However, it promoted accessibility to adopted reagents by increasing biomass exposure due to cavitation. The best yields of HMF and FF were recorded from hydrolysis of the solid fraction resulting from the acid + US (12.94%) and alkaline + US (48.84%) pretreatment, respectively. These results indicate satisfactory performance of ultrasound assisted pretreatments to the simplified and economic conversion of biomass into value-added products.
DOI: 10.6084/m9.figshare.20078885.v1
title: Ultrasound Assisted Pretreatments Applied to Cupuaçu Husk (Theobroma grandiflorum) from Brazilian Legal Amazon for Biorefinery Concept

description: Cupuaçu husk (CH) is the waste of a common fruit from a native species of the Brazilian Legal Amazon. The current study investigated the influence of ultrasound (US) combined with aqueous, acid, alkaline, and ionic liquid (IL) pretreatments on the chemical and physical aspects of CH and the yield of chemical platforms production, 5-hydroxymethylfurfural (HMF) and furfural (FF), using IL. Scanning electron microscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy were used to feature the raw and pretreated biomass. The highest levels of glucose (9.90 g L-1) were observed in the liquid fraction resulting from the acid + US pretreatment followed by acid hydrolysis. The IL + US pretreatment recorded the best performance in removing lignin. Based on XRD analyses, ultrasound increased crystallinity of all pretreated samples as a result of the removal of cellulose’s amorphous fraction. However, it promoted accessibility to adopted reagents by increasing biomass exposure due to cavitation. The best yields of HMF and FF were recorded from hydrolysis of the solid fraction resulting from the acid + US (12.94%) and alkaline + US (48.84%) pretreatment, respectively. These results indicate satisfactory performance of ultrasound assisted pretreatments to the simplified and economic conversion of biomass into value-added products.
DOI: 10.6084/m9.figshare.20078888
title: Description of the peach fruit growth curve by diphasic sigmoidal nonlinear models

description: Abstract The aim of this study was to describe the growth curve of “Aurora 1” peaches using fruit height and diameter data over time through diphasic sigmoidal models constructed from eight combinations of the following models: Brody, Gompertz and Logistic. Data were obtained from an experiment carried out in 2005 in the municipality of Vista Alegre do Alto, São Paulo, Brazil. The parameters of models were adjusted by the least squares method using the Gauss-Newton algorithm implemented in the R software. Assumptions of normality, homogeneity and independence of residues were verified based on Shapiro-Wilk, Breush and Pagan and Durbin-Watson tests, respectively. The goodness of fit of models was verified according to the corrected Akaike information criterion (AICc), residual standard deviation (RSD), asymptote adjustment index (AI) and nonlinearity measures. All models adjusted for both fruit height and diameter variables met the assumptions of normality, independence and homoscedasticity of errors. In addition, all of them present good quality of fit to fruit height and diameter data, since they presented AI values close to one and low RSD values and non-linearity measures. However, the double Gompertz (GG) and the Logistic + Gompertz (LG) models presented, respectively, the best quality of fit to fruit height and diameter data in relation to the other models. It could be concluded that all diphasic sigmoidal models evaluated showed good fit to height and diameter data and can be used to describe the growth curve of “Aurora-1” peaches, according to goodness of fit criteria. However, it is important to highlight that GG and LG models presented the best quality of fit and can be selected to describe the height and diameter growth of “Aurora 1” peach fruits, respectively, with maximum expected growth close to 63 mm in height and 48 mm in diameter.
DOI: 10.6084/m9.figshare.20078888.v1
title: Description of the peach fruit growth curve by diphasic sigmoidal nonlinear models

description: Abstract The aim of this study was to describe the growth curve of “Aurora 1” peaches using fruit height and diameter data over time through diphasic sigmoidal models constructed from eight combinations of the following models: Brody, Gompertz and Logistic. Data were obtained from an experiment carried out in 2005 in the municipality of Vista Alegre do Alto, São Paulo, Brazil. The parameters of models were adjusted by the least squares method using the Gauss-Newton algorithm implemented in the R software. Assumptions of normality, homogeneity and independence of residues were verified based on Shapiro-Wilk, Breush and Pagan and Durbin-Watson tests, respectively. The goodness of fit of models was verified according to the corrected Akaike information criterion (AICc), residual standard deviation (RSD), asymptote adjustment index (AI) and nonlinearity measures. All models adjusted for both fruit height and diameter variables met the assumptions of normality, independence and homoscedasticity of errors. In addition, all of them present good quality of fit to fruit height and diameter data, since they presented AI values close to one and low RSD values and non-linearity measures. However, the double Gompertz (GG) and the Logistic + Gompertz (LG) models presented, respectively, the best quality of fit to fruit height and diameter data in relation to the other models. It could be concluded that all diphasic sigmoidal models evaluated showed good fit to height and diameter data and can be used to describe the growth curve of “Aurora-1” peaches, according to goodness of fit criteria. However, it is important to highlight that GG and LG models presented the best quality of fit and can be selected to describe the height and diameter growth of “Aurora 1” peach fruits, respectively, with maximum expected growth close to 63 mm in height and 48 mm in diameter.
DOI: 10.6084/m9.figshare.20078890.v1
title: Iron Recovery from Iron Ore Tailings by Direct Hydrogen Reduction at Low Temperature and Magnetic Separation

description: In this work, we describe a sustainable alternative to recover iron from two iron ore tailings (IOT) using hydrogen reduction at relatively low temperatures followed by magnetic separation. X-ray powder diffraction (XRD), inductively coupled plasma (ICP), atomic absorption (AA), Mössbauer, scanning electron microscopy (SEM/EDS), Raman and thermogravimetry (TG) analyses indicated that the Fe oxide present in the IOTs (sandy tailing (ST) and mud tailings (MT)), can be reduced with H2 at 500 ºC to produce α-Fe. Upon magnetic separation the mud tailing produced a 77 wt.% magnetic fraction increasing the Fe content from 19.2 to ca. 56 wt.% of Fe. On the other hand, the sandy tailing resulted in a 15 wt.% magnetic fraction increasing the Fe content from 19.2 to 70 wt.%. These results indicate that up to 86% of iron can be recovered from the IOT wastes already in the metallic form which can be very interesting for the steel industry.
DOI: 10.6084/m9.figshare.20078890
title: Iron Recovery from Iron Ore Tailings by Direct Hydrogen Reduction at Low Temperature and Magnetic Separation

description: In this work, we describe a sustainable alternative to recover iron from two iron ore tailings (IOT) using hydrogen reduction at relatively low temperatures followed by magnetic separation. X-ray powder diffraction (XRD), inductively coupled plasma (ICP), atomic absorption (AA), Mössbauer, scanning electron microscopy (SEM/EDS), Raman and thermogravimetry (TG) analyses indicated that the Fe oxide present in the IOTs (sandy tailing (ST) and mud tailings (MT)), can be reduced with H2 at 500 ºC to produce α-Fe. Upon magnetic separation the mud tailing produced a 77 wt.% magnetic fraction increasing the Fe content from 19.2 to ca. 56 wt.% of Fe. On the other hand, the sandy tailing resulted in a 15 wt.% magnetic fraction increasing the Fe content from 19.2 to 70 wt.%. These results indicate that up to 86% of iron can be recovered from the IOT wastes already in the metallic form which can be very interesting for the steel industry.