The development of lignocellulose-based adsorbents for the removal of heavy metals from wastewater has attracted **** recent attention. In this work, a high-yield cellulose bacterial strain Comamonas testosteroni FJ17 was evaluated for its capacity to modify rice straw towards increased Cu(II) removal. For optimum modification time (45.5 h), inoculum concentration (1.25%), and rice straw dose (12.6 g L-1) the optimized adsorption capacity was 28.4 mg g-1. After strain FJ17 modification the equilibrium adsorption percentage of rice straw for Cu(II) increased from 6.6 to 27.4% at an initial concentration of 100 mg L-1. This increase was attributed to an increase in rice straw surface modification, leading to improved adsorption ability. SEM-EDS indicated that, following strain FJ17 treatment, the surface of the rice straw became more disintegrated and the specific surface area consequentially increased from 1.9 to 3.7 m2 g-1. FTIR analysis also showed new functional groups (carbonyl) appearing, and CC and CH3CR functionality being enhanced after biomodification. Functional groups associated with the benzene ring, silicified polymer and carbohydrates were all involved in the adsorption process. Adsorption of Cu was well described by the Freundlich isotherm model (R2 > 0.98) where adsorption was endothermic with potential for both chemical and physical interactions to coexist. Reusability experiments showed that the removal efficiency of Cu(II) decreased from 96.9 to 73.2% after five cycles. Overall C.testosteroni-treated rice straw had significant potential as a heavy metal biosorbent.Organic matter plays many roles in the soil ecosystem. One property of the substance concerns the metal complexation and interaction with organic contaminants. In this sense, the humic substances (HS), a heterogeneous mixture of compounds, naturally derived from degradation of biomass, have been widely studied in environmental sciences. Recent advances showed a new way to produce humic-like substances (HLS) through hydrothermal carbonization of biomass. Thus, this study aimed to evaluate the HLS of hydrochars, produced by using a mixture of sugarcane bagasse and vinasse with sulfuric acid added (1 and 4% v/v), and to assess their interactions with metal ions, (Fe(III), Al(III), Cu(II) and Co(II)) using EEM-PARAFAC and a two-dimensional FTIR correlation analysis. The results were compared to the humic substances extracted from the Amazonian Anthrosol, as a model of anthropogenic organic matter. NMR analysis showed that humic-like extracts from hydrochar are mainly hydrophobic, while the soil has a greater contribution of polar moieties. The HLS and HS showed similar complexation capacities for Fe(III), Al(III) and Cu(II) assays. For Co(II) HLS exhibited larger affinities than HS. Two-dimensional correlation analysis FTIR showed that chemical groups may undergo conformational alteration with metal additions to achieve more stable arrangements (higher stability constant). Therefore, these results contribute more knowledge about the mechanism of HS and metal ion interaction, as well as showing that HTC can be an interesting option for HLS production, to be used as humic based materials.Aim We aimed to assess if snoring and ambient air pollutants were jointly associated with prevalent hypertension in a cross-sectional study. https://www.selleckchem.com/products/CP-690550.html Methods A total of 28440 participants aged 18-79 years were obtained from the Henan Rural Cohort. Snoring evaluated using Pittsburgh sleep quality index (PSQI) scale was classified into 'Never', ' less then 3 times/week' and '≥3 times/week' groups. Concentrations of air pollutants (PM1, PM2.5, PM10, and NO2) were evaluated by a satellite-based spatiotemporal model. The independent and joint associations between snoring and air pollutants on prevalence of hypertension were analyzed by logistic regression models. Results The mean age of all participants was 56.0 ± 12.2 years. The frequencies and prevalence of participants with hypertension were 3666 (32.39%) in men and 5576(32.57%) in women, respectively. The odds ratio (OR) and 95% confidence interval (CI) of participants with snoring frequency of less then 3 times/week, ≥3 times/week was 1.10(1.02-1.20), and 1.15(1.08-1.23) for hypertension, compared to those without snoring. Participants with a snoring (≥3 times/week) and higher exposure concentrations of PM1, PM2.5, PM10, and NO2 had 2.58-fold(95% CI 2.30-2.90), 3.03-fold(95% CI 2.69-3.41), 2.89-fold(95% CI 2.57-3.25) and 2.75-fold(95% CI 2.44-3.10) for hypertension, compared to those without snoring and low concentrations of air pollutants. Additionally, participants with high PM1 and ≥3 times/week snoring (OR 1.32, 95% CI 1.18-1.48) was at a higher likelihood for prevalent hypertension, compared to those without snoring and with high PM1. Conclusions Snoring and high ambient air pollutants might be important predictors of hypertension, and higher concentration of PM1 might aggravate the association between snoring and hypertension.Catalytic reduction of toxic and aqueous stable nitrophenols by gold nanoparticles (Au NPs) is hot issue due to the serious environmental pollution in recent years. But the expensive price and poor recycling performance of Au NPs limit its further application. Defect-free high silica zeolite is suitable support for Au NPs due to its cheaper price, higher stability and stronger adsorbability, but the low alumina content and defect sites usually lead to poor Au NPs loading efficiency. Herein, we reported the improved Au NPs loading efficiency on defect-free high silica ZSM-5 zeolite through the additional surface fluffy structure. The fluffy structure was created through the addition of multi-walled carbon nanotubes (MWCNTs) and ethanol into synthesis gel. Highly dispersed ca. 4 nm Au NPs on zeolite surface are prepared by the green enhanced sol-gel immobilization method. The Au NPs loading efficiency on conventional ZSM-5 zeolite is 10.7%, in contrast, this result can arrive to 82.6% on fluffy structure ZSM-5 zeolite. The fluffy structure ZSM-5 zeolite and Au NPs nanocomposites show higher efficiency than traditional Au/ZSM-5 nanocomposites towards catalytic reduction of nitrophenols. Additionally, the experiments with different affecting factors (MWCNTs dosage, aging time, catalysts dosage, pH, initial 4-NP concentration, storage time and recycling times) were carried out to test general applicability of the nanocomposites. And the degradation of nitrophenols experiment was operated to explore the catalytic performance of the prepared nanocomposites in further environmental application. The detailed possible relationship between zeolite with fluffy structure and Au NPs is also proposed in the paper.
The development of lignocellulose-based adsorbents for the removal of heavy metals from wastewater has attracted much recent attention. In this work, a high-yield cellulose bacterial strain Comamonas testosteroni FJ17 was evaluated for its capacity to modify rice straw towards increased Cu(II) removal. For optimum modification time (45.5 h), inoculum concentration (1.25%), and rice straw dose (12.6 g L-1) the optimized adsorption capacity was 28.4 mg g-1. After strain FJ17 modification the equilibrium adsorption percentage of rice straw for Cu(II) increased from 6.6 to 27.4% at an initial concentration of 100 mg L-1. This increase was attributed to an increase in rice straw surface modification, leading to improved adsorption ability. SEM-EDS indicated that, following strain FJ17 treatment, the surface of the rice straw became more disintegrated and the specific surface area consequentially increased from 1.9 to 3.7 m2 g-1. FTIR analysis also showed new functional groups (carbonyl) appearing, and CC and CH3CR functionality being enhanced after biomodification. Functional groups associated with the benzene ring, silicified polymer and carbohydrates were all involved in the adsorption process. Adsorption of Cu was well described by the Freundlich isotherm model (R2 > 0.98) where adsorption was endothermic with potential for both chemical and physical interactions to coexist. Reusability experiments showed that the removal efficiency of Cu(II) decreased from 96.9 to 73.2% after five cycles. Overall C.testosteroni-treated rice straw had significant potential as a heavy metal biosorbent.Organic matter plays many roles in the soil ecosystem. One property of the substance concerns the metal complexation and interaction with organic contaminants. In this sense, the humic substances (HS), a heterogeneous mixture of compounds, naturally derived from degradation of biomass, have been widely studied in environmental sciences. Recent advances showed a new way to produce humic-like substances (HLS) through hydrothermal carbonization of biomass. Thus, this study aimed to evaluate the HLS of hydrochars, produced by using a mixture of sugarcane bagasse and vinasse with sulfuric acid added (1 and 4% v/v), and to assess their interactions with metal ions, (Fe(III), Al(III), Cu(II) and Co(II)) using EEM-PARAFAC and a two-dimensional FTIR correlation analysis. The results were compared to the humic substances extracted from the Amazonian Anthrosol, as a model of anthropogenic organic matter. NMR analysis showed that humic-like extracts from hydrochar are mainly hydrophobic, while the soil has a greater contribution of polar moieties. The HLS and HS showed similar complexation capacities for Fe(III), Al(III) and Cu(II) assays. For Co(II) HLS exhibited larger affinities than HS. Two-dimensional correlation analysis FTIR showed that chemical groups may undergo conformational alteration with metal additions to achieve more stable arrangements (higher stability constant). Therefore, these results contribute more knowledge about the mechanism of HS and metal ion interaction, as well as showing that HTC can be an interesting option for HLS production, to be used as humic based materials.Aim We aimed to assess if snoring and ambient air pollutants were jointly associated with prevalent hypertension in a cross-sectional study. https://www.selleckchem.com/products/CP-690550.html Methods A total of 28440 participants aged 18-79 years were obtained from the Henan Rural Cohort. Snoring evaluated using Pittsburgh sleep quality index (PSQI) scale was classified into 'Never', ' less then 3 times/week' and '≥3 times/week' groups. Concentrations of air pollutants (PM1, PM2.5, PM10, and NO2) were evaluated by a satellite-based spatiotemporal model. The independent and joint associations between snoring and air pollutants on prevalence of hypertension were analyzed by logistic regression models. Results The mean age of all participants was 56.0 ± 12.2 years. The frequencies and prevalence of participants with hypertension were 3666 (32.39%) in men and 5576(32.57%) in women, respectively. The odds ratio (OR) and 95% confidence interval (CI) of participants with snoring frequency of less then 3 times/week, ≥3 times/week was 1.10(1.02-1.20), and 1.15(1.08-1.23) for hypertension, compared to those without snoring. Participants with a snoring (≥3 times/week) and higher exposure concentrations of PM1, PM2.5, PM10, and NO2 had 2.58-fold(95% CI 2.30-2.90), 3.03-fold(95% CI 2.69-3.41), 2.89-fold(95% CI 2.57-3.25) and 2.75-fold(95% CI 2.44-3.10) for hypertension, compared to those without snoring and low concentrations of air pollutants. Additionally, participants with high PM1 and ≥3 times/week snoring (OR 1.32, 95% CI 1.18-1.48) was at a higher likelihood for prevalent hypertension, compared to those without snoring and with high PM1. Conclusions Snoring and high ambient air pollutants might be important predictors of hypertension, and higher concentration of PM1 might aggravate the association between snoring and hypertension.Catalytic reduction of toxic and aqueous stable nitrophenols by gold nanoparticles (Au NPs) is hot issue due to the serious environmental pollution in recent years. But the expensive price and poor recycling performance of Au NPs limit its further application. Defect-free high silica zeolite is suitable support for Au NPs due to its cheaper price, higher stability and stronger adsorbability, but the low alumina content and defect sites usually lead to poor Au NPs loading efficiency. Herein, we reported the improved Au NPs loading efficiency on defect-free high silica ZSM-5 zeolite through the additional surface fluffy structure. The fluffy structure was created through the addition of multi-walled carbon nanotubes (MWCNTs) and ethanol into synthesis gel. Highly dispersed ca. 4 nm Au NPs on zeolite surface are prepared by the green enhanced sol-gel immobilization method. The Au NPs loading efficiency on conventional ZSM-5 zeolite is 10.7%, in contrast, this result can arrive to 82.6% on fluffy structure ZSM-5 zeolite. The fluffy structure ZSM-5 zeolite and Au NPs nanocomposites show higher efficiency than traditional Au/ZSM-5 nanocomposites towards catalytic reduction of nitrophenols. Additionally, the experiments with different affecting factors (MWCNTs dosage, aging time, catalysts dosage, pH, initial 4-NP concentration, storage time and recycling times) were carried out to test general applicability of the nanocomposites. And the degradation of nitrophenols experiment was operated to explore the catalytic performance of the prepared nanocomposites in further environmental application. The detailed possible relationship between zeolite with fluffy structure and Au NPs is also proposed in the paper.
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