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1.
Environ Sci Technol ; 58(40): 17766-17776, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39315852

RESUMO

Pyrogenic carbon is considered an enhancer to H2-yielding dark fermentation (DF), but little is known about how it regulates extracellular electron transfer (EET) and influences transmembrane respiratory chains and intracellular metabolisms. This study addressed these knowledge gaps and demonstrated that wood waste pyrogenic carbon (biochar) could significantly improve the DF performance; e.g., addition of pyrogenic carbon produced by pyrolysis at 800 °C (PC800) increased H2 yield by 369.7%. Biochemical quantification, electrochemical analysis, and electron respiratory chain inhibition tests revealed that PC800 promoted the extracellular flavin-based electron transfer process and further activated the acceleration of the transmembrane electron transfer. Comparative metagenome/metatranscriptome analyses indicated that the flavin-containing Rnf complex was the potential transmembrane respiratory enzyme associated with PC800-mediated EET. Based on NADH/NAD+ circulation, the promoted Rnf complex could stimulate the functions of the electron bifurcating Etf/Bcd complex and startup of glycolysis. The promoted Etf/Bcd could further contribute to balance the NADH/NAD+ level for glycolytic reactions and meanwhile provide reduced ferredoxin for group A1 [FeFe]-hydrogenases. This proton-energy-linked mechanism could achieve coupling production of ATP and H2. This study verified the important roles of pyrogenic carbon in mediating EET and transmembrane/intracellular pathways and revealed the crucial roles of electron bifurcation in DF for hydrogen production.


Assuntos
Fermentação , Hidrogênio , Transporte de Elétrons , Hidrogênio/metabolismo , Carbono/metabolismo , Flavinas/metabolismo , Elétrons
2.
Environ Sci Technol ; 58(27): 12123-12134, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38934384

RESUMO

Clay minerals are ubiquitous in subsurface environments and have long been recognized as having a limited or negligible impact on the fate of arsenic (As) due to their negatively charged surfaces. Here, we demonstrate the significant role of kaolinite (Kln), a pervasive clay mineral, in enhancing As(V) immobilization during ferrous iron (Fe(II)) oxidation at near-neutral pH. Our results showed that Fe(II) oxidation alone was not capable of immobilizing As(V) at relatively low Fe/As molar ratios (≤2) due to the generation of Fe(III)-As(V) nanocolloids that could still migrate easily as truly dissolved As did. In the presence of kaolinite, dissolved As(V) was significantly immobilized on the kaolinite surfaces via forming Kln-Fe(III)-As(V) ternary precipitates, which had large sizes (at micrometer levels) to reduce the As mobility. The kaolinite-induced heterogeneous pathways for As(V) immobilization involved Fe(II) adsorption, heterogeneous oxidation of adsorbed Fe(II), and finally heterogeneous nucleation/precipitation of Fe(III)-As(V) phases on the edge surfaces of kaolinite. The surface precipitates were mixtures of amorphous basic Fe(III)-arsenate and As-rich hydrous ferric oxide. Our findings provide new insights into the role of clay minerals in As transformation, which is significant for the fate of As in natural and engineered systems.


Assuntos
Arseniatos , Caulim , Oxirredução , Caulim/química , Arseniatos/química , Ferro/química , Compostos Ferrosos/química , Adsorção
3.
Environ Res ; 245: 118026, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38151144

RESUMO

In the context of the circular economy, the development of innovative and low-carbon concrete that incorporates different kinds of waste materials is gaining attention among the research community, regulatory agencies, and policymakers. These materials can be incorporated into concrete mixtures as aggregates or as fillers for improvement of product properties. This study aims to identify reliable designs for biochar-augmented cementitious products and general applications through technical, environmental, and economic assessments. The outcomes demonstrate that 5 wt% biochar addition could enhance the compressive strength of the final products. Using biochar, together with other recycled materials, can enormously reduce the environmental impacts, especially for global warming, enabling biochar-augmented cementitious products and general application as carbon-negative resources. The highest GWP reduction reached -720 kg CO2/tonne, equal to a 200% saving. A high quantity of biochar could be included in several specific applications (up to 60 wt%). The economic assessment highlights that the proposed designs are cost-effective and carbon tax can be significantly reduced. Carbon credits can also be earned for some carbon-negative designs. These findings can serve to mitigate GHG emissions and provide decision-makers with a reliable and holistic framework towards the goal of carbon neutrality.


Assuntos
Carbono , Carvão Vegetal , Análise Custo-Benefício , Aquecimento Global
4.
J Hum Nutr Diet ; 37(4): 943-951, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38664922

RESUMO

BACKGROUND: Many young adults report poor diet quality. However, research evaluating whether young adult males and females differ in diet quality is limited. Additionally, although diet quality has a known inverse association with body mass index (BMI), it is unclear whether this association is observed in young adults and whether it varies by gender. The present study aimed to evaluate gender differences in diet quality in young adults, as well as the associations between diet quality and BMI. METHODS: Data collected via the Healthy Eating Quiz (HEQ) in respondents aged 18-35 years between July 2019 and December 2021 were analysed, including demographics, and diet quality calculated using the Australian Recommended Food Score (ARFS). Differences in characteristics were analysed using a two-sample t-test, chi-squared and one-way analysis of covariance. Linear regressions were performed to estimate associations between diet quality and BMI. An interaction term was included in the model to test differences between genders. RESULTS: The respondents (n = 28,969) were predominantly female (70.8%) with a mean ± SD age of 25.9 ± 5.0 years and BMI of 24.6 ± 5.2 kg/m2. The mean ± SD ARFS was significantly different between females and males (33.1 ± 8.6 vs. 31.4 ± 9.3 points out of 70; p < 0.001). Diet quality had a small, significant inverse association with BMI in both genders. The interaction effect between diet quality score and gender in predicting BMI was significant (p < 0.001), suggesting the impact of diet quality on BMI varies by gender, with lower diet quality more strongly associated with higher BMI in females compared to males. CONCLUSION: Interventions that target young adults are needed to improve diet quality and its potential contribution to BMI status. As a result of the small observed effect sizes, caution should be applied in interpreting these findings.


Assuntos
Índice de Massa Corporal , Dieta Saudável , Humanos , Masculino , Feminino , Adulto , Austrália , Adulto Jovem , Dieta Saudável/estatística & dados numéricos , Fatores Sexuais , Adolescente , Dieta/estatística & dados numéricos , Dieta/métodos , Inquéritos sobre Dietas
5.
Environ Sci Technol ; 57(9): 3940-3950, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36800282

RESUMO

Selective and highly efficient extraction technologies for the recovery of critical metals including lithium, nickel, cobalt, and manganese from spent lithium-ion battery (LIB) cathode materials are essential in driving circularity. The tailored deep eutectic solvent (DES) choline chloride-formic acid (ChCl-FA) demonstrated a high selectivity and efficiency in extracting critical metals from mixed cathode materials (LiFePO4:Li(NiCoMn)1/3O2 mass ratio of 1:1) under mild conditions (80 °C, 120 min) with a solid-liquid mass ratio of 1:200. The leaching performance of critical metals could be further enhanced by mechanochemical processing because of particle size reduction, grain refinement, and internal energy storage. Furthermore, mechanochemical reactions effectively inhibited undesirable leaching of nontarget elements (iron and phosphorus), thus promoting the selectivity and leaching efficiency of critical metals. This was achieved through the preoxidation of Fe and the enhanced stability of iron phosphate framework, which significantly increased the separation factor of critical metals to nontarget elements from 56.9 to 1475. The proposed combination of ChCl-FA extraction and the mechanochemical reaction can achieve a highly selective extraction of critical metals from multisource spent LIBs under mild conditions.


Assuntos
Lítio , Reciclagem , Metais , Cobalto , Fontes de Energia Elétrica , Ferro
6.
J Environ Manage ; 339: 117938, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37080097

RESUMO

Low-carbon and high-efficiency binder is desirable for sustainable treatment of municipal solid waste incineration fly ash (MSWI FA). In this study, CaO or MgO was used to activate ground granulated blast furnace slag (GGBS) to form calcium silicate hydrate and magnesium silica hydrate gel for stabilization/solidification of hazardous MSWI FA. Experimental results showed that potential toxic elements (PTEs), such as Pb and Zn, significantly inhibited the formation of reaction products in CaO-GGBS system due to the complexation between Ca(OH)2 and PTEs, whereas PTEs only had insignificant inhibition on transformation from MgO to Mg(OH)2 in MgO-GGBS system, resulting in lower leachabilities of PTEs and higher mechanical strengths. Stabilization/solidification experiments demonstrated that MSWI FA (70 wt%) could be recycled by MgO-GGBS binder (30 wt%) into blocks with desirable 28-day compressive strengths (3.9 MPa) and PTEs immobilization efficiencies (99.8% for Zn and 99.7% for Pb). This work provides mechanistic insights on the immobilization mechanisms of PTEs in CaO/MgO-GGBS systems and suggests a promising MgO-GGBS binder for low-carbon treatment of MSWI FA.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Eliminação de Resíduos/métodos , Material Particulado , Carbono , Óxido de Magnésio , Chumbo , Metais Pesados/análise , Incineração/métodos , Resíduos Sólidos/análise
7.
Environ Sci Technol ; 56(13): 9398-9407, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35735903

RESUMO

Electroplating sludge is a hazardous waste due to its high potential to leach toxic elements into the natural environment. To alleviate this issue, we tailored magnesium phosphate cement (MPC) as a low-carbon material for stabilization/solidification (S/S) of Zn-rich electroplating sludge. The interaction between MPC and ZnO was investigated to clarify the precipitate chemistry, microstructure transition, and chemical environment of Zn species in the MPC-treated Zn sludge system. Comprehensive characterization (by X-ray diffraction (XRD), 31P nuclear magnetic resonance (NMR), and extended X-ray absorption fine structure spectroscopy (EXAFS)) and thermodynamic modeling results revealed that the incorporated ZnO preferentially reacted with phosphate to form Zn3(PO4)2·2H2O/Zn3(PO4)2·4H2O, changing the orthophosphate environment in the MPC system. Stronger chemical bonding between Zn and phosphate in comparison to the bonding between Mg and phosphate also resulted in the formation of amorphous Zn3(PO4)2·2H2O/Zn3(PO4)2·4H2O. Zn3(PO4)2·4H2O precipitate appears to predominate at high {K+}{H+}{HPO42-} values, and the formation of Zn3(PO4)2·2H2O/Zn3(PO4)2·4H2O competed for the Mg sites in the MPC system, leading to the inhibition of formation of Mg-phosphate precipitates. Overall, this work uncovers the precipitate chemistry and microstructure transition of Zn species in the MPC system, providing new insights into the sustainable S/S of Zn-contaminated wastes by adopting MPC.


Assuntos
Metais Pesados , Óxido de Zinco , Galvanoplastia , Compostos de Magnésio , Metais Pesados/química , Fosfatos/química , Esgotos/química , Zinco/química
8.
Environ Sci Technol ; 56(3): 1724-1735, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34978795

RESUMO

Electron transfer mediated by iron minerals is considered as a critical redox step for the dynamics of pollutants in soil. Herein, we explored the reduction process of Cr(VI) with different crystalline ferric oxyhydroxides in the presence of pyrogenic carbon (biochar). Both low- and high-crystallinity ferric oxyhydroxides induced Cr(VI) immobilization mainly via the sorption process, with a limited reduction process. However, the Cr(VI) reduction immobilization was inspired by the copresence of biochar. Low-crystallinity ferric oxyhydroxide had an intense chemical combination with biochar and strong sorption for Cr(VI) via inner-sphere complexation, leading to the indirect electron transfer route for Cr(VI) reduction, that is, the electron first transferred from biochar to iron mineral through C-O-Fe binding and then to Cr(VI) with Fe(III)/Fe(II) transformation on ferric oxyhydroxides. With increasing crystallinity of ferric oxyhydroxides, the direct electron transfer between biochar and Cr(VI) became the main electron transfer avenue for Cr(VI) reduction. The indirect electron transfer was suppressed in the high-crystallinity ferric oxyhydroxides due to less sorption of Cr(VI), limited combination with biochar, and higher iron stability. This study demonstrates that electron transfer mechanisms involving iron minerals change with the mineral crystallization process, which would affect the geochemical process of contaminants with pyrogenic carbon.


Assuntos
Compostos Férricos , Poluentes Químicos da Água , Adsorção , Carbono , Carvão Vegetal/química , Cromo/química , Elétrons , Compostos Férricos/química , Ferro/química , Minerais , Poluentes Químicos da Água/análise
9.
Environ Sci Technol ; 56(7): 4187-4198, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35289167

RESUMO

Biochar application is a promising strategy for the remediation of contaminated soil, while ensuring sustainable waste management. Biochar remediation of heavy metal (HM)-contaminated soil primarily depends on the properties of the soil, biochar, and HM. The optimum conditions for HM immobilization in biochar-amended soils are site-specific and vary among studies. Therefore, a generalized approach to predict HM immobilization efficiency in biochar-amended soils is required. This study employs machine learning (ML) approaches to predict the HM immobilization efficiency of biochar in biochar-amended soils. The nitrogen content in the biochar (0.3-25.9%) and biochar application rate (0.5-10%) were the two most significant features affecting HM immobilization. Causal analysis showed that the empirical categories for HM immobilization efficiency, in the order of importance, were biochar properties > experimental conditions > soil properties > HM properties. Therefore, this study presents new insights into the effects of biochar properties and soil properties on HM immobilization. This approach can help determine the optimum conditions for enhanced HM immobilization in biochar-amended soils.


Assuntos
Recuperação e Remediação Ambiental , Metais Pesados , Poluentes do Solo , Carvão Vegetal , Aprendizado de Máquina , Solo , Poluentes do Solo/análise
10.
Crit Rev Environ Sci Technol ; 53(11): 1148-1172, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37090929

RESUMO

Phosphorus (P) as an essential nutrient for life sustains the productivity of food systems; yet misdirected P often accumulates in wastewater and triggers water eutrophication if not properly treated. Although technologies have been developed to remove P, little attention has been paid to the recovery of P from wastewater. This work provides a comprehensive review of the state-of-the-art P removal technologies in the science of wastewater treatment. Our analyses focus on the mechanisms, removal efficiencies, and recovery potential of four typical water and wastewater treatment processes including precipitation, biological treatment, membrane separation, and adsorption. The design principles, feasibility, operation parameters, and pros & cons of these technologies are analyzed and compared. Perspectives and future research of P removal and recovery are also proposed in the context of paradigm shift to sustainable water treatment technology.

11.
Environ Res ; 212(Pt E): 113495, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35660402

RESUMO

To prevent the COVID-19 transmission, personal protective equipment (PPE) and packaging materials have been extensively used but often managed inappropriately, generating huge amount of plastic waste. In this review, we comprehensively discussed the plastic products utilized and the types and amounts of plastic waste generated since the outbreak of COVID-19, and reviewed the potential treatments for these plastic wastes. Upcycling of plastic waste into biochar was addressed from the perspectives of both environmental protection and practical applications, which can be verified as promising materials for environmental protections and energy storages. Moreover, novel upcycling of plastic waste into biochar is beneficial to mitigate the ubiquitous plastic pollution, avoiding harmful impacts on human and ecosystem through direct and indirect micro-/nano-plastic transmission routes, and achieving the sustainable plastic waste management for value-added products, simultaneously. This suggests that the plastic waste could be treated as a valuable resource in an advanced and green manner.


Assuntos
COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Carvão Vegetal , Ecossistema , Humanos , Pandemias/prevenção & controle , Plásticos
12.
Environ Res ; 207: 112179, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624271

RESUMO

The accumulation of microplastics (MPs) and nanoplastics (NPs) in terrestrial and aquatic ecosystems has raised concerns because of their adverse effects on ecosystem functions and human health. Plastic waste management has become a universal problem in recent years. Hence, sustainable plastic waste management techniques are vital for achieving the United Nations Sustainable Development Goals. Although many reviews have focused on the occurrence and impact of micro- and nanoplastics (MNPs), there has been limited focus on the management of MNPs. This review first summarizes the ecotoxicological impacts of plastic waste sources and issues related to the sustainable management of MNPs in the environment. This paper then critically evaluates possible approaches for incorporating plastics into the circular economy in order to cope with the problem of plastics. Pollution associated with MNPs can be tackled through source reduction, incorporation of plastics into the circular economy, and suitable waste management. Appropriate infrastructure development, waste valorization, and economically sound plastic waste management techniques and viable alternatives are essential for reducing MNPs in the environment. Policymakers must pay more attention to this critical issue and implement appropriate environmental regulations to achieve environmental sustainability.


Assuntos
Microplásticos , Poluentes Químicos da Água , Ecossistema , Poluição Ambiental , Humanos , Plásticos , Poluentes Químicos da Água/análise
13.
J Strength Cond Res ; 36(8): 2349-2359, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065703

RESUMO

ABSTRACT: Lee, DCW, Ali, A, Sheridan, S, Chan, DKC, and Wong, SHS. Wearing compression garment enhances central hemodynamics? a systematic review and meta-analysis. J Strength Cond Res 36(8): 2349-2359, 2022-Compression garments (CG) are believed to enhance exercise performance and recovery by improving central hemodynamic responses. However, evidence is inconclusive. We performed a systematic review and meta-analysis to determine the effect of wearing CG at rest or after a physiological challenge on central hemodynamic responses, including cardiac output, stroke volume (SV), heart rate (HR), systolic blood pressure, diastolic blood pressure (DBP), and systemic vascular resistance in healthy individuals. The English language searches of the electronic databases SPORTDiscus, MEDLINE, and Web of Science were conducted from November 2018-February 2019. The studies involved were limited to the following: (a) original articles; (b) randomized controlled trials; (c) monitoring of central hemodynamic responses (either at rest or after a physiological challenge: maximal exercise or orthostatic challenge); and (d) healthy individuals. Of the 786 studies identified, 12 were included in the systematic review and meta-analysis. Meta-analysis was performed by the restricted maximum likelihood method. The results indicated that the effect size (ES) of wearing CG on improving central hemodynamic responses was large overall (Hedges' g = 0.55) and was large in SV (Hedges' g = 1.09) and HR (Hedges' g = 0.65). Subgroup analysis showed that the ESs in "post-physiological challenge" was large in overall (Hedges' g = 0.98), SV (Hedges' g = 1.78), HR (Hedges' g = 1.10), and DBP (Hedges' g = 0.75). Their ESs in "at rest" were not significant in all central hemodynamic responses, apart from a significant medium ES observed in SV (Hedges' g = 0.44). Healthy individuals who wear CG have marked improvement in central hemodynamic responses, particularly after a physiological challenge. More pronounced effects of CG are observed in increasing SV and reducing HR.


Assuntos
Exercício Físico , Hemodinâmica , Débito Cardíaco , Vestuário , Humanos , Resistência Vascular
14.
Environ Sci Technol ; 55(10): 7004-7014, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33913698

RESUMO

Nitrogen-doped graphitic biochar (NBC) has boosted the development of nonradical peroxymonosulfate (PMS) activation in environmental remediation. However, the specific role of nitrogen species played in NBC-based nonradical carbocatalysis remains vaguely interpreted. To pinpoint the critical nitrogen speciation, a sophisticated thermo-mechanochemical manipulation was exploited to prepare a series of NBCs with similar dimensional structures and oxygen levels but different nitrogen species (i.e., dopants and vacancies). Different from conventional perspectives, nonradical NBC-based carbocatalysis was found to be preferably determined by the nitrogen vacancies more than their parent nitrogen dopants. Raman depth analysis evidenced that a complete transformation of nitrogen dopants into nitrogen vacancies could be achieved at 800 °C, where an excellent nonradical abatement of 4-chlorophenol (4-CH, 90.9% removal) was found for the NBC800 with a low PMS consumption (1.24 mM). According to PMS adsorption experiments, nitrogen vacancies exhibited the highest affinity toward the PMS molecules compared to nitrogen dopants, which accounted for the superior carbocatalysis. Electron paramagnetic resonance and Raman spectroscopic analyses indicated that the original PMS molecules were bound to positively charged nitrogen vacancies, and a robust metastable complex (*HSO5-) evolved subsequently via hydrogen abstraction by adjacent persistent free radicals. In situ Raman techniques could be adopted to estimate the level of nitrogen vacancies associated with the polarization of electron distribution. The flexible feature and practical prospects of nitrogen vacancy-based carbocatalysis were also observed in the remediation of simulated phenolic industrial wastewater. Overall, this study unravels the dilemma in the current NBC-based nonradical carbocatalysis and advances our understanding of nitrogen doping technology for next-generation biochar design.


Assuntos
Grafite , Adsorção , Carvão Vegetal , Nitrogênio , Peróxidos
15.
Environ Sci Technol ; 55(11): 7167-7185, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33970611

RESUMO

There is considerable debate about the sustainability of the hydraulic fracturing (HF) water cycle in North America. Recently, this debate has expanded to China, where HF activities continue to grow. Here, we provide a critical review of the HF water cycle in China, including water withdrawal practices and flowback and produced water (FPW) management and their environmental impacts, with a comprehensive comparison to the U.S. and Canada (North America). Water stress in arid regions, as well as water management challenges, FPW contamination of aquatic and soil systems, and induced seismicity are all impacts of the HF water cycle in China, the U.S., and Canada. In light of experience gained in North America, standardized practices for analyzing and reporting FPW chemistry and microbiology in China are needed to inform its efficient and safe treatment, discharge and reuse, and identification of potential contaminants. Additionally, conducting ecotoxicological studies is an essential next step to fully reveal the impacts of accidental FPW releases into aquatic and soil ecosystems in China. From a policy perspective, the development of China's unconventional resources lags behind North America's in terms of overall regulation, especially with regard to water withdrawal, FPW management, and routine monitoring. Our study suggests that common environmental risks exist within the world's two largest HF regions, and practices used in North America may help prevent or mitigate adverse effects in China.


Assuntos
Fraturamento Hidráulico , Poluentes Químicos da Água , Canadá , China , Ecossistema , América do Norte , Águas Residuárias , Água , Ciclo Hidrológico , Poluentes Químicos da Água/análise
16.
Environ Res ; 202: 111635, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34242674

RESUMO

Phosphorus (P) availability is closely related to the distributions of pH, O2 and phosphatase activities in the rhizosphere of plants growing in soils and sediments. In this study, the P uptake processes and mechanisms of Vallisneria natans (V. natans) during two vegetation periods (i.e., week three and six) were revealed using three noninvasive 2D imaging techniques: planar optode (PO), diffusive gradients in thin films (DGT) and zymography. The results showed that increased phosphatase activity, O2 concentration and root-induced acidification were observed together in the rhizosphere of root segments and tips. In week three, when V. natans was young, the flux of DGT-labile P accumulated more in the rhizosphere in comparison with the bulk sediment. This was because increased phosphatase activity (of up to 35%) and root-induced acidification (with pH decreasing by up to 0.25) enhanced P acquisition of V. natans by the third week. However, the flux of DGT-labile P turned to depletion during weeks three to six of V. natans growth, after Fe plaque formed at the matured stage. The constant hydrolysis of phosphatase and acidification could not compensate for the P demand of the roots by the sixth week. At this stage, Fe plaque become the P pool, due to P fixation with solid Fe(III) hydroxides. Subsequently, V. natans roots acquired P from Fe plaque via organic acid complexation of Fe(III).


Assuntos
Hydrocharitaceae , Poluentes Químicos da Água , Compostos Férricos , Sedimentos Geológicos , Fósforo , Rizosfera , Solo , Poluentes Químicos da Água/análise
17.
Eur J Appl Physiol ; 121(7): 2091-2100, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33835198

RESUMO

PURPOSE: To investigate sports compression garment (CG)-induced recovery hemodynamics and their potential impact on subsequent cycling performance. METHODS: In a randomized crossover design, 13 physically active men (20.9 ± 1.4 years; 65.9 ± 7.8 kg; 173.3 ± 4.8 cm; peak power output 254.2 ± 27.2 W) underwent 2 experimental trials. During each experimental trial, the subjects performed 20-min fatiguing preload cycling followed by 60-min passive recovery wearing either a sports CG (28.6 ± 9.4 mmHg) or gymnastic pants (CON). A 5-min all-out cycling performance test was subsequently conducted and power output and cadence were recorded. Cardiac output (CO) and stroke volume (SV) were measured using Doppler ultrasound (USCOM®). Heart rate (HR), blood lactate [BLa-], ratings of perceived exertion (RPE), leg muscle soreness (LMS), mean arterial pressure (MAP) and systemic vascular resistance (SVR) were monitored at 5, 15, 30, 45, 60 min during passive recovery. RESULTS: During the subsequent 5-min all-out cycling performance test, power output (215.2 ± 24.0 vs. 210.8 ± 21.5 W, CG vs. CON) and cadence (72.5 ± 3.8 vs. 71.2 ± 4.8 rpm, CG vs. CON) were higher in CG than CON (P < 0.05). SV was higher at 15, 30 and 45 min (P < 0.05), CO was higher at 5 and 45 min (P < 0.05), HR was lower at 15 and 30 min (P < 0.05) and [BLa-] was lower at 5 and 15 min (P < 0.05) during passive recovery, while LMS was lower at all time-points (P < 0.05) compared with CON. CONCLUSION: Sports CG improves subsequent cycling performance by enhancing hemodynamic responses and attenuating perceived muscle soreness during passive recovery in physically active men.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Meias de Compressão , Débito Cardíaco/fisiologia , Estudos Cross-Over , Frequência Cardíaca/fisiologia , Humanos , Lactatos/sangue , Masculino , Mialgia/prevenção & controle , Esforço Físico/fisiologia , Volume Sistólico/fisiologia , Ultrassonografia Doppler , Resistência Vascular , Adulto Jovem
18.
J Environ Manage ; 298: 113530, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34411800

RESUMO

Mono- and co-sorption of the three antibiotics i.e., norfloxacin (NOR), sulfamerazine (SMR) and oxytetracycline (OTC), to raw and NH4+-modified cassava waste biochar added to aqueous solutions were investigated. The NH4+-modified biochar showed higher sorption affinity for both NOR and SMR than the raw biochar, while the raw biochar showed higher sorption affinity for OTC than the modified biochar. The highest sorption to both biochars in both the mono- and competitive sorption systems was found for OTC followed by NOR and SMR. Sorption equilibrium in all systems analyzed was reached within 15 h. Electrostatic interactions among the ionic antibiotics in the multicomponent solution increased NOR and SMR sorption to both biochars. Antibiotics' mono- and co-sorption to biochars decreased with increasing solution pH. The co-sorption of NOR and SMR to the two biochars was regulated by π-π electron-donor-acceptor (EDA) interactions; besides, electrostatic interactions and Hydrogen (H-) bonding played an important part. Cation bridging might have been a potential mechanism to contribute to SMR sorption to the raw biochar, and OTC sorption to the NH4+-modified biochar. These observations will improve our understanding of the simultaneous removal of multiple antibiotics from water or wastewater.


Assuntos
Compostos de Amônio , Manihot , Adsorção , Antibacterianos , Carvão Vegetal , Água
19.
Angew Chem Int Ed Engl ; 60(2): 624-629, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33078542

RESUMO

The heterogeneous metal-organic framework Bi-BTC successfully catalyzed the synthesis of para-xylene from bio-based 2,5-dimethylfuran and acrylic acid in a promising yield (92 %), under relatively mild conditions (160 °C, 10 bar), and with a low reaction-energy barrier (47.3 kJ mol-1 ). The proposed reaction strategy also demonstrates a remarkable versatility for furan derivatives such as furan and 2-methylfuran.

20.
Small ; 16(37): e2002802, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32797713

RESUMO

Traditional liquid marbles (LMs), liquid droplets encapsulated by hydrophobic particles at the liquid-gas interface, are restricted by their short lifetime and low heat transfer efficiency. Herein, a new paradigm for LMs immersed in various liquid mediums with massive enhanced heat transfer and spatial recognition is designed; without compromising the structural integrity, the lifetime of the liquid marbles in liquid (LMIL) is extended by ≈1000 times compared to classical LMs in air or naked droplets in organic reagents. The LMIL shows promising reverse structural re-configurability while under external stimuli and maintaining their functionality for a very long period of time (≈weeks). These superior behaviors are further exploited as a miniature reactor with prolonged lifetimes and excellent temperature control, combined with its feasible operation, new opportunities will open up in the advanced chemical and biomedical engineering fields. It is also shown that LMIL can be applied in methylene blue degradation and 3D in-vitro yeast cell cultures. These findings have important implications for real-world use of LMs, with a number of applications in cell culture technology, lab-in-a-drop, polymerization, encapsulation, formulation, and drug delivery.


Assuntos
Carbonato de Cálcio , Azul de Metileno , Interações Hidrofóbicas e Hidrofílicas
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