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1.
Phys Rev Lett ; 132(24): 246502, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949367

RESUMO

Disorder at etched edges of graphene quantum dots (GQD) enables random all-to-all interactions between localized charges in partially filled Landau levels, providing a potential platform to realize the Sachdev-Ye-Kitaev (SYK) model. We use quantum Hall edge states in the graphene electrodes to measure electrical conductance and thermoelectric power across the GQD. In specific temperature ranges, we observe a suppression of electric conductance fluctuations and slowly decreasing thermoelectric power across the GQD with increasing temperature, consistent with recent theory for the SYK regime.

2.
PLoS One ; 19(4): e0300387, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635536

RESUMO

Although biochar application to soils has been found to increase soil quality and crop yield, the biochar dispersion extent and its impacts on native soil organic carbon (SOC) has received relatively little attention. Here, the vertical and lateral migration of fine, intermediate and coarse-sized biochar (<0.5, 0.5-1 and 1-5 mm, respectively), applied at low and high doses (1.5-2 and 3-4% w/w, respectively), was tracked using stable isotope methods, along with its impact on native SOC stocks. Biochar was homogeneously mixed into the surface layer (0-7 cm depth) of a loamy sandy Acrisol in Zambia. After 4.5 y, 38-75% of the biochar carbon (BC) was lost from the applied layer and 4-25% was detected in lower soil layers (7-30 cm). Estimating BC mineralization to be no more than 8%, 25-60% was likely transported laterally out of the experimental plots. This conclusion was supported by observations of BC in the control plot and in soils up to 2 m outside of the experimental plots. These processes were likely progressive as recovery of BC in similar plots 1 year after application was greater in both surface and lower soil layers than after 4.5 y. Fine and intermediate-sized BC displayed the greatest downward migration (25.3 and 17.9%, respectively), particularly when applied at lower doses, suggesting its movement through soil inter-particle spaces. At higher dosages, fine and intermediate-sized particles may have clogged pore, so coarse biochar displayed the greatest downward migration when biochar was applied at higher doses. In the BC treatment plot soil profiles, native SOC stocks were reduced by 2.8 to 24.5% (18.4% on average), i.e. positive priming. However, some evidence suggested that the soils may switch to negative priming over time. The dispersion of biochar in soil should be considered when evaluating biochar's agronomic benefits and environmental effects.


Assuntos
Carbono , Solo , Carvão Vegetal , Agricultura/métodos
3.
Chemosphere ; 355: 141750, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522671

RESUMO

Activated carbon (AC) has important industrial and environmental applications as it has excellent abilities to sorb contaminants such as per- and polyfluoroalkyl substances (PFAS). Current research aims to develop activated biochars (AB) from renewable biomass to replace AC that is produced from fossil feedstock. Both AC and AB are primarily comprised of condensed aromatic carbon (ConAC), the component that is the focus of this study. ConAC is characterized to determine its relationship with biochar activation conditions and PFAS sorption, which are understudied at present. Benzenepolycarboxylic acid (BPCA) markers for ConAC were quantified in steam-activated biochars (AB-Steam) and carbon dioxide-activated biochars (AB-CO2) prepared from waste timber at different temperatures (800, 850, 900 °C) and molar ratios of feedstock-carbon:steam (0.50 - 1.25). A non-activated biochar was also included as a reference. ConAC relative to total organic carbon content was higher in AB-Steam than in AB-CO2 (92 ± 2 % vs. 81 ± 11%). The ratio of benzenehexa- (B6CA) to benzenepentacarboxylic (B5CA) acids revealed that AB-Steam also had larger ConAC clusters than AB-CO2. These findings provide novel evidence that steam activation is more effective than CO2 activation in creating ConAC. To assess how ConAC impacts AB sorption abilities, AB-Steam were used to remediate PFAS from contaminated soils. The observed strong correlations between ConAC content and sorption of long-chain PFAS suggest the importance of hydrophobic interactions between PFAS tails and ConAC. Poor correlations for short-chain PFAS, on the other hand, indicated the existence of electrostatic repulsion interactions between PFAS head groups and ConAC. Collectively, these results explain the great ability of AB-Steam to sorb PFAS from contaminated soils (up to 100% remediation). More broadly, this work demonstrates that the BPCA method can be a valuable tool to assess the quality of biochars and other carbonaceous sorbents in relation to their production conditions or contaminant sorption abilities.


Assuntos
Dióxido de Carbono , Fluorocarbonos , Vapor , Adsorção , Carvão Vegetal/química , Solo
4.
Semin Pediatr Neurol ; 47: 101076, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37919035

RESUMO

SLEEP IN AUTISM SPECTRUM DISORDER AND ATTENTION DEFICIT HYPERACTIVITY DISORDER: Kanwaljit Singh, Andrew W. Zimmerman Seminars in Pediatric Neurology Volume 22, Issue 2, June 2015, Pages 113-125 Sleep problems are common in autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). Sleep problems in these disorders may not only worsen daytime behaviors and core symptoms of ASD and ADHD but also contribute to parental stress levels. Therefore, the presence of sleep problems in ASD and ADHD requires prompt attention and management. This article is presented in 2 sections, one each for ASD and ADHD. First, a detailed literature review about the burden and prevalence of different types of sleep disorders is presented, followed by the pathophysiology and etiology of the sleep problems and evaluation and management of sleep disorders in ASD and ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtornos do Sono-Vigília , Criança , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/terapia , Prevalência , Sono/fisiologia , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/epidemiologia
5.
ANZ J Surg ; 93(12): 2857-2863, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37658592

RESUMO

BACKGROUND: Laparoscopic gastric bypass (LGB) is an increasingly utilized approach to bariatric surgery in Australia. A high proportion of those procedures are revisional due to Australia's legacy of laparoscopic adjustable gastric banding (LAGB), which is not the case internationally. The aim of this study was to compare post-operative outcomes in an Australian general foregut surgery unit against benchmarks published in the literature. METHODS: This is retrospective cohort study of morbidly obese patients undergoing primary or revisional laparoscopic Roux-en-Y gastric bypass (RYGB) or laparoscopic one anastomosis gastric bypass (OAGB) with the two senior authors between 5 May 2015 and 27 June 2019. Perioperative data for the unit's first 100 cases were collected prospectively, stored on a unit database and analysed. Post-operative complications at 30 days, 90 days, mortality, length of hospital stay, and Defined Adverse Events were chosen as indicators of the perioperative outcome (as defined in the Monash Bariatric Surgery Registry). RESULTS: In this cohort, 35% of procedures were RYGB and 65% were OAGB. The majority (58%) were revisional procedures. Most patients (74%) were female. The median age was 50. The comorbidity profile of the population was similar to those published internationally. The median hospital stay was 4 days. There was no mortality. Early complications occurred in 9% of patients, with 3% occurring late. CONCLUSION: Outcomes of our first 100 cases are comparable with those recorded in the literature, notwithstanding a much higher proportion of revisional cases. LGB can be safely introduced in Australian general foregut surgery units by experienced laparoscopic surgeons.


Assuntos
Derivação Gástrica , Gastroplastia , Laparoscopia , Obesidade Mórbida , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Derivação Gástrica/efeitos adversos , Obesidade Mórbida/cirurgia , Obesidade Mórbida/epidemiologia , Gastroplastia/efeitos adversos , Estudos Retrospectivos , Austrália/epidemiologia , Laparoscopia/métodos , Reoperação/métodos , Resultado do Tratamento
6.
RSC Adv ; 13(21): 14384-14392, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37180009

RESUMO

Biochar has been recognized as a promising sustainable adsorbent for removing pollutants from wastewater. In this study, two natural minerals, attapulgite (ATP) and diatomite (DE) were co-ball milled with sawdust biochar (pyrolyzed at 600 °C for 2 h) at ratios of 10-40% (w/w) and examined the ability of methylene blue (MB) to be removed from aqueous solutions by them. All the mineral-biochar composites sorbed more MB than both ball milled biochar (MBC) and ball milled mineral alone, indicating there was a positive synergy in co-ball milling biochar with these minerals. The 10% (w/w) composites of ATP:BC (MABC10%) and DE:BC (MDBC10%) had the greatest MB maximum adsorption capacities (modeled by Langmuir isotherm modeling) and were 2.7 and 2.3 times that of MBC, respectively. The adsorption capacities of MABC10% and MDBA10% were 183.0 mg g-1 and 155.0 mg g-1 at adsorption equilibrium, respectively. These improvements can be owing to the greater content of oxygen-containing functional groups and higher cation exchange capacity of the MABC10% and MDBC10% composites. In addition, the characterization results also reveal that pore filling, π-π stacking interactions, hydrogen bonding of hydrophilic functional groups, and electrostatic adsorption of oxygen-containing functional groups also contribute prominently to the adsorption of MB. This, along with the greater MB adsorption at higher pH and ionic strengths, suggests the roles in MB adsorption was an electrostatic interaction and an ion exchange mechanism. These results demonstrate that mineral-biochar composites prepared by co-ball milling treatment were promising sorbents of ionic contaminants for environmental applications.

7.
Environ Pollut ; 327: 121543, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37019262

RESUMO

Biochar is a promising environmental contaminant remediation agent because of its adsorptive and catalytic properties. However, the environmental effects of persistent free radicals (PFRs) produced by biomass pyrolysis (biochar production) are still poorly understood, though they have received increasing research attention in recent years. Although PFRs both directly and indirectly mediate biochar's removal of environmental pollutants, they also have the potential to cause ecological damage. In order to support and sustain biochar applications, effective strategies are needed to control the negative effects of biochar PFRs. Yet, there has been no systematic evaluation of the environmental behavior, risks, or management techniques of biochar PFRs. Thus, this review: 1) outlines the formation mechanisms and types of biochar PFRs, 2) evaluates their environmental applications and potential risks, 3) summarizes their environmental migration and transformation, and 4) explores effective management strategies for biochar PFRs during both production and application phases. Finally, future research directions are recommended.


Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Carvão Vegetal , Radicais Livres
8.
J Hazard Mater ; 445: 130449, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36459882

RESUMO

The use of sewage sludge to produce biochar-based sorbents for per- and polyfluoroalkyl substances (PFAS) removal from water and soil may be an economically and environmentally sustainable waste management option. This study compared the sorption of six perfluorinated carboxylic acids (PFCAs) by two sewage sludge biochars (SSBCs) and one wood chip biochar (WCBC), dry pyrolyzed at 700 °C. Batch sorption tests were conducted by adding individual PFCAs and a PFCA-mixture to pure biochars and mixtures of biochar and a sandy soil (1.3% TOC). PFAS-sorption to the SSBCs exhibited log-linear biochar-water distribution coefficients (log Kd), comparable to those previously reported for commercial activated carbons (e.g., 5.73 ± 0.02 for perfluorooctanoic acid at 1 µg/L). The strong sorption of PFCAs was attributed to the SSBCs relatively high pore volumes in the pore size range that can accommodate these compounds. Sorption was attenuated by the presence of soil (by factors 3-10), by the presence of a mixture of PFCAs (by factors of 6-532) and by both together (by factors of 8-6581), indicating strongly competitive sorption between PFCA-congeners, and less severe sorption attenuation by soil organic matter. These findings could enable sustainable value chains for SSBs in soil remediation and water filtration solutions.


Assuntos
Fluorocarbonos , Poluentes do Solo , Esgotos , Carvão Vegetal , Solo , Água , Adsorção , Poluentes do Solo/análise
9.
Chemosphere ; 313: 137410, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36455661

RESUMO

Advanced biosorbents increasingly attract attention for their application in environment remediation. Here, a facile one-step approach to alkaline ball milling was used to synthesize a porous peanut hull biosorbent without heating. The alkaline ball-milled peanut-hull (ABP) biosorbent was characterized for its ability to remove Congo red (CR), titan yellow (TY), and methyl violet (MV) from aqueous solutions. ABP processed abundant O-containing functional groups and developed porosity, resulting in maximum sorption capacities of 4864.4 (CR), 455.9 (TY), and 126.1 (MV) mg g-1. Freundlich isotherm and PSO kinetic models best fit the anionic dye's (CR and TY) adsorption by ABP, indicating multiple mechanisms might control the adsorption process. Freundlich and PFO kinetics models best described cationic MV adsorption by ABP, suggesting the adsorption of cationic dye could also be governed by multi-mechanisms but less heterogeneous than that of anionic dye. The results suggest that alkaline ball-milling is promising approach to converting biomass into advanced biosorbents for organic dyes, especially anionic ones.


Assuntos
Arachis , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Corantes , Vermelho Congo , Adsorção , Cinética , Água , Violeta Genciana , Concentração de Íons de Hidrogênio
10.
Chemosphere ; 309(Pt 1): 136610, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36181850

RESUMO

New classes of biosorbents are needed for various environment remediation applications. Thus, a facile and benign approach to synthesize porous biosorbents was developed using acidic or alkaline one-step ball milling of hickory wood biomass (AcBH and AlBH, respectively) without any external heat treatment, and their properties were compared. AcBH and AlBH were richer in O-containing functional groups, had enhanced porous structure and greater ability to remove crystal violet (CV, 476.4 mg g-1) and Congo red (CR, 221.8 mg g-1) dyes from aqueous solution, respectively, relative to hickory wood ball milled at neutral pH. Freundlich isotherm and pseudo second order kinetic models best fitted CR and CV adsorption onto biosorbents, indicating a mainly surface complexation adsorption mechanism. Further, both sorbents exhibited excellent stability and dye adsorption reusability. These results demonstrate that acidic and alkaline one-step ball milling is a facile and efficient approach for converting wood biomass into environmentally friendly biosorbents.


Assuntos
Corantes , Poluentes Químicos da Água , Vermelho Congo , Violeta Genciana , Madeira/química , Poluentes Químicos da Água/análise , Água/química
11.
J Environ Manage ; 316: 115275, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35658253

RESUMO

Hydrothermal liquid products (HLPs) produced by hydrothermal treatment (HTT) contain a large amount of nitrogen, phosphorus and other substances, while the environmental problems caused by arbitrary discharge. This work explored the effects of temperature, reaction time and solid-liquid ratio on the chemistry of HLPs of two different distillers grains, with a focus on nutrient composition. Increased HTT temperature was related to increased HLPs pH, dissolved organic carbon content, and aromaticity, and decreased electrical conductivity. Maximum nutrient extraction efficiencies observed for NH4+-N, NO3--N and PO43- were 92.0, 89.9, and 94.3%, respectively. Response surface methodology showed that the release of nutrient extraction efficiency was the greatest at the hydrothermal treatment of 200 °C for 1 h, and using a solid/liquid ratio of 10%. Comparative studies, the nutritional value of HLPs are appropriate for use as an agricultural fertilizer, and its use as a substitute for synthetic fertilizers could increase the sustainability and profitability of farming.


Assuntos
Fertilizantes , Nitrogênio , Agricultura , Fertilizantes/análise , Nitrogênio/análise , Valor Nutritivo , Fósforo
12.
Chemosphere ; 305: 135475, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35760137

RESUMO

In this study, biochar derived from bamboo pretreated with aluminum salt was synthesized for the removal of two sulfonamide antibiotics, sulfamethoxazole (SMX) and sulfapyridine (SPY), from wastewater. Batch sorption experiments showed that Al-modified bamboo biochar (Al-BB-600) removed both sulfonamides effectively with the maximum sorption capacity of 1200-2200 mg/kg. The sorption mechanism was mainly controlled by hydrophobic, π-π, and electrostatic interactions. Fixed bed column experiments with Al-modified biochar packed in different dosages (250, 500 and 1000 mg) and flow rates (1, 2 and 4 mL/min) showed the dosage of 1000 mg and flow rate of 1 mL/min performed the best for the removal of both SMX and SPY from wastewater. Among the breakthrough (BT) models used to evaluate the fixed bed filtration performance of Al-BB-600, the Yan model best described the BT behavior of the two sulfonamides, suggesting that the adsorption process involved multiple rate-liming factors such as mass transfer at the solid surface and diffusion Additionally, the Bed Depth Service Time (BDST) model results indicated that Al-BB-600 can be efficiently used in fixed bed column for the removal of both SMX and SPY in scaled-up continuous wastewater flow operations. Therefore, Al-modified biochar can be considered a reliable sorbent in real-world application for the removal of SMX and SPY from wastewater.


Assuntos
Sasa , Poluentes Químicos da Água , Adsorção , Antibacterianos/química , Carvão Vegetal/química , Sulfametoxazol/química , Sulfapiridina , Águas Residuárias , Poluentes Químicos da Água/química
13.
Bioresour Technol ; 355: 127274, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35533889

RESUMO

Biochar derived from corn stalk doping with activated carbon was produced by microwave-assisted pyrolysis and applied to sorb volatile organic compounds (VOCs: benzene and o-xylene). Specific surface area (SSA), total pore volume (TPV) and micropore volume (MV) of microwave biochar increased with increasing microwave power with the maximum values 325.2 m2·g-1, 0.181 mL·g-1 and 0.1420 mL·g-1, respectively. Adsorption capacities of benzene and o-xylene on microwave biochar ranged 6.82-54.75 mg·g-1 and 7.43-48.73 mg·g-1, which were separate positively related with SSA, TPV, and MV. Benzene adsorption was mainly dominated by surface interaction and partition mechanisms, while o-xylene adsorption was governed by pore filling. The adsorption capacities of microwave biochar for benzene and o-xylene decreased by only 0.30% and 0.99% on the 5th cycle that illustrated the reasonably good reusability of microwave biochar. The results of this research demonstrate that microwave biochar is a promising adsorbent for VOCs removal.


Assuntos
Pirólise , Compostos Orgânicos Voláteis , Adsorção , Benzeno , Carvão Vegetal , Micro-Ondas
14.
Bioresour Technol ; 348: 126831, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35143986

RESUMO

Biosorbent has attracted considerable attention recently for use in environment remediation and pollution control. Here, a simple and efficient method of one-step alkaline ball milling was designed to prepare porous hickory biosorbent without any thermal treatments. The products were characterized for their ability to remove methyl violet (MV) and titan yellow (TY) organic dyes from aqueous solutions. The one-step alkaline ball milled hickory (OABMH) biosorbent exhibited mesoporous microstructure, homogeneous morphology, and a diversity of oxygen-containing functional groups. Furthermore, OABMH could sorb 212.2 mg g-1 MV and 5.6 mg g-1 TY polar dyes, respectively, mainly through the surface complexation mechanism. Freundlich adsorption isotherm and intraparticle diffusion kinetic models best described MV adsorption by OABMH biosorbents. The results indicate that one-step alkaline ball milling technique is an efficient and economical approach for converting biomass into advanced biosorbents for environment remediation and water treatment.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Corantes , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Madeira/química
15.
Sci Total Environ ; 827: 153996, 2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35189217

RESUMO

A series of microwave biochars derived from wheat straw in the presence of a granulated activated carbon (GAC) catalyst, using a range of microwave conditions, were produced, characterized and tested as sorbents of three benzene series volatile organic compounds (VOCs). The microwave biochar with the greatest specific surface area (SSA), total pore volume (TPV), and micropore volume (312.62 m2 g-1, 0.2218 cm3 g-1, and 0.1380 cm3 g-1, respectively), were produced with 1:3 biomass:GAC catalyst mass ratio, 10 min microwave irradiation time, and at 500 W power level (WB500). Maximum adsorption capacities of WB500 to benzene, toluene and o-xylene were 53.9 mg g-1, 75.8 mg g-1 and 63.0 mg g-1, respectively, and were directly correlated to microwave biochar properties such as SSA, TPV or micropore volume, but were also influenced by VOC properties such as molecular polarity and boiling point. Kinetic modeling suggested that adsorption was governed by both physical partitioning and chemisorption mechanisms. In addition, microwave biochars maintained 79% to 92% of their initial adsorption capacity after ten adsorption/desorption cycles. These results suggest that microwave biochars produced with an GAC catalyst have excellent potential for efficient use in the removal of VOCs from waste gas.


Assuntos
Carvão Vegetal , Compostos Orgânicos Voláteis , Adsorção , Benzeno , Micro-Ondas
16.
Bioresour Technol ; 340: 125725, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34385129

RESUMO

A novel one-pot synthesis method was developed to prepare modified hydrochar by co-hydrothermal carbonization of waste distillers grains using low-cost clay minerals (attapulgite or vermiculite). The loading of the clay minerals onto hydrochar surfaces altered the structure and surface composition of the hydrochar such that the clay-modified hydrochars showed better ability to adsorb methylene blue and phosphate in aqueous solution than the pristine hydrochar. The maximum methylene blue and phosphate adsorption capacities of the modified hydrochar reached 340.3 and 96.9 mg g-1, respectively, comparable or higher than that of many commercial sorbents. Multiple mechanisms, including electrostatic attraction, ion exchange, complexation, and physical adsorption, controlled the adsorption process. These results highlight excellent potential for distillers grains-derived hydrochar-clay composites as an environmental sorbent, capable of removing a variety of contaminants from aqueous solutions.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Adsorção , Argila , Azul de Metileno/análise , Minerais , Fosfatos , Poluentes Químicos da Água/análise
17.
Sci Total Environ ; 783: 146983, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34088139

RESUMO

One-step synthesis of multifunctional materials using biomass waste for environmental remediation is a current research hotspot. In this study, a novel P-enriched hydrochar was obtained by co-hydrothermal treatment of biomass (bamboo or hickory) with concentrated H3PO4 (biomass: H3PO4 = 1:4) at 200 °C for 7 h. The characteristics of the P-enriched hydrochar were determined and its effect on the stabilization of Pb in soils was investigated. Compared to pristine hydrochar, the weight yield of the P-enriched hydrochar was greater (by over 2 times). This was due to the enrichment of P (over 20% by weight), as the C, N, and H weight content was reduced. Moreover, the aromaticity, thermal stability, and surface functionality of P-enriched hydrochar were all higher than that of pristine hydrochar. Addition of the pristine hydrochar to a simulated 1300 mg·kg-1 Pb-contaminated soil at 3% (w/w) resulted in a 20%-40% reduction in leached Pb only after 4 weeks, compared to the control without hydrochar amendment. However, addition of the P-enriched hydrochar to the spiked Pb-contaminated soil reduced Pb leaching by about 60% after only 1 week and about 90% after 3 weeks. Besides, using a real Pb-contaminated soil (149,000 mg·kg-1 Pb), P-enriched hydrochar addition at 5% (w/w) resulted in a 100% decrease in Pb leaching in the first week and maintained leached Pb levels at <2 mg L-1, meeting U.S.-E.P.A. standards. Thus, P-enriched hydrochar stabilized Pb in both simulated and real Pb-contaminated soil quickly and efficiently. Hence, the potential of one-step co-hydrothermal carbonization of biomass with H3PO4 to produce a novel and sustainable P-enriched hydrochar with properties suitable for environmental remediation of cationic metals.

18.
Bioresour Technol ; 337: 125432, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34171704

RESUMO

In this work, hickory chip biochars developed at distinctive pyrolysis temperatures were ball milled (BMHC) and then post-modified with a 10% hydrogen peroxide (H2O2) solution to obtain a set of novel sorbents (BMHC-H2O2). The specific surface area (SSA) was dramatically increased after ball-milling while the hydroxyl and carboxyl groups on the surface of the biochars were further increased through H2O2 modification. Additionally, thermal stability of the biochar treated with ball-milling was not greatly reduced by H2O2 modification and hydrodynamic radius was decreased. Ball milling enhanced the adsorption efficiency to methylene blue (MB) by the biochar, and this ability was further increased by H2O2 modification, because of the increasing in oxygen-containing functional groups (OCFG) to interact with MB. The rate of MB adsorption to BMHC-H2O2 was faster than that of BMHC, reaching equilibrium after about 6 h. Among adsorbents tested, the 450 °C BMHC-H2O2 had the greatest MB adsorption capacity (310 mg g-1).


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Peróxido de Hidrogênio , Poluentes Químicos da Água/análise
20.
Mol Autism ; 12(1): 38, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034808

RESUMO

BACKGROUND: Sulforaphane (SF), an isothiocyanate in broccoli, has potential benefits relevant to autism spectrum disorder (ASD) through its effects on several metabolic and immunologic pathways. Previous clinical trials of oral SF demonstrated positive clinical effects on behavior in young men and changes in urinary metabolomics in children with ASD. METHODS: We conducted a 15-week randomized parallel double-blind placebo-controlled clinical trial with 15-week open-label treatment and 6-week no-treatment extensions in 57 children, ages 3-12 years, with ASD over 36 weeks. Twenty-eight were assigned SF and 29 received placebo (PL). Clinical effects, safety and tolerability of SF were measured as were biomarkers to elucidate mechanisms of action of SF in ASD. RESULTS: Data from 22 children taking SF and 23 on PL were analyzed. Treatment effects on the primary outcome measure, the Ohio Autism Clinical Impressions Scale (OACIS), in the general level of autism were not significant between SF and PL groups at 7 and 15 weeks. The effect sizes on the OACIS were non-statistically significant but positive, suggesting a possible trend toward greater improvement in those on treatment with SF (Cohen's d 0.21; 95% CI - 0.46, 0.88 and 0.10; 95% CI - 0.52, 0.72, respectively). Both groups improved in all subscales when on SF during the open-label phase. Caregiver ratings on secondary outcome measures improved significantly on the Aberrant Behavior Checklist (ABC) at 15 weeks (Cohen's d - 0.96; 95% CI - 1.73, - 0.15), but not on the Social Responsiveness Scale-2 (SRS-2). Ratings on the ABC and SRS-2 improved with a non-randomized analysis of the length of exposure to SF, compared to the pre-treatment baseline (p < 0.001). There were significant changes with SF compared to PL in biomarkers of glutathione redox status, mitochondrial respiration, inflammatory markers and heat shock proteins. Clinical laboratory studies confirmed product safety. SF was very well tolerated and side effects of treatment, none serious, included rare insomnia, irritability and intolerance of the taste and smell. LIMITATIONS: The sample size was limited to 45 children with ASD and we did not impute missing data. We were unable to document significant changes in clinical assessments during clinical visits in those taking SF compared to PL. The clinical results were confounded by placebo effects during the open-label phase. CONCLUSIONS: SF led to small yet non-statistically significant changes in the total and all subscale scores of the primary outcome measure, while for secondary outcome measures, caregivers' assessments of children taking SF showed statistically significant improvements compared to those taking PL on the ABC but not the SRS-2. Clinical effects of SF were less notable in children compared to our previous trial of a SF-rich preparation in young men with ASD. Several of the effects of SF on biomarkers correlated to clinical improvements. SF was very well tolerated and safe and effective based on our secondary clinical measures. TRIAL REGISTRATION: This study was prospectively registered at clinicaltrials.gov (NCT02561481) on September 28, 2015. Funding was provided by the U.S. Department of Defense.


Assuntos
Transtorno do Espectro Autista , Transtorno do Espectro Autista/tratamento farmacológico , Criança , Pré-Escolar , Humanos , Isotiocianatos/efeitos adversos , Laboratórios Clínicos , Sulfóxidos , Estados Unidos
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