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1.
Eur J Med Chem ; 245(Pt 2): 114902, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36403514

RESUMO

A series of new pyrimidine thioethers, recognized as the key intermediates in the synthesis of S-DABO antivirals, were prepared and evaluated both in vivo and in silico. The purpose of this evaluation was to find novel structural analogues of the known antihypoxic drug Isothiobarbamine endowed with improved pharmacological profile. The in vivo studies led to the identification of compounds 5c, 5e, and 5f endowed with antidepressant/anxiolytic, performance enhancing, and nootropic properties. Compounds 5c and 5f were further tested in mice affected by social depression and were able to increase motor and tentative search activity compared to control groups, along with higher interaction frequency and better results in a sucrose preference test. Overall, these data suggested a better psychoemotional state of the animals, treated with compounds 5c, and 5f. Moreover, 5c and 5f exhibited minimal acute toxicity, lower than Fluoxetine hydrochloride. Molecular modelling studies finally indicated the plausible biomolecular mechanism of action of compounds 5c, 5e, and 5f, which seem to bind GABA-A, melatonin, and sigma-1 receptors. Moreover, three-dimensional structure-activity relationships enabled to define a SAR model that will be of great utility for the design of further structurally optimized compounds of the above mentioned chemotype.


Assuntos
Ansiolíticos , Nootrópicos , Animais , Camundongos , Ansiolíticos/farmacologia , Sulfetos , Antidepressivos/farmacologia , Pirimidinas
2.
Environ Res ; 216(Pt 3): 114627, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336095

RESUMO

Thallium (Tl) is a rare and extremely toxic metal whose toxicity is significantly higher than cadmium (Cd), lead (Pb) and antimony (Sb). The extensive utilization of Tl-bearing minerals, such as mining activities, has led to severe Tl pollution in a variety of natural settings, while little is known to date about its effect on the microbial diversity in paddy soils. Also, the geochemical behavior of Tl in the periodical alterations between dry and wet conditions of paddy soils remains largely unknown. Herein, the sequential extraction method and 16S rRNA gene sequence analysis were adopted to analyze Tl's migration and transformation behavior and the microbial diversity in the paddy soils with different pollution levels. The results indicated that Tl was mainly concentrated in reducible fraction, which is different from other types of soils, and may be closely attributed to the abundance of Fe-Mn (hydr)oxides in the paddy rhizospheric soils. Further analysis revealed that pH, total S, Pb, Sb, Tl and Cd were the dominant environmental factors, and the enrichment level of these potentially toxic metal(loid)s (PTMs) exerted obvious impacts on the diversity and abundance of microorganism in the rhizospheric soils, and regulating microbial community. The geochemical fractionation of Tl was closely correlated to soil microorganisms such as Fe reducing bacteria (Geothrix) and sulfate reducing bacteria (Anaerolinea), playing a critical role in Tl geochemical cycle through redox reaction. Hence, further study on microorganisms of paddy rhizospheric soils is of great significance to the countermeasures for remediating Tl-polluted paddy fields and protect the health of residents.


Assuntos
Poluentes do Solo , Tálio , Tálio/análise , Tálio/química , Tálio/toxicidade , Solo/química , Poluentes do Solo/análise , RNA Ribossômico 16S/genética , Cádmio/análise , Chumbo/análise , Sulfetos
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 284: 121783, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36081193

RESUMO

Herein, a novel fluorometric-sensor with dual-emission system was constructed on the basis of polyvinylpyrrolidone (PVP) and 2-mercaptobenzothiazole (MBT) co-functionalized gold/copper nanoclusters (PVP/MBT-Au@CuNCs) by a facile and eco-friendly one-pot approach. The sensor exhibited ratiometric fluorescence emission (F590 nm/F422 nm) for visual and selective detection of S2- with a sensitive detection limit of 11.9 nM. Besides, fluorescence quenched sensing of S2- was chalked up by a quickly selectivity monitoring time of 30 s, owing to the strongly binding of Cu2S and Au2S by hard-soft-acid-base theory and the destruction of the aggregated structure of PVP/MBT-Au@CuNCs. Furthermore, the platform also provided the portable analysis for visual detection of S2- by capturing the change in fluorescence color with a single dual-emissive ratiometric paper strip. It is worth mentioning that the fluorescent gold-copper nanoclusters showed excellent application activities in the selective detection of S2- in Radix Codonopsis or Tremella samples and recognition of S2- in HeLa cells or macrophages by confocal microscopy fluorescent imaging. Overall, the sensing system paved a new avenue for effectively developing a convenient ratiometric fluorescent sensor platform for evaluating the safety of food with S2- pollution in environment and biological system.


Assuntos
Codonopsis , Nanopartículas Metálicas , Cobre/análise , Corantes Fluorescentes/química , Ouro/química , Células HeLa , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Povidona , Espectrometria de Fluorescência/métodos , Sulfetos
4.
J Colloid Interface Sci ; 629(Pt A): 276-286, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36081207

RESUMO

S-scheme heterojunction structure can endow the photocatalysts with high-performance photo-degradation of pharmaceuticals and personal care products (PPCPs) since it can remain the photogenerated electrons/holes with stronger redox ability. Herein, an integrative S-scheme heterojunction photocatalyst building from Cd0.5Zn0.5S nanoparticles and BiOCl microflowers with oxygen vacancies (OVs) was developed. Moreover, the in-situ grown process ensures the firm contact and intense electron coupling between BiOCl and Cd0.5Zn0.5S. As a result, Cd0.5Zn0.5S/BiOCl exhibited a significant reinforcement of photo-activity and stability for the abatement of antibiotic norfloxacin, manifesting a 2.8-fold or 9.6-fold enhancement compared to pristine Cd0.5Zn0.5S or BiOCl. Cd0.5Zn0.5S/BiOCl also shows good resistance to alkaline, sodium salts and humic acid. The performance of Cd0.5Zn0.5S/BiOCl to photocatalytically degrade other PPCPs with different molecular structures was further confirmed. At last, the ability of Cd0.5Zn0.5S/BiOCl for PPCPs de-toxicity was verified by evaluating the toxicity of norfloxacin and its degradation intermediate. This study demonstrates a new S-scheme heterojunction photocatalyt for efficient removal of PPCPs as well as provides some insights into developing high-performance metal sulfide solid-solution-based S-scheme heterojunctions for water decontamination.


Assuntos
Cádmio , Norfloxacino , Fotólise , Antibacterianos/farmacologia , Antibacterianos/química , Catálise , Oxigênio , Substâncias Húmicas , Sais , Luz , Zinco , Sulfetos , Água , Preparações Farmacêuticas , Sódio
5.
J Colloid Interface Sci ; 629(Pt A): 399-408, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36088689

RESUMO

In vitro or in vivo fluorescence imaging based on quantum dots (QDs) has shown promise for the noninvasive diagnosis of atherosclerosis. However, simultaneous in vitro and in vivo imaging remains challenging due to the limitation of the current synthesis method of dual-emission QDs (dual-emitting hybrid QDs, and broad-spectrum emitting QDs). Herein, we fabricate a dual-emission (visible region and near-infrared region emission) QDs (ZAISe/ZnS) via the "bottom to up" method of a quaternary inorganic compound for the foam cells and atherosclerosis plaque imaging simultaneously without the intricate size modulation and the strict optical filter requirements. The oil-soluble ZAISe/ZnS is further encapsulated with bovine serum albumin (BSA) to realize phase transfer and ultimately possess the inflammation-targeting properties via biomimetic treatment with MMV (macrophage-derived micro-vesicle). The results first indicate that the as-constructed ZAISe/ZnS@BSA@MMV could accurately locate the foam cells and conduct long-term imaging of the atherosclerotic plaque, which provides a new strategy for the early and noninvasive diagnosis of atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Pontos Quânticos , Humanos , Soroalbumina Bovina , Células Espumosas , Placa Aterosclerótica/diagnóstico por imagem , Compostos de Zinco , Sulfetos , Aterosclerose/diagnóstico por imagem
6.
J Colloid Interface Sci ; 629(Pt A): 994-1002, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36152623

RESUMO

Metal sulfides are regarded as efficient scavengers for heavy metals. However, the heavy metal adsorption capacity of metal sulfides is far from its theoretical values due to the insufficient exposure of adsorption sites. Surface modification of metal sulfides is considered one of the most effective strategies for improving heavy metal removal performance. Here, microalgae-derived carbon quantum dots (CQDs) were used as a green modifier for mediating nano-MnS/FeS formation to enhance Cd2+ removal. With the addition of 1 wt% CQDs, the Cd2+ adsorption capacity of 1 %CQDs-MnS reached 481 mg/g at 25 °C and 648.6 mg/g at 45 °C, which surpassed most of the previously reported metal sulfides. Furthermore, the CQDs-modified MnS displayed a better Cd2+ removal capacity than the commercial modifier sodium alginate. The mechanism analysis suggested that decreasing the particle size to expose more adsorption sites and providing additional chelating sites derived from the CQDs are two main reasons why CQDs enhance the Cd2+ adsorption capacity of metal sulfides. This study presents an exceptional cadmium nano-adsorbent of 1 %CQDs-MnS and provides a new perspective on the enhancement of heavy metal removal by using CQDs as a promising and universal green modifier that mediates the formation of metal sulfides.


Assuntos
Metais Pesados , Microalgas , Pontos Quânticos , Cádmio , Carbono , Adsorção , Alginatos , Sulfetos
7.
Food Chem ; 402: 134313, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36155287

RESUMO

Food extrusion is mostly used for cereal processing. It is necessary to seek a novel technology to develop meat-based extrudates. This study investigated the physicochemical properties of extrudates consisting of 50% chicken and 50% Indica rice flour with different addition of NaHCO3 (0%, 0.25%, 0.50%) and moisture (12%, 14%, 16%). The largest expansion ratio occurred by 0.25% NaHCO3 addition. In the same moisture, the water solubility index increased first and then decreased, while the water absorption index increased with the increase of NaHCO3. With the increase of moisture, the hardness and crispiness of extrudates generally decreased regardless of the addition of NaHCO3. Importantly, at 14% moisture content, with NaHCO3 addition increasing, a more refined cellular structure occurred, sulfide compounds enhanced and the rate of Maillard reaction increased. Summarily, 0.25% NaHCO3 addition with 14% moisture content to assist extrusion had a tremendous potential to improve the quality of chicken-based extrudates.


Assuntos
Galinhas , Manipulação de Alimentos , Animais , Bicarbonato de Sódio/farmacologia , Água , Sulfetos
8.
J Hazard Mater ; 442: 130022, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36155303

RESUMO

Manganese oxides as common soil components were considered as an important sink for the cadmium pollution, which, however, would be affected by the reductive sulfide introduced during the flooding period of paddy soil. In this study, the phase transitions caused by the reactions among S2-, MnO2 and Cd2+ were visualized by atomic force microscopy (AFM). The dissolution of MnO2 was in-situ studied by AFM in the S2-containing environments. Moreover, in the ternary system (S2-, MnO2 and Cd2+), the pre-adsorption of Cd2+ by the MnO2 nanosheets would promote the subsequent precipitation of CdS on the surface of MnO2, while the pre-formed CdS nanoparticles in the aquatic phase would tend to suspense rather than precipitating on MnO2. The kinetic study results indicated that the CdS crystallite generation rate was faster than the MnO2 dissolution rate in the aquatic environments with different sulfide contents. In the macroscopic Cd2+ fixation test, the introduction of S2- dramatically improved the fixation of the pre-adsorbed Cd2+ on the MnO2 nanosheets by forming the CdS precipitate. This study provided a fundamental understanding of the interactions among the S2-, MnO2 and Cd2+ ternary system and shed light on the development of Cd pollution remediation methods for paddy soils.


Assuntos
Oryza , Poluentes do Solo , Compostos de Manganês , Cádmio , Óxidos , Manganês , Solo , Enxofre , Sulfetos
9.
J Colloid Interface Sci ; 630(Pt A): 921-930, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36306603

RESUMO

Ti-incorporated mesoporous materials have widespread applications in photocatalysis. Their adjustable pores could accommodate dyes like alizarin red S (ARS) to circumvent the lack of visible light response. Herein, Ti-MCM-41 was obtained to anchor visible light-capturing ARS, forming ARS-Ti-MCM-41. The ARS-Ti-MCM-41 was screened for the selective photocatalytic oxidation of organic sulfides. To improve the stability of the anchored ARS, electron transfer was orchestrated by a mediator trimethylamine (TMA, 2 mol%) illuminated by blue LEDs. Phenyl methyl sulfide could be almost entirely converted into phenyl methyl sulfoxide with 99% of selectivity within 18 min. In addition, Ti-MCM-41 was beneficial for the anchored ARS, which in turn guaranteed good recycling performance of ARS-Ti-MCM-41. The solvent trifluoroethanol enabled the stability of TMA and facilitated the highly selective formation of the target sulfoxides. This work sheds light on the vast possibility for visible light photocatalysis of dye-mesoporous materials.


Assuntos
Corantes , Sulfetos , Catálise , Titânio , Luz
10.
Chemosphere ; 310: 136747, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36216113

RESUMO

Dissolved heavy metals (DHMs) contamination has raised global concern for ecological and human health development. Weathering of sulfide-bearing ore metals can produce acidic, sulfate-rich solutions in the presence of water and oxygen (O2), and DHMs are released to deprave the river water quality. Sulfur and oxygen isotope signatures (δ34SSO4 and δ18OSO4) could identify this pyrite-derived sulfate; however, it is yet not well known whether the δ34SSO4 and δ18OSO4 values could limit the DHMs sources and illustrate anthropogenic impacts on DHMs along the river corridor. We tried to solve this problem through field works in the Luohe River and Yihe River, two tributaries of the Yellow River, China, where metal sulfide mine activities mostly occurred upstream, but agricultural and domestic behaviors concentrated in the lower plain reaches. In the Luohe River upper areas, δ34SSO4 values had negative correlations with concentrations of cadmium (Cd) (p < 0.01), nickel (Ni) (p < 0.05), molybdenum (Mo) (p < 0.01), uranium (U) (p < 0.01), and SO42- (p < 0.01). However, as the δ34SSO4 values increased downstream in the Luohe River, concentrations of copper (Cu) (p < 0.05), mercury (Hg) (p < 0.05), Ni (p < 0.05), and SO42- (p < 0.01) simultaneously elevated. The Bayesian Isotope Mixing Model (BIMM) results via δ34SSO4 values demonstrated 64.3%-65.3% of SO42- from acid mine drainage (AMD) in the Luohe River's upper reaches and 63.5%-67.7% in the Yihe River's upper reaches, and about 33% from sewage and industrial effluents in the Luohe River's lower reaches and 27% in Yihe River's lower reaches. Our results confirmed the different anthropogenic impacts on the DHMs concentrations in Luohe River and Yihe River and provided a robust method for DHMs sources appointment and pollution management in river systems.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Teorema de Bayes , Efeitos Antropogênicos , Metais Pesados/análise , Sulfatos/análise , Isótopos de Oxigênio/análise , Sulfetos , China
11.
Sci Total Environ ; 855: 158870, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36155048

RESUMO

Hydrometallurgical processing of electronic waste produces copper (Cu)-containing wastewater. Recycling of Cu is thus crucial, as it reduces the Cu impact on the environment, and increases Cu sustainability in industry. Vacuum distillation provides excellent performance in both metals removal from aqueous solution, metal recovery, and metal impregnation to porous material. Thus, this work aimed to both utilize a vacuum distillation to remove heavy metals (Cu, Na, Ni, Zn and Fe) and recover copper nitrate hydroxide (Cu2NO3(OH)3) from Cu-containing wastewater in industrial applications (e.g., mordant agent in dyeing and pigment for glass), as well as prepare copper sulfide (CuS) impregnated activated carbon for mercury (Hg0) adsorption. The experimental results indicated a vacuum distillation metals removal efficiency of over 99.99 % at 60 °C and -72 cm Hg. Additionally, the copper nitrate hydroxide (Cu2NO3(OH)3) crystalline solid derived from the vacuum distillation process achieved 77 % purity, and the copper sulfide impregnated activated carbon (CuSAC) adsorbents were prepared by adding activated carbon (AC) during the vacuum distillation process. In adsorption tests, 50 % CuSAC exhibited the greatest gaseous mercury (Hg0) adsorption performance, and it was noted that a high adsorption temperature of 175 °C negatively impacted Hg0 adsorption of 50 % CuSAC due to mercury sulfide (HgS) decomposition. Furthermore, in a simulated flue gas (SFG) environment, Hg0 capture by CuSAC was shown to be slightly obstructed. In addition, mercury temperature-programmed desorption (Hg-TPD) identified that HgS was the dominant species among adsorbed Hg species of Hg-laden 50 % CuSAC, indicating that Hg0 capture of CuSAC was mainly facilitated by sulfur active sites. As such, the vacuum distillation technique proved to efficiently remove metals and leads to successful preparation of adsorbent for Hg. Therefore, the process is an effective treatment method for Cu-containing wastewater, and can be practically applied to capture or recycle Cu in the industry in the future.


Assuntos
Mercúrio , Metais Pesados , Mercúrio/análise , Adsorção , Carvão Vegetal , Águas Residuárias , Gases , Cobre , Nitratos , Destilação , Vácuo , Sulfetos , Hidróxidos
12.
Sci Total Environ ; 856(Pt 1): 158839, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36155030

RESUMO

Bio-cathode Microbial electrolysis cell (MEC) has been widely discovered for heavy metals removal and hydrogen production. However, low electron transfer efficiency and heavy metal toxicity limit MEC treatment efficiency. In this study, ZIF-67 was introduced to modify Sulfate-reducing bacteria (SRB) bio-cathode to enhance the bioreduction of sulfate and Antimony (Sb) with hydrogen production in the MEC. ZIF-67 modified bio-cathode was developed from a bio-anode microbial fuel cell (MFC) by operating with an applied voltage of 0.8 V to reverse the polarity. Cyclic voltammetry, linear sweep voltammetry and electrochemical impedance were done to confirm the performance of the ZIF-67 modified SRB bio-cathode. The synergy reduction of sulfate and Sb was accomplished by sulfide metal precipitation reaction from SRB itself. Maximum sulfate reduction rate approached 93.37 % and Sb removal efficiency could reach 92 %, which relies on the amount of sulfide concentration generated by sulfate reduction reaction, with 0.923 ± 0.04 m3 H2/m3 of hydrogen before adding Sb and 0.857 m3 H2/m3 of hydrogen after adding Sb. The hydrogen was mainly produced in this system and the result of gas chromatography (GC) indicated that 73.27 % of hydrogen was produced. Meanwhile the precipitates were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy to confirm Sb2S3 was generated from Sb (V).


Assuntos
Fontes de Energia Bioelétrica , Desulfovibrio , Metais Pesados , Eletrólise/métodos , Eletrodos , Fontes de Energia Bioelétrica/microbiologia , Sulfatos/química , Hidrogênio/química , Sulfetos/química
13.
Sci Total Environ ; 855: 158913, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36411604

RESUMO

The sewer system is a significant source of hydrogen sulfide (H2S) and greenhouse gases which has attracted extensive interest from researchers. In this study, a novel combined dosing strategy using nitrate and calcium peroxide (CaO2) was proposed to simultaneously control sulfide and greenhouse gases, and its performance was evaluated in laboratory-scale reactors. Results suggested that the addition of nitrate and CaO2 improved the effectiveness of sulfide control. And the combination index method further proved that nitrate and CaO2 were synergistic in controlling sulfide. Meanwhile, the combination of nitrate and CaO2 substantially reduced greenhouse gas emissions, especially the carbon dioxide (CO2) and methane (CH4). The microbial analysis revealed that the combined addition greatly stimulated the accumulation of nitrate reducing-sulfide oxidizing bacteria (NR-SOB) that participate in anoxic nitrate-dependent sulfide oxidation, while the abundance of heterotrophic denitrification bacteria (hNRB) was reduced significantly. Moreover, the presence of oxygen and alkaline chemicals generated by CaO2 facilitated the inhibition of sulfate-reducing bacteria (SRB) activities. Therefore, the nitrate dosage was diminished significantly. On the other hand, the generated alkaline chemicals promoted CO2 elimination and inhibited the activities of methanogens, leading to a decrease of CO2 and CH4 fluxes, which facilitated elimination of greenhouse effects. The intermittent dosing test showed that the nitrate and CaO2 could be applied intermittently for sulfide removal. And the chemical cost of intermittent dosing strategy was reduced by 85 % compared to the continuous dosing nitrate strategy. Therefore, intermittent dosing nitrate combined with CaO2 is probably an effective and economical approach to control sulfide and greenhouse gases in sewer systems.


Assuntos
Gases de Efeito Estufa , Nitratos , Esgotos/microbiologia , Dióxido de Carbono , Oxirredução , Sulfetos , Óxidos de Nitrogênio
14.
Sci Total Environ ; 856(Pt 2): 159142, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36183767

RESUMO

Acid sulfate soils discharge large amounts of sulfuric acid along with toxic metals, deteriorating water quality and ecosystem health of recipient waterbodies. There is thus an urgent need to develop cost-effective and sustainable measures to mitigate the negative effects of these soils. In this study, we flushed aseptically-prepared MQ water (reference) or mitigation suspensions containing calcite, peat or a combination of both through 15-cm-thick soil cores from an acid sulfate soil field in western Finland, and investigated the geochemistry of Fe and S on the surfaces of macropores and in the solid columnar blocks (interiors) of the soil columns. The macropore surfaces of all soil columns were strongly enriched in total and HCl-extractable Fe and S relative to the interiors, owing to the existence of abundant Fe oxyhydroxysulfates (schwertmannite and partly jarosite) as yellow-to-brownish surface-coatings. The dissolution/hydrolysis of Fe oxyhydroxysulfates (predominantly jarosite) on the macropore surfaces of the reference columns, although being constantly flushed, effectively buffered the permeates at pH close to 4. These results suggest that Fe oxyhydroxysulfates accumulated on the macropore surfaces of boreal acid sulfate soils can act as long-lasting acidification sources. The treatments with mitigation suspensions led to a (near-)complete conversion of jarosite to Fe hydroxides, causing a substantial loss of S. In contrast, we did not observe any recognizable evidence indicating transformation of schwertmannite. However, sulfate sorbed by this mineral might be partially lost through anion-exchange processes during the treatments with calcite. No Fe sulfides were found in the peat-treated columns. Since Fe sulfides can support renewed acidification events, the moderate mineralogical changes induced by peat are desirable. In addition, peat materials can act as toxic-metal scavengers. Thus, the peat materials used here, which is relatively cheap in the boreal zone, is ideal for remediating boreal acid sulfate soils and other similar jarosite-bearing soils.


Assuntos
Ferro , Solo , Ferro/análise , Carbonato de Cálcio , Ecossistema , Sulfatos , Enxofre , Ácidos , Sulfetos
15.
J Environ Manage ; 325(Pt B): 116495, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36279773

RESUMO

pH is notably known as the main variable defining distinct metabolic pathways during sugarcane vinasse dark fermentation. However, different alkalinizing (e.g. sodium bicarbonate; NaHCO3) and/or neutralizing (e.g. sodium hydroxide; NaOH) approaches were never directly compared to understand the associated impacts on metabolite profiles. Three anaerobic structured-bed reactors (AnSTBR) were operated in parallel and subjected to equivalent operational parameters, except for the pH control: an acidogenic-sulfidogenic (R1; NaOH + NaHCO3) designed to remove sulfur compounds (sulfate and sulfide), a hydrogenogenic (R2; NaOH) aimed to optimize biohydrogen (bioH2) production, and a strictly fermentative system without pH adjustment (R3) to mainly evaluate lactic acid (HLa) production and other soluble metabolites. NaHCO3 dosing triggered advantages not only for sulfate reduction (up to 56%), but also to enhance the stripping of sulfide to the gas phase (75-96% of the theoretical sulfide produced) by the high and constant biogas flow resulting from the CO2 released during NaHCO3 dissociation. Meanwhile, molasses-based vinasse presented higher potential for bioH2 (up to 4545 mL-H2 L-1 d-1) and HLa (up to 4800 mg L-1) production by butyric-type and capnophilic lactic fermentation pathways. Finally, heterolactic fermentation was the main metabolic route established when no pH control was provided (R3), as indicated by the high production of both HLa (up to 4315 mg L-1) and ethanol (1987 mg L-1). Hence, one single substrate (from which one single source of inoculum was originated) offers a wide range of metabolic possibilities to be exploited, providing substantial versatility to the application of anaerobic digestion in sugarcane biorefineries.


Assuntos
Saccharum , Fermentação , Saccharum/química , Hidrogênio , Hidróxido de Sódio , Sulfatos , Sulfetos , Reatores Biológicos
16.
Chemosphere ; 311(Pt 1): 136956, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36280119

RESUMO

Reductive dissolution of scorodite results in the release and migration of arsenic (As) in groundwater. The purpose of this study was to explore the possible abiotic and biotic reduction of scorodite in groundwater environment and the effect of microbial-mediated sulfur cycling on the bio-reduction of scorodite. Microcosm experiments consisting of scorodite with bacterium Citrobacter sp. JH012-1 or free sulfide were carried out to determine the effects of thiosulfate on the mobilization of As/Fe. The results show arsenic release is positively correlated with iron reduction. The arsenate [As(V)] released can agglomerate with Fe(II) on the surface of scorodite to form crystalline parasymplesite, while no parasymplesite was detected in the abiotic reduction of scorodite by sulfide. The reduction of scorodite and As(V) was affected by thiosulfate. When 0.5 mM thiosulfate was added, the Fe(III) reduction rate increased from 32% to 82%, and the As(V) reduction rate rose from 54% to 64%. When the addition of thiosulfate was increased from 0.5 mM to 2 mM and 5 mM, Fe(III) reduction rate added 4% and 8%, and As(V) reduction rate increased 11% and 16%, respectively. In addition, the presence of thiosulfate promoted the scorodite almost completely converting to parasymplesite. Therefore, the effect of microbial-mediated sulfur cycling should be considered in arsenic migration and reduction from scorodite.


Assuntos
Arsênio , Água Subterrânea , Arsênio/química , Tiossulfatos/metabolismo , Compostos Férricos/química , Oxirredução , Água Subterrânea/química , Bactérias/metabolismo , Sulfetos/metabolismo , Enxofre/metabolismo
17.
J Environ Manage ; 325(Pt B): 116588, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36308954

RESUMO

Nowadays, groundwater quality has deteriorated because of intensive human activities. It is important to accurately identify the pollution source for controlling the deterioration of groundwater quality. However, the accuracy of the current source analysis method needs to be improved. In this study, we combined hydrochemical method, isotope tracing technique and PMF model, for the first time, to trace the source of groundwater pollution in Beichuan River basin, Qinghai Province, China. According to the results, there were 35.8% of Fe, 34.1% of total hardness, 24.3% of SO42- and 8.09% of NO3- samples exceeded the Grade III standards for Groundwater quality in China, which indicated that the groundwater in the study area has been significantly affected by human activities. Hydrochemical method suggested that the chemical component originated from rock weathering, cation exchange and mineral dissolution. Based on isotope tracing technique (δ15N-NO3-, δ18O-NO3-, δ34S-SO42- and δ18O-SO42-), the primary sources of nitrate and sulfate in groundwater were soil nitrogen and oxidation of sulfide minerals in the forest area, domestic sewage and oxidation of sulfide minerals in the urban and industrial area, and mixed sources in the village and agricultural area. Finally, the pollution source of groundwater was distinguished by combining the PMF model, isotope tracing technique and hydrochemical method. Results showed that the main pollutant of groundwater is domestic sewage in the urban, village and industrial area. The contribution rates to groundwater pollution were 60.7%, 60.8% and 57.8%, respectively. However, in the forest and agricultural area, the main source changed to water-rock interaction and chemical fertilizer, and the contribution rates to groundwater quality were 53.5% and 61.0%, respectively. Our results suggested that the coupling tracing methodology can improve the accuracy of source resolution in the water environment and it can be applied to other areas of the world.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Esgotos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Isótopos de Nitrogênio/análise , Nitratos/análise , Sulfetos/análise , Água/análise , China
18.
J Colloid Interface Sci ; 630(Pt B): 460-472, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334483

RESUMO

The build-in electric field by the construction of heterojunction is one of the most promising strategies to suppress the recombination of photogenerated carriers. Here, we reported a piezo-photocatalytic system composed of Se-decorated CdS nanowires and few-layered edge-on MoSe2 nanosheets for efficient H2 generation by two-pot hydrothermal synthesis. The few-layered MoSe2 exposed abundant edge sites for hydrogen evolution reaction (HER). The activity of 20-MoSe2/CdS0.95Se0.05 (20-MS/CSS, with 20 mol% of MoSe2 loading) nanocomposite casted a remarkable photocatalytic HER performance, with a rate of 47.3 mmol h-1 g-1. Moreover, MoSe2 nanosheets deformed to generate the piezoelectric polarization field under magnetic stirring, which rendered efficient separation of photogenerated carriers, resulting in a piezo-photocatalytic synergistic effect. As a result, the HER of 20-MS/CSS at 900 rpm for piezo-photocatalysis was 59.1 mmol h-1 g-1, which was 1.25 times that of 20-MS/CSS for photocatalysis. Meanwhile, the photoelectrochemical measurements further visualized the piezo-photoelectric synergy. This study exposes a new way for utilizing mechanical energy to improve photocatalytic performance, and achieving high piezo-photocatalysis.


Assuntos
Hidrogênio , Nanofios , Hidrogênio/química , Sulfetos/química , Processos Fotoquímicos , Catálise
19.
J Colloid Interface Sci ; 630(Pt B): 511-522, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36334487

RESUMO

Diseases caused by bacterial infection are becoming a major threat to human health. Therefore, developing efficient antibacterial materials is of great significance in improving medical care and protecting people's health. In this work, an accordion-like structural Ti3C2@CuS was synthesized by copper sulfide (CuS) nanospheres anchored firmly on the surface of Ti3C2Tx via the hydrothermal method. The multilayer Ti3C2@CuS becomes few-layered nanosheets after ultrasonic treatment, which have an enjoyable dispersion in the polyurethane (PU) matrix. PU and the released Cu2+ from Ti3C2@CuS are firmly linked by a coordination bond, which improves the mechanical properties and thermal stability of Ti3C2@CuS-PU and reduces the heavy metal ion pollution by blocking the Cu2+ released by forming coordination bonds. Moreover, Ti3C2@CuS-PU exhibits an excellent self-healing performance after 30 tensile cycles. Additionally, Ti3C2Tx and CuS could improve the separation efficiency of the electron-hole pairs of CuS to produce more reactive oxygen species (ROS) to kill bacteria. Ti3C2@CuS-PU maintains a highly long-term sterilization ability of more than 90 % in 30 days because of the synergistic effect of the sustained release of copper ions, the elevated ROS production ability, and the excellent dispersion of Ti3C2@CuS in PU. This work demonstrates a simple and promising route for designing multifunctional antibacterial self-healing materials.


Assuntos
Cobre , Poliuretanos , Humanos , Cobre/farmacologia , Cobre/química , Poliuretanos/farmacologia , Espécies Reativas de Oxigênio , Antibacterianos/farmacologia , Antibacterianos/química , Sulfetos
20.
Sci Total Environ ; 857(Pt 2): 159465, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36257419

RESUMO

Swampy/septic odor caused by thioethers has become the main taste and odor (T&O) problem in drinking water of China. Improving its removal performance by commonly traditional water treatment process is significant. In our study, we have found that pre-oxidation could modify the background dissolved organic matter (DOM) properties and thus improve the coagulation performance of thioethers, increasing the coagulation removal rates by 1.5-3 times. Particularly, after pre-ozonation only protein-like substances remained, and thioethers removal was 1.5 times higher than that after pre-chlorination (only coagulation not including oxidation). Compared with humic acid (HA), the thioethers compounds removal efficiencies under bovine serum albumin (BSA) as background DOM was increased by 0.3-3 times. Through Freundlich model analysis, the binding strength of BSA (KF = 20.712, at 298 K) to dimethyl disulfide (DMDS) was enhanced by 60 % compared to HA (KF = 12.778, at 298 K). According to thermodynamic parameters, the binding effect between HA/BSA and thioethers compounds was mainly van der Waals forces and hydrogen bond. BSA with more amino structure and oxygen groups was more easily to adsorb DMDS through hydrogen bond and thus achieved better coagulation performance. Therefore, pre-ozonation combined with coagulation was suggested to be more suitable for thioethers compounds control.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Sulfetos , Substâncias Húmicas/análise , Oxirredução , Ozônio/análise , Poluentes Químicos da Água/análise
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