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1.
Front Plant Sci ; 15: 1397686, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957607

RESUMO

The artificial cultivation and management were extensively carried out in Dendrocalamus brandisii stands. However, the influences of artificial management on the anatomical and chemical characteristics of the bamboo culms were unknown. In this study, the fiber morphology, chemical composition and sugar accumulation of the D. brandisii culms with management and without management were compared in order to determine the influences of artificial management on bamboo culms. The results indicated that artificial management had a significant influence on the fiber morphology, resulting in shorter fiber length, larger L/T ratio, and smaller W/Lu value. However, the management not only increased the contents of moisture, ash, SiO2, and extractive, but also increased the holocellulose contents and decreased the lignin contents, as compared to those without management. Moreover, the management significantly increased the endogenous carbohydrates storage in the culms so as to improve the shoot production. The bamboos under management conditions could still be utilized as a raw material for papermaking. This provided a theoretical basis for the artificial management of D. brandisii stands.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39007296

RESUMO

Tetracycline (TC) and Cu(II) coexist commonly in various waters, which may infiltrate into the subterranean environment through runoff and leaching, resulting in substantial ecological risks. However, the underlying mechanisms why Cu(II) affects the transport of TC in porous media remain to be further explored and supported by more evidence, especially the role of complexation. In this study, the transport of TC with coexisting Cu(II) was comprehensively explored with column experiments and density functional theory (DFT) calculation. At natural environmental concentrations, Cu(II) significantly inhibited the transport of TC in the quartz sand column. Cu(II) augmented the retention of TC in the column mainly via electrostatic force and complexation. The interaction between TC and TC-Cu complexes on the surface of SiO2 was investigated with first-principles calculations for the first time. There were strong van der Waals forces and coordination bonds on the surface of complexes and SiO2, leading to higher adsorption energy than that of TC and inhibiting its penetration. This study offers novel insights and theoretical framework for the transport of antibiotics in the presence of metal ions to better understand the fate of antibiotics in nature.

3.
J Environ Manage ; 366: 121714, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032253

RESUMO

Antibiotic shock may potentially impact the performance of promising microalgae-nitrifying bacteria consortia (MNBC) processes. This study investigated physiological behaviors of MNBC under sulfamethoxazole (SMX) shock (mg/L level) and verified a light regulating strategy for improving process performance. Results showed that SMX shock did not affect ammonium removal but caused nitrite accumulation, resulting from combined effects of excessive reactive oxidative species (ROS) production, inhibited microalgal photosynthetic activity, upregulated expressions of amoA and hao, and downregulated expression of nxrA. Moreover, high ammonium concentration aggravated nitrite accumulation and reduced ammonium removal owing to significantly reduced dissolved oxygen (DO). Increasing light intensity enhanced microalgal photo-oxygenation and promoted expressions of all nitrification-related genes, thus improving ammonium removal and alleviating nitrite accumulation. A central composite design coupled with response surface methodology (CCD-RSM) further demonstrated the negative impacts of SMX shock and high ammonium on MNBC and the effectiveness of the light regulation in maintaining stable process performance. This study provides theoretical basis for physiological responses and regulatory strategy of the MNBC process facing short-term antibiotic shock.

5.
Appl Environ Microbiol ; 90(7): e0089024, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38940564

RESUMO

Biological valorization of lignin, the second most abundant biopolymer on Earth, is an indispensable sector to build a circular economy and net-zero future. However, lignin is recalcitrant to bioupcycling, demanding innovative solutions. We report here the biological valorization of lignin-derived aromatic carbon to value-added chemicals without requesting extra organic carbon and freshwater via reprogramming the marine Roseobacter clade bacterium Roseovarius nubinhibens. We discovered the unusual advantages of this strain for the oxidation of lignin monomers and implemented a CRISPR interference (CRISPRi) system with the lacI-Ptrc inducible module, nuclease-deactivated Cas9, and programmable gRNAs. This is the first CRISPR-based regulatory system in R. nubinhibens, enabling precise and efficient repression of genes of interest. By deploying the customized CRISPRi, we reprogrammed the carbon flux from a lignin monomer, 4-hydroxybenzoate, to achieve the maximum production of protocatechuate, a pharmaceutical compound with antibacterial, antioxidant, and anticancer properties, with minimal carbon to maintain cell growth and drive biocatalysis. As a result, we achieved a 4.89-fold increase in protocatechuate yield with a dual-targeting CRISPRi system, and the system was demonstrated with real seawater. Our work underscores the power of CRISPRi in exploiting novel microbial chassis and will accelerate the development of marine synthetic biology. Meanwhile, the introduction of a new-to-the-field lineage of marine bacteria unveils the potential of blue biotechnology leveraging resources from the ocean.IMPORTANCEOne often overlooked sector in carbon-conservative biotechnology is the water resource that sustains these enabling technologies. Similar to the "food-versus-fuel" debate, the competition of freshwater between human demands and bioproduction is another controversial issue, especially under global water scarcity. Here, we bring a new-to-the-field lineage of marine bacteria with unusual advantages to the stage of engineering biology for simultaneous carbon and water conservation. We report the valorization of lignin monomers to pharmaceutical compounds without requesting extra organic substrate (e.g., glucose) or freshwater by reprogramming the marine bacterium Roseovarius nubinhibens with a multiplex CRISPR interference system. Beyond the blue lignin valorization, we present a proof-of-principle of leveraging marine bacteria and engineering biology for a sustainable future.


Assuntos
Lignina , Lignina/metabolismo , Engenharia Metabólica , Água do Mar/microbiologia , Sistemas CRISPR-Cas , Rhodobacteraceae/genética , Rhodobacteraceae/metabolismo
6.
Sci Total Environ ; 943: 173709, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38852864

RESUMO

Antibiotics and polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants in the aquatic region encompassing the estuary of the Yellow River and Laizhou Bay. But little information is available about the trophic transfer of antibiotics and PAHs in the marine food web of this area. This study investigated the occurrence and trophic transfer of 19 antibiotics and 16 PAHs in marine organisms from a food web of Laizhou Bay of the Yellow River estuary. Sulfonamides, fluoroquinolones, and 2 to 4-ring PAHs were the dominant contaminants in organisms. There was a significant positive correlation between the log total concentration of sulfonamides and trophic level (TL). Sulfadiazine, sulfamethazine, and erythromycin had biomagnification effects, while ciprofloxacin and ofloxacin had biological dilution effects. The log total concentration of PAHs had a significant negative correlation with TL. Naphthalene, fluorene, anthracene, pyrene, and benzo[g,h,i]perylene had biological dilution effects. The distinct correlations of trophic magnification factors Dow of antibiotics and Kow of 2 to 5-ring PAHs, indicating that the potential of these two coefficients for predicting their transfer. Risk assessment indicated that the consumption of seafood containing antibiotics and PAHs in Laizhou Bay of the Yellow River estuary posed health and carcinogenic risks to human, respectively.


Assuntos
Antibacterianos , Monitoramento Ambiental , Estuários , Cadeia Alimentar , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Antibacterianos/análise , China , Medição de Risco , Humanos , Rios/química , Organismos Aquáticos , Animais
7.
J Environ Manage ; 359: 121009, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38718600

RESUMO

Nitrification-denitrification process has failed to meet wastewater treatment standards. The completely autotrophic nitrite removal (CANON) process has a huge advantage in the field of low carbon/nitrogen wastewater nitrogen removal. However, slow start-up and system instability limit its applications. In this study, the time of the start-up CANON process was reduced by using bio-rope as loading materials. The establishing of graded dissolved oxygen improved the stability of the CANON process and enhanced the stratification effect between functional microorganisms. Microbial community structure and the abundance of nitrogen removal functional genes are also analyzed. The results showed that the CANON process was initiated within 75 days in the complete absence of anaerobic ammonium oxidizing bacteria (AnAOB) inoculation. The ammonium and nitrogen removal efficiencies of CANON process reached to 94.45% and 80.76% respectively. The results also showed that the relative abundance of nitrogen removal bacterial in the biofilm gradually increases with the dissolved oxygen content in the solution decreases. In contrast, the relative abundance of ammonia oxidizing bacteria was positively correlated with the dissolved oxygen content in the solution. The relative abundance of g__Candidatus_Brocadia in biofilm was 15.56%, and while g__Nitrosomonas was just 0.6613%. Metagenomic analysis showed that g__Candidatus_Brocadia also contributes 66.37% to the partial-nitrification functional gene Hao (K10535). This study presented a new idea for the cooperation between partial-nitrification and anammox, which improved the nitrogen removal system stability.


Assuntos
Processos Autotróficos , Nitritos , Nitrogênio , Águas Residuárias , Nitrogênio/metabolismo , Nitritos/metabolismo , Nitrificação , Desnitrificação , Bactérias/metabolismo , Bactérias/genética , Eliminação de Resíduos Líquidos/métodos , Biofilmes , Reatores Biológicos , Compostos de Amônio/metabolismo
8.
Cardiovasc Diabetol ; 23(1): 173, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762473

RESUMO

BACKGROUND: Insulin resistance (IR) significantly contributes to cardiovascular disease (CVD) development. Triglyceride glucose (TyG) index and triglyceride glucose-body mass index (TyG-BMI) are recognised as convenient proxies for IR. However, their relationship with sudden cardiac arrest (SCA) remains unclear. METHODS: This prospective cohort analysis included 355,242 UK Biobank participants with available TyG index and TyG-BMI data and no history of CVD. Cox proportional risk models assessed the association between the TyG index, TyG-BMI and SCA risk. Additionally, Accelerated Failure Time (AFT) models were employed to investigate the timing of SCA onset. The impact of dynamic increases in TyG index and TyG-BMI levels on SCA risk was examined using restricted cubic spline. RESULTS: Over a median follow-up period of 165.4 months (interquartile range 156.5-174 months), 1,622 cases of SCA were recorded. Multivariate Cox regression analysis revealed a 9% increase in SCA risk per standard deviation increase in TyG index (adjusted hazard ratio (aHR) = 1.09, 95% confidence interval (CI) 1.04-1.15) and an 14% increase per standard deviation increase in TyG-BMI (aHR 1.14, 95% CI 1.09-1.2). AFT models indicated earlier median times to SCA occurrence with increasing quintiles of TyG index and TyG-BMI compared to the lowest quintile (P for trend < 0.05). SCA risk was linearly (P = 0.54) and non-linearly (P = 0.007) correlated with gradual increases in TyG index and TyG-BMI levels, respectively. Sex-stratified analyses showed stronger associations in women. CONCLUSIONS: Higher TyG index and TyG-BMI levels are associated with an increased SCA risk and earlier onset, particularly in women.


Assuntos
Biomarcadores , Glicemia , Índice de Massa Corporal , Morte Súbita Cardíaca , Resistência à Insulina , Triglicerídeos , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Estudos Prospectivos , Glicemia/metabolismo , Medição de Risco , Idoso , Fatores de Tempo , Morte Súbita Cardíaca/epidemiologia , Biomarcadores/sangue , Adulto , Fatores de Risco , Reino Unido/epidemiologia , Prognóstico
9.
J Colloid Interface Sci ; 666: 585-593, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613980

RESUMO

Capacitive deionization (CDI) is flourishing as an energy-efficient and cost-effective water desalination method. However, challenges such as electrode degradation and fouling have hindered the practical deployment of CDI technology. To address these challenges, the key point of our strategy is applying a hydrophilic coating composed of polyethylene glycol (PEG)-functionalized nano-TiO2/polyvinylidene fluoride (PVDF) to the electrode interface (labeled as APPT electrode). The PEG/PVDF/TiO2 layer not only mitigates the co-ion depletion, but also imparts the activated carbon (AC) electrode hydrophilicity. As anticipated, the APPT electrode possessed an enhanced desalination capacity of 83.54 µmol g-1 and a low energy consumption of 17.99 Wh m-3 in 10 mM sodium chloride solution compared with the bare AC electrode. Notably, the APPT maintained about 93.19 % of its desalination capacity after 50 consecutive adsorption-desorption cycles in the presence of bovine serum albumin (BSA). During the trial, moreover, no obvious overall performance decline was noted in concentration reduction (Δc), water recovery (WR) and productivity (P) over 50 cycles. This strategy realizes energy-efficient, antifouling and stable brackish water desalination and has great promise for practical applications.

10.
Bioresour Technol ; 401: 130752, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685514

RESUMO

Oxygenic photogranules (OPGs) are currently obtained in permanent famine or cyclic feast-famine regimes. Whether photogranulation occurs under a permanent feast regime and how these regimes impact OPGs are unknown. Herein, the three regimes, each applied in two replicate hydrodynamic reactors, were established by different feeding frequencies. Results showed that OPGs were successfully cultivated in all regimes after 24-36 days of photogranulation phases with similar microbial community functions, including filamentous gliding, extracellular polymeric substances production, and carbon/nitrogen metabolism. The OPGs were then operated under the same sequencing batch mode and all achieved efficient removal of chemical oxygen demand (>91 %), ammonium (>96 %), and total nitrogen (>76 %) after different adaptation periods (19-41 days). Notably, the permanent feast regime obtained OPGs with the best physicochemical properties, the shortest adaptation period, and the lowest effluent turbidity, thus representing a novel means of hydrodynamic cultivating OPGs with better performances for sustainable wastewater treatment.


Assuntos
Hidrodinâmica , Nitrogênio , Oxigênio , Oxigênio/metabolismo , Reatores Biológicos , Análise da Demanda Biológica de Oxigênio , Águas Residuárias/química , Carbono/química , Purificação da Água/métodos
11.
J Hazard Mater ; 471: 134384, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38663292

RESUMO

Addressing the challenge of accurately monitoring polycyclic aromatic hydrocarbons (PAHs) in aquatic systems, this study employed diffusive gradients in thin-films (DGT) technique to achieve methods detection limits as low as 0.02 ng L-1 to 0.05 ng L-1 through in situ preconcentration and determination of time-integrated concentrations. The efficacy of the developed DGT samplers was validated under diverse environmental conditions, demonstrating independence from factors such as pH (5.03-9.01), dissolved organic matter (0-20 mg L-1), and ionic strength (0.0001-0.6 M). Notably, the introduction of a novel theoretical approach to calculate diffusion coefficients based on solvent-accessible volume tailored for PAHs significantly enhanced the method's applicability, particularly for organic pollutants with low solubility. Field deployments in coastal zones validated the DGT method against traditional grab sampling, with findings advocating a 4 to 7-day optimal deployment duration for balancing sensitivity and mitigating lag time effects. These results provide a sophisticated, efficient solution to the persistent challenge of monitoring hydrophobic organic pollutants in aquatic environments, broadening the scope and applicability of DGT in environmental science and providing a robust tool for researchers.

12.
Chemosphere ; 357: 141894, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615958

RESUMO

Given the presence of emerging pollutants at low concentrations in water bodies, which are inevitably affected by background substances during the removal process. In this study, we synthesized molecularly imprinted catalysts (Cu/Ni-MOFs@MIP) based on bimetallic metal-organic frameworks for the targeted degradation of ciprofloxacin (CIP) in advanced oxidation processes (AOPs). The electrostatic interaction and functional group binding of CIP with specific recognition sites on Cu/Ni-MOFs@MIP produced excellent selective recognition (Qmax was 14.82 mg g-1), which enabled the active radicals to approach and remove the contaminants faster. Electron paramagnetic resonance (EPR) analysis and quenching experiments revealed the coexistence of ∙OH, SO42-, and 1O2, with ∙OH dominating the system. Based on experimental and theoretical calculations, the reaction sites of CIP were predicted and the possible degradation pathways and mechanisms of Cu/Ni-MOFs@MIP/PMS systems were proposed. This study opens up a new platform for the targeted removal of target pollutants in AOPs.


Assuntos
Ciprofloxacina , Estruturas Metalorgânicas , Sulfatos , Poluentes Químicos da Água , Ciprofloxacina/química , Estruturas Metalorgânicas/química , Catálise , Poluentes Químicos da Água/química , Adsorção , Sulfatos/química , Impressão Molecular , Cobre/química , Oxirredução , Purificação da Água/métodos , Níquel/química
13.
Bioresour Technol ; 401: 130736, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670289

RESUMO

Oxygenic photogranules (OPGs) have great potential for the aeration-free treatment of various wastewater, however, the effects of wastewater carbon composition on OPGs remain unknown. This study investigated the hydrodynamic photogranulation in three types of wastewater with the same total carbon concentration but different inorganic/organic carbon compositions, each operated at two replicated reactors. Results showed that photogranulation failed in reactors fed with only inorganic carbon. In reactors with equal inorganic and organic carbon, loose-structured OPGs formed but then disintegrated. Comparatively, reactors treating organic carbon-based wastewater obtained regular and dense OPGs with better settleability, lower effluent turbidity, excellent structural stability, and higher carbon assimilation rate. Sufficient amounts of organic carbon were crucial for the formation and stability of OPGs as they promoted the secretion of extracellular polymeric substances (EPS) and the growth of filamentous cyanobacteria. This study provides a basis for the startup of OPGs process and facilitates its large-scale application.


Assuntos
Carbono , Hidrodinâmica , Compostos Orgânicos , Oxigênio , Águas Residuárias , Carbono/química , Águas Residuárias/química , Reatores Biológicos , Purificação da Água/métodos , Cianobactérias/metabolismo
14.
Molecules ; 29(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38543050

RESUMO

Stabilizing LiCoO2 (LCO) at 4.5 V rather than the common 4.2 V is important for the high specific capacity. In this study, we developed a simple and efficient way to improve the stability of LiCoO2 at high voltages. After a simple sol-gel method, we introduced trifluoroacetic acid (TA) to the surface of LCO via an afterwards calcination. Meanwhile, the TA reacted with residual lithium on the surface of LCO, further leading to the formation of uniform LiF nanoshells. The LiF nanoshells could effectively restrict the interfacial side reaction, hinder the transition metal dissolution and thus achieve a stable cathode-electrolyte interface at high working-voltages. As a result, the LCO@LiF demonstrated a much superior cycling stability with a capacity retention ratio of 83.54% after 100 cycles compared with the bare ones (43.3% for capacity retention), as well as high rate performances. Notably, LiF coating layers endow LCO with excellent high-temperature performances and outstanding full-cell performances. This work provides a simple and effective way to prepare stable LCO materials working at a high voltage.

15.
Toxics ; 12(3)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38535940

RESUMO

Persulfate-based advanced oxidation process has been proven to be a promising method for the toxic pesticide chlorpyrifos (CPY) degradation in wastewater treatment. However, due to the limitation for the short-lived intermediates detection, a comprehensive understanding for the degradation pathway remains unclear. To address this issue, density functional theory was used to analyze the degradation mechanism of CPY at the M06-2X/6-311++G(3df,3pd)//M06-2X/6-31+G(d,p) level, and computational toxicology methods were employed to explore the toxicity of CPY and its degradation products. Results show that hydroxyl radicals (·OH) and sulfate radicals (SO4•-) initiate the degradation reactions by adding to the P=S bond and abstracting the H atom on the ethyl group, rather than undergoing α-elimination of the pyridine ring in the persulfate oxidation process. Moreover, the addition products were attracted and degraded by breaking the P-O bond, while the abstraction products were degraded through dealkylation reactions. The transformation products, including 3,5,6-trichloro-2-pyridynol, O,O-diethyl phosphorothioate, chlorpyrifos oxon, and acetaldehyde, obtained through theoretical calculations have been detected in previous experimental studies. The reaction rate constants of CPY with ·OH and SO4•- were 6.32 × 108 and 9.14 × 108 M-1·s-1 at room temperature, respectively, which was consistent with the experimental values of 4.42 × 109 and 4.5 × 109 M-1 s-1. Toxicity evaluation results indicated that the acute and chronic toxicity to aquatic organisms gradually decreased during the degradation process. However, some products still possess toxic or highly toxic levels, which may pose risks to human health. These research findings contribute to understanding the transformation behavior and risk assessment of CPY in practical wastewater treatment.

16.
Int J Biol Macromol ; 266(Pt 2): 131152, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38556230

RESUMO

This study aims to seek angiotensin-I-converting enzyme inhibitory (ACEi) peptides from walnut using different enzymatic hydrolysis, and further to validate the potent ACEi peptides identified and screened via peptidomics and in silico analysis against hypertension in spontaneously hypertensive rats (SHRs). Results showed that walnut protein hydrolysate (WPH) prepared by combination of alcalase and simulated gastrointestinal digestion exhibited high ACEi activity. WPH was separated via Sephadex-G25, and four peptides were identified, screened and verified based on their PeptideRanker score, structural characteristic and ACE inhibition. Interestingly, FDWLR showed the highest ACEi activity with IC50 value of 8.02 µg/mL, which might be related to its close affinity with ACE observed in molecular docking. Subsequently, high absorption and non-toxicity of FDWLR was predicted via in silico absorption, distribution, metabolism, excretion and toxicity. Furthermore, FDWLR exhibited positively vasoregulation in Ang II-induced human umbilical vein endothelial cells, and great blood pressure lowering effect in SHRs.


Assuntos
Angiotensina II , Inibidores da Enzima Conversora de Angiotensina , Células Endoteliais da Veia Umbilical Humana , Hipertensão , Juglans , Simulação de Acoplamento Molecular , Hidrolisados de Proteína , Ratos Endogâmicos SHR , Juglans/química , Animais , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/química , Humanos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Hidrolisados de Proteína/farmacologia , Hidrolisados de Proteína/química , Ratos , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Angiotensina II/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Masculino , Peptidil Dipeptidase A/metabolismo , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/química , Pressão Sanguínea/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Proteínas de Plantas/química
18.
Water Res ; 253: 121315, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382289

RESUMO

The microalgal-bacterial granular sludge (MBGS) based enhanced biological phosphorus removal (EBPR) (MBGS-EBPR) was recently proposed as a sustainable wastewater treatment process. Previous work showed the possibility of obtaining an MBGS-EBPR process starting from mature MBGS and phosphate-accumulating organisms (PAOs) enriched aerobic granular sludge (AGS) and validated the effectiveness of removing carbon/nitrogen/phosphorus with mechanical aeration. The present work evaluated whether the same could be achieved starting from conventional activated sludge and operating under aeration-free conditions in an alternating dark/light photo-sequencing batch reactor (PSBR). We successfully cultivated filamentous MBGS with a high settling rate (34.5 m/h) and fast solid-liquid separation performance, which could be attributed to the proliferation of filamentous cyanobacteria and stimulation of extracellular polymeric substances (EPS) production. The process achieved near-complete steady-state removal of carbon (97.2 ± 1.9 %), nitrogen (93.9 ± 0.7 %), and phosphorus (97.7 ± 1.7 %). Moreover, improved phosphorus release/uptake driven by photosynthetic oxygenation under dark/light cycles suggests the enrichment of PAOs and the establishment of MBGS-EBPR. Batch tests showed similar phosphorus release rates in the dark but significantly lower phosphorus uptake rates in the presence of light when the filamentous granules were disrupted. This indicates that the filamentous structure of MBGS has minor limitations on substrate mass transfer while exerting protective effects on PAOs, thus playing an important role in sustaining the function of aeration-free EBPR. Microbial assays further indicated that the enrichment of filamentous cyanobacteria (Synechocystis, Leptoolybya, and Nodosilinea), putative PAOs and EPS producers (Hydrogenophaga, Thauera, Flavobacterium, and Bdellovibrio) promoted the development of filamentous MBGS and enabled the high-efficient pollutant removal. This work provides a feasible and cost-effective strategy for the startup and operation of this innovative process.


Assuntos
Microalgas , Esgotos , Esgotos/química , Fósforo , Reatores Biológicos/microbiologia , Fosfatos , Bactérias , Nitrogênio , Carbono
19.
Nat Commun ; 15(1): 626, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245526

RESUMO

Optoelectronic properties of semiconductors are significantly modified by impurities at trace level. Oxygen, a prevalent impurity in organic semiconductors (OSCs), has long been considered charge-carrier traps, leading to mobility degradation and stability problems. However, this understanding relies on the conventional deoxygenation methods, by which oxygen residues in OSCs are inevitable. It implies that the current understanding is questionable. Here, we develop a non-destructive deoxygenation method (i.e., de-doping) for OSCs by a soft plasma treatment, and thus reveal that trace oxygen significantly pre-empties the donor-like traps in OSCs, which is the origin of p-type characteristics exhibited by the majority of these materials. This insight is completely opposite to the previously reported carrier trapping and can clarify some previously unexplained organic electronics phenomena. Furthermore, the de-doping results in the disappearance of p-type behaviors and significant increase of n-type properties, while re-doping (under light irradiation in O2) can controllably reverse the process. Benefiting from this, the key electronic characteristics (e.g., polarity, conductivity, threshold voltage, and mobility) can be precisely modulated in a nondestructive way, expanding the explorable property space for all known OSC materials.

20.
Sci Total Environ ; 914: 169872, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199360

RESUMO

Synthetic musks (SMs) have gained widespread utilization in daily consumer products, leading to their widespread dissemination in aquatic environments through various pathways. Over the past few decades, the production of SMs has consistently risen, prompting significant concern over their potential adverse impacts on ecosystems and human health. Although several studies have focused on the development of analytical techniques for detecting SMs in biological samples and cosmetic products, a comprehensive evaluation of their global distribution in diverse aquatic media and biological matrices remains lacking. This review aims to provide an up-to-date overview of the occurrence of SMs in both aquatic and various biological matrices, investigating their worldwide distribution trends, assessing their ecological toxicity, and comparing different methodologies for processing and analysis of SMs. The findings underscore the prevalence of polycyclic musks as predominant SMs, with consumption of various products in different countries leading to contrasting distribution of contaminants. Furthermore, the migration of SMs from sediments to the water phase is investigated, indicating the role of solid-phase reservoirs. Incomplete degradation of SMs in the environment could contribute to their accumulation in aquatic systems, impacting the growth and oxidative stress of aquatic organisms, and having a possibility of genotoxicity to them. Human exposure data highlight substantial risks for vulnerable populations such as pregnant women and infants. Moreover, contemporary methods for SMs analysis are presented in this review, particularly focusing on advancements made in the last five years. Finally, research enhancement and critical questions regarding the analysis of SMs are provided, offering suggestions for future research endeavors.


Assuntos
Cosméticos , Poluentes Químicos da Água , Gravidez , Humanos , Feminino , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Organismos Aquáticos
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