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1.
Small ; : e2402074, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38794990

ABSTRACT

The high theoretical energy density (2600 Wh kg-1) and low cost of lithium-sulfur batteries (LSBs) make them an ideal alternative for the next-generation energy storage system. Nevertheless, severe capacity degradation and low sulfur utilization resulting from shuttle effect hinder their commercialization. Herein, Single-atom Ru-doped 1T/2H MoS2 with enriched defects decorates V2C MXene (Ru-MoS2/MXene) produced by a new phase-engineering strategy employed as sulfur host to promote polysulfide adsorption and conversion reaction kinetics. The Ru single atom-doped adjusts the chemical environment of the MoS2/MXene to anchor polysulfide and acts as an efficient center to motivate the redox reaction. In addition, the rich defects of the MoS2 and ternary boundary among 1T/2H MoS2 and V2C accelerate the charge transfer and ion movements for the reaction. As expected, the Ru-MoS2/MXene/S cathode-based cell exhibits a high-rate capability of 684.3 mAh g-1 at 6 C. After 1000 cycles, the Ru-MoS2/MXene/S cell maintains an excellent cycling stability of 696 mAh g-1 at 2 C with a capacity degradation as low as 0.02% per cycle. Despite a high sulfur loading of 9.5 mg cm-2 and a lean electrolyte-to-sulfur ratio of 4.3, the cell achieves a high discharge capacity of 726 mAh g-1.

2.
Sci Total Environ ; 927: 172268, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38583629

ABSTRACT

Due to the inappropriate disposal of waste materials containing lead (Pb) and irrigation with sewage containing Pb, the migration of Pb2+ within the soil profile has been extensively investigated. The conventional Pb2+ block method is challenging to implement due to its complex operational procedures and high construction costs. To address this issue, this study introduces the microbial-induced carbonate precipitation (MICP) technique as a novel approach to impede the migration of Pb2+ in the soil profile. Soil acclimatization with urea resulted in an increased proportion of urease-producing microorganisms, including Bacillus, Paenibacillus, and Planococcaceae, along with heightened expression of urea-hydrolyzing genes (UreA, UreB, UreC, and UreG). This indicates that urea-acclimatized soil (Soil-MICP) possesses the potential to induce carbonate precipitation. Batch Pb2+ fixation experiments confirmed that the fixation efficiency of Soil-MICP on Pb2+ exceeded that of soil without MICP, attributed to the MICP process within the Soil-MICP group. Dynamic migration experiments revealed that the MICP reaction transformed exchangeable lead into carbonate-bound Pb, effectively impeding Pb2+ migration in the soil profile. Additionally, the migration rate of Pb2+ in Soil-MICP was influenced by varying urea amounts, pH levels, and pore flow rates, leading to a slowdown in migration. The Two-site sorption model aptly described the Pb2+ migration process in the Soil-MICP column. This study aims to elucidate the MICP biomineralization process, uncover the in-situ blocking mechanism of MICP on lead in soil, investigate the impact of Pb on key genes involved in urease metabolism, enhance the comprehension of the chemical morphology of lead mineralization products, and provide a theoretical foundation for MICP technology in preventing the migration of Pb2+ in soil profiles.


Subject(s)
Carbonates , Lead , Soil Microbiology , Soil Pollutants , Soil , Soil/chemistry , Urease/metabolism , Chemical Precipitation
3.
Expert Rev Vaccines ; 22(1): 193-206, 2023.
Article in English | MEDLINE | ID: mdl-36719062

ABSTRACT

INTRODUCTION: Studies on economic evaluations of the 13-valent pneumococcal conjugate vaccine (PCV13) have been increasing over the last decade. No systematic reviews have synthesized the evidence of economic evaluations of the PCV13. AREAS COVERED: We systematically searched the literature which published on peer-reviewed journals from January 2010 to June 2022. The literature search was conducted in the following electronic databases: PubMed, Web of Science, Embase, the Cochrane Library, CNKI, Wanfang database, VIP database. We identified 1827 records from the database search. After excluding 511 duplicates, 1314 records were screened, of which 156 records were retained for the full-text reviews. A total of 44 studies were included in the review. Among the included studies, 33 studies were economic evaluations of PCV13 among children, and 11 studies were conducted among adults. The literature search initiated in April, 2022, and updated in June 2022. EXPERT OPINION: Vaccination with PCV13 was found to significantly reduce the mortality and morbidity of pneumococcal diseases and was cost-effective compared to no vaccine or several other pneumococcal vaccines (e.g. PCV10, PPV23). Future research is advised to expand economic evaluations of PCV13 combined with dynamic model to enhance methodologic rigor and prediction accuracy.


Subject(s)
Pneumococcal Infections , Pneumococcal Vaccines , Adult , Child , Humans , Cost-Benefit Analysis , Vaccines, Conjugate , Pneumococcal Infections/prevention & control , Vaccination
4.
Chemosphere ; 318: 137894, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36657570

ABSTRACT

The occurrence of imbalanced heavy metals concentration due to anthropogenic hindrances in the aquatic and terrestrial environment has become a potential risk to life after circulating through different food chains. The microbial-induced carbonate precipitation (MICP) method has gradually received great attention from global researchers but the underlying mechanism of heavy metal mineralization is not well-understood and challenging, limiting the applications in wastewater engineering. This paper reviews the metabolic pathways, mechanisms, operational factors, and mathematical/modeling approaches in the MICP process. Subsequently, the recent advancement in MICP for the remediation of heavy metal pollution is being discussed. In the follow-up, the key challenges and prospective associated with technical bottlenecks of MICP method are elaborated. The prospective study reveals that MICP technology could be efficiently used to remediate heavy metal contaminants from the natural environment in a cost-effective way and has the potential to improve soil properties while remediating heavy metal contaminated soil.


Subject(s)
Metals, Heavy , Soil Pollutants , Prospective Studies , Metals, Heavy/metabolism , Carbonates , Biodegradation, Environmental , Soil , Soil Pollutants/metabolism , Calcium Carbonate/metabolism
5.
Chemosphere ; 311(Pt 2): 137173, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36356804

ABSTRACT

The environmental conditions at a contaminated site will impact on the indigenous microbial communities, with implications for the removal of pollutants. An analysis of the characteristics of microbial communities in petroleum-contaminated groundwater can give insights into the relationships between microbial community and environmental factors, and provide guidance about how microbes can be used to remediate and regulate petroleum-contaminated groundwater. This study focuses on two petroleum-contaminated sites in northeast China, the physico-chemical-biological changes in petroleum-contaminated groundwater were analyzed, the response relationship between hydro-chemical indicators and microbial communities was characterized, and the bioindicator that can reflect the petroleum contamination status were established for environmental monitoring and management. The results showed that Proteobacteria was the dominant bacteria in petroleum-contaminated groundwater, with a relative abundance of 42.45%-91.19%. pH, TDS, DO, NO3-, NO2-, SO42-, NH4+, Al, and Mn have significant effects on microbial community. The effect of petroleum pollutants on microbial communities is not only related to the concentration and composition of the pollutants themselves, but also could indirectly affect microbial communities by changing the content of inorganic electron acceptor components such as iron, manganese, sulfate and nitrate in groundwater, and this indirect effect is significantly greater than the direct impact of pollutants on microbial communities. In petroleum-contaminated groundwater, the dominant genera (Polaromonas, Caulobacter) and microbial metabolic functions (methanol oxidation, methylotrophy, ureolysis, and reductive biosynthesis) of the indigenous microbial community can be used as bioindicators to indicate petroleum contamination status. The higher abundance of these bioindicators in petroleum-contaminated groundwater, the more serious petroleum pollution in groundwater.

6.
Ecotoxicol Environ Saf ; 246: 114139, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36193588

ABSTRACT

The resistance mechanism of microbial communities in contaminated groundwater under combined stresses of aromatic hydrocarbons (AHs), NH4+, and Fe-Mn exceeding standard levels was studied in an abandoned oil depot in Northeast China. The response of environmental parameters and microbial communities under different pollution levels in the study area was discussed, and microscopic experiments were conducted using background groundwater with different AHs concentrations. The results showed that indigenous microbial community were significantly affected by environmental factors, including pH, TH, CODMn, TFe, Cr (VI), NH4+, NO3-, and SO42-. AHs likely had a limited influence on microbial communities, mainly causing indirect changes in the microbial community structure by altering the electron donor/acceptor (mainly Fe, Mn, NO3-, NO2-, NH4+, and SO42-) content in groundwater, and there was no linear effect of AHs content on the microbial community. In low- and medium-AHs-contaminated groundwater, the microbial diversity increased, whereas high AHs contents decreased the diversity of the microbial community. The microbial community had the strongest ability to metabolize AHs in the medium-AHs-contaminated groundwater. In the high-AHs-contaminated groundwater, microbial communities mainly degraded AHs through a complex co-metabolic mechanism due to the inhibitory effect caused by the high concentration of AHs, whereas in low-AHs-contaminated groundwater, microbial communities mainly caused a mutual transformation of inorganic electron donors/acceptors (mainly including N, S), and the microbial community's ability to metabolize AHs was weak. In the high-AHs-contaminated groundwater, the microbial community resisted the inhibitory effect of AHs mainly via a series of resistance mechanisms, such as regulating their life processes, avoiding unfavorable environments, and enhancing their feedback to the external environment under high-AHs-contaminated conditions.


Subject(s)
Groundwater , Hydrocarbons, Aromatic , Microbiota , Water Pollutants, Chemical , Biodegradation, Environmental , Water Pollutants, Chemical/analysis , Groundwater/chemistry
7.
Sci Total Environ ; 844: 157167, 2022 Oct 20.
Article in English | MEDLINE | ID: mdl-35792264

ABSTRACT

Cadmium (Cd)-containing wastewater has been used to irrigate agricultural land. However, long term usage has resulted in the accumulation of Cd in the soil systems, which can eventually leach into the aquifer, contaminating groundwater. Microbial-induced carbonate precipitation (MICP), an economical and effective method, was used to block the in situ migration of Cd2+ in the soil profile. The results of the laboratory experiments showed that the maximum Cd2+ adsorption capacity of the soil exposed to MICP (8.92 mg/g) was higher than that of soil without MICP (7.12 mg/g). The Thomas model provided a good fit for the Cd2+ migration process in soil exposed to MICP (R2 > 0.96), and Cd2+ was trapped more effectively by soil exposed to MICP than by soil alone. Further testing showed that the Cd2+ retention time in the MICP soil column increased with increasing soil urea content and pH but decreased with increasing flow rate. Soil physico-chemical properties showed that the MICP process increased the soil particle size and Cd capacity and decreased the proportion of exchangeable Cd in the soil. Scanning electron microscopy and X-ray diffraction analyses confirmed the generation of CdCO3 in the MICP soil column. The findings of this study indicate that MICP can be effectively used to immobilize Cd2+ and prevent its migration in the soil profile.


Subject(s)
Cadmium , Soil , Cadmium/chemistry , Calcium Carbonate/chemistry , Carbonates/chemistry , Chemical Precipitation , Soil/chemistry , Soil Microbiology
8.
Sci Rep ; 12(1): 6495, 2022 04 20.
Article in English | MEDLINE | ID: mdl-35444191

ABSTRACT

This study aims to improve soil vapor extraction (SVE) to address its shortcomings in treating halogenated hydrocarbon-contaminated soil. Indoor simulation experiments based on SVE were conducted to provide technical guidance for the remediation of 1,2-DCA-contaminated soil, with the overall intention of soil repair and ecological restoration. A thermal oxidation SVE (TOSVE) system was designed on the basis of SVE technology for application in the remediation of low-permeability soil contaminated with halogenated hydrocarbons from a chemical plant in Northeast China. Laboratory simulation experiments were conducted based on TOSVE technology to study the removal of target pollutants under different organic contents, moisture and air speeds. For the first time, a new material, scoria, was added to the oxidant at different proportions, and its effect on the exhaust gas treatment efficiency was examined. Thermal extraction improved the extraction efficiency of pollutants from low-permeability soil. Moreover, the adsorption-oxidation effect of 0.1-0.25 mm scoria prepared by 20% Na2S2O8 on 1,2-dichloroethane (1,2-DCA) in tail gas was higher than that of the oxidant without scoria, indicating that scoria is effective in tail gas treatment.


Subject(s)
Environmental Pollutants , Environmental Restoration and Remediation , Soil Pollutants , Gases , Oxidants , Soil/chemistry , Soil Pollutants/analysis
9.
Sci Total Environ ; 817: 153036, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35026256

ABSTRACT

The resistance mechanism of microbial communities in contaminated groundwater under the combined stress of sulfonamide antibiotics (SAs), NH4+, and Fe-Mn exceeding the standard levels was studied in an agricultural area along the Songhua River in Northeast China with developed livestock and poultry breeding. Representative points were selected in the study area to explore the response of environmental parameters and microbial communities, and microscopic experiments with different SA concentrations were conducted with background groundwater. The results showed a complex relationship between microbial communities and environmental factors. The environmental factors SM, SM2, SMX, DOC, NO3-, Fe, Mn, and HCO3- significantly affected the microbial community, with SMX, DOC, and Mn having the greatest effect. Three types of antibiotics with similar properties had different effects on the microbial community, and these effects were not simply additive or superimposed. After adding SAs, Proteobacteria with multi-resistance (99.85%) became the dominant phylum, and Acinetobacter (98.68%) became the dominant genus with SA resistance. SAs have a significant influence on bacterial chemotaxis, transporters, substance transport, and metabolism. Microorganisms resist the influence of SAs via a series of resistance mechanisms, such as enhancing the synthesis of relevant enzymes, generating new biochemical reactions, and reducing the transport of harmful substances through cell membranes. We also found that the proportion of exogenous compound degradation and metabolism-related functional genes in the presence of high SA concentrations increased significantly, which may be related to the degradation of SAs by microorganisms.


Subject(s)
Groundwater , Microbiota , Anti-Bacterial Agents , Groundwater/chemistry , Rivers , Sulfonamides
10.
Chemosphere ; 287(Pt 2): 132156, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34826898

ABSTRACT

In the recent decades, due to rapid increase in industrialization, urbanization, anthropogenic activity in the catchments, removal of heavy metals contaminants in wastewater has become global challenges. Numerous advance technologies have been introduced to deal with these problems but failed in reducing adequate pollution load in the contaminated water and/or wastewater. In this study, sulfur-ferromagnetic nanoparticles (SFMNs) were synthesized by modification of nano-Fe3O4, which can be rapidly separated from the environment by an external magnetic field after in situ repair. Its structure and physical properties were characterized by conventional techniques included Transmission electron microscope (TEM), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The ability of the SFMNs to remove Pb2+ and Cd2+ was studied at different temperatures and initial metal ions concentrations. The adsorption kinetics showed that the adsorption equilibrium time of Pb2+ and Cd2+ was 300 min consequently adsorption process of SFMNs fit well (R2 > 0.99) with pseudo-second-order model. The adsorption thermodynamics showed that the adsorption of Pb2+ and Cd2+ on SFMNs is spontaneous (negative value of ΔG0) endothermic process (positive value of ΔH0) and fit well (R2 > 0.98) with the Langmuir isothermal model. Density functional theory (DFT) calculations show that SFMNs can transfer electrons to Pb2+ and Cd2+, and the metal ions form stable chelates on the ligand surface. This study implies that newly synthesized sulfur-ferromagnetic nanoparticles could play an instrumental role in metal ions removal from water and wastewater.


Subject(s)
Nanoparticles , Water Pollutants, Chemical , Cadmium , Lead , Sulfur , Wastewater , Water Pollutants, Chemical/analysis
11.
Nanoscale ; 12(7): 4729-4735, 2020 Feb 20.
Article in English | MEDLINE | ID: mdl-32049081

ABSTRACT

Organic electrode materials have secured a distinctive place among the auspicious choices for modern energy storage systems due to their resource sustainability and environmental friendliness. Herein, a novel all-organic electrode-based sodium ion full battery is demonstrated using 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA) as raw material for the assembly of positive and negative electrodes. Both the electrodes exhibit excellent cycling stability and rate performance. The fabricated organic sodium ion full battery not only displays a high initial capacity of 157 mA h g-1 with an average battery voltage of 1.47 V under the current density of 100 mA g-1, but also delivers a high energy density of 254 W h kg-1 and a high power density of 614 W kg-1. These sodium ion batteries with organic positive and negative electrode materials can provide a new way for energy storage devices.

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