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1.
Chemosphere ; 362: 142682, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38914286

ABSTRACT

The escalating threat of Cr(VI) pollution to the environment and human health can be effectively controlled through microbial methods, which are promising, safe, and ecofriendly. To enhance Cr(VI) removal efficiency, scholars have been optimizing strains. However, synergies between in-situ soil particles and crucial microorganisms in soil have rarely been investigated. In this study, Cr(VI) was removed by collaborating with in-situ soil particles and key microorganisms in the soil. The results indicated that within 48 hours, the removal rate of Cr(VI) reached over 99% in the soils+microflora system, which was 45% higher than that of the microflora system alone. Factors such as Cr(VI) concentration, soil dosage, pH level, oxygen availability, and electron donors influenced the removal efficiency of Cr(VI) in the soils+microflora system. The cyclic experiments showed that soil particles effectively prevented chromium invasion on microflora, promoting the growth of crucial microorganisms. The addition of microflora can effectively regulate the composition of soil flora and enhance the efficiency of chromium reduction. Moreover, two strains each of Ochrobactrum sp. and Paenarthrobacter sp., exhibiting remarkable tolerance to Cr(VI), were successfully isolated from these soils, significantly enhancing the reduction capacity of the indigenous microflora towards Cr(VI). Additionally, 16S rRNA-PCR sequence analysis revealed that in-situ soil particles not only synergistically collaborated with the resident microflora for efficient removal of Cr(VI), but also facilitated the proliferation of key microbiota such as Ochrobactrum sp. and Paenarthrobacter sp. Remarkably, when exposed to an initial concentration of 50 mg/L Cr(VI), complete removal was achieved by Paenarthrobacter-2 within a time frame as short as 60 hours. This research found four novel highly efficient strains for reducing Cr(VI) and provides an innovative method for the synergistic interaction between indigenous soil microflora and soil particles to remove heavy metal ions from wastewater.

2.
Virol J ; 21(1): 146, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38918816

ABSTRACT

The genus Jeilongvirus comprises non-segmented negative-stranded RNA viruses that are classified within the Paramyxoviridae family by phylogeny. Jeilongviruses are found in various reservoirs, including rodents and bats. Rodents are typical viral reservoirs with diverse spectra and zoonotic potential. Little is currently known about jeilongviruses in rodents from central China. The study utilized high-throughput and Sanger sequencing to obtain jeilongvirus genomes, including those of two novel strains (HBJZ120/CHN/2021 (17,468 nt) and HBJZ157/CHN/2021 (19,143 nt)) and three known viruses (HBXN18/CHN/2021 (19,212 nt), HBJZ10/CHN/2021 (19,700 nt), HBJM106/CHN/2021 (18,871 nt)), which were characterized by genome structure, identity matrix, and phylogenetic analysis. Jeilongviruses were classified into three subclades based on their topology, phylogeny, and hosts. Based on the amino acid sequence identities and phylogenetic analysis of the L protein, HBJZ120/CHN/2021 and HBJZ157/CHN/2021 were found to be strains rather than novel species. Additionally, according to specific polymerase chain reaction screening, the positive percentage of Beilong virus in Hubei was 6.38%, suggesting that Beilong virus, belonging to the Jeilongvirus genus, is likely to be widespread in wild rodents. The identification of novel strains further elucidated the genomic diversity of jeilongviruses. Additionally, the prevalence of jeilongviruses in Hubei, China, was profiled, establishing a foundation for the surveillance and early warning of emerging paramyxoviruses.


Subject(s)
Genome, Viral , Phylogeny , Rodentia , Animals , China , Rodentia/virology , Animals, Wild/virology , Paramyxovirinae/genetics , Paramyxovirinae/classification , Paramyxovirinae/isolation & purification , RNA, Viral/genetics , Paramyxoviridae Infections/veterinary , Paramyxoviridae Infections/virology , Paramyxoviridae Infections/epidemiology , High-Throughput Nucleotide Sequencing , Disease Reservoirs/virology , Sequence Analysis, DNA
3.
J Hazard Mater ; 472: 134515, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38703676

ABSTRACT

The efficient activation and selective high-valent metal-oxo (HVMO) species generation remain challenging for peroxymonosulfate (PMS)-based advanced oxidation processes (PMS-AOPs) in water purification. The underlying mechanism of the activation pathway is ambiguous, leading to a massive dilemma in the control and regulation of HVMO species generation. Herein, bioinspired by the bio-oxidase structure of cytochrome P450, the axial coordination strategy was adopted to tailor a single-atom cobalt catalyst (CoN4S-CB) with an axial S coordination. CoN4S-CB high-selectively generated high-valent Co-Oxo species (Co(IV)=O) via PMS activation. Co(IV)=O demonstrated an ingenious oxygen atom transfer (OAT) reaction to achieve the efficient degradation of sulfamethoxazole (SMX), and this allowed robust operation in various complex environments. The axial S coordination modulated the 3d orbital electron distribution of the Co atom. Density functional theory (DFT) calculation revealed that the axial S coordination decreased the energy barrier for PMS desorption and lowered the free energy change (ΔG) for Co(IV)=O generation. CoN4S-PMS* had a narrow d-band close to the Fermi level, which enhanced charge transfer to accelerate the cleavage of O-O and O-H bonds in PMS. This work provides a broader perspective on the activator design with natural enzyme structure-like active sites to efficient activate PMS for selective HVMO species generation.


Subject(s)
Cobalt , Oxidation-Reduction , Peroxides , Cobalt/chemistry , Catalysis , Peroxides/chemistry , Sulfamethoxazole/chemistry , Water Purification/methods , Water Pollutants, Chemical/chemistry , Oxygen/chemistry , Cytochrome P-450 Enzyme System/chemistry , Cytochrome P-450 Enzyme System/metabolism , Density Functional Theory
4.
Infect Genet Evol ; 121: 105602, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38734397

ABSTRACT

Hepatitis E, caused by the hepatitis E virus (HEV), is a global public health issue. Low similarity between the gene sequences of mouse and human HEV led to the belief that the risk of human infection was low. Recent reports of chronic and acute hepatitis E caused by murine HEV infection in humans in Hong Kong have raised global concerns. Therefore, it is crucial to investigate the epidemiology and prevalence of HEV in China. We comprehensively analyzed different rodent HEV strains to understand rocahepevirus occurrence in Hubei Province, China. The HEV positivity rate for was 6.43% (73/1136). We identified seven near-full-length rocahepevirus strains and detected rat HEV antigens in tissues from different mouse species. HEV has extensive tissue tropism and a high viral load in the liver. We highlight the genetic diversity of HEVs in rodents and underscore the importance of paying attention to their variation and evolution.


Subject(s)
Hepatitis E virus , Hepatitis E , Phylogeny , Hepatitis E virus/genetics , Hepatitis E virus/classification , Animals , China/epidemiology , Hepatitis E/epidemiology , Hepatitis E/veterinary , Hepatitis E/virology , Prevalence , Mice , Rodentia/virology , Rats , Animals, Wild/virology , Genetic Variation
5.
Gen Hosp Psychiatry ; 88: 61-67, 2024.
Article in English | MEDLINE | ID: mdl-38508077

ABSTRACT

CONTEXT: Many patients recovering from surgery in wards are disturbed by environmental noise. However, the effects of environmental noise on postoperative pain are unclear. OBJECTIVES: This study aimed to assess the association between postoperative noise and pain. METHODS: This prospective study included 182 women who underwent cesarean sections. Postoperative noise was continuously recorded, and pain intensity at rest was assessed using a numerical rating scale (NRS) for 0-6, 6-12, 12-18, and 18-24 h after the patients were returned to the ward. Cumulative pain scores were calculated by summing the NRS scores at each time point and comprised the primary outcome. The maximum pain NRS score and analgesic consumption during the 24 h after surgery were also recorded. RESULTS: Mean environmental noise intensity during the daytime was an independent factor for cumulative pain scores, maximum pain scores, and analgesic use during the first postoperative 24 h (ß, 0.37; 95% CI, 0.21-0.53 and ß, 0.12; 95% CI, 0.07-0.17; P < 0.001 for both; ß, 0.86; 95% CI, 0.25-1.46; P = 0.006). Cumulative and maximum NRS pain scores as well as the incidence of NRS ≥ 4 were significantly higher in patients under mean daytime environmental noise of ≥58, than <58 decibels (dB) (8.0 [6.0-11.3] vs. 6.0 (5.0-7.0); 3.0 [2.0-4.0] vs. 2.0 [2.0-2.0, and 25.6% vs. 11.0%; RR, 2.32; 95% CI, 1.19-4.54, respectively; P < 0.001 for all). CONCLUSIONS: Higher-level postoperative noise exposure was associated with more severe postoperative pain and increased analgesic needs, as well as a higher incidence of moderate-to-severe pain in patients recovering from cesarean delivery. Our findings indicate that reducing environmental ward noise might benefit for postoperative pain management.


Subject(s)
Analgesics , Pain, Postoperative , Pregnancy , Humans , Female , Prospective Studies , Analgesics/therapeutic use , Pain, Postoperative/epidemiology , Pain, Postoperative/etiology , Pain Measurement , Analgesics, Opioid
6.
Article in English | MEDLINE | ID: mdl-38194387

ABSTRACT

Partial label learning (PLL) studies the problem of learning instance classification with a set of candidate labels and only one is correct. While recent works have demonstrated that the Vision Transformer (ViT) has achieved good results when training from clean data, its applications to PLL remain limited and challenging. To address this issue, we rethink the relationship between instances and object queries to propose K-means cross-attention transformer for PLL (KMT-PLL), which can continuously learn cluster centers and be used for downstream disambiguation tasks. More specifically, K-means cross-attention as a clustering process can effectively learn the cluster centers to represent label classes. The purpose of this operation is to make the similarity between instances and labels measurable, which can effectively detect noise labels. Furthermore, we propose a new corrected cross entropy formulation, which can assign weights to candidate labels according to the instance-to-label relevance to guide the training of the instance classifier. As the training goes on, the ground-truth label is progressively identified, and the refined labels and cluster centers in turn help to improve the classifier. Simulation results demonstrate the advantage of the KMT-PLL and its suitability for PLL.

7.
IEEE Trans Image Process ; 33: 610-624, 2024.
Article in English | MEDLINE | ID: mdl-38190673

ABSTRACT

Recent developments in the field of non-local attention (NLA) have led to a renewed interest in self-similarity-based single image super-resolution (SISR). Researchers usually use the NLA to explore non-local self-similarity (NSS) in SISR and achieve satisfactory reconstruction results. However, a surprising phenomenon that the reconstruction performance of the standard NLA is similar to that of the NLA with randomly selected regions prompted us to revisit NLA. In this paper, we first analyzed the attention map of the standard NLA from different perspectives and discovered that the resulting probability distribution always has full support for every local feature, which implies a statistical waste of assigning values to irrelevant non-local features, especially for SISR which needs to model long-range dependence with a large number of redundant non-local features. Based on these findings, we introduced a concise yet effective soft thresholding operation to obtain high-similarity-pass attention (HSPA), which is beneficial for generating a more compact and interpretable distribution. Furthermore, we derived some key properties of the soft thresholding operation that enable training our HSPA in an end-to-end manner. The HSPA can be integrated into existing deep SISR models as an efficient general building block. In addition, to demonstrate the effectiveness of the HSPA, we constructed a deep high-similarity-pass attention network (HSPAN) by integrating a few HSPAs in a simple backbone. Extensive experimental results demonstrate that HSPAN outperforms state-of-the-art approaches on both quantitative and qualitative evaluations. Our code and a pre-trained model were uploaded to GitHub (https://github.com/laoyangui/HSPAN) for validation.

8.
Water Res ; 245: 120589, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37708773

ABSTRACT

Elemental sulfur (S0) plays a vital role in the coupled cycling of sulfur and iron, which in turn affects the transformation of carbon and various pollutants. These processes have been well characterized under static anoxic or oxic conditions, however, how the natural redox fluctuations affect the bio-mediated sulfur cycling and coupled iron cycling remain enigmatic. The present work examined S0 disproportionation as driven by natural microbial communities under fluctuating redox conditions and the contribution of S0 disproportionation to ferrihydrite transformation. Samples were incubated at either neutral or alkaline pH values, applying sequential anaerobic, aerobic and anaerobic conditions over 60 days. Under anaerobic conditions, S0 was found to undergo disproportionation to sulfate and sulfide, which subsequently reduced ferrihydrite at both pH 7.4 and 9.5. Ferrihydrite promoted S0 disproportionation by scavenging biogenic sulfide and maintaining a suitable degree of sulfate formation. After an oxic period, during the subsequent anoxic incubation, bioreduction of sulfate occurred and the biogenic sulfide reduced iron (hydr)oxides at a rate approximately 25 % lower than that observed during the former anoxic period. A 16S rDNA-based microbial community analysis revealed changes in the microbial community in response to the redox fluctuations, implying an intimate association with the coupled cycling of sulfur and iron. Microscopic and spectroscopic analyses confirmed the S0-mediated transformation of ferrihydrite to crystalline iron (hydr)oxide minerals such as lepidocrocite and magnetite and the formation of iron sulfides precipitated under fluctuating redox conditions. Finally, a reaction mechanism based on mass balance was proposed, demonstrating that bio-mediated sulfur transformation maintained a sustainable redox reaction with iron (hydr)oxides under fluctuating anaerobic-aerobic-anaerobic conditions tested in this study. Altogether, the finding of our study is critical for obtaining a more complete understanding of the dynamics of iron redox reactions and pollutant transformation in sulfur-rich aquatic environments.

9.
J Phys Chem Lett ; 14(38): 8563-8570, 2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37724994

ABSTRACT

Nanomaterials of halide perovskites have attracted increasing attention for their remarkable potential in optoelectronic devices, but their instability to environmental factors is the core issue impeding their applications. In this context, the microscopic understanding of their structural degradation mechanisms upon external stimuli remains incomplete. Herein, we took an emerging member of this material family, Cs4PbBr6 nanocrystals (NCs), as an example and investigated the degradation pathways as well as underlying mechanisms under an electron beam by using in situ transmission electron microscopy. Our atomic-scale study identified the distinct degradation stages for the NCs toward interesting coffee-ring PbBr2 structures, which are caused by the organic surface capping agents as well as surface energy of NCs. Our findings present a fundamental insight for the degradation of halide perovskite NCs and may provide indispensable guidance for their structural design and stability improvement.

10.
Environ Sci Pollut Res Int ; 30(39): 91125-91139, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37470976

ABSTRACT

Dewatering is critical to oily cold rolling mill (CRM) sludge treatment. Therefore, finding an efficient, energy-saving, and applicable dewatering technology for oily CRM sludge is still urgent. This study investigated the performance of quicklime as a conditioning agent for oily CRM sludge conditioning and dewatering. The interactive effects of quicklime dosage, temperature, and time on filter cake's specific resistance to filtration (SRF) and the dewatering rate of oily CRM sludge were studied by response surface methodology (RSM). The optimal parameters for conditioning oily CRM sludge were quicklime dosage of 18.7%, temperature of 54 °C, and time of 43.3 min, which resulted in filter cake SRF of 0.50 × 1010 m/kg and dewatering rate of 61.2%. The viscosity of oily CRM sludge could be reduced by 90% after conditioned with quicklime, which caused by the neutralization or hydrolysis of high viscosity organic matter in the oil phase with quicklime to produce low viscosity organic matter. The study indicated the excellent performance of quicklime as a conditioning agent for oily CRM sludge treatment and provided an effective route for the recycling of the oily CRM sludge for steel production.


Subject(s)
Oxides , Sewage , Calcium Compounds , Cold Temperature , Filtration , Oils , Water , Waste Disposal, Fluid/methods
11.
Environ Sci Pollut Res Int ; 30(40): 91617-91635, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37516705

ABSTRACT

The semi-dry flue gas desulfurization ash (SFGDA) is an industrial waste generated by the semi-dry desulfurization process, and its resources have been continuously attracted attention. Through the method of heat decomposition, the SFGDA decomposed into CaO and SO2 has emerged as a prominent research topic. This paper summarizes various of research workers, who revealed that the decomposition temperature of CaSO4 in SFGDA is greater than 1678 K and 1603 K in the air atmosphere and N2 atmosphere, respectively, presenting challenges such as high energy consumption and limited economic feasibility. On the one hand, the effects of CO and C regulating the pyrolysis atmosphere on reducing the pyrolysis temperature were reviewed. On the other hand, the impact of additives such as Fe2O3 and FeS2 was considered. Ultimately, the joint effects of regulating atmosphere and additives were discussed, and an efficient and low-temperature decomposition route was obtained; adding solid C source and Fe2O3 for pyrolysis reaction, the decomposition temperature of CaSO4 can be reduced by at least 230 K and desulfurization efficiency exceeds 95% under the condition of micro-oxidizing atmosphere. Moreover, the CaO resulting from SFGDA decomposition can be further synthesized into calcium ferrite, while the enriched SO2 can be utilized for the production of industrial sulfuric acid, which holds promising prospects for large-scale industrial applications.


Subject(s)
Gases , Hot Temperature , Humans , Temperature , Cold Temperature , Industrial Waste
12.
Behav Brain Res ; 452: 114569, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37419331

ABSTRACT

This study aimed to explore the role of SYNJ1 in Parkinson's disease (PD) and its potential as a neuroprotective factor. We found that SYNJ1 was decreased in the SN and striatum of hSNCA*A53T-Tg and MPTP-induced mice compared to normal mice, associated with motor dysfunction, increased α-synuclein and decreased tyrosine hydroxylase. To investigate its neuroprotective effects, SYNJ1 expression was upregulated in the striatum of mice through injection of the rAdV-Synj1 virus into the striatum, which resulted in the rescue of behavioral deficiencies and amelioration of pathological changes. Subsequently, transcriptomic sequencing, bioinformatics analysis and qPCR were conducted in SH-SY5Y cells following SYNJ1 gene knockdown to identify its downstream pathways, which revealed decreased expression of TSP-1 involving extracellular matrix pathways. The virtual protein-protein docking further suggested a potential interaction between the SYNJ1 and TSP-1 proteins. This was followed by the identification of a SYNJ1-dependent TSP-1 expression model in two PD models. The coimmunoprecipitation experiment verified that the interaction between SYNJ1 and TSP-1 was attenuated in 11-month-old hSNCA*A53T-Tg mice compared to normal controls. Our findings suggest that overexpression of SYNJ1 may protect hSNCA*A53T-Tg and MPTP-induced mice by upregulating TSP-1 expression, which is involved in the extracellular matrix pathways. This suggests that SYNJ1 could be a potential therapeutic target for PD, though more research is needed to understand its mechanism.


Subject(s)
Neuroblastoma , Neuroprotective Agents , Parkinson Disease , Mice , Humans , Animals , Parkinson Disease/genetics , Parkinson Disease/drug therapy , Thrombospondin 1 , Neuroblastoma/drug therapy , alpha-Synuclein/genetics , alpha-Synuclein/metabolism , Neuroprotective Agents/pharmacology , Neuroprotection , Mice, Inbred C57BL , Disease Models, Animal
13.
Microorganisms ; 11(5)2023 Apr 30.
Article in English | MEDLINE | ID: mdl-37317159

ABSTRACT

Soil, sediment, and waters contaminated with heavy metals pose a serious threat to ecosystem function and human health, and microorganisms are an effective way to address this problem. In this work, sediments containing heavy metals (Cu, Pb, Zn, Mn, Cd, As) were treated differently (sterilized and unsterilized) and bio-enhanced leaching experiments were carried out with the addition of exogenous iron-oxidizing bacteria A. ferrooxidans and sulfur-oxidizing bacteria A. thiooxidans. The leaching of As, Cd, Cu, and Zn was higher in the unsterilized sediment at the beginning 10 days, while heavy metals leached more optimally in the later sterilized sediment. The leaching of Cd from sterilized sediments was favored by A. ferrooxidans compared to A. thiooxidans. Meanwhile, the microbial community structure was analyzed using 16S rRNA gene sequencing, which revealed that 53.4% of the bacteria were Proteobacteria, 26.22% were Bacteroidetes, 5.04% were Firmicutes, 4.67% were Chlamydomonas, and 4.08% were Acidobacteria. DCA analysis indicated that microorganisms abundance (diversity and Chao values) increased with time. Furthermore, network analysis showed that complex networks of interactions existed in the sediments. After adapting to the acidic environmental conditions, the growth of some locally dominant bacteria increased the microbial interactions, allowing more bacteria to participate in the network, making their connections stronger. This evidence points to a disruption in the microbial community structure and its diversity following artificial disturbance, which then develops again over time. These results could contribute to the understanding of the evolution of microbial communities in the ecosystem during the remediation of anthropogenically disturbed heavy metals.

14.
Materials (Basel) ; 16(9)2023 May 05.
Article in English | MEDLINE | ID: mdl-37176423

ABSTRACT

Phosphogypsum and red mud are bulk industrial solid wastes that trigger local environmental problems. In the present investigation, an efficient valorization process was developed through which phosphogypsum and red mud can be transformed into a precursor for the synthesis of high-strength, alkali-activated materials with a seawater-bearing sodium silicate solution as the alkaline activator. The effects of the activator modulus and liquid-to-solid ratio on the strength evolution of the synthesized AAMs as well as the microstructure and chemistry of the reaction products were investigated. The results showed that mineral reconstruction between PG and RM took place during calcination at 950 °C, forming ye'elimite, anhydrite and gehlenite, which then took part in the alkali-activation process and generated thenardite and C-A-S-H gel. The mechanical properties of the synthesized AAMs, ranging from 12.9 MPa to 40.6 MPa, were determined with the activator modulus and liquid-to-solid ratio. Results from the present investigation contributed to the facile and efficient valorization of phosphogypsum and red mud into cementitious construction materials.

15.
Materials (Basel) ; 16(9)2023 May 06.
Article in English | MEDLINE | ID: mdl-37176453

ABSTRACT

The development of sustainable cementitious materials is essential and urgent for the construction industry. Benefiting from excellent engineering properties and a reduced greenhouse gas footprint, alkali-activated materials (AAM) are among the robust alternatives to Portland cement for civil infrastructure. Meanwhile, concrete production also accounts for around 20% of all industrial water consumption, and the global freshwater shortage is increasing. This review discusses recent investigations on seawater-mixed AAMs, including the effects of seawater on workability, reaction mechanism, shrinkage, short and long-term strength, binding of chloride and corrosion of steel reinforcement. Attention is also paid to the utilization of sea sand as aggregate, as well as discussions on the challenges and further research perspectives on the field application of AAMs with seawater and sea sand.

16.
IEEE Trans Pattern Anal Mach Intell ; 45(7): 8453-8465, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37015427

ABSTRACT

Self-similarity is valuable to the exploration of non-local textures in single image super-resolution (SISR). Researchers usually assume that the importance of non-local textures is positively related to their similarity scores. In this paper, we surprisingly found that when repairing severely damaged query textures, some non-local textures with low-similarity which are closer to the target can provide more accurate and richer details than the high-similarity ones. In these cases, low-similarity does not mean inferior but is usually caused by different scales or orientations. Utilizing this finding, we proposed a Global Learnable Attention (GLA) to adaptively modify similarity scores of non-local textures during training instead of only using a fixed similarity scoring function such as the dot product. The proposed GLA can explore non-local textures with low-similarity but more accurate details to repair severely damaged textures. Furthermore, we propose to adopt Super-Bit Locality-Sensitive Hashing (SB-LSH) as a preprocessing method for our GLA. With the SB-LSH, the computational complexity of our GLA is reduced from quadratic to asymptotic linear with respect to the image size. In addition, the proposed GLA can be integrated into existing deep SISR models as an efficient general building block. Based on the GLA, we constructed a Deep Learnable Similarity Network (DLSN), which achieves state-of-the-art performance for SISR tasks of different degradation types (e.g., blur and noise). Our code and a pre-trained DLSN have been uploaded to GitHub† for validation.

17.
Ecotoxicol Environ Saf ; 258: 114955, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37121076

ABSTRACT

The effect of mean flow velocity on phosphorus (P) partitioning between water and sediment has received much attention in recent decades. However, the impact of turbulence on the efficiency and capability of sediment adsorbing and desorbing dissolved inorganic phosphorus (DIP) is still unclear. A series of contrasting experiments on the sediment sorption and desorption of DIP with the flow turbulence kinetic energy (TKE) ranging from 1.95 to 2.93 pa have been conducted. It was found that the adsorbed P onto unit mass of sediment increases with the increase in TKE. It is because an increase in TKE results in a rise in the effective adsorption capacity of sediment (bm) by 20-30% during the adsorption process. The bm shows the maximum rise from 0.18 to 0.25 mg/g when TKE increases from 1.95 to 2.93 pa with a fixed sediment concentration of 0.5 g/L. To account for the direct effect of TKE on P adsorption, the Langmuir model is modified by introducing a newly defined coefficient (fA-TKE). The fA-TKE shows a good linear relationship with TKE. Comparison between the modified model and the classic model shows that the amount of adsorbed P could be overestimated by over 50% if the direct effect of turbulence intensity is ignored. The experimental data show that the increase in TKE also enhances the desorption process, with the degree of P desorption (Ddes) increased by 44%. The relation between Ddes and TKE can be well represented using a logarithmic function to quantify the direct effect of turbulence intensity on desorption of P.


Subject(s)
Phosphorus , Water Pollutants, Chemical , Geologic Sediments , Adsorption , Water , Water Pollutants, Chemical/analysis
18.
Environ Res ; 226: 115639, 2023 06 01.
Article in English | MEDLINE | ID: mdl-36907348

ABSTRACT

Superabsorbent resin (SAR) saturated with heavy metals poses a threat to surrounding ecosystem. To promote the reutilization of waste, resins adsorbed by Fe2+ and Cu2+ were carbonized and used as catalysts (Fe@C/Cu@C) to activate persulfate (PS) for 2,4-dichlorophenol (2,4-DCP) degradation. The heterogeneous catalytic reaction was mainly responsible for 2,4-DCP removal. The synergistic effect of Fe@C and Cu@C was propitious to 2,4-DCP degradation. Fe@C/Cu@C with a ratio of 2:1 showed the highest performance of 2,4-DCP removal. 40 mg/L 2,4-DCP was completely removed within 90 min under reaction conditions of 5 mM PS, pH = 7.0 and T = 25 °C. The cooperation of Fe@C and Cu@C facilitated the redox cycling of Fe and Cu species to supply accessible PS activation sites, enhancing ROS generation for 2,4-DCP degradation. Carbon skeleton enhanced 2,4-DCP removal via radical/nonradical oxidation pathways and via its adsorption to 2,4-DCP. SO4˙-, HO˙ and O2•- were the dominate radical species involved in 2,4-DCP destruction. Meanwhile, the possible pathways of 2,4-DCP degradation were proposed based on GC-MS. Finally, recycling tests proved catalysts exhibited recyclable stability. Aiming to resource utilization, Fe@C/Cu@C with satisfactory catalysis and stability, is promising catalyst for contaminated water treatment.


Subject(s)
Chlorophenols , Water Pollutants, Chemical , Ecosystem , Phenols , Oxidation-Reduction , Metals , Water Pollutants, Chemical/analysis
19.
J Environ Manage ; 332: 117403, 2023 Apr 15.
Article in English | MEDLINE | ID: mdl-36738722

ABSTRACT

The complexity of municipal sludge dewatering is a bottleneck problem limiting resource utilization. In this paper, adding municipal solid waste incineration fly ash (MSWI FA) to municipal sludge for enhanced dewatering was applied, while the chlorine salt in MSWI FA was simultaneously removed using water in municipal sludge. The effects of different dosages and chemical components of MSWI FA on municipal sludge dewatering, and the removal effect of municipal sludge washing on Cl element were investigated. The results showed that the municipal sludge's specific resistance to filtration after co-treatment was significantly reduced, and more hydrophobic channels were formed in the vacuum suction filtration of the treated municipal sludge, conducive to efficient water removal. The moisture content of municipal sludge was reduced from 96.0% to 48.3%, and the moisture reduction rate increased from 17.7% to 32.1%. The chemical composition of MSWI FA could effectively promote the dewatering of municipal sludge, among which CaO was the best, followed by CaCl2 and NaCl, and KCl was the worst. Simultaneously, the municipal sludge showed a good effect on removing Cl from MSWI FA. The minimum Cl content in the mixture after Co-treatment is 1.5%. These results could provide a new way to dispose of MSWI FA and municipal sludge.


Subject(s)
Metals, Heavy , Refuse Disposal , Incineration , Coal Ash , Solid Waste , Sewage , Particulate Matter , Metals, Heavy/chemistry , Carbon/chemistry , Chlorine/chemistry , Chlorides , Sodium Chloride , Water
20.
ACS Nano ; 17(3): 3194-3203, 2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36724114

ABSTRACT

The huge amount of degraded NCM (LiNi0.5Co0.2Mn0.3O2) cathode materials from spent lithium-ion batteries is arising as a serious environmental issue as well as a severe waste of metal resources, and therefore, direct recycling of them toward usable electrode materials again is environmentally and economically more attractive in contrast to present metallurgical treatments. In this work, we design a robust two-step method for direct recycling of degraded NCM materials, which uses the aluminum impurity from the attached current collector to supplement the transition metal vacancies for simultaneous elemental compensation and structural restoration. This single-element compensation strategy leads to the regeneration of high-quality NCM material with depressed cation disordering and stabilized layered structure. Moreover, the regenerated NCM material with controllable Al doping delivered an outstanding electrochemical performance; specifically, the capacity (158.6 mAh g-1), rate capability (91.6 mAh g-1 at 5 C), and cycling stability (89.6% capacity retention after 200 cycles) of the regenerated NCM material are even comparable with those of fresh materials. The as-established regeneration protocol has its chance in simplifying the industrial recycling process of degraded NCM materials.

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