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1.
J Environ Sci (China) ; 147: 230-243, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003043

RESUMO

Enhancing soil organic matter characteristics, ameliorating physical structure, mitigating heavy metal toxicity, and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings substrate to a soil-like substrate. The incorporation of biomass co-pyrolysis and plant colonization has been established to be a significant factor in soil substrate formation and soil pollutant remediation. Despite this, there is presently an absence of research efforts aimed at synergistically utilizing these two technologies to expedite the process of mining tailings soil substrate formation. The current study aimed to investigate the underlying mechanism of geochemical changes and rapid mineral weathering during the process of transforming tailings substrate into a soil-like substrate, under the combined effects of biomass co-smoldering pyrolysis and plant colonization. The findings of this study suggest that the incorporation of smoldering pyrolysis and plant colonization induces a high-temperature effect and biological effects, which enhance the physical and chemical properties of tailings, while simultaneously accelerating the rate of mineral weathering. Notable improvements include the amelioration of extreme pH levels, nutrient enrichment, the formation of aggregates, and an increase in enzyme activity, all of which collectively demonstrate the successful attainment of tailings substrate reconstruction. Evidence of the accelerated weathering was verified by phase and surface morphology analysis using X-ray diffraction and scanning electron microscopy. Discovered corrosion and fragmentation on the surface of minerals. The weathering resulted in corrosion and fragmentation of the surface of the treated mineral. This study confirms that co-smoldering pyrolysis of biomass, combined with plant colonization, can effectively promote the transformation of tailings into soil-like substrates. This method has can effectively address the key challenges that have previously hindered sustainable development of the mining industry and provides a novel approach for ecological restoration of tailings deposits.


Assuntos
Biomassa , Mineração , Poluentes do Solo , Solo , Solo/química , Pirólise , Plantas , Biodegradação Ambiental
2.
J Hazard Mater ; 480: 135811, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39298947

RESUMO

Air pollution is one of the major environmental risks threatening human health, diesel exhaust particulate matter (DEPM) is an important source of urban air pollution, and oral ingestion is the primary route of exposure to atmospheric particulate matter. This study examined the bioaccessibility of Cr, Fe, and Zn in DEPM within simulated saliva fluids through in vitro experiments, interactions between the particles and mucins, and the mechanisms underlying the oxidative damage they cause. The results indicated that the interaction between DEPM and mucins altered the dispersibility, surface charge, and wettability of the particles, leading to increased release of heavy metals. Protein adsorption experiments and characterizations revealed that the adsorption of mucin by the particles resulted in a complexation reaction between the metals in the DEPM and the mucins, accompanied by fluorescence quenching of the protein. In addition, free radical assays and correlation analyses revealed that environmentally persistent free radicals generated by DEPM induce the production of reactive oxygen species (O2·-, HOOH, and·OH), which damage the secondary structure of mucins and increase the risk of oral diseases. Our study is the first to reveal the interaction between DEPM and mucins in saliva, elucidating the mechanisms of DEPM-induced oxidative damage. This is significant for understanding the oral health risks posed by the ingestion of atmospheric particulate matter.

3.
Chemosphere ; 362: 142669, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38906186

RESUMO

Exposure to ozone (O3) and nitrogen dioxide (NO2) are related to pulmonary dysfunctions and various lung diseases, but the underlying biochemical mechanisms remain uncertain. Herein, the effect of inhalable oxidizing gas pollutants on the pulmonary surfactant (PS, extracted from porcine lungs), a mixture of active lipids and proteins that plays an important role in maintaining normal respiratory mechanics, is investigated in terms of the interfacial chemistry using in-vitro experiments; and the oxidative stress induced by oxidizing gases in the simulated lung fluid (SLF) supplemented with the PS is explored. The results showed that O3 and NO2 individually increased the surface tension of the PS and reduced its foaming ability; this was accompanied by the surface pressure-area isotherms of the PS monolayers shifting toward lower molecular areas, with O3 exhibiting more severe effects than NO2. Moreover, both O3 and NO2 produced reactive oxygen species (ROS) resulting in lipid peroxidation and protein damage to the PS. The formation of superoxide radicals (O2•-) was correlated with the decomposition of O3 and the reactions of O3 and NO2 with antioxidants in the SLF. These radicals, in the presence of antioxidants, led to the formation of hydrogen peroxide and hydroxyl radicals (•OH). Additionally, the direct oxidation of unsaturated lipids by O3 and NO2 further caused an increase in the ROS content. This change in the ROS chemistry and increased •OH production tentatively explain how inhalable oxidizing gases lead to oxidative stress and adverse health effects. In summary, our results indicated that inhaled O3 and NO2 exposure can significantly alter the interfacial properties of the PS, oxidize its active ingredients, and induce ROS formation in the SLF. The results of this study provide a basis for the elucidation of the potential hazards of inhaled oxidizing gas pollutants in the human respiratory system.


Assuntos
Pulmão , Dióxido de Nitrogênio , Estresse Oxidativo , Ozônio , Surfactantes Pulmonares , Espécies Reativas de Oxigênio , Estresse Oxidativo/efeitos dos fármacos , Animais , Surfactantes Pulmonares/química , Suínos , Dióxido de Nitrogênio/química , Ozônio/química , Ozônio/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/química , Peroxidação de Lipídeos/efeitos dos fármacos , Antioxidantes/química , Oxirredução
4.
Adv Sci (Weinh) ; 11(28): e2402892, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757555

RESUMO

Rechargeable Li-CO2 batteries are considered as a promising carbon-neutral energy storage technology owing to their ultra-high energy density and efficient CO2 capture capability. However, the sluggish CO2 reduction/evolution kinetics impedes their practical application, which leads to huge overpotentials and poor cyclability. Multi-element transit metal oxides (TMOs) are demonstrated as effective cathodic catalysts for Li-CO2 batteries. But there are no reports on the integration of defect engineering on multi-element TMOs. Herein, the oxygen vacancy-bearing Li-Ni-Co-Mn multi-oxide (Re-NCM-H3) catalyst with the α-NaFeO2-type structure is first fabricated by annealing the NiCoMn precursor that derived from spent ternary LiNi0.8Co0.1Mn0.1O2 cathode, in H2 at 300 °C. As demonstrated by experimental results and theory calculations, the introduction of moderate oxygen vacancy has optimized electronic state near the Fermi level (Ef), eventually improving CO2 adsorption and charge transfer. Therefore, the Li-CO2 batteries with Re-NCM-H3 catalyst deliver a high capacity (11808.9 mAh g-1), a lower overpotential (1.54 V), as well as excellent stability over 216 cycles at 100 mA g-1 and 165 cycles at 400 mA g-1. This study not only opens up a sustainable application of spent ternary cathode, but also validates the potential of multi-element TMO catalysts with oxygen defects for high-efficiency Li-CO2 batteries.

5.
J Hazard Mater ; 472: 134490, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38696963

RESUMO

Air pollution by sulfur dioxide (SO2) remains a pressing concern for both the environment and human health. Desulfurization enhanced by persulfate based advanced oxidation processes (PS-AOPs) has been proven to be a feasible method. However, the inherent contradiction between the rapid diffusion mass transfer of SO2 in the "gas-liquid-gas" phase and the limited lifespan of reactive oxygen species (ROS) can not be ignored. Excessive investment in PS is required to sustainably generate ROS to achieve continuous desulfurization performance, which may lead to excessive PS consumption. To address this issue, whether PS can achieve the oxidation absorption of SO2 via a non-reactive oxygen species pathway was investigated. Experimental and computational results demonstrated that peroxymonosulfate (PMS) instead of peroxydisulfate (PDS) had a great SO2 removal performance, the utilization of PS could be effectively achieved by maintaining a 1:1 molar ratio of PMS and removed SO2. The presence of HOO bonds in the PMS introduced a partial positive charge to the oxygen atom, making the PMS polar and more susceptible to be attacked by the nucleophile HSO3-. So SO2 underwent a series of processes including dissolution, dissociation, one-oxygen atom transfer, and ionization before ultimately being converted into SO42- ions, effectively achieving its removal from flue gas. This study may presents a novel approach for achieving high-efficiency flue gas desulfurization.

6.
Environ Res ; 250: 118498, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382665

RESUMO

Soil heavy metal pollution is an important issue that affects human health and ecological well-being. In-situ thermal treatment techniques, such as self-sustaining smoldering combustion (SSS), have been widely studied for the treatment of organic pollutants. However, the lack of fuel in heavy metal-contaminated soil has hindered its application. In this study, we used corn straw as fuel to investigate the feasibility of SSS remediation for copper and lead in heavy metal-contaminated soil, as well as to explore the remediation mechanism. The results of the study showed that SSS increased soil pH, electrical conductivity (EC), total phosphorus (TP), total potassium (TK), rapidly available phosphorus (AP), and available potassium (AK), while decreasing total nitrogen (TN), alkali-hydrolyzed nitrogen (AN), and cation exchange capacity (CEC). The oxidation state of copper (Cu) increased from 10% to 21%-40%, and the residual state of lead (Pb) increased from 18% to 51%-73%. The Toxicity characteristic leaching procedure (TCLP) of Cu decreased by a maximum of 81.08%, and the extracted state of Diethylenetriaminepentaacetic acid (DTPA) decreased by 67.63%; the TCLP of Pb decreased by a maximum of 81.87%, and DTPA decreased by a maximum of 85.68%. The study indicates that SSS using corn straw as fuel successfully achieved remediation of heavy metal-contaminated soil. However, SSS does not reduce the content of copper and lead; it only changes their forms in the soil. The main reasons for the fixation of copper and lead during the SSS process are the adsorption of biochar, complexation with -OH functional groups, binding with π electrons, and the formation of crystalline compounds. This research provides a reference for the application of SSS in heavy metal-contaminated soil and has potential practical implications.


Assuntos
Cobre , Recuperação e Remediação Ambiental , Estudos de Viabilidade , Chumbo , Poluentes do Solo , Cobre/química , Cobre/análise , Chumbo/análise , Chumbo/química , Poluentes do Solo/análise , Poluentes do Solo/química , Recuperação e Remediação Ambiental/métodos , Zea mays/química , Solo/química
7.
J Mol Model ; 30(1): 21, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170322

RESUMO

CONTEXT: The hydrogen cyanide (HCN) hydrolysis reaction mechanism over Al-doped graphene was investigated through the density functional theory method. HCN preferentially adsorbed vertically on the Al top site to form a stable adsorption configuration. H2O preferentially adsorbed parallel on the Al top site to form a stable adsorption configuration. The competitive adsorption of HCN and H2O weakened the adsorption stability of each molecule over Al-doped graphene. The break of C-N and H-O bonds was the key process in the preferential fracture pathway of the C-H bond. The break of C-N and C-H bonds was the key process in the preferential fracture pathway of the H-O bond. HCN played the role of bridge in the joint adsorption process. H atom transfer and C-N bond cleavage promoted the generation of CO and NH3. The change in the order of H atom transfer determined the reaction energy barrier. NH2CHO was more likely to act as an intermediate to promote the hydrolysis process. METHODS: The calculation work was achieved from the Dmol3 program in Material Studio 2017 using the GGA/PBE method with DNP basis, including the geometric structure and reaction pathway optimization, and adsorption energy calculation. All calculations were performed using a spin-polarized set and the TS method was used for DFT-D correction.

8.
Environ Sci Pollut Res Int ; 31(10): 15398-15411, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38294651

RESUMO

The study is about the size distribution and health risks of polycyclic aromatic hydrocarbons (PAHs) in indoor environment of Xuanwei, Southwest China particle samples were collected by Anderson 8-stage impactor which was used to gather particle samples to nine size ranges. Size-segregated samples were collected in indoor from a rural village in Xuanwei during the non-heating and heating seasons. The results showed that the total concentrations of the indoor particulate matter (PM) were 757 ± 60 and 990 ± 78 µg/m3 in non-heating and heating seasons, respectively. The total concentration of indoor PAHs reached to 8.42 ± 0.53 µg/m3 in the heating season, which was considerably greater than the concentration in the non-heating season (2.85 ± 1.72 µg/m3). The size distribution of PAHs showed that PAHs were mainly enriched in PMs with the diameter <1.1 µm. The diagnostic ratios (DR) and principal component analysis (PCA) showed that coal and wood for residential heating and cooking were the main sources of indoor PAHs. The results of the health risk showed that the total deposition concentration (DC) in the alveolar region (AR) was 0.25 and 0.68 µg/m3 in the non-heating and heating seasons respectively. Throughout the entire sampling periods, the lifetime cancer risk (R) based on DC of children and adults varied between 3.53 ×10-5 to 1.79 ×10-4. During the heating season, the potential cancer risk of PAHs in adults was significant, exceeding 10-4, with a rate of 96%.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Criança , Humanos , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição do Ar em Ambientes Fechados/análise , Material Particulado/análise , Poeira/análise , China , Carvão Mineral/análise
9.
Environ Res ; 245: 117803, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38043900

RESUMO

The relationship between microplastics (MPs) and human respiratory health has garnered significant attention since inhalation constitutes the primary pathway for atmospheric MP exposure. While recent studies have revealed respiratory risks associated with MPs, virgin MPs used as plastic surrogates in these experiments did not represent the MPs that occur naturally and that undergo aging effects. Thus, the effects of aged MPs on respiratory health remain unknown. We herein analyzed the interaction between inhalable aged MPs with lung surfactant (LS) extracted from porcine lungs vis-à-vis interfacial chemistry employing in-vitro experiments, and explored oxidative damage induced by aged MPs in simulated lung fluid (SLF) and the underlying mechanisms of action. Our results showed that aged MPs significantly increased the surface tension of the LS, accompanied by a diminution in its foaming ability. The stronger adsorptive capacity of the aged MPs toward the phospholipids of LS appeared to produce increased surface tension, while the change in foaming ability might have resulted from a variation in the protein secondary structure and the adsorption of proteins onto MPs. The adsorption of phospholipid and protein components then led to the aggregation of MPs in SLF, where the aged MPs exhibited smaller hydrodynamic diameters in comparison with the unaged MPs, likely interacting with biomolecules in bodily fluids to exacerbate health hazards. Persistent free radicals were also formed on aged MPs, inducing the formation of reactive oxygen species such as superoxide radicals (O2•-), hydrogen peroxide (HOOH), and hydroxyl radicals (•OH); this would lead to LS lipid peroxidation and protein damage and increase the risk of respiratory disease. Our investigation was the first-ever to reveal a potential toxic effect of aged MPs and their actions on the human respiratory system, of great significance in understanding the risk of inhaled MPs on lung health.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Suínos , Humanos , Idoso , Plásticos/toxicidade , Pulmão/metabolismo , Estresse Oxidativo , Tensoativos , Poluentes Químicos da Água/metabolismo
10.
Front Public Health ; 11: 1270033, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045962

RESUMO

Background: The intricate interplay between human well-being and the surrounding environment underscores contemporary discourse. Within this paradigm, comprehensive environmental monitoring holds the key to unraveling the intricate connections linking population health to environmental exposures. The advent of satellite remote sensing monitoring (SRSM) has revolutionized traditional monitoring constraints, particularly limited spatial coverage and resolution. This innovation finds profound utility in quantifying land covers and air pollution data, casting new light on epidemiological and geographical investigations. This dynamic application reveals the intricate web connecting public health, environmental pollution, and the built environment. Objective: This comprehensive review navigates the evolving trajectory of SRSM technology, casting light on its role in addressing environmental and geographic health issues. The discussion hones in on how SRSM has recently magnified our understanding of the relationship between air pollutant exposure and population health. Additionally, this discourse delves into public health challenges stemming from shifts in urban morphology. Methods: Utilizing the strategic keywords "SRSM," "air pollutant health risk," and "built environment," an exhaustive search unfolded across prestigious databases including the China National Knowledge Network (CNKI), PubMed and Web of Science. The Citespace tool further unveiled interconnections among resultant articles and research trends. Results: Synthesizing insights from a myriad of articles spanning 1988 to 2023, our findings unveil how SRMS bridges gaps in ground-based monitoring through continuous spatial observations, empowering global air quality surveillance. High-resolution SRSM advances data precision, capturing multiple built environment impact factors. Its application to epidemiological health exposure holds promise as a pioneering tool for contemporary health research. Conclusion: This review underscores SRSM's pivotal role in enriching geographic health studies, particularly in atmospheric pollution domains. The study illuminates how SRSM overcomes spatial resolution and data loss hurdles, enriching environmental monitoring tools and datasets. The path forward envisions the integration of cutting-edge remote sensing technologies, novel explorations of urban-public health associations, and an enriched assessment of built environment characteristics on public well-being.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Humanos , Tecnologia de Sensoriamento Remoto , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Exposição Ambiental , Ambiente Construído
11.
Sci Total Environ ; 905: 167177, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730037

RESUMO

The use of persulfate (PDS) for in-situ chemical oxidation of organic contaminants in soils has garnered significant interest. However, the presence of naturally occurring iron-containing substances and humic acid (HA) in environmental compartments can potentially influence the effectiveness of soil remediation. Thus, this study aimed to investigate the role of key functional groups (adjacent phenolic hydroxyl (Ar-OH) and carboxyl groups (-COOH)) in HA that interact with iron. Modified HAs were used to confirm the significance of these moieties in iron interaction. Additionally, the mechanism by which specific functional groups affect Fe complexation and redox was explored through contaminant degradation experiments, pH-dependent investigations, HA by-products analysis, and theoretical calculations using six specific hydroxybenzoic acids as HA model compounds. The results showed a strong positive correlation between accessible Ar-OH and -COOH groups and Fe3+/Fe2+ redox. This was attributed to HA undergoing a conversion process to a semiquinone-containing radical form, followed by a quinone-containing intermediate, while Fe3+ acted as an electron shuttle between HA and PDS, with Fe3+ leaching facilitated by generated H+ ions. Although the stability of HA-Fe3+ complexes with -COOH as the primary binding sites was slightly higher at neutral/alkaline conditions compared to acidic conditions, the buffering properties of the soil and acidification of the PDS solution played a greater role in determining the Ar-OH groups as the primary binding site in most cases. Therefore, the availability of Ar-OH groups on HA created a trade-off between accelerated Fe3+/Fe2+ redox and quenching reactions. Appropriate HA and iron contents were found to favor PDS activation, while excessive HA could lead to intense competition for reactive oxygen species (ROS), inhibiting pollutant degradation in soil. The findings provide valuable insights into the interaction of HA and Fe-containing substances in persulfate oxidation, offering useful information for the development of in-situ remediation strategies for organic-contaminated soil.

12.
Sci Total Environ ; 903: 166285, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37586511

RESUMO

Copper oxide nanoparticles (CuO NPs) can adversely affect lung health possibly by inducing oxidative damage through the release of copper ions. However, the migration and transformation processes of CuO NPs in lung lining fluid is still unclear, and there are still conflicting reports of redox reactions involving copper ions. To address this, we examined the release of copper ions from CuO NPs in simulated lung fluid supplemented with pulmonary surfactant (PS), and further analyzed the mechanisms of PS-CuO NPs interactions and the health hazards. The results showed that the phospholipid of PS was adsorbed on the particle surface, which not only induced aggregation of the particles but also provided a reaction environment for the interaction of PS with CuO NPs. PS was able to promote the release of ions from CuO NPs, of which the protein was a key component. Lipid peroxidation, protein destabilization, and disruption of the interfacial chemistry also occurred in the PS-CuO NPs interactions, during which copper ions were present only as divalent cations. Meanwhile, the contribution of the particle surface cannot be neglected in the oxidative damage to the lung caused by CuO NPs. Through reacting with biomolecules, CuO NPs accomplished ion release and induced oxidative damage associated with PS. This research was the first to reveal the mechanism of CuO NPs releasing copper ions and inducing lipid oxidative damage in the presence of PS, which provides a new idea of transition metal-induced health risk in human body.

13.
J Environ Manage ; 344: 118469, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37393878

RESUMO

The total de-alkalization treatment of industrial solid waste red mud (RM) has been a worldwide challenge. Removing the insoluble structural alkali fraction from RM is the key to enhancing the sustainable utilization of RM resources. In this paper, supercritical water (SCW) and leaching agents were used for the first time to de-alkalize the Bayer RM and to remove sulfur dioxide (SO2) from flue gas with the de-alkalized RM slurry. The results showed that the optimum alkali removal and Fe leaching rates of RM-CaO-SW slurry were 97.90 ± 0.88% and 82.70 ± 0.95%, respectively. Results confirmed that the SCW technique accelerated the disruption of (Al-O) and (Si-O) bonds and the structural disintegration of aluminosilicate minerals, facilitating the conversion of insoluble structural alkalis to soluble chemical alkalis. The exchangeable Ca2+ displaced Na+ in the remaining insoluble base, producing soluble sodium salts or alkalis. CaO consumed SiO2, which was tightly bound to Fe2O3 in RM, and released Fe2O3, which promoted Fe leaching. RM-SCW showed the best desulfurization performance, which maintained 88.99 ± 0.0020% at 450 min, followed by RM-CaO-SW (450 min, 60.75 ± 6.00%) and RM (180 min, 88.52% ± 0.00068). The neutralization of alkaline components, the redox of metal oxides, and the liquid-phase catalytic oxidation of Fe contributed to the excellent desulfurization performance of the RM-SCW slurry. A promising approach shown in this study is beneficial to RM waste use, SO2 pollution control, and sustainable growth of the aluminum industry.


Assuntos
Dióxido de Silício , Água , Água/química , Resíduos Industriais , Alumínio , Óxidos
14.
Chemosphere ; 337: 139330, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37364645

RESUMO

Dissolved black carbon (DBC), an important photosensitizer in surface waters, can influence the photodegradation of various organic micropollutants. In natural water systems, DBC often co-occurs with metal ions as DBC-metal ion complexes; however, the influence of metal ion complexation on the photochemical activity of DBC is still unclear. Herein, the effects of metal ion complexation were investigated using common metal ions (Mn2+, Cr3+, Cu2+, Fe3+, Zn2+, Al3+, Ca2+, and Mg2+). Complexation constants (logKM) derived from three-dimensional fluorescence spectra revealed that Mn2+, Cr3+, Cu2+, Fe3+, Zn2+, and Al3+ quenched the fluorescence components of DBC via static quenching. The steady-state radical experiment suggested that in the complex systems of DBC with various metal ions, Mn2+, Cr3+, Cu2+, Fe3+, Zn2+ and Al3+ inhibited the photogeneration of 3DBC* via dynamic quenching, which reduced the yields of 3DBC*-derived 1O2 and O2·-. Moreover, 3DBC* quenching by metal ions was associated with the complexation constant. A strong positive linear relationship existed between logKM and the dynamic quenching rate constant of metal ions. These results indicate that the strong complexation ability of metal ions enabled 3DBC quenching, which highlights the photochemical activity of DBC in natural aquatic environments enriched with metal ions.


Assuntos
Metais , Água , Metais/química , Íons , Fotólise , Carbono
15.
Chemosphere ; 334: 138936, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37182711

RESUMO

Self-sustaining smoldering is an emerging technology for nonaqueous-phase liquid remediation; however, it is rarely applied for Cr(VI)-contaminated soil treatment. In this study, self-sustaining smoldering using rice straw (RS) as a surrogate fuel was applied to remediate Cr(VI)-contaminated soil for the first time. Thirteen one-dimensional vertical smoldering experiments were conducted to investigate the effectiveness of the smoldering method and the effects of key experimental parameters on smoldering remediation performance. Smoldering was observed to be self-sustaining within the range of RS particle size from <0.16 to 2.00-4.00 mm, airflow from 0.2 to 1 m3/h, and Cr(VI)-impacted soil/RS ratios from 2:1 to 6:1. The Cr(VI)-contaminated soil was effectively remediated, which was confirmed by lowered Cr(VI) contents in the treated samples (decreased by 52.22-86.57%) and the elevated fraction of Cr oxidizable and residual form (increased by 1.14-3.30 and 2.97-4.00 times, respectively), compared to the control. The reducing gases (CO and CxHy) generated during the smoldering played a crucial role in the remediation process. The contents of available P and K in the remediated soil containing the remaining biochar and ash increased, thus improving soil reusability. Hence, this study shows that smoldering with RS as supplemental fuel is a promising Cr(VI)-contaminated soil management technique without supplying substantial external energy.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Cromo/análise , Poluição Ambiental , Solo , Poluentes do Solo/análise
16.
Heliyon ; 9(1): e12146, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685456

RESUMO

In order to investigate the difference of volatile substances among flavored cigarette paper, which are supplied by several manufacturers with different batches, the stability of the complex system of scented cigarette paper was analyzed and evaluated. In this study, Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was used to detect the aroma compounds of 23 flavored cigarette paper samples. Based on fingerprint analysis, the differences and changes of aroma compounds of different samples were studied in the form of data visualization. Principal component analysis, partial least squares regression analysis, cluster heatmap analysis and artificial neural network analysis were used to evaluate the stability of different cigarette paper. The results show that: A total of 29 volatile substances were identified from different scented cigarette paper. Fingerprint analysis revealed that the volatile substances of different cigarette paper samples were roughly the same, but not the content. The results of chemometrics analysis showed that there were significant differences in the characteristic aroma compounds of cigarette paper from different manufacturers. HS-GC-IMS technology combined with chemometrics method could be applied to determine the difference of volatile substances among different flavored cigarette paper, which theoretically and technically supported the quality stability maintenance and identification of flavored cigarette paper processed in different places.

17.
Basic Clin Androl ; 32(1): 18, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36324079

RESUMO

BACKGROUND: Sperm cryopreservation is an effective method of fertility preservation for disease-related and social sperm freezing. In total, 662 subjects (range: 15-65 years-of-age; mean: 33.49 ± 8.79 years-of-age) were included in this study to investigate the population characteristics, semen quality, and usage of autologous sperm preservation patients in Beijing. Of these, 351 were cancer patients (53.02%, 31.14 ± 7.32 years-of-age) and 311 were non-cancer patients (46.98%, 36.14 ± 9.54 years-of-age). RESULTS: We found that the number of preservation cases increased steadily from 2015 to 2019; 89.73% of these had a bachelor's degree or above; 54.83%, 41.54%, and 3.63% were single, married, and divorced, respectively. The cases of cancers and oligozoospermia accounted for 71.30% of all patients; therefore, most patients required fertility preservation due to disease. The cancer group had a significantly lower sperm concentration, rate of progressive sperm after the frozen-thawed test, total progressive motility sperm count after the frozen-thawed test, and recovery rate of progressive motile sperm (RRPM) than the non-cancer group (all P < 0.05). Sperm count-related parameters were significantly affected by testicular cancer, while sperm motility-related parameters and RRPM were significantly affected by leukemia. The utilization rate of preserved sperm was 6.34% after 6 to 78 months of follow-up. In terms of fresh or frozen embryo transfer, the clinical pregnancy rate was 56.76% or 50.00%, and the live birth rate was 24.32% or 21.43%, respectively. CONCLUSION: The need for autologous sperm preservation was dominated by patients with diseases, followed by the need for social sperm freezing. Tumors had a major negative impact on semen quality, and the usage rates of stored semen were at lower level compared to the number of sperm cryopreservation. Medical staff and patients should pay attention to both cognition-action consistency and cost-effectiveness in fertility preservation.


RéSUMé: CONTEXTE: La cryoconservation des spermatozoïdes est une méthode efficace de préservation de la fertilité pour la congélation des spermatozoïdes liée à des causes médicales et aux demandes sociétales. Au total, 662 hommes (entre 15 et 65 ans; moyenne: 33,5 ± 8,8 ans) ont été inclus dans cette étude pour évaluer les caractéristiques de la population, la qualité du sperme et l'utilisation de la préservation autologue de spermatozoïdes réalisée par des patients à Beijing. Parmi ceux-ci, 351 étaient des patients atteints de cancer (53%; 31,1 ± 7,3 ans) et 311 des patients non atteints de cancer (47%; 36,1 ± 9,5 ans). RéSULTATS: Nous avons constaté que le nombre de cas de conservation a augmenté régulièrement de 2015 à 2019; 89,7% d'entre eux avaient un baccalauréat ou plus; 54,8%, 41,5% et 3,6% étaient respectivement célibataires, mariés, ou divorcés. Les cas de cancer et ceux d'oligozoospermie représentaient 71,3% de tous les patients; par conséquent, la plupart des patients avaient besoin d'une préservation de la fertilité pour raison de maladie. Le groupe des hommes atteints de cancer avait significativement une plus faible concentration de spermatozoïdes, un plus faible taux de spermatozoïdes progressifs après le test de congelation-décongelation, un plus faible nombre total de spermatozoïdes de motilité progressive après le test de congelation-décongelation, et un plus faible taux de récupération de spermatozoïdes mobiles progressifs (TRMP) que le groupe de patients non atteints de cancer (tous p < 0,05). Les paramètres liés au nombre de spermatozoïdes ont été significativement affectés par le cancer du testicule, tandis que les paramètres liés à la mobilité des spermatozoïdes et le taux de récupération de spermatozoïdes mobiles progressifs ont été significativement affectés par la leucémie. Le taux d'utilisation des spermatozoïdes conservés était de 6,3% après 6 à 78 mois de suivi. En ce qui concerne le transfert d'embryons frais et congelés, le taux de grossesse clinique était respectivement de 56,8% et 50,0%, et le taux de naissances vivantes respectivement de 24,3% et 21,4%. CONCLUSIONS: Le besoin de conservation autologue des spermatozoïdes était dominé par les patients atteints de maladies, suivi par le besoin social de congélation des spermatozoïdes. Les tumeurs ont eu un impact négatif majeur sur la qualité du sperme, et le taux d'utilisation des spermatozoïdes stockés était à un niveau inférieur à celui du nombre de cryoconservation des spermatozoïdes. Le personnel médical et les patients doivent prêter attention à la fois à la cohérence cognition-action et à la rentabilité de la préservation de la fertilité.

18.
Environ Technol ; : 1-11, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35946505

RESUMO

Acid mine drainage (AMD) has caused a great impact on soil, surface water, groundwater, plants or other organisms in the mining environment because of its high acidity, high sulphate content, and contains a variety of heavy metals. AMD treated by carbonate rocks have been regarded as a feasible technology for pollution control and applied widely in mine area. However, to date, the kinetics of the reaction between carbonate rock and AMD have not been investigated, resulting in the lack of systematic theoretical guidance for the implementation of this technology. In this study, effects of carbonate particle sizes and reaction temperature on AMD treatment were investigated. The dissolution efficiency of Ca2+ was used to quantitatively reflect extent of reaction, and the leaching kinetics was analysed based on the shrinking core model. The results showed that carbonate rocks with a particle size of 0.5-1.0 mm had the best pH-enhancing performance for AMD and highest removal efficiency for Fe3+ (>98.00%), while the Mn2+ and SO42- were temperature sensitive. The diffusion of solid product layer was the controlling step of the leaching reaction, and the apparent activation energy of the reaction was 12.63 kJ·mol-1.

19.
Chemosphere ; 307(Pt 3): 135968, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35964723

RESUMO

Excited-triplet dissolved black carbon (DBC) was deemed as a significant reactive intermediate in the phototransformation of environmental micropollutants, but the impacts of concomitant metal ions on photochemical behavior of excited-triplet DBC (3DBC*) are poorly understood. Here, the photolytic kinetics of sulfadiazine and carbamazepine induced by 3DBC* involving Cu2+ was explored. The presence of Cu2+ reduced the 3DBC*-induced photodegradation rate of sulfadiazine; whereas for carbamazepine, Cu2+ enhanced 3DBC*-induced photodegradation. Cu(II)-DBC complex was formed due to the decreasing fluorescence intensities of DBC in the presence of Cu2+. Cu2+ complexation caused the decrease of 3DBC* steady-state concentrations, which markedly reduced 3DBC*-induced photodegradation rate of sulfadiazine due to its high triplet reactivity. Kinetic model showed that 3DBC* quenching rate by Cu2+ was 7.98 × 109 M-1 s-1. Cu2+ complexation can also enhance the electron transfer ability, thereby producing more ∙OH in Cu(II)-DBC complex, which explains the promoting effect of Cu2+ complexation on carbamazepine photodegradation in view of its low triplet reaction rate. These indicate that 3DBC* reactivity differences of organic micropollutants may explain their photodegradation kinetics differences in DBC system with/without Cu2+, which was supported by the linearized relationship between the photodegradation rate ratios of ten micropollutants with/without Cu2+ and their triplet reaction activity.


Assuntos
Cobre , Poluentes Químicos da Água , Carbamazepina , Carbono , Fotólise , Fuligem , Sulfadiazina , Poluentes Químicos da Água/análise
20.
Front Public Health ; 10: 844541, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480591

RESUMO

Aim: Evidence on the association between natural-built environments and depression is largely derived from the general population and prone to residential self-selection bias because of the nature of cross-sectional research design. Despite emerging adulthood, which includes the university years, is a critical stage for forming life-long health habits, studies on this topic focusing on undergraduate students are limited. The current study aims to illustrate the underlying mechanisms for how the campus-based environments affect depression in undergraduate students. Methods: Based on a nationwide representative analytical sample of 22,009 Chinese undergraduates in 2018, we examined participants' reports of depression and campus-centered natural/built environments within multiple buffer sizes including 0.5, 1.0, and 2.5 km. After disentangling residential self-selection, we explored the moderating role of the socioeconomic attributes of undergraduates. The depression outcome was measured by the nine-item Patient Health Questionnaire (PHQ9). Indicators of exposure to green and blue space, transportation infrastructure, and food environments were objectively assessed using different circular buffers around each campus address. Results: Modeling results indicated that campus neighborhoods with more scattered trees (0.5 km), water (0.5, 1.0, and 2.5 km), and street intersections (1.0 and 2.5 km) were protective against depression. In contrast, those living near denser distributions of outlets serving take-away sweets and fast food (0.5, 1.0, and 2.5 km) were susceptible to depression. These associations were modified by undergraduates' socioeconomic attributes (e.g., grade, Hukou status, and ethnicity) and varied according to geographical scales and exposure metrics. Conclusion: To deliver effective environmental interventions to curb the prevalence of depression among undergraduate students, further planning policies should focus on the careful conception of the campus-based environment, especially regarding different spatial scales.


Assuntos
Ambiente Construído , Depressão , Adulto , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Humanos , Fatores Socioeconômicos , Estudantes
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