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1.
J Environ Sci (China) ; 147: 153-164, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003036

RESUMEN

Heavy metal(loid) (HM) pollution in agricultural soils has become an environmental concern in antimony (Sb) mining areas. However, priority pollution sources identification and deep understanding of environmental risks of HMs face great challenges due to multiple and complex pollution sources coexist. Herein, an integrated approach was conducted to distinguish pollution sources and assess human health risk (HHR) and ecological risk (ER) in a typical Sb mining watershed in Southern China. This approach combines absolute principal component score-multiple linear regression (APCS-MLR) and positive matrix factorization (PMF) models with ER and HHR assessments. Four pollution sources were distinguished for both models, and APCS-MLR model was more accurate and plausible. Predominant HM concentration source was natural source (39.1%), followed by industrial and agricultural activities (23.0%), unknown sources (21.5%) and Sb mining and smelting activities (16.4%). Although natural source contributed the most to HM concentrations, it did not pose a significant ER. Industrial and agricultural activities predominantly contributed to ER, and attention should be paid to Cd and Sb. Sb mining and smelting activities were primary anthropogenic sources of HHR, particularly Sb and As contaminations. Considering ER and HHR assessments, Sb mining and smelting, and industrial and agricultural activities are critical sources, causing serious ecological and health threats. This study showed the advantages of multiple receptor model application in obtaining reliable source identification and providing better source-oriented risk assessments. HM pollution management, such as regulating mining and smelting and implementing soil remediation in polluted agricultural soils, is strongly recommended for protecting ecosystems and humans.


Asunto(s)
Agricultura , Antimonio , Monitoreo del Ambiente , Metales Pesados , Minería , Contaminantes del Suelo , Antimonio/análisis , Medición de Riesgo , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Monitoreo del Ambiente/métodos , China , Suelo/química
2.
J Environ Sci (China) ; 147: 370-381, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003055

RESUMEN

Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were screened. The surface of the bio-Fe/Mn oxides produced by the oxidation of Fe(II) and Mn(II) by Pseudomonas taiwanensis (marked as P4) and Pseudomonas plecoglossicida (marked as G1) contains rich reactive oxygen functional groups, which play critical roles in the removal efficiency and immobilization of heavy metal(loid)s in co-contamination system. The isolated strains P4 and G1 can grow well in the following environments: pH 5-9, NaCl 0-4%, and temperature 20-30°C. The removal efficiencies of Fe, Pb, As, Zn, Cd, Cu, and Mn are effective after inoculation of the strains P4 and G1 in the simulated water system (the initial concentrations of heavy metal(loid) were 1 mg/L), approximately reaching 96%, 92%, 85%, 67%, 70%, 54% and 15%, respectively. The exchangeable and carbonate bound As, Cd, Pb and Cu are more inclined to convert to the Fe-Mn oxide bound fractions in P4 and G1 treated soil, thereby reducing the phytoavailability and bioaccessible of heavy metal(loid)s. This research provides alternatives method to treat water and soil containing high concentrations of multi-heavy metal(loid)s.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes del Suelo/metabolismo , Oxidación-Reducción , Pseudomonas/metabolismo , Manganeso , Hierro/química , Hierro/metabolismo , Suelo/química , Biodegradación Ambiental , Microbiología del Suelo
3.
J Environ Sci (China) ; 147: 62-73, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003077

RESUMEN

Non-ferrous metal smelting poses significant risks to public health. Specifically, the copper smelting process releases arsenic, a semi-volatile metalloid, which poses an emerging exposure risk to both workers and nearby residents. To comprehensively understand the internal exposure risks of metal(loid)s from copper smelting, we explored eighteen metal(loid)s and arsenic metabolites in the urine of both occupational and non-occupational populations using inductively coupled plasma mass spectrometry with high-performance liquid chromatography and compared their health risks. Results showed that zinc and copper (485.38 and 14.00 µg/L), and arsenic, lead, cadmium, vanadium, tin and antimony (46.80, 6.82, 2.17, 0.40, 0.44 and 0.23 µg/L, respectively) in workers (n=179) were significantly higher compared to controls (n=168), while Zinc, tin and antimony (412.10, 0.51 and 0.15 µg/L, respectively) of residents were significantly higher than controls. Additionally, workers had a higher monomethyl arsenic percentage (MMA%), showing lower arsenic methylation capacity. Source appointment analysis identified arsenic, lead, cadmium, antimony, tin and thallium as co-exposure metal(loid)s from copper smelting, positively relating to the age of workers. The hazard index (HI) of workers exceeded 1.0, while residents and control were approximately at 1.0. Besides, all three populations had accumulated cancer risks exceeding 1.0 × 10-4, and arsenite (AsIII) was the main contributor to the variation of workers and residents. Furthermore, residents living closer to the smelting plant had higher health risks. This study reveals arsenic exposure metabolites and multiple metals as emerging contaminants for copper smelting exposure populations, providing valuable insights for pollution control in non-ferrous metal smelting.


Asunto(s)
Metalurgia , Exposición Profesional , Humanos , Exposición Profesional/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Metales/orina , Metales/análisis , Medición de Riesgo , Arsénico/análisis , Monitoreo del Ambiente , Adulto , Contaminantes Ambientales/análisis , Persona de Mediana Edad
4.
J Environ Sci (China) ; 148: 174-187, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095155

RESUMEN

Cost-effective CO2 adsorbents are gaining increasing attention as viable solutions for mitigating climate change. In this study, composites were synthesized by electrochemically combining the post-gasification residue of Macadamia nut shell with copper benzene-1,3,5-tricarboxylate (CuBTC). Among the different composites synthesized, the ratio of 1:1 between biochar and CuBTC (B 1:1) demonstrated the highest CO2 adsorption capacity. Under controlled laboratory conditions (0°C, 1 bar, without the influence of ambient moisture or CO2 diffusion limitations), B 1:1 achieved a CO2 adsorption capacity of 9.8 mmol/g, while under industrial-like conditions (25°C, 1 bar, taking into account the impact of ambient moisture and CO2 diffusion limitations within a bed of adsorbent), it reached 6.2 mmol/g. These values surpassed those reported for various advanced CO2 adsorbents investigated in previous studies. The superior performance of the B 1:1 composite can be attributed to the optimization of the number of active sites, porosity, and the preservation of the full physical and chemical surface properties of both parent materials. Furthermore, the composite exhibited a notable CO2/N2 selectivity and improved stability under moisture conditions. These favorable characteristics make B 1:1 a promising candidate for industrial applications.


Asunto(s)
Dióxido de Carbono , Estructuras Metalorgánicas , Dióxido de Carbono/química , Adsorción , Estructuras Metalorgánicas/química , Contaminantes Atmosféricos/química , Carbón Orgánico/química
5.
J Environ Sci (China) ; 148: 298-305, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095166

RESUMEN

Ultrasonic humidifiers are commonly used in households to maintain indoor humidity and generate a large number of droplets or spray aerosols. However, there have been various health concerns associated with humidifier use, largely due to aerosols generated during operation. Here, we investigated the size distribution, chemical composition, and charged fraction of aerosol particles emitted from commercial ultrasonic humidifiers. Heavy metals in water used for humidifiers were found to be highly enriched in the ultrasonic humidifier aerosols (UHA), with the enrichment factors ranging from 102 to 107. This enrichment may pose health concerns for the building occupants, as UHA concentrations of up to 106 particles/cm3 or 3 mg/m3 were observed. Furthermore, approximately 90% of UHA were observed to be electrically charged, for the first time according to our knowledge. Based on this discovery, we proposed and tested a new method to remove UHA by using a simple electrical field. The designed electrical field in this work can efficiently remove 81.4% of UHA. Therefore, applying this electrical field could be an effective method to significantly reduce the health risks by UHA.


Asunto(s)
Aerosoles , Humidificadores , Metales Pesados , Aerosoles/análisis , Metales Pesados/análisis , Contaminación del Aire Interior/prevención & control , Contaminación del Aire Interior/análisis , Contaminantes Atmosféricos/análisis , Ultrasonido , Monitoreo del Ambiente/métodos
6.
J Environ Sci (China) ; 148: 364-374, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095171

RESUMEN

Increasing nitrogen and phosphorus discharge and decreasing sediment input have made silicon (Si) a limiting element for diatoms in estuaries. Disturbances in nutrient structure and salinity fluctuation can greatly affect metal uptake by estuarine diatoms. However, the combined effects of Si and salinity on metal accumulation in these diatoms have not been evaluated. In this study, we aimed to investigate how salinity and Si availability combine to influence the adsorption of metals by a widely distributed diatom Phaeodactylum tricornutum. Our data indicate that replete Si and low salinity in seawater can enhance cadmium and copper adsorption onto the diatom surface. At the single-cell level, surface potential was a dominant factor determining metal adsorption, while surface roughness also contributed to the higher metal loading capacity at lower salinities. Using a combination of non-invasive micro-test technology, atomic force microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy, we demonstrate that the diversity and abundance of the functional groups embedded in diatom cell walls vary with salinity and Si supply. This results in a change in the cell surface potential and transient metal influx. Our study provides novel mechanisms to explain the highly variable metal adsorption capacity of a model estuarine diatom.


Asunto(s)
Diatomeas , Salinidad , Silicio , Contaminantes Químicos del Agua , Adsorción , Silicio/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Estuarios , Agua de Mar/química , Metales/química
7.
J Environ Sci (China) ; 148: 420-436, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095177

RESUMEN

Mercury (Hg) pollution has been a global concern in recent decades, posing a significant threat to entire ecosystems and human health due to its cumulative toxicity, persistence, and transport in the atmosphere. The intense interaction between mercury and selenium has opened up a new field for studying mercury removal from industrial flue gas pollutants. Besides the advantages of good Hg° capture performance and low secondary pollution of the mineral selenium compounds, the most noteworthy is the relatively low regeneration temperature, allowing adsorbent regeneration with low energy consumption, thus reducing the utilization cost and enabling recovery of mercury resources. This paper reviews the recent progress of mineral selenium compounds in flue gas mercury removal, introduces in detail the different types of mineral selenium compounds studied in the field of mercury removal, reviews the adsorption performance of various mineral selenium compounds adsorbents on mercury and the influence of flue gas components, such as reaction temperature, air velocity, and other factors, and summarizes the adsorption mechanism of different fugitive forms of selenium species. Based on the current research progress, future studies should focus on the economic performance and the performance of different carriers and sizes of adsorbents for the removal of Hg0 and the correlation between the gas-particle flow characteristics and gas phase mass transfer with the performance of Hg0 removal in practical industrial applications. In addition, it remains a challenge to distinguish the oxidation and adsorption of Hg0 quantitatively.


Asunto(s)
Contaminantes Atmosféricos , Mercurio , Mercurio/química , Adsorción , Contaminantes Atmosféricos/química , Selenio/química , Gases/química , Compuestos de Selenio/química
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124962, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39146628

RESUMEN

Two isostructural, three-dimensional, interpenetrated amino-functionalized Metal-Organic Frameworks (Co-2AIN-MOF and Cd-2AIN-MOF) based on 2-aminoisonicotinic acid (2AIN) were synthesized, structurally characterized and determined. Based on the PXRD analysis, the solvent exchange hardly changed their framework structure, and the samples fully activated by methanol can be achieved and examined by infrared spectroscopy. Due to the presence of the carbonyl group and free amino groups in the pore of the framework, the NH3 uptakes of Co-2AIN-MOF and Cd-2AIN-MOF are 11.70 and 13.81 mmol/g and at 1 bar, respectively. In-situ Infrared spectroscopy and DFT calculations revealed the different adsorption sites and processes between Co-2AIN-MOF and Cd-2AIN-MOF.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124989, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39154403

RESUMEN

A newly developed 2H5MA-MOF sensor by covalently linking NH2-MIL-53(Al) with 2'-Hydroxy-5'-methylacetophenon, designed for highly sensitive and selective detection of Cd2+ ions using fluorometric methods. Detailed structural and morphological analyses confirmed the sensor's unique properties. It demonstrated an impressive linear detection range from 0 to 2 ppm, with an exceptionally low detection limit of 5.77 × 10-2 ppm and a quantification limit of 1.75 × 10-1 ppm, indicating its high sensitivity (R2 = 0.9996). The sensor also responded quickly, detecting Cd2+ within just 30 s at pH 4. We successfully tested it on real samples of tap water and human blood plasma, achieving recovery rates between 96 % and 104 %. The accuracy of these findings was further validated by comparison with ICP-OES. Overall, the 2H5MA-MOF sensor shows great potential for fast, ultra-sensitive, and reliable detection of Cd2+ ions, making it a promising tool for environmental and biomedical applications.


Asunto(s)
Cadmio , Agua Potable , Límite de Detección , Estructuras Metalorgánicas , Cadmio/sangre , Cadmio/análisis , Humanos , Estructuras Metalorgánicas/química , Agua Potable/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/sangre , Iones/sangre , Concentración de Iones de Hidrógeno
10.
Artículo en Inglés | MEDLINE | ID: mdl-39323619

RESUMEN

Objectives: The multi-hole self-expandable metal stent (MHSEMS) is a novel SEMS with multiple small side holes on the covering membrane to prevent stent migration while minimizing tumor ingrowth. This study aimed to evaluate the clinical outcomes of MHSEMS in comparison with conventional covered SEMS (c-CMS). Methods: Consecutive patients with unresectable pancreatic cancer who underwent initial SEMS placement (MHSEMS or c-CMS) for malignant distal biliary obstruction were analyzed. Technical success, clinical success, causes of recurrent biliary obstruction (RBO), non-RBO adverse events, time to RBO (TRBO), and endoscopic reintervention were compared between groups. Results: A total of 65 patients were included (MHSEMS: 27, c-CMS: 38). The technical success, clinical success, and non-RBO adverse event rates were similar between groups. Although stent migration was less frequently observed in the MHSEMS group (0% vs. 17.6%, p = 0.032), overall RBO rates were similar between groups (53.8% vs. 55.9%, p > 0.99). The most common cause of RBO within 14 days in the MHSEMS group was non-occlusion cholangitis. Median TRBO was significantly shorter in the MHSEMS group (101 vs. 227 days, p = 0.030) and MHSEMS was an independent predictor for shorter TRBO in multivariate analysis (hazard ratio, 2.27; 95% confidence interval, 1.06-4.86; p = 0.034). Outcomes after endoscopic interventio were not significantly different between groups. Stent removal was successful in all attempted cases in both groups. Conclusions: MHSEMS was associated with a significantly shorter TRBO compared to c-CMS. Further modifications of the present MHSEMS may be needed.

11.
Biomaterials ; 312: 122755, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39151270

RESUMEN

Copper-catalyzed click chemistry offers creative strategies for activation of therapeutics without disrupting biological processes. Despite tremendous efforts, current copper catalysts face fundamental challenges in achieving high efficiency, atom economy, and tissue-specific selectivity. Herein, we develop a facile "mix-and-match synthetic strategy" to fabricate a biomimetic single-site copper-bipyridine-based cerium metal-organic framework (Cu/Ce-MOF@M) for efficient and tumor cell-specific bioorthogonal catalysis. This elegant methodology achieves isolated single-Cu-site within the MOF architecture, resulting in exceptionally high catalytic performance. Cu/Ce-MOF@M favors a 32.1-fold higher catalytic activity than the widely used MOF-supported copper nanoparticles at single-particle level, as first evidenced by single-molecule fluorescence microscopy. Furthermore, with cancer cell-membrane camouflage, Cu/Ce-MOF@M demonstrates preferential tropism for its parent cells. Simultaneously, the single-site CuII species within Cu/Ce-MOF@M are reduced by upregulated glutathione in cancerous cells to CuI for catalyzing the click reaction, enabling homotypic cancer cell-activated in situ drug synthesis. Additionally, Cu/Ce-MOF@M exhibits oxidase and peroxidase mimicking activities, further enhancing catalytic cancer therapy. This study guides the reasonable design of highly active heterogeneous transition-metal catalysts for targeted bioorthogonal reactions.


Asunto(s)
Materiales Biomiméticos , Cobre , Humanos , Cobre/química , Materiales Biomiméticos/química , Catálisis , Estructuras Metalorgánicas/química , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Cerio/química , Línea Celular Tumoral , Animales , Química Clic/métodos , Biomimética/métodos , Ratones
12.
J Environ Sci (China) ; 149: 374-385, 2025 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39181650

RESUMEN

Electrocatalytic reduction of nitrate to ammonia has been considered a promising and sustainable pathway for pollutant treatment and ammonia has significant potential as a clean energy. Therefore, the method has received much attention. In this work, Cu/Fe 2D bimetallic metal-organic frameworks were synthesized by a facile method applied as cathode materials without high-temperature carbonization. Bimetallic centers (Cu, Fe) with enhanced intrinsic activity demonstrated higher removal efficiency. Meanwhile, the 2D nanosheet reduced the mass transfer barrier between the catalyst and nitrate and increased the reaction kinetics. Therefore, the catalysts with a 2D structure showed much better removal efficiency than other structures (3D MOFs and Bulk MOFs). Under optimal conditions, Cu/Fe-2D MOF exhibited high nitrate removal efficiency (87.8%) and ammonium selectivity (89.3%) simultaneously. The ammonium yielded up to significantly 907.2 µg/(hr·mgcat) (7793.8 µg/(hr·mgmetal)) with Faradaic efficiency of 62.8% at an initial 100 mg N/L. The catalyst was proved to have good stability and was recycled 15 times with excellent effect. DFT simulations confirm the reduced Gibbs free energy of Cu/Fe-2D MOF. This study demonstrates the promising application of Cu/Fe-2D MOF in nitrate reduction to ammonia and provides new insights for the design of efficient electrode materials.


Asunto(s)
Amoníaco , Cobre , Hierro , Estructuras Metalorgánicas , Nitratos , Contaminantes Químicos del Agua , Amoníaco/química , Cobre/química , Nitratos/química , Estructuras Metalorgánicas/química , Hierro/química , Contaminantes Químicos del Agua/química , Catálisis , Modelos Químicos , Oxidación-Reducción , Cinética
13.
J Environ Sci (China) ; 149: 598-615, 2025 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39181671

RESUMEN

Catalytic hydrogenation of CO2 to ethanol is a promising solution to address the greenhouse gas (GHG) emissions, but many current catalysts face efficiency and cost challenges. Cobalt based catalysts are frequently examined due to their abundance, cost-efficiency, and effectiveness in the reaction, where managing the Co0 to Coδ+ ratio is essential. In this study, we adjusted support nature (Al2O3, MgO-MgAl2O4, and MgO) and reduction conditions to optimize this balance of Co0 to Coδ+ sites on the catalyst surface, enhancing ethanol production. The selectivity of ethanol reached 17.9% in a continuous flow fixed bed micro-reactor over 20 mol% Co@MgO-MgAl2O4 (CoMgAl) catalyst at 270 °C and 3.0 MPa, when reduced at 400 °C for 8 h. Characterisation results coupled with activity analysis confirmed that mild reduction condition (400 °C, 10% H2 balance N2, 8 h) with intermediate metal support interaction favoured the generation of partially reduced Co sites (Coδ+ and Co0 sites in single atom) over MgO-MgAl2O4 surface, which promoted ethanol synthesis by coupling of dissociative (CHx*)/non-dissociative (CHxO*) intermediates, as confirmed by density functional theory analysis. Additionally, the CoMgAl, affordably prepared through the coprecipitation method, offers a potential alternative for CO2 hydrogenation to yield valuable chemicals.


Asunto(s)
Dióxido de Carbono , Cobalto , Etanol , Dióxido de Carbono/química , Etanol/química , Hidrogenación , Cobalto/química , Catálisis , Nanopartículas/química , Modelos Químicos
14.
J Environ Sci (China) ; 149: 688-698, 2025 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39181679

RESUMEN

Coking industry is a potential source of heavy metals (HMs) pollution. However, its impacts to the groundwater of surrounding residential areas have not been well understood. This study investigated the pollution characteristics and health risks of HMs in groundwater nearby a typical coking plant. Nine HMs including Fe, Zn, Mo, As, Cu, Ni, Cr, Pb and Cd were analyzed. The average concentration of total HMs was higher in the nearby area (244.27 µg/L) than that of remote area away the coking plant (89.15 µg/L). The spatial distribution of pollution indices including heavy metal pollution index (HPI), Nemerow index (NI) and contamination degree (CD), all demonstrated higher values at the nearby residential areas, suggesting coking activity could significantly impact the HMs distribution characteristics. Four sources of HMs were identified by Positive Matrix Factorization (PMF) model, which indicated coal washing and coking emission were the dominant sources, accounted for 40.4%, and 31.0%, respectively. Oral ingestion was found to be the dominant exposure pathway with higher exposure dose to children than adults. Hazard quotient (HQ) values were below 1.0, suggesting negligible non-carcinogenic health risks, while potential carcinogenic risks were from Pb and Ni with cancer risk (CR) values > 10-6. Monte Carlo simulation matched well with the calculated results with HMs concentrations to be the most sensitive parameters. This study provides insights into understanding how the industrial coking activities can impact the HMs pollution characteristics in groundwater, thus facilitating the implement of HMs regulation in coking industries.


Asunto(s)
Coque , Monitoreo del Ambiente , Agua Subterránea , Metales Pesados , Contaminantes Químicos del Agua , Metales Pesados/análisis , Agua Subterránea/química , Agua Subterránea/análisis , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , Humanos
15.
Artículo en Inglés | MEDLINE | ID: mdl-39228862

RESUMEN

Background: Stent migration and sludge formation remain significant problems associated with covered self-expandable metal stents (CSEMSs). The EGIS biliary stent fully covered flare type (EGIS biliary stent), a new type of polytetrafluoroethylene-coated self-expandable metal stent with low axial force and an anti-migration system, was developed to overcome these disadvantages. We conducted this study to evaluate the efficacy and safety of this stent in comparison with conventional CSEMS (c-CSEMS). Methods: We retrospectively analyzed consecutive patients with unresectable pancreatic cancer who received initial CSEMS for distal malignant biliary obstruction. The primary outcome was time to recurrent biliary obstruction (RBO). Secondary outcomes included technical success rate, functional success rate, stent-related adverse events, causes of RBO, and re-intervention. Results: A total of 40 patients were included (EGIS group: 20; c-CSEMS group: 20). The technical and functional success rates were similar between the two groups. Stent-related adverse event rates (20% vs. 15%, p > 0.99) and overall RBO rates (56% vs. 50%, p > 0.99) were not significantly different between the two groups. Stent migration was the most common cause of RBO in the EGIS group, while stent occlusion was in the c-CSEMS group. The median time to RBO (102 vs. 434 days, p = 0.10) was not significantly different between the two groups. Endoscopic transpapillary re-intervention was successful in most patients in both groups. Conclusions: The EGIS biliary stent was not associated with a longer time to RBO compared to c-CSEMS. Further improvements, especially against stent migration, are needed to improve its efficacy.

16.
Food Chem ; 462: 140962, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39241683

RESUMEN

Nitrite is a common ingredient in the industry and agriculture; it is everywhere, like water, food, and surroundings. Recently, several approaches have been developed to measure the nitrite levels. So, this review was presented as a summary of many approaches utilized to detect the nitrite. Furthermore, the types of information that may be acquired using these methodologies, including optic and electrical signals, were discussed. In electrical signal methods, electrochemical sensors are usually developed using different materials, including carbon, polymers, oxides, and hydroxides. At the same time, optic signals receiving techniques involve utilizing fluorescence chromatography, absorption, and spectrometry instruments. Furthermore, these methodologies' benefits, drawbacks, and restrictions are examined. Lastly, due to the efficiency and fast means of electrochemical detectors, it was suggested that they can be used for detecting nitrite in food safety. Futuristic advancements in the techniques used for nitrite determination are subsequently outlined.


Asunto(s)
Técnicas Electroquímicas , Análisis de los Alimentos , Contaminación de Alimentos , Nitritos , Nitritos/análisis , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Contaminación de Alimentos/análisis , Análisis de los Alimentos/métodos , Análisis de los Alimentos/instrumentación
17.
J Environ Sci (China) ; 150: 149-158, 2025 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39306392

RESUMEN

Acid-base dissociable antibiotic-metal complexes are known to be emerging contaminants in the aquatic environments. However, little information is available on the photochemical properties and toxicity of these complex forms. This study investigated the spectral properties of three fluoroquinolones (FQs) with and without metal ions Fe(III), Cu(II), and Al(III) in solutions under different pH conditions, as well as evaluated the changes in toxicity due to the complex with these metal ions using luminescent bacteria (vibrio fischeri). FQs showed a higher tendency to coordinate metal ions under alkaline conditions compared to neutral and acidic conditions, and the formation of complexes weakened the ultraviolet-absorbing ability of FQs. At pH = 7.0, Cu(II) quenched the fluorescence intensity of FQs. Moreover, their Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy were explored, revealing that the coordination sites of Cu(II) in three FQs were situated in a bidentate manner through the oxygen atom of the deprotonated carboxyl group and cyclic carbonyl oxygen atom. This conclusion was further verified by the theory of molecular surface electrostatic potential. In addition, except for complexes of ciprofloxacin-metals, enhanced toxicity of FQs upon coordination with Fe(III) was observed, while reduced toxicity was found for coordination with Cu(II) and Al(III). These results are important for accurately evaluating the photochemical behavior and risk of these antibiotics in aquatic environments contaminated with metal ions.


Asunto(s)
Antibacterianos , Fluoroquinolonas , Contaminantes Químicos del Agua , Fluoroquinolonas/química , Fluoroquinolonas/toxicidad , Antibacterianos/química , Antibacterianos/toxicidad , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Metales/química , Metales/toxicidad , Aliivibrio fischeri/efectos de los fármacos , Procesos Fotoquímicos
18.
J Environ Sci (China) ; 150: 432-439, 2025 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39306418

RESUMEN

The floodplain of the Yellow River is a typical area characterized by redox fluctuations and heavy metal pollution. However, the mobilization behavior of heavy metals in floodplain sediments during redox fluctuations remains poorly understood. In this study, reductive mobilization of Fe and Mn was observed under reducing environments through reduction and dissolution, leading to the subsequent release of adsorbed As. In contrast, the mobilization of U occurred under oxic conditions, as the oxidative state of U(VI) has higher solubility. Furthermore, insignificant effects on the mobilization of Cd, Cu, Pb, and Hg were noticed during redox fluctuations, indicating higher stability of these heavy metals. Additionally, we demonstrated that carbon sources can play a key role in the mobilization of heavy metals in floodplain sediments, amplifying the reductive mobilization of Fe, Mn, As and the oxidative mobilization of U. Our findings contribute to the understanding of the biogeochemical cycling of heavy metal in floodplain sediments of the Yellow River and the factors that control this cycling.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados , Oxidación-Reducción , Ríos , Contaminantes Químicos del Agua , Metales Pesados/análisis , Ríos/química , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , China
19.
J Environ Sci (China) ; 150: 582-593, 2025 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39306431

RESUMEN

Coal power plants annually generate quantities of byproducts that release environmentally hazardous heavy metals like Cd and Pb. Understanding the behavior and spatiotemporal impacts on soils of these releases is crucial for pollution control. This study investigated the concentrations and isotope ratios of Cd/Pb in combustion byproducts, depositions and soils collected from a coal-fired power plant or its surrounding area. The pulverized fuel ash (PFA) and desulfurized gypsum (DG) exhibited heavier Cd isotopes with Δ114Cd values of 0.304‰ and 0.269‰, respectively, while bottom ash (BA) showed lighter Cd isotopes (Δ114CdBA-coal = -0.078‰), compared to feed coal. We proposed a two-stage condensation process that governs the distribution of Cd/Pb, including accumulation on PFA and DG within electrostatic precipitators and desulfurization unit, as well as condensation onto fine particles upon release from the stack. Emissions from combustion and large-scale transport make a significant contribution to deposition, while the dispersion of Cd/Pb in deposition is primarily influenced by the prevailing wind patterns. However, the distribution of Cd/Pb in soils not only exhibit predominant wind control but is also potentially influenced by the resuspension of long-term storage byproducts. The power plant significantly contributes to soil in the NW-N-NE directions, even at a considerable distance (66%-79%), demonstrating its pervasive impact on remote regions along these orientations. Additionally, based on the vertical behavior in the profile, we have identified that Cd tends to migrate downward through leaching, while variations in Pb respond to the historical progression of dust removal.


Asunto(s)
Cadmio , Carbón Mineral , Monitoreo del Ambiente , Centrales Eléctricas , Contaminantes del Suelo , Suelo , Cadmio/análisis , Contaminantes del Suelo/análisis , Suelo/química , Plomo/análisis
20.
Nano Lett ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365276

RESUMEN

Atomically precise Pd-thiolate clusters are well-known for their well-defined structures and diverse applications involving catalysis, sensors, and biomedicine. While many of these clusters have been studied, their molecular structures typically feature a tiara-like arrangement. In this study, we present the first example of a non-tiara-like Pd-thiolate cluster: the octahedral Pd6(SC6H11)12 (denoted as Pd6-Oct). The composition and geometric structure of the cluster were characterized using electrospray ionization mass spectrometry (ESI-MS) together with single-crystal X-ray diffraction (SXRD). Despite having a similar chemical composition to tiara-like Pd6(SC2H4Ph)12 (denoted as Pd6-Tia), Pd6-Oct exhibits a distinctly different geometric structure. Additionally, UV-vis-NIR absorption spectroscopy combined with quantum chemical calculations provided valuable insights into the electronic structures of these clusters. The excited-state dynamics, host-guest chemistry, and the catalytic properties of Pd6-Oct and Pd6-Tia were examined to compare their structure-property relationships. This research represents significant advances in the synthesis and understanding of structure-property correlations in Pd-thiolate clusters.

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