Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.200
Filtrar
1.
J Colloid Interface Sci ; 677(Pt B): 417-428, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39153245

RESUMEN

Synthesis of catalysts with high catalytic degradation activity for formaldehyde (HCHO) at room temperature is highly desirable for indoor air quality control. Herein, a novel K-Mn3O4@CeO2 catalyst with excellent catalytic oxidation activity toward HCHO at near room temperature was reported. In particular, the K addition in K-Mn3O4@CeO2 considerably enhanced the oxidation activity, and importantly, 99.3 % conversion of 10 mL of a 40 mg/L HCHO solution at 30 °C for 14 h was achieved, with simultaneous strong cycling stability. Moreover, the addition of K species considerably influenced the chemical valence state of Mn from +4 (ε-MnO2) to +8/3 (Mn3O4) on the surface of CeO2, which obviously changed the tunnel structure and the number of oxygen vacancies. One part of K species is uniformly dispersed on K-Mn3O4@CeO2, and the other part exists in the tunnel structure of Mn3O4@CeO2, which is mainly used to balance the negative charge of the tunnel and prevent collapse of the structure, providing enough active sites for the catalytic oxidation of HCHO. We observed a phase transition from tunneled KMnO2 to Mn3O4 to tunneled MnO2 with the decreasing K+ content, in which K-Mn3O4@CeO2 exhibited higher HCHO oxidation activity. In addition, K-Mn3O4@CeO2 exhibited lower oxygen vacancy formation and HCHO adsorption energies in aqueous solution based on density functional theory calculations. This is because the K species provide more active oxygen species and richer oxygen vacancies on the surface of K-Mn3O4@CeO2, promote the mobility of lattice oxygen and the room-temperature reduction properties of oxygen species, and enhance the ability of the catalyst to replenish the consumed oxygen species. Finally, a possible HCHO catalytic oxidation pathway on the surface of K-Mn3O4@CeO2 catalyst is proposed.

2.
Sci Bull (Beijing) ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39366829

RESUMEN

Elevated concentrations of formaldehyde and other carbonyl compounds are frequently observed in the marine atmosphere but are often significantly underestimated by atmospheric models. To evaluate the potential impact of marine sources on atmospheric formaldehyde, high-resolution measurements were conducted at a coastal site (∼15 m from the sea) during the summer in Qingdao, China. Observed formaldehyde levels averaged 2.4 ± 0.9 ppbv (1 ppbv = 10-9 L L-1), with peaks reaching 6.8 ppbv. Backward trajectories indicate that formaldehyde concentrations remained high in marine air masses. Formaldehyde exhibited weak correlations with primary pollutants such as NO and CO but showed strong correlations with marine tracers, notably methyl ethyl ketone and 1-butene. Chamber experiments confirmed that the photodecomposition of Enteromorpha released large amounts of formaldehyde and marine tracer species. When normalized to acetylene, the levels of formaldehyde, 1-butene, and MEK increased by factors of 3.8, 8.1, and 3.5, respectively. Results from an observation-based chemical box model simulation, which utilizes the Master Chemical Mechanism (MCM), revealed that formaldehyde contributes 56% to the primary source of HO2 radicals, while neglecting formaldehyde chemistry would lead to a 15% reduction in coastal ozone production rates. This study interlinks oceanic biology and atmospheric chemistry, advancing the understanding of the ocean's role as a significant source of organic compounds and its contribution to carbon cycling.

3.
Food Chem ; 463(Pt 4): 141463, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39362098

RESUMEN

To characterize the interaction between banana condensed tannins (BCT) and formaldehyde as well as elucidate the involving mechanism, different techniques were utilized in the present study. Our results showed that BCT were a mixture of procyanidins and prodelphinidins with the degree of the polymerization of 2-9. With the increasing condensed tannin concentration (0.125-0.625 mg CE/mL), the formaldehyde scavenging ability of BCT (32.16-78.64 %) continuously enhanced. It was shown that formaldehyde could quench the fluorescence of BCT through a dynamic mechanism, while the binding of BCT and formaldehyde was a spontaneous process. According to the data of scavenging ability and spectroscopic analyse, the hydrophobic and covalent interactions between BCT and formaldehyde mainly contributed to the formaldehyde scavenging ability of BCT Moreover, the morphologies of BCT-formaldehyde complexes confirmed the interactions between BCT and formaldehyde as well. Therefore, BCT could be developed as promising formaldehyde scavengers during food production and processing in the future.

4.
J Pharm Pharmacol ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39374956

RESUMEN

OBJECTIVE: Farnesol (FAR), a sesquiterpene alcohol, has documented FAR's anti-inflammatory and antioxidant activities. Current study was undertaken to assess the efficacy and mechanism of FAR in arthritis by employing network pharmacology and experimental models. METHODS: Two experimental models comprising formaldehyde- and complete Freund's adjuvant (CFA)-induced arthritis evaluated the efficacy of FAR in treating arthritis. Various parameters were assessed. Then, a network pharmacology approach was applied to gain further insight into the potential mechanism and signaling pathways. KEY FINDINGS: FAR significantly reduced paw volume and the arthritic score and improved the hematological and biochemical changes. Radiographic and histological examination showed the anti-arthritic efficacy of FAR, which was associated with down-regulation of pro-inflammatory mediators and upregulation of anti-inflammatory mediators. Network pharmacology analysis revealed that FAR may exert its anti-arthritic effects by targeting specific genes associated with arthritis. Pathway analysis revealed the involvement of three key signaling pathways (IL-17 signaling, TNF signaling, and toll-like receptor signaling) in the development and progression of arthritis. CONCLUSIONS: The results pointed out the protective attributes of farnesol against formaldehyde and CFA-induced arthritis via modulation of multiple targets. This study provides a valuable reference for the development of a new treatment or complementary therapy for arthritis.

5.
Cell Biol Toxicol ; 40(1): 83, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367211

RESUMEN

Exogenous gaseous formaldehyde (FA) is recognized as a significant indoor air pollutant due to its chemical reactivity and documented mutagenic and carcinogenic properties, particularly in its capacity to damage DNA and impact human health. Despite increasing attention on the adverse effects of exogenous FA on human health, the potential detrimental effects of endogenous FA in the brain have been largely neglected in current research. Endogenous FA have been observed to accumulate in the aging brain due to dysregulation in the expression and activity of enzymes involved in FA metabolism. Surprisingly, excessive FA have been implicated in the development of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and brain cancers. Notably, FA has the ability to not only initiate DNA double strand breaks but also induce the formation of crosslinks of DNA-DNA, DNA-RNA, and DNA-protein, which further exacerbate the progression of these brain diseases. However, recent research has identified that FA-resistant gene exonuclease-1 (EXO1) and FA scavengers can potentially mitigate FA toxicity, offering a promising strategy for mitigating or repairing FA-induced DNA damage. The present review offers novel insights into the impact of FA metabolism on brain ageing and the contribution of FA-damaged DNA to the progression of neurological disorders.


Asunto(s)
Envejecimiento , Encéfalo , Daño del ADN , Formaldehído , Humanos , Formaldehído/toxicidad , Formaldehído/efectos adversos , Envejecimiento/metabolismo , Envejecimiento/genética , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/patología , Daño del ADN/efectos de los fármacos , Animales , Encefalopatías/inducido químicamente , Encefalopatías/metabolismo , Encefalopatías/patología , Encefalopatías/genética
6.
J Colloid Interface Sci ; 679(Pt A): 624-633, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39388949

RESUMEN

As a battery-type anode material for sodium ion capacitors (SICs), titanate (H2Ti2O5·H2O, HTO) exhibits good rate capability due to its layered structure, easy to insert Na+ ions and low potential during sodium-ion storage. However, the structure is unstable due to the lattice distortion resulting from the irreversible embedment of Na+ in the process of sodium storage. So there is a significant mismatch between the dynamic reaction of the HTO anode and the capacitive cathode. Surface coating engineering is a useful strategy for stabilizing the HTO structure, which is critical for improving the kinetic response. In this work, a surface coating technique is designed to enhance the surface of HTO nanoarrays on titanium foil by using the oligomers of tannic acid formaldehyde polymer (TAF) chelated Bi3+ ions (Bi-TAF). As a binder-free anode, HTO coated with Bi-TAF (HTO@Bi-TAF) exhibits more excellent capacity (335.2 mA h g-1, 0.1 A g-1), rate capability (212.3 mA h g-1, 2.0 A g-1), and cycle stability (97 % capacity maintenance following 2000 cycles at 1.0 A g-1) than HTO and HTO coated with TAF (HTO@TAF). At the sweep rate of 1.0 mV s-1, the kinetic investigation reveals that the capacitance contribution of HTO@Bi-TAF is 86 %. The SICs exhibit a significant energy/power density (89.4 Wh kg-1/250 W kg-1). This work shows that the Bi-TAF polymer coating has a dual effect of rate capability improvement and structural protection on the prepared HTO. This results in a reasonable and effective surface coating strategy that provides outstanding rate capability and extended cycle performance of titanium-based anode materials for SICs.

7.
Mol Med Rep ; 30(6)2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39392030

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disorder that impairs learning and memory, with high rates of mortality. Birch bark has been traditionally used in the treatment of various skin ailments. Betulin (BT) is a key compound of birch bark that exhibits diverse pharmacological benefits and therapeutic potential in AD. However, the therapeutic effects and molecular mechanisms of BT in AD remain unclear. The present study aimed to predict the potential therapeutic targets of BT in the treatment of AD, and to determine the specific underlying molecular mechanisms through network pharmacology analysis and experimental validation. PharmMapper was used to predict the target genes of BT, and four disease databases were searched to screen for AD targets. The intersection targets were identified using the jveen website. Drug­disease target protein­protein interaction networks and hub genes were obtained and visualized using the Search Tool for the Retrieval of Interacting Genes/Proteins database and Cytoscape. The Database for Annotation, Visualization and Integrated Discovery was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and AutoDock was used for molecular docking analysis of BT and hub genes. Subsequently, the network­predicted mechanisms of BT in AD were verified in vitro. A total of 495 BT and 1,386 AD targets were identified, and 120 were identified as potential targets of BT in the treatment of AD. The results of the molecular docking analysis revealed a strong binding affinity between BT and the hub genes. In addition, enrichment analyses of GO and KEGG pathways indicated that the neuroprotective effects of BT mainly involved the 'PI3K­Akt signaling pathway'. The results of in vitro experiments demonstrated that pretreatment with BT for 2 h may ameliorate formaldehyde (FA)­induced cytotoxicity and morphological changes in HT22 cells, and decrease FA­induced Tau hyperphosphorylation and reactive oxygen species levels. Furthermore, the PI3K/AKT signaling pathway was activated and the expression levels of downstream proteins, namely GSK3ß, Bcl­2 and Bax, were modified following pre­treatment with BT. Overall, the results of network pharmacology and in vitro analyses revealed that BT may reduce FA­induced AD­like pathology by modulating the PI3K/AKT signaling pathway, highlighting it as a potential multi­target drug for the treatment of AD.


Asunto(s)
Enfermedad de Alzheimer , Simulación del Acoplamiento Molecular , Farmacología en Red , Mapas de Interacción de Proteínas , Triterpenos , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Triterpenos/farmacología , Triterpenos/química , Humanos , Mapas de Interacción de Proteínas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/uso terapéutico , Redes Reguladoras de Genes/efectos de los fármacos , Ontología de Genes , Animales , Ácido Betulínico
8.
Heliyon ; 10(19): e38442, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39391498

RESUMEN

The most significant environmental issue in many nations across the world is industrial wastewater contamination with formaldehyde (a priority pollutant). Any natural water that has had industrial effluent discharged into with formaldehyde concentrations between 100 and 1000 mg/l is deemed toxic to humans. This is an applied analytical research project aimed at examining formaldehyde removal from urban drinking water using a batch electro-photocatalytic (EPC) reactor that uses ultraviolet-A (UV-A) lamp dynode and immobilized ZnO NPs on a zinc sheet-copper electrode. pH, formaldehyde content, lamp intensity, radiation duration, lamp-electrode distance, ZnO NP stacking, and current density are the factors under investigation. They were found to be in the ranges 3-11, 110-330 mg/l, 480-720 mW/cm2, 8-32 min, 1.5 cm, 1-3, and 4-12 mA/cm2, respectively. The findings demonstrate the relationship between UV-A lamp intensity, radiation duration, and current density with the elimination of formaldehyde. The experimental data better fit a first-order reaction (R2 = 0.9982). The most optimal conditions elimination (0 mg/l) of formaldehyde are achieved at pH = 11, radiation period = 8 min, two layers of ZnO NPs, and current density = 8 mA/cm2 by the Taguchi model. The results show that increasing pH, radiation period, lamp intensity, and current density all increase removal efficiency. The results show that EPC is a practical and efficient method for treating formaldehyde-contaminated drinking water at high concentrations.

9.
ACS Synth Biol ; 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39395007

RESUMEN

Formaldehyde is an intermediate metabolite of methylotrophic microorganisms that can be obtained from formate and methanol through oxidation-reduction reactions. Formaldehyde is also a one-carbon (C1) compound with high uniquely reactive activity and versatility, which is more amenable to further biocatalysis. Biosynthesis of high-value-added chemicals using formaldehyde as an intermediate is theoretically feasible and promising. This review focuses on the design of the biosynthesis of high-value-added chemicals using formaldehyde as an essential intermediate. The upstream biosynthesis and downstream bioconversion pathways of formaldehyde as an intermediate metabolite are described in detail, aiming to highlight the important role of formaldehyde in the transition from inorganic to organic carbon and carbon chain elongation. In addition, challenges and future directions of formaldehyde as an intermediate for the chemicals are discussed, with the expectation of providing ideas for the utilization of C1.

10.
Chemosphere ; : 143499, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39395479

RESUMEN

Formaldehyde (HCHO), a ubiquitous volatile organic compound and recognized human carcinogen, is extensively used in industrial applications such as resin and adhesive production. Even minimal exposure to HCHO can induce serious health effects, including respiratory distress and dermal irritation. Thus, the advancement of highly sensitive and selective sensors for HCHO detection is imperative for safeguarding environmental and indoor air quality. Herein, we report the development of a very sensitive, highly selective, and stable HCHO sensor based on reduced graphene oxide (rGO) and lanthanum ferrite (LaFeO3). LaFeO3 and rGO-LaFeO3 nanocomposites with different compositions were synthesized through an affordable and straightforward sol-gel process. Among them, the LFGO(50:1) sensor demonstrated the highest response and selectivity towards HCHO, with a detection limit (theoretically) as low as 19 ppb (1.5 fold). Notably, it exhibited approximately 15-fold p-type response to 1 ppm of HCHO, while operating at 260°C. The sensor also showed quick response and recovery times of around 1.5 seconds and 36 seconds, respectively while having negligible response to other VOCs, including ethanol, methanol, and NH3. A synergistic effect of rGO and LaFeO3 is attributed to this improved sensing behavior. rGO offers a large surface area that facilitates the adsorption of HCHO molecules, while LaFeO3 acts as a catalyst for the oxidation of HCHO. The sensor also showed good selectivity, stability, and reproducibility, making the material a promising candidate for practical applications towards environment monitoring, indoor air quality control, and industrial safety.

11.
Transl Anim Sci ; 8: txae121, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39219715

RESUMEN

Formaldehyde has been found to decrease virus concentrations in feed and ingredient matrices. Continued research is needed to identify the appropriate inclusion levels and application time for different viruses in these matrices. The objective was to evaluate different inclusion levels of formaldehyde when applied either pre- or postinoculation of porcine epidemic diarrhea virus (PEDV), type 2 porcine reproductive and respiratory syndrome virus (PRRSV), and Seneca Valley virus 1 (SVV1) to complete feed or soybean meal. The experiment was designed in a 2 × 2 factorial with a formaldehyde-based product (Termin-8, Anitox Corporation, Lawrenceville, GA) applied either before virus inoculation (preinoculation) or after inoculation (postinoculation) at either a 2 or 3 kg/MT. On day 0, samples of the respective matrices were weighed in 50 g aliquots and added to 500 mL bottles. Formaldehyde was applied to the preinoculation samples at the respective inclusion levels and 50 µL of each virus were added to the postinoculation samples. All bottles were shaken and allowed to sit at room temperature for 24 h. On day 1, virus was added to the preinoculation samples and formaldehyde was added to the postinoculation bottles. Half of the samples were immediately processed (0 h) and the other half were incubated at room temperature for an additional 24 h. Samples were processed and aliquots were analyzed via triplex PCR. An application time × inclusion level interaction was observed for PEDV at 0 h and SVV1 and PEDV at 24 h in complete feed, where less viral RNA (P < 0.05) was detected in the postinoculation samples at either inclusion level as compared to the positive controls. In soybean meal, the same interaction was observed in PEDV and PRRSV at 0 h and SVV1 and PEDV at 24 h with less detectable RNA observed (P < 0.05) in the postinoculation samples regardless of inclusion level than the preinoculation counterparts and the controls. Overall, an application time effect was noticed in each matrix where less RNA was detected in the postinoculation samples at 0 h (P < 0.05) compared to the preinoculation samples and the control, and at 24 h, both the pre- and postinoculation samples had less detectable RNA (P < 0.05) than the control. Overall, formaldehyde can reduce detectable RNA immediately in contaminated complete feed and soybean meal, with greater decreases observed as mitigant contact time increases.

13.
Polymers (Basel) ; 16(17)2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39274043

RESUMEN

Dental resin composites are widely used in clinical settings but often face longevity issues due to the development and accumulation of microcracks, which eventually lead to larger cracks and restoration failure. The incorporation of microcapsules into these resins has been explored to introduce self-healing capability, potentially extending the lifespan of the restorations. This study aims to enhance the performance of self-healing dental resins by optimizing the microcapsules-resin matrix physicochemical interactions. Poly(urea-formaldehyde) (PUF) microcapsules were reinforced with melamine and subsequently subjected to surface functionalization with 3-aminopropyltriethoxysilane (APTES) and (3-mercaptopropyl)trimethoxysilane (MPTMS). Additionally, microcapsules were functionalized with a bilayer approach, incorporating tetraethyl orthosilicate (TEOS) with either APTES or MPTMS. X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) confirmed an increased Si:C ratio from 0.006 to 0.165. The functionalization process did not adversely affect the structure of the microcapsules or their healing agent volume. Compared to PUF controls, the functionalized microcapsules demonstrated enhanced healing efficiency, with TEOS/MPTMS-functionalized microcapsules showing the highest performance, showing a toughness recovery of up to 35%. This work introduces a novel approach to functionalization of microcapsules by employing advanced silanizing agents such as APTES and MPTMS, and pioneering bilayer functionalization protocols through their combination with TEOS.

14.
Polymers (Basel) ; 16(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39274095

RESUMEN

This paper presents a two-stage microencapsulation process that uses pH modulation to enhance the thermal stability of microcapsules that consist of a melamine-formaldehyde (MF) shell and a butyl stearate core. In the first stage, the pH value was modulated between 6.0 and 8.0. Rising the pH value to 8.0 slowed the polycondensation rate, allowing the MF resin with a lower degree of polymerization to migrate to the capsule surface and form a smooth shell. Lowering the pH value to 6.0 accelerated polycondensation. In the second stage, a relatively fast, continuous reduction in the pH value to 5.0 led to further MF polycondensation, hardening the shell. Post-curing at 100 °C prevented shell damage caused by the liquid-gas phase transition of the core material during the process. The microcapsules produced by increasing the pH value to 8.0 twice demonstrated improved thermal stability, with only a minimal overall weight loss of 5% at 300 °C. Significant weight loss was observed between 350 and 400 °C, temperatures at which the methylene bridges in the MF shell undergo thermal degradation. The results from differential scanning calorimetry, electron microscopy, and thermogravimetry analyses confirmed a successful optimization of the microencapsulation, showing that these microcapsules are promising for thermal energy storage and other applications that require high thermal stability.

15.
Molecules ; 29(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39274907

RESUMEN

Catalytic performance decline is a general issue when shaping fine powder into macroscale catalysts (e.g., beads, fiber, pellets). To address this challenge, a phenolic resin-assisted strategy was proposed to prepare porous Co/N carbon beads (ZACBs) at millimeter scale via the phase inversion method followed by confined pyrolysis. Specially, p-aminophenol-formaldehyde (AF) resin-coated zeolitic imidazolate framework (ZIF-67) nanoparticles were introduced to polyacrylonitrile (PAN) solution before pyrolysis. The thermosetting of the coated AF improved the interface compatibility between the ZIF-67 and PAN matrix, inhibiting the shrinkage of ZIF-67 particles, thus significantly improving the void structure of ZIF-67 and the dispersion of active species. The obtained ZACBs exhibited a 99.9% removal rate of tetracycline (TC) within 120 min, with a rate constant of 0.069 min-1 (2.3 times of ZIF-67/PAN carbon beads). The quenching experiments and electron paramagnetic resonance (EPR) tests showed that radicals dominated the reaction. This work provides new insight into the fabrication of high-performance MOF catalysts with outstanding recycling properties, which may promote the use of MOF powder in more practical applications.

16.
DNA Repair (Amst) ; 142: 103754, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39232366

RESUMEN

Transcription reprogramming is essential to carry out a variety of cell dynamics such as differentiation and stress response. During reprogramming of transcription, a number of adverse effects occur and potentially compromise genomic stability. Formaldehyde as an obligatory byproduct is generated in the nucleus via oxidative protein demethylation at regulatory regions, leading to the formation of DNA crosslinking damage. Elevated levels of transcription activities can result in the accumulation of unscheduled R-loop. DNA strand breaks can form if processed 5-methylcytosines are exercised by DNA glycosylase during imprint reversal. When cellular differentiation involves a large number of genes undergoing transcription reprogramming, these endogenous DNA lesions and damage-prone structures may pose a significant threat to genome stability. In this review, we discuss how DNA damage is formed during cellular differentiation, cellular mechanisms for their removal, and diseases associated with transcription reprogramming.


Asunto(s)
Reprogramación Celular , Daño del ADN , Transcripción Genética , Humanos , Animales , Reparación del ADN , Diferenciación Celular , Inestabilidad Genómica
17.
J Environ Manage ; 370: 122434, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39265492

RESUMEN

Photothermal catalytic oxidation is a promising and sustainable method for the degradation of indoor formaldehyde (HCHO). However, the excessively high surface temperature of existing photothermal catalysts during catalysis hinders the effective adsorption and degradation of formaldehyde under static conditions. Catalyst loading and oxygen vacancies (OVs) modulation are commonly employed strategies to reduce the photothermal catalytic temperature and enhance the efficiency of photothermal catalytic oxidation. In this work, a p-n type CuO/TiO2 heterojunction is successfully loaded onto diatomite using a wet precipitation method. Under the irradiation of a 300W xenon lamp, the prepared composite material achieved a 100% removal rate of HCHO within 2 h, with a 98% conversion rate to CO2, surpassing the performance of both individual photocatalysts and thermocatalysts. Additionally, by adjusting conditions such as light irradiation and temperature, we have demonstrated that this material exhibits synergistic photothermal catalytic properties. Based on HRTEM, XPS, Raman, and EPR analyses, the introduction of diatomite as a catalyst support was shown to effectively increase the number of OVs. Experimental results, along with O2-TPD, photoelectrochemical characterization, and radical detection, demonstrate that the presence of OVs enhances the oxidative efficiency of both photocatalysis and thermocatalysis, as well as the UV-Vis-IR photothermal catalytic performance. The ternary composite material generates weak hydroxyl (•OH) and superoxide (•O2-) radical under high-temperature with dark conditions, indicating its catalytic oxidation activity under this condition. The increase in temperature and the expansion of the spectral range both enhance the generation of these radicals. In summary, this work demonstrates that the use of diatomite as a support increases the material's specific surface area and OVs content, thereby enhancing adsorption and photothermal catalysis. It elucidates the enhanced catalytic degradation mechanism of this mineral-based photothermal catalyst.

18.
Biosens Bioelectron ; 267: 116778, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39270363

RESUMEN

Establishing an effective system to measure formaldehyde (HCHO) content in food is of great significance due to food safety concern. Inspired by the mechanism of HCHO-induced protein denaturation and its effect on ion/molecule transport in nanochannels, a bioinspired microchannel-based electrochemiluminescence (ECL) sensor was constructed for HCHO detection. Benefiting from the water solubility of HCHO, the molecules rapidly spread and enriched at the ethylenediamine (EDA) functionalized microchannel interface. The reaction between EDA and HCHO significantly increased the negative charge density, leading to enhanced electroosmotic flow (EOF). This enhancement resulted in ion concentration depletion at the microchannel tip and a corresponding decrease in ionic current and ECL intensity. The ECL intensity exhibited a linear dependence on the logarithm of HCHO concentration ranging from 1 pg mL-1 to 100 ng mL-1, with a detection limit of 0.26 pg mL-1(S/N = 3). The biosensor demonstrated high selectivity, successfully detecting HCHO in shrimp samples. The performance of the bioinspired sensor was confirmed through comparation with existing methods, showcasing its superior sensitivity and reliability. The bioinspired sensor provides robust technical support for HCHO detection, crucial for food safety monitoring. Additionally, the innovative combination of bionics and microchannel-based ECL technology broadens the application range of ECL sensors, marking a significant advancement in the field.

19.
Environ Sci Technol ; 58(37): 16368-16375, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39223712

RESUMEN

Assessment of personal formaldehyde (FA) exposure is most commonly carried out using formate as a biomarker, as it is the major product from FA metabolism. However, formate could also have originated from the metabolism of other endogenous and exogenous substances or from dietary intake, which may give rise to overestimated results with regard to FA exposure. We have developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with an isotope-dilution method for rigorous quantitation of two major urinary FA conjugation products: thioproline (SPro) and thioprolinyl glycine (SPro-Gly), formed in the reaction between FA and endogenous cysteine or cysteinyl glycine, respectively, as marker molecules to assess personal FA exposure. Using this newly developed method, we measured the FA exposure levels in cigarette smokers, occupants of a chemistry research laboratory and typical domestic household, and visitors to a Chinese temple with a Pearson correlation coefficient greater than 0.94, showing a strong linear correlation between urinary adduct levels and the airborne FA level. It is believed that quantitation of urinary SPro and SPro-Gly may represent a noninvasive, interference-free method for assessing personal FA exposure.


Asunto(s)
Biomarcadores , Formaldehído , Humanos , Biomarcadores/orina , Formaldehído/orina , Espectrometría de Masas en Tándem , Cromatografía Liquida , Glicina/análogos & derivados , Glicina/orina , Exposición a Riesgos Ambientales , Dipéptidos/orina , Tiazolidinas/orina
20.
Sci Total Environ ; 954: 176197, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39277005

RESUMEN

Monitoring the spatiotemporal distribution of formaldehyde (HCHO) is crucial for reducing volatile organic compounds (VOCs) emissions, and the long-term evolution of socio-natural sources contributions to tropospheric HCHO over China is still unclear. We propose an oversampling algorithm for quantitatively tracking the evolution of uncertainty, which lowers the uncertainty of the original Level 2 OMI HCHO data (50 % -105 %) to 0-50 %, and then we examine the evolution of contributions from various emissions sources applying multi-scale correlation. We found that the high formaldehyde vertical column densities (VCD) caused by human activities in eastern China are crossing the Hu Huanyong Line, which was formerly used to demarcate the population distribution. National-scale analysis indicate that HCHO VCD are significantly correlated with per capita Gross Domestic Product (per capita GDP) (r = 0.948) and Normalized Difference Vegetation Index (r = 0.864), while no substantial correlation with land surface temperature (LST) (r = 0.233). A valuable finding at city-scale is that the vast majority of cities exhibits clear latitude zoning characteristics in the correlation between HCHO VCD and per capita GDP. Diagnosis at pixel scale reveals that anthropogenic emissions continue to weaken the contributions of emissions caused by the increase in vegetation proportion. NDVI = 0.8 is the critical characteristic point where the contribution of natural source exceeds that of anthropogenic sources, while the point presents a decreasing trend in recent years due to the enhancement of human activities levels. Rise in LST over vegetation areas show positive driving effect on formaldehyde emissions, but continuous urbanization is diminishing this contribution. NDVI = 0.8 is a characteristic point to determine whether the contribution proportion of regional surface temperature to formaldehyde emissions from vegetation begun to rise. Our research identifies the evolutionary process and characteristics of the spatiotemporal distribution and socio-nature sources contributions of tropospheric formaldehyde of China from 2005 to 2022.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...