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1.
Nat Commun ; 15(1): 6074, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025911

RESUMEN

One-dimensional metallic transition-metal chalcogenide nanowires (TMC-NWs) hold promise for interconnecting devices built on two-dimensional (2D) transition-metal dichalcogenides, but only isotropic growth has so far been demonstrated. Here we show the direct patterning of highly oriented Mo6Te6 NWs in 2D molybdenum ditelluride (MoTe2) using graphite as confined encapsulation layers under external stimuli. The atomic structural transition is studied through in-situ electrical biasing the fabricated heterostructure in a scanning transmission electron microscope. Atomic resolution high-angle annular dark-field STEM images reveal that the conversion of Mo6Te6 NWs from MoTe2 occurs only along specific directions. Combined with first-principles calculations, we attribute the oriented growth to the local Joule-heating induced by electrical bias near the interface of the graphite-MoTe2 heterostructure and the confinement effect generated by graphite. Using the same strategy, we fabricate oriented NWs confined in graphite as lateral contact electrodes in the 2H-MoTe2 FET, achieving a low Schottky barrier of 11.5 meV, and low contact resistance of 43.7 Ω µm at the metal-NW interface. Our work introduces possible approaches to fabricate oriented NWs for interconnections in flexible 2D nanoelectronics through direct metal phase patterning.

2.
Angew Chem Int Ed Engl ; : e202409799, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039911

RESUMEN

Electrocatalytic nitrate reduction reaction (NO3-RR) is an important route for sustainable NH3 synthesis and environmental remediation. Metal-organic frameworks (MOFs) are one family of promising NO3-RR electrocatalysts, however, there is plenty of room to improve in their performance, calling for new design principles. Herein, a MOF-on-MOF heterostructured electrocatalyst with interfacial dual active sites and build-in electric field is fabricated for efficient NO3-RR to NH3 production. By growing Co-HHTP (HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) nanorods on Ni-BDC (BDC=1,4-benzenedicarboxylate) nanosheets, experimental and theoretical investigations demonstrate the formation of Ni-O-Co bonds at the interface of MOF-on-MOF heterostructure, leading to dual active sites tailed for NO3-RR. The Ni sites facilitate the adsorption and activation of NO3-, while the Co sites boost the H2O decomposition to supply active hydrogen (Hads) for N-containing intermediates hydrogenation on adjacent Ni sites, cooperatively reducing the energy barriers of NO3-RR process. Together with the accelerated electron transfer enabled by built-in electric field, remarkable NO3-RR performance is achieved with an NH3 yield rate of 11.46 mg h-1 cm-2 and a Faradaic efficiency of 98.4%, outperforming most reported MOF-based electrocatalysts. This work provides new insights into the design of high-performance NO3-RR electrocatalysts.

3.
Angew Chem Int Ed Engl ; : e202407840, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953248

RESUMEN

Noble gas xenon (Xe) is an excellent anesthetic gas, but its rarity, high cost and constrained production prohibits wide use in medicine. Here, we have developed a closed-circuit anesthetic Xe recovery and reusage process with highly effective CO2-specific adsorbent CUPMOF-5 that is promising to solve the anesthetic Xe supply problem. CUPMOF-5 possesses spacious cage cavities interconnected in four directions by confinement throat apertures of ~3.4 Å, which makes it an ideal molecular sieving of CO2 from Xe, O2, N2 with the benchmark selectivity and high uptake capacity of CO2. In-situ single-crystal X-ray diffraction (SCXRD) and computational simulation solidly revealed the vital sieving role of the confined throat and the sorbent-sorbate induced-fit strengthening binding interaction to CO2. CUPMOF-5 can remove 5% CO2 even from actual moist exhaled anesthetic gases, and achieves the highest Xe recovery rate (99.8%) so far, as verified by breakthrough experiments. This endows CUPMOF-5 great potential for the on-line CO2 removal and Xe recovery from anesthetic closed-circuits.

4.
Mar Environ Res ; 200: 106629, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-39008941

RESUMEN

Large quantities of marine ballast water discharged by ocean-going vessels can cause salinity increases in freshwater ports, which in turn negatively affects indigenous plankton in the ports. In this study, we investigated the impacts of marine ballast water discharge on the plankton community in a freshwater wharf through field surveys. It was found that salinity stress caused reductions in community indicators such as plankton community composition, abundance and diversity, thus threatening the structure and function of the plankton community in the wharf. In terms of the impact range, the salinity stress had a significant effect on all plankton in the waters near the discharge point and the phytoplankton in the waters 50 m from the discharge point, but had no significant effect on the plankton in the waters further away. Ballast water discharge also caused a significant decrease in the alpha diversity and richness of the plankton community but had no significant effect on the evenness of the plankton community. Moreover, phytoplankton were more tolerant of salinity changes than zooplankton in our study. This study provides an ecological reference for the scientific management of marine ballast water discharge and the risk of exogenous nutrient inputs to freshwater ecosystems.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38814599

RESUMEN

Objective: To assess the usefulness of combining positron emission tomography/computed tomography (PET/CT) with lung cancer autoantibody detection in identifying and managing lung nodules. Methods: The researchers identified 160 patients with pulmonary nodules admitted to their hospital between January 2018 and January 2021. These patients were designated as the experimental group. Additionally, 60 healthy individuals without pulmonary nodules were admitted to the hospital during the same period. The individuals constituted the control group. All study participants underwent digital PET/CT detection and had their lung cancer autoantibody levels determined through enzyme-linked immunosorbent assay. Further testing, such as puncture or surgical pathology, was performed for patients with lung nodules. The aim was to evaluate the significance of combining PET/CT with autoantibody detection in diagnosing and treating lung nodules. Results: The study found that testing multiple autoantibodies together increased sensitivity and accuracy compared to testing individual autoantibodies. Combining PET/CT screening with autoantibody detection improved the diagnostic rate for identifying lung nodules, including benign and suspected malignant ones. Several autoantibodies were significantly higher in the experimental group compared to the control group. Testing for multiple autoantibodies showed higher sensitivity and accuracy than testing for one. Pathological examination confirmed 129 benign nodules and 31 malignant nodules. The median SUVmax values were measured at 0.7 for benign nodules and 4.8 for malignant nodules. The diagnostic efficacy of PET/CT combined with autoantibodies was determined through comparison with pathology testing and was as follows: PET/CT combined with autoantibody detection > PET/CT > autoantibody detection. Conclusion: Combining PET/CT with the detection of autoantibodies enhances the positive diagnostic rate and accuracy of lung nodules in the case of lung cancer. The SUVmax also shows excellent potential as a supplement in diagnosing both benign and malignant lung nodules, providing valuable guidance in determining the pathological types.

6.
Chemosphere ; 356: 141952, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599329

RESUMEN

Photo-Fenton-like technology based on H2O2 is considered as an ideal strategy to generate reactive oxygen species (ROS) for antibiotic degradation, but O2 overflow in the process severely limits the utilization efficiency of H2O2. Herein, we fabricate Bi2MoO6 (BMO) photocatalyst modified with Frustrated Lewis pairs (FLPs) as a Fenton catalyst model for enhancing reuse of spilled O2. The FLPs created by the introduction of cerium and oxygen vacancy were found to contribute to regulate the electronic structure of BMO and further improve the acidic and basic properties of photocatalyst surface. More importantly, the frustrated acid and base sites can enhance the H2O2 and O2 interfacial adsorption process and provide an Ce4+-Ov-O2- active site on the surface of Ce-BMO nanosheets, which can promote O2/•O2-/1O2/H2O2 redox cycles to achieve high H2O2 utilization efficiency. Specifically, in the experiment using tetracycline as a photocatalytic degradation object, the degradation activity of Ce-BMO was 2.15 times higher than that of BMO pure phase. Quenching experiments and EPR assays also confirmed that 1O2 and •O2- were the dominant oxidative species. This study systematically reveals the design of Fenton photocatalytic active sites at the atomic scale and provides new insights into constructing FLPs photocatalysts with high H2O2 utilization efficiency.


Asunto(s)
Bismuto , Cerio , Peróxido de Hidrógeno , Fotólisis , Peróxido de Hidrógeno/química , Bismuto/química , Cerio/química , Catálisis , Molibdeno/química , Hierro/química , Especies Reactivas de Oxígeno/química , Oxidación-Reducción , Oxígeno/química
7.
Patient Prefer Adherence ; 18: 709-720, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38524198

RESUMEN

Background: Colorectal, and gastric cancers have the second, and fourth mortality rates worldwide, respectively. Endoscopic screening is a crucial diagnostic tool for colorectal, and gastric cancers. Effective interventions can improve adherence to endoscopic screening in high-risk populations, which is important for cancer prevention and mortality reduction. This study aimed to identify interventions that could improve adherence to endoscopic screening for cancer in high-risk populations. Methods: Combination keywords including colorectal cancer, gastric cancer, screening adherence, and interventions were used to search for articles in PubMed, Web of Science, Cochrane Library, and MEDLINE Complete. The review methodology was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-SCR). Results: A total of 12 articles were included in this review: 9 randomized controlled trials(RCT) and 3 quasi-experimental studies(QEDs). Among the extracted studies, 11 were about colorectal cancer, and 1 was about gastric cancer. Most studies used lecture-based or Information Technology-based health education interventions. Narrative interventions have proven to be novel and effective approaches for promoting adherence to endoscopic screening. Health education interventions included cancer epidemiology, cancer risk factors, warning symptoms, and screening methods. Conclusion: All interventions involved were effective in increasing individual knowledge of cancer-related endoscopic screening, willingness to undergo screening, and screening behaviors. These findings provide a reference for designing endoscopy-related cancer screening interventions.

8.
Curr Med Imaging ; 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38494941

RESUMEN

BACKGROUND: Coronary Heart Disease (CHD) is one of the most common types of cardiovascular disease, and Heart Failure (HF) is an important factor in its progression. We aimed to evaluate the diagnostic value and predictors of multiparametric Cardiac Magnetic Resonance (CMR) in CHD patients with HF. METHODS: The study retrospectively included 145 CHD patients who were classified into CHD (HF+) (n = 91) and CHD (HF-) (n = 54) groups according to whether HF occurred. CMR assessed LV function, myocardial strain and T1 mapping. Multivariate linear regression analyses were performed to identify predictors of LV dysfunction, myocardial fibrosis, and LV remodeling. RESULTS: CHD (HF+) group had impaired strain, with increased native T1, ECV, and LVM index. The impaired strain was associated with LVM index (p < 0.05), where native T1 and ECV were affected by log-transformed amino-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. ROC analysis showed the combination of global circumferential strain (GCS), native T1, and LVM had a higher diagnostic value for the occurrence of HF in CHD patients.

Meanwhile, log-transformed NT-proBNP was an independent determinant of impaired strain, increased LVM index, native T1 and ECV. CONCLUSION: HF has harmful effects on LV systolic function in patients with CHD. In CHD (HF+) group, LV dysfunction is strongly correlated with the degree of LV remodeling and myocardial fibrosis. The combination of the three is more valuable in diagnosing HF than conventional indicators.

9.
Dev Cell ; 59(9): 1175-1191.e7, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38521055

RESUMEN

In pyloric metaplasia, mature gastric chief cells reprogram via an evolutionarily conserved process termed paligenosis to re-enter the cell cycle and become spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Here, we use single-cell RNA sequencing (scRNA-seq) following injury to the murine stomach to analyze mechanisms governing paligenosis at high resolution. Injury causes induced reactive oxygen species (ROS) with coordinated changes in mitochondrial activity and cellular metabolism, requiring the transcriptional mitochondrial regulator Ppargc1a (Pgc1α) and ROS regulator Nf2el2 (Nrf2). Loss of the ROS and mitochondrial control in Ppargc1a-/- mice causes the death of paligenotic cells through ferroptosis. Blocking the cystine transporter SLC7A11(xCT), which is critical in lipid radical detoxification through glutathione peroxidase 4 (GPX4), also increases ferroptosis. Finally, we show that PGC1α-mediated ROS and mitochondrial changes also underlie the paligenosis of pancreatic acinar cells. Altogether, the results detail how metabolic and mitochondrial changes are necessary for injury response, regeneration, and metaplasia in the stomach.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Ferroptosis , Metaplasia , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Especies Reactivas de Oxígeno , Regeneración , Estómago , Animales , Especies Reactivas de Oxígeno/metabolismo , Ratones , Ferroptosis/fisiología , Estómago/patología , Regeneración/fisiología , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Metaplasia/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Mitocondrias/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Mucosa Gástrica/metabolismo , Ratones Endogámicos C57BL , Células Principales Gástricas/metabolismo , Células Acinares/metabolismo , Ratones Noqueados , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Péptidos y Proteínas de Señalización Intercelular
11.
Anal Chim Acta ; 1290: 342202, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38246745

RESUMEN

BACKGROUND: Lanthanide metal-organic frameworks (Ln-MOFs) are a kind of emerging crystalline porous materials with high fluorescence and easy-to-tunable properties, making them ideal for sensing applications. However, current Ln-MOFs based fluorescent probes are primarily single-emissive or fluorescence-quenched, which greatly limited the detection performances such as sensitivity, accuracy and repeatability, thereby hindering their applications in efficient target monitoring and related disease diagnosis. To address these issues, the reasonable design of Ln-MOFs equipped with dual fluorescence emissions and light-up mode is urgently needed for a high-performance biosensor. RESULTS: A dual-emissive europium doped UiO-66 (Eu@UiO-66-NH2-PMA)-based ratiometric fluorescent biosensing platform was constructed for highly sensitive and selective detection of the histidinemia biomarker-histidine (His). Eu@UiO-66-NH2-PMA (pyromellitic acid abbreviated as PMA) was synthesized utilizing a post-synthetic modification method via coordination interactions between the free -COOH of UiO-66-NH2-PMA and Eu3+, which exhibited characteristic peaks of broad ligand emission and sharp Eu3+ emissions simultaneously. Considering that Cu2+ had the excellent fluorescence quenching ability toward Eu3+ and superior affinity with His, it was deliberately introduced into the Eu@UiO-66-NH2-PMA, acting as active sites for target His responsiveness. The Eu@UiO-66-NH2-PMA/Cu2+/His ternary competition system demonstrated a low detection limit of 74 nM, excellent selectivity and good anti-interference capability that allowed for sensitive analysis of His levels in milk and human serum samples. SIGNIFICANCE: Attributing to the superior luminescent properties, good stability and self-calibration capability of Eu@UiO-66-NH2-PMA, the developed ratiometric light-up sensing platform enabled sensitive, selective and credible analysis of His in complex practical samples, which might provide an available tool for food nutrition guideline and diagnostic applications of His related diseases.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos , Europio , Histidina Amoníaco-Liasa/deficiencia , Elementos de la Serie de los Lantanoides , Estructuras Metalorgánicas , Ácidos Ftálicos , Humanos , Histidina , Biomarcadores , Colorantes Fluorescentes
12.
Nanotechnology ; 35(13)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37995369

RESUMEN

Flexible solid-state zinc-air batteries as a wearable energy storage device with great potential, and their separators, which control ion permeability, inhibit zinc dendrite generation, and regulate catalytic active sites, have been developed as gel electrolyte separators with high retention of electrolyte uptake. However, the gel electrolyte separator still has problems such as poor affinity with the electrolyte and poor ionic conductivity, which limits its further application. In order to further improve the electrolyte absorption, ionic conductivity and mechanical strength of cellulose acetate(CA)/polyvinyl alcohol (PVA) nanofibers, TiO2was added to CA/PVA to increase the porosity, and glutaraldehyde (GA) was used to modify the CA/PVA/TiO2separator by acetal reaction with CA and PVA to make the molecules closely linked. The results shows that the optimal mass fractions of TiO2and GA were 2% and 5%, respectively. At this time, the porosity and absorption rate of the separator increased from 48% to 68.2% and 142.4% to 285.3%, respectively. The discharge capacity reached 179 mA cm-3, and the cycle stability rate was 89% after 7 stable constant current charge/discharge cycles.

13.
Int Emerg Nurs ; 72: 101387, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37984024

RESUMEN

BACKGROUND: Emergency nurses are a professional group at a high risk of burnout and depression. This may influence their mental state and physical health. AIMS: The aim of the study was to explore the relationship between role stress, occupational burnout and depression among emergency nurses. METHODS: A cross-sectional study was carried out among 295 emergency nurses from eight tertiary hospitals in western China. The Role Stress Scale, the Maslach Burnout Inventory-Human Services Survey and the Center for Epidemiologic Studies Depression Scale were employed. Descriptive statistics, independent sample t-tests, one-way analysis of variance, Pearson's correlation analysis and regression analysis were performed. RESULTS: Of the study participants, 54.6% were found to have depressive symptoms and 48.1% had severe occupational burnout. Positive correlations were observed between the scores of role stress and burnout and depression. Approximately 37.1% of the variation in depression was explained by the components of occupational burnout. CONCLUSIONS: Emergency nurses experience high levels of role stress, occupational burnout and depression. Preventive approaches to role stress, burnout and depression are needed to improve their psychological condition and quality of work life.


Asunto(s)
Agotamiento Profesional , Personal de Enfermería en Hospital , Pruebas Psicológicas , Autoinforme , Humanos , Agotamiento Profesional/epidemiología , Agotamiento Profesional/etiología , Agotamiento Profesional/psicología , Estudios Transversales , Depresión/etiología , Personal de Enfermería en Hospital/psicología , Encuestas y Cuestionarios
14.
Nano Lett ; 24(1): 16-25, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38109350

RESUMEN

The anomalous Hall effect (AHE) is an important transport signature revealing topological properties of magnetic materials and their spin textures. Recently, MnBi2Te4 has been demonstrated to be an intrinsic magnetic topological insulator. However, the origin of its intriguing AHE behaviors remains elusive. Here, we demonstrate the Berry curvature-dominated intrinsic AHE in wafer-scale MnBi2Te4 films. By applying back-gate voltages, we observe an ambipolar conduction and n-p transition in ∼7-layer MnBi2Te4, where a quadratic relation between the AHE resistance and longitudinal resistance suggests its intrinsic AHE nature. In particular, for ∼3-layer MnBi2Te4, the AHE sign can be tuned from pristine negative to positive. First-principles calculations unveil that such an AHE reversal originated from the competing Berry curvature between oppositely polarized spin-minority-dominated surface states and spin-majority-dominated inner bands. Our results shed light on the underlying physical mechanism of the intrinsic AHE and provide new perspectives for the unconventional sign-tunable AHE.

15.
Front Public Health ; 11: 1128765, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38089026

RESUMEN

Objectives: The efficacy of updated health policy in improving the generalization of Helicobacter pylori screening and eradication in southwest China was assessed in a longitudinal analysis of multiple cross-sectional studies from an institution. Methods: In the periods 2009-2010, 2013-2014, and 2019-2021, 8,365, 16,914, and 18,281 urban observations from health check-ups at West China Hospital were analyzed, respectively. The 14C-urea or 13C-urea breath test was consistently used for H. pylori detection. The protocol has been reported elsewhere (PROSPERO Registration number: CRD42019120764). Results: The overall prevalence of H. pylori dramatically decreased from 53.1% to 30.7% over the past decade (OR = 0.39, 95% CI 0.37-0.41), with a similar decline in all sex-specific and age-specific subgroups. The age-specific prevalence consistently increased before 40 years of age and always peaked at 50-59 years. Longitudinal clearance increased along with aging, and prevalence dropped to 22.6%, 25.1%, and 23.6% in the 40-49, 50-59, and 60-69 years initial age groups, respectively. Conclusion: The generalization of H. pylori screening and eradication could greatly contribute to the control of H. pylori infection among urban health check-up populations and lower gastric cancer incidence.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Masculino , Femenino , Humanos , Adulto , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/diagnóstico , Estudios Transversales , Prevalencia , Salud Urbana , China/epidemiología , Urea
16.
iScience ; 26(10): 107964, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37810219

RESUMEN

The Polycomb group protein SCML2 and the transcriptional cofactor YAP1 regulate diverse cellular biology, including stem cell maintenance, developmental processes, and gene regulation in mammals and flies. However, their molecular and functional interactions are unknown. Here, we show that SCML2 interacts with YAP1, as revealed by immunological assays and mass spectroscopy. We have demonstrated that the steroid hormone androgen regulates the interaction of SCML2 with YAP1 in human tumor cell models. Our proximity ligation assay and GST pulldown showed that SCML2 and YAP1 physically interacted with each other. Silencing SCML2 by RNAi changed the growth behaviors of cells in response to androgen signaling. Mechanistically, this phenomenon is attributed to the interplay between distinct chromatin modifications and transcriptional programs, likely coordinated by the opposing SCML2 and YAP1 activity. These findings suggest that YAP1 and SCML2 cooperate to regulate cell growth, cell survival, and tumor biology downstream of steroid hormones.

17.
Environ Sci Pollut Res Int ; 30(46): 102790-102802, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37672159

RESUMEN

Air pollution is a major public health problem that can lead to conjunctivitis. This study aimed to explore the associations between air pollutants and outpatient visits for conjunctivitis in Hangzhou, China. This study collected data on 50,772 patients with conjunctivitis and the concentrations of six air pollutants from February 1, 2014, to August 31, 2018. A time series analysis using a generalized additive model (GAM) was conducted. We found that the risk of conjunctivitis was related to the air pollutants PM2.5, PM10, SO2, NO2, and O3, which had concentration hysteresis effects. The risk of conjunctivitis increased by 1.009 (95% confidence interval (CI): 1.003, 1.014), 1.011 (95% CI: 1.008, 1.015), 1.238 (95% CI: 1.186, 1.292), 1.028 (95% CI: 1.019, 1.038), and 1.013 (95% CI: 1.008, 1.017) for every 10 µg/m3 increase in PM2.5, PM10, SO2, NO2, and O3 concentrations, respectively. The lag effects of SO2 and NO2 were stronger than those of particulate matter. Females exposed to PM10, PM2.5, SO2, and O3 had a higher risk of conjunctivitis than males, while males exposed to NO2 had a nearly identical risk of conjunctivitis as females. People aged 19-59 were more likely to suffer from conjunctivitis. The risk of conjunctivitis caused by PM10, SO2, and O3 was highest in the transitional season, while the risk caused by NO2 was highest in the winter season. In conclusion, females and middle-aged adults were at higher risk of conjunctivitis. People were more susceptible to conjunctivitis during the transitional season. These findings highlight the importance of atmospheric pollution governance and reference for public health measures.

18.
Nanotechnology ; 34(50)2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37725965

RESUMEN

In this work, an electrochemical sensor based on ion-imprinted polymer/Au nanoparticles/porous biochar (IIP/AuNPs/PBC) composite was proposed for the highly selective and sensitive detection of Pb2+. In this work, poly (thionine) (pTHI) served simultaneously as imprinted polymer and reference probe. It could not only realize the specific detection of Pb2+, but also provide an internal reference signal to eliminate the influence of human and environmental factors on the detection signal and further improve the stability of the sensor. In addition, the AuNPs/PBC composite with large specific surface area, excellent electron transport and electrocatalytic performance could effectively enhance the detection signal as a carrier material. At the same time, the AuNPs on the PBC surface would promote the formation of uniform and stable IIP through Au-S bonds. The synergistic effect between IIP, AuNPs/PBC and ratiometric signal mode gave the Pb2+sensor excellent performance, including a wide linear range (0.1-1000µg l-1), low detection limit (0.03µg l-1, S/N = 3), excellent selectivity and stability. All these results indicate that the proposed sensor could provide a meaningful reference for highly selective detection of heavy metal ions (HMIs).

19.
Nat Commun ; 14(1): 5780, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37723168

RESUMEN

Construction of two-dimensional nanosheets into three-dimensional regular structures facilitates the mass transfer and exploits the maximum potential of two-dimensional building blocks in applications such as catalysis. Here, we report the synthesis of metal-organic frameworks with an orthogonal nanosheet array. The assembly involves the epitaxial growth of single crystalline metal-organic framework nanosheets with a naturally non-preferred facet exposure as the shell on a cubic metal-organic framework as the core. The nanosheets, despite of two typical shapes and crystallographic orientations, also form a single crystalline orthogonally arrayed framework. The density and size of nanosheets in the core-shell-structured composite metal-organic frameworks can be well adjusted. Moreover, metal-organic frameworks with a single composition and hollow orthogonal nanosheet array morphology can be obtained. Benefiting from the unusual facet exposure and macroporous structure, the designed structure exhibits improved electrocatalytic oxygen evolution activity compared to conventional nanosheets.

20.
Chemosphere ; 340: 139728, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37557997

RESUMEN

The electrochemical technique has been increasingly used for the detection of heavy metal ions in the water system. However, the process for determining the optimum experimental conditions was cumbersome, time-consuming, and unsynchronized, resulting in unsatisfactory detection efficiency. Herein, a new machine learning (ML) strategy combined with BiFeO3/Ti3C2 MXene (BiFeO3/MXene) was used to fabricate a simple but efficient electrochemical Pb2+ sensor. The interconnected BiFeO3/MXene composites prepared by a hydrothermal method possessed an interconnected conductive framework, abundant active sites, and a large surface area, which gave them excellent electronic conductivity and high accumulation of Pb2+. Meanwhile, ML methods such as back-propagation artificial neural network (BPANN) and genetic algorithm (GA) combined with orthogonal experimental design (OED) were used to optimize sensor parameters such as the pH of the supporting electrolyte, the BiFeO3/MXene content, deposition potential, and deposition time. Compared with OED and the one factor at a time (OFAT) methods, the OED-ML method greatly simplified the experimental procedures and improved the electrochemical detection performance. The developed sensor showed superior detection performance for Pb2+ with a detection limit of 0.0001 µg L-1 using the OED-ML method, which was much lower than that of the OED and OFAT methods (0.0003 µg L-1). In addition, the sensor showed good repeatability, reproducibility, stability, and interference capability. The feasibility of the method was verified by detecting Pb2+ in lake samples with recoveries ranging from 98.79% to 101.3%. To our knowledge, the ML strategy was introduced for the first time in an electrochemical sensor for Pb2+ detection, which proved the feasibility and practicality of ML.


Asunto(s)
Plomo , Titanio , Reproducibilidad de los Resultados , Técnicas Electroquímicas , Aprendizaje Automático
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