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1.
BMC Med Imaging ; 24(1): 102, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724896

RESUMEN

Precision and intelligence in evaluating the complexities of middle ear structures are required to diagnose auriculotemporal and ossicle-related diseases within otolaryngology. Due to the complexity of the anatomical details and the varied etiologies of illnesses such as trauma, chronic otitis media, and congenital anomalies, traditional diagnostic procedures may not yield accurate diagnoses. This research intends to enhance the diagnosis of diseases of the auriculotemporal region and ossicles by combining High-Resolution Spiral Computed Tomography (HRSCT) scanning with Deep Learning Techniques (DLT). This study employs a deep learning method, Convolutional Neural Network-UNet (CNN-UNet), to extract sub-pixel information from medical photos. This method equips doctors and researchers with cutting-edge resources, leading to groundbreaking discoveries and better patient healthcare. The research effort is the interaction between the CNN-UNet model and high-resolution Computed Tomography (CT) scans, automating activities including ossicle segmentation, fracture detection, and disruption cause classification, accelerating the diagnostic process and increasing clinical decision-making. The suggested HRSCT-DLT model represents the integration of high-resolution spiral CT scans with the CNN-UNet model, which has been fine-tuned to address the nuances of auriculotemporal and ossicular diseases. This novel combination improves diagnostic efficiency and our overall understanding of these intricate diseases. The results of this study highlight the promise of combining high-resolution CT scanning with the CNN-UNet model in otolaryngology, paving the way for more accurate diagnosis and more individualized treatment plans for patients experiencing auriculotemporal and ossicle-related disruptions.


Asunto(s)
Osículos del Oído , Tomografía Computarizada Espiral , Humanos , Tomografía Computarizada Espiral/métodos , Osículos del Oído/diagnóstico por imagen , Aprendizaje Profundo , Enfermedades del Oído/diagnóstico por imagen , Hueso Temporal/diagnóstico por imagen , Adulto , Redes Neurales de la Computación
2.
ACS Nano ; 18(20): 13286-13297, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38728215

RESUMEN

The ideal interface design between the metal and substrate is crucial in determining the overall performance of the alkyne semihydrogenation reaction. Single-atom alloys (SAAs) with isolated dispersed active centers are ideal media for the study of reaction effects. Herein, a charge-asymmetry "armor" SAA (named Pd1Fe SAA@PC), which consists of a Pd1Fe alloy core and a semiconducting P-doped C (PC) shell, is rationally designed as an ideal catalyst for the selective hydrogenation of alkynes with high efficiency. Multiple spectroscopic analyses and density functional theory calculations have demonstrated that Pd1Fe SAA@PC is dual-regulated by lattice tensile and Schottky effects, which govern the selectivity and activity of hydrogenation, respectively. (1) The PC shell layer applied an external traction force causing a 1.2% tensile strain inside the Pd1Fe alloy to increase the reaction selectivity. (2) P doping into the C-shell layer realized a transition from a p-type semiconductor to an n-type semiconductor, thereby forming a unique Schottky junction for advancing alkyne semihydrogenation activity. The dual regulation of lattice strain and the Schottky effect ensures the excellent performance of Pd1Fe SAA@PC in the semihydrogenation reaction of phenylethylene, achieving a conversion rate of 99.9% and a selectivity of 98.9% at 4 min. These well-defined interface modulation strategies offer a practical approach for the rational design and performance optimization of semihydrogenation catalysts.

3.
Vet Sci ; 11(5)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38787175

RESUMEN

Several trichomonad species have already been identified in pigs, and their pathogenic potential may not be ruled out. To date, however, no information is available regarding the prevalence of trichomonads in pigs in Shanxi Province, North China. In the present study, a total of 362 fecal samples collected from pigs in three representative counties (Qi, Jishan, and Shanyin) in this province were examined for Tetratrichomonas buttreyi, Tritrichomonas foetus, and Pentatrichomonas hominis using a nested polymerase chain reaction (PCR) with primers targeting the small subunit ribosomal RNA (SSU rRNA) gene. The overall prevalence of T. buttreyi was 49.72%, and region and age were found to be significantly associated with T. buttreyi infection, respectively. Only one pig fecal sample from Qi County was found to be positive for T. foetus, and all samples were negative for P. hominis. Molecular evolutionary analysis revealed that some T. buttreyi isolates showed complete genetic identity with those reported previously, and some T. buttreyi isolates and one T. foetus isolate showed minor allelic variations compared with those reported previously. This is the report of the molecular epidemiology of T. foetus and T. buttreyi in pigs in Shanxi Province, North China. These findings not only enrich the knowledge on the distribution of these trichomonad species in pigs in China but also provide baseline information for planning future research and control strategies.

4.
J Am Chem Soc ; 146(21): 14898-14904, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38749059

RESUMEN

The electrocatalytic reduction of nitrate is promising for sustainable ammonia synthesis but suffers from slow reduction kinetics and multiple competing reactions. Here, we report a catalyst featuring copper nitride (Cu3N) anchored on a novel graphdiyne support (termed Cu3N/GDY), which is used for electrocatalytic reduction of nitrate to produce ammonia. The GDY absorbed hydrogen and enabled nitrogen (N) vacancy formation in Cu3N for the fast nitrate reduction reaction (NO3RR). Further, the distinct absorption sites formed by GDY and N vacancy enabled the excellent selectivity and stability of NO3RR. Notably, the Cu3N/GDY catalyst achieved a high ammonia yield (YNH3) up to 35280 µg h-1 mgcat.-1 and a high Faradaic efficiency (FE) of 98.1% using 0.1 M NO3- at -0.9 V versus a reversible hydrogen electrode (RHE). Using electron paramagnetic resonance (EPR) technology and in situ X-ray absorption fine structure (XAFS) spectroscopy measurement, we visualized the N vacancy formation in Cu3N and electrocatalytic NO3RR enabled by GDY. These findings show the promise of GDY in sustainable ammonia synthesis and highlight the efficacy of Cu3N/GDY as a catalyst.

5.
Angew Chem Int Ed Engl ; : e202402684, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597346

RESUMEN

Electrocatalytic urea synthesis under ambient conditions offers a promising alternative strategy to the traditional energy-intensive urea industry protocol. Limited by the electrostatic interaction, the reduction reaction of anions at the cathode in the electrocatalytic system is not easily achievable. Here, we propose a novel strategy to overcome electrostatic interaction via pulsed electroreduction. We found that the reconstruction-resistant CuSiOx nanotube, with abundant atomic Cu-O-Si interfacial sites, exhibits ultrastability in the electrosynthesis of urea from nitrate and CO2. Under a pulsed potential approach with optimal operating conditions, the Cu-O-Si interfaces achieve a superior urea production rate (1606.1 µg h-1 mgcat. -1) with high selectivity (79.01 %) and stability (the Faradaic efficiency is retained at 80 % even after 80 h of testing), outperforming most reported electrocatalytic synthesis urea catalysts. We believe our strategy will incite further investigation into pulsed electroreduction increasing substrate transport, which may guide the design of ambient urea electrosynthesis and other energy conversion systems.

6.
Adv Mater ; : e2401055, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38569116

RESUMEN

Atomic metal catalysts have unique electronic, structural, and catalytic properties, which are widely used in the field of catalysis. However, designing new simple synthesis methods to fabricate atomic metal catalysts is a challenge in catalytic applications. Herein, a one-step precursor combustion strategy is presented that starts directly from precursors of metal salts, using a spontaneous combustion process convert platinum nitrate to atomic Pt sites. The atomic Pt sites with low valence are anchored in the formed interface between grains on vacancy-enriched CeO2 nanosheets. The obtained Pt/CeO2-2 catalyst exhibits much higher three-way catalytic activities at low temperatures than Pt/CeO2-C catalysts prepared using the traditional impregnation method. Density functional theory calculations show that the generated lower valent Pt atoms in the CeO2 interface promote catalytic activity through reducing the energy barrier, and lead to an overall improvement of three-way catalytic activities. This facile strategy provides new insights into the study of the properties and applications of atomic noble metal catalysts.

7.
Behav Sci (Basel) ; 14(3)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38540517

RESUMEN

A positive child-teacher relationship is a crucial means of addressing problem behaviors in young children. In recent years, there has been an increase in factors triggering problem behaviors in young children. It is particularly important to employ universally applicable and scientifically effective strategies to improve child behavior. Banking Time, as an emerging variant of play therapy, aims to enhance child behavior by establishing an intimate child-teacher relationship. This study conducted a multiple-baseline experiment involving eight four-year-old children and their teachers from China, exploring the effectiveness of Banking Time in enhancing child-teacher relationships and subsequently improving child behavior from dual perspectives, utilizing tools such as the Student-Teacher Relationship Scale and Conners' Comprehensive Behavior Rating Scales-Teacher Assessment Report. Visual analysis and statistical analysis results indicate a strong positive impact of Banking Time on child-teacher relationships and a slight inhibitory effect on child problem behaviors. The implementation of Banking Time provides valuable insights into specific paths and strategies for promoting teachers' professional development.

8.
Front Psychol ; 15: 1321441, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38414879

RESUMEN

Objective: Frequent teacher turnover may damage the development of teachers and the regular operation of kindergartens. This original research presented kindergarten teachers' first, second, and third turnover rates and occurrence times. This research analyzed the relationship between socio-demographic variables and the varying frequency of kindergarten teacher turnover. These data were used to investigate the characteristics of first, second, and third kindergarten turnover. This research evaluated kindergarten teachers' occupational ambition, emotional attachment, and self-efficacy. Likewise, this research also analyzed the social context, organizational support, management mechanism, reward, and occupational stress of kindergarten. These data were used to determine the key factors affecting kindergarten teachers' turnover. Methods: This research recruited 1,118 kindergarten teachers (mean age = 31.67, sd = 5.02; 3.85% male, 96.14% female) from China. Based on the existing scales, this research developed the Questionnaire of Kindergarten Teachers' Turnover and Influencing Factors for the survey. Kindergarten teachers reported basic information and the impact factors of their first, second, and third turnover through online questionnaires. The Chi-square test was used to analyze the correlation between socio-demographic variables and different frequencies of kindergarten teacher turnover. The binary logistic regression explored the eight factors affecting kindergarten teachers' first, second, and third turnover. Results: The results showed that 43.65% of kindergarten teachers had resigned. In detail, 25.60% of kindergarten teachers resigned once, 10.64% of kindergarten teachers resigned twice, and 8.41% of kindergarten teachers resigned thrice. Gender and marital status were significantly correlated with the three frequencies of kindergarten teacher turnover. Occupational stress, reward, management mechanisms, and ambition consistently affected kindergarten teachers' first, second, and third turnover. Conclusion: The relevant management departments should pay attention to the high turnover rate of kindergarten teachers and put forward more strategies to improve their stability. Women and married can be favored in the recruitment of kindergarten teachers. It is crucial to reduce pressure and improve rewards for kindergarten teachers. Also, kindergartens should provide the space to display teachers' talents and improve management mechanisms. These results provide empirical support for proposing effective policies to promote the stability of kindergarten teachers' construction.

9.
Angew Chem Int Ed Engl ; 63(3): e202316123, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37997525

RESUMEN

Modulating the surface and spatial structure of the host is associated with the reactivity of the active site, and also enhances the mass transfer effect of the CO2 electroreduction process (CO2 RR). Herein, we describe the development of two-step ligand etch-pyrolysis to access an asymmetric dual-atomic-site catalyst (DASC) composed of a yolk-shell carbon framework (Zn1 Mn1 -SNC) derived from S,N-coordinated Zn-Mn dimers anchored on a metal-organic framework (MOF). In Zn1 Mn1 -SNC, the electronic effects of the S/N-Zn-Mn-S/N configuration are tailored by strong interactions between Zn-Mn dual sites and co-coordination with S/N atoms, rendering structural stability and atomic distribution. In an H-cell, the Zn1 Mn1 -SNC DASC shows a low onset overpotential of 50 mV and high CO Faraday efficiency of 97 % with a low applied overpotential of 343 mV, thus outperforming counterparts, and in a flow cell, it also reaches a high current density of 500 mA cm-2 at -0.85 V, benefitting from the high structure accessibility and active dual sites. DFT simulations showed that the S,N-coordinated Zn-Mn diatomic site with optimal adsorption strength of COOH* lowers the reaction energy barrier, thus boosting the intrinsic CO2 RR activity on DASC. The structure-property correlation found in this study suggests new ideas for the development of highly accessible atomic catalysts.

10.
Animals (Basel) ; 13(24)2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38136808

RESUMEN

Giardia duodenalis is a ubiquitous flagellated protozoan, causing significant economic losses to animal husbandry and posing threats to public health. China ranks the world's sixth largest major producer of donkeys, rearing approximately 2.6 million donkeys in 2019, but limited investigation of G. duodenalis prevalence has been conducted in the past, and it is yet to be known whether donkeys in Shanxi Province are infected with G. duodenalis. In the present study, a total of 815 fecal samples collected from donkeys in representative regions of Shanxi Province, North China, were examined for G. duodenalis using nested PCR. Then, the assemblages and multilocus genotypes (MLGs) were examined based on three established loci: namely, ß-giardin (bg), triosephosphate isomerase (tpi), and glutamate dehydrogenase (gdh). The overall prevalence of G. duodenalis in donkeys in Shanxi Province was 16.81% (137/815). The region was identified as the main risk factor for the observed difference in G. duodenalis prevalence in donkeys among the three study areas (χ2 = 21.611, p < 0.001). Assemblages A, E, and B were identified, with the latter as the predominant assemblage. Three MLGs (MLG-novel-1 to 3) were formed based on sequence variation among the three loci. The present study reveals the presence of G. duodenalis in donkeys in Shanxi Province, North China, for the first time, which not only enriches the data on the distribution of G. duodenalis in donkeys in China but also provides useful baseline data for planning control strategies against G. duodenalis infection in the sampled areas.

11.
ACS Nano ; 17(21): 21838-21849, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37909679

RESUMEN

The electrochemical nitrogen reduction reaction (eNRR) under mild conditions emerges as a promising approach to produce ammonia (NH3) compared to the typical Haber-Bosch process. Herein, we design an asymmetrically coordinated p-block antimony single-atom catalyst immobilized on nitrogen-doped Ti3C2Tx (Sb SA/N-Ti3C2Tx) for eNRR, which exhibits ultrahigh NH3 yield (108.3 µg h-1 mgcat-1) and excellent Faradaic efficiency (41.2%) at -0.3 V vs RHE. Complementary in situ spectroscopies with theoretical calculations reveal that the nitrogen-bridged two titanium atoms triggered by an adjacent asymmetrical Sb-N1C2 moiety act as the active sites for facilitating the protonation of the rate-determining step from *N2 to *N2H and the kinetic conversion of key intermediates during eNRR. Moreover, the introduction of Sb-N1C2 promotes the formation of oxygen vacancies to expose more titanium sites. This work presents a strategy for single-atom-decorated ultrathin two-dimensional materials with the aim of simultaneously enhancing NH3 yield and Faradaic efficiency for electrocatalytic nitrogen reduction.

12.
J Am Chem Soc ; 145(41): 22836-22844, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37794780

RESUMEN

Mixed plastic waste treatment has long been a significant challenge due to complex composition and sorting costs. In this study, we have achieved a breakthrough in converting mixed plastic wastes into a single chemical product using our innovative single-atom catalysts for the first time. The single-atom Ru catalyst can convert ∼90% of real mixed plastic wastes into methane products (selectivity >99%). The unique electronic structure of Ru sites regulates the adsorption energy of mixed plastic intermediates, leading to rapid decomposition of mixed plastics and superior cycle stability compared to traditional nanocatalysts. The global warming potential of the entire process was evaluated. Our proposed carbon-reducing process utilizing single-atom catalysts launches a new era of mixed plastic waste valorization.

13.
J Am Chem Soc ; 145(40): 22069-22078, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37774141

RESUMEN

As a commercial electrode material for proton-exchange membrane water electrolyzers and fuel cells, Pt-based catalysts still face thorny issues, such as insufficient mass activity, stability, and CO tolerance. Here, we construct a bifunctional catalyst consisting of Pt-Er alloy clusters and atomically dispersed Pt and Er single atoms, which exhibits excellent activity, durability, and CO tolerance of acidic hydrogen evolution and oxidation reactions (HER and HOR). The catalyst possesses a remarkably high mass activity and TOF for HER at 63.9 times and 7.2 times more than that of Pt/C, respectively. More impressively, it can operate stably in the acidic electrolyte at 1000 mA cm-2 for more than 1200 h, thereby confirming its potential for practical applications at the industrial current density. In addition, the catalyst also demonstrates a distinguished HOR performance and outstanding CO tolerance. The synergistic effects of active sites give the catalyst exceptional activity for the hydrogen reaction, while the introduction of Er atoms greatly enhances its stability and CO tolerance. This work provides a promising idea for designing low-Pt-loading acidic HER electrocatalysts that are durable at ampere-level current densities and for constructing HOR catalysts with high CO tolerance.

14.
Anal Chem ; 95(37): 13880-13888, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37677106

RESUMEN

The physicochemical properties of nanoparticles (NPs) significantly influence their deposition at the disease site, ultimately impacting the overall therapeutic efficacy; however, precisely assessing the effects of various factors on NP accumulation within a single cell/tumor tissue is challenging due to the lack of appropriate labeling techniques. Surface-enhanced Raman spectroscopy (SERS) tag is a powerful encoding method that has recently been intensively employed for immunodetection of biomarkers. Herein, we introduce a multiplexed SERS tracking approach for systematic investigation of size-dependent accumulation and distribution of NPs within the same tumor. Four-sized (34, 60, 108, and 147 nm) NPs encoded with different SERS "colors" were fabricated, mixed, and incubated with monolayer tumor cells, multicellular tumor spheroids, or injected into mouse models bearing xenograft solid tumors in a single dose. Multicolor SERS detection of the specimens revealed that NP accumulation in tumor cells, tumor spheroids, and solid tumors was in the order of 34 nm > 60 nm > 108 nm > 147 nm, 60 nm > 34 nm > 108 nm > 147 nm, and 34 nm > 147 nm > 108 nm > 60 nm, respectively. Inductively coupled plasma mass spectroscopy determination performed in parallel samples were in alignment with the four-color SERS probing results, demonstrating the effectiveness of this multiplexed evaluation assay. Furthermore, in combination with fluorescence labeling of specific biomolecules, this method can be applied for the colocalization of different NPs in various pathological structures and provide additional information for analysis of the possible mechanisms.


Asunto(s)
Nanopartículas , Neoplasias , Animales , Humanos , Ratones , Modelos Animales de Enfermedad , Espectrometría Raman
15.
Adv Mater ; 35(41): e2304130, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37403556

RESUMEN

The selective hydrogenation of alkynes is an important reaction; however, the catalytic activity and selectivity in this reaction are generally conflicting. In this study, ultrafine Pd nanoparticles (NPs) loaded on a graphite-like C3 N4 structure with nitrogen defects (Pd/DCN) are synthesized. The resulting Pd/DCN exhibits excellent photocatalytic performance in the transfer hydrogenation of alkynes with ammonia borane. The reaction rate and selectivity of Pd/DCN are superior to those of Pd/BCN (bulk C3 N4 without nitrogen defects) under visible-light irradiation. The characterization results and density functional theory calculations show that the Mott-Schottky effect in Pd/DCN can change the electronic density of the Pd NPs, and thus enhances the hydrogenation selectivity toward phenylacetylene. After 1 h, the hydrogenation selectivity of Pd/DCN reaches 95%, surpassing that of Pd/BCN (83%). Meanwhile, nitrogen defects in the supports improve the visible-light response and accelerate the transfer and separation of photogenerated charges to enhance the catalytic activity of Pd/DCN. Therefore, Pd/DCN exhibits higher efficiency under visible light, with a turnover frequency (TOF) of 2002 min-1 . This TOF is five times that of Pd/DCN under dark conditions and 1.5 times that of Pd/BCN. This study provides new insights into the rational design of high-performance photocatalytic transfer hydrogenation catalysts.

16.
J Colloid Interface Sci ; 650(Pt A): 193-202, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37402325

RESUMEN

Solar-driven electrochemical NO3- reduction reaction (NO3-RR) is a clean and sustainable strategy that can convert pollutant NO3- in wastewater to value-added NH3. In recent years, cobalt oxides-based catalysts have shown their intrinsic catalytic properties toward NO3-RR but still have room for improvement through catalyst design. Coupling metal oxides with noble metal has been demonstrated to improve electrochemical catalytic efficiency. Here, we use Au species to tune the surface structure of Co3O4 and improve the efficiency of NO3-RR to NH3. The obtained Au nanocrystals-Co3O4 catalyst exhibited an onset potential of 0.54 V vs RHE, NH3 yield rate of 27.86 µg/h·cm2, and Faradaic efficiency (FE) of 83.1% at 0.437 V vs RHE in an H-cell, which is much higher than Au small species (Au clusters or single atoms)-Co3O4 (15.12 µg/h·cm2) and pure Co3O4 (11.38 µg/h·cm2), respectively. Combined experiments with theory calculations, we attributed the enhanced performance of Au nanocrystals-Co3O4 to the reduced energy barrier of *NO hydrogenation to the *NHO and suppression of HER, which originated from the charge transfer from Au to Co3O4. Using an amorphous silicon triple-junction (a-Si TJ) as the solar cell and an anion exchange membrane electrolyzer (AME), an unassisted solar-driven NO3-RR to NH3 prototype was realized with a yield rate of 4.65 mg/h and FE of 92.1%.

17.
J Am Chem Soc ; 145(29): 16218-16227, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37438261

RESUMEN

Recycling waste plastics requires the degradation of plastics into small molecules. However, various products are widely distributed using traditional methods of depolymerizing polystyrene (PS) such as catalytic pyrolysis and hydrogenolysis. Here, we creatively report a N-bridged Co, Ni dual-atom (Co-N-Ni) catalyst for the targeted conversion of waste PS plastics to ethylbenzene via a pressurized tandem fixed-bed reactor where hydropyrolysis is coupled with downstream vapor-phase hydrotreatment. The Co-N-Ni catalyst achieves 95 wt % PS conversion with 92 wt % ethylbenzene yield, significantly superior to the corresponding single-atom catalysts, and enables degradation of real PS plastics. Theoretical calculations and experimental results demonstrate that the d-band center of metal atoms is well regulated in the Co-N-Ni catalyst. The Co site activates the C═C bond more easily, while the Ni site spatially optimizes the adsorption configuration of the styrene molecule due to the electronic interaction. This Co-N-Ni catalyst in the tandem reactor also shows excellent durability and provides a new direction for real plastic degradation.

18.
Angew Chem Int Ed Engl ; 62(27): e202304183, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37154674

RESUMEN

Modulation of the ligands and coordination environment of metal-organic frameworks (MOFs) has been an effective and relatively unexplored avenue for improving the anode performance of lithium-ion batteries (LIBs). In this study, three MOFs are synthesized, namely, M4 (o-TTFOB)(bpm)2 (H2 O)2 (where M is Mn, Zn, and Cd; o-H8 TTFOB is ortho-tetrathiafulvalene octabenzoate; and bpm is 2,2'-bipyrimidine), based on a new ligand o-H8 TTFOB with two adjacent carboxylates on one phenyl, which allows us to establish the impact of metal coordination on the performance of these MOFs as anode materials in LIBs. Mn-o-TTFOB and Zn-o-TTFOB, with two more uncoordinated oxygen atoms from o-TTFOB8- , show higher reversible specific capacities of 1249 mAh g-1 and 1288 mAh g-1 under 200 mA g-1 after full activation. In contrast, Cd-o-TTFOB shows a reversible capacity of 448 mAh g-1 under the same condition due to the lack of uncoordinated oxygen atoms. Crystal structure analysis, cyclic voltammetry measurements of the half-cell configurations, and density functional theory calculations have been performed to explain the lithium storage mechanism, diffusion kinetics, and structure-function relationship. This study demonstrates the advantages of MOFs with high designability in the fabrication of LIBs.

19.
Biosens Bioelectron ; 235: 115365, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37196434

RESUMEN

Surveillance of iodine intake is important because either inadequate or excessive amount of iodine may lead to thyroid malfunctions. Herein, we report a method for fast iodide quantification based on a plasmonic hot electron-driven chemical reaction, which occurs on Au@Ag core-shell nanoparticles (NPs) coated with p-nitrothiophenol (PNTP) molecules. Upon resonant light illumination, hot electron-hole pairs are generated in the NPs. The hot holes capture iodide ions (I-) and form AgI which decomposes under light; while the hot electrons are shifted to the electron orbital (LUMO) of PNTP and trigger its reduction to p-aminothiophenol (PATP). By measuring characteristic surface-enhanced Raman spectroscopic (SERS) peaks of PNTP and PATP, the concentration of I- in water can be quantitatively determined, with a linear response in the 0.5-20 µM range and a detection limit of 0.30 µM. The Au@Ag nanosensor was then applied for I- detection in various biofluids including urine, serum and saliva, exhibiting superior detection sensitivity and high selectivity. This sensing assay requires a small sample volume of ∼10 µL and completes the entire detection process in ∼2 min, and therefore holds significant potential for application in point-of-care settings.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Nanopartículas del Metal/química , Yoduros , Electrones , Oro/química , Plata/química , Anticuerpos
20.
Bioresour Technol ; 382: 129191, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37196742

RESUMEN

This work was developed to explore the versatility of thermophilic esterase for decolorizing raw molasses wastewater at high temperature and acidic pH. Combining covalent crosslinking method with deep eutectic solvent, a thermophilic esterase from Pyrobaculum calidifontis was immobilized on chitosan/macroporous resin composite carrier. The application of this immobilized thermophilic esterase eliminated 92.35% of colorants in raw molasses wastewater, achieving maximal decolorization efficiency across all the enzymes tested. Strikingly, this immobilized thermophilic esterase was capable of engaging in continuous activity for a 5-day period while removing 76.23% of pigments from samples. It effectively and continuously eliminated BOD5 and COD, effectively and directly facilitating raw molasses wastewater decolorization under extreme conditions more readily than control group. In addition, this thermophilic esterase was believed to achieve decolorization through an addition reaction that disrupted conjugated system of melanoidins. Together, these results highlight an efficient and practical means of achieving enzyme-based molasses wastewater decolorization.


Asunto(s)
Melaza , Aguas Residuales , Esterasas , Polímeros
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