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1.
Nano Lett ; 24(19): 5920-5928, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38708934

RESUMO

A significant challenge in direct seawater electrolysis is the rapid deactivation of the cathode due to the large scaling of Mg(OH)2. Herein, we synthesized a Pt-coated highly disordered NiCu alloy (Pt-NiCu alloy) electrode with superior solidophobic behavior, enabling stable hydrogen generation (100 mA cm-2, >1000 h durability) and simultaneous production of Mg(OH)2 (>99.0% purity) in electrolyte enriched with Mg2+ and Ca2+. The unconventional solidophobic property primarily stems from the high surface energy of the NiCu alloy substrate, which facilitates the adsorption of surface water and thereby compels the bulk formation of Mg(OH)2 via homogeneous nucleation. The discovery of this solidophobic electrode will revolutionarily simplify the existing techniques for seawater electrolysis and increase the economic viability for seawater electrolysis.

2.
Analyst ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721993

RESUMO

A novel analysis technique of elements at ambient conditions has been developed. The technique is based on microwave-assisted laser-induced breakdown spectroscopy (MW-LIBS) applied to acoustically levitated samples. The technique has been demonstrated using three solid samples with different properties and compositions. These are ore containing multiple elements (OREAS 520), aluminium oxide (Al3O2) and gypsum (CaSO4·2H2O). The mass of samples was 21 mg, 23 mg, and 55 mg for gypsum, mineral ore, and Al3O2, respectively. Significant signal enhancements were recorded for a variety of elements, using microwave-assisted laser-induced breakdown spectroscopy and levitation (MW-LIBS-Levitation). The signal enhancement for Mn I (403.07 nm), Al I (396.13 nm) and Ca II (393.85 nm) was determined as 123, 46, and 63 times, respectively. Moreover, it was found that MW-LIBS-Levitation minimises the self-absorption of the Ca I (422.67 nm) and Na I (588.99 nm and 589.59 nm) spectral lines. In addition to the signal enhancements, the levitation process produces a spinning motion in the solids with an angular frequency of 7 Hz. This feature benefits laser-based analysis as a fresh sample is introduced at each laser pulse, eliminating the need for the usual mechanical devices. Based on the single-shot analysis, it was found that ∼80% of the laser pulses produced successful MW-LIBS-Levitation detection, confirming an impressive repeatability of the process. This contactless analytical technique can be applied in ambient pressure and temperature conditions with high sensitivity, which can benefit disciplines such as forensics science, isotope analysis, and medical analysis, where the sample availability is often diminutive.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38693896

RESUMO

Metal/metal oxide clusters possess a higher count of unsaturated coordination sites than nanoparticles, providing multiatomic sites that single atoms do not. Encapsulating metal/metal oxide clusters within zeolites is a promising approach for synthesizing and stabilizing these clusters. The unique feature endows the metal clusters with an exceptional catalytic performance in a broad range of catalytic reactions. However, the encapsulation of stable FeOx clusters in zeolite is still challenging, which limits the application of zeolite-encapsulated FeOx clusters in catalysis. Herein, we design a modified solvent-free method to encapsulate FeOx clusters in pure siliceous MFI zeolites (Fe@MFI). It is revealed that the 0.3-0.4 nm subnanometric FeOx clusters are stably encapsulated in the 5/6-membered rings intersectional voids of the pure siliceous MFI zeolites. The encapsulated Fe@MFI catalyst with a Fe loading of 1.4 wt % demonstrates remarkable catalytic activity and recycle stability in the direct oxidation of methane, while also promoting the direct oxidation of cyclohexane, surpassing the performance of conventional zeolite-supported Fe catalysts.

4.
Small ; : e2401798, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700074

RESUMO

The covalent organic frameworks (COFs) possessing high crystallinity and capability to capture low-concentration CO2 (400 ppm) from air are still underdeveloped. The challenge lies in simultaneously incorporating high-density active sites for CO2 insertion and maintaining the ordered structure. Herein, a structure engineering approach is developed to afford an ionic pair-functionalized crystalline and stable fluorinated COF (F-COF) skeleton. The ordered structure of the F-COF is well maintained after the integration of abundant basic fluorinated alcoholate anions, as revealed by synchrotron X-ray scattering experiments. The breakthrough test demonstrates its attractive performance in capturing (400 ppm) CO2 from gas mixtures via O─C bond formation, as indicated by the in situ spectroscopy and operando nuclear magnetic resonance spectroscopy using 13C-labeled CO2 sources. Both theoretical and experimental thermodynamic studies reveal the reaction enthalpy of ≈-40 kJ mol-1 between CO2 and the COF scaffolds. This implies weaker interaction strength compared with state-of-the-art amine-derived sorbents, thus allowing complete CO2 release with less energy input. The structure evolution study from synchrotron X-ray scattering and small-angle neutron scattering confirms the well-maintained crystalline patterns after CO2 insertion. The as-developed proof-of-concept approach provides guidance on anchoring binding sites for direct air capture (DAC) of CO2 in crystalline scaffolds.

6.
Materials (Basel) ; 17(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38612212

RESUMO

A series of Ti41Zr25Be34-xNix (x = 4, 6, 8, 10 at.%) and Ti41Zr25Be34-xCux (x = 4, 6, 8 at.%) bulk metallic glasses were investigated to examine the influence of Ni and Cu content on the viscosity, thermoplastic formability, and nanoindentation of Ti-based bulk metallic glasses. The results demonstrate that Ti41Zr25Be30Ni4 and Ti41Zr25Be26Cu8 amorphous alloys have superior thermoplastic formability among the Ti41Zr25Be34-xNix and Ti41Zr25Be34-xCux amorphous alloys due to their low viscosity in the supercooled liquid region and wider supercooled liquid region. The hardness and modulus exhibit obvious variations with increasing Ni and Cu content in Ti-based bulk metallic glasses, which can be attributed to alterations in atomic density. Optimal amounts of Ni and Cu in Ti-based bulk metallic glasses enhance thermoplastic formability and mechanical properties. The influence of Ni and Cu content on the hardness of Ti-based bulk metallic glasses is discussed from the perspective of the mean atomic distance.

7.
J Am Chem Soc ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683738

RESUMO

Palladium hydrides (PdHx) are pivotal in both fundamental research and practical applications across a wide spectrum. PdHx nanocrystals, synthesized by heating in dimethylformamide (DMF), exhibit remarkable stability, granting them widespread applications in the field of electrocatalysis. However, this stability appears inconsistent with their metastable nature. The substantial challenges in characterizing nanoscale structures contribute to the limited understanding of this anomalous phenomenon. Here, through a series of well-conceived experimental designs and advanced characterization techniques, including aberration-corrected scanning transmission electron microscopy (AC-STEM), in situ X-ray diffraction (XRD), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), we have uncovered evidence that indicates the presence of C and N within the lattice of Pd (PdCxNy), rather than H (PdHx). By combining theoretical calculations, we have thoroughly studied the potential configurations and thermodynamic stability of PdCxNy, demonstrating a 2.5:1 ratio of C to N infiltration into the Pd lattice. Furthermore, we successfully modulated the electronic structure of Pd nanocrystals through C and N doping, enhancing their catalytic activity in methanol oxidation reactions. This breakthrough provides a new perspective on the structure and composition of Pd-based nanocrystals infused with light elements, paving the way for the development of advanced catalytic materials in the future.

8.
J Phys Chem B ; 128(16): 3972-3980, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38624173

RESUMO

Complex molten chloride salt mixtures of uranium, magnesium, and sodium are top candidates for promising nuclear energy technologies to produce electricity based on molten salt reactors. From a local structural perspective, LaCl3 is similar to UCl3 and hence a good proxy to study these complex salt mixtures. As fission products, lanthanide salts and their mixtures are also very important in their own right. This article describes from an experimental and theory perspective how very different the structural roles of MgCl2 and NaCl are in mixtures with LaCl3. We find that, whereas MgCl2 becomes an integral part of multivalent ionic networks, NaCl separates them. In a recent article (J. Am. Chem. Soc. 2022, 144, 21751-21762) we have called the disruptive behavior of NaCl "the spacer salt effect". Because of the heterogeneous nature of these salt mixtures, there are multiple structural motifs in the melt, each with its particular free energetics. Our work identifies and quantifies these; it also elucidates the mechanisms through which Cl- ions exchange between Mg2+-rich and La3+-rich environments.

9.
Ind Eng Chem Res ; 63(13): 5871-5879, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38586216

RESUMO

Dilute concentration (∼400 ppm) and humidity are two important factors in the direct air capture (DAC) of CO2 by supported sorbents. In this work, a minimal DAC CO2 adsorption-kinetics model was formulated for supported amine sorbents under dry and humid conditions. Our model fits well with a recent DAC experiment with supported amine sorbent in both dry and humid conditions. Temperature and flow rate effects on breakthrough curves were quantitatively captured, and increasing temperature led to faster CO2 adsorption kinetics. Moisture was shown to broaden the breakthrough curve with slower CO2 adsorption kinetics but significantly improve the uptake capacity. The present minimal model provides a versatile platform for kinetic modeling of the DAC of CO2 on supported amine and other chemisorption systems.

10.
Nano Lett ; 24(18): 5444-5452, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639448

RESUMO

We report, for the first time, a new synthetic strategy for the preparation of crystalline two-dimensional olefin-linked covalent organic frameworks (COFs) based on aldol condensation between benzodifurandione and aromatic aldehydes. Olefin-linked COFs can be facilely crystallized through either a pyridine-promoted solvothermal process or a benzoic anhydride-mediated organic flux synthesis. The resultant COF leaf with high in-plane π-conjugation exhibits efficient visible-light-driven photoreduction of carbon dioxide (CO2) with water (H2O) in the absence of any photosensitizer, sacrificial agents, or cocatalysts. The production rate of carbon monoxide (CO) reaches as high as 158.1 µmol g-1 h-1 with near 100% CO selectivity, which is accompanied by the oxidation of H2O to oxygen. Both theoretical and experimental results confirm that the key lies in achieving exceptional photoinduced charge separation and low exciton binding. We anticipate that our findings will facilitate new possibilities for the development of semiconducting COFs with structural diversity and functional variability.

11.
Adv Mater ; : e2313853, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684169

RESUMO

Organic acid-based deep eutectic solvents (DESs) as catalysts always suffer from weak stability and low recyclability due to the accumulation of organic oxidative products in the DES phase. Herein, a completely inorganic deep eutectic solvent (IDES) ZnCl2/PA with zinc chloride (ZnCl2) and phosphoric acid (PA) as precursors is constructed to realize liquid-liquid interface catalysis for desulfurization of fuel and product self-separation for the first time. Owing to the inorganic nature, the organic oxidative products are accumulated at the interface between the IDES and fuel rather than the IDES phase. With this unique feature, the IDES can be reused for at least 15 times without any further treatment in oxidative desulfurization process, showing a state-of-the-art cycle-regeneration stability. Moreover, compared with the reported organic DESs, the IDES also reveals more attractive catalytic oxidative desulfurization performance. Experimental and theoretical studies indicate that the strong coordination Zn···O═P and the strong adsorption energy between IDES and sulfides enhance the activation of H2O2 to reactive oxygen species, leading to the superior catalytic performance in oxidative desulfurization of fuel.

12.
Skeletal Radiol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512364

RESUMO

A 50-year-old male presented with neck and shoulder pain. Chest CT and 18F-FDG PET/CT revealed osteolytic bone destruction in the left first rib and thoracic vertebrae with increased FDG uptake. Rib biopsy pathology indicated desmoplastic small round cell tumor (DSRCT).18F-FDG PET/CT can accurately locate the distribution of DSRCT and further guide the location of needle biopsy to assist the DSRCT.

13.
J Cell Mol Med ; 28(7): e18173, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494841

RESUMO

Osteoarthritis (OA) is a chronic degenerative joint disease that affects worldwide. Oxidative stress plays a critical role in the chronic inflammation and OA progression. Scavenging overproduced reactive oxygen species (ROS) could be rational strategy for OA treatment. Bilirubin (BR) is a potent endogenous antioxidant that can scavenge various ROS and also exhibit anti-inflammatory effects. However, whether BR could exert protection on chondrocytes for OA treatment has not yet been elucidated. Here, chondrocytes were exposed to hydrogen peroxide with or without BR treatment. The cell viability was assessed, and the intracellular ROS, inflammation cytokines were monitored to indicate the state of chondrocytes. In addition, BR was also tested on LPS-treated Raw264.7 cells to test the anti-inflammation property. An in vitro bimimic OA microenvironment was constructed by LPS-treated Raw264.7 and chondrocytes, and BR also exert certain protection for chondrocytes by activating Nrf2/HO-1 pathway and suppressing NF-κB signalling. An ACLT-induced OA model was constructed to test the in vivo therapeutic efficacy of BR. Compared to the clinical used HA, BR significantly reduced cartilage degeneration and delayed OA progression. Overall, our data shows that BR has a protective effect on chondrocytes and can delay OA progression caused by oxidative stress.


Assuntos
NF-kappa B , Osteoartrite , Humanos , NF-kappa B/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Bilirrubina/farmacologia , Lipopolissacarídeos/farmacologia , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Inflamação/tratamento farmacológico , Condrócitos/metabolismo , Interleucina-1beta/farmacologia
14.
Biochim Biophys Acta Rev Cancer ; 1879(3): 189096, 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38499079

RESUMO

Colorectal cancer (CRC) is one of the deadliest malignancies worldwide, ranking third in incidence and second in mortality. Remarkably, early stage localized CRC has a 5-year survival rate of over 90%; in stark contrast, the corresponding 5-year survival rate for metastatic CRC (mCRC) is only 14%. Compounding this problem is the staggering lack of effective therapeutic strategies. Beyond genetic mutations, which have been identified as critical instigators of CRC initiation and progression, the importance of epigenetic modifications, particularly DNA methylation (DNAm), cannot be underestimated, given that DNAm can be used for diagnosis, treatment monitoring and prognostic evaluation. This review addresses the intricate mechanisms governing aberrant DNAm in CRC and its profound impact on critical oncogenic pathways. In addition, a comprehensive review of the various techniques used to detect DNAm alterations in CRC is provided, along with an exploration of the clinical utility of cancer-specific DNAm alterations.

15.
Nat Commun ; 15(1): 2390, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493199

RESUMO

Metal-halide perovskite thin monocrystals featuring efficient carrier collection and transport capabilities are well suited for radiation detectors, yet their growth in a generic, well-controlled manner remains challenging. Here, we reveal that mass transfer is one major limiting factor during solution growth of perovskite thin monocrystals. A general approach is developed to overcome synthetic limitation by using a high solute flux system, in which mass diffusion coefficient is improved from 1.7×10-10 to 5.4×10-10 m2 s-1 by suppressing monomer aggregation. The generality of this approach is validated by the synthesis of 29 types of perovskite thin monocrystals at 40-90 °C with the growth velocity up to 27.2 µm min-1. The as-grown perovskite monocrystals deliver a high X-ray sensitivity of 1.74×105 µC Gy-1 cm-2 without applied bias. The findings regarding limited mass transfer and high-flux crystallization are crucial towards advancing the preparation and application of perovskite thin monocrystals.

16.
J Autoimmun ; 145: 103202, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493674

RESUMO

OBJECTIVES: To provide a comprehensive analysis and modelling of the global epidemiology of psoriatic arthritis (PsA) in patients with psoriasis. METHODS: We reviewed and analysed PsA epidemiology studies over the past 45 years. A Bayesian hierarchical linear mixed model was developed to provide comprehensive age- and sex-specific epidemiologic estimates in different countries and regions. RESULTS: Three hundred and sixty-three studies were systematically reviewed. The incidence of PsA in patients with psoriasis varied from 2.31 per 1000 person-years in the United Kingdom to 74.00 per 1000 person-years in several Western European countries. The global prevalence of PsA in patients with psoriasis is estimated to be 17.58% (3.33%, 43.69%). Regionally, the overall prevalence of PsA in patients with psoriasis varies from 7.62% (4.18%, 12.28%) in Australasia to 26.59% (18.89%, 35.76%) in North America. The Caribbean and Central Latin America also have relatively high prevalence and are estimated at 23.14% (14.06%, 35.17%) and 22.81% (14.36%, 32.25%), respectively. The prevalence of PsA is higher in adults than children (23.93% vs 8.59%) and also slightly higher in females than males (19.14% vs 16.01%). CONCLUSIONS: This study provides valuable insights into the global epidemiology of PsA. It also serves as a useful resource for researchers in areas lacking relevant studies. These findings have important implications for clinicians managing the course of PsA and for health policymakers in resource allocation.


Assuntos
Artrite Psoriásica , Psoríase , Humanos , Artrite Psoriásica/epidemiologia , Prevalência , Psoríase/epidemiologia , Incidência , Masculino , Feminino , Saúde Global , Teorema de Bayes
17.
Appl Environ Microbiol ; 90(3): e0207523, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38319096

RESUMO

Labyrinthulomycetes play an important role in marine biogeochemical cycles, but their diversity, distribution patterns, and key regulatory factors remain unclear. This study measured the abundance and diversity of Labyrinthulomycetes in the Pearl River Estuary (PRE) to understand its distribution pattern and relationship with environmental and biological factors. The abundance of Labyrinthulomycetes ranged from 24 to 500 cells·mL-1, with an average of 144.37 ± 94.65 cells·mL-1, and its community composition showed obvious ecological partitioning in the PRE. The results of statistical analysis indicated that CDOM, salinity, and chlorophyll a contributed significantly (P < 0.01) to the community composition, explaining 46.59%, 11.34%, and 4.38% of the variance, respectively. The Labyrinthulomycetes distribution pattern combined with the niches of dominant species was revealed; low-salinity species mainly use terrigenous organic matter occupied dominant positions in the upper estuary and showed the highest abundance; moderate-salinity species that can use phytoplankton-derived resources thrived in the middle estuary; and seawater species dominated the lower estuary with the highest diversity but the lowest abundance. In addition, the results of phylogenetic tree analysis indicated that the existence of a novel lineage, and further study on the diversity and ecological functions of Labyrinthulomycetes is needed.IMPORTANCELabyrinthulomycetes play important roles in organic matter remineralization, carbon sinks, and food webs. However, the true diversity of Labyrinthulomycetes is still unclear due to limitations in isolation and culture methods. In addition, previous studies on their relationship with environmental factors are inconsistent and even contradictory, and it is speculated that their community composition may have spatial heterogeneity along the environmental gradient. In this study, the distribution pattern and key regulators of Labyrinthulomycetes in the PRE were revealed. Combining the niche of dominant species, it is suggested that salinity determines the spatial differences in Labyrinthulomycetes diversity, and the resources of substrate (terrestrial input or phytoplankton-derived) determine the dominant species, and its abundance is mainly determined by organic matter concentrations. Our study provided new information on the Labyrinthulomycetes diversity and verified the spatial heterogeneity of Labyrinthulomycetes community composition, providing reliable explanations for the inconsistencies in previous studies.


Assuntos
Rios , Estramenópilas , Clorofila A , Estuários , Filogenia , Fitoplâncton
18.
J Am Chem Soc ; 146(10): 6618-6627, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349322

RESUMO

Single-crystal semiconductor-based photocatalysts exposing unique crystallographic facets show promising applications in energy and environmental technologies; however, crystal facet engineering through solid-state synthesis for photocatalytic overall water splitting is still challenging. Herein, we develop a novel crystal facet engineering strategy through solid-state recrystallization to synthesize uniform SrTiO3 single crystals exposing tailored {111} facets. The presynthesized low-crystalline SrTiO3 precursors enable the formation of well-defined single crystals through kinetically improved crystal structure transformation during solid-state recrystallization process. By employing subtle Al3+ ions as surface morphology modulators, the crystal surface orientation can be precisely tuned to a controlled percentage of {111} facets. The photocatalytic overall water splitting activity increases with the exposure percentage of {111} facets. Owing to the outstanding crystallinity and favorable anisotropic surface structure, the SrTiO3 single crystals with 36.6% of {111} facets lead to a 3-fold enhancement of photocatalytic hydrogen evolution rates up to 1.55 mmol·h-1 in a stoichiometric ratio of 2:1 than thermodynamically stable SrTiO3 enclosed with isotropic {100} facets.

19.
Int J Rheum Dis ; 27(2): e15098, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38402436
20.
J Am Chem Soc ; 146(8): 5693-5701, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38335459

RESUMO

Rationally modulating the binding strength of reaction intermediates on surface sites of copper-based catalysts could facilitate C-C coupling to generate multicarbon products in an electrochemical CO2 reduction reaction. Herein, theoretical calculations reveal that cascade Ag-Cu dual sites could synergistically increase local CO coverage and lower the kinetic barrier for CO protonation, leading to enhanced asymmetric C-C coupling to generate C2H4. As a proof of concept, the Cu3N-Ag nanocubes (NCs) with Ag located in partial Cu sites and a Cu3N unit center are successfully synthesized. The Faraday efficiency and partial current density of C2H4 over Cu3N-Ag NCs are 7.8 and 9.0 times those of Cu3N NCs, respectively. In situ spectroscopies combined with theoretical calculations confirm that Ag sites produce CO and Cu sites promote asymmetric C-C coupling to *COCHO, significantly enhancing the generation of C2H4. Our work provides new insights into the cascade catalysis strategy at the atomic scale for boosting CO2 to multicarbon products.

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