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1.
Nano Lett ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38781119

RESUMEN

Although transition-metal nitrides have been widely applied for several decades, experimental investigations of their high-resolution electronic band structures are rare due to the lack of high-quality single-crystalline samples. Here, we report on the first momentum-resolved electronic band structures of titanium nitride (TiN) films, which are remarkable nitride superconductors. The measurements of the crystal structures and electrical transport properties confirmed the high quality of these films. More importantly, from a combination of high-resolution angle-resolved photoelectron spectroscopy and first-principles calculations, the extracted Coulomb interaction strength of TiN films can be as large as 8.5 eV, whereas resonant photoemission spectroscopy yields a value of 6.26 eV. These large values of Coulomb interaction strength indicate that superconducting TiN is a strongly correlated system. Our results uncover the unexpected electronic correlations in transition-metal nitrides, potentially providing a perspective not only to understand their emergent quantum states but also to develop their applications in quantum devices.

2.
J Sep Sci ; 46(24): e2300531, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37933967

RESUMEN

Our previous studies confirmed the efficacy of gross saponins of Tribulus terrestris L. fruit in treating cerebral ischemia. This study aimed to investigate the related mechanisms in vitro. The lipopolysaccharide-induced BV2 cells model was constructed and treated with gross saponins at different concentrations to explore its anti-inflammatory activity. The cell metabolite changes were tracked by liquid chromatography-mass spectrometry (LC-MS)-based metabolomics, and the metabolic biomarkers and related metabolic pathways were analyzed. Molecular biochemistry analysis was further used to verify the relevant inflammatory pathways. The results showed that the saponins reduced nitric oxide release and the secretion of tumor necrosis factor-alpha, interleukin-1ß, and interleukin-6 from lipopolysaccharide-induced BV2 cells. Metabolic perturbations occurred in lipopolysaccharide-treated BV2 cells, which could be reversed by drug treatment via mainly regulating glycerophospholipid metabolism, tryptophan metabolism, purine metabolism pathways, etc. The western blot analysis demonstrated that saponin could suppress the activation of the inflammatory-related signaling pathway. The present study explored the in vitro anti-inflammatory mechanism of gross saponins of Tribulus terrestris L. fruit using an LC-MS-based cell metabolomics approach, which confirms the great potential of LC-MS for drug efficacy evaluation and can be applied in other herbal medicine-related analyses.


Asunto(s)
Saponinas , Tribulus , Saponinas/análisis , Frutas/química , Cromatografía Líquida con Espectrometría de Masas , Tribulus/química , Lipopolisacáridos/farmacología , Metabolómica , Antiinflamatorios/farmacología , Antiinflamatorios/análisis
3.
Appl Opt ; 61(24): 7033-7040, 2022 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-36256319

RESUMEN

In this paper, we design a free-form off-axis three-mirror optical system with a low f-number and compact structure, which can be used as an infrared reflection imager. The initial structure is calculated from the near-axis optical transfer matrix based on third-order aberration theory. Particular constraints are designed to install all mirrors on the same substrate for simultaneous milling, which reduces the processing difficulty and effectively avoids errors caused by component assembly. Zernike free-form surfaces are introduced to correct aberrations. This optical system has a field of view of 5∘×5∘ and an f-number of 1.82; the modulation transfer function of the system is higher than 0.6 at 30 lp/mm. The results of the tolerance assignment of the system were verified by the Monte Carlo method, and the machining tolerance is reasonable and easy to achieve. This design not only improves the optical performance of the system but also enhances the feasibility of manufacturing.

4.
Appl Opt ; 60(32): 10132-10139, 2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34807120

RESUMEN

In order to improve the performance and simplify the structure of an optical antenna for a space laser communication system, we design a free-form off-axis three-mirror optical antenna with an integrated primary/tertiary-mirror structure. The adoption of the integrated primary/tertiary-mirror structure improves efficiency of light energy utilization and reduces the complexity of optical processing and assembly. The introduction of free-form optical elements and optical structure constraints helps to correct the off-axis aberration and realize a large field of view. The obtained optical antenna has the magnification of five times and field of view of 2.4∘×2.4∘. The image quality obtained here reaches the diffraction-limited level. At the communication wavelength of 808 nm, the wavefront error is better than λ/22, and the system has a high energy concentration. The proposed optical antenna could not only improve tracking accuracy of the optical antenna in space but also greatly reduce the complexity of the laser communication system. It has reference significance and application value for free-space laser communication.

5.
J Ethnopharmacol ; 322: 117650, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38135230

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Shegan Mahuang Decoction (SMD) is a classic traditional Chinese medicine (TCM) formula for asthma treatment, but the anti-asthma mechanism of SMD is still not fully studied. AIMS OF THE STUDY: In this study, we established an ovalbumin (OVA)-induced asthma rat model and treated it with SMD to observe its anti-asthma effect and explore the related mechanism. MATERIALS AND METHODS: We evaluated the anti-inflammatory effect of SMD via testing the levels of immunoglobulin E (IgE), C-reactive protein (CRP), interleukin-4 (IL-4), interleukin-6 (IL-6) in serum and performing the hematoxylin-eosin (H&E) staining of lung tissue slices. We analyzed the variations of metabolites and proteins in the lung tissue of different groups using liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics and TMT-based proteomics approaches. The metabolic biomarkers and differentially expressed proteins (DEPs) were picked, and the related signal transduction pathways were also investigated. In addition, the key proteins on the signaling pathway were validated through western blotting (WB) experiment to reveal the anti-asthma mechanism of SMD. RESULTS: The results showed that the SMD could significantly reduce the serum levels of IgE, CRP, IL-4, and IL-6 and attenuate the OVA-induced pathological changes in lung tissue. A total of 34 metabolic biomarkers and 84 DEPs were screened from rat lung tissue, which were mainly associated with lipid metabolism, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, the excessive production of reactive oxygen species (ROS), and lysosome pathway. Besides, SMD could inhibit the myeloid differentiation factor 88 (MyD88)/inhibitor of kappa B kinase (IKK)/nuclear factor-kappa B (NF-κB) signaling pathway to exhibit anti-inflammatory activities. CONCLUSIONS: SMD exhibited a therapeutic effect on asthma, which possibly be exerted by inhibiting the MyD88/IKK/NF-κB signaling pathway.


Asunto(s)
Antiasmáticos , Asma , Medicamentos Herbarios Chinos , Ratas , Animales , Proteoma , Interleucina-4/metabolismo , FN-kappa B/metabolismo , Interleucina-6/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , Multiómica , Asma/inducido químicamente , Asma/tratamiento farmacológico , Asma/metabolismo , Pulmón , Antiasmáticos/farmacología , Antiasmáticos/uso terapéutico , Antiinflamatorios/farmacología , Metaboloma , Biomarcadores/metabolismo , Inmunoglobulina E , Ovalbúmina/farmacología
6.
Adv Sci (Weinh) ; 11(2): e2304146, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38010981

RESUMEN

Conversion-type electrodes offer a promising multielectron transfer alternative to intercalation hosts with potentially high-capacity release in batteries. However, the poor cycle stability severely hinders their application, especially in aqueous multivalence-ion systems, which can fundamentally impute to anisotropic ion diffusion channel collapse in pristine crystals and irreversible bond fracture during repeated conversion. Here, an amorphous bismuth sulfide (a-BS) formed in situ with unprecedentedly self-controlled moderate conversion Cu2+ storage is proposed to comprehensively regulate the isotropic ion diffusion channels and highly reversible bond evolution. Operando synchrotron X-ray diffraction and substantive verification tests reveal that the total destruction of the Bi─S bond and unsustainable deep alloying are fully restrained. The amorphous structure with robust ion diffusion channels, unique self-controlled moderate conversion, and high electrical conductivity discharge products synergistically boosts the capacity (326.7 mAh g-1 at 1 A g-1 ), rate performance (194.5 mAh g-1 at 10 A g-1 ), and long-lifespan stability (over 8000 cycles with a decay rate of only 0.02 ‰ per cycle). Moreover, the a-BS Cu2+ ‖Zn2+ hybrid ion battery can well supply a stable energy density of 238.6 Wh kg-1 at 9760 W kg-1 . The intrinsically high-stability conversion mechanism explored on amorphous electrodes provides a new opportunity for advanced aqueous storage.

7.
Adv Mater ; 35(48): e2305087, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37572369

RESUMEN

High-energy metal anodes for large-scale reversible batteries with inexpensive and nonflammable aqueous electrolytes promise the capability of supporting higher current density, satisfactory lifetime, nontoxicity, and low-cost commercial manufacturing, yet remain out of reach due to the lack of reliable electrode-electrolyte interphase engineering. Herein, in situ formed robust interphase on copper metal electrodes (CMEs) induced by a trace amount of potassium dihydrogen phosphate (0.05 m in 1 m CuSO4 -H2 O electrolyte) to fulfill all aforementioned requirements is demonstrated. Impressively, an unprecedented ultrahigh-speed copper plating/stripping capability is achieved at 100 mA cm-2  for over 12 000 cycles, corresponding to an accumulative areal capacity up to tens of times higher than previously reported CMEs. The use of solid-electrolyte interface-protection strategy brings at least an order of magnitude improvement in cycling stability for symmetric cells (Cu||Cu, 2800 h) and full batteries with CMEs using either sulfur cathodes (S||Cu, 1000 cycles without capacity decay) or zinc anodes (Cu||Zn with all-metal electrodes, discharge voltage ≈1.02 V). The comprehensive analysis reveals that the hydrophilic phosphate-rich interphase nanostructures homogenize copper-ion deposition and suppress nucleation overpotential, enabling dendrite-free CMEs with sustainability and ability to tolerate unusual-high power densities. The findings represent an elegant forerunner toward the promising goal of metal electrode applications.

8.
ACS Nano ; 17(19): 19144-19154, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37772918

RESUMEN

Electronic structure defines the conductivity and ion absorption characteristics of a functional electrode, significantly affecting the charge transfer capability in batteries, while it is rarely thought to be involved in mesoscopic volume and diffusion kinetics of the host lattice for promoting ion storage. Here, we first correlate the evolution in electronic structure of the Mo6S8 cathode with the ability to bound volume expansion and accelerate diffusion kinetics for high-performance aqueous Cu2+ storage. Operando synchrotron energy-dispersive X-ray absorption spectroscopy reveals that accumulative delocalized Mo 4d electrons enhance the Mo-Mo interaction with distinctly contracting and uniformizing Mo6 clusters during the reduction of Mo6S8, which potently restrain lattice expansion and release space to promote Cu2+ diffusion kinetics. Operando synchrotron X-ray diffraction and comprehensive characterizations further validate the structural and electrochemical properties induced by the Cu2+ intercalation electronic structure, endowing the Mo6S8 cathode a high specific capacity with small volume expansion, fast ions diffusion, and long-term cycling stability.

9.
Adv Mater ; 35(9): e2209322, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36482793

RESUMEN

Pursuing conversion-type cathodes with high volumetric capacity that can be used in aqueous environments remains rewarding and challenging. Tellurium (Te) is a promising alternative electrode due to its intrinsic attractive electronic conductivity and high theoretical volumetric capacity yet still to be explored. Herein, the kinetically/thermodynamically co-dominat copper-tellurium (Cu-Te) alloying phase-conversion process and corresponding oxidation failure mechanism of tellurium are investigated using in situ synchrotron X-ray diffraction and comprehensive ex situ characterization techniques. By virtue of the fundamental insights into the tellurium electrode, facile and precise electrolyte engineering (solvated structure modulation or reductive antioxidant addition) is implemented to essentially tackle the dramatic capacity loss in tellurium, affording reversible aqueous Cu-Te conversion reaction with an unprecedented ultrahigh volumetric capacity of up to 3927 mAh cm-3 , a flat long discharge plateau (capacity proportion of ≈81%), and an extraordinary level of capacity retention of 80.4% over 2000 cycles at 20 A g-1 of which lifespan thousand-fold longer than Cu-Te conversion using CuSO4 -H2 O electrolyte. This work paves a significant avenue for expanding high-performance conversion-type cathodes toward energetic aqueous multivalent-ion batteries.

10.
Adv Mater ; 35(52): e2306810, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37722006

RESUMEN

Titanium selenide (TiSe2 ), a model transition metal chalcogenide material, typically relies on topotactic ion intercalation/deintercalation to achieve stable ion storage with minimal disruption of the transport pathways but has restricted capacity (<130 mAh g-1 ). Developing novel energy storage mechanisms beyond conventional intercalation to break capacity limits in TiSe2 cathodes is essential yet challenging. Herein, the ion storage properties of TiSe2 are revisited and an unusual thermodynamically stable twin topotactic/nontopotactic Cu2+ accommodation mechanism for aqueous batteries is unraveled. In situ synchrotron X-ray diffraction and ex situ microscopy jointly demonstrated that topotactic intercalation sustained the ion transport framework, nontopotactic conversion involved localized multielectron reactions, and these two parallel reactions are miraculously intertwined in nanoscale space. Comprehensive experimental and theoretical results suggested that the twin-reaction mechanism significantly improved the electron transfer ability, and the reserved intercalated TiSe2 structure anchored the reduced titanium monomers with high affinity and promoted efficient charge transfer to synergistically enhance the capacity and reversibility. Consequently, TiSe2 nanoflake cathodes delivered a never-before-achieved capacity of 275.9 mAh g-1 at 0.1 A g-1 , 93.5% capacity retention over 1000 cycles, and endow hybrid batteries (TiSe2 -Cu||Zn) with a stable energy supply of 181.34 Wh kg-1 at 2339.81 W kg-1 , offering a promising model for aqueous ion storage.

11.
ACS Nano ; 17(7): 6497-6506, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36975102

RESUMEN

Exploring stable and durable cathodes for cost-effective reversible aqueous batteries is highly desirable for grid-scale energy storage applications, but significant challenges remain. Herein, we disclosed an ultrastable Cu2+ intercalation chemistry in mass-produced exfoliated NbS2 nanosheets to build ultralong lifespan aqueous batteries with cost advantages. Anisotropic interplanar expansion of NbS2 lattices balanced dynamic Cu2+ incorporation and the highly reversible redox reaction of Nb4+/Nb(4-δ)+ couple were illuminated by operando synchrotron X-ray diffraction and energy dispersive X-ray absorption spectroscopy, affording an extraordinary capacity of approximately 317 mAh g-1 at 1 A g-1 and a good stability of 92.2% capacity retention after 40000 cycles at 10 A g-1. Impressively, a budget NbS2||Fe hybrid ion cell involving an aqueous electrolyte/Fe-metal anode is established and provides a reliable energy supply of 225.4 Wh kg-1 at 750 W kg-1, providing insights for building advanced aqueous battery systems for large-scale applications.

12.
ACS Nano ; 16(8): 12095-12106, 2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-35912958

RESUMEN

Engineering multifunctional superstructure cathodes to conquer the critical issue of sluggish kinetics and large volume changes associated with divalent Zn-ion intercalation reactions is highly desirable for boosting practical Zn-ion battery applications. Herein, it is demonstrated that a MoS2/C19H42N+ (CTAB) superstructure can be rationally designed as a stable and high-rate cathode. Incorporation of soft organic CTAB into a rigid MoS2 host forming the superlattice structure not only effectively initiates and smooths Zn2+ transport paths by significantly expanding the MoS2 interlayer spacing (1.0 nm) but also endows structural stability to accommodate Zn2+ storage with expansion along the MoS2 in-plane, while synchronous shrinkage along the superlattice interlayer achieves volume self-regulation of the whole cathode, as evidenced by in situ synchrotron X-ray diffraction and substantial ex situ characterizations. Consequently, the optimized superlattice cathode delivers high-rate performance, long-term cycling stability (∼92.8% capacity retention at 10 A g-1 after 2100 cycles), and favorable flexibility in a pouch cell. Moreover, a decent areal capacity (0.87 mAh cm-2) is achieved even after a 10-fold increase of loading mass (∼11.5 mg cm-2), which is of great significance for practical applications. This work highlights the design of multifunctional superlattice electrodes for high-performance aqueous batteries.

13.
ACS Nano ; 15(9): 14766-14775, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34432437

RESUMEN

Aqueous zinc batteries (AZBs) are considered promising candidates for large-scale energy storage systems because of their low cost and high safety. However, currently developed AZB cathodes always suffer from the intense charge repulsion of multivalent-ion and complex multiphase electrochemistry, resulting in an insufficient cycling life and impracticable high-sloping discharge profile. Herein, we found that the synthesized ultrathin Bi2O2Se nanosheets can effectively activate stable protons storage in AZBs rather than large zinc ions. This proton-dominated cathode provides an ultraflat discharge plateau (72% capacity proportion) and exhibits long-term cyclability as 90.64% capacity retention after 2300 cycles at 1 A g-1. Further in situ synchrotron X-ray diffraction, ex situ X-ray photoelectronic spectroscopy, and density functional theory confirm the energy storage mechanism regarding the highly reversible proton insertion/extraction process. Benefiting from the proton-dominated fast dynamics, reliable energy supply (>81.5% discharge plateau capacity proportion) is demonstrated at a high rate of up to 10 A g-1 and in the frozen electrolyte below -15 °C. This work provides a potential design of high-performance electrode materials for AZBs.

14.
Chem Commun (Camb) ; 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22618488

RESUMEN

Isolated lithium sites were anchored on mesoporous silica by a molecular precursor approach at room temperature. The resultant materials exhibit ordered mesostructure, high base strength, and more importantly, a molecular-level dispersion of active sites, which are extremely desirable for catalysis and impossible to be realized by conventional methods.

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