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1.
Nano Lett ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311392

RESUMEN

S-redox involving solvated polysulfides is accompanied by volumetric change and structural decay of the S-based cathodes. Here, we propose a synchronous construction strategy for consolidating Li, Se, S, and C elements within a composite cathode via a paradigm reaction of 8Li+2Se+CS2 = 2Li4SeS+C. The obtained composite features crystalline Li4SeS encapsulated in a carbon nanocage (Li4SeS@C), exhibiting ultrahigh electrical conductivity, ultralow activation barrier, and excellent structural integrity, accordingly enabling large specific capacity (615 mAh g-1) and high capacity retention (87.3% after 350 cycles) at 10 A g-1. TOF-SIMS demonstrates its superior volumetric efficiency to a similar derivative SeS@C (2Se+CS2 = 2SeS+C), and DFT reveals its lower activation barrier than Li2S@C and Li2Se@C. This consolidation design significantly improves the electrochemical performance of S-based cathodes, and the paradigm reaction guarantees structural diversity and flexibility. Moreover, employing a synchronous construction mechanism to maximize the synergistic effect between element consolidation and carbon encapsulation opens up a new approach for developing robust S or chalcogenide cathodes.

2.
Small ; : e2406448, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39279302

RESUMEN

Designing nano-electrocatalysts rich in surface defects is critical to improve their catalytic performance. However, prevailing synthesis techniques rely heavily on complex procedures that compromise defect extensiveness and uniformity, casting a high demand for methods capable of synthesizing large-scale crystalline defects. An innovative design strategy is herein proposed that induces ample strain/dislocation defects during the growth of palladium (Pd), which is well-known as a good oxygen reduction reaction (ORR) catalyst. The controlled defect engineering on Pd core is achieved by the tensile stress exerted from an intentionally applied Fe3O4 skin layer during synthesis, which changes the surface free energy of Pd to stabilize the defect presence. With such large-scale crystalline defects, this Pd catalyst exhibits significantly higher ORR activity than commercial Pt/C, enabling its promising future in zinc-air battery catalysis. Additionally, the protective Fe3O4 skin covering the catalyst also enhances its catalytic stability. Theoretical calculations show that the superior catalytic property of such defect-engineered Pd is associated with the correspondingly modified adsorption energy of *O intermediates onto its surface, which further improves the reaction rate and thus boosts ORR kinetics. Findings here are expected to provide a paradigm for designing efficient and stable metal catalysts with plentiful large-scale strain defects.

3.
Small ; : e2401159, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716681

RESUMEN

Defects can introduce atomic structural modulation and tailor performance of materials. Herein, it demonstrates that semiconductor WO3 with inert electrocatalytic behavior can be activated through defect-induced tensile strains. Structural characterizations reveal that when simply treated in Ar/H2 atmosphere, oxygen vacancies will generate in WO3 and cause defective structures. Stacking faults are found in defects, thus modulating electronic structure and transforming electrocatalytic-inert WO3 into highly active electrocatalysts. Density functional theory (DFT) calculations are performed to calculate *H adsorption energies on various WOx surfaces, revealing the oxygen vacancy composition and strain predicted to optimize the catalytic activity of hydrogen evolution reaction (HER). Such defective tungsten oxides can be integrated into commercial proton exchange membrane (PEM) electrolyser with comparable performance toward Pt-based PEM. This work demonstrates defective metal oxides as promising non-noble metal catalysts for commercial PEM green-hydrogen generation.

4.
J Virol ; 97(5): e0058023, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37166302

RESUMEN

Hepatitis B virus (HBV) infection affects hepatic metabolism. Serum metabolomics studies have suggested that HBV possibly hijacks the glycerol-3-phosphate (G3P) shuttle. In this study, the two glycerol-3-phosphate dehydrogenases (GPD1 and GPD2) in the G3P shuttle were analyzed for determining their role in HBV replication and the findings revealed that GPD2 and not GPD1 inhibited HBV replication. The knockdown of GPD2 expression upregulated HBV replication, while GPD2 overexpression reduced HBV replication. Moreover, the overexpression of GPD2 significantly reduced HBV replication in hydrodynamic injection-based mouse models. Mechanistically, this inhibitory effect is related to the GPD2-mediated degradation of HBx protein by recruiting the E3 ubiquitin ligase TRIM28 and not to the alterations in G3P metabolism. In conclusion, this study revealed GPD2, a key enzyme in the G3P shuttle, as a host restriction factor in HBV replication. IMPORTANCE The glycerol-3-phosphate (G3P) shuttle is important for the delivery of cytosolic reducing equivalents into mitochondria for oxidative phosphorylation. The study analyzed two key components of the G3P shuttle and identified GPD2 as a restriction factor in HBV replication. The findings revealed a novel mechanism of GPD2-mediated inhibition of HBV replication via the recruitment of TRIM28 for degrading HBx, and the HBx-GPD2 interaction could be another potential therapeutic target for anti-HBV drug development.


Asunto(s)
Glicerolfosfato Deshidrogenasa , Hepatitis B , Proteína 28 que Contiene Motivos Tripartito , Proteínas Reguladoras y Accesorias Virales , Animales , Ratones , Glicerol/metabolismo , Glicerolfosfato Deshidrogenasa/metabolismo , Hepatitis B/metabolismo , Virus de la Hepatitis B/fisiología , Mitocondrias/enzimología , Fosfatos/metabolismo , Proteína 28 que Contiene Motivos Tripartito/metabolismo , Proteínas Reguladoras y Accesorias Virales/genética , Proteínas Reguladoras y Accesorias Virales/metabolismo , Replicación Viral
5.
Nanotechnology ; 35(35)2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38768574

RESUMEN

The development of 6 G networks has promoted related research based on terahertz communication. As submillimeter radiation, signal transportation via terahertz waves has several superior properties, including non-ionizing and easy penetration of non-metallic materials. This paper provides an overview of different terahertz detectors based on various mechanisms. Additionally, the detailed fabrication process, structural design, and the improvement strategies are summarized. Following that, it is essential and necessary to prevent the practical signal from noise, and methods such as wavelet transform, UM-MIMO and decoding have been introduced. This paper highlights the detection process of the terahertz wave system and signal processing after the collection of signal data.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39311974

RESUMEN

PURPOSE: To investigate differences in objective and subjective visual quality 12 months following Q value-guided (Custom-Q) femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) versus small incision lenticule extraction (SMILE) for correction of low-to-moderate myopia and compensate for age-related accommodation deficiency. METHODS: Clinical data of 45 patients were analyzed, of whom 23 were treated with FS-LASIK and 22 with SMILE. At the 12-month follow-up, the distance, intermediate, and near visual acuities; objective and subjective refractions; Q factor; corneal higher-order aberrations (HOAs); defocus curve; contrast sensitivity; stereopsis and a subjective visual quality questionnaire were evaluated. RESULTS: At 12 months postoperatively, the two groups had comparable binocular uncorrected distance and intermediate visual acuities (UDVA, UINA). A slightly better uncorrected near visual acuity (UNVA) was observed in the FS-LASIK group (P < 0.05), but patients reported equivalent near vision satisfaction and spectacle independence. Total HOAs and coma increased significantly in all treated eyes (P < 0.05). The Q value and spherical aberration (SA) became more positive, but the shifts were significant only in the SMILE group and the dominant eyes of the FS-LASIK group (P < 0.05). Binocular contrast sensitivity was better in the FS-LASIK group. No significant differences in visual disturbances were found between groups. CONCLUSION: For myopic patients with mild age-related accommodation deficiency, both FS-LASIK with Custom-Q protocol and SMILE could provide good efficacy, safety, predictability, and high patient satisfaction. The Custom-Q protocol could better preserve the original prolate shape of the cornea and achieve superior visual quality compared to SMILE. KEY MESSAGES: What is known Both femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and small-incision lenticule extraction (SMILE) have been widely applied in young myopic patients, with comparable efficacy and safety. Studies evaluating the clinical outcomes of FS-LASIK and SMILE in treating myopia with age-related accommodation insufficiency are lacking. What is new For myopic patients with mild age-related accommodation deficiency, both FS-LASIK with Custom-Q protocol and SMILE could provide good efficacy, safety, predictability, and high patient satisfaction. The Custom-Q protocol could better preserve the original prolate shape of the cornea and achieve superior visual quality compared to SMILE.

7.
BMC Ophthalmol ; 24(1): 325, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103855

RESUMEN

BACKGROUND: To analyze the clinical outcomes after topography-guided femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) with Phorcides Analytic Engine (PAE) algorithm or Custom-Q FS-LASIK for myopia with nonastigmatic eyes. METHODS: In this retrospective study, a total of 90 eyes with myopia without manifest astigmatism (82 patients) were included. All surgeries were performed by topography-guided FS-LASIK planned with a PAE algorithm (42 eyes) or Custom-Q system (48 eyes). Refractive, visual outcomes and corneal aberrations were compared between the two groups. RESULTS: At 6 months postoperatively, the postoperative uncorrected distance visual acuity (UDVA) was 20/20 or better in 42 eyes (100%) in the PAE compared with 44 eyes (92%) in Custom-Q (P = .120). The postoperative UDVA of 20/16 or better was measured in 92% of eyes in the PAE group and 81% of eyes in the Custom Q group (P = .320). Postoperative corrected distance visual acuity, manifest refractive spherical equivalent and refractive astigmatism were similar between the two groups (P > .05). The postoperative optical path difference (OPD) and Strehl ratio (SR) were significantly better in the PAE group compared with the Custom Q group. CONCLUSIONS: Topography-guided FS-LASIK with PAE algorithm or Custom Q demonstrated similar refractive efficacy and predictability. PAE for the patients with zero manifest astigmatism demonstrated better results in correcting corneal aberrations.


Asunto(s)
Topografía de la Córnea , Queratomileusis por Láser In Situ , Láseres de Excímeros , Miopía , Refracción Ocular , Agudeza Visual , Humanos , Queratomileusis por Láser In Situ/métodos , Estudios Retrospectivos , Agudeza Visual/fisiología , Masculino , Femenino , Miopía/cirugía , Miopía/fisiopatología , Adulto , Refracción Ocular/fisiología , Láseres de Excímeros/uso terapéutico , Adulto Joven , Resultado del Tratamiento , Cirugía Asistida por Computador/métodos
8.
BMC Ophthalmol ; 24(1): 87, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38408954

RESUMEN

BACKGROUND: To evaluate the difference in anterior chamber depth (ACD) between two eyes among keratoconus patients with binocular very asymmetric ectasia (VAE) and to explore the influencing factors. METHODS: The corneal curvature and ACD in both eyes of patients with VAE were measured by Sirius (version 3.2, CSO, Italy) at the following points: corneal vertex, maximum curvature (apex), and the 1.5 mm, 2.5 mm, and 3.5 mm superior-, inferior-, nasal-, temporal-paracentral from center. The mean pupil power (MPP) and corneal morphology parameters were also measured. Correlations between ACD and curvature and morphology parameters were analyzed by linear regression. RESULTS: 172 eyes of 86 patients (9 to 45 years) were classified into the VAE-N (n = 86) group and the VAE-E group (n = 86) based on the corneal morphology. The central (3.32 ± 0.27 mm versus 3.43 ± 0.29 mm, P < 0.001) and paracentral ACDs increased significantly in the VAE-E group, and the corneal morphology parameters were also significantly higher. The central ACD was significantly correlated with the MPP (r = 0.465), KVf/b (Keratoconus Vertex front/back) (r = 0.306, r = 0.327), and BCVf/b (Baiocchi Calossi Versaci front/back) (r = 0.356, r = 0.416). Linear regression showed good relationships between △ACD and △MPP (R2 = 0.429) and △KVf/b (R2 = 0.504, R2 = 0.536). CONCLUSIONS: The ACD was larger in the VAE-E group. The difference in ACD between the VAE-E and VAE-N groups was significantly correlated with corneal curvature and the extent of corneal elevation, indicating the influences of both the corneal magnification effect and corneal ectasia on ACD.


Asunto(s)
Queratocono , Humanos , Queratocono/complicaciones , Queratocono/diagnóstico , Topografía de la Córnea , Paquimetría Corneal , Dilatación Patológica , Córnea , Cámara Anterior
9.
Nano Lett ; 23(16): 7485-7492, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37477256

RESUMEN

The recycling of LiFePO4 from degraded lithium-ion batteries (LIBs) from electric vehicles (EVs) has gained significant attention due to resource, environment, and cost considerations. Through neutron diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy, we revealed continuous lithium loss during battery cycling, resulting in a Li-deficient state (Li1-xFePO4) and phase separation within individual particles, where olive-shaped FePO4 nanodomains (5-10 nm) were embedded in the LiFePO4 matrix. The preservation of the olive-shaped skeleton during Li loss and phase change enabled materials recovery. By chemical compensation for the lithium loss, we successfully restored the hybrid LiFePO4/FePO4 structure to pure LiFePO4, eliminating nanograin boundaries. The regenerated LiFePO4 (R-LiFePO4) exhibited a high crystallinity similar to the fresh counterpart. This study highlights the importance of topotactic chemical reactions in structural repair and offers insights into the potential of targeted Li compensation for energy-efficient recycling of battery electrode materials with polyanion-type skeletons.

10.
Angew Chem Int Ed Engl ; 63(10): e202316055, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38092695

RESUMEN

Tunnel-structured manganese dioxides (MnO2 ), also known as octahedral molecule sieves (OMS), are widely studied in geochemistry, deionization, energy storage and (electro)catalysis. These functionalities originate from their characteristic sub-nanoscale tunnel framework, which, with a high degree of structural polymorphism and rich surface chemistry, can reversibly absorb and transport various ions. An intensive understanding of their structure-property relationship is prerequisite for functionality optimization, which has been recently approached by implementation of advanced (in situ) characterizations providing significant atomistic sciences. This review will thus timely cover recent advancements related to OMS and their energy storage applications, with a focus on the atomistic insights pioneered by researchers including our group: the origins of structural polymorphism and heterogeneity, the evolution of faceted OMS crystals and its effect on electrocatalysis, the ion transport/storage properties and their implication for processing OMS. These studies represent a clear rational behind recent endeavors investigating the historically applied OMS materials, the summary of which is expected to deepen the scientific understandings and guide material engineering for functionality control.

11.
Angew Chem Int Ed Engl ; 63(18): e202401924, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38366134

RESUMEN

Nitrate electroreduction reaction (eNO3 -RR) to ammonia (NH3) provides a promising strategy for nitrogen utilization, while achieving high selectivity and durability at an industrial scale has remained challenging. Herein, we demonstrated that the performance of eNO3 -RR could be significantly boosted by introducing two-dimensional Cu plates as electrocatalysts and eliminating the general carrier gas to construct a steady fluid field. The developed eNO3 -RR setup provided superior NH3 Faradaic efficiency (FE) of 99 %, exceptional long-term electrolysis for 120 h at 200 mA cm-2, and a record-high yield rate of 3.14 mmol cm-2 h-1. Furthermore, the proposed strategy was successfully extended to the Zn-nitrate battery system, providing a power density of 12.09 mW cm-2 and NH3 FE of 85.4 %, outperforming the state-of-the-art eNO3 -RR catalysts. Coupled with the COMSOL multiphysics simulations and in situ infrared spectroscopy, the main contributor for the high-efficiency NH3 production could be the steady fluid field to timely rejuvenate the electrocatalyst surface during the electrocatalysis.

12.
J Virol ; 96(13): e0058522, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35862693

RESUMEN

The biogenesis of covalently closed circular DNA (cccDNA) from relaxed circular DNA (rcDNA) is essential for chronic hepatitis B virus (HBV) infection. Different host DNA repair proteins are involved in the conversion of rcDNA to cccDNA. Here, we reported that the DNA repair factor poly(ADP-ribose) polymerase 1 (PARP1) is engaged in HBV cccDNA formation. PARP1 depletion remarkably impaired HBV replication and cccDNA synthesis. Inhibition of PARP1 poly (ADP-ribosylation) activity by olaparib suppressed cccDNA synthesis both in vitro and in vivo. Specifically, the early stage of cccDNA reservoir establishment was more sensitive to olaparib, suggesting that PARP1 participated in de novo cccDNA formation. Furthermore, PARP1 was activated by recognizing the rcDNA-like lesions directly and combined with other DNA repair proteins. The results presented proposed that the DNA damage-sensing protein PARP1 and poly(ADP-ribosylation) modification play a key role in cccDNA formation, which might be the target for developing the anti-HBV drug. IMPORTANCE The biogenesis and eradication of HBV cccDNA have been a research priority in recent years. In this study, we identified the DNA repair factor PARP1 as a host factor required for the HBV de novo cccDNA formation. HBV infection caused PARylation through PARP1 in Huh7-NTCP cells, primary human hepatocytes, and human-liver chimeric mice. We found that PARP1 could directly bind to the rcDNA lesions and was activated, PARylating other DNA repair proteins. We address the importance of PARP1-mediated PARylation in HBV cccDNA formation, which is a potential therapeutic target for chronic hepatitis B.


Asunto(s)
ADN Circular , Hepatitis B , Poli(ADP-Ribosa) Polimerasa-1 , Animales , Reparación del ADN , ADN Circular/genética , ADN Circular/metabolismo , ADN Viral/genética , ADN Viral/metabolismo , Hepatitis B/virología , Virus de la Hepatitis B/genética , Humanos , Ratones , Poli(ADP-Ribosa) Polimerasa-1/genética , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Provirus/genética
13.
Graefes Arch Clin Exp Ophthalmol ; 261(6): 1731-1741, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36652015

RESUMEN

PURPOSE: To investigate the differences in surgical results and the objective and subjective quality of vision (QoV) of patients after small incision lenticule extraction (SMILE) versus alcohol-assisted photorefractive keratectomy (PRK). METHODS: Medical records of patients treated with SMILE and PRK were retrospectively examined. Visual quality, biometric parameters, Strehl ratio (SR), and corneal higher-order aberrations (HOAs) within a 6.0 mm area were recorded. The effective optical zone (EOZ) and decentration were measured using a tangential pre-post operation difference map. Subjective QoV and operation satisfaction were evaluated 6 months postoperatively using the Quality of Vision questionnaire. RESULTS: The study comprised 100 eyes treated with SMILE (preoperative mean spherical equivalent (SE), - 4.52 ± 0.81 dioptres (D)) and 69 eyes with PRK (mean SE, - 4.21 ± 1.25 D). Six months postoperatively, the EOZ reduction was significantly larger in the PRK group (P < 0.001). Decentrations were comparable between the groups. Regarding visual symptoms, monocular diplopia was more common following PRK (P = 0.02), and 98 (98.00%) SMILE-treated and 67 (97.10%) PRK-treated patients were satisfied with the QoV. Both groups demonstrated significant increases in total HOAs, coma, and spherical aberration (SA) at 6 months postoperatively compared to preoperatively (P < 0.001); these values were significantly higher in the PRK (P < 0.05) compared to the SMILE group. SR increased significantly only in the PRK group (P < 0.05). CONCLUSION: Although EOZ was more consistent with anticipated treatment and HOAs were fewer in SMILE, high patient-reported satisfaction and good corneal optical quality were achieved in both groups, indicating that both SMILE and alcohol-assisted PRK are excellent options for mild to moderate myopia correction.


Asunto(s)
Miopía , Queratectomía Fotorrefractiva , Humanos , Queratectomía Fotorrefractiva/métodos , Agudeza Visual , Estudios Retrospectivos , Láseres de Excímeros/uso terapéutico , Sustancia Propia/cirugía , Topografía de la Córnea , Refracción Ocular , Miopía/cirugía , Miopía/diagnóstico
14.
Int Ophthalmol ; 43(11): 3935-3942, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37410299

RESUMEN

PURPOSE: The purpose of the study was to characterize the subjective visual quality and satisfaction following small-incision lenticule extraction (SMILE) and to identify its influential factors. SETTING: Peking University Third Hospital, Beijing, China. DESIGN: This was a retrospective observational study. METHODS: Patients who had simultaneous binocular SMILE for myopia and myopic astigmatism were included 6 months postoperatively, and the patient-reported outcome questionnaire was employed for the assessment of visual quality in real-life situations. Examinations with SIRIUS combined corneal topography and tomography were performed including the parameters of Strehl ratio (SR), corneal higher-order aberrations (HOAs) within 6.0-mm area, kappa angel, and thinnest corneal thickness. Decentration and effective optical zone (EOZ) were measured based on a tangential pre-post-operation difference map. Binary logistic regression analysis was performed for predictors of patient-reported visual quality. RESULTS: Clinical data from 97 cases were analyzed retrospectively. Overall satisfaction was 96.91% (94/97). Fluctuation in vision and glare is the most frequent and dominant visual symptoms. SR value increased non-significantly compared with preoperative (P> 0.05). A statistically significant (P < 0.05) increase in total HOAs, spherical aberration, and coma was noted. SR and HOAs were not correlated with the degree of visual symptoms (P > 0.05). No objective parameter was found to be associated with patient-reported visual quality after SMILE (P> 0.05). CONCLUSION: The high patient-reported satisfaction confirmed the ideal effect on visual quality following SMILE in real-life situations, though some objective optical performances were not satisfying. It is very tolerant toward patients' conditions and mild deviations, and this study did not find factors affecting visual performances.


Asunto(s)
Cirugía Laser de Córnea , Aberración de Frente de Onda Corneal , Miopía , Humanos , Agudeza Visual , Estudios Retrospectivos , Cirugía Laser de Córnea/métodos , Córnea , Miopía/cirugía , Miopía/diagnóstico , Láseres de Excímeros , Refracción Ocular , Sustancia Propia/cirugía , Aberración de Frente de Onda Corneal/diagnóstico
15.
Angew Chem Int Ed Engl ; 62(20): e202302547, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36919817

RESUMEN

Non-equilibrium kinetic intermediates are usually preferentially generated instead of thermodynamic stable phases in the solid-state synthesis of layered oxides. Understanding the inherent complexity between thermodynamics and kinetics is important for designing high cationic ordering cathodes. Single-crystal strategy is an effective way to solve the intrinsic chemo-mechanical problems of Ni-rich cathodes. However, the synthesis of high-performance single-crystal is very challenging. Herein, the kinetic reaction path and the formation mechanism of non-equilibrium intermediates in the synthesis of single-crystal Co-free Ni-rich were explored. We demonstrate that the formation of non-equilibrium intermediate and the electrochemical-thermo-mechanical failure can be effectively inhibited by driving low-temperature topotactic lithiation. This work provides a basis for designing high-performance single-crystal Ni-rich layered oxides by regulating the defective structures.

16.
Angew Chem Int Ed Engl ; 62(30): e202305695, 2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37235524

RESUMEN

Redox flow batteries have been discussed as scalable and simple stationary energy storage devices. However, currently developed systems encounter less competitive energy density and high costs, restricting their wider application. There is a lack of appropriate redox chemistry, preferably based on active materials that are abundant in nature and show high solubility in aqueous electrolytes. A nitrogen-centered redox cycle operating between the limiting species ammonia and nitrate via an eight-electron redox reaction stayed practically unnoticed, albeit its ubiquity in biological processes. Ammonia or nitrate are world-scale chemicals with high aqueous solubility, and are then comparably safe. We demonstrate here the successful implementation of such a nitrogen-based redox cycle between ammonia and nitrate with eight-electron transfer as a catholyte for Zn-based flow batteries, which continuously worked for 12.9 days with 930 charging-discharging cycles. A very competitive energy density of 577 Wh L-1 can be reached, which is well above most reported flow batteries (e.g. 8 times the standard Zn-bromide battery), demonstrating that the nitrogen cycle with eight-electron transfer can offer promising cathodic redox chemistry for safe, affordable, and scalable high-energy-density storage devices.

17.
Angew Chem Int Ed Engl ; 62(37): e202307355, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37405901

RESUMEN

Co-based material catalysts have shown attractive application prospects in the 2 e- oxygen reduction reaction (ORR). However, for the industrial synthesis of H2 O2 , there is still lack of Co-based catalysts with high production yield rate. Here, novel cyclodextrin-supported Co(OH)2 cluster catalysts were prepared via a mild and facile method. The catalyst exhibited remarkable H2 O2 selectivity (94.2 % ~ 98.2 %), good stability (99 % activity retention after 35 h), and ultra-high H2 O2 production yield rate (5.58 mol gcatalyst -1 h-1 in the H-type electrolytic cell), demonstrating its promising industrial application potential. Density functional theory (DFT) reveals that the cyclodextrin-mediated Co(OH)2 electronic structure optimizes the adsorption of OOH* intermediates and significantly enhances the activation energy barrier for dissociation, leading to the high reactivity and selectivity for the 2 e- ORR. This work offers a valuable and practical strategy to design Co-based electrocatalysts for H2 O2 production.

18.
J Am Chem Soc ; 144(38): 17407-17415, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36121645

RESUMEN

The proton, as the cationic form of the lightest element-H, is regarded as most ideal charge carrier in "rocking chair" batteries. However, current research on proton batteries is still at its infancy, and they usually deliver low capacity and suffer from severe acidic corrosion. Herein, electrochemically activated metallic H1.75MoO3 nanobelts are developed as a stable electrode for proton storage. The electrochemically pre-intercalated protons not only bond directly with the terminal O3 site via strong O-H bonds but also interact with the oxygens within the adjacent layers through hydrogen bonding, forming a hydrogen-bonding network in H1.75MoO3 nanobelts and enabling a diffusion-free Grotthuss mechanism as a result of its ultralow activation energy of ∼0.02 eV. To the best of our knowledge, this is the first reported inorganic electrode exhibiting Grotthuss mechanism-based proton storage. Additionally, the proton intercalation into MoO3 with formation of H1.75MoO3 induces strong Jahn-Teller electron-phonon coupling, rendering a metallic state. As a consequence, the H1.75MoO3 shows an outstanding fast charging performance and maintains a capacity of 111 mAh/g at 2500 C, largely outperforming the state-of-art battery electrodes. More importantly, a symmetric proton ion full cell based on H1.75MoO3 was assembled and delivered an energy density of 14.7 Wh/kg at an ultrahigh power density of 12.7 kW/kg, which outperforms those of fast charging supercapacitors and lead-acid batteries.

19.
BMC Ophthalmol ; 22(1): 280, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35751042

RESUMEN

BACKGROUND: To assess the visual and refractive outcomes of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) concurrent with accelerated cross-linking (LASIK Xtra) compared with conventional FS-LASIK (convLASIK) for high myopia in Chinese individuals. METHODS: In this prospective, randomized, fellow-eye comparison study, 25 patients with high myopia were treated randomly with LASIK Xtra in one eye and convLASIK in the other. A 24-month follow-up was conducted, and the main outcome measures included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE) and corneal tomography. RESULTS: The UDVA was 0.09 ± 0.15 logMAR in the LASIK Xtra group, which was significantly worse than that in the convLASIK group 1 day postoperatively (P = .001), but the difference became nonsignificant from 1 week after surgery. The efficacy index was 0.88 ± 0.18 in the LASIK Xtra eyes and 0.99 ± 0.13 in the convLASIK eyes at 24 months (P = .028). Throughout the follow-up period, a slight myopic shift in the MRSE and keratometry values were observed in both groups without significant intergroup differences. The coefficient of determination was 0.9982 in the LASIK Xtra eyes and 0.9987 in the convLASIK eyes. The corneal density was significantly higher, and demarcation lines were visible in the first 6 months in LASIK Xtra eyes, but both signs of cross-linking gradually disappeared during follow-up. No severe complications were detected in either group. CONCLUSIONS: LASIK Xtra showed comparable safety and predictability with convLASIK for high myopia in Chinese, but lower efficacy and no greater stability was observed up to 24-month follow-up.


Asunto(s)
Queratomileusis por Láser In Situ , Miopía , China , Estudios de Seguimiento , Humanos , Láseres de Excímeros/uso terapéutico , Miopía/diagnóstico , Estudios Prospectivos , Refracción Ocular , Resultado del Tratamiento
20.
Acta Radiol ; 63(7): 923-932, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34058846

RESUMEN

BACKGROUND: Little is known about the value of dynamic contrast-enhanced (DCE) in combination with diffusion-weighted imaging (DWI) for the differentiation of lacrimal gland tumors. PURPOSE: To evaluate the ability of DCE and DWI in differentiating lacrimal gland tumors. MATERIAL AND METHODS: DCE and DWI were performed in 72 patients with lacrimal gland tumors. Time-intensity curve (TIC) patterns were categorized as type A, type B, type C, and type D. Apparent diffusion coefficient (ADC) was measured on DWI. Then, the diagnostic effectiveness of TIC in conjunction with ADC was assessed using classification and regression tree (CART) analysis. RESULTS: Type A tumors were all epithelial; they could be further separated into pleomorphic adenoma sand carcinomas. Type B tumors were all non-epithelial tumors, which could be further separated into benign inflammatory infiltrates (BIIs) and lymphomas. Type C tumors contained both carcinomas and non-epithelial tumors, which could be diagnosed into carcinomas, BIIs and lymphomas. Type D tumors were all PAs. The mean ADC of epithelial tumors was significantly higher than that of non-epithelial tumors, and the mean ADC values were significantly different between PAs and carcinomas. Besides, the mean ADC value of BIIs was higher than that of lymphomas. Therefore, the CART decision tree made by ADC and TIC had a predictive accuracy of 86.1%, differentiating lacrimal gland tumors effectively. CONCLUSION: Combined DCE and DWI-MRI can efficiently differentiate lacrimal gland tumors which can be of help to ophthalmologists in the diagnosis and treatment of these tumors.


Asunto(s)
Carcinoma , Neoplasias del Ojo , Aparato Lagrimal , Linfoma , Medios de Contraste , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Aparato Lagrimal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos
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