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1.
Chemistry ; : e202402095, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943462

RESUMO

In the cross-plane single-molecule junctions, the correlation between molecular aromaticity and conductance remained puzzling. Cross-plane break junction (XPBJ) provides new insight into understanding the role of aromaticity and conjugation to molecules on charge transport through the planar molecules. In this work, we investigated the modulation of cross-plane charge transport in pyrene derivatives by hydrogenation and substituents based on the XPBJ method that differs from those used in-plane transport. We measured the electrical conductance of the hydrogenated derivatives of the pyrenes and found that hydrogenation reduces conductance, and the fully hydrogenated molecule has the lowest conductance. Conductance of pyrene derivatives increased after substitution by both electron-donating and electron-withdrawing groups. By calculating, the trend in decreased conductance of hydrogenated pyrene was found to be consistent with the change in aromaticity. Electron-withdrawing substituents reduce the aromaticity of the molecule and narrow the HOMO-LUMO gap, while electron-donating groups increase the aromaticity but also narrow the gap. Our work reveals the potential of fine-tuning the structure of the pyrene molecule to control the cross-plane charge transport through the single-molecule junctions.

2.
Nano Lett ; 23(13): 6027-6034, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37387588

RESUMO

Electrodes play an essential role in controlling electrode-molecule coupling. However, conventional metal electrodes require linkers to anchor the molecule. Van der Waals interaction offers a versatile strategy to connect the electrode and molecule without anchor groups. Except for graphene, the potential of other materials as electrodes to fabricate van der Waals molecular junctions remains unexplored. Herein, we utilize semimetallic transition metal dichalcogenides (TMDCs) 1T'-WTe2 as electrodes to fabricate WTe2/metalated tetraphenylporphyrin (M-TPP)/WTe2 junctions via van der Waals interaction. Compared with chemically bonded Au/M-TPP/Au junctions, the conductance of these M-TPP van der Waals molecular junctions is enhanced by ∼736%. More importantly, WTe2/M-TPP/WTe2 junctions exhibit the tunable conductance from 10-3.29 to 10-4.44 G0 (1.15 orders of magnitude) via single-atom control, recording the widest tunable range of conductance for M-TPP molecular junctions. Our work demonstrates the potential of two-dimensional TMDCs for constructing highly tunable and conductive molecular devices.

3.
Small ; 19(16): e2206740, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36670093

RESUMO

All-solid-state sodium metal batteries paired with solid polymer electrolytes (SPEs) are considered a promising candidate for high energy-density, low-cost, and high-safety energy storage systems. However, the low ionic conductivity and inferior interfacial stability with Na metal anode of SPEs severely hinder their practical applications. Herein, an anion-trapping 3D fiber network enhanced polymer electrolyte (ATFPE) is developed by infusing poly(ethylene oxide) matrix into an electrostatic spun fiber framework loading with an orderly arranged metal-organic framework (MOF). The 3D continuous channel provides a fast Na+ transport path leading to high ionic conductivity, and simultaneously the rich coordinated unsaturated cation sites exposed on MOF can effectively trap anions, thus regulating Na+ concentration distribution for constructing stable electrolyte/Na anode interface. Based on such advantages, the ATFPE exhibits high ionic conductivity and considerable Na+ transference number, as well as enhanced interfacial stability. Consequently, Na/Na symmetric cells using this ATFPE possess cyclability over 600 h at 0.1 mA cm-2 without discernable Na dendrites. Cooperated with Na3 V2 (PO4 )3 cathode, the all-solid-state sodium metal batteries (ASSMBs) demonstrate significantly improved rate and cycle performances, delivering a high discharge capacity of 117.5 mAh g-1 under 0.1 C and rendering high capacity retention of 78.2% after 1000 cycles even at 1 C.

4.
Int Ophthalmol ; 43(10): 3549-3558, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37318667

RESUMO

PURPOSE: To evaluate whether the six-month repeated irradiation of 650 nm low-level red light (LLRL) decreases the risk of myopia onset in children. METHODS: This was a single-masked, randomized controlled trial. A total of 112 children (aged 6-12 years) were enrolled and randomized to the treatment group or control group in a 1:1 ratio. The cycloplegic spherical equivalent error (SER) of children at baseline was -0.5 diopter (D) to 3D. Children in the treatment group were irradiated with the 650 nm LLRL for 6 min daily. No intervention was given to the control. The primary outcomes are myopia incidence, change in cycloplegic SER, and change in axial length (AL). RESULTS: For the treatment group and control group, the six-month myopia incidence rates were 1.8% (95% confidence interval, CI: 0.2-4.9%) and 12.5% (95% CI: 5.5-21.9%), respectively. The difference was significant (p = 0.028). The median changes in AL for the treatment group and control group were -0.02 (interquartile range, IQR: -0.12 to 0.06) mm, and 0.09 (IQR: 0-0.18) mm, respectively. The difference was significant (p < 0.001). The median changes in cycloplegic SER for the treatment group and control group were 0 (IQR: 0-0.25) D, and -0.125 (IQR: -0.375 to 0) D, respectively. The difference was significant (p < 0.001). There was no adverse event. CONCLUSION: The repeated irradiation of 650 nm LLRL may have a strong effect for myopia prevention in children, without risk of adverse events. TRIAL REGISTRATION: this trial is retrospectively registered in the Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ), the registration number is ChiCTR2200058963.


Assuntos
Midriáticos , Miopia , Humanos , Criança , Miopia/epidemiologia , Refração Ocular , Luz , Incidência , Progressão da Doença
5.
Anal Chem ; 94(35): 12042-12050, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35971273

RESUMO

The tunneling current through the single-molecule junctions principally offers the ultimate solution for chemical and biochemical sensing via the interactions between probes and target analytes at the single-molecule level. However, it remains unexplored to achieve the sensitive and selective detection of targeted analytes using single-molecule junction techniques due to the challenge in quantitative evaluation of sensing sensitivity and selectivity. Herein, we demonstrate a single-molecule tunneling sensor for the highly sensitive and selective detection of nitrobenzene explosives using scanning tunneling microscope break junction (STM-BJ). Taking advantage of π-π stacking interactions between the molecular probes and nitrobenzene explosives, we use a spectral clustering algorithm to assign the signal of probes and π-stacked probes for sensitively detecting the targeted analytes and the distinguishable conductance change of probes when interacting with different nitroaromatic explosive compounds for selective detection. We find that pronounced conductance changes up to 0.8 orders of magnitude when the probes interact with TNT. Also, we obtain a sensitivity of up to ∼10 pM for TNT and high sensitivity for eight TNT analogues. Combined with theoretical calculations, we discover that the harness of the destructive quantum interference of the probe M1OH after interacting with TNT leads to high selectivity in sensing with TNT. Our work demonstrates the great potential of the single-molecule tunneling current for environmental sensing molecules with high selectivity and sensitivity.


Assuntos
Substâncias Explosivas , Nanotecnologia , Nitrobenzenos
6.
Small ; 18(52): e2205887, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344416

RESUMO

In this study, cuboid-like anhydrous CoC2 O4 particles (CoC2 O4 -HK) are synthesized through a potassium citrate-assisted hydrothermal method, which possess well-crystallized structure for fast Li+ transportation and efficient Li+ intercalation pseudocapacitive behaviors. When being used in lithium-ion batteries, the as-prepared CoC2 O4 -HK delivers a high reversible capacity (≈1360 mAh g-1 at 0.1 A g-1 ), good rate capability (≈650 mAh g-1 at 5 A g-1 ) and outstanding cycling stability (835 mAh g-1 after 1000 cycles at 1 A g-1 ). Characterizations illustrate that the Li+ -intercalation pseudocapacitance dominates the charge storage of CoC2 O4 -HK electrode, together with the reversible reaction of CoC2 O4 +2Li+ +2e- →Co+Li2 C2 O4 on discharging and charging. In addition, CoC2 O4 -HK particles are also used together with carbon-sulfur composite materials as the electrocatalysts for lithium-sulfur (Li-S) battery, which displays a gratifying sulfur electrochemistry with a high reversibility of 1021.5 mAh g-1 at 2 C and a low decay rate of 0.079% per cycle after 500 cycles. The density functional theory (DFT) calculations show that CoC2 O4 /C can regulate the adsorption-activation of reaction intermediates and therefore boost the catalytic conversion of polysulfides. Therefore, this work presents a new prospect of applying CoC2 O4 as the high-performance electrode materials for rechargeable Li-ion and Li-S batteries.

7.
Small ; 18(3): e2104554, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34796644

RESUMO

The host-guest interaction acts as an essential part of supramolecular chemistry, which can be applied in confined reaction. However, it is challenging to obtain the dynamic process during confined reactions below micromolar concentrations. In this work, a new method is provided to characterize the dimerization process of the guest 1,2-bis(4-pyridinyl) ethylene in host cucurbit[8]curil using scanning tunneling microscope-break junction (STM-BJ) technique. The guest reaction kinetics is quantitatively by nuclear magnetic resonance (NMR) and in situ single-molecule junctions. It is found that in the single-molecule conductance measurements, the electrical signals of the reactants with a concentration as low as 5 × 10-6  m are clearly detected, and the reaction kinetics at micromolar concentrations are further obtained. However, in NMR measurements, the characteristic peak signal of the reactants is undetectable when the concentration of the reactants is lower than 0.5 × 10-3  m and it cannot be quantified. In addition, the strong electric field from the nanogap accelerates the reaction. This work reveals that single-molecule STM-BJ techniques are more sensitive for tracking confined reactions than that by NMR techniques and can be used to study effect of extremely strong electric field on kinetics.


Assuntos
Nanotecnologia , Espectroscopia de Ressonância Magnética
8.
Ophthalmic Res ; 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36349785

RESUMO

INTRODUCTION: Acute acquired concomitant esotropia (AACE) has been increased dramatically in myopia. To clarify whether fusional vergence dysfunctions exist in AACE with myopia, and to explore the relationship between fusional vergence and myopia in AACE Methods: A prospective clinical study. Adult AACE patients as well as controls (aged ≥18 years) both with myopia were prospectively recruited from October 2016 to August 2021. Refractive error and fusional divergence and convergence amplitude at distance were measured, as determined with a comprehensive refractor. The main outcome measures were the real value of the fusional divergence amplitude (calculated by subtracting the break point value from the angle of deviation) and the real value of the fusional convergence amplitude (calculated by subtracting the angle of deviation from the break point value). Two-sided p value of less than 0.05 was considered to indicate statistical significance. RESULTS: Fusional vergence consisting of fusional divergence and fusional convergence in patients with AACE of adulthood were different from the controls (p<0.001), with fusional convergence decreased and fusional divergence increased. In the linear regression analysis, spherical equivalents were significantly negatively correlated with fusional convergence (right eyes, p<0.001; left eyes, p<0.001) in patients with AACE of adulthood but not in controls. There was a significant difference in fusional convergence amplitude among different degrees of spherical equivalents (p<0.001). CONCLUSIONS: Fusional vergence dysfunction exist in AACE of adulthood, which may be attributed to self-adaptation based on concomitant esotropia to maintain fusion in AACE. Fusional convergence was associated with degrees of myopia, implying the adaption would be weakened as the degree of myopia becomes serious.

9.
Small ; 16(39): e2003342, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32856380

RESUMO

Nickel-cobalt borides (denoted as NCBs) have been considered as a promising candidate for aqueous supercapacitors due to their high capacitive performances. However, most reported NCBs are amorphous that results in slow electron transfer and even structure collapse during cycling. In this work, a nanocrystallized NCBs-based supercapacitor is successfully designed via a facile and practical microimpinging stream reactor (MISR) technique, composed of a nanocrystallized NCB core to facilitate the charge transfer, and a tightly contacted Ni-Co borates/metaborates (NCBi ) shell which is helpful for OH- adsorption. These merits endow NCB@NCBi a large specific capacity of 966 C g-1 (capacitance of 2415 F g-1 ) at 1 A g-1 and good rate capability (633.2 C g-1 at 30 A g-1 ), as well as a very high energy density of 74.3 Wh kg-1 in an asymmetric supercapacitor device. More interestingly, it is found that a gradual in situ conversion of core NCBs to nanocrystallized Ni-Co (oxy)-hydroxides inwardly takes place during the cycles, which continuously offers large specific capacity due to more electron transfer in the redox reaction processes. Meanwhile, the electron deficient state of boron in metal-borates shells can make it easier to accept electrons and thus promote ionic conduction.

10.
Small ; 16(48): e2004720, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33155382

RESUMO

Recent progress in addressing electrically driven single-molecule behaviors has opened up a path toward the controllable fabrication of molecular devices. Herein, the selective fabrication of single-molecule junctions is achieved by employing the external electric field. For molecular junctions with methylthio (-SMe), thioacetate (-SAc), amine (-NH2 ), and pyridyl (-PY), the evolution of their formation probabilities along with the electric field is extracted from the plateau analysis of individual single-molecule break junction traces. With the increase of the electric field, the SMe-anchored molecules show a different trend in the formation probability compared to the other molecular junctions, which is consistent with the density functional theory calculations. Furthermore, switching from an SMe-anchored junction to an SAc-anchored junction is realized by altering the electric field in a mixed solution. The results in this work provide a new approach to the controllable fabrication and modulation of single-molecule junctions and other bottom-up nanodevices at molecular scales.

11.
Angew Chem Int Ed Engl ; 57(8): 2046-2070, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-28786158

RESUMO

Inorganic nanoparticles have become a research focus in numerous fields because of their unique properties that distinguish them from their bulk counterparts. Controlling the size and shape of nanoparticles is an essential aspect of nanoparticle synthesis. Preparing inorganic nanoparticles by using block copolymer templates is one of the most reliable routes for tuning the size and shape of nanoparticles with a high degree of precision. In this Review, we discuss recent progress in the design of block copolymer templates for crafting spherical inorganic nanoparticles including compact, hollow, and core-shell varieties. The templates are divided into two categories: micelles self-assembled from linear block copolymers and unimolecular star-shaped block copolymers. The precise control over the size and morphology of nanoparticles is highlighted as well as the useful properties and applications of such inorganic nanoparticles.

12.
Angew Chem Int Ed Engl ; 56(7): 1869-1872, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28105794

RESUMO

Well-controlled nanostructures and a high fraction of Sn/Li2 O interface are critical to enhance the coulombic efficiency and cyclic performance of SnO2 -based electrodes for lithium-ion batteries (LIBs). Polydopamine (PDA)-coated SnO2 nanocrystals, composed of hundreds of PDA-coated "corn-like" SnO2 nanoparticles (diameter ca. 5 nm) decorated along a "cob", addressed the irreversibility issue of SnO2 -based electrodes. The PDA-coated SnO2 were crafted by capitalizing on rationally designed bottlebrush-like hydroxypropyl cellulose-graft-poly (acrylic acid) (HPC-g-PAA) as a template and was coated with PDA to construct a passivating solid-electrolyte interphase (SEI) layer. In combination, the corn-like nanostructure and the protective PDA coating contributed to a PDA-coated SnO2 electrode with excellent rate capability, superior long-term stability over 300 cycles, and high Sn→SnO2 reversibility.

13.
Adv Sci (Weinh) ; 11(4): e2307134, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38032135

RESUMO

Sustainability and adaptability in structural design of the organic cathodes present promises for applications in alkali metal ion batteries. Nevertheless, a formidable challenge lies in their high solubility in organic electrolytes, particularly for small molecular materials, impeding cycling stability and high capacity. This study focuses on the design and synthesis of organic small molecules, the isomers of (E)-5,5'-difluoro-[3,3'-biindolinylidene]-2,2'-dione (EFID) and 3,9-difluoro-6,12-dihydrodibenzo [c, h][2,6]naphthyridine-5,11-dione (FBND). While EFID, characterized by a less π-conjugated structure, exhibits subpar cycling stability in lithium-ion batteries (LIBs), intriguingly, another isomer, FBND, demonstrates exceptional capacity and cycling stability in LIBs. FBND delivers a remarkable capacity of 175 mAh g-1 at a current density of 0.05 A g-1 and maintains excellent cycling stability over 2000 cycles, retaining 90% of its initial capacity. Furthermore, an in-depth examination of redox reactions and storage mechanisms of FBND are conducted. The potential of FBND is also explored as an anode in lithium-ion batteries (LIBs) and as a cathode in sodium-ion batteries (SIBs). The FBND framework, featuring extended π-conjugated molecules with an imide structure compared to EFID, proves to be an excellent material template to develop advanced organic small molecular cathode materials for sustainable batteries.

14.
Bioresour Technol ; 394: 130301, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211714

RESUMO

The purpose of this study is to design and investigate two coupling processes for acid-catalyzed hydrolysis of corncob, achieving the simultaneous preparation of biomass-based furfural and levulinic acid (LA). Meanwhile, high concentration and yield of LA were obtained through a situ feeding strategy of pretreated furfural residue with high solids loading (20%, w/v). In Scenario A, 2-methyltetrahydrofuran was selected as the solvent for the LA extraction process compared with the neutralization process in Scenario B. Techno-economic assessment results show that Scenario A is technically feasible and cost-competitive, with an internal rate of return of 21.92%, a net present value of 121 million US dollars, a carbon efficiency of 72%, an environmental factor of 4.38, and a process mass intensity of 32.19. This study will provide new insights for fully utilizing lignocellulosic biomass to prepare renewable energy resources, comprehensively evaluating the economic feasibility, and promoting green and low-carbon development.


Assuntos
Furaldeído , Zea mays , Furaldeído/química , Zea mays/química , Biomassa , Ácidos Levulínicos , Carbono
15.
JAMA Ophthalmol ; 142(6): 560-567, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38662345

RESUMO

Importance: Treatments are needed to slow progression of or reduce incidence of myopia. Objective: To evaluate the efficacy and safety of daily 650-nm low-level red light (LLRL) for myopia treatment. Design, Setting, and Participants: Single-masked, randomized clinical trial at 1 site in China. Baseline measurements were completed from August to September 2021. Participants were children aged 6 to 12 years with spherical equivalent error (SER) of -6 diopters (D) to 3 D. Data were analyzed from March to July 2023. Interventions: Irradiation daily with 650-nm LLRL for 3 minutes twice daily 4 or more hours apart or no intervention. Main Outcomes and Measures: Primary outcomes were changes in cycloplegia SER and axial length (AL) at 6- and 12-month follow-up visits. Safety was assessed on masked fundus photograph evaluations. Results: A total of 336 children were randomly allocated into the LLRL group or control group in a 1:1 ratio. The control group contained 86 female patients (51.2%), and the treatment group contained 90 female patients (53.6%). The mean (SD) age, SER, and AL were 9.0 (1.9) years, -1.3 (1.5) D, and 23.8 (1.0) mm for all patients. A total of 161 (95.8%) in the LLRL group and 159 (94.6%) in the control group returned for the 6-month follow-up. A total of 157 (93.5%) in the LLRL group and 152 (90.5%) in the control group returned for the 12-month follow-up. Mean (SD) changes in SER were 0.15 (0.16) D and -0.26 (0.21) D for the LLRL group and the control group, respectively (difference, -0.41 D; 95% CI, -0.48 to -0.34 D; P < .001), at 6 months and 0.24 (0.27) D and -0.65 (0.33) D for the LLRL group and the control group, respectively (difference, -0.89 D; 95% CI, -0.95 to -0.83 D; P < .001), at 12 months. Mean (SD) changes in AL were -0.06 (0.08) mm and 0.13 (0.12) mm for the LLRL group and control group, respectively (difference, 0.19 mm; 95% CI, 0.16 to 0.22 mm; P < .001), at 6 months and -0.11 (0.10) mm and 0.26 (0.16) mm for the LLRL group and control group, respectively (difference, 0.37 mm; 95% CI, 0.34 to 0.40 mm; P < .001). Masked fundus photograph review did not identify retinal changes in either group. Conclusions and relevance: These findings suggest daily use of 650-nm LLRL for 1 year can slow progression of SER and AL without safety concerns identified. Confirmation of these findings at independent sites seems warranted, as well as determining whether these effects can be sustained with or without continued treatment and whether LLRL has any effect on pathological myopia. Trial Registration: ChiCTR2200058963.


Assuntos
Comprimento Axial do Olho , Miopia , Refração Ocular , Acuidade Visual , Humanos , Feminino , Masculino , Criança , Comprimento Axial do Olho/diagnóstico por imagem , Miopia/fisiopatologia , Miopia/terapia , Refração Ocular/fisiologia , Método Simples-Cego , Acuidade Visual/fisiologia , Terapia com Luz de Baixa Intensidade/métodos , Resultado do Tratamento , Seguimentos , Luz Vermelha
16.
Zhonghua Yan Ke Za Zhi ; 49(7): 633-6, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24257360

RESUMO

OBJECTIVE: To evaluate the change of accommodation function after phakic posterior chamber implantable contact lens (PPC-ICL) implantation for high myopic eyes. METHODS: It was a retrospective case series study. PPC-ICL implantation surgery was performed in 36 eyes of 18 high myopic patients. Uncorrected visual acuity, best-corrected visual accuracy, amplitude of accommodation, pupil distance were tested and AC/A was calculated before, one month and three months after operation. Rank-sum test and variance analysis test was performed for statistic study. RESULTS: Before surgery, long-distance best corrected visual acuity was 0.55 (0.20, 1.50) for left eyes and 0.60 (0.10, 1.20) for right eyes. One and six months after surgery, it was 0.80 (0.40, 1.20), 0.85 (0.50, 1.50) for left eyes and 1.00 (0.30, 1.50), 0.95 (0.30, 1.50) for right eyes, all were improved. The difference between left and right eyes was statistically significant (W value 6.36, 6.18, P < 0.05). One and six months after surgery, uncorrected close-distance visual acuity was 1.00 (1.00, 4.00), 1.00 (1.00, 3.00) for left eyes and 1.00 (1.00, 4.00), 1.00 (1.00, 4.00) for right eyes. The difference for both eyes was not statistically significant compared with preoperative(W value 1.61, 2.72, P > 0.05). At one and six months after surgery, amplitude of accommodation was (8.28 ± 2.12) D, (8.28 ± 2.16) D for left eyes and (8.58 ± 1.98) D, (8.49 ± 2.10) D for right eyes, much better than the result (6.78 ± 1.96) D and (6.69 ± 2.14) D before surgery. The difference was statistically significant (F = 4.36, P < 0.05 and F = 4.04, P < 0.05). At one and six months after surgery, near and distant AC/A ratio were (3.96 ± 1.37) , (4.22 ± 1.33) , (4.78 ± 1.06) and (5.04 ± 1.01) , higher than (4.87 ± 0.97) and (5.23 ± 0.92) before surgery. The difference of near and distant AC/A ratio was statistically significant (F = 3.31, P < 0.05 and F = 4.10, P < 0.05). At one month and six months after surgery, near and distant pupil distance was (58.72 ± 2.78) mm, (61.56 ± 2.50) mm, (58.56 ± 2.4) mm and (61.61 ± 2.52) mm, smaller than that of (59.78 ± 2.39) mm and (62.44 ± 2.48) mm before surgery, but the difference was not statistically significant (F = 1.28, P > 0.05 and F = 0.76, P > 0.05). CONCLUSION: Accommodation parameters after PPC-ICL implantation are improved obviously compared with those before surgery.


Assuntos
Acomodação Ocular , Implante de Lente Intraocular , Miopia/fisiopatologia , Miopia/cirurgia , Adolescente , Adulto , Feminino , Humanos , Lentes Intraoculares , Masculino , Estudos Retrospectivos , Adulto Jovem
17.
Mater Horiz ; 10(5): 1769-1779, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36825539

RESUMO

Metamaterials, from concept to application level, is currently a high-trending topic. Due to the strict requirements of the simultaneous reasonable structural design and stability of materials, the construction of a high-performance metamaterial for extreme environments is still difficult. Here, combining metamaterial design with materials optimization, we propose a completely different strategy and synthesize a type of monomeric ceramic meta-atom to construct metamaterials. Based on a geometric design with multiple degrees of freedom and dielectric properties, hybrid anapole modes with impedance matching can be produced, experimentally inducing nearly perfect absorption with high temperature stability (high tolerable temperature of approximately 1300 °C, with almost zero temperature drift) in microwave/millimeter-wave bands. We surpass the oxidation temperature limitation of 800 °C in conventional plasmonic absorbers, and provide an unprecedented direction for the further development of integrated high-performance metamaterial wireless sensors responding to extreme environmental scenarios, which will also lead to a new direction of specific ceramic research toward device physics.

18.
ACS Appl Mater Interfaces ; 15(20): 24354-24365, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37167087

RESUMO

Antimony (Sb) has been considered a promising anode for sodium-ion batteries (SIBs) owing to its high theoretical capacity (660 mA h g-1) and low redox voltage (0.2-0.9 V vs Na+/Na). However, the capacity degradation caused by the volumetric variation during battery discharge/charge hinders the practical application. Herein, guided by the DFT calculation, Sb/Fe2S3 was fabricated by annealing Fe and Sb2S3 mixed powder. Next, Sb/Fe2S3 was blended with 15 wt % graphite by ball milling, yielding nano-Sb/Fe2S3 anchored on an exfoliated graphite composite (denoted as Sb/Fe2S3-15%). When applied as an anode of SIBs, Sb/Fe2S3-15% delivered reversible capacities of 565, 542, 467, 366, 285, and 236 mA h g-1 at current rates of 1, 2, 4, 6, 8, and 10 A g-1, respectively, surpassing most of the Sb-based anodes. The co-existence of highly conductive Fe2S3 and Sb minimizes the polarization of the anode. Our experiments proved that the Sb and Fe2S3 phases were reversible during discharge/charge cycling, and the exfoliated graphite can accelerate the Na+ diffusion and e- conduction. The proposed synthesis method of this work can also be applicable to synthesize various antimony/transition metal sulfide heterostructures (Sb/M1-xS), which may be applied in a series of fields.

19.
Chem Commun (Camb) ; 59(40): 6036-6039, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37099315

RESUMO

Nano-polycrystalline Sn2S3/Sn3S4/FeS/Fe7S8 sulfides anchored on graphene were synthesized via annealing SnS2 and Fe followed by homogeneously combining them with exfoliated graphite. When applied as an anode for a sodium-ion battery, the reversible capacity reached 863 mA h g-1 at 100 mA g-1. This facial materials synthesis method may be applied in various fields.

20.
Chemosphere ; 339: 139639, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37495052

RESUMO

As the development of urban population led to the increase of domestic water consumption, consequently the generation of surplus sludge (SS) produced increasingly during sewage treatment processes. In order to enhance the SS resource utilization efficiency, an electricity-assisted anaerobic digestion (EAAD) system was employed to examine the alterations in the digestion broth and the characteristics of gas production. Additionally, the response of applied voltages on the distribution of archaeal community near various electrodes within the sludge was explored. The results revealed that the application of high voltages exceeding 3.0 V hindered the CH4 production but stimulated the CO2 generation. Subsequently, both CH4 and CO2 production were impeded by the applied voltages. Furthermore, the increased voltages significantly decreased the abundance of Methanomicrobia, Methanosaeta, and Methanosarcina, which were crucial determinants of CH4 content in biogas. Notably, the excessively high voltages intensities caused the AD process to halt and even inactivate the microbial flora. Interestingly, the distribution characteristics of archaeal community were influenced not only by the voltages intensity but also exhibited variations between the anode and cathode regions. Moreover, as the applied voltage intensified, the discrepancy of responses between the cathode and anode regions became more pronounced, offering novel theoretical and technical foundations for the advancement of electricity-assisted with AD technology.


Assuntos
Archaea , Esgotos , Dióxido de Carbono , Anaerobiose , Metano , Biocombustíveis , Digestão , Reatores Biológicos
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