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1.
Nature ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658763

RESUMO

Replacement of liquid electrolytes with polymer gel electrolytes is recognized as a general and effective way of solving safety problems and achieving high flexibility in wearable batteries1-6. However, the poor interface between polymer gel electrolyte and electrode, caused by insufficient wetting, produces much poorer electrochemical properties, especially during the deformation of the battery7-9. Here we report a strategy for designing channel structures in electrodes to incorporate polymer gel electrolytes and to form intimate and stable interfaces for high-performance wearable batteries. As a demonstration, multiple electrode fibres were rotated together to form aligned channels, while the surface of each electrode fibre was designed with networked channels. The monomer solution was effectively infiltrated first along the aligned channels and then into the networked channels. The monomers were then polymerized to produce a gel electrolyte and form intimate and stable interfaces with the electrodes. The resulting fibre lithium-ion battery (FLB) showed high electrochemical performances (for example, an energy density of about 128 Wh kg-1). This strategy also enabled the production of FLBs with a high rate of 3,600 m h-1 per winding unit. The continuous FLBs were woven into a 50 cm × 30 cm textile to provide an output capacity of 2,975 mAh. The FLB textiles worked safely under extreme conditions, such as temperatures of -40 °C and 80 °C and a vacuum of -0.08 MPa. The FLBs show promise for applications in firefighting and space exploration.

2.
Lancet Infect Dis ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38614117

RESUMO

BACKGROUND: The Oka varicella vaccine strain remains neurovirulent and can establish lifelong latent infection, raising safety concerns about vaccine-related herpes zoster. In this study, we aimed to evaluate the immunogenicity and safety of a skin-attenuated and neuro-attenuated varicella vaccine candidate (v7D vaccine). METHODS: We did this randomised, double-blind, controlled, phase 2a clinical trial in Jiangsu, China. Healthy children aged 3-12 years with no history of varicella infection or vaccination were enrolled and randomly assigned (1:1:1:1) to receive a single subcutaneous injection of the v7D vaccine at 3·3 log10 plaque forming units (PFU; low-dose v7D group), 3·9 log10 PFU (medium-dose v7D group), and 4·2 log10 PFU (high-dose v7D group), or the positive control varicella vaccine (vOka vaccine group). All the participants, laboratory personnel, and investigators other than the vaccine preparation and management staff were masked to the vaccine allocation. The primary outcome was assessment of the geometric mean titres (GMTs) and seroconversion rates of anti-varicella zoster virus immunoglobulin G (IgG) induced by different dose groups of v7D vaccine at 0, 42, 60, and 90 days after vaccination in the per-protocol set for humoral immune response analysis. Safety was a secondary outcome, focusing on adverse events within 42 days post-vaccination, and serious adverse events within 6 months after vaccination. This study was registered on Chinese Clinical Trial Registry, ChiCTR2000034434. FINDINGS: On Aug 18-21, 2020, 842 eligible volunteers were enrolled and randomly assigned treatment. After three participants withdrew, 839 received a low dose (n=211), middle dose (n=210), or high dose (n=210) of v7D vaccine, or the vOka vaccine (n=208). In the per-protocol set for humoral immune response analysis, the anti-varicella zoster virus IgG antibody response was highest at day 90. At day 90, the seroconversion rates of the low-dose, medium-dose, and high-dose groups of v7D vaccine and the positive control vOka vaccine group were 100·0% (95% CI 95·8-100·0; 87 of 87 participants), 98·9% (93·8-100·0; 87 of 88 participants), 97·8% (92·4-99·7; 91 of 93 participants), and 96·4% (89·8-99·2; 80 of 83 participants), respectively; the GMTs corresponded to values of 30·8 (95% CI 26·2-36·0), 31·3 (26·7-36·6), 28·2 (23·9-33·2), and 38·5 (31·7-46·7). The v7D vaccine, at low dose and medium dose, elicited a humoral immune response similar to that of the vOka vaccine. However, the high-dose v7D vaccine induced a marginally lower GMT compared with the vOka vaccine at day 90 (p=0·027). In the per-protocol set, the three dose groups of the v7D vaccine induced a similar humoral immune response at each timepoint, with no statistically significant differences. The incidence of adverse reactions in the low-dose, medium-dose, and high-dose groups of v7D vaccine was significantly lower than that in the vOka vaccine group (17% [35 of 211 participants], 20% [41 of 210 participants], and 13% [27 of 210 participants] vs 24% [50 of 208 participants], respectively; p=0·025), especially local adverse reactions (10% [22 of 211 participants], 14% [30 of 210 participants] and 9% [18 of 210 participants] vs 18% [38 of 208 participants], respectively; p=0·016). None of the serious adverse events were vaccine related. INTERPRETATION: The three dose groups of the candidate v7D vaccine exhibit similar humoral immunogenicity to the vOka vaccine and are well tolerated. These findings encourage further investigations on two-dose vaccination schedules, efficacy, and the potential safety benefit of v7D vaccine in the future. FUNDING: The National Natural Science Foundation of China, CAMS Innovation Fund for Medical Sciences, the Fundamental Research Funds for the Central Universities, and Beijing Wantai. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

3.
J Vis ; 24(3): 6, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38512248

RESUMO

Transmission and processing of sensory information in the visual system takes time. For motion perception, our brain can overcome this intrinsic neural delay through extrapolation mechanisms and accurately predict the current position of a continuously moving object. But how does the system behave when the motion abruptly changes and the prediction becomes wrong? Here we address this question by studying the perceived position of a moving object with various abrupt motion changes by human observers. We developed a task in which a bar is monotonously moving horizontally, and then motion suddenly stops, reverses, or disappears-then-reverses around two vertical stationary reference lines. Our results showed that participants overestimated the position of the stopping bar but did not perceive an overshoot in the motion reversal condition. When a temporal gap was added at the reverse point, the perceptual overshoot of the end point scaled with the gap durations. Our model suggests that the overestimation of the object position when it disappears is not linear as a function of its speeds but gradually fades out. These results can thus be reconciled in a single process where there is an interplay of the cortical motion prediction mechanisms and the late sensory transient visual inputs.


Assuntos
Encéfalo , Percepção de Movimento , Humanos , Ácido Dioctil Sulfossuccínico , Movimento (Física) , Fenolftaleína
4.
Anat Sci Educ ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38487974

RESUMO

It can be difficult for some students to learn three-dimensional anatomical structure concepts. While virtual reality (VR) systems have been reported as helpful for learning, there has been scarce research on either VR teaching strategies or the influence of visually induced motion sickness (VIMS) in the context of large anatomy classes (i.e., over 100 students). The study thus aimed to (1) establish a VR anatomy instruction video for a large class; (2) determine how many students experience VIMS when watching a VR anatomy instruction video; (3) evaluate the influence of VIMS on VR anatomy video-based learning; and (4) examine whether a small screen size alleviates VIMS. Laboratory course students viewing a VR anatomy instruction video about the vascular system were invited to participate in the questionnaire survey. Anatomy faculty and staff participated in an experimental trial to determine whether small screen size could alleviate VIMS. The Likert scale survey revealed that students reported the VR strategy as advantageous and appropriate for large classes, but that it cannot replace practical dissection. Of the total participants, 32% reported experiencing VIMS, and 40% of those experiencing VIMS agreed that this could negatively impact their learning through a VR anatomy instruction video. Adjusting the screen size from large to small significantly delayed the onset of VIMS. In conclusion, the VR anatomy instruction video strategy is feasible and helpful for large classes, but educators should consider VIMS when planning their use of this teaching approach.

5.
Front Neurosci ; 18: 1360619, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482141

RESUMO

Introduction: Changes in vision that occur in normal healthy aging can be seen in fundamental measures of monocular vision. However, the nature of the changes in binocular vision with age remain unclear. Methods: A total of 28 older (53-66 years) and 28 younger adults (20-31 years) were enrolled in this study. We performed a battery of tests to assess differences in monocular contrast thresholds and various binocular visual functions including dichoptic masking weight and strength, the binocular balance point for fused stimuli, and stereoacuity in the aging and control groups. Results: Aging significantly increased monocular contrast thresholds (p < 0.001). Although this suggests that aging reduces the effective "input gain" to vision, we also found a significantly elevated contribution of those weaker signals to interocular suppression (p < 0.001). Consequently, there was no significant net difference in the strength of interocular suppression (p = 0.065). We did not find a significant difference of absolute balance point between the two groups (p = 0.090). Lastly, the mean stereoacuity was worse in the older group compared to the younger group (p = 0.002). Discussion: Our findings confirm previous results showing differences in contrast sensitivity and stereoacuity with aging. Furthermore, we find a change in interocular suppression that is a possible consequence of the change in contrast sensitivity. It is suggestive of a cortical system that maintains a homeostatic balance in interocular suppression across the lifespan.

6.
Nature ; 626(7998): 313-318, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326591

RESUMO

Calcium-oxygen (Ca-O2) batteries can theoretically afford high capacity by the reduction of O2 to calcium oxide compounds (CaOx) at low cost1-5. Yet, a rechargeable Ca-O2 battery that operates at room temperature has not been achieved because the CaOx/O2 chemistry typically involves inert discharge products and few electrolytes can accommodate both a highly reductive Ca metal anode and O2. Here we report a Ca-O2 battery that is rechargeable for 700 cycles at room temperature. Our battery relies on a highly reversible two-electron redox to form chemically reactive calcium peroxide (CaO2) as the discharge product. Using a durable ionic liquid-based electrolyte, this two-electron reaction is enabled by the facilitated Ca plating-stripping in the Ca metal anode at room temperature and improved CaO2/O2 redox in the air cathode. We show the proposed Ca-O2 battery is stable in air and can be made into flexible fibres that are weaved into textile batteries for next-generation wearable systems.

7.
Nat Commun ; 15(1): 944, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296971

RESUMO

Rechargeable calcium (Ca) metal batteries are promising candidates for sustainable energy storage due to the abundance of Ca in Earth's crust and the advantageous theoretical capacity and voltage of these batteries. However, the development of practical Ca metal batteries has been severely hampered by the current cathode chemistries, which limit the available energy and power densities, as well as their insufficient capacity retention and low-temperature capability. Here, we describe the rechargeable Ca/Cl2 battery based on a reversible cathode redox reaction between CaCl2 and Cl2, which is enabled by the use of lithium difluoro(oxalate)borate as a key electrolyte mediator to facilitate the dissociation and distribution of Cl-based species and Ca2+. Our rechargeable Ca/Cl2 battery can deliver discharge voltages of 3 V and exhibits remarkable specific capacity (1000 mAh g-1) and rate capability (500 mA g-1). In addition, the excellent capacity retention (96.5% after 30 days) and low-temperature capability (down to 0 °C) allow us to overcome the long-standing bottleneck of rechargeable Ca metal batteries.

8.
Proc Natl Acad Sci U S A ; 121(4): e2311732121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38232289

RESUMO

Rechargeable lithium (Li) metal batteries face challenges in achieving stable cycling due to the instability of the solid electrolyte interphase (SEI). The Li-ion solvation structure and its desolvation process are crucial for the formation of a stable SEI on Li metal anodes and improving Li plating/stripping kinetics. This research introduces an interfacial desolvation coating technique to actively modulate the Li-ion solvation structure at the Li metal interface and regulate the participation of the electrolyte solvent in SEI formation. Through experimental investigations conducted using a carbonate electrolyte with limited compatibility to Li metal, the optimized desolvation coating layer, composed of 12-crown-4 ether-modified silica materials, selectively displaces strongly coordinating solvents while simultaneously enriching weakly coordinating fluorinated solvents at the Li metal/electrolyte interface. This selective desolvation and enrichment effect reduce solvent participation to SEI and thus facilitate the formation of a LiF-dominant SEI with greatly reduced organic species on the Li metal surface, as conclusively verified through various characterization techniques including XPS, quantitative NMR, operando NMR, cryo-TEM, EELS, and EDS. The interfacial desolvation coating technique enables excellent rate cycling stability (i.e., 1C) of the Li metal anode and prolonged cycling life of the Li||LiCoO2 pouch cell in the conventional carbonate electrolyte (E/C 2.6 g/Ah), with 80% capacity retention after 333 cycles.

9.
Angew Chem Int Ed Engl ; 62(37): e202306789, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37455280

RESUMO

Chlorine (Cl)-based batteries such as Li/Cl2 batteries are recognized as promising candidates for energy storage with low cost and high performance. However, the current use of Li metal anodes in Cl-based batteries has raised serious concerns regarding safety, cost, and production complexity. More importantly, the well-documented parasitic reactions between Li metal and Cl-based electrolytes require a large excess of Li metal, which inevitably sacrifices the electrochemical performance of the full cell. Therefore, it is crucial but challenging to establish new anode chemistry, particularly with electrochemical reversibility, for Cl-based batteries. Here we show, for the first time, reversible Si redox in Cl-based batteries through efficient electrolyte dilution and anode/electrolyte interface passivation using 1,2-dichloroethane and cyclized polyacrylonitrile as key mediators. Our Si anode chemistry enables significantly increased cycling stability and shelf lives compared with conventional Li metal anodes. It also avoids the use of a large excess of anode materials, thus enabling the first rechargeable Cl2 full battery with remarkable energy and power densities of 809 Wh kg-1 and 4,277 W kg-1 , respectively. The Si anode chemistry affords fast kinetics with remarkable rate capability and low-temperature electrochemical performance, indicating its great potential in practical applications.

10.
ACS Appl Mater Interfaces ; 15(31): 37497-37503, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37497557

RESUMO

Rechargeable lithium metal batteries (LMBs) using high-voltage cathodes have been attractive in delivering high-energy density, but it is still challenging to reach excellent cycling performance for practical applications due to the notorious reactivity of metallic lithium as well as the unstable nature of the cathode. Here, we demonstrate a formulated carbonated-based electrolyte with LiPF6 that supports the most commercial aggressive and high-voltage cathode with the combination of cosolvent, diluent, and additives to address the issue in LMBs by providing a stable interface/interphase on both the anode and cathode. The electrolyte's solvation structure is adjusted to reduce free carbonate solvents in the decomposition and contribution to the solid-electrolyte interphase (SEI) formation. The thin LiF-rich SEI and achieved uniform Li deposition afforded a high Coulombic efficiency of 99.5% for Li|Cu half cells and good cycling stability in Li||NMC811 full cells. The Li||NMC811 full cells showed good cycling life with a capacity retention of ∼80% over 280 cycles at an areal capacity of 4.0 mAh cm-2, the lean electrolyte of 5 µL mAh-1, and a thin 50 µm Li metal, demonstrating its advantage toward practical applications.

11.
Angew Chem Int Ed Engl ; 62(27): e202304978, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37139890

RESUMO

Anode-free lithium (Li) metal batteries are desirable candidates in pursuit of high-energy-density batteries. However, their poor cycling performances originated from the unsatisfactory reversibility of Li plating/stripping remains a grand challenge. Here we show a facile and scalable approach to produce high-performing anode-free Li metal batteries using a bioinspired and ultrathin (250 nm) interphase layer comprised of triethylamine germanate. The derived tertiary amine and Lix Ge alloy showed enhanced adsorption energy that significantly promoted Li-ion adsorption, nucleation and deposition, contributing to a reversible expansion/shrinkage process upon Li plating/stripping. Impressive Li plating/stripping Coulombic efficiencies (CEs) of ≈99.3 % were achieved for 250 cycles in Li/Cu cells. In addition, the anode-free LiFePO4 full batteries demonstrated maximal energy and power densities of 527 Wh kg-1 and 1554 W kg-1 , respectively, and remarkable cycling stability (over 250 cycles with an average CE of 99.4 %) at a practical areal capacity of ≈3 mAh cm-2 , the highest among state-of-the-art anode-free LiFePO4 batteries. Our ultrathin and respirable interphase layer presents a promising way to fully unlock large-scale production of anode-free batteries.

12.
Carbohydr Polym ; 314: 120945, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37173045

RESUMO

Towards the difficulties of traditional processing technology in loading high-concentration functional fillers to realize the target electromagnetic interference shielding (EMI SE) performance, and constructing the arbitrary-designated architectures for serving advanced electronics, this work innovatively formulated a functional multi-walled carbon nanotubes@cellulose nanofibers (MWCNT@OCNF) ink for direct ink writing (DIW) 3D printing, which not only possessed high freedom on the proportion of functional particles, but also imparted to the ideal rheological performance for 3D printing. Based on the pre-programmed printing trajectories, a series of porous scaffolds featuring exceptional functionalities were architected. Particularly for the electromagnetic waves (EMWs) shielding behaviors, the optimized one with "full-mismatched" architecture posed the ultralight structure (0.11 g/cm3) and superior SE performance (43.5 dB) in the X-band frequency region. More encouragingly, the 3D-printed scaffold with hierarchical pores possessed the ideal electromagnetic compatibility on EMWs signal, where the radiation intensity generated by EMWs signal fluctuated in a step pattern in 0 and 1500 µT/cm2 as loading and unloading scaffolds. Overall, this study paved a novel path for the formulation of functional inks to print lightweight, multi-structure, and high-efficiency EMI SE scaffolds for the next-generation shielding elements.

13.
Angew Chem Int Ed Engl ; 62(24): e202303616, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37040128

RESUMO

Fiber lithium-ion batteries represent a promising power strategy for the rising wearable electronics. However, most fiber current collectors are solid with vastly increased weights of inactive materials and sluggish charge transport, thus resulting in low energy densities which have hindered the development of fiber lithium-ion batteries in the past decade. Here, a braided fiber current collector with multiple channels was prepared by multi-axial winding method to not only increase the mass fraction of active materials, but also to promote ion transport along fiber electrodes. In comparison to typical solid copper wires, the braided fiber current collector hosted 139 % graphite with only 1/3 mass. The fiber graphite anode with braided current collector delivered high specific capacity of 170 mAh g-1 based on the overall electrode weight, which was 2 times higher than that of its counterpart solid copper wire. The resulting fiber battery showed high energy density of 62 Wh kg-1 .

14.
Nat Commun ; 14(1): 1895, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019929

RESUMO

Lithium-sulfur all-solid-state batteries using inorganic solid-state electrolytes are considered promising electrochemical energy storage technologies. However, developing positive electrodes with high sulfur content, adequate sulfur utilization, and high mass loading is challenging. Here, to address these concerns, we propose using a liquid-phase-synthesized Li3PS4-2LiBH4 glass-ceramic solid electrolyte with a low density (1.491 g cm-3), small primary particle size (~500 nm) and bulk ionic conductivity of 6.0 mS cm-1 at 25 °C for fabricating lithium-sulfur all-solid-state batteries. When tested in a Swagelok cell configuration with a Li-In negative electrode and a 60 wt% S positive electrode applying an average stack pressure of ~55 MPa, the all-solid-state battery delivered a high discharge capacity of about 1144.6 mAh g-1 at 167.5 mA g-1 and 60 °C. We further demonstrate that the use of the low-density solid electrolyte increases the electrolyte volume ratio in the cathode, reduces inactive bulky sulfur, and improves the content uniformity of the sulfur-based positive electrode, thus providing sufficient ion conduction pathways for battery performance improvement.

15.
Lab Chip ; 23(7): 1955, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36938970

RESUMO

Correction for 'Virtual microwells for digital microfluidic reagent dispensing and cell culture' by Irwin A. Eydelnant et al., Lab Chip, 2012, 12, 750-757, https://doi.org/10.1039/C2LC21004E.

16.
J Cardiothorac Surg ; 18(1): 87, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941619

RESUMO

PURPOSE: Noninvasive coronary CT angiography (CCTA) was used to retrospectively analyze the characteristics of coronary artery disease (CAD) in patients with thoracic tumors and the impact of the results on clinical surgery decision-making, thus increasing the understanding of perioperative cardiac risk evaluation. METHOD: A total of 779 patients (age 68.6 ± 6.6 years) with thoracic tumor (lung, esophageal, and mediastinal tumor) scheduled for non-cardiac surgery were retrospectively enrolled. Patients were divided into two groups: accepted or canceled surgery. Clinical data and CCTA results were compared between the two groups, and multivariate logistic regression analysis was performed to determine predictors of the events of cancellations of scheduled surgeries. RESULTS: 634 patients (81.4%) had non-significant CAD and 145 patients (18.6%) had significant CAD. Single­, 2­, and 3­ vessel disease was found in 173 (22.2%), 93 (11.9%) and 50 (6.4%) patients, respectively. 500 (64.2%), 96 (12.3%), 96 (12.3%), 56 (7.2%) and 31 (4.0%) patients were rated as CACS 0, 1-99, 100-399, 400-999 and > 1000, respectively. Cancellations of scheduled procedures continue to increase based on the severity of the stenosis and the number of major coronary artery stenosis. The degree of stenosis and the number of vascular stenosis were independent predictors of cancelling scheduled surgery. CONCLUSIONS: For patients with thoracic tumors scheduled for non-cardiac surgery, the results suggested by CCTA significantly influenced surgery planning and facilitated to reduce perioperative cardiovascular events.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Neoplasias Torácicas , Humanos , Pessoa de Meia-Idade , Idoso , Angiografia por Tomografia Computadorizada , Estudos Retrospectivos , Constrição Patológica , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Valor Preditivo dos Testes , Neoplasias Torácicas/diagnóstico por imagem , Neoplasias Torácicas/cirurgia
17.
Eur J Dent Educ ; 27(4): 1077-1087, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36976652

RESUMO

INTRODUCTION: Modified teaching strategies (MTS), asynchronous online teaching and smaller dissection groups, were applied to a gross anatomy course for dental students in the National Taiwan University in April 2020 in response to the COVID-19 pandemic. This study aimed to investigate the effects and perceptions of MTS on dental students. MATERIALS AND METHODS: Scores for anatomy examinations for 2018-2019 (without MTS) and 2019-2020 (with MTS) cohorts were compared to explore the effect on academic performance. Moreover, questionnaire from the 2019-2020 cohort was analysed to determine dental students' perceptions about MTS. RESULTS: The lecture performance in the final examination of the second semester for the 2019-2020 cohort was significantly higher than that of the first semester (pre-COVID-19) and that for the 2018-2019 cohort. However, the laboratory performance in the midterm examination of the second semester for the 2019-2020 cohort was significantly lower than that for the 2018-2019 cohort and showed no difference in the final examination of the first semester. The questionnaires revealed that the majority of students displayed positive attitudes towards MTS and agreed with the importance of peer discussion during laboratory dissection. CONCLUSIONS: Asynchronous online learning for anatomy lecture may be beneficial for dental students; however, a smaller dissection group accompanied by reduced peer discussion may temporarily exert negative effects on their laboratory performance at the beginning of the application. Furthermore, more dental students exhibited positive perceptions towards smaller dissection groups. These findings could illuminate the learning condition of dental students in anatomy education.


Assuntos
Desempenho Acadêmico , Anatomia , COVID-19 , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Aprendizagem , Estudantes de Odontologia , Pandemias , Educação em Odontologia , Anatomia/educação , Ensino , Currículo
18.
Angew Chem Int Ed Engl ; 62(17): e202300705, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36849706

RESUMO

Flexible batteries based on gel electrolytes with high safety are promising power solutions for wearable electronics but suffer from vulnerable electrode-electrolyte interfaces especially upon complex deformations, leading to irreversible capacity loss or even battery collapse. Here, a supramolecular sol-gel transition electrolyte (SGTE) that can dynamically accommodate deformations and repair electrode-electrolyte interfaces through its controllable rewetting at low temperatures is designed. Mediated by the micellization of polypropylene oxide blocks in Pluronic and host-guest interactions between α-cyclodextrin (α-CD) and polyethylene oxide blocks, the high ionic conductivity and compatibility with various salts of SGTE afford resettable electrode-electrolyte interfaces and thus constructions of a series of highly durable, flexible aqueous zinc batteries. The design of this novel gel electrolyte provides new insights for the development of flexible batteries.

19.
Int J Ophthalmol ; 16(1): 10-15, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36659951

RESUMO

AIM: To compare the feature of ocular trauma between normalized period and the COVID-19 epidemic period in China, and to provide a profile for eye injuries in special times in future. METHODS: This is a multi-center cross-sectional study with 30 participated hospitals involving the China Ocular Trauma Society members. All hospitalized cases who visited the Ophthalmology Department in participated hospitals with eye injuries during the normalized period (2019) and the COVID-19 epidemic period (2020) were included in this study. Demographic characteristic of cases, date of injury, sites and types of injury were collected. RESULTS: This study involved 13 525 (61 cases with both eyes) injured cases. There were 7269 (53.74%) eye-injured cases and 6256 (46.26%) eye-injured cases in 2019 and 2020 separately. Compared with 2019, the incidence of ocular trauma in retirees, housewives and unemployed increased with year-on-year of 4.96%, 102.67%, and 11.64% among all occupations. In 2020, the incidence of eye injuries decreased in all injury sites except for an increase in home (30.29% year-on-year). The incidence of mechanical eye injuries decreased, while that of non-mechanical eye injuries (chemical/thermal/radiation) increased (47.45% year-on-year). There were 255 (3.51%, 255/7269) and 376 (6.01%, 376/6256) non-mechanical injured cases in 2019 and 2020 (Pearson Chi2=47.33, P<0.001) separately. CONCLUSION: During the COVID-19 epidemic period, the total cases of ocular trauma decrease but the proportion of non-mechanical ocular trauma increase. Penetrating is still the highest proportion among all types of mechanical ocular trauma. From a preventive point of view, protection for retired persons, housewives and unemployed persons should be improved during public health events period.

20.
Environ Technol ; 44(27): 4188-4198, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35608968

RESUMO

Solar photothermal water evaporation technology has attracted attention owing to its promising applications in wastewater treatment and desalination for producing clean water. However, high-performance solar evaporators are still limited by the complex manufacturing process, less flexibility, intolerance to salt, high cost, and low water evaporation efficiency.In this study, composite fibre paper composed of waste tissue paper, aramid nanofibers, and polyaniline was prepared to produce clean water. The evaporator was designed to pump water through a cotton wick to the composite paper, which reduced heat loss and avoided the deposition of salt on the surface. The use of waste tissue paper solves the problem of waste disposal, increases the commercial value of waste tissue, and reduces production costs. The composite fibre paper exhibited broad-band light absorption of an average of 96%. The average evaporation rate of the solar evaporator was 1.43 kg m-2 h-1, and the photothermal conversion efficiency was 98.33% under 1 sun illumination. This solar evaporator is easily fabricated and is cost-effective, demonstrating the enormous potential for real-world wastewater treatment and desalination to produce clean water.


Assuntos
Nanofibras , Eliminação de Resíduos , Água
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