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1.
ACS Appl Mater Interfaces ; 14(1): 1478-1488, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34928125

RESUMO

Transparent flexible supercapacitors (TFSCs) are a tantalizing power supplier for future transparent flexible electronics. However, their energy density is far behind a practical level while maintaining high transparency. We report here a transparent flexible potassium-ion microcapacitor, and its high energy density (15.5 µWh cm-2) roots in the battery-supercapacitor hybrid storage mechanism and much enlarged working voltage (3 V), outperforming the state-of-the-art TFSC, which is generally based on an aqueous electrolyte and an asymmetric pseudocapacitive mechanism. From an electrode material perspective, a multidimensional topotactic host composite anode is designed in which the component not only performs energy storage by synchronous and reversible uptake of potassium ions and electrons into its host structure, but also mutually compensates individual weakness in functional and structural aspects, efficiently constructing a three-dimensional potassium-ion diffusion and electron transport system. This conceptual exhibition provides design principles at material and device levels for high-performance TFSCs.

2.
Medicine (Baltimore) ; 100(47): e27886, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34964756

RESUMO

RATIONALE: Extra-pulmonary tuberculosis (TB) has long been a diagnostic challenge for clinicians, often requiring extensive workup and invasive procedures, with the risk of significant complications. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a minimally invasive and highly accurate diagnostic modality for the evaluation of mediastinal and abdominal lymphadenopathy and masses. Several reports on the utility of EUS-FNA as a favorable method for diagnosing extrapulmonary TB have been published. PATIENT CONCERNS: A 54-year-old man complained of intermittent melena. DIAGNOSES: 18 fluorine-fluorodeoxyglucose positron emission tomography/computed tomography revealed suspected carcinoma metastasis. EUS-FNA did not reveal any evidence of malignancy. INTERVENTIONS AND OUTCOMES: Laparoscopy was performed, and frozen section pathology during surgery showed granulomas with focal necrosis. Mycobacterium tuberculosis polymerase chain reaction was positive, but acid-fast bacilli staining was negative. Anti-TB treatment was initiated, and the patient was advised to visit the local TB dispensary regularly. LESSONS: The presence of atypical inflammation of inadequate material or non-representative samples of extra-pulmonary TB was observed on EUS-FNA cytology. Mycobacterium tuberculosis polymerase chain reaction and acid fast bacilli should be performed to diagnose TB because of its higher sensitivity.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Endossonografia/métodos , Mediastino/diagnóstico por imagem , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose dos Linfonodos , Tuberculose Miliar/diagnóstico , Diagnóstico Diferencial , Granuloma/diagnóstico , Granuloma/etiologia , Granuloma/patologia , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X/métodos
3.
Small ; 16(48): e2004457, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33155379

RESUMO

Nano heterostructures relying on their versatile construction and the breadth of combined functionality have shown great potential in energy storage fields. Herein, 2D sandwiched MoSe2 /TiO2- x /graphene nano heterostructures are designed by integrating structural and functional effects of each component, aiming to address the rate capability and cyclic stability of MoSe2 for sodium ion capacitors (SICs). These 2D nano heterostructures based on graphene platform can facilitate the interfacial electron transport, giving rise to fast reaction kinetics. Meanwhile, the 2D open structure induces a large extent of surface capacitive contribution, eventually leading to a high rate capability (415.2 mAh g-1 @ 5 A g-1 ). An ultrathin oxygen deficient TiO2- x layer sandwiched in these nano heterostructures provides a strong chemical-anchoring regarding the products generated during the sodiation/desodiation process, securing the entire cyclic stability. The associated sodiation/desodiation mechanism is revealed by operando and ex situ characterizations, which exhibits a strong solid electrolyte interphase (SEI) dependence. The simulations verify the dependent sodiation products and enhanced heterostructural chemical-anchoring. Assembled SICs based on these nano heterostructures anode exhibit high initial Coulombic efficiency, energy/power densities, and long cycle life, shedding new light on the design of nano heterostructure electrodes for high performance energy storage application.

4.
ACS Appl Mater Interfaces ; 12(26): 29218-29227, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32490658

RESUMO

Performance degradation of lithium/sodium-ion capacitors (LICs/SICs) mainly originates from anode pulverization, particularly the alloying and conversion types, and has spurred research for alternatives with an insertion mechanism. Three-dimensional (3D) topotactic host materials remain much unexplored compared to two-dimensional (2D) ones (graphite, etc.). Herein, vanadium monophosphide (VP) is designed as a 3D topotactic host anode. Ex situ electrochemical characterizations reveal that there are no phase changes during (de)intercalation, which follows the topotactic intercalation mechanism. Computational simulations also confirm the metallic feature and topotactic structure of VP with a spacious interstitial position for the accommodation of guest species. To boost the electrochemical performance, carbon nano-onions (CNOs) are coupled with 3D VP. Superior specific capacity and rate capability of VP-CNOs vs lithium/sodium can be delivered due to the fast ion diffusion nature. An exceptional capacity retention of above 86% is maintained after 20 000 cycles, benefitting from the topotactic intercalation process. The optimized LICs/SICs exhibit high energy/power densities and an ultrastable lifespan of 20 000 cycles, which outperform most of the state-of-the-art LICs and SICs, demonstrating the potential of VP-CNOs as insertion anodes. This exploration would draw attention with regard to insertion anodes with 3D topotactic host topology and provide new insights into anode selection for LICs/SICs.

5.
Small ; 14(27): e1801335, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29845753

RESUMO

Inspired by a cactus spine and trichomes integrated fog collection system, a strategy is presented to design a micro/nanostructured conical spine and Janus membrane integrative system (MNCS+JM). In this strategy, the surface of conical spine can be covered with rough micro and nanostructure (MNCS), so that the tiny fog-droplets can be captured, coalesced, and transported. Janus membrane (JM) with inside hydrophobic surface and outside hydrophilic surface is further used to control the water collection in process of droplet transport when the Janus membrane is vertically placed with different positions on the MNCS, thus MNCS+JM propel the droplet continuously for transport-coalescence-transport in a circle of droplet transport and collection. It is demonstrated that a higher fog collection rate can be achieved effectively, which is attributed to a cooperation effect between the Laplace pressure in difference and the released surface energy in droplet coalescence, in addition to wettability force of superhydrophobic-hydrophilic difference in the Janus membrane. This strategy of MNCS+JM offers an insight into the surface of materials to control the droplet transport for water collection in efficiency, which is significant to be extended into the realms of applications such as high-efficiency water collection systems, microfluidics devices, and others.

6.
ACS Nano ; 10(12): 10681-10688, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27689385

RESUMO

An artificial periodic roughness-gradient conical copper wire (PCCW) can be fabricated by inspiration from cactus spines and wet spider silks. PCCW can harvest fog on periodic points of the conical surface from air and transports the drops for a long distance without external force, which is attributed to dynamic as-released energy generated from drop deformation in drop coalescence, in addition to both gradients of geometric curve (inducing Laplace pressure) and periodic roughness (inducing surface energy difference). It is found that the ability of fog collection can be related to various tilt-angle wires, thus a fog collector with an array system of PCCWs is further designed to achieve a continuous process of efficient water collection. As a result, the effect of water collection on PCCWs is better than previous results. These findings are significant to develop and design materials with water collection and water transport for promising application in fogwater systems to ease the water crisis.

7.
Adv Mater ; 27(34): 5057-62, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26198463

RESUMO

Smart anisotropic-unidirectional spreading is displayed on a wettable-gradient-aligned fibrous surface due to a synergetic directing effect from the aligned structure and the ratio of hydrophilic components.


Assuntos
Quitosana/química , Poliésteres/química , Molhabilidade , Anisotropia , Hidrodinâmica
8.
Sci Rep ; 5: 11209, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26061176

RESUMO

Directional control of droplets on a surface is an important issue for tasks of long-range liquid-transport, self-cleaning and water repellency. However, it is still challenging to control the structure motions in orientations so as to control the shedding-off of droplets. Herein, we report a novel dynamic magnetic responsive wall (DMRW) array on PDMS (polydimethylsiloxane)-based surface. The walls can easily tilt through the effect of the external magnet because of the magnetic material in the DMRW. The droplets can be shed off directionally on the surface. Particularly, with the shape recovery and flexible properties, it achieves simultaneous control of the tilt angles (0-60°) of DMRW for shedding-off of droplets with different volumes (1-15 µL) under magnetic action on DMRW. The mechanism of droplet shedding-off on DMRW is elucidated by theory of interfaces. It offers an insight into design of dynamic interface for water repellency. This strategy realizes the preparation of multifunctional, tunable and directional drive functions.

9.
Chem Commun (Camb) ; 50(73): 10651-4, 2014 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-25078129

RESUMO

A kind of bioinspired heterostructured bead-on-string fiber (BHBF), composed of poly-(methyl methacrylate) (PMMA) and titanium tetrachloride (TiCl4) hydrolyzed nanoparticles, was prepared via integrating a wet-assembly system, including PMMA electrospinning, fog of nanoparticles and water coalescence at multi-stages. The wet-assembly of BHBF was regulated by the difference in surface energy and Laplace pressure. Especially, BHBF is characteristic of a hydrophilic rough bead for excellent water collection ability.


Assuntos
Nanopartículas/química , Interações Hidrofóbicas e Hidrofílicas , Polimetil Metacrilato/química , Propriedades de Superfície , Titânio/química , Água/química
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