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1.
Biomacromolecules ; 23(10): 4110-4117, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-36070358

RESUMEN

Recent advances of photonic crystals are driven to mechanical sensors and smart wearable devices; however, for chiral photonic cellulose nanocrystal (CNC) materials, vivid structural coloration and reversible mechanochromism like chameleon skin remain a big challenge. Here, we report a ternary co-assembly and post-UV-irradiation polymerization strategy to develop flexible and elastic CNC composite films, which, notably, have naked-eye-visible brilliant structural colors and stretching-induced color change covering a broad wavelength region at a moderate deformation (like skin). By adjusting the stretching, the film is designed as a smart skin to adapt to surrounding environments for camouflage. This work offers a universal strategy for constructing biomimic optically functional cellulose skins.


Asunto(s)
Celulosa , Nanopartículas , Celulosa/química , Nanopartículas/química , Óptica y Fotónica
2.
ACS Appl Mater Interfaces ; 14(6): 7805-7813, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35104097

RESUMEN

High energy density dielectric film capacitors are desirable in modern electronic devices. Their miniaturization and integration into Si-based microsystems create opportunities for in-circuit energy supply, buffering, and conditioning. Here, we present a CMOS (complementary metal oxide semiconductor)-compatible route for the fabrication of BaTiO3 film capacitors on Si with a record-high recoverable energy density and good efficiency (∼242 J/cm3 and ∼76% at 8.75 MV/cm). These BaTiO3 films were sputter-deposited at 350 °C and consisted of slightly compressed superfine columnar nanograins with a (001) texture. Such a nanostructure was endowed with a high breakdown strength, a reduced remnant polarization, and an enhanced maximum polarization, which are accountable for their excellent energy storage performance. Moreover, these BaTiO3 film capacitors displayed a high electrical fatigue resistance, a wide range of operating temperatures, and an excellent frequency stability. With an engineered nanostructure, the prototype perovskite of BaTiO3 has shown great promise for capacitive energy storage applications.

3.
ACS Appl Mater Interfaces ; 13(19): 22717-22727, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-33956442

RESUMEN

BaTiO3-based ferroelectrics have been extensively studied due to their large dielectric constants and a high saturated polarization, which have the potential to store or supply electricity of very high energy and power densities. In order to further improve the energy efficiency η and the recyclable energy density Wrec, an A, B-site co-doped (Ba0.95,Sr0.05)(Zr0.2,Ti0.8)O3 ceramic target was used for sputter deposition of film capacitor structures on Si. This film composition reduces the remnant polarization Pr, while the choice of a low-temperature, templated sputtering process facilitates the formation of high-density arrays of columnar nanograins (average diameter d ∼20 nm) and grain boundary dead layers. This self-assembled nanostructure further delays the saturation of the electric polarization, leading to a high energy density Wrec of ∼148 J/cm3 and a high energy efficiency η of ∼90%. Moreover, the (Ba0.95,Sr0.05)(Zr0.2,Ti0.8)O3 film capacitors retain their high energy storage performance in a broad range of working temperature (-175-300 °C) and operating frequency (1 Hz-20 kHz). They are also fatigue-free after up to 2 × 109 switching cycles. Our work provides a new method and a cost-effective processing route for the creation and integration of high-performance dielectric capacitors for energy storage applications.

4.
Zootaxa ; 4378(3): 377-386, 2018 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-29690008

RESUMEN

Genus Rambutanura Deharveng, 1988 of subfamily Neanurinae is herein recorded and a new species is described from China. A key to the species of the whole world of the genus is provided. In order to determine the new species, a new diagnosis within the genus Rambutanura Deharveng, 1988 is proposed. The new species is distinguished from all known members of the genus by its unique set of morphological characters notably: 2+2 depigmented eyes, mandible quadridentate, presence of 1 additional s-chaeta on each tubercle Di from Th. I to Abd. IV, presence of 2 additional s-chaetae on tubercle Dl from Abd. I to Abd. V, presence of guard chaetae sgd and sgv on AOIII, absence of digitate body tubercles.


Asunto(s)
Artrópodos , Distribución Animal , Estructuras Animales , Animales , China , Ojo
5.
Nat Commun ; 8(1): 1999, 2017 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-29222446

RESUMEN

Dielectric capacitors have the highest charge/discharge speed among all electrical energy devices, but lag behind in energy density. Here we report dielectric ultracapacitors based on ferroelectric films of Ba(Zr0.2,Ti0.8)O3 which display high-energy densities (up to 166 J cm-3) and efficiencies (up to 96%). Different from a typical ferroelectric whose electric polarization is easily saturated, these Ba(Zr0.2,Ti0.8)O3 films display a much delayed saturation of the electric polarization, which increases continuously from nearly zero at remnant in a multipolar state, to a large value under the maximum electric field, leading to drastically improved recyclable energy densities. This is achieved by the creation of an adaptive nano-domain structure in these perovskite films via phase engineering and strain tuning. The lead-free Ba(Zr0.2,Ti0.8)O3 films also show excellent dielectric and energy storage performance over a broad frequency and temperature range. These findings may enable broader applications of dielectric capacitors in energy storage, conditioning, and conversion.

6.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 23(12): 922-5, 2003 Dec.
Artículo en Zh | MEDLINE | ID: mdl-14714366

RESUMEN

OBJECTIVE: To observe the anti-liver-fibrosis effect of Guzhang Tablet (GZT) and to explore its mechanism. METHODS: Fifty female rats, weighing 200-220 g were randomly divided into the blank control group, the model group, the small dosage GZT group, the large dosage GZT group and the Biejiajian Pill (BJJP) group, 10 rats in each group. The changes of related serum enzymes, liver-fibrosis marker, oxygen free radical and liver tissue pathology were observed after 8 weeks of treatment. RESULTS: (1) Compared with the model group, the serum levels of alanine transaminase (ALT), aspartate aminotransferase (AST), glutamyltranspetidase (GGT), alkaline phosphatase (AKP) were improved in the GZT groups, better effect was got in the large dosage GZT group. (2) Compared with the blank control group, GZT showed no effect on serum total protein (TP) but with raising albumin (ALB) effect. (3) Compared with blank control group, the levels of hyaluronidase (HA), laminin (LN), collagen type IV (IV-C) and procollagen type III (PC III) in both GZT groups were lower, especially in the large dosage GZT group. (4) Small and large dosage of GZT showed effect in reducing malonyldialdehyde (MDA), Glutathione-peroxidose(GSH-Px) and nitric oxide (NO) content, but the effect on increasing superoxide dismutase (SOD) similar to that of BJJP with no significant different. (5) GZT, both small and large dosage, had obvious anti-liver fibrosis action, which was superior to that of BJJP. CONCLUSION: In the genetic and developing processes of liver fibrosis in rats, GZT could protect the liver cells, inhibit the synthesis and reduce the content of collagens, the mechanism might be related with its action in antagonizing peroxidation injury, indicating that GZT could effectively prevent liver fibrosis formation.


Asunto(s)
Colágeno Tipo III/sangre , Colágeno Tipo IV/sangre , Medicamentos Herbarios Chinos/farmacología , Cirrosis Hepática/patología , Animales , Medicamentos Herbarios Chinos/uso terapéutico , Hialuronoglucosaminidasa/sangre , Laminina/sangre , Cirrosis Hepática/sangre , Cirrosis Hepática/prevención & control , Masculino , Distribución Aleatoria , Ratas , Ratas Wistar , Comprimidos
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