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1.
Nanoscale ; 16(5): 2531-2539, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38214097

RESUMO

High-capacity anodes, especially silicon, suffer from huge volume fluctuations and electrode material pulverization during lithiation/delithiation. An accessible solution to this issue is to construct nano-silicon anodes with optimized particle size and a conductive matrix. In this work, we introduce a novel strategy for the in situ, rapid synthesis of ultra-small silicon nanoparticles uniformly embedded within carbonized nanosheets (us-Si/C) through swift high-temperature thermal radiative heating of sizable silicon nanoparticles (SiNPs). The us-Si/C anode shows ample capability to accommodate volume fluctuations during the lithiation/delithiation processes. The as-prepared anode exhibits a specific capacity of 920 mA h g-1 after 1000 cycles at a current density of 2 A g-1, indicating the advantages of the well-tailored structure. Additionally, the us-Si/C electrode can maintain an areal capacity of approximately 1.55 mA h cm-2 after 200 cycles at a high loading of 3.66 mg cm-2. Moreover, it presents practical applicability when assembled into LFP (lithium iron phosphate)//us-Si/C full cells. This preparation method presents great promise for achieving roll-to-roll manufacturing for practical applications due to its simplicity and efficiency.

2.
J Hazard Mater ; 443(Pt A): 130156, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36252406

RESUMO

Formaldehyde scavenger microcapsules were introduced into particleboard to prepare an ecofriendly particleboard with a low pollution release in response to the problem of long-term unstable free formaldehyde release from particleboards. By analyzing key parameters of formaldehyde emission from particleboard, the effects of microcapsules on the diffusion, migration and inhibition of free formaldehyde in particleboard pore structures was discussed. The results showed that microencapsulated formaldehyde scavenger prepared by an emulsification cross-linking method with chitosan as the wall material and urea as the core material resulted in a good long-term controlled release effect on formaldehyde emission. Compared with that of the control panel, the formaldehyde emission of the particleboard with microcapsules decreased by 51.4 % and 25.8 % at 28 d and 180 d, respectively. The addition of formaldehyde scavenger microcapsules increased the particleboard macroscopic pore volume, which facilitated the conversion of adsorbed formaldehyde into free formaldehyde in the pore structure, thereby promoting its migration and diffusion in the particleboard pores. Moreover, the synergistic effect of the addition-condensation and nucleophilic cross-linking of the core and wall materials quickly captured the free formaldehyde in the panels and reduced the releasable concentration of formaldehyde in the material, thus achieving the long-term effective control of formaldehyde emission.


Assuntos
Formaldeído , Substâncias Perigosas , Cápsulas , Formaldeído/química , Ureia
3.
Carbohydr Polym ; 277: 118872, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34893277

RESUMO

The use of ion-conductive hydrogels in strain sensors with high mechanical properties, conductivity, and anti-freezing properties is challenging. Here, high-strength, transparent, conductive, and anti-freezing organohydrogels were fabricated through the radical polymerization of polyacrylamide (PAM)/sodium alginate (SA)/TEMPO-oxidized cellulose nanofibrils (TOCNs) in a dimethyl sulfoxide (DMSO)/water solution, followed by soaking in a CaCl2 solution. The resulting organohydrogels demonstrated a high strength (tensile strength of 1.04 MPa), stretchability (681%), transparency (>84% transmittance), and ionic conductivity (1.25 S m-1). The organohydrogel-based strain sensor showed a high strain sensitivity (GF = 2.1). In addition, due to a synergistic effect between the DMSO/H2O binary solvent and CaCl2, the organohydrogel remained flexible (could bend 180°) and conductive (1.01 S m-1) at -20 °C. Interestingly, the TOCNs exerted a reinforcing effect on both the mechanical properties and ionic conductivity. This research provides a novel strategy to prepare ion-conductive organohydrogels with good mechanical properties, conductivity, and anti-freezing properties for use as flexible electronic materials.


Assuntos
Celulose/química , Congelamento , Hidrogéis/química , Nanopartículas/química , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Técnicas Eletroquímicas , Resistência à Tração
4.
Polymers (Basel) ; 11(1)2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30960170

RESUMO

This paper designed and manufactured photosensitive resin-based 2-D lattice structures with different types of variable cross-section cores by stereolithography 3D printing technology (SLA 3DP). An analytical model was employed to predict the structural compressive response and failure types. A theoretical calculation was performed to obtain the most efficient material utilization of the 2-D lattice core. A flatwise compressive experiment was performed to verify the theoretical conclusions. A comparison of theoretical and experimental results showed good agreement for structural compressive response. Results from the analytical model and experiments showed that when the 2-D lattice core was designed so that R/r = 1.167 (R and r represent the core radius at the ends and in the middle), the material utilization of the 2-D lattice core improved by 13.227%, 19.068%, and 22.143% when n = 1, n = 2, and n = 3 (n represents the highest power of the core cross-section function).

5.
Carbohydr Polym ; 203: 167-175, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30318200

RESUMO

A facile and robust strategy is required to fabricate films with highly photoluminescent for application in the field of anti-counterfeit marking. Here we report a kind of multifunctional bio-nanocomposite film with CdTe quantum dots (QDs) decorated with cellulose nanofibrils (CNFs). In this work, CNFs were introduced as nanothin film matrix, and crosslinking modification with EDC/NHS through covalent binding was used to introduce the CdTe QDs to prepare the nanoscale TEMPO-CNF/CdTe QDs nanocomposite material with uniform distribution, controllable particle size and good photoelectric properties. The TEMPO-CNF/CdTe QDs films displayed high optical transmittance (>80%) over the entire range of visible light, high quantum yield (36.9%), large tensile strength (110.0 MPa) and good hydrophilicity (contact angles of approximately 30°). These results indicated that functional TEMPO-CNF/CdTe films material with the colorimetric identification and photoluminescence was constructed and successfully applied to the "Green" anti-counterfeit marking.

6.
Materials (Basel) ; 11(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567336

RESUMO

In this study, 11 kinds of composite material were prepared, and the compression behavior of a bi-directional corrugated lattice sandwich structure prepared using jute fiber and epoxy resin was explored. The factors affecting the mechanical behavior of single and double-layer structures were studied separately. The results shows that the fiber angle, length-to-diameter ratio of the struts, and the type of fiber cloth have the most significant influence on the mechanical behavior of the single-layer lattice structure when preparing the core layer. When the fiber angle of the core layer jute/epoxy prepreg is (90/90) the compressive strength and Young's modulus are 83.3% and 60.0% higher than the fiber angle of (45/45). The configuration of the core and the presence of the intermediate support plate of the double-layer structure have a large influence on the compression performance of the two-layer structure. After the configuration was optimized, the compressive strength and Young's modulus were increased by 40.0% and 28.9%, respectively. The presence of the intermediate support plate increases the compressive strength, and Young's modulus of the double-layer structure by 75.0% and 26.6%, respectively. The experimental failure is dominated by the buckling, fracture, and delamination of the core struts.

7.
Bioresour Technol ; 249: 969-975, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29145124

RESUMO

The exploration of effective deconstruction of biomass complex structures and mild fractionation into individual components is a profound challenge for the development of biorefinery. Herein, a biomass fractionation process, via treating biomass in various aqueous alcohol solutions with the catalysis of acidic ionic liquids 1-butyl-3-methylimidazolium hydrogen sulfate, was demonstrated to fractionate coir and poplar into cellulose materials with a lignin content as low as 0.95% and lignin with a delignification rate of up to 98%. The participation of acidic ionic liquids into the solvent system greatly multiplied the biomass fractionation efficiency. The analysis on effects of the chemical structure and solubility parameter of alcohols on the delignification efficiency provided a rational and meaningful way to predict and screen solvent for the biomass fractionation process. Lignin in the present study exhibited similar structure with milled wood lignin, and comparable molecular and thermal properties with the conventional organosolv lignin.


Assuntos
Imidazóis , Solventes , Biomassa , Catálise , Líquidos Iônicos , Lignina
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