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1.
Molecules ; 28(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985453

RESUMO

With the increasing pollution of electromagnetic (EM) radiation, it is necessary to develop low-cost, renewable electromagnetic interference (EMI) shielding materials. Herein, wood-derived carbon (WC) materials for EMI shielding are prepared by one-step carbonization of renewable wood. With the increase in carbonization temperature, the conductivity and EMI performance of WC increase gradually. At the same carbonization temperature, the denser WC has better conductivity and higher EMI performance. In addition, due to the layered superimposed conductive channel structure, the WC in the vertical-section shows better EMI shielding performance than that in the cross-section. After excluding the influence of thickness and density, the specific EMI shielding effectiveness (SSE/t) value can be calculated to further optimize tree species. We further discuss the mechanism of the influence of the microstructure of WC on its EMI shielding properties. In addition, the lightweight WC EMI material also has good hydrophobicity and heat insulation properties, as well as good mechanical properties.

2.
Molecules ; 28(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36838820

RESUMO

Self-supporting electrode materials with the advantages of a simple operation process and the avoidance of the use any binders are promising candidates for supercapacitors. In this work, carbon-based self-supporting electrode materials with nanosheets grown on Al foil were prepared by combining hydrothermal reaction and the one-step chemical vapor deposition method. The effect of the concentration of the reaction solution on the structures as well as the electrochemical performance of the prepared samples were studied. With the increase in concentration, the nanosheets of the samples became dense and compact. The CNS-120 obtained from a 120 mmol zinc nitrate aqueous solution exhibited excellent electrochemical performance. The CNS-120 displayed the highest areal capacitance of 6.82 mF cm-2 at the current density of 0.01 mA cm-2. Moreover, the CNS-120 exhibited outstanding rate performance with an areal capacitance of 3.07 mF cm-2 at 2 mA cm-2 and good cyclic stability with a capacitance retention of 96.35% after 5000 cycles. Besides, the CNS-120 possessed an energy density of 5.9 µWh cm-2 at a power density of 25 µW cm-2 and still achieved 0.3 µWh cm-2 at 4204 µW cm-2. This work provides simple methods to prepared carbon-based self-supporting materials with low-cost Al foil and demonstrates their potential for realistic application of supercapacitors.


Assuntos
Araceae , Carbono , Capacitância Elétrica , Eletrodos , Gases
3.
Small ; 17(35): e2102532, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34302441

RESUMO

For the proliferation of the supercapacitor technology, it is essential to attain superior areal and volumetric performance. Nevertheless, maintaining stable areal/volumetric capacitance and rate capability, especially for thick electrodes, remains a fundamental challenge. Here, for the first time, a rationally designed porous monolithic electrode is reported with high thickness of 800 µm (46.74 mg cm-2 , with high areal mass loading of NiCo2 S4 6.9 mg cm-2 ) in which redox-active Ag nanoparticles and NiCo2 S4 nanosheets are sequentially decorated on highly conductive wood-derived carbon (WC) substrates. The hierarchically assembled WC@Ag@NiCo2 S4 electrode exhibits outstanding areal capacitance of 6.09 F cm-2 and long-term stability of 84.5% up to 10 000 cycles, as well as exceptional rate capability at 50 mA cm-2 . The asymmetric cell with an anode of WC@Ag and a cathode of WC@Ag@NiCo2 S4 delivers areal/volumetric energy density of 0.59 mWh cm-2 /3.93 mWh cm-3 , which is much-improved performance compared to those of most reported thick electrodes at the same scale. Theoretical calculations verify that the enhanced performance could be attributed to the decreased adsorption energy of OH- and the down-shifted d-band of Ag atoms, which can accelerate the electron transport and ion transfer.

4.
Biochem Biophys Res Commun ; 503(4): 2429-2435, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-29969631

RESUMO

Recently, circular RNAs (circRNAs) attract much attention due to their potential vital functions in multiple human diseases, including cancer. circ-BANP has been reported to modulate colorectal cancer growth. Nevertheless, the relationship between circ-BANP and lung cancer requires to be investigated. In this study, we found circ-BANP was overexpressed in lung cancer tissues. Higher circ-BANP expression was associated with lower survival rate. Moreover, silencing circ-BANP markedly inhibited proliferation, migration and invasion of lung cancer cells in vitro and impaired tumor propagation in vivo. In mechanism, circ-BANP was identified as the sponge of miR-503 while miR-503 targets LARP1. Circ-BANP-induced inhibition of miR-503 led to increased expression of LARP1 in lung cancer. Finally, rescue assays indicated that LARP1 restoration partially reversed the effects of circ-BANP knockdown in lung cancer. In sum, our study illustrated that circ-BANP-mediated miR-503/LARP1 signaling promoted lung cancer growth, migration and invasion, providing a novel insight on the mechanism underlying lung cancer progression.


Assuntos
Autoantígenos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , Invasividade Neoplásica/genética , RNA/genética , Ribonucleoproteínas/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Nus , Invasividade Neoplásica/patologia , RNA Circular , Transdução de Sinais , Antígeno SS-B
5.
Artigo em Inglês | MEDLINE | ID: mdl-29553919

RESUMO

Experiments were carried out to test the capacity for a laboratory-scale biofilter operated at an elevated temperature level (∼50°C) to remove an air stream containing ß-caryophyllene, a naturally occurring sesquiterpene of environmental concern emitted from wood-related industrial facilities. A water jacket was used to maintain high temperatures in a laboratory-scale biofilter. Inocula, pollutant loading and nutrient supply rate effects were evaluated over 84 days of biofilter operation. The start-up process took over two months when citrus peels were used as inocula while a relatively short start-up period was achieved after introducing forest compost products. While using a sparged-gas bioreactor to cultivate an enrichment culture for 97 days, removal efficiencies in excess of 80% were observed after 18 days. At empty bed contact times of 50 s and at a pollutant loading rate of 3.05 mg C/L/hr, removal efficiency levels reached 90% and the elimination capacity level reached 2.29 mg C/L/hr, corresponding to an elimination capacity of 2.60 mg ß-caryophyllene/L/hr. Collectively, these results demonstrate that ß-caryophyllene can be successfully removed from contaminated air using a biofilter operated at a high temperature (∼50°C), expanding the temperature range within which biofilters are known to biodegrade sesquiterpenes.


Assuntos
Filtração/métodos , Gases/isolamento & purificação , Temperatura Alta , Sesquiterpenos/isolamento & purificação , Poluição do Ar/prevenção & controle , Biodegradação Ambiental , Reatores Biológicos , Citrus/química , Filtração/instrumentação , Gases/química , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Temperatura , Madeira/química
6.
Tumour Biol ; 36(5): 3693-701, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25725584

RESUMO

Recent studies have implied that aberration of miR-24 is linked to various human cancers. However, its role in non-small cell lung cancer (NSCLC) remains obscure. Here, we found that miR-24 was significantly upregulated in NSCLC tissues and patients' serum. High expression of miR-24 in patients' serum was independently correlated with a shorter overall survival of NSCLC patients. Depletion of miR-24 inhibited cell proliferation and anchorage-independent survival ability in lung cancer cell lines and reduced tumor formation ability in nude mice. Nuclear apoptosis-inducing factor 1 (NAIF1) was identified to be a functional target of miR-24 in the human lung. Next, we observed that the NAIF1 mRNA expression level in NSCLC tissues was suppressed in comparison to that in adjacent normal tissues. Restoration of NAIF1 in lung cancer cell inhibited cell proliferation and anchorage-independent survival ability, which were found to be similar with those from transfecting a miR-24 inhibitor into lung cancer cells. In conclusion, our study demonstrated that miR-24 was upregulated in NSCLC, and suppressing the expression of miR-24 inhibited tumor characteristics. MiR-24 acted as an oncomir, at least partially through regulation of its functional target NAIF1 in NSCLC. MiR-24 may serve as a novel potential biomarker for NSCLC diagnosis and prognosis.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células , Neoplasias Pulmonares/patologia , MicroRNAs/fisiologia , Proteínas Nucleares/genética , Adulto , Idoso , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Camundongos , MicroRNAs/sangue , Pessoa de Meia-Idade , Regulação para Cima
7.
Artigo em Inglês | MEDLINE | ID: mdl-38839349

RESUMO

T-tubes and airway stents are commonly used but have limited effectiveness and frequent complications. A 50-year-old male patient presented with severe tracheal stenosis, affecting an 8.7 cm length of the airway. We employed an innovative approach known as external suspension fixation of tracheal stent using robotic assistance. This method involves surgically attaching the stent to the exterior of the trachea to provide support and stabilize the softened or collapsed tracheal segments. We designed a C-shaped nickel-titanium alloy exterior stent and successfully fixed it using robotic assistance. This intervention effectively restored tracheal function and led to a favorable postoperative recovery. The technique does not affect tracheal membrane function or airway mucociliary clearance. It could potentially be considered as a new option for treating long-segment benign tracheal softening or collapse.


Assuntos
Níquel , Desenho de Prótese , Procedimentos Cirúrgicos Robóticos , Stents , Titânio , Estenose Traqueal , Humanos , Masculino , Pessoa de Meia-Idade , Estenose Traqueal/cirurgia , Estenose Traqueal/diagnóstico por imagem , Estenose Traqueal/etiologia , Estenose Traqueal/fisiopatologia , Resultado do Tratamento , Ligas
8.
Int J Biol Macromol ; 259(Pt 2): 129268, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199536

RESUMO

With the rapid development of the Internet of Things, nanogenerator as a green energy collection technology has attracted great attention in various fields. Specifically, the natural renewable nanocellulose as a raw material can significantly improve the environmental friendliness of the nanocellulose-based nanogenerators, which also makes the nanocellulose based nanogenerators expected to further develop in areas such as wearable devices and sensor networks. This paper mainly reports the application of nanocellulose in nanogenerator, focusing on the sensor. The types, sources and preparation methods of nanocellulose are briefly introduced. At the same time, the special structure of nanocellulose highlights the advantages of nanocellulose in nanogenerators. Then, the application of nanocellulose-based nanogenerators in sensors is introduced. Finally, the future development prospects and shortcomings of this nanogenerator are discussed.


Assuntos
Internet , Dispositivos Eletrônicos Vestíveis , Tecnologia
9.
Carbohydr Polym ; 333: 121947, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494214

RESUMO

The rapid development of hydrogels has garnered significant attention in health monitoring and human motion sensing. However, the synthesis of multifunctional conductive hydrogels with excellent strain/pressure sensing and photoresponsiveness remains a challenge. Herein, the conductive hydrogels (BPTP) with excellent mechanical properties, fatigue resistance and photoresponsive behavior composed of polyacrylamide (PAM) matrix, 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) reinforcement and polydopamine-modified black phosphorus (BP@PDA) photosensitizer are prepared through a facile free-radical polymerization approach. The PDA adhered to the BP surface by π-π stacking promotes the optical properties of BP while also preventing BP oxidation from water. Through hydrogen bonding interactions, TOCNs improve the homogeneous dispersion of BP@PDA nanosheets and the mechanical toughness of BPTP. Benefiting from the synergistic effect of PDA and TOCNs, the conductive BPTP integrates superior mechanical performances, excellent photoelectric response and photothermal conversion capability. The BPTP-based sensor with high cycling stability demonstrates superior strain sensitivity (GF = 6.0) and pressure sensing capability (S = 0.13 kPa-1) to monitor various human activities. Therefore, this work delivers an alternative construction strategy for generating high-performance conductive hydrogels as multifunctional wearable sensors.


Assuntos
Celulose Oxidada , Dispositivos Eletrônicos Vestíveis , Humanos , Condutividade Elétrica , Hidrogéis , Ligação de Hidrogênio
10.
J Colloid Interface Sci ; 660: 923-933, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280285

RESUMO

The flexible and self-healing supercapacitors (SCs) are considered to be promising smart energy storage devices. Nevertheless, the SCs integrated with flexibility, lightweight, pattern editability, self-healing capabilities and desirable electrochemical properties remain a challenge. Herein, an all-in-one self-healing SC fabricated with the free-standing hybrid film (TCMP) composed of the 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) carried carbon nanotubes (CNTs), manganese dioxide (MnO2) and polyaniline (PANI) as the electrode, polyvinyl alcohol/sulfuric acid (PVA/H2SO4) gel as the electrolyte and dynamically cross-linked cellulose nanofibers/PVA/sodium tetraborate decahydrate (CNF/PB) hydrogel as the self-healing electrode matrix is developed. The TCMP film electrodes are fabricated through a facile in-situ polymerization of MnO2 and PANI in TOCNs-dispersed CNTs composite networks, exhibiting lightweight, high electrical conductivity, flexibility, pattern editability and excellent electrochemical properties. Benefited from the hierarchically porous structure and high mechanical properties of TOCNs, excellent electrical conductivity of CNTs and the desirable synergistic effect of pseudocapacitance induced by MnO2 and PANI, the assembled SC with an interdigital structure demonstrated a high areal capacitance of 1108 mF cm-2 at 2 mA cm-2, large areal energy density of 153.7 µWh cm-2 at 1101.7 µW cm-2. A satisfactory bending cycle performance (capacitance retention up to 95 % after 200 bending deformations) and self-healing characteristics (∼90 % capacitance retention after 10 cut/repair cycles) are demonstrated for the TCMP-based symmetric SC, delivering a feasible strategy for electrochemical energy storage devices with excellent performance, designable patterns and desirable safe lifespan.

11.
Carbohydr Polym ; 330: 121822, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38368103

RESUMO

Hydroxypropyl cellulose (HPC) is a sustainable cellulose derivative valued for its excellent biocompatibility and solubility and is widely used in various fields. Recent scientific research on high-substituted HPC mainly focused on its efficient preparation and phase transition behavior. Herein, a novel strategy of high-substituted HPC synthesis was demonstrated by employing DMSO/TBAF·3H2O as a cellulose solvent, exhibiting more efficiency than traditional approaches. High-substituted HPC prepared has remarkable thermal stability, exceptional hydrophilicity, and satisfactory solubility. Phase transition behavior of HPC with varying molar degrees of substitution (MS) was delved and a notable negative correlation between MS and cloud point temperature (TCP), was revealed, particularly evident at an MS of 12.3, where the TCP drops to 33 °C. Moreover, a unique self-assembly behavior featuring structural color and responsiveness to force in a solvent-free environment emerged when the MS exceeded 10.4. These insights comprehensively strengthen the understanding and knowledge of high-substituted HPC, simultaneously paving the way for further HPC investigation and exploitation.

12.
Carbohydr Polym ; 335: 122067, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616090

RESUMO

Inspired by creatures, abundant stimulus-responsive hydrogel actuators with diverse functionalities have been manufactured for applications in soft robotics. However, constructing a shape memory and self-sensing bilayer hydrogel actuator with high mechanical strength and strong interfacial bonding still remains a challenge. Herein, a novel bilayer hydrogel with a stimulus-responsive TEMPO-oxidized cellulose nanofibers/poly(N-isopropylacrylamide) (TOCN/PNIPAM) layer and a non-responsive TOCN/polyacrylamide (TOCN/PAM) layer is proposed as a thermosensitive actuator. TOCNs as a nano-reinforced phase provide a high mechanical strength and endow the hydrogel actuator with a strong interfacial bonding. Due to the incorporation of TOCNs, the TOCN/PNIPAM hydrogel exhibits a high compressive strength (~89.2 kPa), elongation at break (~170.7 %) and tensile strength (~24.0 kPa). The prepared PNIPAM/TOCN/PAM hydrogel actuator performs the roles of an encapsulation, jack, temperature-controlled fluid valve and temperature-control manipulator. The incorporation of Fe3+ further endows the bilayer hydrogel actuator with a synergistic performance of shape memory and temperature-driven, which can be used as a temperature-responsive switch to detect ambient temperature. The PNIPAM/TOCN/PAM-Fe3+ conductive hydrogel can be assembled into a flexible sensor and generate sensing signals when driven by temperature changes to achieve real-time feedback. This research may lead to new insights into the design and manufacturing of intelligent flexible soft robots.

13.
Int J Biol Macromol ; 266(Pt 2): 131080, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537850

RESUMO

Despite the tremendous efforts on developing antibacterial wearable textile materials containing Ti3C2Tx MXene, the singular antimicrobial mechanism, poor antibacterial durability, and oxidation susceptibility of MXene limits their applications. In this context, flexible multifunctional cellulosic textiles were prepared via layer-by-layer assembly of MXene and the in-situ synthesis of zeolitic imidazolate framework-8 (ZIF-8). Specifically, the introduction of highly conductive MXene enhanced the interface interactions between the ZIF-8 layer and cellulose fibers, endowing the green-based materials with outstanding synergistic photothermal/photodynamic therapy (PTT/PDT) activity and adjustable electromagnetic interference (EMI) shielding performance. In-situ polymerization formed a MXene/ZIF-8 bilayer structure, promoting the generation of reactive oxygen species (ROS) while protecting MXene from oxidation. The as-prepared smart textile exhibited excellent bactericidal efficacy of >99.99 % against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) after 5 min of NIR (300 mW cm-2) irradiation which is below the maximum permissible exposure (MPE) limit. The sustained released Zn2+ from the ZIF-8 layer achieved a bactericidal efficiency of over 99.99 % within 48 h without NIR light. Furthermore, this smart textile also demonstrated remarkable EMI shielding efficiency (47.7 dB). Clearly, this study provides an elaborate strategy for designing and constructing multifunctional cellulose-based materials for a variety of applications.


Assuntos
Antibacterianos , Celulose , Escherichia coli , Imidazóis , Estruturas Metalorgânicas , Staphylococcus aureus , Têxteis , Celulose/química , Celulose/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Escherichia coli/efeitos dos fármacos , Zeolitas/química , Zeolitas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Testes de Sensibilidade Microbiana , Fotoquimioterapia/métodos
14.
Biomacromolecules ; 14(5): 1529-40, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23544667

RESUMO

Cellulose nanocrystals and cellulose nanofibers with I and II crystalline allomorphs (designated as CNC I, CNC II, CNF I, and CNF II) were isolated from bleached wood fibers by alkaline pretreatment and acid hydrolysis. The effects of concentration, particle size, surface charge, and crystal structure on the lyophilization-induced self-assembly of cellulose particles in aqueous suspensions were studied. Within the concentration range of 0.5 to 1.0 wt %, cellulose particles self-organized into lamellar structured foam composed of aligned membrane layers with widths between 0.5 and 3 µm. At 0.05 wt %, CNC I, CNF I, CNC II, and CNF II self-assembled into oriented ultrafine fibers with mean diameters of 0.57, 1.02, 1.50, and 1.00 µm, respectively. The size of self-assembled fibers became larger when more hydroxyl groups and fewer sulfates (weaker electrostatic repulsion) were on cellulose surfaces. Possible formation mechanism was inferred from ice growth and interaction between cellulose nanoparticles in liquid-crystalline suspensions.


Assuntos
Celulose/química , Nanofibras/química , Nanopartículas/química , Água/química , Celulose/isolamento & purificação , Liofilização , Hidrólise , Microscopia Eletrônica de Transmissão , Nanofibras/ultraestrutura , Nanopartículas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática , Propriedades de Superfície , Suspensões , Madeira/química
15.
Int J Med Robot ; 19(3): e2507, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36763095

RESUMO

INTRODUCTION: Robotic-assisted thoracic surgery (RATS) via subxiphoid incision may be superior in resection of multiple lung nodules. METHODS: Outcomes of robot-assisted one-stage bilateral lobectomy or segmentectomy via intercostal and subxiphoid incisions for multiple ground-glass opacities were analysed. RESULTS: Total 36 cases were analysed in this study. Thirteen cases had bilateral lobectomy + segmentectomy, 15 cases underwent bilateral segmentectomies, and 8 cases underwent lobectomy + segmentectomy + wedge resection. The average intraoperative blood loss was 110.2 ± 57.8 mL, operation time was 154 ± 64.2 min, thoracic draining time was 2.6 ± 3.2 days, and postoperative hospital stay was 4.8 ± 3.3 days. Three patients had atrial fibrillation and 3 patients had continuous air leakage for over 3 days, but there was no death or postoperative pain. CONCLUSION: Robot-assisted one-stage bilateral resection of multiple lung nodules through combination of intercostal and subxiphoid incision as a utility port is safe and reliable.


Assuntos
Neoplasias Pulmonares , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Neoplasias Pulmonares/cirurgia , Estudos Retrospectivos , Pulmão/cirurgia , Cirurgia Torácica Vídeoassistida
16.
Int J Biol Macromol ; 224: 1236-1243, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36550788

RESUMO

In order to reduce the dependence on fossil energy products, natural fiber/polymer hybrid composites have been increasingly researched. The high price of the quartz optical fibers and glass optical fibers has greatly inspired researchers to engage in the research on polymer optical fibers. Herein, transparent fibers based on plant fibers were innovatively prepared for the first time by delignification and impregnating epoxy diluted with acetone. The epoxy improved the thermal stability of the fiber without deteriorating its mechanical properties, and also endowed the fiber with the property of transparency. The tensile strength of transparent fibers of three diameters were 34.5, 58.6 and 100.3 MPa, respectively and the corresponding Young's modulus reached 1.1, 1.7 and 2.3 GPa, respectively. In addition, the light-conducting properties of transparent fibers were displayed with a green laser and the fibers displayed good light transmission along the fiber growth direction. Transparent fibers are expected to be used in optical fibers because of their high thermal stability, good mechanical properties and light-conducting properties.


Assuntos
Fibras Ópticas , Polímeros , Resistência à Tração
17.
ACS Appl Mater Interfaces ; 15(3): 4358-4370, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36622958

RESUMO

Biologically inspired superstructural materials exhibit wide application prospects in many fields, in terms of mitigating increasingly serious electromagnetic (EM) pollution in the civil field. Here, we successfully obtain bamboo slices with uniform pore size distribution through the advanced bamboo transverse splitting technology developed by our group previously and prepare large-scale honeycomb-like carbon-based tubular array (CTA) structures with a controllable pore size, graphitization degree, and selectable conductivity property. Based on the simulation and experimental results, the EM shielding performance of CTAs is proven to be sensitive to the microchannel aperture size and the EM energy incident angle, which is attributed to the difference in the propagation rate of induced electrons in different directions. Among the candidates, CTA-middle-1500 exhibits the best shielding performance against incident EM energy with average SE/ρ values of 123.7 and 144.5 dB cm3 g-1 for perpendicular and parallel directions, respectively, showing its application potential as a lightweight and efficient EM shielding material. The predicted optimal incident angle for CTA-middle-1500 against EM energy radiation is 15°, with the largest RCS reduction value of 26.1 dB m2. The excellent EM shielding performance is attributed to the good reflection capacity involved with the high conductivities of the CTAs.

18.
ACS Nano ; 17(10): 8866-8898, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37126761

RESUMO

The emergence and development of thick electrodes provide an efficient way for the high-energy-density supercapacitor design. Wood is a kind of biomass material with porous hierarchical structure, which has the characteristics of a straight channel, uniform pore structure, good mechanical strength, and easy processing. The wood-inspired low-tortuosity and vertically aligned channel architecture are highly suitable for the construction of thick electrochemical supcapacitor electrodes with high energy densities. This review summarizes the design concepts and processing parameters of thick electrode supercapacitors inspired by natural woods, including wood-based pore structural design regulation, electric double layer capacitances (EDLCs)/pseudocapacitance construction, and electrical conductivity optimization. In addition, the optimization strategies for preparing thick electrodes with wood-like structures (e.g., 3D printing, freeze-drying, and aligned-low tortuosity channels) are also discussed in detail. Further, this review presents current challenges and future trends in the design of thick electrodes for supercapacitors with wood-inspired pore structures. As a guideline, the brilliant blueprint optimization will promote sustainable development of wood-inspired structure design for thick electrodes and broaden the application scopes.

19.
ACS Appl Mater Interfaces ; 14(21): 24708-24719, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594189

RESUMO

A nanofiltration (NF) membrane containing a NaOH-treated electrospun polyacrylonitrile (HPAN) substrate, an interfacial polymerization (IP) polyamide (PA) layer, a chitosan (CS) coating layer, and an Ag/AgBr/AgVO3 photocatalyst loading layer was prepared. The structural evolution of the membranes was investigated, and their performance was estimated in accordance with the water flux and rejection rate. A probable mechanism for the photocatalytic activity of Ag/AgBr/AgVO3 was proposed. The loading of the Ag/AgBr/AgVO3 heterojunction on the HPAN/PA/CS NF membrane endowed the membrane with excellent self-cleaning properties owing to the photolytic degradation of the dye. The filtration and degradation processes of the Ag/AgBr/AgVO3-loaded membrane constantly promoted each other, and the treatment efficiency achieved with the integrated (filtration + degradation) process was superior to those obtained with the filtration and degradation processes alone. The Ag/AgBr/AgVO3-NF membrane exhibited excellent recyclability and stability when subjected to five integrated filtration-degradation processes. In addition, the Ag/AgBr/AgVO3-NF membrane exhibited an elastic modulus of 65.75 MPa and a toughness of 38.9 kJ/m3 along with a good disinfection effect on Escherichia coli in visible light. The as-prepared photocatalyst-loaded NF membrane with excellent antifouling performance, antimicrobial activity, high strength, and recyclability showed potential for continuous water purification operation.

20.
Carbohydr Polym ; 298: 120075, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241270

RESUMO

Holocellulose nanofibrils (HCNFs) are nanoscale objects extracted from biomass resources and have attracted attention as sustainable building blocks for nanomaterials. In this study, we report a top-down approach for extracting HCNFs from manau rattan that involves pulping, bleaching and TEMPO oxidation. The extracted HCNFs showed a uniform width of around 18.5 nm and a length of a few micrometers, high crystallinity (66.5 %), and good thermal stability (302 °C). The extracted HCNFs were used to fabricate HCNF film via vacuum filtration and drying (air drying and solvent exchange drying). Surprisingly, the HCNF film fabricated by solvent exchange drying (HCNF-filmSD) simultaneously presented a high total transmittance (93.7 %) and high haze (62.2 %), and its total transmittance was even higher than that of glass. The resulting HCNF-filmSD displayed a high tensile strength (84.8 MPa), Young's modulus (3.7 GPa), and toughness (1.4 MJ m-3), making it a high-performance and eco-friendly film for applications in precision optoelectronics and aerospace materials.


Assuntos
Celulose , Nanoestruturas , Módulo de Elasticidade , Solventes , Resistência à Tração
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