Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Small ; 19(40): e2302686, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37208798

RESUMEN

Developing carbon encapsulated magnetic composites with rational design of microstructure for achieving high-performance electromagnetic wave (EMW) absorption in a facile, sustainable, and energy-efficiency approach is highly demanded yet remains challenging. Here, a type of N-doped carbon nanotube (CNT) encapsulated CoNi alloy nanocomposites with diverse heterostructures are synthesized via the facile, sustainable autocatalytic pyrolysis of porous CoNi-layered double hydroxide/melamine. Specifically, the formation mechanism of the encapsulated structure and the effects of heterogenous microstructure and composition on the EMW absorption performance are ascertained. With the presence of melamine, CoNi alloy emerges its autocatalysis effect to generate N-doped CNTs, leading to unique heterostructure and high oxidation stability. The abundant heterogeneous interfaces induce strong interfacial polarization to EMWs and optimize impedance matching characteristic. Combined with the inherent high conductive and magnetic loss capabilities, the nanocomposites accomplish a high-efficiency EMW absorption performance even at a low filling ratio. The minimum reflection loss of -84.0 dB at the thickness of 3.2 mm and a maximum effective bandwidth of 4.3 GHz are obtained, comparable to the best EMW absorbers. Integrated with the facile, controllable, and sustainable preparation approach of the heterogenous nanocomposites, the work shows a great promise of the nanocarbon encapsulation protocol for achieving lightweight, high-performance EMW absorption materials.

2.
Small ; 18(24): e2202047, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35570715

RESUMEN

Ultralight and highly flexible aerogel sensors, composed of reduced graphene oxide cross-linked by sustainable-macromolecule-derived carbon, are prepared via facile freeze-drying and thermal annealing. The synergistic combination of cross-linked graphene nanosheets and micrometer-sized honeycomb pores gives rise to the exceptional properties of the aerogels, including superior compressibility and resilience, good mechanical strength and durability, satisfactory fire-resistance, and outstanding electromechanical sensing performances. The corresponding aerogel sensors, operated at an ultralow voltage of 0.2 V, can efficiently respond to a wide range of strains (0.1-80%) and pressures (13-2750 Pa) even at temperatures beyond 300 °C. Moreover, the ultrahigh-pressure sensitivity of 10 kPa-1 and excellent sensing stability and durability are accomplished. Strikingly, the aerogel sensors can also sense the vibration signals with ultrahigh frequencies of up to 4000 Hz for >1 000 000 cycles, significantly outperforming those of other sensors. These enable successful demonstration of the exceptional performance of the cross-linked graphene-based biomimetic aerogels for sensitive monitoring of mechanical signals, e.g., acting as wearable devices for monitoring human motions, and for nondestructive monitoring of cracks on engineering structures, showing the great potential of the aerogel sensors as next-generation electronics.


Asunto(s)
Grafito , Dispositivos Electrónicos Vestibles , Carbono/química , Electrónica , Grafito/química , Humanos , Vibración
3.
Anal Chem ; 93(31): 10982-10989, 2021 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-34328720

RESUMEN

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a robust and powerful tool for studying biomacromolecules and their interactions. However, quantitative detection of high-mass analytes (kDa to MDa range) remains challenging for MALDI-MS. Herein, we successfully used commercially available purified proteins (ß-galactosidase and BSA) as internal standards for high-mass MALDI-MS analysis and achieved absolute quantification of several high-mass analytes. We systematically evaluated four sample deposition methods, and using the sandwich deposition method with saturated sinapinic acid as the top layer, we performed a robust quantitative analysis by high-mass MALDI-MS. Combined with chemical cross-linking, this quantitative strategy was further used to evaluate the affinity of protein-protein interactions (PPIs), specifically of two soluble protein receptors (interleukin 1 receptor and interleukin 2 receptor) and two membrane protein receptors (rhodopsin and angiotensin 2 receptor 1) with their interaction partners. The measured dissociation constants of the protein complexes formed were between 10 nM and 5 µM. We expect this high-throughput, rapid method, which does not require labeling or immobilization of any of the interaction partners, to become a viable alternative to traditional biophysical methods for studying PPIs.


Asunto(s)
Rayos Láser , Proteínas , Unión Proteica , Proteínas/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(2): 198-203, 2020 Feb 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-32386048

RESUMEN

Rubinstein-Taybi syndrome (RSTS), also known as broad thumb-great toe syndrome or broad digits syndrome, is a rare autosomal dominant genetic disease. The main features of the patients are craniofacial dysmorphisms, skeletal malformations, and delay of growth and psychomotor development. In this case, the child has a typical RSTS specific face and growth retardation, with atypical indirect inguinalhemia. A heterozygous mutation, C. 4492 C>T (p. Arg1498Ter), was found in the exon of CREBBP gene by gene sequencing. It was a nonsense mutation, which leads to the premature termination of peptide synthesis. The mutation was not observed in the child's parents, which may be a de Novo mutation. The disease is lack of effective therapy so far.


Asunto(s)
Proteína de Unión a CREB/genética , Síndrome de Rubinstein-Taybi , Codón sin Sentido , Exones , Humanos , Lactante , Mutación
5.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(1): 74-80, 2019 Jan 28.
Artículo en Zh | MEDLINE | ID: mdl-30837406

RESUMEN

In the development of oxidative stress-relevant diseases, reactive oxygen species (ROS) removal obstacle or excess production results in the damage of the body tissues and organs. Recent studies have demonstrated that nuclear factor E2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) axis played a significant role in anti-oxidative stress. The Nrf2/HO-1 axis counteracts oxidative stress injury by its resistance to inflammation, oxidation, mitochondrial damage and calcium influx, apoptosis, pyroptosis, ferroptosis and autophagy, which provides a theoretical basis for its therapeutic effect on various oxidative stress-relevant diseases in multiple organs (respiratory, cardiovascular, nervous, digestive, urinary and blood systems). Therefore, effective regulation of the Nrf2/HO-1 signal axis can be an important strategy for treatment of oxidative stress-relevant diseases.


Asunto(s)
Estrés Oxidativo , Hemo-Oxigenasa 1 , Factor 2 Relacionado con NF-E2 , Especies Reactivas de Oxígeno , Transducción de Señal
6.
Small ; 13(34)2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28696564

RESUMEN

Multiwalled carbon nanotube/polymer composites with aligned and isotropic micropores are constructed by a facile ice-templated freeze-drying method in a wide density range, with controllable types and contents of the nanoscale building blocks, in order to tune the shielding performance together with the considerable mechanical and electrical properties. Under the mutual promotion of the frame and porous structure, the lightweight high-performance shielding is achieved: a 2.3 mm thick sample can reach 46.7 and 21.7 dB in the microwave X-band while the density is merely 32.3 and 9.0 mg cm-3 , respectively. The lowest density corresponds to a value of shielding effectiveness divided by both the density and thickness up to 104 dB cm2 g-1 , far beyond the conductive polymer composites with other fillers ever reported. The shielding mechanism of the flexible porous materials is further demonstrated by an in situ compression experiment.

7.
Adv Sci (Weinh) ; 11(19): e2400403, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38483033

RESUMEN

Improving interface connectivity of magnetic nanoparticles in carbon aerogels is crucial, yet challenging for assembling lightweight, elastic, high-performance, and multifunctional carbon architectures. Here, an in situ growth strategy to achieve high dispersion of metal-organic frameworks (MOFs)-anchored cellulose nanofibrils to enhance the interface connection quality is proposed. Followed by a facile freeze-casting and carbonization treatment, sustainable biomimetic porous carbon aerogels with highly dispersed and closely connected MOF-derived magnetic nano-capsules are fabricated. Thanks to the tight interface bonding of nano-capsule microstructure, these aerogels showcase remarkable mechanical robustness and flexibility, tunable electrical conductivity and magnetization intensity, and excellent electromagnetic wave absorption performance. Achieving a reflection loss of -70.8 dB and a broadened effective absorption bandwidth of 6.0 GHz at a filling fraction of merely 2.2 wt.%, leading to a specific reflection loss of -1450 dB mm-1, surpassing all carbon-based aerogel absorbers so far reported. Meanwhile, the aerogel manifests high magnetic sensing sensibility and excellent thermal insulation. This work provides an extendable in situ growth strategy for synthesizing MOF-modified cellulose nanofibril structures, thereby promoting the development of high-value-added multifunctional magnetic carbon aerogels for applications in electromagnetic compatibility and protection, thermal management, diversified sensing, Internet of Things devices, and aerospace.

8.
Adv Mater ; 36(14): e2311135, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38146773

RESUMEN

Transition metal carbides/nitrides (MXenes) demonstrate a massive potential in constructing lightweight, multifunctional wearable electromagnetic interference (EMI) shields for application in various fields. Nevertheless, it remains challenging to develop a facile, scalable approach to prepare the MXene-based macrostructures characterized by low density, low thickness, high mechanical flexibility, and high EMI SE at the same time. Herein, the ultrathin MXene/reduced graphene oxide (rGO)/Ag foams with a porifera-inspired hierarchically porous microstructure are prepared by combining Zn2+ diffusion induction and hard template methods. The hierarchical porosity, which includes a mesoporous skeleton and a microporous MXene network within the skeleton, not only exerts a regulatory effect on stress distribution during compression, making the foams rubber-like resistant to wrinkling but also provides more channels for multiple reflections of electromagnetic waves. Due to the interaction between Ag nanosheets, MXene/rGO, and porous structure, it is possible to produce an outstanding EMI shielding performance with the specific surface shielding effectiveness reaching 109152.4 dB cm2 g-1. Furthermore, the foams exhibit multifunctionalities, such as transverse Joule heating, longitudinal heat insulation, self-cleaning, fire resistance, and motion detection. These discoveries open up a novel pathway for the development of lightweight MXene-based materials with considerable application potential in wearable electromagnetic anti-interference devices.

9.
Sci Adv ; 10(11): eadl6498, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38478599

RESUMEN

Designing a functional, conductive metal-organic framework (cMOF) is highly desired. Substantial efforts have been dedicated to increasing the intralayer conjugation of the cMOFs, while less dedication has been made to tuning the interlayer charge transport of the metal-organic nanosheets for the controllable dielectric property. Here, we construct a series of conductive bimetallic organic frameworks of (ZnxCu3-x) (hexahydroxytriphenylene)2 (ZnCu-HHTP) to allow for fine-tuned interlayer spacing of two-dimensional frameworks, by adjusting the ratios of Zn and Cu metal ions. This approach for atomistic interlayer design allows for the finely control of the charge transport, band structure, and dielectric properties of the cMOF. As a result, Zn3Cu1-HHTP, with an optimal dielectric property, exhibits high-efficiency absorption in the gigahertz microwave range, achieving an ultra-strong reflection loss of -81.62 decibels. This study not only advances the understanding of the microstructure-function relationships in cMOFs but also offers a generic nanotechnology-based approach to achieving controllable interlayer spacing in MOFs for the targeted applications.

10.
Medicine (Baltimore) ; 102(10): e33177, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36897722

RESUMEN

BACKGROUND: The aim of this systematic review and meta-analysis was to assess the relationship between H pylori infection and colorectal cancer risk in East Asian patients. METHODS: Two researchers independently searched for relevant studies in the PubMed, Cochrane, and Embase databases from inception up to April 2022. A meta-analysis was then performed to calculate pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) using a random effects model. RESULTS: Nine studies involving 6355 patients were included. Overall, we observed that H pylori infection was associated with an increased risk of colorectal cancer in East Asian patients (OR = 1.48, 95% CI: 1.10-1.99, I2 = 70%), although significant heterogeneity was identified among studies. Subgroup analysis revealed that H pylori infection was associated with an increased risk of colorectal cancer in China (OR = 1.58, 95% CI 1.05-2.37, I2 = 81%) but not in Japan and Korea (OR = 1.26, 95% CI 0.93-1.70, I2 = 0%). CONCLUSION: This meta-analysis identified a positive association between H pylori infection and colorectal cancer risk in East Asian patients, especially in China.


Asunto(s)
Neoplasias Colorrectales , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Pueblos del Este de Asia , Infecciones por Helicobacter/complicaciones , Riesgo , Neoplasias Colorrectales/complicaciones
11.
Gels ; 9(2)2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36826274

RESUMEN

Solving the problem of the low temperature and low salt resistances of conventional polyacrylamide and the high cost of functional monomers, and thus, introducing it to the interlayer space provided by a layered structure for polymer modification, is a promising option. In this study, montmorillonite was used as the inorganic clay mineral, and an intercalated polyacrylamide/clay nanocomposite was synthesized via in situ intercalation polymerization. The optimal synthesis conditions were a clay content of 10.7%, preparation temperature of 11 °C, initiator concentration of 2.5 × 10-4 mol/L, and chain extender concentration of 5%. The IR results showed that the polymer was successfully introduced to the nanocomposite. The synthesized intercalated polyacrylamide/clay nanocomposite exhibited a better thickening effect, good viscoelasticity, and better salt resistance and thermal stability than polyacrylamide. In addition, the thickening capacity and thermal stability were superior to the salt-resistant polymer, with a 16.0% higher thickening viscosity and a 15.1% higher viscosity retention rate at 85 °C for 60 d. The intercalated polyacrylamide/clay nanocomposite further expanded the application of polyacrylamide in petroleum exploitation.

12.
iScience ; 26(7): 107132, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37456858

RESUMEN

To address the electromagnetic wave (EMW) pollution issues caused by the development of electronics and wireless communication technology, it is urgent to develop efficient EMW-absorbing materials. With controllable composition, diverse structure, high porosity, and large specific surface area, metal-organic framework (MOF) derivatives have sparked the infinite passion and creativity of researchers in the electromagnetic field. Against the challenges of poor inherent impedance matching and insufficient attenuation capability of pure MOF derivative, designing and developing MOF derivative-based composites by compounding MOF with other materials, such as graphene, CNTs, MXene, and so on, has been an effective strategy for constructing high-efficiency EMW absorbing materials. This review systematically expounds the research progress of MOF derivative-based composite strategies, and discusses the challenges and opportunities faced by MOF derivatives in the field of EMW absorption. This work can provide some good ideas for researchers to design and prepare high-efficiency MOF-based EMW absorbing materials in applications of next-generation electronics and aerospace.

13.
Adv Mater ; 35(1): e2207969, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36281792

RESUMEN

Ambient-pressure-dried (APD) preparation of transition metal carbide/nitrides (MXene) aerogels is highly desirable yet remains highly challenging. Here, ultrathin, high-strength-to-weight-ratio, renewable cellulose nanofibers (CNFs) are efficiently utilized to assist in the APD preparation of ultralight yet robust, highly conductive, large-area MXene-based aerogels via a facile, energy-efficient, eco-friendly, and scalable freezing-exchanging-drying approach. The strong interactions of large-aspect-ratio CNF and MXene as well as the biomimetic nacre-like microstructure induce high mechanical strength and stability to avoid the structure collapse of aerogels in the APD process. Abundant functional groups of CNFs facilitate the chemical crosslinking of MXene-based aerogels, significantly improving the hydrophobicity, water resistance, and even oxidation stability. The ultrathin, 1D nature of the CNF renders the minimal MXenes' interlayered gaps and numerous heterogeneous interfaces, yielding the excellent conductivity and electromagnetic interference (EMI) shielding performance of aerogels. The synergies of the MXene, CNF, and abundant pores efficiently improve the EMI shielding performance, photothermal conversion, and absorption of viscous crude oil. This work shows great promises of the APD, multifunctional MXene-based aerogels in electromagnetic protection or compatibility, thermal therapy, and oil-water separation applications.

14.
Nanomicro Lett ; 15(1): 240, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37917275

RESUMEN

There is an urgent demand for flexible, lightweight, mechanically robust, excellent electromagnetic interference (EMI) shielding materials. Two-dimensional (2D) transition metal carbides/nitrides (MXenes) have been potential candidates for the construction of excellent EMI shielding materials due to their great electrical electroconductibility, favorable mechanical nature such as flexibility, large aspect ratios, and simple processability in aqueous media. The applicability of MXenes for EMI shielding has been intensively explored; thus, reviewing the relevant research is beneficial for advancing the design of high-performance MXene-based EMI shields. Herein, recent progress in MXene-based macrostructure development is reviewed, including the associated EMI shielding mechanisms. In particular, various structural design strategies for MXene-based EMI shielding materials are highlighted and explored. In the end, the difficulties and views for the future growth of MXene-based EMI shields are proposed. This review aims to drive the growth of high-performance MXene-based EMI shielding macrostructures on basis of rational structural design and the future high-efficiency utilization of MXene.

15.
ACS Nano ; 17(13): 12510-12518, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37350557

RESUMEN

Metal-organic frameworks (MOFs) manifest enormous potential in promoting electromagnetic wave (EMW) absorption thanks to the tailored components, topological structure, and high porosity. Herein, rodlike conductive MOFs (cMOFs) composed of adjustable metal ions of Zn, Cu, Co, or Ni and ligands of hexahydroxytriphenylene (HHTP) are prepared to attain tunable dielectric properties for a tailored EMW absorption. Specifically, the influences of the cMOFs' composition, charge transport characteristic, topological crystalline structure, and anisotropy microstructure on dielectric and EMW absorption performance are ascertained, advancing the understanding of EMW attenuation mechanisms of MOFs. The boosted conductive and polarization losses derived from the conjugation effects and terminal groups, as well as shape anisotropy, lead to a prominent EMW absorption of the cMOFs. The Cu-HHTP confers a minimum reflection loss (RLmin) of -63.55 dB at the thickness of 2.9 mm and a maximum effective absorption bandwidth of 5.2 GHz. Moreover, Zn-HHTP showcases the absorption superiority in the S-band (2-4 GHz) with an RLmin of -62.8 dB at a thickness of 1.9 mm. This work not only hoists the mechanistic understanding of the structure-function relationships for the cMOFs but also offers guidelines for preparing functional MOF materials.

16.
Medicine (Baltimore) ; 101(39): e30621, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36181033

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is the most common kind of kidney cancer with poor prognosis. Necroptosis is a newly observed type of programmed cell death in recent years. However, the effects of necroptosis-related lncRNAs (NRlncRNAs) on ccRCC have not been widely explored. The transcription profile and clinical information were obtained from The Cancer Genome Atlas. Necroptosis-related lncRNAs were identified by utilizing a co-expression network of necroptosis-related genes and lncRNAs. Univariate Cox regression, least absolute shrinkage, and selection operator regression and multivariate Cox regression were performed to screen out ideal prognostic necroptosis-related lncRNAss and develop a multi-lncRNA signature. Finally, 6 necroptosis-related lncRNA markers were established. Patients were separated into high- and low-risk groups based on the performance value of the median risk score. Kaplan-Meier analysis identified that high-risk patients had poorer prognosis than low-risk patients. Furthermore, the area under time-dependent receiver operating characteristic curve reached 0.743 at 1 year, 0.719 at 3 years, and 0.742 at 5 years, which indicating that they can be used to predict ccRCC prognosis. In addition, the proposed signature was related to immunocyte infiltration. A nomogram model was also established to provide a more beneficial prognostic indicator for the clinic. Altogether, in the present study, the 6-lncRNA prognostic risk signature are trustworthy and effective indicators for predicting the prognosis of ccRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , ARN Largo no Codificante , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología , Necroptosis/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
17.
ACS Nano ; 16(9): 15042-15052, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-35984219

RESUMEN

Developing high-performance and functional hydrogels that mimic biological materials in nature is promising yet remains highly challenging. Through a facile, scalable unidirectional freezing followed by a salting-out approach, a type of hydrogels composed of "trashed" MXene sediment (MS) and biomimetic pores is manufactured. By integrating the honeycomb-like ordered porous structure, highly conductive MS, and water, the electromagnetic interference (EMI) shielding effectiveness is up to 90 dB in the X band and can reach more than 40 dB in the ultrabroadband gigahertz band (8.2-40 GHz) for the highly flexible hydrogel, outperforming previously reported porous EMI shields. Moreover, thanks to the stable framework of the MS-based hydrogel, the influences of water on shielding performance are quantitatively identified. Furthermore, the extremely low content of silver nanowire is embedded into the biomimetic hydrogels, leading to the significantly improved multiple reflection-induced microwave loss and thus EMI shielding performance. Last, the MS-based hydrogels allow sensitive and reliable detection of human motions and smart coding. This work thus not only achieves the control of EMI shielding performance via the interior porous structure of hydrogels, but also demonstrates a waste-free, low-cost, and scalable strategy to prepare multifunctional, high-performance MS-based biomimetic hydrogels.


Asunto(s)
Biomimética , Nanocables , Humanos , Hidrogeles , Microondas , Porosidad , Plata , Agua
18.
Artículo en Inglés | MEDLINE | ID: mdl-36300842

RESUMEN

The development of flexible composites based on the transition metal carbides/nitrides (MXenes) is gaining popularity because of MXenes' high application potentials for electromagnetic interference (EMI) shields. Here, we prepare a new type of ultraflexible composite films composed of "trashed" MXene sediment (MS) and waterborne polyurethane using a simple, facile solution casting approach. In addition to the outstanding mechanical strength and electrical conductivity, an extremely wide-range of MS contents can be achieved for the composites, resulting in EMI shielding effectiveness (SE) that may be controlled over a wide range. The X-band EMI SE of the flexible, low-density composites containing 70 wt % MS reaches 45.3 dB at a thickness of merely 0.51 mm. Moreover, the SE values of more than 34.5 dB in the ultrabroadband gigahertz frequency range including X-band, P-band, K-band, and R-band, are accomplished for the thin composites. Furthermore, the MS/WPU composite films show excellent electrothermal and photothermal performance, demonstrating the multifunctionalities of the MS-based EMI shields. Combined with the cost-efficient, sustainable, and scalable preparation approach, the ultraflexible, multifunctional composites from "trashed MXene" show great potentials for next-generation electronics. This work also opens a new avenue for the creation of innovative, high-performance, multifunctional flexible composites.

19.
ACS Nano ; 16(11): 19293-19304, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36260760

RESUMEN

Lightweight, thin, large-area, and ultraflexible chemical-cross-linked MXene/superaligned carbon nanotube composite films with a bicontinuous structure are manufactured. The films exhibit high mechanical strength, good electrical conductivity, hydrophobicity, and oxidation stability, as well as wearable multifunctionalities involving electromagnetic interference (EMI) shielding, electrothermal conversion, and photothermal antibacterial performance. An X-band EMI shielding effectiveness (SE) of 24 to 70 dB at the thickness of 8 to 28 µm and an SE of more than 60 dB in ultrabroadband frequency range of 8.2-40 GHz are accomplished. A surface specific SE of 122 368 dB·cm2·g-1 is achieved, significantly outperforming other typical shields reported. The good electro-/photothermal performance of the films leads to high-efficiency deicing and antibacterial performance. Combined with the efficient and scalable manufacturing approach, the multifunctional wearable bicontinuous films show great potential for applications in wearable devices, defense, antibacterials, and the Internet of Things.


Asunto(s)
Nanotubos de Carbono , Nanotubos de Carbono/química , Antibacterianos/farmacología
20.
Nanomicro Lett ; 14(1): 59, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35138506

RESUMEN

Lightweight, ultra-flexible, and robust crosslinked transition metal carbide (Ti3C2 MXene) coated polyimide (PI) (C-MXene@PI) porous composites are manufactured via a scalable dip-coating followed by chemical crosslinking approach. In addition to the hydrophobicity, anti-oxidation and extreme-temperature stability, efficient utilization of the intrinsic conductivity of MXene, the interfacial polarization between MXene and PI, and the micrometer-sized pores of the composite foams are achieved. Consequently, the composites show a satisfactory X-band electromagnetic interference (EMI) shielding effectiveness of 22.5 to 62.5 dB at a density of 28.7 to 48.7 mg cm-3, leading to an excellent surface-specific SE of 21,317 dB cm2 g-1. Moreover, the composite foams exhibit excellent electrothermal performance as flexible heaters in terms of a prominent, rapid reproducible, and stable electrothermal effect at low voltages and superior heat performance and more uniform heat distribution compared with the commercial heaters composed of alloy plates. Furthermore, the composite foams are well attached on a human body to check their electromechanical sensing performance, demonstrating the sensitive and reliable detection of human motions as wearable sensors. The excellent EMI shielding performance and multifunctionalities, along with the facile and easy-to-scalable manufacturing techniques, imply promising perspectives of the porous C-MXene@PI composites in next-generation flexible electronics, aerospace, and smart devices.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA