Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842082

RESUMO

Biological ion channels exhibit switchable cation transport with ultrahigh selectivity for efficient energy conversion, such as Ca2+-activated TRPM4 channels tuned by cation-π interactions, but achieving an analogous highly selective function is challenging in artificial nanochannels. Here, we design a TRPM4-inspired cation-selective nanochannel (CN) assembled by two poly(ether sulfone)s, respectively, with sulfonate acid and indole moieties, which act as cation-selective activators to manage Na+/Cl- selectivity via ionic and cation-π interactions. The cation selectivity of CNs can be activated by Na+, and thereby the Na+ transference number significantly improves from 0.720 to 0.982 (Na+/Cl- selectivity ratio from 2.6 to 54.6) under a 50-fold salinity gradient, surpassing the K+ transference number (0.886) and Li+ transference number (0.900). The TRPM4-inspired nanochannel membrane enabled a maximum output power density of 5.7 W m-2 for salinity-gradient power harvesting. Moreover, a record energy conversion efficiency of up to 46.5% is provided, superior to most nanochannel membranes (below 30%). This work proposes a novel strategy to biomimetic nanochannels for highly selective cation transport and high-efficiency salinity-gradient energy conversion.

2.
Small ; 20(4): e2305613, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37712119

RESUMO

Covalent organic frameworks (COFs) are a family of engaging membrane materials for molecular separation, which remain challenging to fabricate in the form of thin-film composite membranes due to slow crystal growth and insoluble powder. Here, an additive approach is presented to construct COF-based thin-film composite membranes in 10 min via COF oligomer coating onto poly(ether ether ketone) (PEEK)ultrafiltration membranes. By the virtue of ultra-thin liquid phase and liquid-solid interface-confined assembly, the COF oligomers are fast stacked up and grow along the interface with the solvent evaporation. Benefiting from the low out-plane resistance of COFs, COF@PEEK composite membranes exhibit high solvent permeances in a negative correlation with solvent viscosity. The well-defined pore structures enable high molecular sieving ability (Mw = 300 g mol-1 ). Besides, the COF@PEEK composite membranes possess excellent mechanical integrities and steadily operate for over 150 h in the condition of high-pressure cross flow. This work not only exemplifies the high-efficiency and scale-up preparation of COF-based thin-film composite membranes but also provides a new strategy for COF membrane processing.

3.
Small ; : e2402842, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38923165

RESUMO

The nacre-inspired multi-nanolayer structure offers a unique combination of advanced mechanical properties, such as strength and crack tolerance, making them highly versatile for various applications. Nevertheless, a significant challenge lies in the current fabrication methods, which is difficult to create a scalable manufacturing process with precise control of hierarchical structure. In this work, a novel strategy is presented to regulate nacre-like multi-nanolayer films with the balance mechanical properties of stiffness and toughness. By utilizing a co-continuous phase structure and an extensional stress field, the hierarchical nanolayers is successfully constructed with tunable sizes using a scalable processing technique. This strategic modification allows the robust phase to function as nacre-like platelets, while the soft phase acts as a ductile connection layer, resulting in exceptional comprehensive properties. The nanolayer-structured films demonstrate excellent isotropic properties, including a tensile strength of 113.5 MPa in the machine direction and 106.3 MPa in a transverse direction. More interestingly, these films unprecedentedly exhibit a remarkable puncture resistance at the same time, up to 324.8 N mm-1, surpassing the performance of other biodegradable films. The scalable fabrication strategy holds significant promise in designing advanced bioinspired materials for diverse applications.

4.
Food Microbiol ; 121: 104510, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637074

RESUMO

Mycotoxins, as secondary metabolites produced by fungi, have been the focus of researchers in various countries and are considered to be one of the major risk factors in agricultural products. There is an urgent need for a rapid, simple and high-performance method to detect residues of harmful mycotoxins in agricultural foods. We have developed a gold nanoparticle-based multiplexed immunochromatographic strip biosensor that can simultaneously detect fifteen mycotoxins in cereal samples. With this optimized procedure, five representative mycotoxins, deoxynivalenol (DON), zearalenone (ZEN), T-2 toxin (T-2), tenuazonic acid (TEA) and alternariol (AOH) were detected in the range of 0.91-4.77, 0.04-0.56, 0.11-0.68, 0.12-1.02 and 0.09-0.75 ng/mL, respectively. The accuracy and stability of these measurements were demonstrated by analysis of spiked samples with recoveries of 91.8%-115.3% and coefficients of variation <8.7%. In addition, commercially available samples of real cereals were tested using the strips and showed good agreement with the results verified by LC-MS/MS. Therefore, Our assembled ICA strips can be used for the simultaneous detection of 5 mycotoxins and their analogs (15 mycotoxins in total) in grain samples, and the results were consistent between different types of cereal foods, this multiplexed immunochromatographic strip biosensor can be used as an effective tool for the primary screening of mycotoxin residues in agricultural products.


Assuntos
Nanopartículas Metálicas , Micotoxinas , Micotoxinas/análise , Ouro/análise , Ouro/química , Cromatografia Líquida , Contaminação de Alimentos/análise , Nanopartículas Metálicas/análise , Nanopartículas Metálicas/química , Espectrometria de Massas em Tandem , Grão Comestível/microbiologia
5.
Plant Dis ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268177

RESUMO

Elaeocarpus decipiens is widely cultivated as an ornamental tree of commercial importance in southern China. During March 2018 to March 2021, leaf spot disease was observed in about 40% of E. decipiens on the campus of Jiangnan University in Wuxi, Jiangsu, China (31.48°N, 120.46°E). Leaf symptoms began as small, light brown lesions that enlarged, turned olive brown in color and then became necrotic. Ten symptomatic leaves were collected from five different trees on the Jiangnan University campus and surface sterilized with 75% ethanol for 30 seconds, followed by 1% sodium hypochlorite for 1 minute, and rinsed three times with sterile distilled water before being cultured onto potato dextrose agar and incubated in the dark at 25°C for 5 days. Five purified fungal isolates were obtained by the single spore isolation method. Emergent fungal colonies were olive-green in color with 1 to 3 mm white margins and abundant aerial hyphae. Conidia were borne in chains or singly and were obclavate or obpyriform and measured 6.5 to 17.4 × 21.3 to 32.8 µm (n=50) with one to seven transverse septa and zero to three longitudinal septa. Based on morphological characteristics, the pathogen was identified as Alternaria spp.(Simmons 2007). Three representative isolates, At1, At2 and At3, were selected for molecular identification, total genomic DNA of the fungus isolates were extracted with Plant/Fungi DNA Isolation Kit (Sigma-Aldrich, Ontario, Canada). Plasma membrane ATPase (ATP) gene, chitin synthase (CHS) gene and translation elongation factor 1-alpha (EF1) gene were amplified with primers ATPDF1/ATPDR1, CHS-79F/CHS-345R (Lawrence et al. 2013) and EF1-728F/EF1-986R (Carbone and Kohn 1999). The amplification results of the three isolate genes were consistent, and we deposited the results of the ATP (MN046377), CHS (MN046378) and EF1 (MN046379) sequences of At1 in the NCBI GeneBank. The ATPase gene from the representative isolate At1 shared 99.83% similarity to A. alternata causing leaf Spot of Codonopsis pilosula in China (OM362504, Shi et al. 2022), the CHS gene shared 100% similarity to A. alternata causing brown leaf spot on Paris polyphylla var. chinensis in China (MK391053, Fu et al. 2019), and the EF1 gene shared 100% similarity to A. alternata CBS 916.96 ex-type on Arachis hypogaea in India (KC584634). A phylogenetic tree constructed with the EF1 gene using the neighbor-joining algorithm in MEGA 11 software with 1,000 bootstrap replicates revealed that the examined isolate, At1, belongs to the fungus A. alternata. For pathogenicity tests, 10 leaves of five healthy plants were sprayed with spore suspensions (1 × 107 conidia/ml) of the 10-day-old isolates (At1, At2 and At3, respectively). As a control, five plants were sprayed with sterile distilled water. After inoculation, use the bags to moisturize for 48 hours. Pathogenicity tests were conducted three times. Fourteen days after inoculation, olive brown necrotic lesions developed on inoculated leaves while control leaves remained symptomless. The pathogen was reisolated from infected leaves and confirmed as A. alternata based on morphological characteristics and molecular markers. To date, A. alternata has been reported to cause leaf spot disease on many plants inculuding Ficus religiosa (Du et al. 2022), Tilia miqueliana (Yue et al. 2023), Ligustrum japonicum (Fang et al. 2023) and so on. To our knowledge, this is the first report of the occurrence of A. alternata causing leaf spot on E. decipiens in China. The increasing area of E. decipiens cultivation and global climate change have led to an increase in the incidence of E. decipiens diseases, which should be taken into account by forest conservationists.

6.
Angew Chem Int Ed Engl ; 63(14): e202318387, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38349735

RESUMO

In this study, we introduce an electrochemical doping strategy aimed at manipulating the structure and composition of electrically conductive metal-organic frameworks (c-MOFs). Our methodology is exemplified through a representative c-MOF, Ni3(HITP)2 (HITP=2, 3, 6, 7, 10, 11-hexaiminotriphenylene), synthesized into porous thin films supported by nanocellulose. While the c-MOF exhibits characteristic capacitive behavior in neutral electrolyte; it manifests redox behaviors in both acidic and alkaline electrolytes. Evidence indicates that the organic ligands within c-MOF undergo oxidation (p-doping) and reduction (n-doping) when exposed to specific electrochemical potentials in acidic and alkaline electrolyte, respectively. Interestingly, the p-doping process proves reversible, with the c-MOF structure remaining stable across cyclic p-doping/de-doping. In contrast, the n-doping is irreversible, leading to the gradual decomposition of the framework into inorganic species over a few cycles. Drawing on these findings, we showcase the versatile electrochemical applications of c-MOFs and their derived composites, encompassing electrochemical energy storage, electrocatalysis, and ultrafast actuation. This study provides profound insights into the doping of c-MOFs, offering a new avenue for modulating their chemical and electronic structure, thereby broadening their potential for diverse electrochemical applications.

7.
BMC Genomics ; 24(1): 507, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648967

RESUMO

BACKGROUND: The Mongolian gazelle (Procapra gutturosa) population has shown a considerable range of contractions and local extinctions over the last century, owing to habitat fragmentation and poaching. A thorough understanding of the genetic diversity and structure of Mongolian gazelle populations in fragmented habitats is critical for planning effective conservation strategies. RESULT: In this study, we used eight microsatellite loci and mitochondrial cytochrome b (Cytb) to compare the levels of genetic diversity and genetic structure of Mongolian gazelle populations in the Hulun Lake National Nature Reserve (HLH) with those in the China-Mongolia border area (BJ). The results showed that the nucleotide diversity and observed heterozygosity of the HLH population were lower than those of the BJ population. Moreover, the HLH and BJ populations showed genetic differentiation. We concluded that the HLH population had lower genetic diversity and a distinct genetic structure compared with the BJ population. CONCLUSION: The genetic diversity of fragmented Mongolian gazelle populations, can be improved by protecting these populations while reinforcing their gene exchange with other populations. For example, attempts can be made to introduce new individuals with higher genetic diversity from other populations to reduce inbreeding.


Assuntos
Antílopes , Humanos , Animais , Antílopes/genética , China , Citocromos b/genética , Deriva Genética , Variação Genética
8.
Int J Mol Sci ; 24(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37298549

RESUMO

The Corsac fox (Vulpes corsac) is a species of fox distributed in the arid prairie regions of Central and Northern Asia, with distinct adaptations to dry environments. Here, we applied Oxford-Nanopore sequencing and a chromosome structure capture technique to assemble the first Corsac fox genome, which was then assembled into chromosome fragments. The genome assembly has a total length of 2.2 Gb with a contig N50 of 41.62 Mb and a scaffold N50 of 132.2 Mb over 18 pseudo-chromosomal scaffolds. The genome contained approximately 32.67% of repeat sequences. A total of 20,511 protein-coding genes were predicted, of which 88.9% were functionally annotated. Phylogenetic analyses indicated a close relation to the Red fox (Vulpes vulpes) with an estimated divergence time of ~3.7 million years ago (MYA). We performed separate enrichment analyses of species-unique genes, the expanded and contracted gene families, and positively selected genes. The results suggest an enrichment of pathways related to protein synthesis and response and an evolutionary mechanism by which cells respond to protein denaturation in response to heat stress. The enrichment of pathways related to lipid and glucose metabolism, potentially preventing stress from dehydration, and positive selection of genes related to vision, as well as stress responses in harsh environments, may reveal adaptive evolutionary mechanisms in the Corsac fox under harsh drought conditions. Additional detection of positive selection for genes associated with gustatory receptors may reveal a unique desert diet strategy for the species. This high-quality genome provides a valuable resource for studying mammalian drought adaptation and evolution in the genus Vulpes.


Assuntos
Cromossomos , Raposas , Animais , Raposas/genética , Filogenia , Cromossomos/genética , Genoma/genética , Sequências Repetitivas de Ácido Nucleico
9.
Chemistry ; 28(24): e202104562, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35289447

RESUMO

The outer coordination sphere of metalloenzyme often plays an important role in its high catalytic activity, however, this principle is rarely considered in the design of man-made molecular catalysts. Herein, four Ru-bda (bda=2,2'-bipyridine-6,6'-dicarboxylate) based molecular water oxidation catalysts with well-defined outer spheres are designed and synthesized. Experimental and theoretical studies showed that the hydrophobic environment around the Ru center could lead to thermodynamic stabilization of the high-valent intermediates and kinetic acceleration of the proton transfer process during catalytic water oxidation. By this outer sphere stabilization, a 6-fold rate increase for water oxidation catalysis has been achieved.


Assuntos
Prótons , Água , Catálise , Humanos , Cinética , Oxirredução , Água/química
10.
Microb Ecol ; 83(3): 753-765, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34189610

RESUMO

The gut microbiome is integral for the host's living and environmental adaptation and crucially important for understanding host adaptive mechanisms. The red fox (Vulpes vulpes) dominates a wider ecological niche and more complicated habitat than that of the corsac fox (V. corsac). However, the adaptive mechanisms (in particular, the gut microbiome responsible for this kind of difference) are still unclear. Therefore, we investigated the gut microbiome of these two species in the Hulunbuir grassland, China, and evaluated their microbiome composition, function, and adaptive mechanisms. We profiled the gut microbiome and metabolism function of red and corsac foxes via 16S rRNA gene and metagenome sequencing. The foxes harbored species-specific microbiomes and functions that were related to ecological niche and habitat. The red fox had abundant Bacteroides, which leads to significant enrichment of metabolic pathways (K12373 and K21572) and enzymes related to chitin and carbohydrate degradation that may help the red fox adapt to a wider niche. The corsac fox harbored large proportions of Blautia, Terrisporobacter, and ATP-binding cassette (ABC) transporters (K01990, K02003, and K06147) that can help maintain corsac fox health, allowing it to live in harsh habitats. These results indicate that the gut microbiome of the red and corsac foxes may have different abilities which may provide these species with differing capabilities to adapt to different ecological niches and habitats, thus providing important microbiome data for understanding the mechanisms of host adaptation to different niches and habitats.


Assuntos
Raposas , Microbioma Gastrointestinal , Animais , Ecossistema , RNA Ribossômico 16S/genética , Especificidade da Espécie
11.
Analyst ; 146(11): 3589-3598, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33928961

RESUMO

Chlorpheniramine (CPM) is an illegal additive found in herbal teas and health foods, and its excessive intake can cause health problems. In this study, a CPM monoclonal antibody (mAb) was developed based on a new type of hapten. The mAb was found to belong to the IgG2b subclass and showed high sensitivity and specificity when used in ELISA, with a half-maximal inhibitory concentration (IC50) of 0.98 ng mL-1 and cross-reactivity (CR) values below 1.8% when compared to antiallergic drugs. Based on the mAb produced, a fluorescent microsphere-based immunochromatographic strip assay (FM-ICS) and a gold nanoparticle-based immunochromatographic strip assay (GNP-ICS) were developed for the rapid and sensitive detection of CPM in herbal tea samples. Under optimal conditions, the cut-off values for the FM-ICS and GNP-ICS were 10 ng mL-1 and 100 ng mL-1, respectively, in herbal tea samples. The FM-ICS exhibited a higher sensitivity than GNP-ICS, but both could produce results within 15 min. In addition, a variety of high-throughput rapid immunoassay formats could be implemented based on this mAb for use as a convenient and reliable tool for the determination of CPM exposure in foods and the environment.


Assuntos
Ouro , Nanopartículas Metálicas , Clorfeniramina , Cromatografia de Afinidade , Coloide de Ouro , Limite de Detecção
12.
Acc Chem Res ; 52(8): 2232-2243, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31290643

RESUMO

Because of its natural abundance, hierarchical fibrous structure, mechanical flexibility, potential for chemical modification, biocompatibility, renewability, and abundance, cellulose is one of the most promising green materials for a bio-based future and sustainable economy. Cellulose derived from wood or bacteria has dominated the industrial cellulose market and has been developed to produce a number of advanced materials for applications in energy storage, environmental, and biotechnology areas. However, Cladophora cellulose (CC) extracted from green algae has unprecedented advantages over those celluloses because of its high crystallinity (>95%), low moisture adsorption capacity, excellent solution processability, high porosity in the mesoporous range, and associated high specific surface area. The unique physical and chemical properties of CC can add new features to and enhance the performance of nanocellulose-based materials, and these attributes have attracted a great deal of research interest over the past decade. This Account summarizes our recent research on the preparation, characterization, functionalization, and versatile applications of CC. Our aim is to provide a comprehensive overview of the uniqueness of CC with respect to material structure, properties, and emerging applications. We discuss the potential of CC in energy storage, environmental science, and life science, with emphasis on applications in which its properties are superior to those of other nanocellulose forms. Specifically, we discuss the production of the first-ever paper battery based on CC. This battery has initiated a rising interest in the development of sustainable paper-based energy storage devices, where cellulose is used as a combined building block and binder for paper electrodes of various types in combination with carbon, conducting polymers, and other electroactive materials. High-active-mass and high-mass-loading paper electrodes can be made in which the CC acts as a high-surface-area and porous substrate while a thin layer of electroactive material is coated on individual nanofibrils. We have shown that CC membranes can be used directly as battery separators because of their low moisture content, high mesoporosity, high thermal stability, and good electrolyte wettability. The safety, stability, and capacity of lithium-ion batteries can be enhanced simply by using CC-based separators. Moreover, the high chemical modifiability and adjustable porosity of dried CC papers allow them to be used as advanced membranes for environmental science (water and air purification, pollutant adsorption) and life science (virus isolation, protein recovery, hemodialysis, DNA extraction, bioactive substrates). Finally, we outline some concluding perspectives on the challenges and future directions of CC research with the aim to open up yet unexplored fields of use for this interesting material.


Assuntos
Celulose/química , Clorófitas/química , Nanofibras/química , Filtros de Ar , Linhagem Celular , Celulose/ultraestrutura , Fontes de Energia Elétrica , Eletrodos , Filtração/instrumentação , Filtração/métodos , Humanos , Nanofibras/ultraestrutura , Porosidade , Purificação da Água/instrumentação , Purificação da Água/métodos
13.
Analyst ; 145(22): 7088-7102, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-32990695

RESUMO

The widespread presence of mycotoxins in nature not only poses a huge health risk to people in terms of food but also causes incalculable losses to the agricultural economy. As a rapidly developing technology in recent years, the mycotoxin immunoassay technology has approached or even surpassed the traditional chromatography technology in some aspects. Using this approach, the lateral flow immunoassay (LFIA) has attracted the interest of researchers due to its user-friendly operation, short time consumption, little interference, low cost, and ability to process a large number of samples at the same time. This paper provides an overview of the immunogens commonly used for mycotoxins, the development of antibodies, and the use of gold nanoparticles, quantum dots, carbon nanoparticles, enzymes, and fluorescent microsphere labeling materials for the construction of LFIAs to improve detection sensitivity. The analytical performance, detection substrates, detection limits or detection ranges of LFIA for mycotoxins have been listed in recent years. Finally, we describe the future outlook for the field, predicting that portable mobile detection devices and simultaneous quantitative detection of multiple mycotoxins is one of the important directions for future development.


Assuntos
Nanopartículas Metálicas , Micotoxinas , Pontos Quânticos , Ouro , Humanos , Imunoensaio , Limite de Detecção , Micotoxinas/análise
14.
Opt Express ; 27(11): 15968-15981, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31163785

RESUMO

Calibration is required to maximize the sensitivity and measurement accuracy of vibration sensors. In this study, a low-frequency vibration calibration method is proposed that is based on the concept of monocular vision. In this method, we employ a high-accuracy edge extraction method to extract the edges of sequential images so as to obtain the high calibration accuracy. However, the proposed method must rely on a long-stroke shaker to provide vibration excitation to the sensor, and the bending in the guideway caused by the mechanical processing reduces the calibration accuracy, especially at very low frequencies. The proposed setting compensates for the bending using an additional monocular vision technique to significantly improve the calibration accuracy. To validate the calibration accuracy of the proposed method, a comparison was conducted between results obtained via the laser interferometry, the Earth's gravitation method, and the proposed method when applied to calibrate the sensitivity of a tri-axial acceleration sensor at frequencies between 0.04 and 8 Hz. The results of the comparison showed the proposed method calibrated the sensor sensitivity with high accuracy and was able to accurately account for the bending when the frequency was lower than 0.3 Hz. In contrast, the calibration accuracy of the laser interferometry decreased because of the bending.

15.
Chemistry ; 25(14): 3515-3520, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30688380

RESUMO

Freestanding nanopapers were fabricated by the assembly of metal-organic frameworks (MOFs) onto cellulose nanofibers (CNFs). The CNFs are wrapped by continuously nucleated MOF layers (CNF@MOF) by interfacial synthesis, with the charge density on the surface of the CNFs and the dosage of the surfactant polyvinylpyrrolidone (PVP) being carefully adjusted. The obtained CNF@MOF nanofibers with long-range, continuous, hybrid nanostructures were very different to the composites formed by aggregation of MOF nanoparticles on the substrates. Four typical MOFs (HKUST-1, Al-MIL-53, Zn-MOF-74, ZIF-CO3 -1) were successfully grown onto CNFs in aqueous solutions and further fabricated into freestanding nanopapers. Because of their unique nanostructures and morphologies, the corresponding flexible nanopapers exhibit hierarchical meso-micropores, high optical transparency, high thermal stability, and high mechanical strength. A proof-of-concept study shows that the CNF@MOF nanopapers can be used as efficient filters to separate volatile organic compounds (VOCs) from the air. This work provides a new path for structuring MOF materials that may boost their practical application.

16.
Polymers (Basel) ; 16(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38543349

RESUMO

With the advent of the Internet of Things, self-powered wearable sensors have become increasingly prevalent in our daily lives. The utilization of piezoelectric composites to harness and sense surrounding mechanical vibrations has been extensively investigated during the last decades. However, the poor interface compatibility between ceramics nanofillers and polymers matrix, as well as low piezoelectric performance, still serves as a critical challenge. In this work, we employed Di(dioctylpyrophosphato) ethylene titanate (DET) as the coupling agent for modifying barium titanate (BTO) nanofillers. Compared to the BTO/PVDF counterpart, the DET-BTO/PVDF nanofibers exhibit an augmented content of piezoelectric ß phase (~85.7%) and significantly enhanced stress transfer capability. The piezoelectric coefficient (d33) is up to ~40 pC/N, which is the highest value among reported BTO/PVDF composites. The piezoelectric energy harvesters (PEHs) present benign durability and attain a high instantaneous power density of 276.7 nW/cm2 at a matched load of 120 MΩ. Furthermore, the PEHs could sense various human activities, with the sensitivity as high as 0.817 V/N ranging from 0.05-0.1 N. This work proposes a new strategy to boosting the piezoelectric performance of PVDF-based composites via DET-doping ceramics nanoparticles, and in turn show significantly improved energy harvesting and sensing capability.

17.
ACS Appl Mater Interfaces ; 16(10): 12996-13005, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422506

RESUMO

Flexible pressure sensors are intensively demanded in various fields such as electronic skin, medical and health detection, wearable electronics, etc. MXene is considered an excellent sensing material due to its benign metal conductivity and adjustable interlayer distance. Exhibiting both high sensitivity and long-term stability is currently an urgent pursuit in MXene-based flexible pressure sensors. In this work, high-strength methylcellulose was introduced into the MXene film to increase the interlayer distance of 2D nanosheets and fundamentally overcome the self-stacking problem. Thus, concurrent improvement of the sensing capability and mechanical strength was obtained. By appropriately modulating the ratio of methylcellulose and MXene, the obtained pressure sensor presents a high sensitivity of 19.41 kPa-1 (0.88-24.09 kPa), good stability (10000 cycles), and complete biodegradation in H2O2 solution within 2 days. Besides, the sensor is capable of detecting a wide range of human activities (pulse, gesture, joint movement, etc.) and can precisely recognize spatial pressure distribution, which serves as a good candidate for next-generation wearable electronic devices.


Assuntos
Peróxido de Hidrogênio , Metilcelulose , Nitritos , Elementos de Transição , Humanos , Movimento (Física) , Biodegradação Ambiental
18.
Mater Horiz ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764435

RESUMO

Wearable electronics are some of the most promising technologies with the potential to transform many aspects of human life such as smart healthcare and intelligent communication. The design of self-powered fabrics with the ability to efficiently harvest energy from the ambient environment would not only be beneficial for their integration with textiles, but would also reduce the environmental impact of wearable technologies by eliminating their need for disposable batteries. Herein, inspired by classical Archimedean spirals, we report a metastructured fiber fabricated by scrolling followed by cold drawing of a bilayer thin film of an MXene and a solid polymer electrolyte. The obtained composite fibers with a typical spiral metastructure (SMFs) exhibit high efficiency for dispersing external stress, resulting in simultaneously high specific mechanical strength and toughness. Furthermore, the alternating layers of the MXene and polymer electrolyte form a unique, tandem ionic-electronic coupling device, enabling SMFs to generate electricity from diverse environmental parameters, such as mechanical vibrations, moisture gradients, and temperature differences. This work presents a design rule for assembling planar architectures into robust fibrous metastructures, and introduces the concept of ionic-electronic coupling fibers for efficient multimodal energy harvesting, which have great potential in the field of self-powered wearable electronics.

19.
Chem Sci ; 15(12): 4538-4546, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516083

RESUMO

Oceans and salt lakes contain vast amounts of uranium. Uranium recovery from natural water not only copes with radioactive pollution in water but also can sustain the fuel supply for nuclear power. The adsorption-assisted electrochemical processes offer a promising route for efficient uranium extraction. However, competitive hydrogen evolution greatly reduces the extraction capacity and the stability of electrode materials with electrocatalytic activity. In this study, we got inspiration from the biomineralisation of marine bacteria under high salinity and biomimetically regulated the electrochemical process to avoid the undesired deposition of metal hydroxides. The uranium uptake capacity can be increased by more than 20% without extra energy input. In natural seawater, the designed membrane electrode exhibits an impressive extraction capacity of 48.04 mg-U per g-COF within 21 days (2.29 mg-U per g-COF per day). Furthermore, in salt lake brine with much higher salinity, the membrane can extract as much uranium as 75.72 mg-U per g-COF after 32 days (2.37 mg-U per g-COF per day). This study provides a general basis for the performance optimisation of uranium capture electrodes, which is beneficial for sustainable access to nuclear energy sources from natural water systems.

20.
Sci Rep ; 14(1): 12944, 2024 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839875

RESUMO

Locomotor preferences and habitat types may drive animal evolution. In this study, we speculated that locomotor preference and habitat type may have diverse influences on Bovidae mitochondrial genes. We used selection pressure and statistical analysis to explore the evolution of mitochondrial DNA (mtDNA) protein-coding genes (PCGs) from diverse locomotor preferences and habitat types. Our study demonstrates that locomotor preference (energy demand) drives the evolution of Bovidae in mtDNA PCGs. The habitat types had no significant effect on the rate of evolution in Bovidae mitochondrial genes. Our study provides deep insight into the adaptation of Bovidae.


Assuntos
DNA Mitocondrial , Evolução Molecular , Genes Mitocondriais , Animais , DNA Mitocondrial/genética , Locomoção/genética , Seleção Genética , Ecossistema , Filogenia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA