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1.
PLoS One ; 19(3): e0293120, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38489326

RESUMEN

Marine fishery carbon emissions play a significant role in agricultural carbon emissions, making resource allocation a crucial topic for the overall marine ecological protection. This paper evaluates the dynamic iteration method as a research approach with the factors of resource allocation consisting of value assessment, optimization objective, difference between value assessment and objective, and optimization calculation. The paper selects the shadow price from the Super-SBM model as the judgment function for the goal value, aiming for the fairness criterion. From an equity standpoint, the allocation of carbon resources in marine capture fisheries proves to be unreasonable. The fishery model exhibits an excessive supply of carbon resources, resulting in wastage, while the green fishery model faces a relatively limited supply, with a focus on energy conservation and environmental protection. To address this issue, this paper proposes a new method and discusses the corrective results. This result shows that the stabilization point achieved is a short-term equilibrium rather than a long-term one. By rectifying the social contradiction of profit-oriented approaches, this research provides a fresh perspective for economic studies and applications, particularly in industrial layout and resource utilization optimization.


Asunto(s)
Conservación de los Recursos Naturales , Explotaciones Pesqueras , Conservación de los Recursos Naturales/métodos , Biología Marina , Carbono
2.
Small ; 20(10): e2306522, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37884468

RESUMEN

Mimicking efficient biocatalytic cascades using nanozymes has gained enormous attention in catalytic chemistry, but it remains challenging to develop a nanozyme-based cascade system to sequentially perform the desired reactions. Particularly, the integration of sequential hydrolysis and oxidation reactions into nanozyme-based cascade systems has not yet been achieved, despite their significant roles in various domains. Herein, a self-cascade Ce-MOF-818 nanozyme for sequential hydrolysis and oxidation reactions is developed. Ce-MOF-818 is the first Ce(IV)-based heterometallic metal-organic framework constructed through the coordination of Ce and Cu to distinct groups. It is successfully synthesized using an improved solvothermal method, overcoming the challenge posed by the significant difference in the binding speeds of Ce and Cu to ligands. With excellent organophosphate hydrolase-like (Km = 42.3 µM, Kcat = 0.0208 min-1 ) and catechol oxidase-like (Km = 2589 µM, Kcat = 1.25 s-1 ) activities attributed to its bimetallic active centers, Ce-MOF-818 serves as a promising self-cascade platform for sequential hydrolysis and oxidation. Notably, its catalytic efficiency surpasses that of physically mixed nanozymes by approximately fourfold, owning to the close integration of active sites. The developed hydrolysis-oxidation self-cascade nanozyme has promising potential applications in catalytic chemistry and provides valuable insights into the rational design of nanozyme-based cascade systems.


Asunto(s)
Estructuras Metalorgánicas , Hidrólisis , Oxidación-Reducción , Estructuras Metalorgánicas/química , Catálisis , Biocatálisis
3.
Geroscience ; 46(2): 2641-2651, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38108993

RESUMEN

In the context of a globally aging population, exploring interventions that counteract age-related cognitive decline and cerebral structural alterations is paramount. Among various strategies, physical exercise (PE) emerges as a prevalent activity routinely incorporated in many individuals' lives. This systematic review and meta-analysis aims to elucidate the impact of PE on white matter (WM) integrity and cognitive function in older adults. Data from 581 participants, 312 in the PE intervention group, and 269 in the control group were extracted from nine randomized controlled trials (RCTs) retrieved from databases including PubMed, Embase, Web of Science, and the Cochrane Library. The results indicated a significant improvement in white matter (WM) integrity in individuals engaged in PE, as evidenced by enhanced fractional anisotropy (FA) scores (SMD = 0.4, 95% confidence interval (CI) [0.05, 0.75], P = 0.024). The GRADE assessment revealed a moderate risk. However, no significant associations were found between PE and other metrics such as radial diffusivity (RD), mean diffusivity (MD), white matter volume (WMV), hippocampal volume (HV), and cognitive functions (executive function [EF], memory, processing speed). In conclusion, our study emphasizes the potential neurostructural and cognitive functional benefits of physical exercise for the brain health of older adults.


Asunto(s)
Sustancia Blanca , Humanos , Anciano , Imagen de Difusión Tensora/métodos , Cognición , Encéfalo , Ejercicio Físico
4.
J Med Chem ; 66(13): 8725-8744, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37382379

RESUMEN

Neuropathic pain (NP) is an intolerable pain syndrome that arises from continuous inflammation and excitability after nerve injury. Only a few NP therapeutics are currently available, and all of them do not provide adequate pain relief. Herein, we report the discovery of a selective and potent inhibitor of the bromodomain and extra-terminal (BET) proteins for reducing neuroinflammation and excitability to treat NP. Starting with the screening hit 1 from an in-house compound library, iterative optimization resulted in the potent BET inhibitor DDO-8926 with a unique binding mode and a novel chemical structure. DDO-8926 exhibits excellent BET selectivity and favorable drug-like properties. In mice with spared nerve injury, DDO-8926 significantly alleviated mechanical hypersensitivity by inhibiting pro-inflammatory cytokine expression and reducing excitability. Collectively, these results implicate that DDO-8926 is a promising agent for the treatment of NP.


Asunto(s)
Descubrimiento de Drogas , Neuralgia , Ratones , Animales , Descubrimiento de Drogas/métodos , Dominios Proteicos , Citocinas , Piridinas/farmacología , Piridinas/uso terapéutico , Neuralgia/tratamiento farmacológico
5.
Bioorg Med Chem ; 90: 117373, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37329678

RESUMEN

N6-methyladenosine (m6A) is the most common mRNA modification in mammalians. The function and dynamic regulation of m6A depends on the "writer", "readers" and "erasers". YT521-B homology domain family (YTHDF) is a class of m6A binding proteins, including YTHDF1, YTHDF2 and YTHDF3. In recent years, the modification of m6A and the molecular mechanism of YTHDFs have been further understood. Growing evidence has shown that YTHDFs participate in multifarious bioprocesses, particularly tumorigenesis. In this review, we summarized the structural characteristics of YTHDFs, the regulation of mRNA by YTHDFs, the role of YTHDF proteins in human cancers and inhibition of YTHDFs.


Asunto(s)
Proteínas Portadoras , Neoplasias , Animales , Humanos , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , ARN Mensajero/metabolismo , Factores de Transcripción/metabolismo , Adenosina/química , Mamíferos/metabolismo , Neoplasias/tratamiento farmacológico
6.
3D Print Addit Manuf ; 10(2): 289-297, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37123522

RESUMEN

Three-dimensional printing (3DP) is considered to be one of the important technologies for a new manufacturing mode. When ceramsite sand is used as a 3DP material to produce a mold (core), the printed layer is prone to deviation from the original location. In this study, the continuous stacking of the printed part deviation was termed as pushing dislocation, and a physical model was designed to investigate the pushing dislocation mechanism. When the gravity of the printing layer and the pressure of the sand scraper decreased, or when the supporting force increased, the angle of the sand scraper and the maximum friction of the prelaying layer on the printed part will reduce the pushing dislocation. To optimize the quality of the ceramsite sand mold, experiments on the pushing dislocation were conducted by altering the recoater speed, layer thickness, and bottom support condition (with or without bottom supporting plate). The sample dimensions were obtained by a 3D imaging scanner, and the gas evolution and ignition loss were measured. The results revealed that the dimensional difference of samples continuously decreased and the pushing dislocation was gradually reduced as the recoater speed and layer thickness increased. The pushing dislocation of the X-direction sample was more severe compared with that of the Y-direction sample. Increasing the layer thickness is an effective way of reducing the pushing dislocation. The bottom supporting plate can reduce the pushing dislocation, but the effect was insignificant.

7.
Artículo en Inglés | MEDLINE | ID: mdl-36901405

RESUMEN

Environmental regulation (ER) is essential to preventing agricultural non-point source pollution (ANSP). Prior research has focused on the effect of ER on agricultural pollution (AP), but little is known about the impact of ER following digitization on preventing AP, particularly ANSP. Based on the spatial heterogeneity, the effect of ER was examined using a geographic detector tool with provincial panel data from 2010 to 2020 in rural China. The results show that ER is a driver in preventing ANSP, primarily because of the constraint on farmers' behavior. Digitization positively affects the prevention of ANSP, as the new impetus for the infrastructure, technology, and capital is supported. The interaction between ER and digitalization forms a driving effect on the prevention of ANSP, indicating that digitalization constitutes the path dependence of farmers' rule acquisition and perception and addresses the "free riding" dilemma of farmers' participation, thereby enabling the incentive of ER to make agricultural production green and efficient. These findings indicate that the endogenous factor of digitization allowing ER is essential to preventing ANSP.


Asunto(s)
Contaminación Difusa , Humanos , Contaminación Difusa/prevención & control , Agricultura , Tecnología , Agricultores , China
8.
Artículo en Inglés | MEDLINE | ID: mdl-36011508

RESUMEN

This study performs the spatial Durbin model (SDM) and threshold model to analyze the efficiency of agricultural green production following technological progress from 1998 through 2019. The SDM supports a nonlinear contribution of technological progress spillover to agricultural green total factor productivity (GTFP), exacerbated by upgrading agricultural structure. Moreover, the threshold model confirms that technological progress has a single threshold effect on agricultural GTFP with the rationalization of the agrarian system as a threshold variable; meanwhile, the contribution of technological progress to agricultural GTFP is less than that of agricultural total factor productivity. Out of the expanded application of dissipative structure theory in agricultural GTFP systems innovatively, this study reveals the urgency to strengthen the innovation of independent technology, lower the threshold for introducing technology, and optimize the agrarian structure in the long-term sustainable agriculture for the economies that are undergoing a similar development stage as China.


Asunto(s)
Agricultura , Tecnología , China , Desarrollo Económico , Eficiencia
9.
Eur J Med Chem ; 238: 114423, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35544982

RESUMEN

Sepsis has long been a major health problem worldwide. It threatens the lives of hospitalized patients and has been one of the leading causes of death in hospitalized patients over the past decades. BRD4 has been regarded as a potential target for sepsis therapy, for its critical role in the transcriptional expression of NF-κB pathway-dependent inflammatory factors. In this study, compound 1 was obtained through virtual screening, and candidate compound 27 was obtained through several rounds of iterative SAR analysis. 27 decreased LPS-induced NO production and expression of the pro-inflammatory factors IL-6, IL-1ß and TNF-α. In vivo, 27 effectively protected mice from LPS-induced sepsis, increased survival rate and decreased the level of pro-inflammatory factors in serum. Collectively, we reported here 27, a BRD4 inhibitor with a new scaffold, as a potential candidate for the treatment of sepsis.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas Nucleares , Sepsis , Factores de Transcripción , Animales , Proteínas de Ciclo Celular/antagonistas & inhibidores , Humanos , Lipopolisacáridos , Ratones , FN-kappa B/metabolismo , Sepsis/tratamiento farmacológico , Factores de Transcripción/antagonistas & inhibidores
10.
Interdiscip Sci ; 14(2): 471-484, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35150388

RESUMEN

BACKGROUND: The outbreak of COVID-19 sweeping the globe in 2020 has caused widespread fear and threatened global health security. Compared to SARS and MERS, COVID-19 also causes severe respiratory diseases and even fatal diseases but have many differences, such as the unidentified gene sequence and replication mechanism. From SARS to MERS, and then to COVID-19, coronaviruses have significant variations in host adaptation, virus evolution, infectivity, spread, and pathogenicity due to its unique replication mechanism. METHODS: A field of research for the coronavirus replication in humans was visualized with a database covering 9177 kinds of literature in Web of Science from 2002 through October 2021 to provide cognitive direction for the epidemic situation of virus infection. Knowledge Mapping by CiteSpace and Bibliometrix Package in R Software was drawn to depict the underlying features of viral replication and changing trends of studies, with these analyses including co-citation, density visualization, keyword clustering, and time zone. RESULTS: The keyword frequencies of "replication," ''infection," and ''spike protein" repeatedly appeared in published papers. Coronavirus can promote or inhibit apoptosis, depending on the balance between viral protein and apoptotic factors. When the living environment of cells is irreversibly damaged by the virus, cells have to start the apoptosis mechanism to prevent the replication, transmission, and spread of the virus. The replication, assembly and transmission of coronavirus can inhibit cells from entering the apoptosis prematurely with the fusion of spike protein and cell receptor in human. CONCLUSION: Our results indicated that "viral infection," spike protein," and "mutation" might be future research hotspots on coronavirus replication in humans. The attention should be paid to the mutations of S protein and these mutants carrying mutations.


Asunto(s)
COVID-19 , Coronavirus del Síndrome Respiratorio de Oriente Medio , Humanos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
11.
Sci Total Environ ; 799: 149459, 2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34371402

RESUMEN

Polyhalogenated carbazoles (PHCZs) have been detected in various environments frequently and have attracted increasing attention for their multiple toxicities. However, only a few reports record the occurrence of PHCZs in farmland soils, and the sources of which were not yet been implemented. In this study, 12 PHCZs and carbazole (CZ) were screened in farmland soil samples from the Three Northeast Provinces, and the ∑PHCZs were in the range of 18.16-219.67 ng/g dw. 36-CCZ was the dominant congener (40.67%) in farmland soils, followed by 3-CCZ (14.51%), and average percentages of other congeners were lower than 10%. A concrete analysis of the sources of PHCZs in the soil was conducted, revealing the diversity of PHCZs sources. Potential toxic effects associated with the levels of PHCZs were evaluated via the toxic equivalency (TEQ) approach, and the TEQs of PHCZs (TEQPHCZs) were in the range of 2.24-14.06 pg TEQ/g dw. Notwithstanding the 1368-CCZ with a low concentration level, the mean contribution to TEQPHCZs was up to 24.24%, preceded only by 36-CCZ (39.69%), showing the congeners with low concentration also may pose potential risks to the environment. Partial PHCZs congeners (2-BCZ, 3-BCZ, 36-CCZ, 136-BCZ, and 2367-BCZ) showed significant correlations (r = 0.45-0.63, p < 0.05) with the total organic carbon (TOC). Significant correlations were shown between PHCZ congeners replaced by halogens of the same species and quantity (r = 0.40-0.99, p < 0.01). In view of the fact that the high concentration level of PHCZs in the soil and their source diversity, more environmental monitoring and risk assessments of PHCZs should be of particular concern.


Asunto(s)
Contaminantes del Suelo , Contaminantes Químicos del Agua , Carbazoles , China , Monitoreo del Ambiente , Granjas , Suelo , Contaminantes Químicos del Agua/análisis
12.
Am J Drug Alcohol Abuse ; 47(5): 638-648, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34325579

RESUMEN

Background: Mind-body exercise is used for the rehabilitation of individuals with methamphetamine use disorder (MUD). Attention bias to substances is an important index of MUD. However, whether a mind-body exercise intervention can decrease attention bias is unclear.Objective: This study aimed to test the effect of a four-week Tai Chi (a Chinese traditional mind-body exercise) exercise program on the attention bias of individuals with MUD.Methods: Thirty-two men with MUD and without Tai Chi practice experience were recruited and randomly assigned to either a Tai Chi exercise group or a control group. The Tai Chi group received four-week Tai Chi training, while the control group engaged in daily exercise (including radio gymnastics and Jianxincao, two kinds of free-hand exercises). During a drug-related Stroop task, participants were instructed to respond to the color of the word ignoring the word type (drug-related or neutral words). The reaction time and d' (the index of sensitivity) were measured.Results: The participants showed attention bias to substance cues; the reaction time was slower for drug-related words than for neutral words (p < .05). After the Tai Chi intervention, the Tai Chi group showed a faster reaction time (ps < .05) and a smaller d' (ps < .05) than the baseline across all the word types. In contrast, the control group showed no differences (ps > .05).Conclusion: Four-week Tai Chi intervention reduced sensitivity and attentional bias to drug-related cues in individuals with MUD, suggesting that mind-body exercise might enhance recovery from MUD via attention control.


Asunto(s)
Trastornos Relacionados con Anfetaminas/terapia , Terapia por Ejercicio/psicología , Taichi Chuan/psicología , Adulto , Sesgo Atencional , Ansia , Señales (Psicología) , Humanos , Masculino , Metanfetamina , Persona de Mediana Edad , Tiempo de Reacción , Test de Stroop
13.
Neuroscience ; 458: 133-140, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33359653

RESUMEN

Deficits in the anticipation and experience of affective events represent a key risky factor for a variety of mental disorders, such as anxiety and depression. Here, we examined temporal dynamics underlying the modulations of the aversive mood state on neural responses of anticipating and perceiving affective pictures. Participants were asked to perform an affective cueing paradigm in both threat and safe contexts. In the task, a cue (S1) signaled the subsequent presentation of positive/negative event (e.g., happy or fearful faces) as an affective target stimulus (S2), and participants were instructed to indicate their subjective feelings in response to the target stimuli while electroencephalography (EEG) was recording. Our findings revealed that threat context compared with the safe context attenuated the contingent negative variation (CNV) responses to the cues of positive expressions, and decreased differential late positive potential (LPP) responses to the perception of negative and positive events. These findings suggest that aversive mood dampens the anticipation of positive events and inhibits the elaboration of negative events. The current findings do not only advance our understanding on the temporal characteristics of affective anticipation and experience but also have implications on the emotional deficits across various mental disorders characterized by chronic mood disturbances.


Asunto(s)
Afecto , Potenciales Evocados , Electroencefalografía , Emociones , Humanos , Percepción
14.
Iran J Public Health ; 50(10): 1944-1952, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35223561

RESUMEN

BACKGROUND: Rapid maxillary expansion (RME) is the standard treatment for correcting lateral maxillary defects commonly used in orthodontics. It is the most effective approach to increase maxillary width in clinical practice. At present, there are few studies on the level of molecular biology of periodontal tissue remodeling during RME. We aimed to investigate changes in matrix metalloproteinase (MMP)-8, interleukin (IL)-6 and tumor necrosis factor (TNF)-αin gingival crevicular fluid during RME. METHODS: Patients admitted to Department of Stomatology, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar, Heilongjiang Province, China between Dec 2016 and Dec 2018 were enrolled, and randomly divided into the observation group (76 cases) and control group (62 cases). Periodontal clinical indicators were recorded. Gingival crevicular fluid was collected and the periodontal clinical indicators were recorded. The levels of MMP-8, IL-6 and TNF-α were determined by ELISA, and the contents of the two groups were compared. RESULTS: The plaque index of the observation group was significantly higher than that of the baseline T0 (P< 0.05) from T4, and the increase in the control group started from T5. The general clinical data of the two groups showed that the white blood cell count of the observation group was higher than that of the control group. The levels of MMP-8, IL-6 and TNF-α were the highest at T2, followed by T3, and gradually decreased at T4, and T5, and the differences were significant (P<0.05). CONCLUSION: The changes in levels of MMP-8, IL-6 and TNF-α in adolescent patients during RME were related to the remodeling of periodontal tissue after RME.

15.
Heliyon ; 5(6): e01849, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31338443

RESUMEN

This paper analyzes the impact of the opening of an Intercity EUM (Electric Multiple Units) line, Guangzhou-Zhuhai Intercity Mass Rapid Transit, on GDP and population. By constructing the difference-in-difference (DID) model for whole 24 counties in Zhongshan of China, we found that with the opining of Intercity EMU, GDP growth and population inflow of the counties with Intercity EMU stations are significantly higher than those of without stations. Based on the Sharp Regression Discontinuity (SRD) Approach, we found that with the opining of Intercity EMU, the ratio of Guangzhou's GDP to that of other regions has obviously expanded, thus the opening of Intercity EMU has obviously widened the disparity of regional economic scale.

17.
Huan Jing Ke Xue ; 37(4): 1295-305, 2016 Apr 15.
Artículo en Chino | MEDLINE | ID: mdl-27548949

RESUMEN

Totally 128 surficial sediments samples were collected from the coastal wetlands, northeastern Hainan Island and analyzed for their concentrations of 14 elements including Al2O3, Fe2O3, MnO, Cu, Ni, Sr, Zn, V, Pb, Cr, Zr, As, Cd and Hg, TOC and grain sizes. The mean concentrations of trace metals V, Cr, Ni, Cu, Zn, As, Pb, Cd and Hg were (40.13 +/- 32.65), (35.92 +/- 26.90), (13.03 +/- 11.46), (11.56 +/- 10.27)-, (48.75 +/- 27.00), (5.48 +/- 1.60), ( 18.70 +/- 8.66), (0.054 +/- 0.045 ), (0.050 +/- 0.050) microg x g(-1), respectively, which were much lower than those in Pearl River Estuary, Yangzi River Estuary, Bohai Bay, upper crust and average shale. The average concentrations of Sr and Zr were much higher, reaching up to (1253.60 +/- 1649.58) microg x g(-1) and (372.40 +/- 516.49) microg x g(-1), respectively. The spatial distribution patterns of Al2O3, Fe2O3, MnO, Cu, Ni, Zn, V, Pb, Cr, Cd and Hg concentrations were the same as each other except for those of As, Sr and Zr. Generally, relatively high concentrations of these elements only appeared in the Haikou Bay, Nandu estuary, Dongzhai Harbor, Qinglan Harbor and Xiaohai in study area. The factor analysis revealed that the trace elements Al2O3 Fe2O3, MnO, Cu, Ni, Zn, V, Pb, Cr and part of Hg were mainly originated from the rock material by natural weathering processes, while the Cd and a part of Hg were from the biological source controlled by TOC. As and part of MnO were influenced by anthropogenic source, especially by aquacultures. Zr and some MnO were derived from heavy minerals dominated by the coarse grain of sediments. In contrast to the ERL, ERM and the results of enrichment factors (EF) , the environment of study area was good in general and the degree of contamination by trace elements was low on the whole. However, there are still some places where anthropogenic input have caused serious enrichments of trace elements and the occasional adverse effect on benthic organism induced by Ni could probably occur in 22% areas of all the sampling stations.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Humedales , China , Estuarios , Islas , Metales Pesados/análisis , Ríos
18.
Angew Chem Int Ed Engl ; 55(25): 7161-5, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27159245

RESUMEN

A recent technological trend in the field of electrochemical energy storage is to integrate energy storage and electrochromism functions in one smart device, which can establish efficient user-device interactions based on a friendly human-readable output. This type of newly born energy storage technology has drawn tremendous attention. However, there is still plenty of room for technological and material innovation, which would allow advancement of the research field. A prototype Al-tungsten oxide electrochromic battery with interactive color-changing behavior is reported. With the assistance of trace amount of H2 O2 , the battery exhibits a specific capacity almost seven times that for the reported electrochromic batteries, up to 429 mAh g(-1) . Fast decoloration of the reduced tungsten oxide affords a very quick charging time of only eight seconds, which possibly comes from an intricate combination of structure and valence state changes of tungsten oxide. This unique combination of features may further advance the development of smart energy storage devices with suitability for user-device interactions.

19.
J Am Chem Soc ; 137(40): 13200-8, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26393380

RESUMEN

The strong interest in macroscopic graphene and/or carbon nanotube (CNT) fiber has highlighted that anisotropic nanostructured materials are ideal components for fabricating fiber assemblies. Prospectively, employing two-dimensional (2D) crystals or nanosheets of functionality-rich transition metal oxides would notably enrich the general knowledge for desirable fiber constructions and more importantly would greatly broaden the scope of functionalities. However, the fibers obtained up to now have been limited to carbon-related materials, while those made of 2D crystals of metal oxides have not been achieved, probably due to the intrinsically low mechanical stiffness of a molecular sheet of metal oxides, which is only few hundredths of that for graphene. Here, using 2D titania sheets as an illustrating example, we present the first successful fabrication of macroscopic fiber of metal oxides composed of highly aligned stacking sheets with enhanced sheet-to-sheet binding interactions. Regardless of the intrinsically weak Ti-O bond in molecular titania sheets, the optimal fiber manifested mechanical performance comparable to that documented for graphene or CNTs. This work provided important hints for devising optimized architecture in macroscopic assemblies, and the rich functionalities of titania promises fibers with limitless promise for a wealth of innovative applications.

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