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1.
Plant Cell Rep ; 42(12): 1891-1906, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37743376

RESUMEN

KEY MESSAGE: The study of the origin, evolution, and diversification of the wall-associated kinase gene family in plants facilitates their functional investigations in the future. Wall-associated kinases (WAKs) make up one subfamily of receptor-like kinases (RLKs), and function directly in plant cell elongation and responses to biotic and abiotic stresses. The biological functions of WAKs have been extensively characterized in angiosperms; however, the origin and evolutionary history of the WAK family in green plants remain unclear. Here, we performed a comprehensive analysis of the WAK family to reveal its origin, evolution, and diversification in green plants. In total, 1061 WAK genes were identified in 37 species from unicellular algae to multicellular plants, and the results showed that WAK genes probably originated before bryophyte differentiation and were widely distributed in land plants, especially angiosperms. The phylogeny indicated that the land plant WAKs gave rise to five clades and underwent lineage-specific expansion after species differentiation. Cis-acting elements and expression patterns analyses of WAK genes in Arabidopsis and rice demonstrated the functional diversity of WAK genes in these two species. Many gene gains and losses have occurred in angiosperms, leading to an increase in the number of gene copies. The evolutionary trajectory of the WAK family during polyploidization was uncovered using Gossypium species. Our results provide insights into the evolution of WAK genes in green plants, facilitating their functional investigations in the future.


Asunto(s)
Arabidopsis , Plantas , Plantas/genética , Genes de Plantas/genética , Arabidopsis/genética , Familia de Multigenes
2.
J Clin Apher ; 38(4): 491-494, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36579441

RESUMEN

Pemphigus vulgaris (PV) is a chronic, mucocutaneous, autoimmune bullous disease. Double filtration plasmapheresis (DFPP) may be effective when PV fails to be controlled by conventional corticosteroid treatment. The patient was a 64-year-old man with erythema, blisters, and erosions on his head, face, mouth, trunk, limbs, and scrotum for over a month. He was diagnosed with severe PV, and the original rash area continued to expand after treatment with systemic corticosteroids, immunosuppressants, and intravenous immunoglobulin, with massive exudate and ≥5 new blisters and macules still occurring daily. Subsequently, the patient completed three sessions of DFPP. After the first DFPP, the original erosion surface exudate was significantly reduced and gradually healed. After the second DFPP, the erosion area and exudate increased compared with the previous one. After the third DFPP, the rash did not improve further and had a tendency to continue to progress. During the entire three sessions of DFPP, the patient had new blisters and bullae on his limbs every day. The Nikolsky's sign of the limbs turned negative at the initial stage, and then the trunk and limbs Nikolsky's sign became positive again. The titer of autoantibodies did not decrease significantly after the plasmapheresis. The patient eventually died of secondary lung infection and septic shock. The efficacy of DFPP in this patient with refractory severe PV was poor.


Asunto(s)
Enfermedades Autoinmunes , Exantema , Pénfigo , Masculino , Humanos , Persona de Mediana Edad , Pénfigo/terapia , Vesícula/terapia , Plasmaféresis , Autoanticuerpos , Enfermedades Autoinmunes/terapia , Corticoesteroides , Exantema/terapia , Filtración
3.
Int J Mol Sci ; 24(11)2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37298464

RESUMEN

Salinity is a major abiotic stress that restricts cotton growth and affects fiber yield and quality. Although studies on salt tolerance have achieved great progress in cotton since the completion of cotton genome sequencing, knowledge about how cotton copes with salt stress is still scant. S-adenosylmethionine (SAM) plays important roles in many organelles with the help of the SAM transporter, and it is also a synthetic precursor for substances such as ethylene (ET), polyamines (PAs), betaine, and lignin, which often accumulate in plants in response to stresses. This review focused on the biosynthesis and signal transduction pathways of ET and PAs. The current progress of ET and PAs in regulating plant growth and development under salt stress has been summarized. Moreover, we verified the function of a cotton SAM transporter and suggested that it can regulate salt stress response in cotton. At last, an improved regulatory pathway of ET and PAs under salt stress in cotton is proposed for the breeding of salt-tolerant varieties.


Asunto(s)
S-Adenosilmetionina , Tolerancia a la Sal , Tolerancia a la Sal/genética , Estrés Salino , Estrés Fisiológico/genética , Gossypium/genética , Regulación de la Expresión Génica de las Plantas
4.
J Exp Bot ; 73(3): 711-726, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-34636403

RESUMEN

In plants, glucose (Glc) plays important roles, as a nutrient and signal molecule, in the regulation of growth and development. However, the function of Glc in fiber development of upland cotton (Gossypium hirsutum) is unclear. Here, using gas chromatography-mass spectrometry (GC-MS), we found that the Glc content in fibers was higher than that in ovules during the fiber elongation stage. In vitro ovule culture revealed that lower Glc concentrations promoted cotton fiber elongation, while higher concentrations had inhibitory effects. The hexokinase inhibitor N-acetylglucosamine (NAG) inhibited cotton fiber elongation in the cultured ovules, indicating that Glc-mediated fiber elongation depends on the Glc signal transduced by hexokinase. RNA sequencing (RNA-seq) analysis and hormone content detection showed that 150mM Glc significantly activated brassinosteroid (BR) biosynthesis, and the expression of signaling-related genes was also increased, which promoted fiber elongation. In vitro ovule culture clarified that BR induced cotton fiber elongation in a dose-dependent manner. In hormone recovery experiments, only BR compensated for the inhibitory effects of NAG on fiber elongation in a Glc-containing medium. However, the ovules cultured with the BR biosynthetic inhibitor brassinazole and from the BR-deficient cotton mutant pag1 had greatly reduced fiber elongation at all the Glc concentrations tested. This demonstrates that Glc does not compensate for the inhibition of fiber elongation caused by BR biosynthetic defects, suggesting that the BR signaling pathway works downstream of Glc during cotton fiber elongation. Altogether, our study showed that Glc plays an important role in cotton fibre elongation, and crosstalk occurs between Glc and BR signaling during modulation of fiber elongation.


Asunto(s)
Brasinoesteroides , Fibra de Algodón , Brasinoesteroides/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucosa/metabolismo , Gossypium/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Chemistry ; 28(31): e202104523, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35224788

RESUMEN

Novel and stringent automotive exhaust gas emissions standards are urgently needed to counter the problems posed by the worsening global climate and environment. However, the traditional cordierite-based honeycomb ceramics substrates with ultimate pore density have seriously restricted the establishment of new emission standards. Herein, we introduce a novel robust substrate with tailored volume-specific surface area and low heat capacity. This substrate employs the synergy of high-strength ceramic fibers and ultrathin TiO2 nanosheets. The micro-sized fibers provide support to ensure structural strength during the catalytic reaction, while the nanosheets play the dual role of connecting the fibers and providing a high surface area for catalyst immobilization. The new three-dimensional (3D) microarchitecture exhibits a high volume-specific surface area of 3.59×104  cm2 /cm3 , a compressive strength of 2.01 MPa, and remarkable stability after high-speed air erosion at 800 °C. The honeycomb-like structure exhibit low resistance to gas flow. Furthermore, after loading with Pt and Pd nanoparticles, the composite 3D microarchitecture delivered an excellent catalytic performance and prominent structural stability, with a super low light-off temperature of 150 °C. The outstanding mechanical and thermal stability and the high surface area and light-off temperature of the new substrate indicate its potential for use as a highly efficient catalytic carrier to meet the next-generation auto emissions standards.

6.
Chemistry ; 28(11): e202102787, 2022 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-34961998

RESUMEN

Silicoaluminophosphate zeolite (SAPO-34) has been attracting increasing attention due to its excellent form selection and controllability in the chemical industry, as well as being one of the best industrial catalysts for methanol-to-olefin (MTO) reaction conversion. However, as a microporous molecular sieve, SAPO-34 easily generates carbon deposition and rapidly becomes inactivated. Therefore, it is necessary to reduce the crystal size of the zeolite or to introduce secondary macropores into the zeolite crystal to form a hierarchical structure in order to improve the catalytic effect. In this review, the synthesis methods of conventional SAPO-34 molecular sieves, hierarchical SAPO-34 molecular sieves and nanosized SAPO-34 molecular sieves are introduced, and the properties of the synthesized SAPO-34 molecular sieves are described, including the phase, morphology, pore structure, acid source, and catalytic performance, in particular with respect to the synthesis of hierarchical SAPO-34 molecular sieves. We hope that the review can provide guidance to the preparation of the SAPO-34 catalysts, and stimulate the future development of high-performance hierarchical SAPO-34 catalysts to meet the growing demands of the material and chemical industries.

7.
Inorg Chem ; 61(7): 3263-3273, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35133813

RESUMEN

The modifications of local structure in solid solution are a crucial step to regulate the photoluminescence properties of rare-earth ion-based phosphors. However, the structural diversity of host matrices and the uncertain occupation of activators make it challenging to obtain phosphors with both high stability and tailored emission. Herein, We synthesized a series of ß-Ca3(PO4)2-type Ca8ZnGa(1-x)Lax(PO4)7:Eu2+ solid solution phosphors by design. By modifying the Ga/La ratio, controllable regulation of the emission spectrum and thermal stability of the phosphors can be achieved at the same time. The introduction of La3+ can regulate the crystal field splitting strength of the Eu2+ activators, causing redshifts in the emission spectrum while increasing Ga3+ content will lead to enhanced energy transfer between the oxygen vacancy and Eu2+, as well as improved thermal stability. Through local structure modification, the spectrum and thermal stability of phosphors can be facilely tuned. The results indicate that this series of phosphors have versatile potentials in various applications.

8.
Molecules ; 27(15)2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35897927

RESUMEN

The high price of noble metal resources limits its commercial application and stimulates the potential for developing new catalysts that can replace noble metal catalysts. Tungsten-based catalysts have become the most important substitutes for noble metal catalysts because of their rich resources, friendly environment, rich valence and better adsorption enthalpy. However, some challenges still hinder the development of tungsten-based catalysts, such as limited catalytic activity, instability, difficult recovery, and so on. At present, the focus of tungsten-based catalyst research is to develop a satisfactory material with high catalytic performance, excellent stability and green environmental protection, mainly including tungsten atomic catalysts, tungsten metal nanocatalysts, tungsten-based compound nanocatalysts, and so on. In this work, we first present the research status of these tungsten-based catalysts with different sizes, existing forms, and chemical compositions, and further provide a basis for future perspectives on tungsten-based catalysts.


Asunto(s)
Metales , Tungsteno , Catálisis , Tungsteno/química
9.
Molecules ; 26(11)2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34071526

RESUMEN

Developing a porous separation membrane that can efficiently separate oil-water emulsions still represents a challenge. In this study, nanofiber membranes with polydopamine clusters polymerized and embedded on the surface were successfully constructed using a solution blow-spinning process. The hierarchical surface structure enhanced the selective wettability, superhydrophilicity in air (≈0°), and underwater oleophobicity (≈160.2°) of the membrane. This membrane can effectively separate oil-water emulsions, achieving an excellent permeation flux (1552 Lm-2 h-1) and high separation efficiency (~99.86%) while operating only under the force of gravity. When the external driving pressure was increased to 20 kPa, the separation efficiency hardly changed (99.81%). However, the permeation flux significantly increased to 5894 Lm-2 h-1. These results show that the as-prepared polydopamine nanocluster-embedded nanofiber membrane has an excellent potential for oily wastewater treatment applications.

10.
BMC Plant Biol ; 20(1): 395, 2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32854609

RESUMEN

BACKGROUND: Fiber quality is an important economic trait of cotton, and its improvement is a major goal of cotton breeding. To better understand the genetic mechanisms responsible for fiber quality traits, we conducted a genome-wide association study to identify and mine fiber-quality-related quantitative trait loci (QTLs) and genes. RESULTS: In total, 42 single nucleotide polymorphisms (SNPs) and 31 QTLs were identified as being significantly associated with five fiber quality traits. Twenty-five QTLs were identified in previous studies, and six novel QTLs were firstly identified in this study. In the QTL regions, 822 genes were identified and divided into four clusters based on their expression profiles. We also identified two pleiotropic SNPs. The SNP locus i52359Gb was associated with fiber elongation, strength, length and uniformity, while i11316Gh was associated with fiber strength and length. Moreover, these two SNPs were nonsynonymous and located in genes Gh_D09G2376 and Gh_D06G1908, respectively. RT-qPCR analysis revealed that these two genes were preferentially expressed at one or more stages of cotton fiber development, which was consistent with the RNA-seq data. Thus, Gh_D09G2376 and Gh_D06G1908 may be involved in fiber developmental processes. CONCLUSIONS: The findings of this study provide insights into the genetic bases of fiber quality traits, and the identified QTLs or genes may be applicable in cotton breeding to improve fiber quality.


Asunto(s)
Fibra de Algodón/análisis , Genes de Plantas , Estudio de Asociación del Genoma Completo , Gossypium/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Gossypium/anatomía & histología , Gossypium/fisiología
11.
Nanotechnology ; 31(30): 305301, 2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32241006

RESUMEN

In this study, a transparent particle-free reactive silver ink was used to fabricate conductive patterns on a flexible substrate. Thermal annealing and plasma irradiation at low temperature were utilized to improve the conductivity of the as-printed patterns. The effects of sintering process parameters on the microstructure and resistivity of the patterns were investigated. Under the optimized processing conditions, the resistivity of the pattern reached 1.2 × 10 -7 Ω · m by thermal sintering, while it was 8 × 10 -8 Ω · m after plasma sintering. Combined with these two sintering techniques, the resistivity was reduced to 6 × 10-8 Ω · m, close to that of bulk silver. This work provides an alternative solution for the fabrication of highly conductive feature patterns on common flexible substrates.

12.
Molecules ; 25(3)2020 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-32012682

RESUMEN

The fabrication and luminescent performance of novel phosphors Na2YMg2V3O12:Dy3+ were investigated by a conventional solid-state reaction method. Under near-UV light, the Na2YMg2V3O12 host self-activated and released a broad emission band (400-700 nm, with a peak at 524 nm) ascribable to charge transfer in the (VO4)3- groups. Meanwhile, the Na2YMg2V3O12:Dy3+ phosphors emitted bright yellow light within both the broad emission band of the (VO4)3- groups and the sharp peaks of the Dy3+ ions at 490, 582, and 663 nm at a quenching concentration of 0.03 mol. The emission of the as-prepared Na2YMg2V3O12:Dy3+ phosphors remained stable at high temperatures. The obtained phosphors, commercial Y2O3:Eu3+ red phosphors, and BaMgAl10O17:Eu2+ blue phosphors were packed into a white light-emitting diode (WLED) device with a near-UV chip. The designed WLED emitted bright white light with good chromaticity coordinates (0.331, 0.361), satisfactory color rendering index (80.2), and proper correlation to a color temperature (7364 K). These results indicate the potential utility of Na2YMg2V3O12:Dy3+ phosphor as a yellow-emitting phosphor in solid-state illumination.


Asunto(s)
Disprosio/química , Luminiscencia , Sustancias Luminiscentes/química , Magnesio/química , Óxidos/química , Sodio/química , Vanadio/química
13.
Plant Biotechnol J ; 17(4): 762-775, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30220108

RESUMEN

Upland cotton (Gossypium hirsutum) is the world's largest source of natural fibre and dominates the global textile industry. Hybrid cotton varieties exhibit strong heterosis that confers high fibre yields, yet the genome-wide effects of artificial selection that have influenced Upland cotton during its breeding history are poorly understood. Here, we resequenced Upland cotton genomes and constructed a variation map of an intact breeding pedigree comprising seven elite and 19 backbone parents. Compared to wild accessions, the 26 pedigree accessions underwent strong artificial selection during domestication that has resulted in reduced genetic diversity but stronger linkage disequilibrium and higher extents of selective sweeps. In contrast to the backbone parents, the elite parents have acquired significantly improved agronomic traits, with an especially pronounced increase in the lint percentage. Notably, identify by descent (IBD) tracking revealed that the elite parents inherited abundant beneficial trait segments and loci from the backbone parents and our combined analyses led to the identification of a core genomic segment which was inherited in the elite lines from the parents Zhong 7263 and Ejing 1 and that was strongly associated with lint percentage. Additionally, SNP correlation analysis of this core segment showed that a non-synonymous SNP (A-to-G) site in a gene encoding the cell wall-associated receptor-like kinase 3 (GhWAKL3) protein was highly correlated with increased lint percentage. Our results substantially increase the valuable genomics resources available for future genetic and functional genomics studies of cotton and reveal insights that will facilitate yield increases in the molecular breeding of cotton.


Asunto(s)
Genoma de Planta/genética , Genómica , Gossypium/genética , Productos Agrícolas , Domesticación , Sitios Genéticos , Genotipo , Desequilibrio de Ligamiento , Linaje , Fenotipo , Fitomejoramiento
14.
Theor Appl Genet ; 132(7): 1991-2002, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30982110

RESUMEN

KEY MESSAGE: A genome-wide associated study identified six novel QTLs for lint percentage. Two candidate genes underlying this trait were also detected. Increasing lint percentage (LP) is a core goal of cotton breeding. To better understand the genetic basis of LP, a genome-wide association study (GWAS) was conducted using 276 upland cotton accessions planted in multiple environments and genotyped with a CottonSNP63K array. After filtering, 10,660 high-quality single-nucleotide polymorphisms (SNPs) were retained. Population structure, principal component and neighbor-joining phylogenetic tree analyses divided the accessions into two subpopulations. These results along with linkage disequilibrium decay indicated accessions were not highly structured and exhibited weak relatedness. GWAS uncovered 23 polymorphic SNPs and 15 QTLs significantly associated with LP, with six new QTLs identified. Two candidate genes, Gh_D05G0313 and Gh_D05G1124, both contained one significant SNP, highly expressed during ovule and fiber development stages, implying that the two genes may act as the most promising regulators of LP. Furthermore, the phenotypic value of LP was found to be positively correlated with the number of favorable SNP alleles. These favorable alleles for LP identified in the study may be useful for improving lint yield.


Asunto(s)
Fibra de Algodón , Gossypium/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Estudios de Asociación Genética , Genética de Población , Genoma de Planta , Genotipo , Desequilibrio de Ligamiento , Fenotipo , Fitomejoramiento
15.
Nanotechnology ; 30(15): 155701, 2019 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-30641511

RESUMEN

We design a facile approach to prepare a bimetallic transition-metal-sulphide-based 3D hierarchically-ordered porous electrode based on bimetallic metal-organic frameworks (Ni-Co-MOFs) by using confinement growth and in-situ sulphurisation techniques. In the novel resulting architectures, Ni-Co-S nanoparticles are confined in bowknot-like and flower-like carbon networks and are mechanically isolated but electronically well-connected, where the carbon networks with a honeycomb-like feature facilitate electron transfer with uninterrupted conductive channels from all sides. Moreover, these hierarchically-ordered porous structures together with internal voids can accommodate the volume expansion of the embedded Ni-Co-S nanoparticles. The pseudocapacitive behaviours displayed in the NCS@CBs and NCS@CFs occupied a significant portion in the redox processes. Because of these merits, both the as-built bowknot and flower networks show excellent electrochemical properties for lithium storage with superior rate capability and robust cycling stability (994 mAh g-1 for NCS@CBs and 888 mAh g-1 for NCS@CFs after 200 cycles). This unique 3D hierarchically-ordered structural design is believed to hold great potential applications in propagable preparation of carbon networks teamed up with sulphide nanocrystals for high energy storage.

16.
Molecules ; 24(7)2019 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-30987075

RESUMEN

The development of white-light-emitting diodes (w-LEDs) makes it meaningful to develop novel high-performance phosphors excited by blue light. Herein, BiOCl:Pr3+ green-yellow phosphors were prepared via a high-temperature solid-state reaction method. The crystal structure, luminescent properties, lifetime, thermal quenching behavior, and quantum yield were studied in detail. The BiOCl:Pr3+ phosphors presented several emission peaks located in green and red regions, under excitation at 453 nm. The CIE coordinates could be tuned along with the changed doping concentration with fair luminescence efficiency. The results also indicated that the optimized doping concentration of Pr3+ ions was at x = 0.0075 because of the concentration quenching behavior resulting from an intense exchange effect. When the temperature reached 150 °C, the intensity of the emission peak at 495 nm could remain at 78% of that at room temperature. The activation energy of 0.20 eV also confirmed that the BiOCl:Pr3+ phosphor exhibited good thermal stability. All these results indicate that the prepared products have potential to be used as a high-performance green-yellow-light-emitting phosphor for blue-light-based w-LEDs.


Asunto(s)
Luminiscencia , Sustancias Luminiscentes/química , Sustancias Luminiscentes/síntesis química , Modelos Moleculares , Termodinámica , Difracción de Rayos X
18.
Int J Mol Sci ; 19(3)2018 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-29517986

RESUMEN

The SWEET (sugars will eventually be exported transporters) proteins are sugar efflux transporters containing the MtN3_saliva domain, which affects plant development as well as responses to biotic and abiotic stresses. These proteins have not been functionally characterized in the tetraploid cotton, Gossypium hirsutum, which is a widely cultivated cotton species. In this study, we comprehensively analyzed the cotton SWEET gene family. A total of 55 putative G. hirsutumSWEET genes were identified. The GhSWEET genes were classified into four clades based on a phylogenetic analysis and on the examination of gene structural features. Moreover, chromosomal localization and an analysis of homologous genes in Gossypium arboreum, Gossypium raimondii, and G. hirsutum suggested that a whole-genome duplication, several tandem duplications, and a polyploidy event contributed to the expansion of the cotton SWEET gene family, especially in Clade III and IV. Analyses of cis-acting regulatory elements in the promoter regions, expression profiles, and artificial selection revealed that the GhSWEET genes were likely involved in cotton developmental processes and responses to diverse stresses. These findings may clarify the evolution of G. hirsutum SWEET gene family and may provide a foundation for future functional studies of SWEET proteins regarding cotton development and responses to abiotic stresses.


Asunto(s)
Evolución Molecular , Gossypium/genética , Proteínas de Transporte de Monosacáridos/genética , Proteínas de Plantas/genética , Estrés Fisiológico , Cromosomas de las Plantas/genética , Duplicación de Gen , Gossypium/clasificación , Gossypium/fisiología , Proteínas de Transporte de Monosacáridos/metabolismo , Familia de Multigenes , Filogenia , Proteínas de Plantas/metabolismo , Ploidias , Regiones Promotoras Genéticas
19.
Inorg Chem ; 56(3): 1144-1151, 2017 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-28112918

RESUMEN

Codoping with Li+ is a prevalent strategy to improve the optical efficiency of luminescent materials, while the mechanisms of enhancement are still ambiguous. Herein, we delineate the major ways by which Li+ enhanced the emission of orthophosphate phosphor KMg4(PO4)3:Eu2+ and quantify the relative contributions of each mechanism. Results from X-ray diffraction, scanning electron microscopy, and steady-state and time-resolved fluorescence spectroscopies show that the 3.8-fold increase in emission intensity caused by optimized Li+ doping was attributed to flux effect (∼30.84%), crystal-field splitting (∼5.30%), and a reduction in concentration quenching (∼63.86%), respectively. The as-synthesized materials also show excellent thermal stability and an increased internal quantum efficiency of 84.02% compared with 53.13% of nondoped phosphors. The white light emitting diodes employing KMg4(PO4)3:Eu2+,Li+ as a blue-emitting component exhibit superior electroluminescence properties. The above results demonstrate that introducing Li+ ions can obviously enhance the luminescence efficiency of KMg4(PO4)3:Eu2+ phosphor.

20.
Nanotechnology ; 28(28): 285703, 2017 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-28574853

RESUMEN

Transparent and flexible electrodes on cost effective plastic substrates for wearable electronics have attract great attention recently. Due to the conductivity and flexibility in network form, metal nanowire is regarded as one of the most promising candidates for flexible electrode fabrication. Prior to application, low temperature joining of nanowire processes are required to reduce the resistance of electrodes and simultaneously maintain the dimensionality and uniformity of those nanowires. In the present work, we presented an innovative, robust and cost effective method to minimize the heat effect to plastic substrate and silver nanowires which allows silver nanowire electrodes been directly written on polycarbonate substrate and sintered by different electrolyte solutions at room temperature or near. It has been rigorously demonstrated that the resistance of silver nanowire electrodes has been reduced by 90% after chemical sintering at room temperature due to the joining of silver nanowires at junction areas. After ∼1000 bending cycles, the measured resistance of silver nanowire electrode was stable during both up-bending and down-bending states. The changes of silver nanowires after sintering were characterized using x-ray photoelectron spectroscopy and transmission electron microscopy and a sintering mechanism was proposed and validated. This direct-written silver nanowire electrode with good performance has broad applications in flexible electronics fabrication and packaging.

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