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A series of color-tunable warm white-emitting phosphors Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+,Eu3+ were synthesized and characterized for their crystal structure, luminescence properties, thermal stability, fluorescence decay and energy transfer mechanism. The results show that the optimal excitation wavelength and doping concentration of Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+ phosphor are 350 nm and 0.05 mol%, respectively, and its concentration quenching is mainly caused by the interaction between nearest neighbor ions. Under the excitation at 350 nm, the Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+,Eu3+ phosphor showed prominent emission peaks at 471 nm, 576 nm and 622 nm. The photoluminescence spectrum and lifetime decay curves confirmed the presence of Dy3+→Eu3+ energy transfer in Ca 3 Y(AlO) 3 (BO 3) 4. The phosphor of Ca 3 Y 0·85 (AlO) 3 (BO 3) 4 :0.05Dy3+,0.1Eu3+ exhibited remarkable thermal stability and could maintain 87.68% of the emission intensity at 150 °C. By adjusting the doping ratio of Dy3+ and Eu3+ ions, the CIE coordinates and the related color temperature of Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+,Eu3+ phosphors can be adjusted. The w-LED device packaged with Ca 3 Y 0·85 (AlO) 3 (BO 3) 4 :0.05Dy3+,0.1Eu3+ phosphor can emit warm-white light (Tc = 3284 K, Ra = 72.7). These results suggest that Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+,Eu3+ phosphor can provide a potential alternative for the warm w-LED market. [Display omitted] • Synthesis of Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+, Eu3+ phosphors was successful. • The energy transfer between Dy3+ and Eu3+ in Ca 3 Y(AlO) 3 (BO 3) 4 was studied. • Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+, Eu3+ co-doped phosphors display exceptional thermal stability. • The CCT and color coordinates of warm white Ca 3 Y(AlO) 3 (BO 3) 4 :Dy3+, Eu3+ phosphors can be modified. [ABSTRACT FROM AUTHOR]

A series of blue-to-white emitting Mg2Al4Si5O18: Eu2+, Mn2+ phosphors were synthesized via high-temperature solid-state method, and their luminescence properties were investigated in detail. Under near-ultraviolet (UV) light excitation of 365 nm, Eu2+-doped Mg2Al4Si5O18 exhibits a broad blue emission band peaked at 469 nm, and Mn2+-doped Mg2Al4Si5O18 shows a broad orange-red emission band near 600 nm. The energy transfer from Eu2+ to Mn2+ in Mg2Al4Si5O18 host matrix can be found, and the resonant type is demonstrated by a dipole-quadrupole mechanism. The emission hue can be tuned from blue (0.17, 0.17) to bluish green (0.22, 0.29) and finally to white (0.31, 0.33) by properly varying the ratio of Eu2+/Mn2+.The thermal quenching property of the sample was investigated, and the activation energy ΔE was estimated to be 0.30 eV. Additionally, the energy transfer critical distance between Eu2+ and Mn2+ was calculated. With appropriate tuning of activator content, the Mg2Al4Si5O18: Eu2+, Mn2+ phosphor may have potential application for UV light-emitting diodes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Porous FeCO3 microspheres were synthesized via a facile surfactant- and template-free hydrothermal process. The diameters of FeCO3 microspheres are about 20±5 µm. Each FeCO3 microsphere was self-assembled with a number of trilobed wheel-like subunits. The influence of preparation conditions, such as temperature, reaction time and content of urea on the phase composition and morphology were investigated. Based on time-dependent experiments, we proposed the possible formation mechanism for the self-assembled FeCO3 micro-spheres. After calcination at 650 °C, α-Fe2O3 derived from FeCO3 retained the original size and morphology of FeCO3. The prepared α-Fe2O3 with the novel microstructure shows wide potential application as photocatalysts. [ABSTRACT FROM AUTHOR]

Well-aligned TiO2 nanotube arrays were fabricated by anodizing Ti foil in viscous F containing organic electrolytes, and the crystal structure and morphology of the TiO2 nanotube array were characterized and analyzed by XRD, SEM, and TEM, respectively. The photocatalytic activity of the TiO2 nanotube arrays was evaluated in the photocatalytic (PC) and photoelectrocatalytic (PEC) degradation of methylene blue (MB) dye in different supporting solutions. The excellent performance of ca. 97% for color removal was reached after 90 min in the PEC process compared to that of PC process which indicates that a certain external potential bias favors the promotion of the electrode reaction rate on TiO2 nanotube array when it is under illumination. In addition, it is found that PEC process conducted in supporting solutions with lowpH and containing Cl is also beneficial to accelerate the degradation rate of MB. [ABSTRACT FROM AUTHOR]

Gossypium hirsutum L. is a worldwide economical crop; however, premature leaf senescence reduces its production and quality which is regulated by stresses, hormones, and genes. DNA binding with the one zinc finger (Dof) transcription factors (TFs) participate widely in plant development and responses to biotic and abiotic stresses, but there have been few reports of these TFs in cotton. Here, we perform a genome-wide study of G. Hirsutum L. Dof (GhDof) genes and analyze their phylogeny, duplication, and expression. In total, 114 GhDof genes have been identified and classified into nine subgroups (A, B1, B2.2, B2.1, C1, C2.1, C2.2, D1, and D2) based on phylogenetic analysis. An MCScanX analysis showed that the GhDof genes expanded due to segmental duplications. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that GhDofD9.6 was not only differentially expressed between CCRI10 (with premature senescence) and Liao4086 (without premature senescence) but also responded to salinity stress; GhDofA5.7, GhDofA7.4, GhDofA8.2, GhDof11.1, GhDofD7.2, and GhDofD11.3 significantly responded to cold (4 °C) stress. This work lays the foundation for further analysis of the function of GhDof genes in G. hirsutum, which will be helpful for improving the production and quality of cotton. [ABSTRACT FROM AUTHOR]

CCRI63, with the largest cultivated area among hybrids in China, is a successful promotion of elite upland cotton (Gossypium hirsutum L.) hybrid cultivar. We have constructed a detailed genomic variation map of CCRI63 by aligning whole-genome shotgun sequencing reads from CCRI63 to the TM-1 reference genome. Genomic single nucleotide polymorphism (SNP) and insertion-deletion (Indel) mutational hotspots were identified, most of which were located on chromosome D02, and associated with disease resistance and lipid glycosylation and modification. The density of heterozygous SNP sites showed 73 quantitative trait loci overlapped with peak intervals of high-density heterozygous SNPs, suggesting that the heterozygous sites in the peak are important for improvement of CCRI63 yield and fibre quality. To avoid loss of genetic components, unmapped reads were used for de novo assembly of the missing regions in the reference genome, and 153 novel functional genes were obtained. The large-scale genetic variation and novel functional genes identified in the CCRI63 genome can facilitate future gene-phenotype studies and provide an additional resource for the improvement of cotton. [ABSTRACT FROM AUTHOR]

Herein, a facile surfactant-free hydrothermal method assisted with coprecipitation has been explored in order to prepare size-controlled HAP nanorods, and the growth mechanism of HAP nanostructures has also been proposed. In this article, the size of the HAP crystallites, ranging from 40 to 1500 nm, were controlled by varying the reaction conditions. Likewise, the experimental conditions can be changed to alter the shapes of the HAP nanostructures from nanorods to nanobelts. Additionally, interesting optically properties were induced in nano-HAP by doping with rare earth elements. The samples doped with terbium and europium generated green and red orange emissions, respectively, under irradiation by blue light, which is popularly used for wound healing and skin disease treatment. Thus, the doped HAP nanocrystals through the surfactant-free method have potential applications in blue phototherapy and photodynamic therapy. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]