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Abstract Supported nanocatalysts are crucial for hydrogen production, yet their activity and stability are challenging to manage due to complex metal-support interfaces. Herein, we design Pt@ anatase&rutile-TiO2 with a strong-weak dual interface by modifying TiO2 using high-energy ball milling and in-situ reduction to vary surface energies. Experiments and density functional theory calculations reveal that the strong Pt-anatase TiO2 interface enhances hydrogen adsorption. In contrast, the weak Pt-rutile TiO2 interface facilitates hydrogen desorption, simultaneously preventing Pt agglomeration and increasing reaction rate. As a result, the tailored catalyst has a 529.3 mV overpotential at 1000 mA cm−2 in 0.5 M H2SO4, 0.69 times less than commercial Pt/C. It also possesses 8.8 times the mass activity of commercial Pt/C and maintains a low overpotential after 2000 cyclic voltammetry cycles, suggesting high activity and stability. This strong-weak dual interface engineering strategy shows potential for overall water splitting and proton exchange membrane water electrolyzer, advancing the design of efficient supported nanocatalysts.

SINA (Seven in absentia) E3 ligases are critical components of the ubiquitin-proteasome system (UPS). They are responsible for ubiquitination and are involved in numerous cellular processes. The functional mechanisms of SINAs have been extensively studied in a few angiosperms. However, our understanding of the origin and evolution of plant SINA genes remain limited. Here we performed a large-scale comprehensive analysis of SINA proteins from various plant lineages. The plant SINA family genes likely originated from a common ancestral gene prior to the divergence of bryophyte and gave rise to two clades. Within clade I, subsequent parallel innovations in lycophytes and ferns resulted in the formation of two branches. All SINA proteins contain an N-terminal cysteine-rich really interesting new gene (RING) domain for ubiquitination, two zinc-finger motifs, and a C-terminal domain required for substrate-binding and dimerization. The SINA genes gains and losses occurred in angiosperms, resulting in an increase in the number of gene copies in eudicots and monocots. The Gossypium genus SINAs showed a tendency for expansion via whole-genome duplication and polyploidy. Finally, global expression patterns revealed the functional diversification of SINA genes in developmental stage and response to hormones and abiotic stresses in Arabidopsis and rice. These findings provide an insight into the evolution and diversification of SINA E3 ligases in plants and enhance our understanding of the role they play in determining substrate specificity and environment stress adaptations in angiosperms.

Abstract 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.

Abstract With the increase in the use of electronic devices in many different environments, a need has arisen for an easily implemented method for the rapid, sensitive detection of liquids in the vicinity of electronic components. In this work, a high-performance power generator that combines carbon nanoparticles and TiO2 nanowires has been fabricated by sequential electrophoretic deposition (EPD). The open-circuit voltage and short-circuit current of a single generator are found to exceed 0.7 V and 100 μA when 6 μL of water was applied. The generator is also found to have a stable and reproducible response to other liquids. An output voltage of 0.3 V was obtained after 244, 876, 931, and 184 μs, on exposure of the generator to 6 μL of water, ethanol, acetone, and methanol, respectively. The fast response time and high sensitivity to liquids show that the device has great potential for the detection of small quantities of liquid. In addition, the simple easily implemented sequential EPD method ensures the high mechanical strength of the device. This compact, reliable device provides a new method for the sensitive, rapid detection of extraneous liquids before they can impact the performance of electronic circuits, particularly those on printed circuit board.

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.

Abstract A series of luminescent Ba0.79Al10.9O17.14:xEu (x = 0.005–0.12) phosphors were prepared by high-temperature solid-state reaction in air atmosphere. The coexistence of Eu2+ and Eu3+ was observed and verified by photoluminescence (PL) and photoluminescence excitation (PLE) spectra, X-ray photoelectron spectra (XPS), and diffuse reflection spectra. The band emission peaking at 430 nm was assigned to 4F65D–4F7 transition of Eu2+, and another four emissions peaking at 589, 619, 655, and 704 nm were attributed to 4F–4F transitions of 5D0–7F J (J = 1, 2, 3, 4) of Eu3+. The related mechanism of self-reduction was discussed in detail. The color of the Ba0.79Al10.9O17.14:xEu phosphors could be shifted from blue (0.23, 0.10) to red (0.42, 0.27) by doping Li+ ions, and the temperature dependence properties were investigated.

Histone modification is an important epigenetic modification that controls gene transcriptional regulation in eukaryotes. Histone methylation is accomplished by histone methyltransferase and can occur on two amino acid residues, arginine and lysine. JumonjiC (JmjC) domain-containing histone demethylase regulates gene transcription and chromatin structure by changing the methylation state of the lysine residue site and plays an important role in plant growth and development. In this study, we carried out genome-wide identification and comprehensive analysis of JmjC genes in the allotetraploid cotton species Gossypium hirsutum. In total, 50 JmjC genes were identified and in G. hirsutum, and 25 JmjC genes were identified in its two diploid progenitors, G. arboreum and G. raimondii, respectively. Phylogenetic analysis divided these JmjC genes into five subfamilies. A collinearity analysis of the two subgenomes of G. hirsutum and the genomes of G. arboreum and G. raimondii uncovered a one-to-one relationship between homologous genes of the JmjC gene family. Most homologs in the JmjC gene family between A and D subgenomes of G. hirsutum have similar exon-intron structures, which indicated that JmjC family genes were conserved after the polyploidization. All G. hirsutumJmjC genes were found to have a typical JmjC domain, and some genes also possess other special domains important for their function. Analysis of promoter regions revealed that cis-acting elements, such as those related to hormone and abiotic stress response, were enriched in G. hirsutum JmjC genes. According to a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis, most G. hirsutumJmjC genes had high abundance expression at developmental stages of fibers, suggesting that they might participate in cotton fiber development. In addition, some G. hirsutumJmjC genes were found to have different degrees of response to cold or osmotic stress, thus indicating their potential role in these types of abiotic stress response. Our results provide useful information for understanding the evolutionary history and biological function of JmjC genes in cotton.

Advances in solid-state white-light-emitting diodes (WLEDs) necessitate the urgent development of highly efficient single-phase phosphors with tunable photoluminescence properties. Herein, the Tm3+, Dy3+, and Sm3+ ions are incorporated into the orthorhombic NaGdTiO4 (NGT) phosphors, resulting in phosphors that fulfill the aforementioned requirement. The emission spectrum of Tm3+ ions overlaps well with the adsorption spectra of both Dy3+ and Sm3+ ions. Under the excitation at 358 nm, the single-phase NaGdTiO4: Tm3+, Dy3+, Sm3+ phosphor exhibits tunable emission peaks in the blue, yellow, and red regions simultaneously, resulting in an intense white-light emission. The coexisting energy transfer behaviors from Tm3+ to Dy3+ and Sm3+ ions and the energy transfer from Dy3+ to Sm3+ ions are demonstrated to be responsible for this phenomenon. The phosphors with multiple energy transfers enable the development of single-phase white-light-emitting phosphors for phosphor-converted WLEDs.

Sucrose transporters (SUTs) play key roles in allocating the translocation of assimilates from source to sink tissues. Although the characteristics and biological roles of SUTs have been intensively investigated in higher plants, this gene family has not been functionally characterized in cotton. In this study, we performed a comprehensive analysis of SUT genes in the tetraploid cotton Gossypium hirsutum. A total of 18 G. hirsutum SUT genes were identified and classified into three groups based on their evolutionary relationships. Up to eight SUT genes in G. hirsutum were placed in the dicot-specific SUT1 group, while four and six SUT genes were, respectively, clustered into SUT4 and SUT2 groups together with members from both dicot and monocot species. The G. hirsutum SUT genes within the same group displayed similar exon/intron characteristics, and homologous genes in G. hirsutum At and Dt subgenomes, G. arboreum, and G. raimondii exhibited one-to-one relationships. Additionally, the duplicated genes in the diploid and polyploid cotton species have evolved through purifying selection, suggesting the strong conservation of SUT loci in these species. Expression analysis in different tissues indicated that SUT genes might play significant roles in cotton fiber elongation. Moreover, analyses of cis-acting regulatory elements in promoter regions and expression profiling under different abiotic stress and exogenous phytohormone treatments implied that SUT genes, especially GhSUT6A/D, might participate in plant responses to diverse abiotic stresses and phytohormones. Our findings provide valuable information for future studies on the evolution and function of SUT genes in cotton.

Cotton is one of the most important economic crops worldwide. As the global demands rising, cotton yield improvement is the most important goal of cotton breeding. Hybrids have great potential for increasing yield, however, the genetic mechanism of hybrids is still not clear. To investigate the genetic basis of cotton hybrids, we resequenced 9053 and sGK9708 with 62.13x coverage depth, the parents of the elite hybrid cotton CCRI63 that has obvious heterosis in lint percentage (LP) and boll weight (BW). Based on the cotton reference genome (TM-1), 1,287,661 single nucleotide polymorphisms (SNPs) and 152,479 insertions/deletions (InDels) were identified in 9053, and 1,482,784 SNPs and 152,985 InDels in sGK9708. Among them, 8649 SNPs and 629 InDels in the gene coding regions showed polymorphism between parents. Moreover, these variations involved 5092 genes, and 3835 of these genes were divided into 10 clusters based on the gene expression profiles. The genes in Cluster 3 and 7 were specifically expressed in the ovule and fiber development stage, suggesting that they might relate to LP and BW. We further co-localized the polymorphic SNPs and InDels with the reported quantitative trait loci (QTLs) of LP and BW, and identified 68 genes containing the polymorphic SNPs or InDels within these QTL intervals and as being related to fiber development. This suggested that the outstanding traits of CCRI63 such as LP and BW might be generated by accumulating the favorable variations from the parents. The results generated herein provide a genetic basis for cotton hybrids and genetic markers for marker-assisted selection breeding of cotton.

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 signfificantly 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.

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 low pH and containing Cl− is also beneficial to accelerate the degradation rate of MB.

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]

Euryale ferox shells were used to prepare activated carbon (AC) by physiochemical activation using potassium hydroxide as the activation agent at 800°C for 2 h. The as-prepared AC surface area was 2028 m2 g-1, while the average pore diameter and total pore volume were 3.425 nm and 0.98 cm3 g-1, respectively. The equilibrium and kinetics for the adsorption of methylene blue (MB) on E. ferox shell-based AC were investigated at 20°C. The equilibrium data for MB adsorption were in agreement with Langmuir equation, and the maximum adsorption value was 617 mg g-1. Adsorption was denoted by two simplified kinetic models, pseudo-first-order and pseudo-second-order equations, respectively. The MB adsorption was well fitted to the pseudo-second-order model. Thermodynamics parameters were calculated and discussed and the adsorption of MB on E. ferox shell-based AC was exothermic and spontaneous. [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]

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]

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]

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]

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]