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3C-SiC nanowires with nanosheets were synthesized via a direct reaction of Si vapor (from solid silicon) and SiO vapor (from silicon and silicon dioxide) with graphene nanosheets at 1500 °C without any additional metal catalyst. The resultant products were characterized by XRD, SEM, TEM and room-temperature photoluminescence (PL) spectroscopy. The results indicated that the product comprised SiC nanowires with nanosheets. The nanowires were mainly composed of curvy aggregated wires with diameters of 30–80 nm, some representative straight whiskers with a pellet at their tips, and some distinctive structures including connected particles, a dumbbell shape with dense stacking faults and periodic twins with screw dislocations. The nanosheets present in the products were thin SiC polycrystalline multilayers within a few nanowires. A combined VLS and VS mechanism was proposed for their formation. The PL spectra of the resultant SiC nanowires with nanosheets indicated a remarkable blue shift in comparison to the bulk SiC, implying their great potential applications in optoelectronic devices.

β-Sialon powder containing nanofibers was synthesized at 1300–1450 °C for 5 h in nitrogen by using transition metals (Fe, Co and Ni) as catalysts. Such synthesis conditions obviously reduced the nitriding temperature (~100 °C) of β-Sialon and increased the degree of nitridation. Observations from the weight gain rates of specimens relative to the content of catalysts suggest that the nitridation process was accelerated sharply via the addition of 0–2.5 wt% metallic catalysts. In addition, the amount of nanofibers of β-Sialon found in the specimens increased with the amount of transition metals, which was governed by the VLS formation mechanism with the help of transition metals. It could be concluded that transition metals not only greatly accelerated the nitridation of Si but also facilitated the formation of β-Sialon nanofibers in the specimens, as the formed metal-containing liquid greatly enhanced the amount of vapor generation.

Improving the adsorption ability of layered double hydroxide (LDH) has been considered as a promising strategy to promote its photodegradation of aqueous pollutants. In this work, nickel-aluminium layered double hydroxides (NiAl-LDH)/biochar nanocomposites were prepared using a simple coprecipitation method, and then applied in synergistic adsorption-photodegradation of tetracycline (TC) in aqueous solutions. In addition, the governing TC removal mechanisms by the nanocomposites were revealed. All NiAl-LDH/BC samples showed strong adsorption and photodegradation of TC. The Langmuir maximum TC adsorption capacity of optimized NiAl-LDH/BC-0.5 reached 124.2 mg/g, which was much better than that of NiAl-LDH (56.1 mg/g) and biochar (11.1 mg/g). Besides, TC photodegradation rate constant of NiAl/BC-0.5 was 3.6 and 4.4 times of that of NiAl-LDH and BC, respectively. The NiAl/BC-0.5 exhibited the maximum TC adsorption-photodegradation efficiency 94.4% in 90 min compared to NiAl-LDH (73.7%) and BC (48.2%). The rate constant of modified Elovich kinetic model for synergistic adsorption and photodegradation on NiAl/BC-0.5 (9.477 min

Synthesis of affordable electrocatalysts with high efficiency at low cost is crucial for large-scale water splitting. Molybdenum carbide (Mo2C) has been suggested to be a promising alternative to noble metal based electrocatalysts for water splitting. In this paper, we fabricated a nanotextured coating of wrinkled Ni-doped Mo2C on carbon fiber paper (CFP) from Ni, Mo and carbon black (CB) via a molten salt method. Such a novel electrocatalyst, denoted as Ni-Mo2CCB/CFP, shows an overpotential of 121.4, 209.3 and 426.4 mV to achieve a current density of 10, 20 and 50 mA cm−2 respectively in acidic medium. The hydrogen evolution reaction (HER) performance of other as-prepared CFP based electrodes (bare CFP, Mo2C/CFP, Mo2CCB/CFP, Ni-Mo2C/CFP and NiCx/CFP) also tested. We found that the addition of carbon black and the doping of Ni could significantly improve the electrocatalytic performance of Mo2C/CFP in terms of overpotential, Tafel slope and exchange current density. This work demonstrates a facile and scalable route using molten salt method for the synthesis of high-performance electrocatalysts from non-precious compounds on carbon materials.

Recently, g-C3N4 has exhibited excellent catalytic performances in photocatalytic water splitting for H2 and O2 generation, degradation of pollutants and CO2 reduction. However, the bulk g-C3N4 demonstrates some disadvantages such as low specific surface area, high defect density, fast recombination possibility of photogenerated electron-hole pairs, and non-recyclable characteristics, leading to low photocatalytic performance and efficiency. The three-dimensional (3D) network-like g-C3N4 composite materials constructed by nanotechnology can effectively improve the adsorption capacity, light response, structure stability and recyclability of photocatalysts, which results in a significant increase in the photocatalytic performance and utilization. It is a novel way to achieve high-efficient separation of photogenerated electron-hole pairs and improve photocatalytic activity. In this review, the recent research progresses especially the synthesis strategy of 3D g-C3N4 composite photocatalysts and their applications for photocatalytic water splitting, degradation of organic pollutants and CO2 reduction are firstly and systematically introduced and discussed. The review and prospect of 3D g-C3N4 composite materials can provide some new ideas and directions for the research and development of 3D g-C3N4 composite photocatalysts with high activity, strong adsorption, facile recyclability, and no secondary pollution.

In order to verify the “Al2O3-template-formation” mechanism of magnesium aluminate (MA) spinel proposed previously using Al2O3 and MgO micro-powders as raw materials, in this work, MA spinel was synthesized by nanograined, plate-like, and fibrous Al2O3 in LiCl molten salt at 1150 °C for 3 h, respectively. The products were characterized by XRD, SEM, TEM, and EDS techniques, and the grain size of the products and raw materials were analyzed. The results showed clearly that the MA spinel was initially nucleated and subsequently developed to octahedral crystal. When the reaction further took place, when using nanograined Al2O3, the newly formed MA spinel seeds initially moved and attached to the surface of the large octahedral MA spinel crystal, and they were subsequently engulfed by the large MA spinel crystal, which further grew via layer-by-layer to become micro-sized crystal. Using plate-like or fibrous Al2O3 raw material, MgO diffused continuously into the interior of Al2O3 to form MA spinel with a gradient growth from surface to depth. These revealed that whatever shape of Al2O3 was used, the synthesis of MA spinel was governed by “Al2O3-template formation mechanism”, i.e., by the reaction of MgO diffusion into the Al2O3 templet in the molten salt.

Due to various advantages, such as rich resources, sodium (Na) is considered an alternative to replace lithium (Li) for carbon nanomaterials. Na has a larger radius, which largely limits the application. With the analysis and discussion, it found that porous carbon with functional groups benefited for energy storage, so functional porous carbon was obtained by spray drying with subsequent annealing and nitric acid etching. Moreover, the surface was modified by functional groups, which can improve wettability and enhance cycling stability. So, as the anodes for sodium-ion batteries (SIBs), the porous C electrode can remain a discharge capacity of 150 mA h g−1 at 1 A g−1 after 1000 cycles. This study opens a pathway to the design of electrodes and hopes that it can apply in other relevant fields.

Novel g-C3N4/h′ZnTiO3-a′TiO2 (CN/h′ZT-a′T) ternary composites were successfully prepared by combining in-situ precursor-synthesized h′ZnTiO3-a′TiO2 (h′ZT-a′T) nanoparticle with nanoporous g-C3N4 (CN) powders. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) results revealed that the grains of hexagonal-phase ZnTiO3 (h′ZT) were in-situ generated together with anatase-phase TiO2 (a′T), forming a symbiotic structure of tightly bonded interface. Compared with CN and h′ZT-a′T, the absorption edge of CN/h′ZT-a′T exhibited a red-shift and the absorption intensity was obviously enhanced. With increasing CN content, the degradation efficiency of CN/h′ZT-a′T for methylene blue (MB) initially increased and then decreased, reaching the highest value of 99.8% with the CN content of 50 wt% (50CN/h′ZT-a′T). The 50CN/h′ZT-a′T composites exhibited the highest apparent reaction rate constant of 2.92 h−1, which was 37.4 and 3.0 times higher than that of h′ZT-a′T and CN, respectively. Photocurrent response of 50CN/h′ZT-a′T was indicative of the highest photocurrent value and the elongated lifetime of photogenerated charges. The greatly enhanced photocatalytic activity was attributed to the high mobility of photogenerated electrons. H′ZnTiO3 with high electron mobility in the direct Z-scheme heterojunction played a role of electronic transfer station and reduced the recombination probability of photogenerated carriers.

Developing an efficient, stable and low-cost noble-metal-free electrocatalyst for the hydrogen evolution reaction (HER) is an effective way to alleviate the energy crisis. Herein, we report a simple and facile approach to synthesize self-supported Ni-doped Mo2C via a molten salt method. By optimizing the content of Ni, the concentration of Ni(NO3)2, and the annealing time, self-supported nanoflower-like electrocatalysts composed of ultrathin nanosheets on carbon fiber paper (CFP) can be achieved. Such a fluffy and porous nanoflower-like structure has a large specific surface area, which can expose many active sites, and promote charge transfer; moreover, all of the above is beneficial for improving the HER performance. Density functional theory (DFT) calculations reveal that the doping of Ni leads to a down shift of the value of the d band center (ed), so that the adsorbed hydrogen (Hads) is easier to desorb from the catalyst surface, thus leading to an enhanced intrinsic catalytic activity of Ni doped Mo2C based catalysts. As a result, Mo2C-3 M Ni(NO3)2/CFP with a nanoflower-like structure prepared at 1000 °C for 6 h exhibits the best electrocatalytic performance for the HER in 0.5 M H2SO4, with a low overpotential of 56 mV (at j = 10 mA cm-2) and a Tafel slope (27.4 mV dec-1) comparable to that of commercial Pt/C (25.8 mV dec-1). The excellent performance surpasses most of the noble-metal-free electrocatalysts. In addition, the outstanding long-term durability of Mo2C-3 M Ni(NO3)2/CFP is demonstrated by showing no obvious fluctuations during 35 h of the HER testing. This work provides a simple and facile strategy for the preparation of nanoelectrocatalysts with high specific surface areas and high catalytic activities, both of which promote an efficient HER.

FCS-like zinc finger family proteins (FLZs), a class of plant-specific scaffold of SnRK1 complex, are involved in the regulation of various aspects of plant growth and stress responses. Most information of FLZ family genes was obtained from the studies in Arabidopsis thaliana, whereas little is known about the potential functions of FLZs in crop plants. In this study, 37 maize FLZ (ZmFLZ) genes were identified to be asymmetrically distributed on 10 chromosomes and can be divided into three subfamilies. Protein interaction and subcellular localization assays demonstrated that eight typical ZmFLZs interacted and partially co-localized with ZmKIN10, the catalytic α-subunit of the SnRK1 complex in maize leaf mesophyll cells. Expression profile analysis revealed that several ZmFLZs were differentially expressed across various tissues and actively responded to diverse abiotic stresses. In addition, ectopic overexpression of ZmFLZ25 in Arabidopsis conferred hypersensitivity to exogenous abscisic acid (ABA) and triggered higher expression of ABA-induced genes, pointing to the positive regulatory role of ZmFLZ25 in plant ABA signaling, a scenario further evidenced by the interactions between ZmFLZ25 and ABA receptors. In summary, these data provide the most comprehensive information on FLZ family genes in maize, and shed light on the biological function of ZmFLZ25 in plant ABA signaling.

Background Dogs are domesticated wolves. Change of living environment, such as diet and veterinary care may affect the gut bacterial flora of dogs. The aim of this study was to assess the gut bacterial diversity and function in dogs compared with captive wolves. We surveyed the gut bacterial diversity of 27 domestic dogs, which were fed commercial dog food, and 31 wolves, which were fed uncooked meat, by 16S rRNA sequencing. In addition, we collected fecal samples from 5 dogs and 5 wolves for shotgun metagenomic sequencing to explore changes in the functions of their gut microbiome. Results Differences in the abundance of core bacterial genera were observed between dogs and wolves. Together with shotgun metagenomics, the gut microbiome of dogs was found to be enriched in bacteria resistant to clinical drugs (P P P P Conclusions Living environment of dogs and domestic wolves has led to increased numbers of bacteria with antibiotic resistance genes, with exposure to antibiotics through direct and indirect methods. In addition, the living environment of dogs has allowed the adaptation of their microbiota to a starch-rich diet. These observations align with a domestic lifestyle for domestic dogs and captive wolves, which might have consequences for public health.

Light is arguably one of the most important environmental factors that determines virtually all aspects of plant growth and development, but the molecular link between light signaling and the autophagy pathway has not been elucidated in plants. In this study, we demonstrate that autophagy is activated during light-to-dark conversion though transcriptional upregulation of autophagy-related genes (ATGs). We showed that depletion of the ELONGATED HYPOCOTYL 5 (HY5), a key component of light signaling, leads to enhanced autophagy activity and resistance to extended darkness and nitrogen starvation treatments, contributing to higher expression of ATGs. HY5 interacts with and recruits HISTONE DEACETYLASE 9 (HDA9) to ATG5 and ATG8e loci to repress their expression by deacetylation of the Lys9 and Lys27 of histone 3. Furthermore, we found that both darkness and nitrogen depletion induce the degradation of HY5 via 26S proteasome and the concomitant disassociation of HDA9 from ATG5 and ATG8e loci, leading to their depression and thereby activated autophagy. Genetic analysis further confirmed that HY5 and HDA9 act synergistically and function upstream of the autophagy pathway. Collectively, our study unveils a previously unknown transcriptional and epigenetic network that regulates autophagy in response to light-to-dark conversion and nitrogen starvation in plants.

Z-scheme heterojunctions are considered as prospective photocatalysts for elimination of organic pollutants. However, the origin of enhanced oxidation ability of Z-scheme heterojunctions is not well understood, and the working mechanism based on internal electrical field is still ambiguous. Here, we report Z-scheme AgIn5S8/ZnO heterojunction with superior photocatalytic activity in degrading pharmaceutical pollutants and enhancing biodegradability of pharmaceutical wastewater. The average oxidation state (AOS) and carbon oxidation state (COS) of pharmaceutical wastewater are significantly increased from 0.42 to 1.35 and 2.94 after photocatalytic treatment of AgIn5S8/ZnO. The analysis on the origin of superior photocatalytic activity reveals that the internal electric field in AgIn5S8/ZnO heterojunction works as a driving force to facilitate efficient separation of photogenerated charge carriers via Z-scheme path, thus generating spatially separated holes and electrons with high redox ability and realizing effective elimination of pharmaceutical pollutants. This study provides deep insight into photocatalytic mechanism of Z-scheme heterojunction for efficacious elimination of organic pollutants and boosted biodegradability of pharmaceutical wastewater.

Single-crystal MoO3 micrometer to millimeter even centimeter belts were prepared via a novel route of oxidizing a discarded molybdenum disilicide heating element at 1000 °C for 3 h. The morphology and structure features, and growth mechanism of the products were evidently investigated by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicated that the powdery and fibrous products were typical α-MoO3 belt-like structures which size could develop from micrometer to several millimeter even centimeter in length and up to 0.5 mm in width. It should be formed preferentially along the [001] direction via layer by layer growth to form 1-D single MoO3 belts by vapor-solid mechanism. Thermal and luminescence properties of the products were revealed by thermogravimetric analysis and differential thermal analysis and photoluminescence spectra that the resultant α-MoO3 belts had good thermal stability and characteristics of luminescence with a central peak at 481 nm. The MoO3 belts are of good potential being applied to luminescent and high temperature devices.

Ca-α-Sialon powders was initially synthesized by carbothermal reduction-nitridation (CRN) of SiO2, AlN, CaF2 and carbon black at 1700 °C, subsequently was used as the raw material to prepare Ca-α-Sialon ceramic by hot-pressed (HP) sintering at 1900 °C. The main intermediate nitridated products were Si2N2O and O-Sialon formed at 1400 °C–1600 °C. The resultant Ca-α-Sialon just had hexagonally short prismatic structure at 1700 °C. In order to obtain its elongated crystals, α-Sialon seeding was introduced during CRN process. The results revealed that the seeding facilitated crystal refinement of Ca-α-Sialon and the increase in its aspect ratios from 2 to 5.45. The resultant HP-sintered Ca-α-Sialon ceramic with seeding at 1900 °C had compact structure with fine and elongated grains, forming a highly interlocked microstructure. They had a Vickers indentation hardness of ∼21 GPa independent of the microstructure. The flexural strength and fracture toughness of the Ca-α-Sialon ceramics drastically increased with increasing the amounts of seeds, which was in accordance with that in grains aspect ratio of α-Sialon crystals synthesized by CRN as function of amounts of seeds. The improved flexural strength and fracture toughness should be ascribed to the development of elongated α-Sialon grains, which could enhance crack deflection and grain pullout.

Nanohybrids of graphene-decorated carbon-coated LiFePO4 nanospheres are prepared using a ball milling-assisted rheological phase method combined with a solid-state reaction. The hybrids are characterized by XRD, SEM, TEM, HRTEM, XPS, Raman and TGA, and their electrochemical properties are studied by CV, EIS and galvanostatic charge-discharge. The experimental results exhibit that multilayer graphene films are decorating carbon-coated LiFePO4 nanospheres without stacking, which results in an abundance of mesopores constituting a unique 3D “sheets-in-pellets” and “pellets-on-sheets” conducting network structure. This structure highlights the improvements of the rate and cyclic performance as a cathode material for lithium-ion batteries, because the highly conductive and plentiful mesopores promote electronic and ionic transport. As a result, the hybrids with approximately 3 wt% graphene exhibit an outstanding rate capability with an initial discharge capacity of 163.8 and 147.1 mA h g−1 at 0.1 C and 1 C, and the capacity is retained at 81.2 mA h g−1 even at 20 C. Moreover, the composites also reveal an excellent cycling stability with only an 8% capacity decay at 10 C after 500 cycles.

The development of cheap, efficient and high activity non-noble-metal oxygen evolution reaction (OER) electrocatalysts is of great interest in promoting the application of water splitting. Herein, the flower-like phosphates were grown in situ on a porous microwave sintered CoCrFeNiMo high entropy alloy (HEA) by the hydrothermal–phosphorization method. The metal phosphates can promote the formation of hydroxides with high catalytic activity on the surface of the catalyst. The obtained porous HEA phosphates exhibit a low overpotential of 220 mV at 10 mA cm−2, a small Tafel slope of 30.3 mV dec−1 and superior stability in 1.0 M KOH. Especially, after continuous cyclic voltammetry (CV) 5000 cycles, the catalyst only requires the overpotential of 210 mV at 10 mA cm−2. The enhanced OER performance of this porous HEA is be attributed to 3D internal connected nanoporous structure, high conductivity, abundant metal (oxy)hydroxide nanosheets and the presence of phosphonates, that provides a sufficiently large surface exposure and allows the acceleration of the electron transfer rate between various species.

Graphitic carbon nitride (g-C 3 N 4 ) prepared by traditional methods has various disadvantages, e.g., small specific surface area, low band gap, high photo-generated carriers recombination and low exfoliation efficiency, which limits its practical application. In this study, folded nano-porous graphene-like g-C 3 N 4 (abbreviated as FNPGLCN) was prepared by a simple but quite effective method of calcining urea in water. The effects of calcination temperature on crystal structure, energy band and microstructure of g-C 3 N 4 were investigated. The photocatalytic activity for methylene blue (MB) degradation under visible-light was evaluated. The results revealed that the FNPGLCN had higher specific surface area (197 m 2 /g) and larger band gap (2.87 eV) than bulk g-C 3 N 4 . With calcination temperature rising from 450 to 500 °C, the pore size and specific surface area of FNPGLCN increased. However, the pore structure almost disappeared and the thickness of g-C 3 N 4 became thinner at 550 °C. Compared with bulk g-C 3 N 4 , the photocatalytic degradation rate of FNPGLCN for MB increased from 0.131 to 1.298 h −1 . The significant enhancement of visible photocatalytic activity was mainly attributed to folded nano-porous structure, which simultaneously improved visible-light absorption range and strength, and enlarged the band gap and specific surface area of g-C 3 N 4 .

Electrochemical water splitting is considered to be one of the most potential strategies to achieve the hydrogen economy. In this paper, the porous NiMo alloys used as efficient electrocatalysts were designed and synthesized by microwave sintering powder metallurgy method. The as-prepared porous NiMo alloys as good electrocatalysts exhibit excellent hydrogen evolution reaction (HER) performance and outstanding durability in alkaline electrolyte (1.0 M KOH). Especially, the porous Ni6Mo4 alloy shows smaller overpotential of 37 mV at current density of 10 mA cm−2 and a low Tafel slope of 82.1 mV dec−1. The efficient electrocatalytic performance of Ni6Mo4 alloy can be attributed to the synergies of Ni, Mo and NiMo intermetallic compound, more active sites and quicker charge transfer rate.

The application of a porous silica (PS) transition layer in an inorganic-organic aeronautic laminated glass can effectively solve the material failure caused by the performance difference of the inorganic-organic materials. The effect of porous silica transition layer thickness on the mechanical and optical properties of laminated glass was investigated. The microstructure of the porous silica transition layer was analyzed by scanning electron microscopy. The film thickness was verified using a step profiler. The failure strength of laminated glass with the porous silica transition layer was tested by a universal testing machine. Finite element modeling of laminated glass with the porous silica transition layer was performed by ANSYS software. Tensile stress between the porous silica and the polyurethane was simulated for different porous silica film thicknesses. Experimental and theoretical results indicated that with the increasing the thickness of the transition film, the failure stress of the laminated glass increased. Improvements in the mechanical properties of the laminated glass are saturation at a PS thickness of approximately 3.8 μm. Keywords: Aeronautic laminated glass, Porous silica transition layer, Mechanical properties, Simulation

Ni metal was directly used as raw materials to prepare Ni-gadolinia doped ceria (GDC) anode. In order to overcome the problems of agglomeration and oxidation of Ni particles in sintering, modified heterogeneous precipitation method and fast sintering technique were employed to prepare GDC coated Ni powders and Ni-GDC cermets. XRD, TG-DTA, SEM and AC impedance spectra measurements were applied to examining phase composition, oxidation, microstructure, and electrical property of GDC coated Ni powders and Ni-GDC composites. The results showed that GDC coated Ni powders were successfully synthesized by modified heterogeneous precipitation at pH = 7.7. Overhigh pH value resulted in the homogeneous precipitation (self-nucleation) of GDC that uncoated on Ni core. After coating, the oxidation temperature of sample was increased by 200 °C and the oxidation weight gain was decreased from 26.3% to 12.5% at 800 °C. With fast sintering at 1200 °C, Ni-GDC cermets sintered with 40 °C/min exhibited finer grains, lower impedance and larger hardness than that sintered with 10 °C/min and 80 °C/min.

γ-aluminium oxynitride (AlON) has an excellent thermal and chemical stability, which makes AlON an attractive candidate for a wide range of applications. Production of transparent AlON is extremely challenging because residual porosity must be reduced to an absolute minimum. This can be achieved by spark plasma sintering (SPS) and introducing sintering additives. This article provides a review of research activities that concentrate on the development of spark plasma reaction sintering of AlON ceramics with and without sintering additives. Influence of the most important operating parameters (atmosphere, temperature, processing time, heating rate, etc) on product characteristics and process dynamics is reviewed for AlON ceramics. Comparison of SPS over conventional methods including pressureless sintering, hot pressing sintering and others is demonstrated. Recent advances and challenges in the synthesis of AlON ceramics by SPS are also discussed.

Designing heterojunction photocatalysts with strong interfacial interaction and matched band structure is an effective way to reduce the recombination of photogenerated carriers. Herein, the exfoliated black phosphorus (BP) nanosheets were coupled with BiOBr nanosheets having higher Fermi level, and thereby it constructed a novel layered BP/BiOBr nano-heterojunction with chemically bonding, larger contact interface and unique band structures. BiOBr nanosheets were self-assembled on the surface of BP nanosheets by a facile liquid-phase ultrasound combined with solvothermal method. The photocatalytic performance for tetracycline (TC) degradation, oxygen evolution and H2O2 production rate of Sol-10BP/BiOBr was 7.8, 7.0 and 2.6 times than that of pure BiOBr, respectively. The in-situ generated H2O2 and OH became the main active species of mineralization and decomposition of TC. The novel S-scheme two-dimensional BP/BiOBr nano-heterojunction for boosting spatial charge separation retained the useful holes-electrons with higher redox ability, which was very beneficial for producing more OH, H2O2 and O2, and the photocatalytic activity was greatly improved.

Single phase β-Si3N4 with microcrystals was synthesized via carbothermal reduction-nitridation (CRN) of quartz and carbon coke powder as starting materials. The effects of reaction parameters, i.e., heating temperature, holding time, C/SiO2 ratio, Fe2O3 additive and β-Si3N4 seeds on the phase transformation and morphology of products were investigated and discussed. Rather than receiving a mixture of both α- and β- phases of Si3N4 in the products, we synthesized powders of β-Si3N4 single polymorph in this work. The mechanism for the CRN synthesis of β-Si3N4 from quartz and the formation mechanism of Fe3Si droplets were discussed. We also firstly reported the formation of Fe3Si Archimedean solids from a CRN process where Fe2O3 was introduced as additive. Comparing to the gear-like short columnar morphology observed in samples without β-Si3N4 seeding, the addition of β-Si3N4 seeds led to an elongated morphology of final products and much finer widths. In addition, the β-Si3N4 microcrystals exhibited a violet‒blue spectral emission range, which could be highly valuable for their future potential optoelectronic applications.

Carbon source precursors for high-grade, clean, and low-carbon refractories were obtained by in situ exfoliation of flake graphite (FG) and phenol&ndash, formaldehyde resin (PF) composites with three-roll milling (TRM) for the fabrication of graphite nanoplatelets. In addition, by using Ni(NO3)2&middot, 6H2O as a catalyst in the pyrolysis process, multidimensional carbon nanostructures were obtained with coexisting graphite nanoplatelets (GNPs), glassy carbon (GC), and carbon nanotubes (CNTs). The resulting GNPs (exfoliated 16 times) had sizes of 10&ndash, 30 &mu, m, thicknesses of 30&ndash, 50 nm, and could be uniformly dispersed in GC from the PF pyrolysis. Moreover, Ni(NO3)2&middot, 6H2O played a key role in the formation and growth of CNTs from a catalytic pyrolysis of partial PF with the V&ndash, S/tip growth mechanisms. The resulting multidimensional carbon nanostructures with GNPs/GC/CNTs are attributed to the shear force of the TRM process, pyrolysis, and catalytic action of nitrates. This method reduced the production costs of carbon source precursors for low-carbon refractories, and the precursors exhibited excellent performances when fabricated on large scales.

While lithium-ion batteries (LIBs) have been widely used in commercial devices, finding suitable anode materials for alkali metal batteries is still challenging. Therefore, Ni3S2/Ni@N-doped carbon composite electrode was fabricated as the anode for alkali metal batteries. It was found that the Ni3S2/Ni@N-doped carbon electrode achieved a capacity of 742 mAh g−1 at the 1500th cycle at the current density of 1000 mA g−1 for LIBs, and obtained 275 mAh g−1 at the 250th cycle during 500 mA g−1 for Na+ storage. Moreover, it showed 52 mAh g−1 after 50 cycles at 100 mA g−1 for K+ storage. The excellent performances of this electrode is likely due to the combined effect of Ni and C layer. This work provides a simple approach approach for the design of high-performance materials that can be applied to commercial production as a potential substitute for the current alkali ion battery anodes.

Rational design of the photocatalysis is of vital importance to mediate many important photocatalytic reactions such as water splitting, pollutant degradation and CO2 reduction. In this work, we employed a solvent evaporation induced self-assembly method to prepare a novel S-scheme heterojunction composite by combining sulfur-doped porous graphite carbon nitride (S-pCN) with tungsten oxide (WO2.72) semiconductors which manifest effective interface contact and excellent photocatalytic performance. During the formation of the heterojunction, the electron defect state of surface oxygen vacancies on WO2.72 can be filled by the lone pair electrons of sulfur and nitrogen elements on S-pCN. Through the adjustment of composite ratios, appropriate surface oxygen vacancies were retained on WO2.72, thereby fascinate the migration of electrons and the generation of free radicals. The internal electric field (IEF) and the band bending effects accelerate the transfer of photogenerated charges at the interface, thereby promotes the recombination of useless photogenerated carriers, retains photogenerated electron (e−) and hole (h+) with the higher redox potentials, improves the separation and utilization efficiency of the photogenerated carriers and enhances the photocatalytic activity of the system. This work provides new insights for the design of a novel S-scheme heterojunction photocatalyst for highly efficient simultaneous photocatalytic degradation and hydrogen evolution activity.

Promoting in-situ growth on the Ni foam to form an integrated electrode could prove useful for improving the area-specific capacity and adhesion between the collector and active material. Here, a NiO/NiS2 nanosheet integrated electrode was designed and obtained by a hydrothermal method. The integrated electrode consisted of a mixture of NiS2 and NiO and was in the form of a nanosheet. The electrode showed high area-specific capacities as the anode for alkaline ion batteries and could achieve 1.51 (150th cycle), 0.93 (100th cycle), and 0.11 mAh•cm−2 (30th cycle) for Li+/Na+/K+ storage.

Due to the high price of noble metal catalysts, there is an urgent demand for the development of inexpensive and earth-abundant electrocatalysts for the oxygen evolution reaction (OER). It is known that a hierarchical structure can effectively increase the catalytic area and improve the charge transfer of the OER electrocatalyst, while Ni foam is known to be an advantageous substrate. Therefore, in this work a hierarchical Mn–CoO@Fe(OH)3 nanofiber array was prepared by the hydrothermal reaction and immersion at room temperature, and X-ray diffraction and transmission electron microscopy measurements were carried out to characterize the microstructure of the nanofiber array. X-ray photoelectron spectroscopy was used to analyze the valence states of the array, demonstrating the successful synthesis of the Mn–CoO@Fe(OH)3 nanofiber. As the catalyst for OER, the Mn–CoO@Fe(OH)3 nanofiber array showed a low overpotential of 195 mV at a current density of 10 mA cm−2 as well as high stability (80 h) in the durability test. This work demonstrates the feasibility of the design of hierarchical nanostructure electrodes with high electrochemical performance for catalytic reactions and various battery applications.

One-dimensional SiO2@SiC shell–core nanowire was fabricated on a SiC substrate without any catalyst using a laser sintering method. Based on a solid–liquid–vapor–solid (SLVS) in situ growth mechanism, the as-synthesized SiO2@SiC nanowires of about 60 nm diameter with a shell thickness of about 13 nm were grown. Varying the power density of laser sintering allowed the final SiC particle morphology to be controlled from grainy to whisker-like. High power density or high temperature benefited the nucleation probability of SiC whiskers. The isothermal oxidation test showed that the SiO2@SiC nanowires have good thermodynamic stability at high temperature. The photoluminescence (PL) property of SiO2@SiC nanowire was also investigated. The observed emission peaks were composed of an UV peak centered at 365 nm (3.40 eV) and a blue peak centered at 453 nm (2.74 eV). The theory behind the PL property and the growth mechanism of the SiO2@SiC nanowire were also discussed.

Aluminum oxynitride (AlON) ceramic was fabricated by in-situ hot pressing sintering (HPS) from Al 2 O 3 and AlN doped with Y 2 O 3 and La 2 O 3 as well as without dopant for comparison. Dense AlON ceramic with a relative density of 99.7% was obtained by HPS doped with 0.4 wt% Y 2 O 3 and 0.1 wt% La 2 O 3 at 1700 °C for 4 h. The maximum fracture toughness of AlON ceramic with and without dopant was 3.74 MPa m 1/2 and 2.27 MPa m 1/2 , respectively. The maximum Vickers hardness of AlON ceramic with and without dopant was 18.3 GPa and 16.5 GPa, respectively. Compared with those of undoped AlON ceramic, the relative density and the fracture toughness of Y 2 O 3 -La 2 O 3 co-doped AlON ceramic were obviously improved. Overlarge grain size would reduce the Vickers hardness of AlON. The sintering activation energy of Y 2 O 3 -La 2 O 3 co-doped AlON was about 57% of that of undoped AlON. The sintering activity of AlON was highly improved by co-doping with Y 2 O 3 and La 2 O 3 .

The prevalence of entrepreneurship not only varies across regions, but also differs among industries. Based on a unique data set of 146 manufacturing industries across 30 provincial-level regions in China, this study investigates the importance of geographical conditions and industry dynamism on net entry rates of Chinese manufacturing firms, and empirically explores how these two sets of factors jointly influence the distributional pattern of entrepreneurship. By testing for the significance of interactions between industry dynamism and local condition variables, it is found that growth-driven entrepreneurial activities favor agglomerated regions and do not value knowledge creation capability much, although both knowledge creation capability and factor market maturity are important for a region to attract entrepreneurs pursuing technological opportunities. For start-ups exploiting niche opportunities, agglomeration and local competition both act as deterring factors. Overall, the results confirm the importance of local conditions and industry structural variables as joint determinants of entrepreneurship in Chinese manufacturing industries.

In this work, the effect of MgO addition on the sinterability and crystallization of sintered glass–ceramics prepared from powder mixtures of waste glass and fly ash was investigated. The bulk density of the glass–ceramics decreased with increasing the MgO content, reaching the maximum value at the sintering temperature of 1000 °C. The amounts of the glass-ceramic crystalline phases, i.e., pyroxene and forsterite, increased with the MgO content. Furthermore, when the MgO content increased from 5 to 25 wt%, the crystallization mechanism changed from bulk to surface crystallization. The flexural strength was significantly influenced by three factors, i.e., porosity, crystallinity, and crystal shape anisotropy, and reached the maximum value of 78 MPa for a 10 wt% content of MgO. Fast sintering promoted the densification process, thus increasing the glass-ceramic flexural strength. As a result, owing to their high strength and relatively low density, these sintered glass–ceramics appear promising for potential applications in lightweight construction tiles.

The spatial charge separation and explosion of high-active facets were considered as a pair entwined tactics for photocatalyst material with high ability. Herein, Ag3PO4/BiVO4 was controllably fabricated by selectively deposited Ag3PO4 on the high-active (0 4 0) facets of BiVO4. The photocatalytic activities of Ag3PO4/BiVO4 in degradation TCH was approximately 8.8 and 5.7 times than that of BiVO4 and Ag3PO4, accordingly. Furthermore, the mineralization rate of TCH over Ag/Bi4 (0 4 0) could reach to 91% after irradiated 180 min. After systematic characterization, the built-in electric field in Ag3PO4/BiVO4 was produced by the interfacial interaction between Ag3PO4 and BiVO4, which served as a charge carrier space that facilitated the transfer and separation of photogenerated carriers. Therefore, the spatial charge separation, explosion of high-active facets of BiVO4 and interfacial effects between Ag3PO4 and BiVO4 were in favor of high catalytic activity.

Reduced graphene oxide modified black phosphorus quantum dots (rGO@BPQDs) were obtained through surface modification of BPQDs with rGO via an ultrasound-assisted liquid phase method. The rGO@BPQDs could effectively enhance the chemical and structural stability of BPQDs. Zero-dimension rGO@BPQDs were firmly anchored on mesoporous g-C3N4 (CN) via a self-trapping pore confinement effect and π-π interactions to form CN/rGO@BPQDs, which remarkably improved the photoelectric properties of CN. The responsive wavelength of CN/rGO@BPQDs could be extended to 800 nm. The kinetic constant of Rhodamine B and tetracycline degradation reached 0.183 and 0.0194 min−1, respectively. The H2O2 production rate of CN/rGO@BPQDs was 2.6 times that of porous CN. The improved photocatalytic performance and remarkable increase in free radicals are attributed to the formation of n-n type high-low junctions as well as the internal electric field based on different Fermi levels between CN and BPQDs. These collectively promote spatial separation of photogenerated carriers.

Prior research has examined how financial constraints and agency costs affect the allocation of investment in research and development (R&D). However, we still know little about the effect of both factors simultaneously. It is important to investigate this to determine whether the pull or push effect dominates in R&D investment allocation and to determine the causes and extent of R&D investment inefficiency further. While the pull effect reduces investment, the push effect encourages firms to invest more in R&D. The two-tier frontier model was used to examine data from Chinese listed firms from 2009 to 2014. The results indicate that agency costs (the push effect) are the predominant cause of R&D investment inefficiency. The push effect causes 87.97% of Chinese firms to overinvest and leads to an average overinvestment of 41.33% above the optimal level. Moreover, this R&D investment inefficiency is heterogeneous in terms of state ownership structures. A higher percentage of state-owned firms suffer from severe overinvestment. We also found that agency costs result from the principal-principal (PP) and not principal-agent (PA) conflicts in China.

Single-crystal MoO3 micrometer to millimeter even centimeter belts were prepared via a novel route of oxidizing a discarded molybdenum disilicide heating element at 1000 °C for 3 h. The morphology and structure features, and growth mechanism of the products were evidently investigated by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicated that the powdery and fibrous products were typical α-MoO3 belt-like structures which size could develop from micrometer to several millimeter even centimeter in length and up to 0.5 mm in width. It should be formed preferentially along the [001] direction via layer by layer growth to form 1-D single MoO3 belts by vapor-solid mechanism. Thermal and luminescence properties of the products were revealed by thermogravimetric analysis and differential thermal analysis and photoluminescence spectra that the resultant α-MoO3 belts had good thermal stability and characteristics of luminescence with a central peak at 481 nm. The MoO3 belts are of good potential being applied to luminescent and high temperature devices.