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Z-pinning is an effective method to improve the delamination resistance of composite laminates. The microstructure and manufacturing parameters have a great influence on the properties of z-pin composite laminates. In order to explore the influence of microscopic characteristic parameters on material properties and damage analysis, a parameterized RVE finite element model algorithm for automatic establishment of z-pin reinforced composites was proposed. The algorithm involves avoiding in-plane fibers to pin, generating fiber waviness, and assembling pin-fiber–matrix. Moreover, the statistical distribution of fiber misalignment angle can also be controlled. The developed program can generate RVE models with different parameters efficiently and quickly, such as fiber volume fraction, pin volume fraction, pin diameter, RVE size and fiber waviness. The statistical verification of the distribution of fiber misalignment angle can satisfy the probability distribution modeling of fiber angle. The generated model is divided into meshes, and finite element calculation can be realized. This work is of great significance to study the effects of microscopic characteristics on the properties and to optimize the design of z-pin reinforced composites. [ABSTRACT FROM AUTHOR]

Abstract: The chemical composition of shaddock (Citrus paradisi) mainly consisted of polyphenols, proteins and polysaccharides. However, polysaccharides from shaddock materials have received much less consideration than polyphenols. Herein, a water-soluble neutral polysaccharide from the endodermis of shaddock was isolated and showed good bioactivities. Crude polysaccharides from the endodermis of shaddock (EPS) was extracted with hot water and separated on a DEAE Sepharose FF gel filtration column to obtain NEPS. The IR and UV spectra of NEPS showed that NEPS was mainly composed of polysaccharide and there are no proteins existing in NEPS. The DPPH radical scavenging and reducing power of NEPS are much lower than those of crude EPS; however, Citrus flavonoids significantly improved the DPPH radical scavenging potential and reducing power of NEPS. The crude EPS (5mg/mL) showed a similar inhibitory effect (77.92±5.03%) with NEPS (5mg/mL) (74.63±4.71%) on α-amylase. [Copyright &y& Elsevier]

Abstract: Monoclinic BiVO4 nanorods and nanoplates were synthesized via the CTAB/water/n-butanol/n-octane microemulsion-mediated hydrothermal process. The physical and photophysical properties of the as-prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, and UV–vis diffuse reflectance spectroscopy (UV–vis). It was found that the ratio of H2O to CTAB in microemulsion played a key role in the morphology evolution of the products. The possible formation mechanism of BiVO4 nanostructure with various morphologies was briefly discussed. The Raman results indicated that the symmetry distortions in the local structure of the synthesized BiVO4 were affected by the morphology of the products. The bandgaps (E g) of BiVO4 nanorods and nanoplates are 2.45 and 2.38eV, respectively. The synthesized BiVO4 nanoplates showed superior photocatalytic activity compared with BiVO4 nanorods due to their higher degree of structural distortion, larger surface area, and thinness. [Copyright &y& Elsevier]

Abstract: Novel Fe doped mesoporous TiO2 microspheres were fabricated by an ultrasonic–hydrothermal method when tetrabutyl titanate was used as a precursor and octadecylamine was used as a structure-directing agent. The mesoporous materials were characterized by XRD, SEM, TEM, N2 adsorption–desorption measurements, XPS, FL, and UV–vis. The results suggest that both ultrasonic treatment and hydrothermal procedure are critical for the fabrication of Fe doped mesoporous TiO2 microspheres with a combination of regular morphology, large specific surface area, high crystallinity, and high thermal stability. Low-angle XRD and TEM images indicate that the disordered wormhole-like mesostructure of Fe doped TiO2 microspheres with diameters of about 300−400nm is actually formed by the agglomerization of nanoparticles with an average size of about 10nm. The photocatalytic activity of Fe doped mesoporous TiO2 microspheres was evaluated by the photodegradation of methyl orange. A small amount of Fe3+ can obviously enhance their photocatalytic activity. The optimal atomic ratio of Fe to Ti for photocatalytic activity is about 0.5at%. [Copyright &y& Elsevier]

Abstract: Novel fishbone-like LaVO4:Eu3+ nanostructure has been successfully fabricated via a facile and surfactant-free hydrothermal route at 160°C. The obtained samples were characterized using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution field-emission transmission electron microscope (HRTEM), Brunauer–Emmett–Teller (BET) method, Infrared spectroscopy (IR), UV–vis diffuse reflectance spectroscopy (UV–vis) and photoluminescence spectroscopy (PL). The TEM and XRD results showed that numerous secondary branches vertically grew from the main stem and formed tetragonal LaVO4 nanostructure with a fishbone-like morphology. Further studies revealed that the pH value of hydrothermal solution played a crucial role in the morphology evolution of LaVO4 nanocrystals. The room temperature photoluminescence spectrum of fishbone-like LaVO4:Eu3+ nanocrystal exhibited a stronger red emission at about 617nm than the samples with other shapes. A possible growth mechanism of fishbone-like LaVO4:Eu3+ was also briefly discussed. [Copyright &y& Elsevier]

Abstract: Monoclinic bismuth vanadate (BiVO4) samples with regular morphologies were prepared by a facile hydrothermal process with Bi2O3 and NH4VO3 as starting materials. The physical and photophysical properties of the as-prepared samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), infrared spectroscopy (IR), and UV–vis diffuse reflectance spectroscopy (UV–vis). It was found that cuboid-like, square plate-like and flower-like BiVO4 could be readily obtained by tailoring the pH values of the reaction suspensions in the presence of CTAB. Both pH value and CTAB played crucial roles in the morphology evolution of the as-prepared samples. The bandgaps (E g) of cuboid-like, square plate-like and flower-like BiVO4 were 2.39eV, 2.40eV and 2.46eV, respectively. The photocatalytic performance of the as-prepared BiVO4 was much better than that of P25 for photodegradation of methyl orange under sunlight irradiation. The photocatalytic activities of BiVO4 samples were highly related to their crystallinities and shapes. [Copyright &y& Elsevier]

Abstract: GaOOH:Eu3+ nanorods with different aspect ratios were prepared by hydrothermal method at 140°C. α- and β-Ga2O3:Eu3+ were converted from as-prepared GaOOH:Eu3+ particles by calcination at 500 and 850°C, respectively. The products were characterized with X-ray diffraction (XRD), transmission electron microscope (TEM) and photoluminescence (PL). Results show that solution pH values play a key role in the formation of the GaOOH:Eu3+ powders with different morphologies and α- and β-Ga2:Eu3+ inherit the morphology of GaOOH:Eu3+ exactly. The photoluminescence characteristics of β-Ga2O3:Eu3+ were also investigated. Experimental results reveal that the color purity of β-Ga2O3:Eu3+ nanorods with high aspect ratio is enhanced in comparison with β-Ga2O3:Eu3+ nanorods with low aspect ratio. [Copyright &y& Elsevier]

Abstract: Dy3+-doped YVO4 nanorods were synthesized via a low temperature hydrothermal route in n-propyl alcohol–water mixtures at 150°C. The structures and optical properties of products were investigated using the X-ray powder diffraction, transmission electron microscopy, and photoluminescence spectroscopy. The results showed that these nanorods might be fabricated through dissolving of small particles and the depositing of components on large particles. The photoluminescence (PL) measurements showed that these nanorods exhibited improved chromaticity compared with YVO4:Dy3+ irregular nanoparticles. It can be ascribed to the perfect crystal structure of nanorods. From PL spectra, it is found that YVO4:Dy3+ nanorods annealed at higher temperature have higher ratio of yellow (4F9/2 → 6H13/2) to blue (4F9/2 → 6H15/2) emissions, which ascribe to high site symmetry resulting from the crystallite size and crystallization increased. [Copyright &y& Elsevier]

A series of ternary-composite were synthesized by the integration of 7% silver-mixed ZnO NPs with different contents (3.5–75 wt%) of sulfur-doped graphitic carbon nitride (S-g-C 3 N 4). A unique ternary-composite formed between Ag/ZnO and S-g-C 3 N 4 generates a vast number of catalytic active sites for photocatalytic degradation. The as-synthesized 7% Ag/ZnO nanocomposite showed maximum methylene blue (MB) degradation rate among the series (0–9%) under visible light. The synergistic effects of the Ag/ZnO/S-g-C 3 N 4 ternary-composite enhanced photocatalytic activity, and photo-corrosion resistance was demonstrated successfully. The photo-corrosion of ZnO NPs was inhibited by simultaneous mixing Ag and coupling with S-g-C 3 N 4 , which was verified through cyclic photo-degradation with six consecutive dye degradation tests. Interestingly, the 25% Ag/ZnO/S-g-C 3 N 4 ternary-composite exhibited a significant increase in photodegradation of MB. ga1 • A series of ternary composite Ag/ZnO nanocomposite with S-g-C 3 N 4 were synthesized having a high photocatalytic ability. • 7% Ag/ZnO nanocomposite showed maximum dye degradation rate among the series. • The photocatalytic activity of 25% Ag/ZnO/S-g-C 3 N 4 is significantly increased by the integration of Ag/ZnO with S-g-C 3 N 4. [ABSTRACT FROM AUTHOR]

The development of advanced catalyst cathode with high oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities, low cost and rich natural resource is a key to improve the electrochemical performance of rechargeable lithium oxygen batteries (LOBs). Heteroatoms-doped carbon nanomaterials as cathodes for LOBs with improved electrochemical performance have attracted great attentions. Herein, we report an approach to synthesize holey graphene and a boron doped holey graphene (B-hG) with plenty of holey structure and high B doping level of 6 at. %. Benefiting from plenty of holey structures and B related active sites to accelerate the ORR and OER kinetics, the B-hGs (e.g. , B-hG-700) cathode displays an extremely high capacity of 19698 mA h g−1 at 100 mA g−1 and long cycling stability over 120 cycles. Both experimental results and density functional theory calculations indicate that the discharge products (e.g. , Li 2 O 2) prefer to nucleate and vertically grow near holes/edges sites, which facilitates the formation of relatively isolated and uniformly distributed Li 2 O 2. Such formation process significantly reduces the agglomeration of Li 2 O 2 and effectively provides many spaces to accommodate Li 2 O 2 , thus leading to the enhanced ORR and OER kinetic. [Display omitted] • The hG was produced by annealing GO with the Mn species ,followed by an acid washing process. • 6.7at.% B was successfully doped to hG to form B-hG-700. • The B-hG-700 as cathode for LOB displays outstanding lithium storage properties. [ABSTRACT FROM AUTHOR]

Abstract: Copper ions surface-doped titanium dioxide nanotubes were prepared via an assembly process based on the reactions between Cu(NH2CH2CH2NH2)2(OH)2 and hydroxide radicals on the surface of TiO2 nanotubes, followed by the heat treatment in air at 723K. The as-prepared samples were characterized with infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and fluorescence spectroscopy (FL). The photocatalytic activity of the copper ions surface-doped titanium dioxide nanotubes was investigated by photodegradation of Rhodamine B. The results showed that copper ions were successfully introduced onto the surface of TiO2 nanotubes. And two kinds of copper species of Cu(I) and Cu(II) were found on TiO2 surface. Copper ions act as electron trappers facilitating the separation of electrons and holes on the surface of TiO2 nanotubes, which allows more efficiency for the photodegradation of Rhodamine B. [Copyright &y& Elsevier]

It is still a challenge to explore self-healable and reprocessable polysiloxane elastomer with improved mechanical strength and superior transparency. In this work, a self-healable and reprocessable polysiloxane elastomer with fine mechanical strength and optical transparency is facilely constructed by thiol-ene photopolymerization between thiol-functionalized silicone resin (MDT-SH) and vinyl-terminated polysiloxane and diboronic ester. The UV radiation intensity, molecular structure of MDT-SH and thiol/ene molar ratio play an important role in the thiol-ene photopolymerization and mechanical properties of polysiloxane elastomer. The damaged elastomer is completely repaired at 80 °C after 3 h, and the waste elastomer can be reprocessed into new items with 90% recovery of mechanical property. More importantly, its transmittance at 400–800 nm is higher than 95%, and it is almost unaffected by the healing process. This self-healable, transparent and tough polysiloxane elastomer has the potential to develop flexible electronics and wearable devices. [Display omitted] • A novel thiol-functionalized phenyl silicone resin prepared by hydrolysis-condensation reaction • A transparent silicone elastomer constructed by facile thiol-ene photopolymerization • This elastomer is repeatedly self-healable and reprocessable by dynamic boronic ester cross-linkages. • The silicone elastomer has outstanding mechanical strength and optical transparence. [ABSTRACT FROM AUTHOR]

Abstract: Titanium dioxide nanoparticles were prepared via a facile hydrothermal approach with titanium tetrabutoxide as a precursor under strongly acidic condition. The transmission electron microscopy results showed that novel flower-like, leaf-like, and rod-like TiO2 nanoscale materials could be easily obtained by tailoring the concentration of the precursor and the reaction temperature. And the analysis from X-ray diffraction revealed that all the as-prepared products under different experimental conditions possessed a mixed crystal phase of anatase and rutile. The reasons for the phase formation were discussed. Larger proportion of rutile phase should be ascribed to the strongly acidic conditions. The growth mechanisms of TiO2 nanostructures with various morphologies were also proposed. [Copyright &y& Elsevier]

In order to overcome severe capacity fading of LiCoO 2 /graphite lithium-ion battery at a high voltage, lithium difluoro(oxalate)borate (LiDFOB) was investigated as an electrolyte additive. Electrochemical tests demonstrate that by adding 1 wt.% LiDFOB into a carbonate electrolyte, the capacity retention of the battery after 300 cycles at 1 C between 3.0 and 4.5 V is improved from 42.1 to 80.2%. With the help of computational calculations and physical characterization techniques, we found that the LiDFOB strongly coordinates with Co ions, which inhibits the dissolution of cobalt from bulk LiCoO 2 and prevents Co deposition on the anode. Meanwhile, the LiDFOB additive form stable, uniform, and thin surface films simultaneously on positive and negative of the LiCoO 2 /graphite battery, inhibiting the electrolyte decomposition and leading to the improvement of the batteries performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The incorporation of NiS 2 into S@rGO via the self-assembly approach resulted in a unique S@rGO/NiS 2 NCs. • For an 84-minute period, the S@rGO/NiS 2 nanocomposite removes 96 percent of the MB dye. • S@rGO/NiS 2 nanocomposite outperformed other catalyst samples in terms of transient photocurrent responsiveness. • Even after the sixth recycle, the designed S@rGO/NiS 2 showed exceptional stability. Semiconductive materials that are activated by solar light and have a low e - and h+ pair recombination rate, a short bandgap, and fast charge carrier characteristics are effective organic pollution treatment catalysts. Synthesizing sulphur doped reduced graphene oxide/NiS 2 (S@rGO/NiS2) nanocomposites (NCs) for effective dye-degradation through photocatalysis under solar irradiation is the subject of this paper. S@rGO/NiS 2 NCs were made using a simple and efficient S@rGO nanosheets in NiS 2 solution technique. When bound to rGO, NiS 2 nanoparticles (NPs) act as an effective catalyst for the removal of methylene blue (MB) dye. SEM, EPR, FTIR, UV–vis, photocurrent responses, XRD, and EDX were used to characterize S@rGO/NiS 2 NCs. S@rGO/NiS 2 is predominantly utilized as a photocatalyst for photoreaction-based degradation of aqueous MB dye. The nanocomposite removes 96 percent of the MB dye in 84 min. The presence of NiS 2 NPs in the catalyst increases the formation of hydroxyl radicals (OH), which supports the photocatalytic process by suppressing electron (e -) and hole (h +) recombination, resulting in the destruction of organic contaminants. The catalyst's effectiveness is further tested by altering the pH of the MB solution medium. The reaction rate is pH dependent, with the quickest degradation time in the presence of S@rGO/NiS 2 NCs occurring at pH 8. The reusable catalytic characteristics of suspended S@rGO/NiS 2 NCs are investigated for six cycles, yielding a degradation efficiency of more than 93 percent in 84 min. Under sunlight, the antibacterial effectiveness of S@rGO/NiS 2 was investigated against Gram-positive and Gram-negative microorganisms. These promising findings could be used to purify polluted water from numerous sectors. [ABSTRACT FROM AUTHOR]

Surface modification of carbon fibres (CFs) is an important part of the interfacial study of CF composites. Traditional modification methods feature complicated production processes and a variety of influential factors. The modification technology utilized may cause fibre damage. To solve this problem, a simple and efficient CF surface modification method involving the in-situ carbonisation of micron-sized sucrose particles, is proposed in this paper. Sucrose crystals were introduced on the surface of the CFs by an ethyl acetate suspension coating and carbonised in atmosphere at moderate temperatures. Carbonisation of sucrose at 290 °C in air resulted in not only the formation of a large amount of C O content, but also in micron-sized particles. The attachment of these uniform and reactive particles to the CF surfaces resulted in a markedly improved impact resistance level of the carbon fibre reinforced polymer (CFRP) composite. Meanwhile, the interfacial shear strength (IFSS) and interlaminar shear strength (ILSS) of the carbonised sucrose-deposited fibre/epoxy composites increased by 20.8% and 13.8%, respectively. This method provides a novel, convenient, and effective approach to enhance the mechanical properties of high-performance CFRPs. Unlabelled Image • Micron-sized sucrose particles were introduced to the surface of CF by an ethyl acetate suspension coating and carbonised in air atmosphere to modify the interface between CF and epoxy resin in CFRP. • Interfacial properties between CFs and matrix were improved by the modification • The carbonised sucrose particles effectively enhanced the impact properties of CFs/epoxy composite. • Enhanced chemical interaction and mechanical interlocking can attribute to the mechanism of interface enhancement of CFRP. [ABSTRACT FROM AUTHOR]

Developing a simple and reliable method for the detection of the highly concerning antibiotic, Chloramphenicol (CAP), is of great importance to food safety monitoring. In this study, the authors take the advantages of polyethyleneimine-functionalized reduced graphene oxide and gold nanocubs (PEI-rGO/AuNCs) composite as electrode modification material to develop an electrochemical aptasensor for the detection of CAP using single-stranded DNA-binding protein. PEI-rGO/AuNCs warrants good electrical conductivity and a high surface-to-volume ratio to achieve the purpose of signal amplification. The CAP-binding aptamers were immobilized on the PEI-rGO/AuNCs modified gold electrode via Au-S affinity. Based on the property that single-stranded DNA-binding protein (SSB) can bind to free single-stranded oligonucleotides without binding to folded oligonucleotides, in the presence of CAP, only a small number of SSB will be immobilized on the aptasensor surface results in a larger peak current, which is typically measured at 0.176 V (vs. Ag/AgCl). The assay has a linear response in the 5 pmol·L−1 to 1 μmol·L−1 concentration range, with a 2.08 pmol·L−1 detection limit. Moreover, the proposed method has been applied to detect CAP in spiked chicken samples with satisfactory results. Unlabelled Image • Edges and vertices of AuNCs have more available reaction sites. • PEI-rGO/AuNCs can significantly improve aptasensor detection performance. • SSB provides a simple signal amplification aptasensor strategy. • Aptamer-based recognition element imparts sensor specificity. [ABSTRACT FROM AUTHOR]