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Abstract: The amorphous MoS2 nanoparticles have been synthesized by a simple oxidation–reduction reaction in an aqueous solution. A series of products with different morphologies, such as MoS2 nanospheres, inorganic fullerene-like nanospheres, nanorods and Mo bended rods, can be obtained by annealing the amorphous MoS2 nanoparticles under N2 atmosphere under 400–1200°C. These products have been characterized by X-ray diffraction, field emission scanning electronic microscopy, transmission electron microscopy and high-resolution transmission electron microscopy in detail. The possible transformation mechanism for the structure has been discussed based on the experimental results. In addition, the optical properties of IF-MoS2 have also been performed by UV–vis absorption spectroscopy. [Copyright &y& Elsevier]

Abstract: W/WS2 inorganic fullerene-like (IF) nanoparticles with core–shell structure are synthesized by the reaction of tungsten nanospheres and sulfur at relatively low temperatures (380–600°C) under hydrogen atmosphere, in which tungsten nanospheres were prepared by wire electrical explosion method. Images of transmission electron microscopy and high-resolution transmission electron microscopy show that the composite particles are of core–shell structure with spherical shape and the shell thickness is about 10nm. X-ray powder diffraction results indicate that the interlayer spacing of IF-WS2 shell decreases and approaches that of 2H-WS2 with increasing annealing temperatures, representing an expansion of 3.3–1.6%. A mechanism of IF-WS2 formation via sulfur diffusion into fullerene nanoparticles is discussed. Thermal analysis shows that the nanoparticles obtained at different temperatures exhibit similar thermal stability and the onset temperature of oxidization is about 410°C. Encapsulating hard tungsten core into IF-WS2 and the spherical shape of the core–shell structures may enhance their performance in tribological applications. [Copyright &y& Elsevier]

Abstract: TiO2/SrFe12O19 composite nanoparticles with core-shell structure have been obtained. The core SrFe12O19 nanoparticles were synthesized by citrate precursor technique with Fe/Sr ratio of 10.8, and then the shell TiO2 nanocrystals were derived via sol–gel technology. The presence of a small amount of polyethyleneimine (PEI) on the surface of the strontium ferrite nanoparticles facilitates this coating process. The morphology, crystalline structure, particle size and size distribution of TiO2/SrFe12O19 composite nanoparticles were characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and 3000HSA analyzer (MALVERN), respectively. Energy-dispersive spectroscopy (EDS) was utilized for the elemental analysis of the products. The as-prepared composite particles can be utilized as a magnetic photocatalyst, which can be fluidized and recovered by an applied magnetic field enhancing both separating and mixing efficiency for recyclable fluids. Magnetic properties and photocatalytic activities of these powders have been evaluated. The result of the experiments shows that the saturation magnetizations of titania-coated SrFe12O19 nanoparticles decrease as increasing the thickness of the titania coating, while the coercivity does not show any change after coating. Photocatalytic activities of these powders increase with increasing the thickness of TiO2 coating layer. [Copyright &y& Elsevier]

Abstract: The spherical nickel nanoparticles (an average diameter of 75nm) were prepared by wire electrical explosion method, and silica was coated on nickel forming complete coverage by the controlled hydrolysis and condensation of tetraethyl orthosilicate (TEOS). The method was based on the use of silane coupling agent 3-mercaptopropyltrimethoxysilane (HS-(CH2)3Si(OCH3)3, MPTS) as a primer to render the nickel surface vitreophilic, thus rendering nickel surface compatible with silica. The thickness of SiO2 coating layer increases with the increasing reaction time. The nickel nanoparticles and the nickel coated with silica shell were confirmed by transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) was used to gain insight into the way in which the MPTS is bound to surface of the nickel nanoparticles. Result of the thermogravimetric analysis (TGA) and differential thermal analysis (DTA) indicate that the thermal stability of nickel/silica is better than of pure nickel nanoparticles. Magnetic properties of these powders have been evaluated. These nickel/silica core–shell nanoparticles can be utilized as precursors for making property-tunable magnetic nanoparticles, thin films, and multilayered core–shell structure nanocomposites. [Copyright &y& Elsevier]

Objective: Numerous systematic reviews of prospective studies on the association of stroke risk with the consumption of various food groups have been published. A review of the evidence across the existing systematic reviews and meta-analyses of prospective studies was conducted to provide an overview of the range and validity of the reported associations of food groups with stroke risk.Design: The PubMed, EMBASE and Cochrane Library databases were searched for articles published up to September 2015 to identify systematic reviews of prospective studies.Results: A total of eighteen studies published from 2008 to 2015 were eligible for analysis. Overall, thirteen specific foods were studied for an association with stroke outcome, including nuts, legumes, fruits and vegetables, refined grains, whole grains, dairy products, eggs, chocolate, red and/or processed meat, fish, tea, sugar-sweetened beverages and coffee. Whereas a high consumption of nuts, fruits, vegetables, dairy foods, fish and tea, and moderate consumption of coffee and chocolate demonstrated a protective effect, a high consumption of red and/or processed meat was associated with increased stroke risk. Refined grain, sugar-sweetened beverage, legume, egg and whole grain intake showed no effect on stroke outcome.Conclusions: The current overview provided a high level of evidence to support the beneficial effect of specific foods on stroke outcome. Clinicians and policy makers could inform clinical practice and policy based on this overview. [ABSTRACT FROM AUTHOR]

Abstract: Large quantities of single crystalline magnesium borate nanowires of the form Mg2B2O5 with typical diameter about 120–180nm and length about 0.2mm have been successfully synthesized by a new and simple method of heating the mixed tablet of Mg(BO2)2 and graphite directly in vacuum at 1200°C for 1h. The products have been characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectrometry and selected area electron diffraction. The process of the nucleation and the growth of nanowires have been analyzed by VS mechanism. The results of the lubricating properties show that the friction coefficient of the oil is significantly decreased by the addition of Mg2B2O5 nanowires. Our results indicate that the new method we use is effective in synthesis of Mg2B2O5 nanowires and the nanowires can be used as additive to antiwear nanodevices. [Copyright &y& Elsevier]

Abstract: With ultrasonic irradiation as assistance, highly dispersed MoO3 nanospheres were synthesized using silane coupling agent 3-mercaptopropyltrimethoxysilane HS-(CH2)3Si(OCH3)3 (MPTS) as figuration agent. The results of X-ray powder diffractometer (XRD) showed that the precursor was hexagonal molybdenum oxide hydrate (MoO3 0.55H2O). It was converted into orthorhombic MoO3 after annealed at 400°C for 2h. Transmission electron microscopy (TEM) showed that MoO3 ·0.55H2O and MoO3 nanoparticles were spherical with particle-size distribution of ca. 30–80nm and 25–75nm, respectively. Results indicated that MPTS and ultrasonic irradiation played important role in formation of highly dispersed MoO3 nanospheres. X-ray photoelectron spectroscopy (XPS) was also adopted to confirm the growth mechanism. The possible cause of formation was based on dispersion function of ultrasonic irradiation and figuration of MPTS. [Copyright &y& Elsevier]

Abstract: SiC/ZnO nanocomposites were synthesized via a two-stage process. SiC nanoparticles were synthesized by electrical explosion method, and using the SiC nanoparticles as precursor, SiC/ZnO nanocomposites were synthesized by co-precipitation processes. The SiC/ZnO nanocomposites exhibit energy tuning of band-to-band transitions. In addition to the UV emission, the green and orange emissions were also observed. To our interest the green and orange emissions decreased at first and then increased with increasing annealing temperature. The underlying mechanism is elucidated. [Copyright &y& Elsevier]

Abstract: MoS2 films were prepared by chemical bath deposition using Ni interlayer, which was deposited electrolessly on Si substrates. The combined techniques of X-ray diffraction, field emission scanning electron microscope (FESEM), Raman spectroscopy and optical reflective spectra were used for characterization of MoS2 films at different conditions. Results indicated that the type-II MoS2 films oriented with their c axis perpendicular to the plane of Si substrates were obtained at annealing temperature greater than 800°C. The effect of nickel on the orientation of 2H–MoS2 crystallites can be explained on the basis of binary Ni–S phase diagram. The thin films have a direct optical bandgap of 1.87eV as a result of optical reflective spectra. This article offers an easy way to prepare type-II MoS2 film of better crystallite. [Copyright &y& Elsevier]

Abstract: The composite of hollow glass microspheres coated by SnO2 nanoparticles has been successfully fabricated via sol-gel method. The phase structures, morphologies, particle size, shell thickness, chemical compositions of the composite have been characterized by XRD, FESEM, and EDX. The results show that SnO2 coating on hollow glass microspheres can be achieved, and the coating layers are constituted by SnO2 nanoparticles of mean size ca. 15 nm. The SnO2 coating layers grow thicker with the increased concentration of SnCl4. The effects of parameters (reaction temperature, concentration of NaOH and SnCl4, and time) were investigated to yield SnO2 coating on hollow glass microspheres, and the UV–vis absorption spectra of the composites were studied. [Copyright &y& Elsevier]

Abstract: Transparent and conductive high preferential c-axis oriented ZnO thin films doped with yttrium have been prepared by sol–gel method using zinc acetate and yttrium chloride as cations source, 2-methoxyethanol as solvent and monoethanolamine (MEA) as sol stabilizer. Film deposition was performed by dip-coating technique at a withdrawal rate of 6.0 cm/min on silica glass substrates. The effect of dopant (Y) concentration, heating treatment and annealing in a reducing atmosphere on the structure, morphology, electrical and optical properties of ZnO thin films were investigated. When compared with the resistivity values of films without the annealing treatment, the values of films annealed in the reducing atmosphere were decreased by about three orders of magnitude. The lowest resistivity value was 6.75×10−3 Ω cm, which was obtained in the 0.5 at.% yttrium-doped ZnO thin film annealed in nitrogen with 5% hydrogen at 500 °C. The average optical transmittance values of the annealed films were more than 80% in the visible range. The energy band gap calculated from the transmittance spectra is about 3.30–3.37 eV. [Copyright &y& Elsevier]

Abstract: A novel core–shell structure material, Cu–Zn/ZnO, was prepared by a surface modification precipitation process in aqueous solution at low temperature. A nucleation and crystal growth model for this structure was proposed. The resultant nanocomposites were characterized by X-ray diffraction, transmission electron microscope, field emission scanning electron microscope and photoluminescence spectroscope. Results showed that 20–50nm thick ZnO shell was obtained on the surface of Cu–Zn nanopowders directly in the aqueous solution at 40°C during the precipitation process and as-synthesized materials have a strong ultraviolet luminescence peak around 379–390nm, but no usual defect-related emissions in visible range. The quantum confinement effect of ZnO nanocrystals, the presence of Cu and Zn atoms and absence of defects in ZnO layer are believed responsible for the characteristics of the photoluminescence spectra. [Copyright &y& Elsevier]

Abstract: A core-shell structure TiO2/BaFe12O19 composite nanoparticles that can photodegrade organic pollutants in the dispersion system effectively and can be recycled easily by a magnetic field is reported in this paper. The obtained samples were characterized by energy dispersive X-ray spectroscopy (SEM-EDS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The TiO2/BaFe12O19 magnetic photocatalyst is composed of two parts: (1) TiO2 shell used for photocatalysis and (2) BaFe12O19 core for separation by the magnetic field. The photocatalytic activity of the as-prepared magnetic photocatalyst increased with increasing the thickness of TiO2 coating layer. On the other hand, the saturation magnetizations of titania-coated BaFe12O19 nanoparticles decreased with increasing thickness of the titania coating, while the coercivity does not show any change after coating. [Copyright &y& Elsevier]

Abstract: The composites of hollow glass microspheres (HGMS) coated by zinc oxide (ZnO) nanorods (HGMS/ZnO) were obtained by the controlled doubled-jet precipitation method in an ethanol–water solution. The particle-size, morphology, crystal structure and optical properties of the as-prepared HGMS/ZnO composites were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and room-temperature photoluminescence (PL) spectra. Moreover, we propose the mechanism that the hollow glass microspheres are modified with triethanolamine to obtain ZnO-coated composites. This method can also be applied to other substrates forming continuous films with highly ordered ZnO nanorods across the films. [Copyright &y& Elsevier]