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F lammulina velutipes ready-to-eat snacks are not commonly known. Response surface methodology was employed to optimize the process parameters in making ready-to-eat snacks. The optimum dehydration condition was found at a sucrose concentration of 30%, a vacuum pressure of −40 ± 1.5 kPa, an osmotic time of 165 s and a microwave intensity of 65 W/g. These parameters resulted in water loss, solid gain and sensory evaluation values of 39.15%, 6.96% and 7.87, respectively. The water diffusion rate and solid gain diffusion rate were 1.55 × 10−9 and 1.29 × 10−9 m2/s, respectively, when employing the optimum microwave vacuum osmotic dehydration ( MVOD) parameters. When F . velutipes mushrooms were dried for 180 min by hot-air drying, the water content of the ready-to-eat snack was 9.8 ± 0.5% and the water diffusion rate was 1.14 × 10−11 m2/s. Both the MVOD and the hot-air drying stages were consistent with the Page model. Practical Applications Osmotic dehydration technology combined with other drying technologies, such as hot air, can improve the use value and economic benefits of fruits and vegetables. The two correlations developed by modifying second-order polynomial equations were adequate to predict the responses for the F lammulina velutipes samples. The water and solid effective diffusion rates were calculated at different microwave vacuum osmotic dehydration times and different hot-air drying times for F . velutipes mushrooms. The Page model could be used to illustrate the water loss and solid gain for these two drying stages. The F . velutipes mushroom snacks made using these conditions had good color, high gloss and a moderately soft texture, with a sweet and sour flavor. The developed mathematical models can be considered precise for the prediction and optimization of process parameters in experimental and industrial applications. [ABSTRACT FROM AUTHOR]

xZrO2–(1−x)TiO2 (0≤x≤0.7) nanocrystals were prepared by sol–gel method. The prepared pure and composite powders were characterized by differential thermal analysis-thermogravimetry (DTA–TG), X-ray diffraction (XRD), transmission electron microscopy and electron diffraction (TEM and ED), and the photoluminescence (PL) properties of the composite nanocrystals were studied for the first time. The results showed that nanocrystals were obtained. Their crystalline size and phase composition were dependent on the ZrO2 content. ZrO2 addition suppressed the crystal growth of TiO2. The emission peak position of the composite nanocrystals heat-treated to 550 °C had 8 nm red-shift and their emission intensity became stronger compared with that of pure TiO2. The most intense emission appeared in 0.4ZrO2–0.6TiO2, which is about 2.4 times of pure TiO2 nanocrystals. [Copyright &y& Elsevier]

TiO2/ZrxTi1−xO2 composite films have been prepared by sol–gel method and their photocatalytic activity and stability have been investigated for the first time. Their surface morphology and average surface roughness are characterized by AFM. TiO2 P25 and pure sol–gel TiO2 films have also been prepared and investigated for comparison. Films with smaller crystallite size and larger surface roughness have been obtained by introduction of ZrxTi1−xO2 intermediate layers between TiO2 layers and substrate in the composite films. The results show that the photocatalytic activity and stability of the composite films are higher than those of pure sol–gel TiO2 and TiO2 P25 films. [Copyright &y& Elsevier]

Ni2+ doped ZrO2 nanocrystals have been prepared by a urea-containing coprecipitation method. The photoluminescence of the doped samples was investigated in detail. Upon excitation at 483 nm, a red emission band at 612 nm was observed originating from the 1T2 (1D)–3T2 (3F) transition of Ni2+. Effects of both heat-treated temperature and doping concentration on the luminescent properties were also studied. The results reveal that a concentration quenching of the luminescence occurs as the molar ratio of Ni2+ exceeds the optimum value (1%). However, no thermal quenching was observed probably due to the improved crystallinity of the host lattice resulting from the increase of the calcining temperature. [Copyright &y& Elsevier]

SnO2 thin films have been grown on soda-lime glass substrate using a simple spin-coating method. The films grown under different calcining temperatures have been characterized using microstructural and luminescent measurements. Room-temperature photoluminescence measurements under excitation at 280 nm show two broad emission peaks, the one peaking at 430 nm can be related to tin interstitials or dangling, and the other at 400 nm can be related to oxygen vacancies in the SnO2 thin films. [Copyright &y& Elsevier]

Nanocrystalline ZrO2 particles doped with Dy3+ ions have been synthesized by a simple co-precipitation method. The structural and optical properties of Dy3+-doped ZrO2 particles are investigated using the X-ray powder diffraction, transmission electron microscopy, and photoluminescence spectroscopy. The photoluminescence characteristics originating from Dy3+-doping in the ZrO2 nanoparticles were systematically investigated. Experimental results reveal that the luminescence can be affected by both the calcining temperature and the Dy3+ concentration in the ZrO2 nanoparticles. [Copyright &y& Elsevier]

Nanometer scale cubic ZnTiO3 has been synthesized by sol–gel method at a lower temperature (600 °C). X-ray diffraction (XRD) analysis shows that the average crystalline size of the sample is ∼8–10 nm. The cubic to hexagonal phase transition of ZnTiO3 is clearly observed from the XRD patterns of the sample. The thermal behavior of the sample was characterized by the thermogravimetric/differenthermal analysis (TG/DTA), XRD patterns, and the infrared spectra (IR). Transmission electron microscope (TEM) observations of the sample reveal a high microstructural uniformity. [Copyright &y& Elsevier]

Ni2+-doped SiO2, Al2O3–99SiO2 glasses have been prepared by sol–gel method. The effect of Al3+ on the photoluminescence (PL) properties of Ni2+-doped SiO2 has been studied. Ni2+-doped sol–gel SiO2 glass shows an emission band at 510 nm, which is attributed to the d–d transition 1T2(1D)→3A2(3F) of Ni2+ in octahedral sites. The emission of Ni2+ ions is greatly enhanced by the addition of Al3+ into SiO2. The study on Fourier transform infrared spectroscopy (FT-IR) and UV–Vis absorption spectra shows that the glass network and coordination environment of Ni2+ are changed after adding Al3+ into SiO2. [Copyright &y& Elsevier]