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SiO 2 /Ge:SiO 2 /SiO 2 sandwiched structure was fabricated for exploring efficient light emission. After annealed in N 2 (O 2 Ͻ1%), this structure shows three photoluminescence ͑PL͒ bands at 293, 395, and 780 nm. The intensity of the 395 nm band is largely enhanced in comparison with that from the monolayered Ge:SiO 2 film. Spectral analyses suggest that the three PL bands originate from S 1 →S 0 , T ͚ (T ͟)→S 0 , and T ͟ Ј →S 0 optical transitions in GeO color centers, respectively. The improvement of the GeO density resulting from the confinement on Ge diffusion is responsible for the enhanced ultraviolet PL. This structure is expected to have important applications in optoelectronics.

Polystyrene/titanium dioxide (TiO 2 ) composite particles containing organic ultraviolet (UV)-stabilizer groups were prepared by the emulsion copolymerization of styrene and 2-hydroxy-4-(3-methacryloxy-2-hydroxylpropoxy)benzophenone with sodium sulfopropyl lauryl maleate as a surfactant in the presence of rutile TiO 2 modified with 3-(trimethoxysilyl) propyl methacrylate, and the product was poly[styrene-co-sodium sulfopropyl lauryl maleate-co-2-hydroxy-4-(3-methacryloxy-2-hydroxylpropoxy) benzophenone] [poly(St-co-M12-co-BPMA)]/TiO 2 composite particles. The structures of the composite particles were characterized with Fourier transform infrared spectroscopy, ultraviolet-visible (UV-vis) absorption spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The Fourier transform infrared and UV-vis measurements showed that poly(St-co-M12-co-BPMA) was grafted from the surface of TiO 2 , and this copolymer possessed a high absorbance capacity for UV light, which is very important for improving the UV resistance of polystyrene. The thermogravimetric analysis measurements indicated that the percentage of grafting and the grafting efficiency could reach 513.9 and 59.9%, respectively. The differential scanning calorimetry measurement indicated that the glass-transition temperature of the poly(St-co-M12-co-BPMA)/TiO 2 composite particles was higher than that of poly (St-co-M12-co-BPMA).These research results are very important for preparing polystyrene with high UV resistance.

The long-afterglow phosphor SrAl 2 O 4 : Eu 21 , Dy 31 is liable to hydrolyze in water with deterioration of its luminescent properties. In this study, in situ emulsion polymerization was first used to prepare phosphor coated with poly(methyl methacrylate-co-butyl acrylate) [P(MMA-co-BA)] to improve water resistance. Fourier transform infrared spectra suggested that the polymer attached to the phosphor by chemical bonding. Observation by scanning electron microscopy (SEM) showed that a polymer layer formed on the surface of the phosphor. The resistance to water of the phosphor coated with the polymer layer was much better than that of the uncoated phosphor because the transparent polymer layer could suppress its hydrolysis process. Low-density polyethylene (LDPE) plastics, doped with long-afterglow phosphors, were manufactured with an extrusion technique. Through coating with P(MMA-co-BA), the compatibility of phosphor with the LDPE matrix was improved, as determined by SEM. The luminous LDPE plastics blended with the phosphor coated with polymer showed long and strong phosphorescence with little loss of persistence phosphorescence compared to the uncoated phosphor. The LDPE plastics still retained their mechanical properties through doping with 3% (mass fraction) of the phosphors.

In this paper, poly(methyl methacrylate-co-sodium sulfopropyl lauryl maleate-co-2-hydroxy-4-(3-methacryloxy-2hydroxylpropoxy) benzophenone)/TiO 2 (i.e., poly(MMA-co-M12-co-BPMA)/TiO 2 ) composite particles were prepared by ultrasonically initiated emulsion polymerization. To study the dispersion and UV-stability of the composite particles, laser diffraction particle size analyzer (LDPSA), ultraviolet-visible absorption spectroscopy (UV-vis), UV-vis diffuse reflectance spectroscopy (DRS), differential scanning calorimeter (DSC), and the weight loss measurement were used. The results indicate that the dispersion of the poly(MMA-co-M12-co-BPMA)/TiO 2 composite particles prepared by ultrasonically initiated emulsion polymerization is good. And the composite particles can absorb UV light; the ultraviolet absorption strength of poly(MMA-co-M12-co-BPMA) grafted onto the surface of TiO 2 has not changed after UV irradiation while that of PMMA changed significantly. The UV absorption strength, weight loss, and Tg changes are in the order PMMA> poly(MMA-co-M12-co-BPMA) >PMMA grafted onto TiO 2 > poly(MMAco-M12-co-BPMA) grafted onto TiO 2 . These results show that the ultrasonically initiated emulsion polymerization will enhance the UV stability of composite particles, and the UV-stability of PMMA can be enhanced by the introduction of the organic UV-stabilizer BPMA and the inorganic UV-stabilizer titanium dioxide into the PMMA chains by covalent bond, and the effect of the BPMA and the TiO 2 used together is better than that used, respectively.

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As a key link in the whole process of Baijiu production, the traditional blending method, which mainly relies on manual experience, has some shortcomings, such as obvious quality fluctuation, difficulty in cost control and low blending efficiency, in the market environment with increasing demand and increasingly stringent quality. Therefore, the Baijiu blending control system was designed to realize the intelligentization of Baijiu blending. The Baijiu blending formula model was established based on the sensory evaluation data and physical and chemical index data of Baijiu. A top-down control system composed of information system layer, blend operation station, PLC programmable controller and field equipment layer; It is characterized by integration from formula design to target Baijiu production. The automatic control in the production process is realized, which guarantees the stability of Baijiu quality, improves the efficiency of Baijiu production, reduces the production cost, and promotes the modernization level of Baijiu productiont.