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Subsequent Heating (subsequent + heating)
Selected AbstractsTunable Nanowrinkles on Shape Memory Polymer SheetsADVANCED MATERIALS, Issue 44 2009Chi-Cheng Fu Controllable biaxial and uniaxial nanowrinkles (see figure) are fabricated by a simple two-step approach , metal deposition and subsequent heating , based on shape memory polymer (prestressed polystyrene) sheets. The wavelengths of the wrinkles can be tuned by controlling the thickness of deposited metal. The ready integration of the nanowrinkles into microchannels and their effectiveness in surface enhanced sensing is demonstrated. [source] CORRELATION BETWEEN CITRIC ACID, THYMUS VULGARIS EXTRACT AND NaCl, AND HEAT SENSITIVITY AND CASEINASE PRODUCTION BY AEROMONAS CAVIAE AND A. SOBRIAJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2008BAYAN M. ABU-GHAZALEH ABSTRACT The effects of citric acid, Thymus vulgaris extract and NaCl on the heat sensitivity of Aeromonas spp. were examined in three different situations in this study. First, the effects of pretreatment with nutrient broth plus 0.03% citric acid, nutrient broth plus 0.3% T. vulgaris extract, nutrient broth plus 2.5% NaCl or nutrient broth plus 3% NaCl on the survival and caseinase production by heated A. caviae 166 and A. sobria 74 were investigated. Pretreatment of Aeromonas spp. with these preservatives for 1 or 6 days significantly increased their resistance to subsequent heating at 54C. However, pretreatment of Aeromonas strains with nutrient broth plus 2.5% NaCl or nutrient broth plus 3% NaCl before heating at 54C significantly (P < 0.05) decreased the production of caseinase by the heated cells. Second, the effect of post-treatment with preservatives after heating of Aeromonas strains was examined. Post-treatment of Aeromonas strains with the tested preservatives for 7 days after heating at 54C for 20 min prevented a complete recovery of cells and decreased the caseinase production compared with Aeromonas cells that were incubated in nutrient broth alone for 7 days after heating at 54C. Third, the effect of the type of the heating menstruum on the heat sensitivity of Aeromonas strains was investigated in this study. Heating in NaCl (0.85%) containing citric acid (0.03%) was the most effective treatment in killing Aeromonas spp. Heating in NaCl (0.85%) containing T. vulgaris extract (0.3%) or in NaCl (3.85%) slightly increased the resistance of cells to heat. PRACTICAL APPLICATIONS The results obtained in this study can be applied in the food industry, where combination of mild heat treatment and addition of low doses of chemical preservatives to food is nowadays frequently used. This study determined the heat sensitivity and caseinase production by A. caviae and A. sobria at three different conditions that may be encountered during processing of food industrially or at home. Firstly, the effect of pretreatment with some preservatives on the heat sensitivity and caseinase production by the tested Aeromonas. spp. was studied. Secondly, the effect of post-treatment with preservatives on growth and caseinase production by the heated (54C) Aeromonas cells was investigated. Thirdly, effect of presence of preservatives in the heating menstruum on the heat sensitivity of Aeromonas spp. was studied. [source] Reproducible Solvent,Thermal Synthesis, Controlled Microstructure, and Photoluminescence of REPO4:Eu3+, Tb3+ (RE=Y, La, and Gd) NanophosphorsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2010Xiuzhen Xiao By altering the temperature and solvents, we have synthesized hydrated and dehydrated Eu3+/Tb3+ -doped REPO4 (RE=Y, La, and Gd) nanophosphors via a solvo-thermal technology. X-ray powder diffraction and scanning electronic microscopy reveal that they have different structures and different morphologies. REPO4 prepared under subsequent heating at 80°, 120°, and 160°C for 1 day, respectively, present larger particle size than that formed by heating at 160°C for 3 days. Moreover, at the same temperature of 160°C and pH 3, three different solvents (ethanol, N,N -dimethylformamide (DMF), and water) were used, whose influence on the microstructure of LaPO4 has been examined. As a result, LaPO4 samples from anhydrous ethanol solvent show a pure hexagonal phase and nanowire morphology, just like that prepared from the water solvent. On the other hand, the microstructure of LaPO4 samples from DMF,H2O-mixed solvents have been changed: with the increasing volume ratio of DMF to H2O, the crystal phase of LaPO4 has been changed from hexagonal phase to monoclinic phase and the morphology from nanowires to nanoparticles. Finally, the photoluminescence properties of these Eu3+ (Tb3+)-activated rare earth phosphates have been investigated, indicating that the photoluminescent behavior are related to their crystal phases and microstructures. [source] Preferred Orientation of Bi4Ti3O12 Thick FilmJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2007Yoshiaki Kinemuchi The preferred orientation of thick films prepared by paste printing is rarely observed because of their bulky polycrystalline nature. We found that a Bi4Ti3O12 thick film with a thickness of ca. 20 ,m showed c -axis-preferred orientation. Initially, the texture of the screen-printed film was found to have a random orientation, which was attributed to the equiaxed particle shape of the raw powder synthesized by the co-precipitation method. During subsequent heating, c -axis orientation emerged in which the degree of orientation was proportional to the film density. Analysis of the orientation distribution revealed that the progress of texturing was attributed to the film deformation, indicating that anisotropic shrinkage and morphological changes in particles during heating influenced the preferred orientation. [source] Synthesis of Phase-Pure Pb(ZnxMg1,x)1/3Nb2/3O3 up to x= 0.7 from a Single Mixture via a Soft-Mechanochemical RouteJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2000Seiji Shinohara Phase-pure perovskite Pb(ZnxMg1,x)1/3Nb2/3O3 solid solution (PZxM1,xN) is obtained for x, 0.7 by heating a milled stoichiometric mixture of PbO, Mg(OH)2, Nb2O5, and 2ZnCO3·3Zn(OH)2·H2O at 1100°C for 1 h. Percent perovskite (fP) with respect to total crystalline phase decreases with increasing temperature of subsequent heating then increases to 900°C for the mixtures where x, 0.8 and milled for 3 h. For mixtures with x= 0.9 and x= 1, fP decreases monotonically. Curie temperature increases almost linearly with increasing x up to x= 0.7. The maximum dielectric constant at 1 kHz is 2×104 and 1.7×104 for the mixture with x= 0.4 and x= 0.7, respectively. The stabilization mechanism of strained perovskite is discussed. [source] | ||||||||||