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151.
152.
Multimedia Tools and Applications - In this paper we present a dataset of images to test the performance of image processing algorithms, in particular demosaicing and denoising methods. Despite the...  相似文献   
153.
A low‐temperature synthesis coupled with mild activation produces zeolite films exhibiting low dielectric constant (low‐k) matching the theoretically predicted and experimentally measured values for single crystals. This synthesis and activation method allows for the fabrication of a device consisting of a b‐oriented film of the pure‐silica zeolite MFI (silicalite‐1) supported on a gold‐coated silicon wafer. The zeolite seeds are assembled by a manual assembly process and subjected to optimized secondary growth conditions that do not cause corrosion of the gold underlayer, while strongly promoting in‐plane growth. The traditional calcination process is replaced with a nonthermal photochemical activation to ensure preservation of an intact gold layer. The dielectric constant (k), obtained through measurement of electrical capacitance in a metal–insulator–metal configuration, highlights the ultralow k ≈ 1.7 of the synthetized films, which is among the lowest values reported for an MFI film. There is large improvement in elastic modulus of the film (E ≈ 54 GPa) over previous reports, potentially allowing for integration into silicon wafer processing technology.  相似文献   
154.
Ground tire rubber (GTR) was modified by sulfuric acid in order to improve its compatibility with and reinforcement of a polypropylene (PP) matrix. Polymer composites PP/GTR were prepared by melt mixing at different concentrations, with a maximum of 50 wt % of GTR. Studies by Fourier transform infrared spectroscopy (FTIR), surface specific area by BET (Brunauer, Emmett, and Teller), and scanning electron microscopy were used to characterize the untreated GTR and treated GTR, while the mechanical and thermal properties of the PP/GTR composites were assessed to understand how the surface treatment of GTR affected the mechanical and thermal properties of the composite PP/GTR. FTIR revealed the presence of sulfonic groups on the surface of sulfuric acid–treated GTR, and BET analyses showed an increase of about 625% in the specific surface area as a result of the high porosity produced by the treatment. In all composites containing treated GTR, a higher Young's modulus was obtained than for composites containing untreated GTR. Particularly, an increase of about 275% in the Young's modulus was obtained in composites with treated GTR (40 wt %) against that containing untreated GTR. However, a more significant reduction of the elongation at break was observed in composites containing treated GTR than in those containing untreated GTR. Also, an increase of the crystallization temperature of PP as a function of GTR was observed by differential scanning calorimetry, but the crystallinity of the composites was reduced by the addition of both untreated and treated GTR. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44858.  相似文献   
155.
The taste responsiveness of six squirrel monkeys, five pigtail macaques, four olive baboons, and four spider monkeys to polycose, a starch-derived polysaccharide, was assessed in two-bottle preference tests of brief duration (2 min). In experiment 1, the monkeys were given the choice between tap water and defined concentrations of polycose dissolved in tap water. In experiment 2, the animals were given the choice between polycose and sucrose, fructose, glucose, lactose, and maltose presented in equimolar concentrations of 100 and 200 mM, respectively. The animals were found to prefer concentrations of polycose as low as 10 mM (pigtail macaques), 30 mM (olive baboons and spider monkeys), and 60 mM (squirrel monkeys) over tap water. Relative taste preferences were stable across the concentrations tested and indicate an order of relative effectiveness (sucrose > polycose maltose) in squirrel monkeys, spider monkeys, and olive baboons that is similar to the order of relative sweetness in humans. Pigtail macaques, however, displayed an order of relative effectiveness (maltose > polycose sucrose) that differs markedly from that found in the other primate species tested and is similar to relative taste preferences found in rodents such as rats. Both the high sensitivity of the pigtail macaques to polycose and their vivid predilection for this polysaccharide and its disaccharide constituent maltose suggest that Macaca nemestrina, unlike other primates, but like rodents, may have specialized taste receptors for starch.  相似文献   
156.
The effects of zinc deficiency and testosterone on fatty acid composition of plasma lipids and microsomes of liver, intestine and testes were studied. The activities of fatty acid desaturase (Δ6 and Δ5) in rat liver and testes were also measured. A significant decrease in the level of arachidonic acid was observed in plasma of normal rats fed the zinc-deficient diet. Castration significantly decreased arachidonic acid but increased 20∶3 fatty acid, which is negligible in normal rats. Testosterone and zinc administration restored arachidonic acid to normal values. Zinc deficiency does not significantly change the fatty acid profile in liver, but castration decreased both arachidonic and 22∶6 fatty acid. Intestinal mucosal microsomes showed that the predominant fatty acid in this tissue, palmitic acid, is independent of zinc status, whereas polyunsaturated fatty acids 18∶2 and 20∶4 were decreased by zinc-deficient diet or castration. Zinc deficiency sharply decreased 22∶5 fatty acid and to some extent, other polyunsaturated fatty acids in testis microsomes. These changes in fatty acids are in agreement with increased Δ9 desaturation and decreased Δ5 desaturase activity. In testes, both Δ6 and Δ5 desaturase activities are decreased in zinc deficiency. It appears that zinc influences the conversion of linoleic to arachidonic acid, whereas testosterone influences Δ6 desaturase activity. The data suggest that zinc deficiency may be one of the important factors in the causation of polyunsaturated fatty acid deficiency, which in turn, may induce serum hypertriglyceridemia.  相似文献   
157.
Lipase-catalyzed acidolysis of different TAG with CLA was performed to produce structured lipids (SL) containing CLA. An immobilized lipase from Mucor miehei (Lipozyme IM, Novo Nordisk Inc., Franklinton, NC) was used as the biocatalyst in a solvent-free system. Conconut oil and tricaprylin, which are sources of medium-chain FA, were the starting substrates, and a mixture of FFA (MFFA) containing 73% CLA was the donor of the acyl groups. For each TAG, four different ratios of TAG/MFFA were blended to prepare about 500 g of mixture containing 10, 20, 30, and 40% CLA (w/w). Each blend was reacted with 5% lipase at 65°C for 48 h under nitrogen. Over the range of TAG/MFFA ratios examined, CLA was incorporated effectively by the enzyme. Lipozyme IM exhibited no special preference for any particular FA, since the incorporation of FA was proportional to their concentration in the system. FFA, PV, p-anisidine value (p-AV), iodine value (IV), and saponification number (SN) were evaluated for all the SL. FFA, PV, and p-AV depended on the purification process and showed no significant deterioration of SL with respect to the original TAG, whereas IV and SN depended on the composition of the SL, mainly the CLA content.  相似文献   
158.
In recent years, the implementation of quality management systems based on ISO 9001 has clearly gone beyond the traditional industrial and service subsectors. It has started to have a growing influence on some peripheral subsectors to the standard home market, such as those of health and social services. In this article, the influence of the main global management meta‐standard is analyzed from a macroergonomic perspective in one of the aforementioned sectors. Based on an empirical exploratory study carried out in two Spanish organizations belonging to the subsector of residential care homes for elderly persons, the influence of the adoption of the standard is analyzed, focusing on the quality of working life of the direct attention employees. © 2012 Wiley Periodicals, Inc.  相似文献   
159.
Nanocomposites based on biodegradable poly(ε-caprolactone), (PCL) and organically modified layered silicates (organoclay) were prepared by melt mixing. The isothermal crystallization of PCL/clay nanocomposites at different clay concentrations (from 0.1 to 10 wt%) were investigated by differential scanning calorimetry (DSC) and rheometry in dynamic tests. The results showed that the well dispersed organoclay platelets acted as nucleating agents in the PCL matrix, as confirmed by a remarkable reduction of the crystallization half-time, t1/2. This effect was most pronounced at very low clay concentrations. In particular, in composites with 0.4% of clay, t1/2 was one order of magnitude lower than the pure polymer. The heating thermograms, performed on PCL and on PCL/clay after isothermal crystallization showed a reduction of the melting temperature with the increase of the clay content, suggesting that the degree of perfection of the crystals and the degree of crystallinity were affected by the restricted mobility of the chains, which did not allow the growth of well developed lamellar crystals. The rheological measurements confirmed the effect of clay on crystallization kinetics. The evolution of G′ and G″ vs. time was correlated to the clay concentration and to the development of the crystalline phase during isothermal experiments.  相似文献   
160.
A conceptual framework for proper identification of groups of species having a similar dynamic behavior is presented. The characterization of species similarity pursued is mostly based on an unobservable subspace condition of the reaction dynamics. This peculiarity facilitates the incorporation of physical insight. Partitioning of the original system is carried out by following the approach which defines species similarity with respect to a selected set σa of dynamic modes. In this way, dynamic similarity between species is examined in terms of the rows of an eigenbasis matrix V. Partitioning conditions upon which local dynamics in similar groups can be decoupled are formally established. Since in real reaction systems the components are seldom exactly similar, we also develop a near-similar grouping concept. Keeping in mind large-scale systems partitioning, the basis of an approximate algorithm using Gaussian elimination are also presented.  相似文献   
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