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71.
Multidimensional Systems and Signal Processing - Reversible data hiding in the encrypted domain has attracted a lot of consideration because of the necessity for content security and protection...  相似文献   
72.
This article describes the effect of filler [obtained from bark of Acacia (Babool)] content and its particle size (ranging from 100 to 150 μm and <50 μm) on the properties of poly(vinyl chloride) (PVC) composites. Bark of the fast‐growing species Acacia was used as powder for making PVC composites, which may find applications as a substitute to high‐cost wood and to avoid deforestation. A two‐roll mill was used for mixing varying amounts of bark flour with PVC formulation. Samples for testing were prepared by compression molding. Tensile strength and percentage of elongation at break decreased, whereas modulus increased with an increasing amount of bark flour. A significant increase in storage modulus (E′) was observed upon incorporation of filler. Improvement in properties was significant in the presence of filler, having a particle size <50 μm as compared to filler, having a particle size ranging from 100 to 150 μm. Morphological characterization was conducted by using scanning electron microscopy. A uniform dispersion of filler was observed in PVC matrix. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
73.
Chickpea is an important food legume and is a major ingredient in many human diets. Chemical composition, physical parameters, functional properties and microstructural characteristics of three kabuli chickpea cultivars and the effects of three cooking methods were investigated. Carbohydrate and protein were two major components in all seeds. Cooking increased fibre, total carbohydrate and total and resistant starch contents, but decreased ash content. Protein and oil levels of the cooked samples either decreased or did not change significantly. Seed weight and density decreased with cooking. Hydration and swelling capacities as well as water absorption and holding capacities of cooked chickpeas were higher than raw samples, with the largest increases in the pressure‐cooked seeds. Seed weights were highly correlated with hydration (= 0.89) and swelling (= 0.76) rates. Emulsifying activity, emulsifying stability and foaming capacity of cooked chickpea flours decreased, while foaming stability increased. Chickpea flours had pronounced morphological changes after cooking.  相似文献   
74.
Paper coating pigment plays an essential role in the achievement of the desired end paper qualities. Different pigment varieties are available for paper coating. Ground calcium carbonate (GCC) is the major one used frequently in coating formulations. Precipitated calcium carbonate (PCC) is gradually gaining importance in paper coating, as it can be prepared in different shapes and sizes. The present study was carried out to determine the influence of PCC pigments with different shapes and sizes on paper properties, and their limitations and advantages when blended with finer grade GCC. PCC pigments of calcite and aragonite crystalline polymorphs having rhombohedral, orthorhombic, and scalenohedral habits were selected for the study. It was observed that the viscosity and water-holding capacity of the coating color was reduced with the introduction of PCC in the coating formulation. The PCC pigments showed greater light scattering, opacity, and smoothness of the coated paper as compared to the GCC pigment. The clustered (rosette) shape of scalenohedral habit calcite PCC results in the greatest light scattering, opacity, and surface strength amongst all PCCs. The aragonite PCC of orthorhombic habit and calcite PCC of rhombohedral habit show an almost similar trend in coated paper properties with the greatest smoothness and paper gloss.  相似文献   
75.
IR接近检测传感器广泛用于检测物体是否存在,与参照物之间的距离,或同时检测两者.具体应用包括:测速、自控式水龙头,自动计数器或传送带物体检测,打印机纸张边缘检测等其它应用.  相似文献   
76.
Gradually increasing temperatures at global and local scales are causing heat stress for cool and summer-season food legumes, such as lentil (Lens culinaris Medik.), which is highly susceptible to heat stress, especially during its reproductive stages of development. Hence, suitable strategies are needed to develop heat tolerance in this legume. In the present study, we tested the effectiveness of heat priming (HPr; 6 h at 35 °C) the lentil seeds and a foliar treatment of γ-aminobutyric acid (GABA; 1 mM; applied twice at different times), singly or in combination (HPr+GABA), under heat stress (32/20 °C) in two heat-tolerant (HT; IG2507, IG3263) and two heat-sensitive (HS; IG2821, IG2849) genotypes to mitigate heat stress. The three treatments significantly reduced heat injury to leaves and flowers, particularly when applied in combination, including leaf damage assessed as membrane injury, cellular oxidizing ability, leaf water status, and stomatal conductance. The combined HPr+GABA treatment significantly improved the photosynthetic function, measured as photosynthetic efficiency, chlorophyll concentration, and sucrose synthesis; and significantly reduced the oxidative damage, which was associated with a marked up-regulation in the activities of enzymatic antioxidants. The combined treatment also facilitated the synthesis of osmolytes, such as proline and glycine betaine, by upregulating the expression of their biosynthesizing enzymes (pyrroline-5-carboxylate synthase; betaine aldehyde dehydrogenase) under heat stress. The HPr+GABA treatment caused a considerable enhancement in endogenous levels of GABA in leaves, more so in the two heat-sensitive genotypes. The reproductive function, measured as germination and viability of pollen grains, receptivity of stigma, and viability of ovules, was significantly improved with combined treatment, resulting in enhanced pod number (21–23% in HT and 35–38% in HS genotypes, compared to heat stress alone) and seed yield per plant (22–24% in HT and 37–40% in HS genotypes, in comparison to heat stress alone). The combined treatment (HPr+GABA) was more effective and pronounced in heat-sensitive than heat-tolerant genotypes for all the traits tested. This study offers a potential solution for tackling and protecting heat stress injury in lentil plants.  相似文献   
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78.
Wireless Personal Communications - For the precise positioning applications it is important to determine and eliminate the positioning error introduced by various sources such as the ionosphere. To...  相似文献   
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