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991.
The starches separated from thirteen different black gram cultivars were investigated for physicochemical, thermal, morphological and pasting properties. Amylose content, swelling power, solubility and water binding capacity of starches ranged between 30.2–34.6%, 16.0–22.3 g/g, 14.8–17.3% and 73.5–84.5%, respectively. The diameter of starch granules, measured using a laser‐light scattering particle‐size analyzer, varied from 12.8 to 14.3 μm in all black gram starches. The shape of starch granules varied from oval to elliptical. The transition temperatures (To, Tp and Tc) and enthalpy of gelatinization (ΔHgel) determined using differential scanning calorimetry, ranged between 66.1–71.3, 71.0–76.2, 75.9–80.4°C and 6.7–9.4 J/g, respectively. Pasting properties of starches measured using the Rapid Visco Analyser (RVA) also differed significantly. Pasting temperature, peak viscosity, trough, breakdown, final viscosity and setback were between 75.8–80.3°C, 422–514, 180–311, 134–212, 400–439 and 102–151 Rapid Visco Units (RVU), respectively. Turbidity values of gelatinized starch pastes increased during refrigerated storage. The relationships between different properties were also determined using Pearson correlation coefficients. Amylose content showed a positive correlation with swelling power, turbidity and granule diameter. Swelling power showed a negative correlation with solubility and setback. To, Tp and Tc showed positive correlation with turbidity, pasting temperature and were negatively correlated to peak and breakdown viscosity.  相似文献   
992.
Carbohydrates are the major storage reserves in seeds, and they are produced and accumulated in specific tissues during the growth and development of a plant. The storage products are hydrolyzed into a mobile form, and they are then translocated to the developing tissue following seed germination, thereby ensuring new plant formation and seedling vigor. The utilization of seed reserves is an important characteristic of seed quality. This review focuses on the seed storage reserve composition, source–sink relations and partitioning of the major transported carbohydrate form, i.e., sucrose, into different reserves through sucrolytic processes, biosynthetic pathways, interchanging levels during mobilization and crosstalk based on vital biochemical pathways that interlink the carbon and nitrogen cycles. Seed storage reserves are important due to their nutritional value; therefore, novel approaches to augmenting the targeted storage reserve are also discussed.  相似文献   
993.
To introduce functional moieties to Tefzel film, a copolymer of tetrafluoroethylene and ethylene, graft copolymerization of vinyl monomers such as acrylonitrile (AN) and methacrylonitrile (MAN) was attempted by a preirradiation method in aqueous medium. Optimum conditions for obtaining the maximum percentage of grafting have been evaluated for both monomers. Maximum grafting of AN (52.2%) and MAN (77.7%) is obtained at a total dose of 3.14 and 2.69 × 104 Gy, respectively, using [AN] = 3.018 mol/L and [MAN] = 1.177 mol/L in 10 mL of water. The effect of aliphatic alcohols of varying chain length, such as methanol, ethanol, isopropanol, n‐butanol, and cyclohexanol, on percentage add‐on of AN and MAN has also been studied. It has been found that all the alcohols decreased the percentage of grafting. Characterization of Tefzel and grafted Tefzel films has been carried out by IR spectroscopy and thermogravimetric analysis. Grafted Tefzel film has been found to have improved thermal resistance. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1171–1178, 2000  相似文献   
994.
Preirradiated isotactic polypropylene (IPP) powder has been modified by grafting 2-vinyl pyridine (2-VP) and styrene (Sty) in an aqueous medium. The graft copolymerization reaction was studied under different experimental conditions such as total dose, monomer concentration, amount of the solvent, time of reaction and temperature to determine the optimum conditions for affording maximum percentage of grafting (Pg). Maximum grafting percent of 2-VP (180%) and styrene (117%) was obtained under optimum conditions. The rate of grafting (Rg) of 2-VP and styrene has also been determined as a function of total dose, initial monomer concentration and the reaction temperature. From maximum Pg and different Rg values of 2-VP and Sty, 2-VP is more reactive towards grafting as compared to styrene under optimum conditions. Characterization of the graft copolymers is based on differential scanning calorimetric (DSC) analysis. Isolation of the grafted poly(2-VP) and poly(styrene) chains from the grafted samples provides an additional evidence of formation of the graft copolymer.  相似文献   
995.
Ginger juice and paste (from 2 to 8%, ginger candy from 5 to 20%, and ginger powder from 0.5 to 2%) were incorporated into the ice cream mix prior to freezing. Inclusion of the juice and paste reduced total solids, fat, protein and overrun, and increased antioxidant activity and phenols, whereas the ginger candy and powder increased solids, crude fibre, antioxidant activity and phenols, and diminished fat and overrun. Acidity increased with the ginger juice and powder, whereas it decreased with the ginger paste and candy. First dripping time amplified and melting rate declined with all the ginger preparations. Ice cream containing ginger juice, paste, candy and powder at 6, 4, 10 and 1%, respectively, achieved the highest overall acceptability scores.  相似文献   
996.
Nanocrystalline molybdenum disilicide (MoSi2) is synthesized in a specially designed autoclave at 900°C. The XRD results revealed that the formation of MoSi2 is favorable with the blend of MoO3, Si, and Mg powders. The HR-TEM and SAED patterns confirm the formation of MoSi2 phase. The structural parameters (crystallite size, strain, stress, and deformation energy density) are calculated using the Williamson-Hall (W-H) analysis. The formation mechanism involved in the synthesis of MoSi2 is proposed. The nonisothermal oxidation kinetics (~1200°C) of MoSi2 phase is examined through the thermal analysis techniques. The activation energy is determined by the Kissinger-Akahira-Sunsose isoconversional kinetic model. Finally, the reaction mechanism involved during the oxidation of MoSi2 phase is identified using the integral master-plots method.  相似文献   
997.
Neural Computing and Applications - Segmentation of biomedical images is the method of semiautomatic and automatic detection of boundaries within 2D and 3D images. The major challenge of medical...  相似文献   
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