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91.
The effect of carbonation on physical and functional properties of egg white powder during spray drying and storage under vacuum, air, and CO2 gas was investigated. Carbonation (2,000?mg/kg) of fresh egg white before spray drying was found to improve the foaming properties of the fresh egg white powder. However, the carbonation caused accelerated changes in color, solubility, and foaming properties of the powder during storage. In addition, the results showed greater changes in the color and decreased solubility in the powder samples stored in impermeable hermetically sealed bags under CO2 and vacuum conditions than in normal air.  相似文献   
92.
Halfwave retarder for all polarization states   总被引:1,自引:0,他引:1  
Bhandari R 《Applied optics》1997,36(13):2799-2801
We show that a device consisting of an optical rotator placed between two identically oriented quarter-wave plates always acts as a halfwave retarder for some pair of orthogonal elliptically polarized states that can be selected by linear adjustment of the optical rotation and orientation of the quarter-wave plates.  相似文献   
93.
Neural Computing and Applications - Image segmentation using multilevel thresholding (MT) is one of the leading methods. Although, as most techniques are based on the image histogram to be...  相似文献   
94.
Growth curve models are routinely used in various fields such as biology, ecology, demography, population dynamics, finance, econometrics, etc. to study the growth pattern of different populations and the variables linked with them. Many different kinds of growth patterns have been used in the literature to model the different types of realistic growth mechanisms. It is generally a matter of substantial benefit to the data analyst to have a reasonable idea of the nature of the growth pattern under study. As a result, goodness-of-fit tests for standard growth models are often of considerable practical value. In this paper we develop some natural goodness-of-fit tests based on finite differences of the size variables under consideration. The method is general in that it is not limited to specific parametric forms underlying the hypothesized model so long as an appropriate finite difference of some function of the size variables can be made to vanish. In addition it allows the testing process to be carried out under a set up which manages to relax most of the assumptions made by Bhattacharya et al. (2009); these assumptions are generally reasonable but not guaranteed to hold universally. Thus our proposed method has a very wide scope of application. The performance of the theory developed is illustrated numerically through several sets of real data and through simulations.  相似文献   
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Different nanostructured polyaniline (PAni) has been synthesized via facile template‐free electrochemical synthesis approach in aqueous medium. Instead of conventionally used aniline, aniline sulphate was used in electrochemical polymerization. The synthesis process involves simultaneous doping with combination of inorganic and organic acid, i.e., sulfuric acid (H2SO4) and p‐toluenesulfonic acid (PTSA) at different ratios keeping total dopant concentration constant. Synergistic increase in conductivity is observed and the best conductivity is achieved at 3:1 ratio of [H2SO4]:[PTSA]. Different nanostructures of PAni are revealed through morphological analysis consisting of nanosphere, nanorod, and clustered particles among which finer nanorods show the best electrical conductivity. Upon controlled heat treatment followed by further cooling, resistivity increases, but after one day it decreases again and in the optimized dual doped PAni, it approaches approximately the same value of initial resistance. Lattice strain and benzenoid to quinonoid ratio increases with heat treatment. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
98.
Research on the stability of flavours during high temperature extrusion cooking is reviewed. The important factors that affect flavour and aroma retention during the process of extrusion are illustrated. A substantial number of flavour volatiles which are incorporated prior to extrusion are normally lost during expansion, this is because of steam distillation. Therefore, a general practice has been to introduce a flavour mix after the extrusion process. This extra operation requires a binding agent (normally oil), and may also result in a non-uniform distribution of the flavour and low oxidative stability of the flavours exposed on the surface. Therefore, the importance of encapsulated flavours, particularly the β-cyclodextrin-flavour complex, is highlighted in this paper.  相似文献   
99.
Communication security with quantum key distribution has been one of the important features of quantum information theory. A novel concept of secured direct communication with no need of establishing any shared secret key has been the next step forward. The present paper presents a secured communication scheme with three particle GHZ state as the initial state where the receiver can simultaneously receive information from two parties. Possible eavesdropping has been examined.   相似文献   
100.
The effects of dilution of protein content in skim milk (34–8.5% protein content), by lactose addition, on the surface composition, water sorption property and glass transition temperatures of spray-dried powders were investigated. The X-ray photoelectron spectroscopy (XPS) study of spray-dried powders showed preferential migration of proteins toward the surface of the milk particles whereas the lactose remained in the bulk. Sorption studies showed that the lower protein concentration in milk powders is linked to an increased water adsorption property and lowering of water activity (aw) for lactose crystallization. Analysis of glass transition temperature (Tg) of the powders sorbed at different humidities showed no distinct change in Tg values, indicating the dominant effect of lactose on the glass transition temperature of all the powders.  相似文献   
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