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41.
Natural dyes find use in the coloring of textiles, drugs, cosmetics, etc. Owing to their nontoxic effects, they are also used for coloring various food products. In the present study antimicrobial properties of 8 food dyes against 10 bacteria and 5 fungal organisms were investigated. It was observed that red dyes showed best antibacterial activity while yellow dyes showed better antifungal activity. Dyes obtained from catechu (Acacia catechu) and myrobalan (Terminalia chebula) is not sufficiently effective against the tested microorganisms. In addition to antimicrobial analysis, antioxidant activity by 3 different methods was also investigated. In all the methods, red dye was found to have greater antioxidant activity. It suggest that the addition of these dyes in food not only enhances the value addition by making the food more presentable but also shall address the issue of food supplementation with substances that are good antibiotics and antioxidants, subsequently proving to be health benefactors.  相似文献   
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In continuation of our previous work on phase diagram investigations of alkali metal-alkaline earth metal-uranium oxides, the sub-solidus phase relations in K-Sr-U-O quaternary system were determined at 850 °C in air. A pseudo-ternary phase diagram of UO3-SrO-K2O was drawn using reported ternary compounds in K2O-UO3 and SrO-UO3 systems, a single quaternary compound, K8Sr2U6O24 and various phase mixtures. These compounds and mixtures were synthesized by solid route, by heating K2CO3, SrCO3 and UO3 in different molar proportions at 850 °C. The phase fields of K2O-SrO-UO3 pseudo-ternary phase diagram were established by X-ray powder diffraction analysis. Gibbs energies of formation of binary and ternary uranates were estimated. The Gibbs energies of formations of A8Sr2U6O24 (A = Na/K/Rb/Cs) type compounds for different alkali metals were compared to find a reason for the stability of the compound for sodium, potassium and rubidium and its instability for cesium.  相似文献   
44.
Graphs of pairwise incidences between collections of rigid bodies occur in many practical applications and give rise to large algebraic systems for which all solutions have to be found. Such pairwise incidences have explicit, simple and rational parametrizations that, in principle, allow us to partially resolve these systems and arrive at a reduced, parametrized system in terms of the rational parameters. However, the choice of incidences and the partial order of incidence resolution strongly determine the algebraic complexity of the reduced, parametrized system—measured primarily in the number of variables and secondarily in the degree of the equations.  相似文献   
45.
Although tumor-antigen-based therapeutic cancer vaccines are a potential cancer immunotherapy strategy, recent clinical trials show low efficacy for multiple reasons. One method that has been recently investigated to improve the efficacy of therapeutic cancer vaccines is the development of implantable vaccines for sustained delivery of antigens and CD8 T cell activation. Here, we optimized the composition for an implantable vaccine scaffold composed of alginate, polyvinyl alcohol, and poly(methyl vinyl ether- alt-maleic anhydride) loaded with tumor antigens. Considering the adjuvant property of aluminum compounds, aluminum ion was used to crosslink alginate in the scaffold. The scaffold showed an effective antigen incorporation efficiency of 90.34 ± 0.55% using ovalbumin as the model antigen and 89.67 ± 2.8% using B16-F10 cell lysate. SEM analysis of the scaffold showed pore size ranging from 5 to 10 μm. Cell viability analysis using mouse RAW 264.7 macrophages proved the cytocompatibility of the scaffold. In vitro antigen release studies using ovalbumin showed 8.42% release for a period of 14 days. In vivo antitumor analysis carried out in subcutaneous mouse B16-F10 melanoma model demonstrated that the scaffold vaccine reduced the rate of tumor growth and improved survival in tested animals. The median survival time increased from 29 days in untreated animals to 58 days in scaffold vaccine-implanted animals.  相似文献   
46.
This work reports on a study of batch extraction of metal ions (copper and zinc) from dilute aqueous solutions as well as recovery of copper from electroplating waste water by the emulsion liquid membrane (ELM) technique. Several experiments were conducted to assess the effect of membrane composition on metal recovery. The effect of surfactant concentration, carrier concentration, and emulsification time on the emulsion stability has been reported. The velocity profile and flow model of the two‐phase mixing system during the preparation of the emulsion was generated using computational fluid dynamics (CFD). The batch extraction was carried out under various experimental conditions, such as agitation speed, M/E ratio, solute concentration in the feed phase, and carrier concentration in the membrane phase on the percentage recovery of zinc and copper ions in their respective feed streams. The operating parameters were optimized for maximum recovery. A comparison on the percentage recovery was made between synthetic solution and electroplating effluent containing copper ions.  相似文献   
47.
以臭氧为活化剂,炭化的米糠为原料制备出活性炭。采用氮吸附、SEM-EDAX和FT-IR对样品进行表征。活性炭的比表面积由活化前的20 m2/g增加到380 m2/g。在臭氧活化过程中,吸附在炭材料上的二氧化硅变疏松,从而导致碳逸出。臭氧同时以氧分子和原子形式存在于炭表面。氧原子,作为强氧化剂,将炭表面氧化成酸性官能团如羧基、酮基和酚基。采用该活性炭吸附Cr(VI)离子,Cr(VI)离子的最大去除率(94%)的条件为:p H值2.0、浓度100 mg/L、吸附量0.2 g,时间2.5 h及转速300 r/min。采用吸附平衡和动力学模型探讨吸附机理,结果表明,吸附等温线符合Freundlich方程,吸附速率符合准二级动力学方程。吸附是自发的放热反应,可能与Na OH脱落而恢复Cr和碳有关。  相似文献   
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M.S. Meera  M.K. Bhashyam  S.Z. Ali 《LWT》2011,44(10):2199-2204
Sorghum flour is susceptible to rancidity and develops off-flavor within a short duration when stored. Heat treatment on the development of rancidity after long-term storage of flour was studied. Heat treatment varying in severity was applied to the whole grains of different varieties of sorghum viz., CSH-9, CSH-5, M35-1 and a local variety varying in their morphological features. A trend was seen that when the thermal duration was for a shorter time, the shorter was the storage duration in certain varieties. Exposure of grains to moist heat for 15 min retarded hydrolytic rancidity significantly (p < 0.05) in CSH-5 until 6 months of storage and in the remaining varieties until 8 months of storage, Heat application for 15 min retarded the development of rancidity irrespective of the morphological variations and the oil content. Lipase activity varied among the varieties with CSH-5 recording higher activity when compared to the other varieties. No major differences in the physicochemical properties were observed in flours from 15 min heat-processed grains when compared to flours from unprocessed grains.  相似文献   
50.

Weather describes the condition of our atmosphere during a specific period of time, and climate represents a composite of day to day weather over longer period of time. Climatology attempts to analyze and explain the impact of climate so that the society can plan accordingly. Climatology analysis is often done on radar images representing various climatic conditions. These images contain varying scale of severity for any specific climatic parameter of study. The climatologists often find it convenient to analyze climatic conditions if tools are available to segment the weather images based on the severity scale which is represented by different colors. Segmentation of the weather radar image is also used for automated analysis of weather conditions. Differential evolution (DE) approach instead is used for fast selection of optimal threshold. In present paper, we have applied DE with multilevel thresholding for weather image segmentation which results in minimum computational time and excellent image quality. A new mutation strategy for DE named reconstructed differential evolution (RDE) strategy is suggested for better performance over image segmentation. Using fuzzy entropy and RDE for multilevel thresholding provides better results in comparison with last suggested methods.

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