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1.
《International Dairy Journal》2006,16(3):268-273
Buffalo milk proteins (casein, co-precipitate or whey protein concentrate) were phosphorylated with phosphorus oxychloride (POCl3) at three different pH values (5.0, 7.0 and 9.0). The solubilities of phosphorylated milk proteins were examined over the pH range 3.0–9.0 in water and ionic (0.1 m NaCl or 10–70 mm Ca2+) systems. The solubilities of buffalo milk proteins decreased at pH 3.0, while there was an increase in the solubilities of casein and co-precipitate near their isoelectric points upon phosphorylation. Solubilities of these phosphorylated milk proteins were pH dependent in 0.1 m NaCl but there was a decrease in their solubilities with increase in calcium ion concentration. This alteration could be due to the shifting of isoionic points of phosphorylated buffalo milk proteins towards acidic pH. 相似文献
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《Journal of the European Ceramic Society》2005,25(6):857-862
Compressive creep tests in air were carried out on 1 cat.% Fe-doped alumina at a temperature T=1400 °C. Iron doping affected the plastic deformation by different ways in relation with Fe2+ cations population. Fe2+ cations sped up the deformation rates. FeAl2O4 spinel precipitates were identified and they were found (i) to interact with alumina grain boundaries (ii) to limit the grain growth within a range of strain. The Fe2+ cations underwent oxidation and this resulted in the dissolution of the some precipitates and in the decrease of deformation rates. It was suggested that deformation sped up this evolution through mass transport and that time was not a dominating parameter. 相似文献
4.
《Sensors and actuators. B, Chemical》2006,113(1):106-111
A stable film made from hydroxyethylcellulose (HEC) on pyrolytic graphite (PG) electrode was employed for incorporating hemoglobin (Hb), myoglobin (Mb) and horseradish peroxidase (HRP), and the electrochemical characteristics of the proteins were studied correspondingly. Experimental results revealed that HEC film could greatly accelerate electron transfer between the proteins and electrode, and the proteins showed a thin layer electrochemical behavior in the film. Moreover, all the proteins in the film exhibited good catalytic activity towards the reduction of hydrogen peroxide (H2O2) in the low H2O2 concentration range. In the high concentration range, H2O2 would exhibit toxicity effect on the proteins. The electrochemical properties and electrocatalytic abilities of the three heme proteins in HEC film have been compared, and the optimal conditions for H2O2 biosensor fabrication have been obtained. 相似文献
5.
《Food Control》2007,18(2):93-101
The antimicrobial properties of pure phenolic compounds and polyphenols of different wines against pathogens were investigated. It was observed that bacterial species exhibited different sensitivities towards the different concentrations of phenolic compounds. Escherichia coli was the most sensitive bacterium and Flavobacterium sp. was resistant against all phenolic compounds tested. All wine samples showed antimicrobial properties and the inhibition increased when the polyphenols concentration of wines increased. Clarified wines were inactive against all bacteria, indicating that polyphenolic compounds present in red wines, are responsible for the antimicrobial effects observed. The different concentrations of polyphenols in wines could have an important impact on consumers with the consequent increase in wine commercialization. 相似文献
6.
Emad Karrar Isam A. Mohamed Ahmed Muhammad Faisal Manzoor Frederick Sarpong Wei Wei Xingguo Wang 《European Journal of Lipid Science and Technology》2021,123(3):2000104
Cucurbitaceae family seeds are mostly discarded as agro-industrial wastes. Gurum (Citrullus lanatus var. colocynthoide) is an underutilized wild cucurbit plant, closely related to desert watermelon, which is grown abundantly in some African countries. Gurum seeds can play a significant role in health and nutrition due to their high oil content. This review describes the nutritional composition of gurum seeds and their oil profile. Gurum seeds are a good source of oil (27–35.5%), fiber (26–31%), crude protein (15–18%), and carbohydrates (14–17%). Gurum seeds oil is extracted by supercritical CO2 (SFE), screw press, and solvent extraction techniques. The gurum seeds oil is composed of unsaturated fatty acids with a high proportion of linoleic acid (C18:2) and oleic acid (C18:1). Gurum seeds oil contains various bioactive compounds, such as tocopherols, phytosterols, and polyphenols. It is reported that solvent extraction gives a higher yield than the screw press and SFE, but the SFE is preferred due to safety issues. More studies are required for producing better quality gurum seeds oil by using novel extraction techniques that can increase oil yield. 相似文献
7.
《Fuel Processing Technology》2005,86(10):1087-1096
Semirefined and refined vegetable oils are the predominant feedstocks for the production of biodiesel. However, their relatively high costs render the resulting fuels unable to compete with petroleum-derived fuel. We have investigated the production of fatty acid methyl esters (FAME; biodiesel) from soapstock (SS), a byproduct of edible oil refining that is substantially less expensive than edible-grade refined oils. Multiple approaches were taken in search of a route to the production of fatty acid methyl esters from soybean soapstock. The most effective method involved the complete saponification of the soapstock followed by acidulation using methods similar to those presently employed in industry. This resulted in an acid oil with a free fatty acid (FFA) content greater than 90%. These fatty acids were efficiently converted to methyl esters by acid-catalyzed esterification. The fatty acid composition of the resulting ester product reflected that of soy soapstock and was largely similar to that of soybean oil. Following a simple washing protocol, this preparation met the established specifications for biodiesel of the American Society for Testing and Materials. Engine emissions and performance during operation on soy soapstock biodiesel were comparable to those on biodiesel from soy oil. An economic analysis suggested that the production cost of soapstock biodiesel would be approximately US$ 0.41/l, a 25% reduction relative to the estimated cost of biodiesel produced from soy oil. 相似文献
8.
Selection of strategies that help reduce riverine inputs requires numerical models that accurately quantify hydrologic processes. While numerous models exist, information on how to evaluate and select the most robust models is limited. Toward this end, we developed a comprehensive approach that helps evaluate watershed models in their ability to simulate flow regimes critical to downstream ecosystem services. We demonstrated the method using the Soil and Water Assessment Tool (SWAT), the Hydrological Simulation Program–FORTRAN (HSPF) model, and Distributed Large Basin Runoff Model (DLBRM) applied to the Maumee River Basin (USA). The approach helped in identifying that each model simulated flows within acceptable ranges. However, each was limited in its ability to simulate flows triggered by extreme weather events, owing to algorithms not being optimized for such events and mismatched physiographic watershed conditions. Ultimately, we found HSPF to best predict river flow, whereas SWAT offered the most flexibility for evaluating agricultural management practices. 相似文献
9.
Min-Hyun?Lee Ju-Hyun?Lee Hyun-Mi?Kim Young-Rok?Kim Tae-Joon?Jeon Y.?Eugene Pak Ki-Bum?KimEmail author 《Microfluidics and nanofluidics》2014,16(1-2):123-130
We have measured leakage current in a silicon substrate-based nanopore membrane device immersed in an aqueous environment which typically shows the current level of few nA. This current level is compared with the measured current density (400 nA/cm2 at 1 V) from the pristine Si wafer (p-type, 1016/cm3 boron doping) indicating that the exposed Si surface in a nanopore membrane device acts as an electrochemical reaction site. The leakage current is drastically reduced from >10 nA to <100 pA at 1 V by the deposition of a dielectric layer to the Si-based nanopore membrane device. We also noted that the root-mean-square noise of the ionic current is also reduced from 38 to 28 pA in correlation with the reduction of leakage current, indicating that electrochemical reaction provides one of the major sources of noise. 相似文献
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