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171.
Polypeptide profile and functional properties of defatted meals and protein isolates of canola seeds
Laboratory‐defatted meals from four types of canola seeds were analysed for protein profile by reducing and non‐reducing forms of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE). In the absence of a reducing agent (2‐mercaptoethanol), four major polypeptide bands (16, 18, 30 and 53 kDa) were prominent in similar ratios in all varieties. In the presence of mercaptoethanol, significant reductions in intensity of the major bands occurred, suggesting that the major polypeptides contained smaller units which were held together by disulphide bonds. Meals from Brassica napus seeds had higher protein solubilities than meals from Brassica rapa seeds. Meals with higher protein solubility values also had higher foaming capacity (FC) values. Generally, the acid‐precipitated (pH 4.0) protein isolates (APPIs) had higher FC values than the calcium‐precipitated isolates (CPPIs). On the other hand, the CPPIs formed emulsions with higher values of emulsifying activity index (EAI) when compared to the APPIs. The results indicate that variations in functional properties of protein isolates and meals between the four seed types were probably due to differences in protein conformation in aqueous solutions rather than differences in polypeptide composition. © 2001 Society of Chemical Industry 相似文献
172.
This paper presents a capacity planning model for the Indian aluminium industry based on a linear dynamic programming technique. The model has been used to analyse energy demand and CO2 emission for the period 1992–2021. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
173.
An attempt to estimate CO2 emissions from the cement industry in India has been made. The impact of variations in product mixes and technology on CO2 emissions have also been analysed on the basis of four different scenarios. © 1997 by John Wiley & Sons, Ltd. 相似文献
174.
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176.
We consider the suitability of the Java concurrent constructs for writing high-performance SPMD code for parallel machines. More specifically, we investigate implementing a financial application in Java on a distributed-memory parallel machine. Despite the fact that Java was not expressly targeted to such applications and architectures per se, we conclude that efficient implementations are feasible. Finally, we propose a library of Java methods to facilitate SPMD programming. © 1997 John Wiley & Sons, Ltd. 相似文献
177.
In this work, the influence of pure Al (Ti6Al) and V (Ti4?V) powder additions on the sintering behaviour of a coarse CP-Ti powder compact was investigated. Pure Al melts and spreads to form intermetallic layers at the CP-Ti surface, causing swelling and prevention of sintering and shrinkage below 1050°C. Ti4?V compacts do not swell and begin to sinter at 990°C. The sinter rate for both Ti4?V and Ti6Al are similar at 1200°C and higher than the CP-Ti compact alone. Aluminium melting distributes this element better than the dispersed V particles, leading to more rapid homogenisation. When both pure Al and V are present (Ti6Al4?V), the sintering rate at 1200°C is similar to that of Ti6Al and Ti4?V. However, swelling is increased and homogenisation is slower, resulting in a reduced sintering aid effect compared to Ti6Al and Ti4?V. 相似文献
178.
Maria Buffini Séverine Goscinny Joris Van Loco Anne P. Nugent Janette Walton Albert Flynn 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(3):425-438
This research investigated the intakes of six intense sweeteners: acesulfame-K (E950), aspartame (E951), cyclamate (E952), saccharin (E954), sucralose (E955), and steviol glycosides (E960) in the diets of Irish adults, using data from the National Adult Nutrition Survey. A food label survey that included products currently available on the Irish market supplemented the analysis. Sweetener intakes were investigated using three different exposure scenarios; beginning with a crude assessment which assumed that all foods permitted to contain the additives of interest always did contain them, and at their maximum permitted level (Tier 1). Refined assessments estimated intakes of the six sweeteners using food consumption data up to brand level with additive occurrence data from a survey of products currently available on the Irish market (Tier 2) and sweetener concentration data (Tier 3). Results of all exposure assessment scenarios demonstrate that intakes of each of the sweeteners of interest by the total population were below the relevant ADI level (mg kg?1 bodyweight?1), even by high consumers (P99). The three sweeteners consumed in highest amounts were acesulfame-k, aspartame, and sucralose. The main sources of these sweeteners in the diet were ‘cider and perry’, ‘energy reduced and no added sugar (ER and NAS) carbonated flavoured drinks’, ‘table-top sweeteners’, ‘dairy products’, ‘solid food supplements’, and ‘sauces’. Intakes of the six intense sweeteners are currently not a concern among Irish adults. However, exposure to these chemicals should be monitored on a regular basis due to evolving market and consumption patterns. 相似文献
179.
Junling Shi Zhongli Pan Tara H. McHugh Edward Hirschberg 《Food and Bioprocess Technology》2009,2(3):271-278
In order to obtain optimal processing conditions for producing infused blueberries with high solid gain, we investigated the
infusion characteristics of blueberries under various processing parameters in sugar solutions with 1:1 ratio of solution
and berries. Static batch constant concentration infusion and dynamic batch infusion (DBI) were tested as the alternative
operations for the traditional static batch infusion. The studied parameters were solution temperature (25 to 70 °C), concentration
(20 to 70°Brix), and types of osmotic agent (fructose, dextrose, polydextrose, sucrose, maltodextrin, and corn syrup). The
results showed that high solid gain can be achieved by maintaining high and constant concentration of infusion solution at
high temperature with dynamic infusion. For DBI, high temperature and high solution concentration resulted in fast and high
solid gain. The rate of water loss increased with an increase in solution temperature and concentration. To obtain high quality
sugar-infused products with high product yield, a DBI process of 50 °C and 50°Brix sugar infusion is recommended, which could
have solid gain of 1.65 g/g after a 5-h infusion. Polydextrose showed higher solid gain than sucrose when infusion time was
longer than 180 min, although it had lower solid gain in short-term infusion. 相似文献
180.
The fate of Zn and other sorbed heavy metals during microbial reduction of iron oxides is different when comparing synthetic Fe-(hydr)oxides and natural sediments undergoing a similar degree of iron reduction. Batch experiments with the iron-reducing organism Shewanella putrefaciens were conducted to examine the effects of an aqueous complexant (nitrilotriacetic acid or NTA), two solid-phase complexants (kaolinite and montmorillonite), an electron carrier (anthraquinone disulfonic acid or AQDS), and a humic acid on the speciation of Zn during microbial reduction of synthetic goethite. Compared to systems containing only goethite and Zn, microbial Fe(III) reduction in the presence of clay resulted in up to a 50% reduction in Zn immobilization (insoluble in a 2 h 0.5 M HCl extraction) without affecting Fe(II) production. NTA (3 mM) increased Fe(II) production 2-fold and resulted in recovery of nearly 75% of Zn in the aqueous fraction. AQDS (50 microM) resulted in a 12.5% decrease in Fe(II) production and a 44% reduction in Zn immobilization. Humic acid additions resulted in up to a 25% decrease in Fe(II) production and 51% decrease in Zn immobilization. The results suggest that all the components examined here as either complexing agents or electron shuttles reduce the degree of Zn immobilization by limiting the availability of Zn for incorporation into newly formed biogenic minerals. These results have implications for the remediation of heavy metals in a variety of natural sediments. 相似文献