The effects of soaking of whole, dehulled and ground millet and soybean seeds on phytate degradation and Phy/Fe and Phy/Zn molar ratios

The degradation and leaching of phytates, phytase activity and iron and zinc concentrations have been studied after soaking of whole seeds, dehulled seeds and flours of millet and soybean, in order to investigate the efficiency of soaking on reducing Phy/Fe and Phy/Zn molar ratios. When using millet grains, dehulling and milling before soaking facilitated the leaching of phytates and phytases in the aqueous medium and hence phytate degradation. Dehulling of soybean seeds led to a marked increase in phytate content, whereas milling favoured reactions between phytases and phytates. The Phy/Fe and Phy/Zn molar ratios decreased only slightly during soaking. The highest decreases for millet were obtained after soaking of flour for 8 h (Phy/Fe: 10.8–7.7 and Phy/Zn: 20.3–15.1), and after soaking of whole seeds for 24 h for soybean (Phy/Fe: 10.4–9.4 and Phy/Zn: 23.8–19.1). Cooking of flours with water used for soaking did not increase phytate degradation.     

渗透脱水蓝莓流化床干燥工艺的研究

经渗透脱水处理的蓝莓在流化床中用5种不同的干燥温度(50、60、70、80、90℃)进行干燥,结果显示, 干燥温度影响物料的水分散失,水分散失率随温度的提高而增加。随着干燥处理的进行水分含量和水分活度都呈下降趋势,且温度越高,两者下降越多。根据费克第二不稳定扩散法则,计算出不同温度下的有效水分扩散率 (D_(eff))分别为(0．753 2～3．673 7)×10~(-10)m~2/s。在干燥脱水处理过程中 D_(eff)随处理温度升高而增加。     

非相态稀体系三元复合驱油机理数学模型

在引进的UTCHEM数值模拟软件基础上，建立了非相态稀体系三元复合驱油机理数学模型，并利用所建立的数学模型对UTCHEM数值模拟软件进行了改进，对改进后的模型进行的模拟功能测试结果表明，模拟计算给出的水驱，聚合物驱和三元复合驱综合含水率变化曲线符号实际开采规律；三元复合驱比聚合物驱较大幅度地降低了油层剩余油饱和度，说明所建立的非相态稀体系驱油机理数学模型能够正确地模拟三元复合驱过程。     

An analysis of students’ spontaneous computer-mediated help seeking: A step toward the design of ecologically valid supporting tools

This study analyzes middle school students’ spontaneous mathematics-related help-seeking behavior, in view of making ecologically valid recommendations for the design of supporting tools or “help systems”. Our aim was to investigate the content of students’ help-seeking messages – Are there different forms of help-seeking messages and do they evolve with age? We used the archives of a French forum that provides students with free individualized help in mathematics. The data consisted of 206 messages sent by French middle school students over a period of 42 months. The constituent categories of the messages were identified. The results showed that not all middle school students use the same help-seeking “format”. Compared to sixth graders, ninth graders wrote messages containing more constituent categories, i.e., they provided the online expert with more kinds of information. A detailed analysis of the categories further showed that older students’ messages more often contained explicit help requests and contextual information than did younger students’ messages. Thus, the messages of the oldest students (age 15) were both cognitively more understandable and socially more acceptable than those of the youngest students (age 11). The interpretation of these findings and their implications for designing help systems are discussed.     

Highly active Cu-ZnO catalysts for the WGS reaction at medium–high space velocities: Effect of the support composition

Cu-ZnO based catalysts are the benchmark materials for the low-temperature WGS reaction. However, they present a crucial drawback which limits their application in portable devices: they only work under very low space velocities. In this study, we have developed a series of multicomponent Cu-ZnO catalysts able to work at relatively high space velocities with outstanding activity and stability. Different reference supports have been utilised with CeO₂-Al₂O₃ being the most promising system. Overall, this work describes a strategy to design advanced Cu-based catalysts that can overcome the residence time restrictions in the WGS reaction.     

Psychological predictors of college students’ cell phone use while driving

Despite the known risk, many people talk on a phone while driving. This study explored psychological predictors of cell phone use while driving. College students (final N = 69) completed a survey and predicted their driving performance both with and without a simultaneous phone conversation. Their actual performance on a driving simulator was then assessed. Cell phone use reduced performance on the simulation task. Further, perceiving oneself as good at compensating for driving distractions, overestimating one's performance on the driving simulator, and high illusory control predicted more frequent cell phone use while driving in everyday life. Finally, those who talked more frequently on a phone while driving had poorer real-world driving records. These findings suggest illusory control and positive illusions partly explain driver's decisions of whether to use cell phones while driving.     

A representative and comprehensive review of the electrical and thermal properties of polymer composites with carbon nanotube and other nanoparticle fillers

In this review we present the results of our literature investigation into the electrical and thermal properties of carbon nanotube polymer composites. A short selection of data relating to conductive polymer composites with various fillers is provided for comparison. The effects of filler properties such as type and size, the use of hybrid fillers, fabrication methods for polymer composites and the importance of the modeling of the electronic and thermal transport mechanisms are discussed, as are more general factors influencing the properties of these composites. This review represents a comprehensive survey and constructive study and should serve as a useful reference tool for industrial and academic researchers working in this field. © 2017 Society of Chemical Industry     

Effect of dehydroxylation on the specific heat of simple clay mixtures

Specific heats of four clays (standard reference kaolins, commercial kaolin and montmorillonite) before and after dehydroxylation have been measured. The results were compared with handbook data for the thermal chemical properties of solids. Good agreement has been obtained for the reference kaolin before any thermal treatment. Then, following thermal treatments at 500 °C, 600 °C and 700 °C, dehydroxylation leads to a progressive decrease of heat capacity per unit mass. After dehydroxylation, heat capacity values for all the studied materials are rather similar and agree closely with those estimated by the rule of mixtures. Finally, an empirical relation describing the specific heat capacity (C) in J kg⁻¹ K⁻¹ of dehydroxylated kaolin from 40 °C to 1100 °C is proposed: C = 1128 + 0.102T − 36 × 10⁶T⁻² where T is in K.     

Verschleißeigenschaften salzbadnitrocarburierter Oberflächen verschiedener Badvarianten

This paper explores the influence of two types of bath variants (Tenifer Classic and Tenifer Low Porosity) for the liquid nitrocarburising treatment technology on different types of steel (34CrAINi7, 42CrMoS4, 40CrMnNiMo, X8CrNiS18–9, EN-GJS-600 and especially 16MnCrS5, two 16MnCrS5-type steels and EN-GJS-400) with special focus on their tribological behaviour under dry conditions. A cylinder-on-plate test rig (Optimol SRV4) was employed to investigate the wear resistance of the treated materials. As one result it could be shown, that better wear resistivity under dry conditions not subsequently means harder and denser white layer.     

A survey of Irish fruit and vegetable waste and by-products as a source of polyphenolic antioxidants

In this study, fruit and vegetable by-product and waste sources in Ireland were tested for their antioxidant activity and polyphenol content. The highest levels of antioxidants measured by both ferric reducing antioxidant power (FRAP) and diphenyl-picrylhydrazyl (DPPH) assays, were detected in whole kiwifruit. Of the vegetable by-products, broccoli stems showed the best antioxidant potential. The level of polyphenols as assessed by the Folin–Ciocalteu Reagent (FCR) was significantly correlated with the level of polyphenols by HPLC–DAD (r = 0.93). The level of polyphenols assessed by HPLC–DAD was not significantly correlated with the antioxidant assays. Apple pomace and vegetable by-products were found to be good sources of both polyphenols and antioxidants and due to their abundance may be exploitable resources to use as food ingredients.