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Magdalena Zielińska-Dawidziak Dorota Piasecka-Kwiatkowska Jerzy R. Warchalewski Agnieszka Makowska Magdalena Gawlak Jan Nawrot 《European Food Research and Technology》2014,238(5):829-835
Grains of winter wheat (Korweta variety) were partially germinated in an abiotic stress condition (0–15 mM FeSO4 solutions) in order to accumulate iron by ferritin overexpression. The physical, chemical, biochemical properties and technological parameters of the obtained material as well as their resistance to an insect storage pest—granary weevil—were analyzed. Sprouted wheat grains with overexpression of ferritin contain 52 times more iron, more than 50 % in form of ferritin. The contents of reducing sugars, crude protein, fiber and ash as well as amylolytic activity increased significantly in sprouted wheat grain, while starch, fat, wet gluten, falling number and inhibition activity against granary weevil α-amylase decreased. Germinated wheat grain enriched with iron strongly affected granary weevil developmental parameters. Despite the fact that technological parameters of the product were deteriorated, it is worth to consider this material application as an iron supplement for cereal products, when the application of soybean is impossible. 相似文献
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Yoon H. Lee Takashi Kuboki Chul B. Park Mohini Sain Marianna Kontopoulou 《应用聚合物科学杂志》2010,118(1):452-461
In this study, nanosized clay particles were introduced into wood fiber/plastic composites (WPCs) to improve their mechanical properties and flame retardancy, which are especially important in various automotive and construction applications. A high degree of exfoliation for nanoclay in the wood fiber/high density polyethylene (HDPE) composites was successfully achieved with the aid of maleated HDPE (PE‐g‐MAn), through a melt blending masterbatch process. The structures and morphologies of the composites were determined using X‐ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. This article presents the effects of clay content and degree of clay dispersion on the mechanical and physical properties and flame retardancy of wood fiber/HDPE composites that contained a small amount of clay, in the range of 3–5 wt %. We concluded that achieving a higher degree of dispersion for the nanosized clay particles is critical to enhance the mechanical properties and the flame retardancy of WPCs when small amounts of clay are used. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
25.
Agnieszka?NowakEmail author Danuta?Kusewicz Halina?Kalinowska Marianna?Turkiewicz Piotr?Patelski 《European Food Research and Technology》2004,219(1):84-89
Correlation between H2S productivity (p) and sulfite reductase activity (A) was estimated for seven wine-producing yeasts. It was described by a linear function
p=f(A), the slope of which depended on the yeast strain. The most intensive H2S synthesis by all the examined yeasts was observed within the early logarithmic growth phase, either in nitrogen abundance and SO2 presence, or in nitrogen deficient and SO2-free medium. Sulfite reductase from all the strains was optimally active at pH close to 7.4. The enzyme from cryophilic yeasts displayed maximum activity at approximately 16 °C, and from mesophiles at 22–26 °C. The preparations showed different affinities toward sulfite (Km of 16.7–67.5 M). Values of activation energy in sulfite reduction depended on the yeast, and ranged from 14.07 to 67.04 kJ mol–1. 相似文献
26.
Bed and fly ashes originating from industrial-scale fluidized bed combustors (FBCs) were steam hydrated to produce sorbents suitable for further in situ desulphurization. Samples of the hydrated ash were characterized by X-ray diffraction analysis, scanning electron microscopy and porosimetry. Bed ashes were hydrated in a pressure bomb for 30 and 60 min at 200 °C and 250 °C. Fly ash was hydrated in an electrically heated tubular reactor for 10 and 60 min at 200 °C and 300 °C. The results were interpreted by considering the hydration process and the related development of accessible porosity suitable for resulphation. The performance of the reactivated bed ash as sulphur sorbent improved with a decrease of both the hydration temperature and time. For reactivated fly ash, more favourable porosimetric features were observed at longer treatment times and lower hydration temperatures. Finally, it was shown that an ashing treatment (at 850 °C for 20 min) promoted a speeding up of the hydration process and an increase in the accessible porosity. 相似文献
27.
Christopher J. Wilson Henny Volders Marianna Pantouvaki Alton B. Horsfall Zsolt T?kei 《Microelectronic Engineering》2010,87(3):398-401
An in situ study of self-forming barriers from a Cu-Mn alloy was performed to investigate the barrier growth using X-ray diffraction on damascene lines. The associated evolution in interconnect texture and Cu stress was also observed. The shift in Cu diffraction peak position was used to determine the change in Mn concentration and hence, estimate the thickness of the MnSixOy barrier. The observed peak shift followed a log(t) behaviour and is described well by metal oxidation kinetics, following the field enhanced diffusion model. We used multiple anneal temperatures to study the activation of the formation process, demonstrating a faster barrier formation with higher ion excitation. A strong [1 1 1] Cu texture was shown to develop during the anneal in contrast to traditional PVD barrier systems. Finally, the stress in the 100 nm Cu lines was calculated, observing a large in-plane relaxation when using a self-forming barrier due to reduced confinement. 相似文献
28.
Marianna N. Xanthopoulou Tzortzis Nomikos Elizabeth Fragopoulou Smaragdi Antonopoulou 《Food research international (Ottawa, Ont.)》2009,42(5-6):641-646
Pumpkin seeds have been implicated in providing health benefits. However their antioxidant or anti-inflammatory activity of their extracts has never been studied. Therefore, four commercially available pumpkin seeds were treated with two different extraction methodologies in order to obtain fractions with different content. The extracts were screened for their antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and for their inhibitory activity against lipid peroxidation catalyzed by soybean lipoxygenase.Most extracts tested have demonstrated radical scavenging activity, which depends on their total phenolic content, with fractions rich in phenolics showing the strongest activity. On the other hand, the phenolic content of extracts does not determine their activity against lipoxygenase, as acetone and polar lipid fractions are its strongest inhibitors. The presence of molecules being able to scavenge radicals and inhibit lipoxygenase in pumpkin seeds may in part explain the health benefits attributed to them. 相似文献
29.
On the basis of the studies carried out the authors verified a hypothesis that psychosocial work conditions and occupational stress are risk factors for premature birth and newborn hypotrophy. The following aspects were considered in the evaluation of psycho-social work conditions: (a) work-related psychological demands; (b) the extent to what an employee is able to control the situation at work; (c) occupational stress arising from the discrepancy between work-related demands and the extent of control over the work situation; and (d) interpersonal relations at work. The analysis covered 219 cases of premature births and 159 cases of newborn hypotrophy. The control group comprised 586 women sampled randomly who gave birth at term to a healthy baby with correct birth weight. The authors found that ill interpersonal relations and a low level of control over the situation at work elevate the risk of giving birth to a baby with hypotrophy, while good interpersonal relations and a high level of control over the situation at work play a protective role. The effect of these psycho-social factors applied only to hypotrophy of a newborn and it was related neither to other features of occupational work nor to biomedical factors. It seems that this kind of factors may have generally less pronounced impact on premature birth. 相似文献
30.
The analytical power of the differential impedance analysis (DIA) as a new approach for model identification is investigated. The minimum of the ratio q of the two time-constants T1 and T2 (q=T2/T1) describing a two step reaction with ladder structure, at which the second time-constant T2 is recognized, is accepted as a measure for the selectivity evaluation. The investigation is performed on synthetic models with variation of q in the interval from 30 to 0.001. The influence of data quality is studied by applying data truncation from seven to two digits, as well as by introduction of a wild point. Experimental data measured on two actual dummy cells with q equal to 30 and 0.03, respectively, are also analyzed. The results are compared with those obtained by applying the algorithm of the wide-spread complex non-linear least-squares method, performed on zview software product. The comparative study demonstrates a higher selectivity of the DIA, combined with an additional noise immunity and increased robustness of the analysis. 相似文献