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Two issues were investigated in 2 experiments: (1) the validity of a reading span test that combined a knowledge verification task with a secondary task of word memorization and (2) the hypothesis that word recall reflects the amount of working memory that is functional in reading. In Exp 1, the validity and reliability of the reading span measure were determined. In Exp 2, it was reasoned that if word recall reflected functional working memory in reading, then 2 results should be observed. The 1st predicted result was that prior exposure to sentences used in the reading span test would release working memory resources and improve word recall. The 2nd was that word recall, though correlated with general working memory and verbal knowledge measures, would add to these scores in predicting comprehension. Both sets of results were obtained, supporting the hypothesis that the reading span test measures functional working memory in reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
BACKGROUND: Two peat biofilters were used for the removal of toluene from air for one year. One biofilter was fed with pure toluene and the other received 1:1 (by weight) ethyl acetate:toluene mixture. RESULTS: The biofilters were operated under continuous loading: the toluene inlet load (IL) at which 80% removal occurred was 116 g m?3 h?1 at 57 s gas residence time. Maximum elimination capacity of 360 g m?3 h?1 was obtained at an IL of 745 g m?3 h?1. The elimination of toluene was inhibited by the presence of ethyl acetate. Intermittent loading, with pollutants supplied for 16 h/day, 5 days/week, did not significantly affect the removal efficiency (RE). Biomass was fully activated in 2 h after night closures, but 6 h were required to recover RE after weekend closures. Live cell density remained relatively constant over the operational period, while the dead cell fraction increased. Finally, a 15 day starvation period was applied and operation then re‐started. Performance was restored with similar re‐acclimatization period to that after weekend closures, and a reduction in dead cell fraction was observed. CONCLUSION: This study demonstrates the capacity of the system to handle intermittent loading conditions that are common in industrial practices, including long‐term starvation. Copyright © 2008 Society of Chemical Industry  相似文献   
14.
Wax precipitation is one of the most important flow assurance problems. Unfortunately, experimental data are very scarce to confirm existing models for prediction of such precipitation problem. This work reports a new experimental method. Multistage fractional wax precipitation was carried out by decreasing the temperature of crude oil. No solvent dilution was used, so the effect of solvent on temperature wax precipitation was avoided. The reproducibility of the method was tested with comparable results. The precipitation curve and the wax appearance temperature were obtained for two crude oils with different chemical nature using the reported method.  相似文献   
15.
The authors report on the viscoelastic characterization of guar hydrogels obtained through complexation reactions with borax ions. These gels are compared with hydrogels obtained from poly(vinyl alcohol) of different degree of hydrolysis through complexation reactions with congo red. The effect of the degree of hydrolysis and both, the concentration of PVA and the concentration of congo red, on the viscoelastic properties of the hydrogels is analyzed. The potential use of the PVA‐based hydrogels as hydraulic fracturing liquids is discussed in relation to the commonly used fracturing liquid based on the guar–borax system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
16.
A tertiary amine functionalized 4-nitro-4′-alkoxy azobenzene mesogen with a 10 or 12 carbon spacer (azo-nN) was synthesized and complexed in equimolar proportions with poly(acrylic acid) (PA-H) and poly(sulfonic acid) (PSS-H), and investigated by thermogravimetric analysis, differential scanning calorimetry, polarizing optical microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. The neat azo-nN is characterized by a partial bilayer SA mesophase at higher temperatures, and a highly ordered phase, in which the molecules are stacked orthogonally in bilayers, at lower temperatures. As supported by infrared analysis, for the azo-nN/PA-H mixture, the complexation is partial while for the same azo-nN/PSS-H mixture, complete proton transfer occurs. When the azo-nN is blended with the PA-H, regarded as a weak acid, a biphasic system is generated and the thermotropic behavior of neat mesogen is not significantly affected. In contrast, by mixing the same mesogen with a PSS-H (regarded as a strong acid), the thermotropic behavior is significantly influenced: the complexation generated a partial or interdigitated smectic A or tilted smectic C lamellar phase.  相似文献   
17.
Fabrication of alumina-aluminium titanate laminates that combine high strength external layers with flaw tolerant internal layers is limited by the difficulty of the co-sintering of layers with large differences in the green state. This work describes a new method to obtain alumina-aluminium titanate layered materials constituted by layers with large differences in terms of grain size starting from green bodies with similar microstructures. The approach is based on the effect of small amounts of titania (TiO2) as agents for alumina grain growth enhancement. Starting from a fine grained green body that combined alumina layers with composite layers made of mixtures of alumina and titania, a two step sintering schedule led to a layered structure with external layers of small grain sized alumina combined with internal alumina layers with large grain size due to the diffusion of titanium. The large grain sized alumina layers conferred flaw tolerant behaviour to the laminate due to crack branching and bridging.  相似文献   
18.
Summary Physicochemical and organoleptic properties were studied in two batches of four different types of goat's milk cheese: fresh, washed curd, soft with surface flora, and Majorero, frozen for four months prior to ripening and/or chilled storage. Frozen storage did not produce significant changes in the rheological or sensory characteristics of the cheeses, except in the case of fresh cheese, the textural characteristics of which were adversely affected. The level of proteolysis, estimated from the amino-acid nitrogen, was higher in the pre-frozen washed curd, soft with surface flora, and Majorero cheeses. The level of lipolysis was comparable, except in the soft cheese with surface flora, which presented higher levels of free fatty acids when stored frozen before ripening.
Einfluß des Gefrierens und der Gefrierlagerung auf die physikalisch-chemischen und organoleptischen Eigenschaften von vier Ziegenkäsen
Zusammenfassung Aus Ziegenmilch wurden jeweils zwei Chargen von vier spanischen Käsesorten hergestellt: Frischkäse, gewaschene Käsemasse, Weichkäse mit Oberflächenflora und Majorero -Käse. Von jeder Charge wurde die Hälfte gefroren gelagert und erst nach vier Monaten auf die übliche Weise gereift und/oder gekühlt aufbewahrt. Die physikalisch-chemischen und organoleptischen Eigenschaften wurden danach untersucht. Im Vergleich mit Käsen, die nicht gefroren gewesen waren, ergaben sich keine wesentlichen Unterschiede in den rheologischen und sensorischen Eigenschaften, mit Ausnahme bei den Frischkäsen, bei dem sich die Textur durch die Aufbewahrung in gefrorenem Zustand verschlechtert hatte. Der Gehalt an freien Aminosäuren, ein Maß für die Proteolyse, war höher in der gewaschenen Käsemasse, in dem Weichkäse mit Oberflächenflora und in dem Majorero-Käse, die vier Monate gefroren gewesen waren. Durch die Gefrierlagerung hatte sich der Fettabbau nicht verändert, mit Ausnahme bei dem Käse mit Oberflächenflora, bei dem der Gehalt an freien Fettsäuren erhöht war im Vergleich mit dem Käse, der nicht vier Monate gefriergelagert worden war.
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19.
Summary The flavonoids present in ten selected samples of La Alcarria honey with different pollen compositions have been HPLC analysed in order to establish if correlations between botanical origin and flavonoid profiles are possible. A common flavonoid pattern is observed in the different samples showing that pollen is not the main source of honey flavonoids. A close correlation between the flavonoid patterns of honey flavonoids and propolis flavonoids has been found suggesting that flavonoid analysis could be more useful in geographical origin determinations than in botanical origin studies.
Flavonoide des La-Alcarria-Honigs Eine Studie ihres botanischen Ursprungs
Zusammenfassung Die Flavonoide in Proben in Alcarria-Honig mit unterschiedlicher Pollenzusammensetzung wurden untersucht, um Kortrelationen zwischen dem botanischen Ursprung und den möglichen Flavonoiden zu finden. In den verschiedenen Proben wurde ein Flavonoid-Muster gefunden, wobei der Pollen nicht die Hauptquelle der Honigflavonoide ist. Es wurde jedoch eine enge Korrelation zwischen den Flavonoid-Mustern des Honigs und des Bienenkittharzes gefunden, was für die geographische Herkunft wichtiger ist als die botanische.
  相似文献   
20.
Iranian Polymer Journal - The present work focuses on the assessment of the ability of porcine plasma protein (PPP) to be electrospun satisfactorily to form fibre mats, and their rheological and...  相似文献   
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