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121.
Fatma Nur Arslan Huseyin Kara Hamide Filiz Ayyildiz Mustafa Topkafa Ismail Tarhan Adnan Kenar 《Journal of the American Oil Chemists' Society》2013,90(8):1179-1193
The main goal of the present study was (i) to determine the formation of degradation products in cottonseed oil (CSO) blends during deep frying process by adsorption and high performance size exclusion chromatography techniques and (ii) to evaluate the impacts of food additives on total polar (TPC) and polymeric compound (PTAG) formation using a chemometric approach. In order to prepare the frying CSO blends; ascorbic palmitate, mixed tocopherols, dimethylpolysiloxane, lecithin and sesame oils were used as additives. To determine the real impacts of additives, a quarter-fraction factorial experimental design with two levels and five factors was used. The changes in TPC and PTAG data were carefully evaluated during 10 h of frying at 170 ± 5 °C with normal distribution (ND) graphs and analyzed using a one-way analysis of variance (ANOVA), followed by Tukey’s Post-hoc test (α = 0.05). The results indicated that the increasing values for TPC and PTAG during the frying processes for all blends, TPC and PTAG contents reached maximum levels of 16.37 and 6.01 % respectively, which are below the limit values stated by official authorities for the quality assessment of frying oils. The ANOVA test results were in good agreement with ND graphs and data indicated that the impact of mixed tocopherols was significant for TPC formation, meanwhile the impact of lecithin and ascorbic palmitate × dimethylpolysiloxane were significant for PTAG formation. Thus, the present study should be considered to be a very useful guide for developing new frying oil formulations based on CSO by using food additives. 相似文献
122.
Using event-related potentials (ERPs), the authors investigated the influences of sentence context, semantic memory organization, and perceptual predictability on picture processing. Participants read pairs of highly or weakly constraining sentences that ended with (a) the expected item, (b) an unexpected item from the expected semantic category, or (c) an unexpected item from an unexpected category. Pictures were unfamiliar in Exp 1 but preexposed in Exp 2. ERPs to pictures reflected both contextual fit and memory organization, as do ERPs to words in the same contexts (K. D. Federmeier and M. Kutas, see record 1999-15076-002). However, different response patterns were observed to pictures than to words. Some of these arose from perceptual predictability differences, whereas others seem to reflect true modality-based differences in semantic feature activation. Although words and pictures may share semantic memory, the authors' results show that semantic processing is not amodal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
在激烈的市场竞争条件下,洗衣机产品的发展给了工程师们进行创造性设计的机会。洗衣机和烘干机不单单看作基本必需品,更应看作一种耗能商品。因此,生产制造者必须注意改变消费者那种“只要能洗净衣服,操作简单就可以算完美的洗衣机”的想法。1节约能源越来越受到重视 最近,美国通过了一系列有关立法议案。一月正式实施后,更将推动洗衣设备的设计与制造。新的能源效率标准最终还是要求洗涤设备消耗较少的能源。 惠尔浦副总裁Cunninghan指出,在北美,特别在美国,我们希望在2000年能作出洗衣设备统一的标准。为在法规确… 相似文献
124.
Betina Giehl Zanetti-Ramos Mauricia Beddin Fritzen-Garcia Cristian Schweitzer de Oliveira André Avelino Pasa Valdir Soldi Redouane Borsali Tânia Beatriz Creczynski-Pasa 《Materials science & engineering. C, Materials for biological applications》2009,29(2):638-640
Nanoparticles have applications in various industrial fields principally in drug delivery. Nowadays, there are several processes for manufacturing colloidal polymeric systems and methods of preparation as well as of characterization. In this work, Dynamic Light Scattering and Atomic Force Microscopy techniques were used to characterize polyurethane nanoparticles. The nanoparticles were prepared by miniemulsion technique. The lipophilic monomers, isophorone diisocyanate (IPDI) and natural triol, were emulsified in water containing surfactant. In some formulations the poly(ethylene glycol) was used as co-monomer to obtain the hydrophilic and pegylated nanoparticles. Polyurethane nanoparticles observed by atomic force microscopy (AFM) were spherical with diameter around 209 nm for nanoparticles prepared without PEG. From AFM imaging two populations of nanoparticles were observed in the formulation prepared with PEG (218 and 127 nm) while dynamic light scattering (DLS) measurements showed a monodisperse size distribution around 250 nm of diameters for both formulations. The polydispersity index of the formulations and the experimental procedures could influence the particle size determination with these techniques. 相似文献
125.
In 3 experiments, we investigated the hypothesis that age-related differences in working memory might be due to the inability to bind content with context. Participants were required to find a repeating stimulus within a single series (no context memory required) or within multiple series (necessitating memory for context). Response time and accuracy were examined in 2 task domains: verbal and visuospatial. Binding content with context led to longer processing time and poorer accuracy in both age groups, even when working memory load was held constant. Although older adults were overall slower and less accurate than young adults, the need for context memory did not differentially affect their performance. It is therefore unlikely that age differences in working memory are due to specific age-related problems with content-with-context binding. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
126.
delBarco-Trillo Javier; Gulewicz Kara; Johnston Robert E. 《Canadian Metallurgical Quarterly》2009,123(4):758
Efficient discrimination between individuals of closely related species is important to maximize reproductive potential. Some studies using males as subjects have indicated that the medial amygdala (MeA) is involved in discrimination between odors of conspecific females and females from distantly related species. The authors investigated the involvement of the MeA in discrimination by females between odors of conspecific males and odors of males of a closely related species. The authors exposed estrous or diestrous female hamsters (Mesocricetus auratus) to saline, conspecific male odors, or heterospecific (M. brandti) male odors and quantified the expression of c-fos–related antigens in the anterior and posterior MeA. They found that estrous (but not diestrous) females investigated conspecific male odors longer than heterospecific male odors. Neural activity in both the anterior and the posterior MeA was higher in estrous than in diestrous females. In the anterior MeA, there were no significant differences in response to odors of conspecific and heterospecific males. In the posterior MeA, however, neural activity was higher when estrous females were exposed to conspecific odors than when they were exposed to heterospecific odors. No such difference was observed in diestrous females. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
The sorption of anionic ligands such as I−, Br−, and SCN− onto diaminoethyl–sporopollenin (DAE–sporopollenin) was investigated in both column and batch experiments at room temperature. The isotherm binding constants suggest that the resin is most efficient at the binding of I− compared with Br− or SCN−. The general ligand sorption affinity series observed was I− > Br− > SCN−. This ligand sorption could be described by considering the hydration of ions in the exchanger. The sorption behavior of the ligand exchanger and the possibilities of selectively removing and recovering ligands are discussed on the basis of their chemical and complexing properties. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 771–774, 1998 相似文献
128.
The transducer characteristics of hydrophones manufactured from porous 3–3 piezocomposites are compared with dense piezoceramic disc hydrophones using finite element modelling. Due to the complex porous structure of the 3–3 piezocomposites, a real-size 3-dimensional model was developed while a 2-dimensional axisymmetric model was constructed for the simple dense disc hydrophone. The electrical impedance and receiving sensitivity of the hydrophones in water were evaluated in the frequency range 10–100 kHz. The model results were compared with the experimental results. The sharp resonance peaks observed for the dense piezoceramic hydrophone were broadened to a large extent for porous piezocomposite hydrophones due to weaker coupling of the structure. The receiving sensitivity of piezocomposite hydrophones is found to be constant over the frequency range studied. The flat frequency response suggests that the 3–3 piezocomposites are useful for wide-band hydrophone applications. 相似文献
129.
The crystallization and sintering behaviour of a premullite powder which had been synthesized from aluminium sulphate [Al2(SO4)3· 16H2O] and colloidal silicon dioxide have been studied. Calcination of the mixture at 860 °C for 12 h gives a very active powder (surface area – 188 M2g–1) in the form of spine] and mullite forms via this spinel phase. The non-mullitized powder can be reactively sintered at 1500–1550°C to 97%–99% density in 3–5 h with a very fine microstructure. 相似文献
130.
Abstract Electrogastrogram (EGG) is the cutaneous recording of gastric electrical activity. Some patients with nausea, vomiting, early satiety, and patients with long term insulin‐dependent diabetes exhibit gastric electrical rhythm disturbances. We are interested in investigating the EGG to determine if abnormalities of the EGG occur in association with those gastric complaints. The aim of this document is to investigate long term diabetics with a history of such gastric dysrhythmia complaints in an effort to further characterize the frequency of abnormalities of the EGG in real clinical diabetic gastroparesis patients. For feature extraction purposes, we have performed Wavelet‐Packet analysis of EGG signals and have obtained power spectral density of wavelet‐packet details and approximation coefficients in diabetic patients suffering from gastric dysrhythmia (tachygastria, bradygastria) and healthy volunteers. Wavelet‐Packet analysis provides details of changes in frequency components at any time point, and enhanced interpretation of cutaneous EGG recordings. In conclusion, this paper has shown that the Wavelet‐Packet analysis method is very useful in the analysis of cutaneous EGG recordings, especially in detecting dysrhythmic events. 相似文献