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31.
32.
Katarzyna Skryplonek Marta Henriques David Gomes Jorge Viegas Catarina Fonseca Carlos Pereira Izabela Dmytrów Anna Mituniewicz-Małek 《Journal of dairy science》2019,102(9):7838-7848
Frozen yogurt is a type of dairy product that is considered to be a more healthful alternative to conventional ice cream due to its lower fat content and the presence of viable lactic acid bacteria. Lactose-free products are a growing trend in the dairy industry, and lactose-free yogurts and ice creams can both be found on the market. However, lactose-free frozen yogurt has not yet reached the market. In this study, we aimed to investigate the effect of adding κ-carrageenan (0.05, 0.1, and 0.15%) and corn starch (1, 2, and 3%) on acidity, texture, viscosity, overrun, melting properties, color attributes, and sensory characteristics of lactose-free frozen yogurts. Lactose was reduced by enzymatic hydrolysis during the fermentation process. The effectiveness of the hydrolysis was measured by HPLC, and lactose was reduced to 0.05% after 80 min of incubation with the enzyme. The addition of stabilizers did not change overrun and melting properties of frozen yogurt, but it did affect pH, titratable acidity, and color parameters. The product with 0.15% κ-carrageenan had the highest hardness and stickiness values. Moreover, κ-carrageenan had a positive effect on sensory attractiveness of lactose-free frozen yogurt, and it reduced the coarse texture in comparison with the control without stabilizers. A lactose-free frozen yogurt with good quality and nutritional characteristics was produced, particularly with the use of κ-carrageenan as stabilizer. 相似文献
33.
Electrical discharge machining (EDM) is one of the most widely disseminated manufacturing technologies, in particular as regards the generation of accurate and complex geometrical shapes on hard metallic components. Nevertheless current EDM technologies have major limitations when dealing with fine surface finish over large process area. Indeed this is one reason that explains the need of final manual polishing of mould cavities performed by EDM. Recently EDM with powder-mixed dielectric (PMD-EDM) has been a focus of an intense research work in order to overcome these technological performance barriers. This paper presents a research work within the objective to acquire deep knowledge on EDM technology with powder mixed dielectric and to compare its performance to the conventional EDM when dealing with the generation of high-quality surfaces. In particular the analysis of the effect of the electrode area in the surface quality measured by the surface roughness and craters morphology was carried out for both technologies. The results achieved evidenced a linear relationship between the electrode area and the surface quality measures as well as a significant performance improvement when the powder mixed dielectric is used. 相似文献
34.
E.C.T. Ramos D.R. dos Santos C.A.A. Cairo V.A.R. Henriques A.S. Ramos 《Journal of Alloys and Compounds》2009,483(1-2):190
The absence of brittle phases and elevated temperature during ball milling of a powder mixture containing a large amount of ductile component can contribute to reach an excessive agglomeration denoting a critical ball milling (CBM) behavior. This work reports in the effect of composition and milling parameters on the CBM behavior of Ti–Si–B powders. High-purity elemental Ti–Si–B powder mixtures were processed in a planetary ball mill in order to prepare the Ti6Si2B compound and two-phase Ti + Ti6Si2B alloys. TiH2 chips instead of titanium powder were used as a starting material. To avoid elevated temperature in the vials during ball milling of Ti–Si–B powders the process was interrupted after each 10 min followed by air-cooling. Following, the milled powders were hot-pressed at 900 °C for 1 h. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). Short milling times followed by air-cooling contributed to obtain a large amount of powders higher than 75% in the vials. Only Ti and TiH2 peaks were observed in XRD patterns of Ti–Si–B and TiH2–Si–B, respectively, suggesting that extended solid solutions were achieved. The large amount of Ti6Si2B and Ti + Ti6Si2B structures were formed during hot pressing from the mechanically alloyed Ti–Si–B and TiH2–Si–B powders. 相似文献
35.
2)香波洗涤条件
按照泡沫均质搅拌测试的要求备好香波样品,将样品加热至40℃后放入颗粒图像测量仪的玻璃贮液器。启动测量仪成像系统后,将发束放入配方液,浸泡约30s,随后清洗30s,风干。 相似文献
36.
C. Torre-Abreu M.F. Ribeiro C. Henriques F.R. Ribeiro 《Applied catalysis. B, Environmental》1997,13(3-4):251-264
CuMOR catalysts with different Si/Al ratios and copper contents, prepared from the acid and sodium forms, were studied in NO reduction with propene in the presence of excess oxygen. It was observed that the influence of zeolite Si/Al ratio on CuMOR catalytic activity for NO SCR by propene depends on the catalyst copper content, the reverse being also true. For mordenites prepared from the acid form, it was shown that the most active catalyst must have 60% of copper exchange, whereas for those prepared from the sodium form, the maximum catalytic activity is obtained for catalysts with 20% of copper exchange. Moreover, it was observed that at low copper-exchange levels, the catalyst prepared from the sodium form exhibits much higher activity than those prepared from the acid form. Although, when the copper-exchange level increases, the effect of zeolite form is less pronounced. Thus, it was indicated that Brönsted acidity does not promote the NO selective reduction by propene. 相似文献
37.
When evaluating the acceptability of food products, companies often focus on specific demographics for recruiting and screening consumers. However, this information may not necessarily explain the variability in the test results. Other elements, such as consumer psychographic profiles, may help better understand test participants’ responses. The objective of this study was to investigate the effect of food neophobia (reluctance to/avoidance of novel foods) on acceptability of novel food items. Six salad dressings with novel flavor combinations were chosen for evaluation in a central location test. Consumers were screened using the food neophobia scale (Pliner & Hobden, 1992) as well as liking of salad dressings. Each subject evaluated three of six dressings for hedonic and diagnostic attributes. Neophobic subjects rated the salad dressings significantly lower (p < 0.05) than neophilics for all hedonic attributes with the exception of appearance. These results were consistent for all dressings. However, when looking at the hedonic mean scores from both groups, the products were ranked in similar order in that the best liked and least liked dressing for the neophilic group was the same as those for the neophobic group. For diagnostic attributes, while the mean scores were significantly different for neophobics and neophilics, the percentage of “just-about-right” scores did not differ. These results suggest that food neophobia may impact the degree with which a product is liked or disliked by consumers, but it may not affect how products are ranked based on hedonic mean scores. Therefore, while understanding the psychographic composition of a consumer test respondent base may help explain why some products score higher or lower in acceptability, it may not alter the sensory guidance provided to product development regarding the specific flavor and texture attributes that were tested. 相似文献
38.
Fragility curve probabilistic model applied to durability and long term mechanical damage of masonry
Elsa Garavaglia Anna Anzani Luigia Binda Giuliana Cardani 《Materials and Structures》2008,41(4):733-749
In view of preserving the historical heritage, the deterioration processes of masonry materials and the long term damage of
multiple leaf historic buildings is studied from an experimental and a numerical point of view. Durability tests and pseudo-creep
tests have been carried out and interpreted through probabilistic models for the service life prediction. The precocious recognition
of structural critical states will allow to design repair and strengthening interventions and to prevent total or partial
failure of the constructions. 相似文献
39.
The outline for theoretically unified psychology is offered. A new epistemological system is used to provide a unique vantage point to examine how psychological science exists in relationship to the other sciences. This new view suggests that psychology can be thought of as existing between the central insights of B. F. Skinner and Sigmund Freud. Specifically, Skinner's fundamental insight is merged with cognitive neuroscience to understand how mind emerges out of life. This conception is then joined with Freud's fundamental insight to understand the evolutionary changes in mind that gave rise to human culture. By linking life to mind from the bottom and mind to culture from the top, psychology is effectively boxed in between biology and the social sciences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
This paper presents an analysis of the data collected in the ambient vibration test of the International Guadiana cable-stayed Bridge, which links Portugal and Spain, based on different output-only identification techniques: peak-picking, frequency domain decomposition, covariance-driven stochastic subspace identification, and data-driven stochastic subspace identification. The purpose of the analysis is to compare the performance of the four techniques and evaluate their efficiency in dealing with specific challenges involved in the modal identification of the tested cable-stayed bridge, namely the existence of closely spaced modes, the perturbation produced by the local vibration of stay-cables, and the variation of modal damping coefficients with wind velocity. The identified natural frequencies and mode shapes are compared with the corresponding modal parameters provided by a previously developed numerical model. Additionally, the variability of some modal damping coefficients is related with the variation of the wind characteristics and associated with a component of aerodynamic damping. 相似文献