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排序方式: 共有1861条查询结果,搜索用时 31 毫秒
71.
In this paper, we investigate formulation of non-local memory effect hysteretic loops in presliding domain of friction by examining the dynamic responses of a single-degree-of-freedom friction oscillator. We modify the Maxwell slip model introducing characteristic features of asperities and perform detailed examination of the system from two perspectives. The first one, termed by us as microscale, presents contribution of each individual asperity to the total friction force, whereas the second one, termed by us as macroscale, concerns friction force behaviour of the whole model treated as the unity, with a special emphasis on non-local memory effect hysteretic loops formulation, complemented by time responses. 相似文献
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Urszula Krupa-Kozak Natalia Drabińska Cristina M. Rosell Costantino Fadda Andrzej Anders Tomasz Jeliński Anita Ostaszyk 《International Journal of Food Science & Technology》2019,54(4):1121-1129
Broccoli by-products, in particular leaves, are rich sources of nutritional and bioactive components thus could constitute a valuable food additive. Although an upsurge in quantity of gluten-free products is observed further studies are required on improvement of their nutritional quality and palatability. This study aimed to investigate the influence of broccoli leaf powder (BLP) on dough behaviour, and technological characteristics and sensory quality of gluten-free mini sponge cake (GFS). Broccoli leaf powder replaced an equivalent amount (2.5%, 5%, 7.5%; w/w) of corn and potato starches in GFS formulation. Applied BLP increased the instrumental firmness of GFS but sensorial attributes (elasticity, crustiness, mastication and adhesiveness) were similar to the control. All broccoli GFS were vividly green, had small size pores properly distributed. Among them, sample with 2.5% BLP was distinguished for its desirable sensory quality, despite a slightly perceived cabbage aroma and taste. Moderate amount of BLP allows to preserve a good quality GFS improving its attractiveness and palatability. 相似文献
74.
A practical computing algorithm has been developed for calculating the reflection high-energy electron diffraction (RHEED) from the molecular beam epitaxy growing surface. The calculations are based on the use of the dynamical diffraction theory in which the electrons are taken to be diffracted by a potential, which is periodic in the dimension perpendicular to the surface. The computer program presented in this paper enables calculations for three basic types of diffuse potential for crystalline heteroepitaxial structures, including the possible existence of various diffuse scattering models through the layer parallel to the surface. 相似文献
75.
Giuseppe Grosso Stefano Marventano Justin Yang Agnieszka Micek Andrzej Pajak Luca Scalfi 《Critical reviews in food science and nutrition》2017,57(15):3218-3232
Many studies have reported that higher adherence to Mediterranean diet may decrease cardiovascular disease (CVD) incidence and mortality. We performed a meta-analysis to explore the association in prospective studies and randomized control trials (RCTs) between Mediterranean diet adherence and CVD incidence and mortality. The PubMed database was searched up to June 2014. A total of 17 studies were extracted and 11 qualified for the quantitative analysis. Individuals in the highest quantile of adherence to the diet had lower incidence [relative risk (RR): 0.76, 95% confidence intervals (CI): 0.68, 0.83] and mortality (RR: 0.76, 95% CI: 0.68, 0.83) from CVD compared to those least adherent. A significant reduction of risk was found also for coronary heart disease (CHD) (RR: 0.72, 95% CI: 0.60, 0.86), myocardial infarction (MI) (RR: 0.67; 95% CI: 0.54, 0.83), and stroke (RR: 0.76; 95% CI: 0.60, 0.96) incidence. Pooled analyses of individual components of the diet revealed that the protective effects of the diet appear to be most attributable to olive oil, fruits, vegetables, and legumes. An average reduced risk of 40% for the aforementioned outcomes has been retrieved when pooling results of RCTs. A Mediterranean dietary pattern is associated with lower risks of CVD incidence and mortality, including CHD and MI. The relative effects of specific food groups should be further investigated. 相似文献
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Barbara Mendrek Łukasz Sieroń Marcin Libera Mario Smet Barbara Trzebicka Aleksander L. Sieroń Andrzej Dworak Agnieszka Kowalczuk 《Polymer》2014
Core-shell type stars synthesized via atom transfer radical polymerization were used for the delivery of nucleic acids. The interior of the stars consisted of hyperbranched poly(arylene oxindole), while the arms were composed of poly(N,N-dimethylaminoethyl methacrylate). The length of the star arms varied in degree of polymerization (DP) from 14 to 98. The hydrodynamic radius of the structures measured in water indicated the presence of small aggregates, while isolated stars ranging in size from 14 to 29 nm were seen in organic solvent. The phase transition temperatures of the stars in water, measured in basic conditions, were shifted to lower values with increasing DP of the arms. Stable polyplexes of stars with plasmid DNA were formed. Their size varied from 300 nm to 400 nm, depending upon the DP of arms. The zeta potential of the polyplexes was positive, which facilitated their cellular uptake. The DP of the arms influenced the transfection efficiency of HT-1080 cells, demonstrating that stars are promising candidates for synthetic gene vectors. 相似文献
78.
Christian Wolkersdorfer Rob Bowell Ingar F. Walder Steinar Nilssen Marja Liisa R?is?nen P?ivi Heikkinen Kari Pulkkinen Kirsti Korkka-Niemi Veli-Pekka Salonen Georgia Destouni Andrea Hasche Andrzej J. Witkowski A. Blachère S. Morel D. Lefort Sanda Mid?i? Irem Silajd?i? R. H. Coulton K. P. Williams Ben Rees Kevin B. Hallberg D. Barrie Johnson 《Mine Water and the Environment》2012,31(3):237-238
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