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排序方式: 共有557条查询结果,搜索用时 15 毫秒
551.
Laura Bayés-García Eduard Colomer-Llombart Mercedes Aguilar-Jiménez Teresa Calvet 《Journal of the American Oil Chemists' Society》2021,98(11):1093-1105
High-commercial-value products are often susceptible to food fraud. Among them, Iberian dry-cured ham is highly appreciated due to its particular and sensory, but also nutritional, properties. There are four different Iberian ham categories (namely bellota, recebo, cebo de campo and cebo), which directly depend on the rearing system of the pig during the last stage of the fattening phase. However, there is still a lack of a normalized and robust method capable of authenticating the different product categories and, therefore, preventing mislabeling. In the present work, we characterized the polymorphic behavior of raw (before curing) lipid extracts belonging to the four categories of Iberian pig. A total of 80 different samples were analyzed by DSC, and synchrotron radiation XRD experiments were carried out for selected ones. The results obtained showed that bellota and recebo categories exhibited essentially the same crystallization and polymorphic behavior and this was significantly different (p < 0.05) from that of cebo de campo and cebo. The latter exhibited higher crystallization and melting temperatures than bellota and recebo samples, due to the occurrence of an additional β′-2L polymorphic form. By considering the differences in rearing systems of pigs belonging to the different categories, we concluded that the key factor which determined the polymorphism of Iberian pig lipid extracts was not the physical exercise practiced by the pig, but the inclusion of acorns in the feeding system. This work demonstrated that thermal and crystallographic techniques, like DSC and XRD, may be promoted to be used as fingerprinting tools for the authentication of high-value food products. 相似文献
552.
Adriana Dantas Silvani Verruck Gabriela Rodrigues de Liz Eduard Hernandez Elane Schwinden Prudencio 《International Journal of Food Science & Technology》2021,56(5):2132-2145
Bifidobacterium BB-12 was microencapsulated by spray drying using lactose-free milk, lactose-free milk and inulin, and lactose-free milk and oligofructose, resulting in powders 1, 2 and 3, respectively. The highest encapsulation yield (88.01%) and the highest bifidobacteria viability during 120 days of storage were noted for spray-dried powder 2. Spray-dried powders 1 and 3 show a higher tendency to yellow colour. After being submitted to in vitro-simulated gastrointestinal conditions, the best probiotic survival rate result was found for spray-dried powder 3 (87.59%). Therefore, spray-dried powders containing prebiotics were the most appropriate combinations for microencapsulation of Bifidobacterium BB-12 and maintenance of cell viability during storage and gastrointestinal system, showing great potential to be used in lactose-free dairy products. 相似文献
553.
Artem Musiienko Davide Raffaele Ceratti Jindřich Pipek Mykola Brynza Hassan Elhadidy Eduard Belas Marián Betušiak Geraud Delport Petr Praus 《Advanced functional materials》2021,31(48):2104467
The interaction of free carriers with defects and some critical defect properties are still unclear in methylammonium lead halide perovskites (MHPs). Here, a multi-method approach is used to quantify and characterize defects in single crystal MAPbI3, giving a cross-checked overview of their properties. Time of flight current waveform spectroscopy reveals the interaction of carriers with five shallow and deep defects. Photo-Hall and thermoelectric effect spectroscopy assess the defect density, cross-section, and relative (to the valence band) energy. The detailed reconstruction of free carrier relaxation through Monte Carlo simulation allows for quantifying the lifetime, mobility, and diffusion length of holes and electrons separately. Here, it is demonstrated that the dominant part of defects releases free carriers after trapping; this happens without non-radiative recombination with consequent positive effects on the photoconversion and charge transport properties. On the other hand, shallow traps decrease drift mobility sensibly. The results are the key for the optimization of the charge transport properties and defects in MHP and contribute to the research aiming to improve perovskite stability. This study paves the way for doping and defect control, enhancing the scalability of perovskite devices with large diffusion lengths and lifetimes. 相似文献
554.
The effect of several mixing process parameters on the concentration of carbon black particles at the interface between the polymer components in polyethylene–polystyrene mixtures was studied. It was established that the process of particle transport from the polymer phase to the interface happens only under the action of shear deformation, but simultaneously acting shear stresses prevent particle concentration. The nanoparticle accumulation at the interface is determined not only by how favored this process is thermodynamically, but also by the parameters of the mixing process. The filler concentration at the interface is facilitated by a reduction in the shear stress, polymer viscosity, filler particle size, and preliminary injection of filler into the polymer component that is less effective at wetting the filler surface. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48585. 相似文献
555.
Aleksandr Amirkhanov Matthias Bernhard Alexey Karimov Sabine Stiller Andreas Geier M. Eduard Gröller Gabriel Mistelbauer 《Computer Graphics Forum》2020,39(7):635-646
Dental healthcare increasingly employs computer-aided design software, to provide patients with high-quality dental prosthetic devices. In modern dental reconstruction, dental technicians address the unique anatomy of each patient individually, by capturing the dental impression and measuring the mandibular movements. Subsequently, dental technicians design a custom denture that fits the patient from a functional point of view. The current Workflow does not include a systematic analysis of aesthetics, and dental technicians rely only on an aesthetically pleasing mock-up that they discuss with the patient, and on their experience. Therefore, the final denture aesthetics remain unknown until the dental technicians incorporate the denture into the patient. In this Work, we present a solution that integrates aesthetics analysis into the functional Workflow of dental technicians. Our solution uses a video recording of the patient, to preview the denture design at any stage of the denture design process. We present a teeth pose estimation technique that enables denture preview and a set of linked visualizations that support dental technicians in the aesthetic design of dentures. These visualizations assist dental technicians in choosing the most aesthetically fitting preset from a library of dentures, in identifying the suitable denture size, and in adjusting the denture position. We demonstrate the utility of our system with four use cases, explored by a dental technician. Also, we performed a quantitative evaluation for teeth pose estimation, and an informal usability evaluation, with positive outcomes concerning the integration of aesthetics analysis into the functional Workflow. 相似文献
556.
Minds and Machines - Healthcare robots enable practices that seemed far-fetched in the past. Robots might be the solution to bridge the loneliness that the elderly often experience; they may help... 相似文献
557.
Victor Mendoza Eirini Katsidoniotaki Markos Florentiades Jorge Dot Fraga Eduard Dyachuk 《风能》2023,26(6):521-537
In this work, a closely spaced dual turbine concept is studied. The distance between the two side-by-side hubs is 1.05 , where is the rotor diameter. This configuration has a potential benefit for offshore wind developments in which power density can be maximized. The main goal is to evaluate the overall aerodynamic performance, blade loads, and wake structure of a reference wind turbine generator operating within this dual turbine configuration and to compare the effects against those for the typical single turbine configuration. For this purpose, an actuator line model has been employed together with the large eddy simulation approach for predicting the turbulence effects. This model was implemented by using the open-source computational fluid dynamics toolbox OpenFOAM. Results show a better performance for the dual turbine concept. Under same operating conditions, the aerodynamic power of each turbine within the dual concept is higher than the power of the stand alone turbine, particularly at lower operating wind speeds (approximately 2% to 3% of extra power per turbine). Comparison between the two configurations shows similar character of the tangential and normal forces acting on the blades in terms of magnitude and fluctuation, eliminating potential concerns regarding fatigue and blade design. The largest difference in the tangential and normal root bending moments are approximately 3% and 2%, respectively, between single and dual turbine configurations. Finally, wake recovery analysis shows a downwind velocity deficit that is not enhanced streamwise in the dual turbine configuration with no considerable difference after 7 . 相似文献