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131.
From the knowledge of ionic injection from metal electrodes in an insulating liquid, the modeling of geophysical flows is proposed. More particularly, it would be desirable to the general atmospheric circulation with a laboratory experiment where an insulating liquid, lying between two metal electrodes (a spherical one and an ellipsoid one) is subjected to both an electric force and the effect of rotation around an axis. The first step in solving this problem is to study the hydrodynamic stability of an insulating incompressible liquid layer lying between two concentric conducting spheres subjected to a unipolar injection by one or the other of the two spheres. The linear critical conditions are determined for various values of the different parameters. Secondly, we take into account the ellipticity of one electrode in a circulation model by studying the flow of a liquid between two planes lying at a small angle to each other. The experiments exhibit such a flow in conditions where volumic conduction is still dominant. An explanation is proposed which accounts for the variation law and the order of magnitude of the liquid velocity. 相似文献
132.
133.
An optical method has been developed to provide quantitative results useful for characterizing the crazing of transparent plastics. The procedure consists of the detection of discontinuities in a beam of light that scans the specimen in a direction perpendicular to the line of crazing. The light is transmitted to a photomultiplier that is connected with an amplifying system and a recorder that provides a diagram of the light energy modulated by the lines of crazing. The specimen is scanner both before and after subjecting it to a treatment that causes crazing, and the crazing index is considered to be the difference between the area below the two curves. 相似文献
134.
Impact of diet supplemented with microencapsulated condensed tannins on cow milk nutritional profile
Attilio Matera Lucia Sepe Silvia Vincenzetti Roberta Tolve Nicola Condelli Salvatore Claps Francesco Genovese Annamaria Ricciardi Teresa Zotta Teresa Scarpa Maria Antonietta Di Napoli Giulia Francesca Cifuni Paolo Polidori Giuseppe Santini Luciano Scarano Giuseppe Altieri Giovanni Carlo Di Renzo Sofia Renzi Marilisa Giavalisco Fernanda Galgano 《International Journal of Dairy Technology》2023,76(4):813-827
Feed production systems should consider more sustainable solutions to reduce the pressure on earth's finite resources. In this work, we investigated the effect of microencapsulated condensed tannins (MCTs)-enhanced diet on the cow milk characteristics. The diet reduced the urea content, while preserved and the n-3 and n-6 portion of fatty acids. Aside from the rising of vitamin C level, MCTs had a negative effect on the amount of B group vitamins. MCTs may be considered a promising feed supplement that offers a good trade-off in terms of milk chemical quality while increasing the environmental sustainability of cattle livestock. 相似文献
135.
Seismic and fire design of a building structure may be two very demanding tasks, especially if included in a performance based design philosophy. For the time being, the necessary harmonization on the regulations concerning these two design fields is almost missing, thus preventing the effective possibility of an integrated design. Besides, while many countries have already moved towards the use of performance-based codes for seismic design, the application of such methodologies for the fire design of structures is still limited in scope. Within this framework, the development of suitable procedures introducing structural fire performance issues for a comprehensive design methodology is needed.In this paper, a numerical investigation for the assessment of the structural fire performance of earthquake resistant composite steel–concrete frames is presented. With reference to a case study defined in the framework of a European Research Project, a great effort was devoted to the identification of the key structural parameters allowing for a possible correlation between the predictable performances under seismic and fire loadings, when these two are considered as independent actions.At the conceptual design level, the most suitable structural solution with respect to both design actions was chosen, including composite beams and circular steel concrete-filled columns. The frame was designed in order to resist severe seismic action according to the ductile design approach provided by Eurocode 8; the parameters affecting members’ sizing were outlined in this phase. Afterwards, the seismic performance of the designed frame was investigated by means of non-linear static analyses; once the seismic performance objectives were met, in order to evaluate the structural fire performance of the whole frame a set of criteria was defined. To this purpose, thermo-mechanical analyses under different boundary conditions were developed and in order to identify the possible mechanisms leading to structural failure, the state of stress at the critical cross-sections at different times of fire exposure was investigated. Another point of main concern was represented by the assessment of the influence of different restraining conditions on the achieved fire resistance rating and kind of structural failure.Moreover, the proposed methodology allowed making an estimate of the amount of axial restraint provided to the heated beams by the surrounding structure; in this view, the importance of choosing column elements in function of their flexural stiffness was revealed, in order to correlate it with the predictable performances under both seismic and fire loadings. 相似文献
136.
Luana Persano Sandra Molle Salvatore Girardo Antonio A. R. Neves Andrea Camposeo Ripalta Stabile Roberto Cingolani Dario Pisignano 《Advanced functional materials》2008,18(18):2692-2698
In this work we demonstrate the nanopatterning of nanocomposites made by luminescent zinc oxide nanoparticles and light‐emitting conjugated polymers by means of soft molding lithography. Vertical nanofluidics is exploited to overcome the polymer transport difficulties intrinsic in materials incorporating nanocrystals, and the rheology, fluorescence, absolute quantum yield, and emission directionality of the nanostructured composites are investigated. We study the effect of patterned gratings on the directionality of light emitted from the nanocomposites, finding evidence of the enhancement of forward emitted light, due to the printed wavelength‐scale periodicity. These results open new possibilities for the realization of nanopatterned devices based on hybrid organic‐inorganic systems. 相似文献
137.
Salvatore Vittorio 《中国集成电路》2008,17(12):58-65
1加密技术-综述
我讲话时总是被窃听,这是隐私,请从我的电话线上走开!请告诉我什么时候我才能有隐私。一Ray Davies和Dave Davies(这是英国摇滚乐队The Kinks的戴维斯兄弟所写的歌词) 相似文献
138.
139.
Salvatore Pontarelli Marco Bonola Giuseppe Bianchi 《International Journal of Network Management》2019,29(1)
Recently, with new hardware architectures such as Reconfigurable Match Tables and languages such as P4, the Software Defined Networking community has started to bring line‐rate data plane programmability inside switching chipsets. Starting from the original OpenFlow's match/action abstraction, most of the work has so far focused on key improvements in matching flexibility. Conversely, the “action part,” ie, the set of operations (such as encapsulation or header manipulation) performed on packets after the forwarding decision, has received way less attention. Goal of this paper is to move beyond the idea of “atomic,” preimplemented, actions, and rather make them programmable while retaining high speed multi‐Gbps operation. To this purpose, we propose a domain‐specific HW architecture, called Packet Manipulation Processor (PMP), able to efficiently implement such actions. Both a PMP C++ instruction set simulator and a NetFPGA prototype have been developed. The performances of the PMP have been verified with three nontrivial use cases (tunneling, NAT, and ARP reply generation), showing that also in the worst case the throughput is well above 10 Gbps. 相似文献
140.
Marina Russo Paola Dugo Chiara Fanali Laura Dugo Mariosimone Zoccali Luigi Mondello Laura De Gara 《Food Analytical Methods》2018,11(10):2637-2644
Caffeine is the most widely studied psychoactive molecule in history due to its many pharmacological activities and a high number of biological and physiological effects. In literature, there is a great number of applications that describe extraction, identification, and quantification of caffeine in foods and beverages. For this purpose, an extraction step is followed by an analytical technique for the identification and quantification of caffeine. This work proposes an innovative method in which sample preparation, separation, and detection steps are unified in a single step. To the best of our knowledge, this is the first report on the determination of caffeine in coffee, tea, and cocoa by means of an online extraction coupled to a liquid chromatographic system equipped with a photodiode array detector. The developed methodology was validated in terms of sensitivity, detection limits, accuracy, and precision. The advantages of this technique are (i) a significant reduction of analysis time (more than 70%) and of solvents used (the extraction step is integrated in the chromatographic analysis), (ii) the whole procedure is thus completely automated drastically reducing possible operator errors to occur, and (iii) easily realized by using a conventional monodimensional liquid chromatography system. 相似文献