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71.
Rafael Vargas‐Bernal Carlos A. De la Cruz Blas Cristina Gómez‐Polo 《International Journal of Circuit Theory and Applications》2015,43(12):2072-2080
Nowadays, the design of magneto‐impedance (MI) sensors requires the development of lumped circuit models that can be simulated through equivalent impedance circuits relied on Bessel functions. A new impedance model based on Senani's equivalent using the zeros of Bessel functions is developed in this paper. The model allows to describe the impedance as a transfer function that can be easily synthesized by means of current conveyor circuits and passive elements. The mathematical representation was verified under simulation of transfer functions involving different number of poles and zeros. Moreover, the model has been verified using SPICE simulations and measurement results from a fabricated prototype demonstrating its scope and validity. Finally, a study of finite tracking errors of CCIIs used in the implementation of magneto‐impedance sensor has been realized. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
72.
Bor‐Sen Chiou Diana Valenzuela‐Medina Mark Wechsler Cristina Bilbao‐Sainz Artur K. Klamczynski Tina G. Williams Delilah F. Wood Greg M. Glenn William J. Orts 《应用聚合物科学杂志》2015,132(10)
Torrefied almond shells and wood chips were incorporated into polypropylene as fillers to produce torrefied biomass‐polymer composites. The composites were prepared by extrusion and injection molding. Response surface methodology was used to examine the effects of filler concentration, filler size, and lignin factor (relative lignin to cellulose concentration) on the material properties of the composites. The heat distortion temperatures, thermal properties, and tensile properties of the composites were characterized by thermomechanical analysis, differential scanning calorimetry, and tensile tests, respectively. The torrefied biomass composites had heat distortion temperatures of 8–24°C higher than that of neat polypropylene. This was due to the torrefied biomass restricting mobility of polypropylene chains, leading to higher temperatures for deformation. The incorporation of torrefied biomass generally resulted in an increase in glass transition temperature, but did not affect melting temperature. Also, the composites had lower tensile strength and elongation at break values than those of neat polypropylene, indicating weak adhesion between torrefied biomass and polypropylene. However, scanning electron microscopy results did indicate some adhesion between torrefied biomass and polypropylene. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41582. 相似文献
73.
Polycarbonate‐based composites reinforced by in situ polytetrafluoroethylene fibrillation: Preparation,thermal and rheological behavior 下载免费PDF全文
Diego Antonioli Katia Sparnacci Michele Laus Luca Boarino Maria Cristina Righetti 《应用聚合物科学杂志》2015,132(32)
Fibrillar reinforced composites of polytetrafluoroethylene (PTFE) and polycarbonate (PC) were prepared by in situ fibrillation of PTFE into PC matrix using twin screw extruder. Different samples were obtained by varying the relative ratio between PC and PTFE. The rheological properties of the PC/PTFE composites were found to depend on concentration of the PTFE fibrils. The melt strength analysis in nonisothermal conditions was also studied. The increase in force and decrease in drawability with increasing the PTFE content are associated with the PTFE fibrils formed in situ during the thermomechanical process in twin screw extruder. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42401. 相似文献
74.
Tânia F.C.V. Silva M. Elisabete F. Silva A. Cristina Cunha-Queda Amélia Fonseca Isabel Saraiva M.A. Sousa C. Gonçalves M.F. Alpendurada Rui A.R. Boaventura Vítor J.P. Vilar 《Water research》2013
A multistage treatment system, at a scale close to the industrial, was designed for the treatment of a mature raw landfill leachate, including: a) an activated sludge biological oxidation (ASBO), under aerobic and anoxic conditions; b) a solar photo-Fenton process, enhancing the bio-treated leachate biodegradability, with and without sludge removal after acidification; and c) a final polishing step, with further ASBO. 相似文献
75.
Maternal Flaxseed Oil During Lactation Enhances Bone Development in Male Rat Pups 总被引:1,自引:0,他引:1 下载免费PDF全文
Aline D’Avila Pereira Danielle Cavalcante Ribeiro Fernanda Carvalho de Santana Aline de Sousa dos Santos Jorge Mancini-Filho Celly Cristina Alves do Nascimento-Saba Luis Guillermo Coca Velarde Carlos Alberto Soares da Costa Gilson Teles Boaventura 《Lipids》2016,51(8):923-929
Flaxseed oil is an alpha linolenic acid source important in the growth and body development stage; furthermore, this acid acts on adipose tissue and bone health. The aim of this study was to evaluate body composition, fatty acid composition, hormone profile, retroperitoneal adipocyte area and femur structure of pups at weaning, whose mothers were fed a diet containing flaxseed oil during lactation. After birth, pups were randomly assigned: control (C, n = 12) and flaxseed oil (FO, n = 12), rats whose mothers were treated with diet containing soybean or flaxseed oil. At 21 days, the pups were weaned and body mass, length, body composition, biochemical parameter, leptin, osteoprotegerin, osteocalcin, fatty acids composition, intra‐abdominal fat mass and femur structure were analyzed. FO showed (p < 0.05): higher body mass (+12 %) and length (+9 %); body fat mass (g, +45 %); bone mineral density (+8 %), bone mineral content (+55 %) and bone area (+35 %), osteocalcin (+173 %) and osteoprotegerin (+183 %). Arachidonic acid was lower (p < 0.0001), alpha‐linolenic and eicosapentaenoic were higher (p < 0.0001). Intra‐abdominal fat mass was higher (+25 %), however, the retroperitoneal adipocytes area was lower (?44 %). Femur mass (+10 %), distance between epiphyses (+4 %) and bone mineral density (+13 %) were higher. The study demonstrates that adequate flaxseed oil content during a lactation diet plays an important role in the development of pups. 相似文献
76.
77.
Nana Achile Alomayri Thamer Salman Venyite Paul Kaze Rodrigue C. Assaedi Hasan Suliman Nobouassia Christelle Bewa Sontia Jordan Valdès Metekong Ngouné Jean Kamseu Elie Leonelli Cristina 《SILICON》2022,14(1):263-274
Silicon - The synthesis, mechanical behaviour, and microstructure of metakaolin-based geopolymer mortar reinforced with quartz sand are presented in this investigation. Fine sand (quartz sand)... 相似文献
78.
Cristina Cornaro Simona Bartocci Davide Musella Cecilia Strati Alessandro Lanuti Simone Mastroianni Stefano Penna Andrea Guidobaldi Fabrizio Giordano Eleonora Petrolati Thomas M. Brown Andrea Reale Aldo Di Carlo 《Progress in Photovoltaics: Research and Applications》2015,23(2):215-225
New generation photovoltaic (PV) devices such as polymer and dye sensitized solar cells (DSC) have now reached a more mature stage of development, and among their various applications, building integrated PVs seems to have the most promising future, especially for DSC devices. This new generation technology has attracted an increasing interest because of its low cost due to the use of cheap printable materials and simple manufacturing techniques, easy production, and relatively high efficiency. As for the more consolidated PV technologies, DSCs need to be tested in real operating conditions and their performance compared with other PV technologies to put into evidence the real potential. This work presents the results of a 3 months outdoor monitoring activity performed on a DSC mini‐panel made by the Dyepower Consortium, positioned on a south oriented vertical plane together with a double junction amorphous silicon (a‐Si) device and a multi‐crystalline silicon (m‐Si) device at the ESTER station of the University of Rome Tor Vergata. Good performance of the DSC mini‐panel has been observed for this particular configuration, where the DSC energy production compares favorably with that of a‐Si and m‐Si especially at high solar angles of incidence confirming the suitability of this technology for the integration into building facades. This assumption is confirmed by the energy produced per nominal watt‐peak for the duration of the measurement campaign by the DSC that is 12% higher than that by a‐Si and only 3% lower than that by m‐Si for these operating conditions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
79.
Roberta Gentilini Sabrina Bozzini Fabiola Munarin Paola Petrini Livia Visai Maria Cristina Tanzi 《应用聚合物科学杂志》2014,131(2)
Extraction, purification, and gel preparation of Aloe Vera pectin and the evaluation of the biocompatibility of the pectin gels were studied, considering as end use as implantable materials for regenerative medicine. A. Vera was chosen as source of pectin, as this pectin was described to possess high molecular weight and a low degree of esterification. As the properties of pectins are strictly dependent upon the extraction methods in combination with the natural source, the extraction method was modified in order to optimize the yield of the final product, its purity, the duration of the process and the selection of non‐toxic chemical reagents. Changing the experimental conditions resulted in four different extraction processes and products with different physical and chemical characteristics. The optimal extraction resulted to be the process: with enzimatic deactivation by microwave and the use of sodium citrate as chelating agent the molecular weight of the pectin extracted was estimated to be 118 kDa and the 2.93% esterification degree. Cytocompatibility of pectin gels, prepared by ionotropic gelation, showing an improved cell adhesion if compared to commercial pectin. The results suggest that the extracted A. Vera pectins possess interesting properties to be exploited for the production of mechanically stable gels by ionotropic gelation and high rhamnose content matrices for application in regenerative medicine. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39760. 相似文献
80.
The isothermal crystallization kinetics of PLA/fluoromica nanocomposites was studied. Three types of synthetic mica at three concentrations (2.5, 5.0, and 7.5 wt % mica) were used and the effect of these micas on the crystallization and thermal properties of PLA was investigated by differential scanning calorimetry (DSC). The Avrami and Hoffman‐Weeks equations were used to describe the isothermal crystallization kinetics and melting behavior. Addition of these micas to the PLA matrix increased the crystallization rate, and this effect depended on the mica type and concentration. While the nonmodified Somasif ME‐100 exerted the smallest effect, the effect observed for the organically modified Somasif MPE was the most pronounced. The lower half‐time of crystallization t1/2 was around 3 min for the PLA/Somasif MPE nanocomposites containing 7.5 wt % of filler at 90°C, which is about 16 min below that found for neat PLA. The equilibrium melting temperature ( ) of PLA were estimated for these systems, showing an increase in the composites and an increase with increasing loading, except for PLA/Somasif MPE, in which the increase of the mica content decreased about 5°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40322. 相似文献