Deformed Phase Space in Cosmology and Black Holes

It is well known that one way to study canonical quantum cosmology is through the Wheeler DeWitt (WDW) equation where the quantization is performed on the minisuperspace variables. The original ideas of a deformed minisuperspace were done in connection with noncommutative cosmology, by introducing a deformation into the minisuperspace in order to incorporate an effective noncommutativity. Therefore, studying solutions to Cosmological models through the WDW equation with deformed phase space could be interpreted as studying quantum effects to Cosmology. In this chapter, we make an analysis of scalar field cosmology and conclude that under a phase space transformation and imposed restriction, the effective cosmological constant is positive. On the other hand, obtaining the wave equation for the noncommutativity Kantowski-Sachs model, we are able to derive a modified noncommutative version of the entropy. To that purpose, the Feynman-Hibbs procedure is considered in order to calculate the partition function of the system

Influence of pork liver drying on ferrochelatase activity for zinc protoporphyrin formation

Pork liver contains an endogenous enzyme, ferrochelatase (FeCH), which catalyses the formation of zinc protoporphyrin (ZnPP), a natural pigment of great interest for the meat industry. The aim of this study was to analyse the effect of pork liver drying (from −10 to 70 °C), as a stabilisation method, on the FeCH activity (EA) and the apparent concentration (ECapp). Drying temperatures close to room conditions (from 10 to 20 °C) allowed to preserve well the ECapp, while the EA was slightly lower (−15.2%) than in raw liver. However, when drying was conducted at extreme conditions (−10 and 70 °C), the lowest values of ECapp and EA were manifested. Therefore, the drying process at moderate temperatures close to room conditions (10 - 20 °C) was considered to be an effective method for FeCH preservation since it was possible to stabilise the liver and the loss of FeCH activity was minimised.info:eu-repo/semantics/publishedVersio

Recovery of different waste vegetable oils for biodiesel production: a pilot experience in Bahia State, Brazil

In Brazil, and mainly in the State of Bahia, crude vegetable oils are widely used in the preparation of food. Street stalls, restaurants and canteens make a great use of palm oil and soybean oil. There is also some use of castor oil, which is widely cultivated in the Sert\ue3o Region (within the State of Bahia), and widely applied in industry. This massive use in food preparation leads to a huge amount of waste oil of different types, which needs either to be properly disposed of, or recovered. At the Laboratorio Energia e Gas-LEN (Energy & Gas lab.) of the Universidade Federal da Bahia, a cycle of experiments were carried out to evaluate the recovery of waste oils for biodiesel production. The experiences were carried out on a laboratory scale and, in a semi-industrial pilot plant using waste oils of different qualities. In the transesterification process, applied waste vegetable oils were reacted with methanol with the support of a basic catalyst, such as NaOH or KOH. The conversion rate settled at between 81-85% (in weight). The most suitable molar ratio of waste oils to alcohol was 1:6, and the amount of catalyst required was 0.5% (of the weight of the incoming oil), in the case of NaOH, and 1%, in case of KOH. The quality of the biodiesel produced was tested to determine the final product quality. The parameters analyzed were the acid value, kinematic viscosity, monoglycerides, diglycerides, triglycerides, free glycerine, total glycerine, clearness; the conversion yield of the process was also evaluated

Soldagem Por Atrito Com Pino Não Consumível De Aços Inoxidáveis Duplexa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Duplex stainless steels are successful in a variety of applications such as the food industry, petrochemical and plants for desalination of seawater, where high corrosion resistance and high mechanical strength are required. However, the beneficial microstructure may be change during fusion welding steps and it can compromise the performance of these materials. Friction stir welding is a solid state process avoiding typical problems concerning solidification such as solidification cracks, liquation and segregation of alloying elements. For superduplex stainless steels can avoid unbalanced proportions of ferrite and austenite, formation of secondary deleterious phases and grain growth of ferrite in the heat affected zone. Consolidated friction stir welded joints with full penetration of 6 mm thick were obtained for UNS S32101 and S32205 duplex and S32750 and S32760 superduplex stainless steels. The friction stir welds were submitted to tensile tests indicating an improvement of strength in welded joints showing increased of yield and tensile strength for all studied cases. Regarding the microstructural characterization, an outstanding gran refinement was observed in the welded joint achieving grain sizes as small as 1 μm. This refinement was associated with the combination of microstructural restoration mechanisms in the dual phase microstructure promoted by severe deformation associated with a high temperature during the welding process. © 2016, Universidade Federal de Uberlandia. All rights reserved.2115969CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP, Fundação de Amparo à Pesquisa do Estado de São PauloConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Induced Force Hovering of Spherical Robot by Under-Actuated Control of Dual Rotor

This chapter discusses the design and modelling of a spherical flying robot. The main objective is to control its hovering and omnidirectional mobility by controlling the air mass differential pressure between two asynchronous coaxial rotors that are aligned collinearly. The spherical robot design has embedded a gyroscopic mechanism of three rings that allow the rotors’ under-actuated mobility with 3DOF. The main objective of this study is to maintain the thrust force with nearly vertical direction. The change in pressure between rotors allows to vary the rotors’ tilt and pitch. The system uses special design propellers to improve the laminar air mass flux. A nonlinear fitting model automatically calibrates the rotors’ angular speed as a function of digital values. This model is the functional form that represents the reference input to control the rotors’ speed, validated by three types controllers: P, PI, and PID. The robot’s thrust and induced forces and flight mechanics are proposed and analysed. The simulation results show the feasibility of the approach

Information-theoretic criterion for the performance of single-photon avalanche photodiodes

A channel-capacity metric is introduced for assessing the performance of single-photon avalanche photodiodes (SPADs) when used as detectors in laser communication systems. This metric is employed to theoretically optimize, with respect to the device structure and operating voltage, the performance of SPADs with simple InP or In/sub 0.52/Al/sub 0.48/As-InP heterojunction multiplication regions. As the multiplication-region width increases, an increase is predicted in both the peak and the full-width at half-maximum of the channel capacity curve versus the normalized excess voltage. Calculations also show the existence of an optimal In/sub 0.52/Al/sub 0.48/As-InP heterojunction multiplication region that maximizes the peak channel capacity beyond that of InP

Ultrasound intensification of Ferrochelatase extraction from pork liver as a strategy to improve ZINC-protoporphyrin formation

[EN] The enzyme Ferrochelatase (FeCH), which is naturally present in pork liver, catalyses the formation of Zincprotoporphyrin (ZnPP), a natural pigment responsible for the typical color of dry-cured Italian Parma ham. The aim of this study was to evaluate the feasibility of using high power ultrasound in continuous and pulsed modes to intensify the extraction of the enzyme FeCH from pork liver. US application during FeCH extraction led to an improved enzymatic activity and further increase in the formation of ZnPP. The optimal condition tested was that of 1 min in continuous US application, in which time the enzymatic activity increased by 33.3 % compared to conventional extraction (30 min). Pulsed US application required 5 min treatments to observe a significant intensification effect. Therefore, ultrasound is a potentially feasible technique as it increases the catalytic activity of FeCH and saves time compared to the conventional extraction methodThe authors acknowledge the financial support from the "Ministerio de Economia y Competitividad (MINECO) and Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA)" in Spain (Project RTA2017-00024-C04-03). The authors acknowledge the contribution of the undergraduate student Jose V. Pedrero-Gonzalez to the experimental work.Abril-Gisbert, B.; Sanchez-Torres, E.; Bou, R.; Garcia-Perez, J.; Benedito Fort, JJ. (2021). Ultrasound intensification of Ferrochelatase extraction from pork liver as a strategy to improve ZINC-protoporphyrin formation. Ultrasonics Sonochemistry. 78:1-7. https://doi.org/10.1016/j.ultsonch.2021.105703S177

Water desorption isotherms of pork liver and thermodynamic properties

[EN] For the first time, the relationship between equilibrium moisture content and water activity is reported for the desorption process in pork liver. For that purpose, a standardized conductivity hygrometer was used at four different temperatures (0, 10, 30 and 50 degrees C) over a wide range of water activity (0.999-0.103). Five models frequently found in the literature (GAB, Oswin, Henderson, Hasley and Ratti) were considered for the purposes of describing the experimental desorption. The GAB model emerged as the best option (explained variance 96.6%) for the physical and mathematical description of the water desorption isotherms in pork liver. The computed isosteric heat, entropy and Gibbs energy illustrated the high water-sorbent affinity, because of a considerable availability of strong sorption sites at low moisture contents. The reported experimental desorption isotherms, and modeling results, are essentials for the optimal design of the drying process of pork liver, which is a necessary step for the further research addressing the extraction of the protein fraction from the dried product. Extraction and isolation of the protein fraction from pork liver could be considered a reasonable strategy considering the demand of protein materials and the high-environmental impact of the meat industry.The authors acknowledge the financial support from the "Ministerio de Economia y Competitividad (MINECO)" and "Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA)" in Spain (Project RTA 2017-00024-C04-03). Eduardo A. Sanchez-Torres acknowledges the FPU PhD contract (FPU18/01439) granted by the Spanish Ministry of Science, Innovation and Universities.Sanchez-Torres, E.; Abril-Gisbert, B.; Benedito Fort, JJ.; Bon Corbín, J.; Garcia-Perez, J. (2021). Water desorption isotherms of pork liver and thermodynamic properties. LWT - Food Science and Technology. 149:1-10. https://doi.org/10.1016/j.lwt.2021.11185711014

Detection Efficiencies and Generalized Breakdown Probabilities for Nanosecond-Gated Near Infrared Single-Photon Avalanche Photodiodes

A rigorous model is developed for determining single-photon quantum efficiency (SPQE) of single-photon avalanche photodiodes (SPADs) with simple or heterojunction multiplication regions. The analysis assumes nanosecond gated-mode operation of the SPADs and that band-to-band tunneling of carriers is the dominant source of dark current in the multiplication region. The model is then utilized to optimize the SPQE as a function of the applied voltage, for a given operating temperature and multiplication-region structure and material. The model can be applied to SPADs with In/sub 0.52/Al/sub 0.48/As or InP multiplication regions as well as In/sub 0.52/Al/sub 0.48/As--InP heterojunction multiplication regions for wavelengths of 1.3 and 1.55 /spl mu/m. The predictions show that the SPQE generally decreases with decreasing the multiplication-region thickness. Moreover, an InP multiplication region requires a lower breakdown electric field (and, hence, offers a higher SPQE) than that required by an In/sub 0.52/Al/sub 0.48/As layer of the same width. The model also shows that the fractional width of the In/sub 0.52/Al/sub 0.48/As layer in an In/sub 0.52/Al/sub 0.48/As--InP heterojunction multiplication region can be optimized to attain a maximum SPQE that is greater than that offered by an InP multiplication region. This effect becomes more pronounced in thin multiplication regions as a result of the increased significance of dead space