Estimation of deposit and spray distribution in hydro sensible paper and morning glory plant

Herbicides application success depends, besides product correct choice, the observation of environmental conditions and application quality. The work aimed to quantify the effects of surfactant addition in spraying solution, in natural and artificial targets, associated to different nozzle boom angles in relation to application offset, by using distinct evaluation methods. Two experiments were conducted at NuPAM-FCA/UNESP, Botucatu County, São Paulo State, constituted by ten treatments, in factorial scheme 2 × 5, corresponding to two spraying solutions conditions (absence or presence of Aterbane BRTM (0.25% v/v) adjuvant) and five angles of spray nozzle in relation to offset application (-30°, -15°, 90°, +15° and +30°). In Ipomea grandifolia leaves, the distribution and drops deposition of a tracer solution were evaluated by using scores visual and spectrophotometer process. In hydro sensible papers, volumetric medium diameter (VMD), density (cm2 ) and drops medium diameter, covered area (%) and application fees (L ha-1) were evaluated through e-SprinkleTM software. Aterbane BRTM (0.25% v/v) presence or absence, associated or no, to spray nozzles offset did not provide significant differences in I. grandifolia spray deposition. The use of artificial targets presented applicative technical limitations in relation to the use of natural ones as study matrix. Deposit and distribution variables esteem distinct behaviours, independent of target nature.

Estudo da combustão do óleo pirolítico de pneus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Métodos de debicagem: desenvolvimento e desempenho produtivo de poedeiras leves e semipesadas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Projeto de adaptação do sistema de injeção do túnel transônico para ensaios em bocais de foguete

In this work, the project of a new experimental facility to be installed at the Aerodynamics Division of the Institute of Aeronautics and Space is presented. This new facility will provide means to perform experimental campaigns to analyze the flow behavior at different rocket nozzle concepts using cold gas that will be obtained from a modification of the Pilot Transonic Wind Tunnel air system. The new installation will enable less expensive experiments in a more secure environment, since the cold gas experimental procedures do not demand fuel storage and burn and security procedures are much less severe. Furthermore, experiments can be carried with different types of sensors, commonly used in wind tunnel tests. Also, the optical access is facilitated enabling the use of optical techniques for the characterization of flow properties inside the nozzles, such as pressure and temperature sensitive painting. The full project design and the operation conditions will be showed, as also some technical considerations about the flor behavior in the facility

Ideologia sobre a mulher em pride and prejudice: uma análise dialógica do filme e do livro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Métodos de debicagem: desenvolvimento e desempenho produtivo de poedeiras leves e semipesadas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Projeto de adaptação do sistema de injeção do túnel transônico para ensaios em bocais de foguete

In this work, the project of a new experimental facility to be installed at the Aerodynamics Division of the Institute of Aeronautics and Space is presented. This new facility will provide means to perform experimental campaigns to analyze the flow behavior at different rocket nozzle concepts using cold gas that will be obtained from a modification of the Pilot Transonic Wind Tunnel air system. The new installation will enable less expensive experiments in a more secure environment, since the cold gas experimental procedures do not demand fuel storage and burn and security procedures are much less severe. Furthermore, experiments can be carried with different types of sensors, commonly used in wind tunnel tests. Also, the optical access is facilitated enabling the use of optical techniques for the characterization of flow properties inside the nozzles, such as pressure and temperature sensitive painting. The full project design and the operation conditions will be showed, as also some technical considerations about the flor behavior in the facility

Ideologia sobre a mulher em pride and prejudice: uma análise dialógica do filme e do livro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Six-element circuit for maximum power point tracking in photovoltaic-motor systems with variable-frequency drives

A low-cost circuit was developed for stable and efficient maximum power point (MPP) tracking in autonomous photo voltaic-motor systems with variable-frequency drives (VFDs). The circuit is made of two resistors, two capacitors, and two Zener diodes. Its input is the photovoltaic (PV) array voltage and its output feeds the proportional-integral-derivative (PID) controller usually integrated into, the drive. The steady-state frequency-voltage oscillations induced by the circuit were treated in a simplified mathematical model, which was validated by widely characterizing a PV-powered centrifugal pump. General procedures for circuit and controller tuning were recommended based on model equations. The tracking circuit presented here is widely applicable to PV-motor system with VFDs, offering an. efficient open-access technology of unique simplicity. Copyright (C) 2010 John Wiley & Sons, Ltd.

Quality characteristics and fertilizing ability of ram sperm subpopulations separated by partition in an aqueous two-phase system

Centrifugal countercurrent distribution (CCCD) in an aqueous two-phase system (TPS) is a resolute technique revealing sperm heterogeneity and for the estimation of the fertilizing potential of a given semen sample. However, separated sperm subpopulations have never been tested for their fertilizing ability yet. Here, we have compared sperm quality parameters and the fertilizing ability of sperm subpopulations separated by the CCCD process from ram semen samples maintained at 20 degrees C or cooled down to 5 degrees C. Total and progressive sperm motility was evaluated by computer-assisted analysis using a CASA system and membrane integrity was evaluated by flow cytometry by staining with CFDA/Pl. The capacitation state, staining with chlortetracycline, and apoptosis-related markers, such as phosphatidylserine (PS) translocation detected with Annexin V. and DNA damage detected by the TUNEL assay, were determined by fluorescence microscopy. Additionally, the fertilizing ability of the fractionated subpopulations was comparative assessed by zona binding assay (ZBA). CCCD analysis revealed that the number of spermatozoa displaying membrane and DNA alterations was higher in samples chilled at 5 degrees C than at 20 degrees C. which can be reflected in the displacement to the left of the CCCD profiles. The spermatozoa located in the central and right chambers (more hydrophobic) presented higher values (P<0.01) of membrane integrity, lower PS translocation (P<0.05) and DNA damage (P<0.001) than those in the left part of the profile, where apoptotic markers were significantly increased and the proportion of viable non-capacitated sperm was reduced. We have developed a new protocol to recover spermatozoa from the CCCD fractions and we proved that these differences were related with the fertilizing ability determined by ZBA, because we found that the number of spermatozoa attached per oocyte was significantly higher for spermatozoa recovered from the central and right chambers, in both types of samples. This is the first time, to our knowledge that sperm recovered from a two-phase partition procedure are used for fertilization assays. These results open up new possibilities for using specific subpopulations of sperm for artificial insemination or in vitro fertilization, not only regarding better sperm quality but also certain characteristics such as subpopulations enriched in spermatozoa bearing X or Y chromosome that we have already isolated or any other feature. (C) 2011 Elsevier B.V. All rights reserved.

TRANSVERSAL DISTRIBUTION COMPARISON OF SOLID FERTILIZERS APPLIED OVER ANNUAL CROPS

Centrifugal spreaders dominate the application of solid materials in agriculture offering expressive operational field capacity and extended range of applied rates. Field tests for characterization of theirperformance are conducted without any physical obstacles (such as the presence of plants) during the parabolic trajectory of the falling particles of fertilizer to the soil. The purpose of this study was to comparatively evaluate the transverse distribution of solid fertilizers applied on cropped corn, soybeans and cotton. Evaluations of the spreaders were designed according to ASAE S341.3/99 Standard. Tests consisted in aligning side by side collectors in-between the cropped rows and weighting the material deposited. The results showed that transverse distribution of solid fertilizers applied over the cotton and corn crops is affected by the crop height, interfering directly on the effective width of the spreader application, which was not observedin the soybean crop, once the fertilizer application is done when the crop was still below the collector's height. The results suggest that evaluation of effective width of the spreaders application need to be done under real crop environment.

Period adding cascades: Experiment and modeling in air bubbling

Period adding cascades have been observed experimentally/numerically in the dynamics of neurons and pancreatic cells, lasers, electric circuits, chemical reactions, oceanic internal waves, and also in air bubbling. We show that the period adding cascades appearing in bubbling from a nozzle submerged in a viscous liquid can be reproduced by a simple model, based on some hydrodynamical principles, dealing with the time evolution of two variables, bubble position and pressure of the air chamber, through a system of differential equations with a rule of detachment based on force balance. The model further reduces to an iterating one-dimensional map giving the pressures at the detachments, where time between bubbles come out as an observable of the dynamics. The model has not only good agreement with experimental data, but is also able to predict the influence of the main parameters involved, like the length of the hose connecting the air supplier with the needle, the needle radius and the needle length. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3695345]

Computational and experimental characterization of a low-cost piezoelectric valveless diaphragm pump

Flow pumps act as important devices in areas such as Bioengineering, Medicine, and Pharmacy, among other areas of Engineering, mainly for delivering liquids or gases at small-scale and precision flow rate quantities. Principles for pumping fluids based on piezoelectric actuators have been widely studied, since they allow the construction of pump systems for displacement of small fluid volumes with low power consumption. This work studies valveless piezoelectric diaphragm pumps for flow generation, which uses a piezoelectric ceramic (PZT) as actuator to move a membrane (diaphragm) up and down as a piston. The direction of the flow is guaranteed by valveless configuration based on a nozzle-diffuser system that privileges the flow in just one pumping direction. Most research efforts on development of valveless flow pump deal either with computational simulations based on simplified models or with simplified physical approaches based on analytical models. The main objective of this work is the study of a methodology to develop a low-cost valveless piezoelectric diaphragm flow pump using computational simulations, parametric study, prototype manufacturing, and experimental characterization. The parametric study has shown that the eccentricity of PZT layer and metal layer plays a key role in the performance of the pump.

Multi-Walled Carbon Nanotubes and Poly(lactic acid) Nanocomposite Fibrous Membranes Prepared by Solution Blow Spinning

Nanocomposite fibers based on multi-walled carbon nanotubes (MWCNT) and poly(lactic acid) (PLA) were prepared by solution blow spinning (SBS). Fiber morphology was characterized by scanning electron microscopy (SEM) and optical microscopy (OM). Electrical, thermal, surface and crystalline properties of the spun fibers were evaluated, respectively, by conductivity measurements (4-point probe), thermogravimetric analyses (TGA), differential scanning calorimetry (DSC), contact angle and X-ray diffraction (XRD). OM analysis of the spun mats showed a poor dispersion of MWCNT in the matrix, however dispersion in solution was increased during spinning where droplets of PLA in solution loaded with MWCNT were pulled by the pressure drop at the nozzle, producing PLA fibers filled with MWCNT. Good electrical conductivity and hydrophobicity can be achieved at low carbon nanotube contents. When only 1 wt% MWCNT was added to low-crystalline PLA, surface conductivity of the composites increased from 5 x 10(-8) to 0.46 S/cm. Addition of MWCNT can slightly influence the degree of crystallinity of PLA fibers as studied by XRD and DSC. Thermogravimetric analyses showed that MWCNT loading can decrease the onset degradation temperature of the composites which was attributed to the catalytic effect of metallic residues in MWCNT. Moreover, it was demonstrated that hydrophilicity slightly increased with an increase in MWCNT content. These results show that solution blow spinning can also be used to produce nanocomposite fibers with many potential applications such as in sensors and biosensors.

Influence of alloy microstructure on the microshear bond strength of basic alloys to a resin luting cement

The aim of this study was to evaluate the influence of microstructure and composition of basic alloys on their microshear bond strength (µSBS) to resin luting cement. The alloys used were: Supreme Cast-V (SC), Tilite Star (TS), Wiron 99 (W9), VeraBond II (VBII), VeraBond (VB), Remanium (RM) and IPS d.SIGN 30 (IPS). Five wax patterns (13mm in diameter and 4mm height) were invested, and cast in a centrifugal casting machine for each basic alloy. The specimens were embedded in resin, polished with a SiC paper and sandblasted. After cleaning the metal surfaces, six tygon tubes (0.5 mm height and 0.75 mm in diameter) were placed on each alloy surface, the resin cement (Panavia F) was inserted, and the excess was removed before light-curing. After storage (24 h/37°C), the specimens were subjected to µSBS testing (0.5 mm/min). The data were subjected to a one-way repeated measures analysis of variance and Turkey's test (α=0.05). After polishing, their microstructures were revealed with specific conditioners. The highest µSBS (mean/standard deviation in MPa) were observed in the alloys with dendritic structure, eutectic formation or precipitation: VB (30.6/1.7), TS (29.8/0.9), SC (30.6/1.7), with the exception of IPS (31.1/0.9) which showed high µSBS but no eutectic formation. The W9 (28.1/1.5), VBII (25.9/2.0) and RM (25.9/0.9) showed the lowest µSBS and no eutectic formation. It seems that alloys with eutectic formation provide the highest µSBS values when bonded to a light-cured resin luting cement.