Sorocaba - ICTS - Instituto de Ciência e Tecnologia

URI Permanente para esta coleçãohttps://hdl.handle.net/11449/253784

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Preface
(2022-01-01) Fernandes Fraceto, Leonardo ; Pereira de Carvalho, Hudson Wallace ; de Lima, Renata ; Ghoshal, Subhashis ; Santaella, Catherine ; Universidade Estadual Paulista (UNESP) ; Universidade de São Paulo (USP) ; Universidade de Sorocaba ; McGill University ; Aix-Marseille University
Enlightening Load Modeling by Means of Power Factor Decompositions
(2023-05-01) Paredes, Helmo K. Morales ; Arcadepani, Matheus Branco ; Moreira, Alexandre Candido ; Gonçalves, Flávio A. Serrão ; Pinhabel Marafão, Fernando ; Universidade Estadual Paulista (UNESP) ; Universidade Federal de Sergipe (UFS)
Considering the proliferation of power electronics applications and distributed energy resources, modern power grids are facing a significant increase in harmonic currents circulation and supply voltage deterioration, occasionally associated with small frequency variations. In such a context, the understanding of power phenomena in circuits with linear and non-linear loads under non-sinusoidal voltage conditions is nontrivial and still does not allow for an easy interpretation of harmonic sources, harmonic power flow or the identification of the parameters of a proper equivalent circuit. The main challenge is to develop modern theoretical approaches for load characterization, modeling, and parameter estimation so that new techniques can be formulated to provide adequate guiding for the analysis, compensation, revenue metering, accountability and other applications of power systems. Thus, based on the Conservative Power Theory (CPT) and further decomposition of its apparent power and power factor definitions, this paper proposes a novel methodology for estimating equivalent parameters and for proposing proper equivalent circuits capable of representing/modeling the main characteristics of single-phase generic loads (black boxes) and the related power phenomena in terms of passive dipoles (linear loads) or of harmonic voltage/current sources and their intrinsic transimpedances/transadmittances (non-linear loads). Simulation and experimental results were depicted to support and validate the proposed approach, showing that it might be a powerful modeling technique to represent generic loads in a modern power grid scenario, while being used for complex applications such as reactive power compensation or accountability in circuits with nonlinear loads and distorted voltages.
Pre-emergence herbicidal efficiency and uptake of atrazine-loaded zein nanoparticles: a sustainable alternative to weed control
(2023-01-01) Carvalho, Lucas Bragança ; Godoy, Isabela Silva ; Preisler, Ana Cristina ; de Freitas Proença, Patrícia Luiza ; Saraiva-Santos, Telma ; Verri, Waldiceu Aparecido ; Oliveira, Halley Caixeta ; Dalazen, Giliardi ; Fraceto, Leonardo Fernandes ; Universidade Estadual Paulista (UNESP) ; Universidade Estadual de Londrina (UEL)
In this study, we describe the development of zein nanoparticles associated with the herbicide atrazine and evaluate the pre-emergence activity of this formulation against a target (Brassica juncea) and a non-target (Zea mays) plant, as well as its soil mobility and uptake/transport in the tissues of Bidens pilosa plants. The proposed nanoformulation showed good colloidal stability, with nanoparticles of spherical shape, sizes between 130 and 170 nm, and an encapsulation efficiency of the active ingredient above 90%. The nanoencapsulation provided greater herbicide effectiveness against B. juncea, even at a dose 80 times lower than the recommended, without posing toxicity to the crop species. The monitoring of FITC-labeled nanoparticles indicated that the nanostructures were captured and accumulated in B. pilosa and Z. mays roots, but were poorly transported to the shoot. In addition, atrazine nanoencapsulation did not increase the mobility of the herbicide in the soil compared to the conventional formulation, remaining at the upper soil fractions, where the seed bank is located. Thus, these findings highlight the potential of this nanoformulation as an alternative for weed control.
Nanocomposite hydrogels 3D printed for application in water remediation
(2023-06-01) Baigorria, E. ; Souza dos Santos, S. ; de Moura, M. R. ; Fraceto, L. F. ; Universidade Estadual Paulista (UNESP) ; CONICET - Universidad Nacional de Mar Del Plata (UNMdP)
Three-dimensional (3D) printing of bioinks for the development of nanocomposite hybrid adsorbent hydrogels was performed. Sodium alginate (SA) matrix hydrogels and bentonite clay (SA-B) nanocomposite hydrogels were synthesized for this purpose. The bioinks used were characterized rheologically and the devices obtained were characterized physicochemically and morphologically. The efficiency of the hydrogels in the adsorption of the pesticide paraquat (PQ) was also studied. The results revealed the efficient formation of hybrid hydrogels and that the presence of clay in the biopolymer matrix improved the rheological, mechanical, thermal, and porous properties of the SA-B hydrogels. Both the SA-B30 bioink and corresponding 3D-printed device were found to be the best systems for use. PQ adsorption tests showed equilibrium adsorption capacities of 1.16, 1.33, 1.45, 2.10, 2.29, and 1.64 mg/g for SA, SA-B5, SA-B10, SA-B20, SA-B30, and SA-B50, respectively. Adsorption was exothermic and spontaneous in nature, involving physisorption processes. In addition, it exhibited a correlation mainly with the Freundlich isotherm model and the pseudo-first-order kinetic model used for nanocomposite devices. The SA-B30 hydrogel exhibited the best PQ adsorption performance. Recovery and reusability of the devices were achieved at least six times. This indicates that the synthesized eco-friendly, biodegradable, and low-cost materials can contribute to the circular economy. Thus, the developed adsorbent materials significantly contribute to ensuring that water is safe for human consumption.
The Effect of PEO Treatment in a Ta-Rich Electrolyte on the Surface and Corrosion Properties of Low-Carbon Steel for Potential Use as a Biomedical Material
(2023-03-01) Marcuz, Nádia ; Ribeiro, Rafael Parra ; Rangel, Elidiane Cipriano ; da Cruz, Nilson Cristino ; Correa, Diego Rafael Nespeque ; Wilson Roberto Ribeiro de Camargo ; Universidade Estadual Paulista (UNESP)
Fe-based materials have extensive applications in the building and automobile industries due to their excellent mechanical properties and low cost. However, their biomedical employment is restricted by the corrosion propensity when in contact with bodily fluids. In this study, single-step Plasma Electrolytic Oxidation, PEO, treatment in Ta-rich electrolyte was used, for the first time, to improve the corrosion resistance of low-carbon steel SAE 1020 for possible use as device implants. The effect of the applied voltage on the chemical and phase composition, topography, wettability, roughness, and corrosion properties were addressed. The results indicated that the Fe-based oxide coatings had a rough and hydrophilic surface, increasing the Ta content with the applied potential. The phase composition of the coatings was mainly composed of hematite (Fe2O3), with the Fourier-transform Infrared Spectroscopy, FTIR, spectrums indicating the presence of some absorbed water and organic molecules. The corrosion resistance of the PEO-treated samples was better than the substrate against saline solution (0.9% NaCl) due to the Fe2O3 growth decorated with Ta particles, especially the sample treated at 200 V. The results state that Ta-enriched Fe-based oxide coatings could significantly improve the applicability of low-carbon steel SAE 1020 as a low-cost biomaterial, particularly for medical devices.
Acaricides containing zein nanoparticles: A tool for a lower impact control of the cattle tick Rhipicephalus microplus
(2023-06-01) Figueiredo, Amanda ; Anholeto, Luís Adriano ; Cola, Diego Faria ; Fantatto, Rafaela Regina ; Gainza, Yousmel Alemán ; dos Santos, Isabella Barbosa ; Viçozzi, Gabriel Pedroso ; Ávila, Daiana Silva ; Fraceto, Leonardo Fernandes ; Chagas, Ana Carolina de Souza ; Universidade Estadual Paulista (UNESP) ; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) ; Federal University of Pampa
Nanoformulations containing zein nanoparticles (ZN) can promote the stability and protection of molecules with acaricidal activity. The present study sought to develop nanoformulations with ZN associated with cypermethrin (CYPE) + chlorpyrifos (CHLO) + a plant compound (citral, menthol or limonene), characterize them, and verify their efficacy against Rhipicephalus microplus ticks. Additionally, we aimed to assess its safety in nontarget nematodes found in soil at a site subjected to contamination by acaricides. The nanoformulations were characterized by dynamic light scattering and nanoparticle tracking analysis. Nanoformulations 1 (ZN+CYPE+CHLO+citral), 2 (ZN+CYPE+CHLO+menthol), and 3 (ZN+CYPE+CHLO+limonene) were measured for diameter, polydispersion, zeta potential, concentration, and encapsulation efficiency. Nanoformulations 1, 2, and 3 were evaluated in a range from 0.004 to 0.466 mg/mL on R. microplus larvae and caused mortality > 80% at concentrations above 0.029 mg/mL. The commercial acaricide Colosso® (CYPE 15 g + CHLO 25 g + citronellal 1 g) was evaluated also from 0.004 to 0.512 mg/mL and resulted in 71.9% larval mortality at 0.064 mg/mL. Formulations 1, 2, and 3 at 0.466 mg/mL showed acaricidal efficacy of 50.2%, 40.5%, and 60.1% on engorged females, respectively, while Colosso® at 0.512 mg/mL obtained only 39.4%. The nanoformulations exhibited long residual period of activity and lower toxicity to nontarget nematodes. ZN was able to protect the active compounds against degradation during the storage period. Thus, ZN can be an alternative for the development of new acaricidal formulations using lower concentrations of active compounds.
Antimicrobial behavior of titanium coating with chlorhexidine-doped thin film exposed to a biofilm supplemented with nicotine
(2023-01-01) Matos, Adaias Oliveira ; Rangel, Elidiane Cipriano ; Barão, Valentim Adelino Ricardo ; Gregory, Richard Lee ; University of Detroit Mercy ; Universidade Estadual de Campinas (UNICAMP) ; Indiana University School of Dentistry ; Universidade Estadual Paulista (UNESP)
Because nicotine upregulates the growth of most oral bacteria, this in vitro study investigated the antimicrobial effect of chlorhexidine-doped thin film on commercially pure titanium against Fusobacterium nucleatum (F. nucleatum) biofilm supplemented with different concentrations of nicotine (0, 1, and 2 mg/mL). Biofilms were formed on a chlorhexidine-doped thin film on commercially-pure-titanium discs and compared to the control groups. Biofilm viability, total biofilm growth using a spectrophotometer, extracellular polysaccharide content, and pH variations were assessed as dependent variables. Data were submitted to ANOVA and Tukey honest significant difference tests (α=0.05). F. nucleatum biofilm growth was inhibited when exposed to chlorhexidine-doped thin film (p<0.05). Biofilm supplemented with nicotine did not impact the synthesis of EPS on the same type of treatment (p>0.05). The pH values were significantly increased with the increase of nicotine concentration (p<0.05). Chlorhexidine-doped thin film was effective in reducing F. nucleatum biofilm supplemented with nicotine.
Encapsulated plant growth regulators and associative microorganisms: Nature-based solutions to mitigate the effects of climate change on plants
(2023-06-01) Campos, Estefânia V.R. ; Pereira, Anderson do E.S. ; Aleksieienko, Ivan ; do Carmo, Giovanna C. ; Gohari, Gholamreza ; Santaella, Catherine ; Fraceto, Leonardo F. ; Oliveira, Halley C. ; Universidade Estadual Paulista (UNESP) ; B.Nano Soluções Tecnológicas Ltda ; Microbial Ecology of the Rhizosphere ; Universidade Estadual de Londrina (UEL) ; University of Maragheh
Over the past decades, the atmospheric CO2 concentration and global average temperature have been increasing, and this trend is projected to soon become more severe. This scenario of climate change intensifies abiotic stress factors (such as drought, flooding, salinity, and ultraviolet radiation) that threaten forest and associated ecosystems as well as crop production. These factors can negatively affect plant growth and development with a consequent reduction in plant biomass accumulation and yield, in addition to increasing plant susceptibility to biotic stresses. Recently, biostimulants have become a hotspot as an effective and sustainable alternative to alleviate the negative effects of stresses on plants. However, the majority of biostimulants have poor stability under environmental conditions, which leads to premature degradation, shortening their biological activity. To solve these bottlenecks, micro- and nano-based formulations containing biostimulant molecules and/or microorganisms are gaining attention, as they demonstrate several advantages over their conventional formulations. In this review, we focus on the encapsulation of plant growth regulators and plant associative microorganisms as a strategy to boost their application for plant protection against abiotic stresses. We also address the potential limitations and challenges faced for the implementation of this technology, as well as possibilities regarding future research.
Preface
(2020-01-01) Fraceto, Leonardo F. ; de Castro, Vera Lucia S. S. ; Grillo, Renato ; Ávila, Daiana ; Oliveira, Halley Caixeta ; Lima, Renata ; Universidade Estadual Paulista (UNESP) ; Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) ; Federal University of Pampa ; Universidade Estadual de Londrina (UEL) ; Sorocaba University
A Tribological Investigation of the Titanium Oxide and Calcium Phosphate Coating Electrochemical Deposited on Titanium
(2023-02-01) Santos, Adriana ; Teixeira, Jean ; Fonzar, Carlos ; Rangel, Elidiane ; Cruz, Nilson ; Lisboa-Filho, Paulo Noronha ; Universidade Estadual Paulista (UNESP)
Titanium (Ti) and its alloys are widely used in biomedical applications due to their excellent mechanical properties and biocompatibility. However, they are a concern due to the possibility of cytotoxic effects coming from the degradation products. This degradation occurs by the combined action of corrosion and mechanical wear of these materials, which are released in the biological environment by the biomaterial implanted. The present article aims to investigate a new route to improve electrochemical and tribological performance with surface modification. Regarding the deposition of a protective layer on the surface, it consists of titanium oxide (TiO2) and calcium phosphate (CaP). Both coatings were performed by chronoamperometric methods with titanium oxidation at 1 V and calcium phosphate reduction at −1.5 V. The corrosion and tribocorrosion tests demonstrated the effective combination of TiO2 and CaP layer to protect the Ti substrate. Furthermore, this coating combination reduced corrosion degradation and mechanical wear in PBS, simulating a physiological environment. Additionally, it was observed that this combination of coating decreased the dissipated energy, and consequently, the wear decreased during sliding tests. All these findings indicate the protective behavior of the TiO2 and CaP layer during the tribocorrosion tests.
UTBB FD-SOI MOSFET with SELBOX in DTMOS configuration
(2022-12-31) Da Silva, Jeveson Cardoso ; Martins, Everson ; Junior, Nilton Graziono ; De Andrade, Maria Glória Caño ; Universidade Estadual Paulista (UNESP) ; Universidade Federal de Goiás (UFG)
For the first time, Ultra-Thin Body and Buried Oxide Fully Depleted Silicon-On-Insulator (UTBB FDSOI) n-channel with Dynamic Threshold MOS configuration (DTMOS) using the SELBOX (Selective Buried OXide) sub-strate was analyzed. The drain and substrate current, transcon-ductance (gm) and Subthreshold Slope (SS) ware compared in the DTMOS mode and the standard biasing configuration for different gap width (WGAP) of SELBOX. Additionally, the out-put conductance and the transconductance gain also studied through numerical simulations. The results indicate that the SELBOX structure in DTMOS mode is competitive candidates for analog applications.
A Novel Methodology to Estimate Probability Density Function of Voltage Sag Duration and Failure Rates on Power Distribution Systems
(2023-01-01) Cebrian, Juan C. ; Giacomini, Jairo ; Carneiro, Carlos A. ; Silva, Gabriela B. ; Morales-Paredes, Helmo K. ; Universidade Estadual Paulista (UNESP)
Voltage sags and power interruptions are important power quality problems that affect sensitive customers, mainly because they cause annual massive economical losses to the industrial sector as a result of unexpected production process disruptions. In this sense, to propose corrective and preventive measures and improve the power quality of the distribution systems, stochastic methodologies have been proposed in the literature to estimate annual voltage sags and power interruptions. However, these methodologies, generally, use typical cumulative distribution functions of voltage sag duration (PSgD), which may not reflect the real estate of the network under study. To solve this constraint, this paper proposes a novel methodology to estimate a proper PSgD considering information of the distribution network (i.e., topology and coordination schemes of the protection system) and the stochastic behaviors of short-circuits that can affect the distribution system. Moreover, the proposed methodology allows estimating permanent failure rates and average repair time considering known or expected values of reliability indicators. The results show that this proposed methodology is capable to adapt from an initial PSgD curve to another one with fidelity, in order to achieve real values of expected annual power interruptions.
Sensors Applied to Bearing Fault Detection in Three-Phase Induction Motors†
(2021-01-01) Lucas, Guilherme Beraldi ; de Castro, Bruno Albuquerque ; Serni, Paulo José Amaral ; Riehl, Rudolf Ribeiro ; Andreoli, André Luiz ; Universidade Estadual Paulista (UNESP)
Three-Phase Induction Motors (TIMs) are widely applied in industries. Therefore, there is a need to reduce operational and maintenance costs since their stoppages can impair production lines and lead to financial losses. Among all the TIM components, bearings are crucial in the machine operation once they couple rotor to the motor frame. Furthermore, they are constantly subjected to friction and mechanical wearing. Consequently, they represent around 41% of the motor fault, according to IEEE. In this context, several studies have sought to develop monitoring systems based on different types of sensors. Therefore, considering the high demand, this article aims to present the state of the art of the past five years concerning the sensing techniques based on current, vibration, and infra-red analysis, which are characterized as promising tools to perform bearing fault detection. The current and vibration analysis are powerful tools to assess damages in the inner race, outer race, cages, and rolling elements of the bearings. These sensing techniques use current sensors like hall effect-based, Rogowski coils, and current transformers, or vibration sensors such as accelerometers. The effectiveness of these techniques is due to the previously developed models, which relate the current and vibration frequencies to the origin of the fault. Therefore, this article also presents the bearing fault mathematical modeling for these techniques. The infra-red technique is based on heat emission, and several image processing techniques were developed to optimize bearing fault detection, which is presented in this review. Finally, this work is a contribution to pushing the frontiers of the bearing fault diagnosis area.
Repellent active ingredients encapsulated in polymeric nanoparticles: potential alternative formulations to control arboviruses
(2022-12-01) Abrantes, Daniele Carvalho ; Rogerio, Carolina Barbara ; Campos, Estefânia Vangelie Ramos ; Germano-Costa, Tais ; Vigato, Aryane Alves ; Machado, Ian Pompermeyer ; Sepulveda, Anderson Ferreira ; Lima, Renata ; de Araujo, Daniele Ribeiro ; Fraceto, Leonardo Fernandes ; Universidade Estadual Paulista (UNESP) ; University of Sorocaba ; Federal University of ABC
Dengue, yellow fever, Chinkungunya, Zika virus, and West Nile fever have infected millions and killed a considerable number of humans since their emergence. These arboviruses are transmitted by mosquito bites and topical chemical repellents are the most commonly used method to protect against vector arthropod species. This study aimed to develop a new generation of repellent formulations to promote improved arboviruses transmission control. A repellent system based on polycaprolactone (PCL)-polymeric nanoparticles was developed for the dual encapsulation of IR3535 and geraniol and further incorporation into a thermosensitive hydrogel. The physicochemical and morphological parameters of the prepared formulations were evaluated by dynamic light scattering (DLS), nano tracking analysis (NTA), atomic force microscopy (AFM). In vitro release mechanisms and permeation performance were evaluated before and after nanoparticles incorporation into the hydrogels. FTIR analysis was performed to evaluate the effect of formulation epidermal contact. Potential cytotoxicity was evaluated using the MTT reduction test and disc diffusion methods. The nanoparticle formulations were stable over 120 days with encapsulation efficiency (EE) of 60% and 99% for IR3535 and geraniol, respectively. AFM analysis revealed a spherical nanoparticle morphology. After 24 h, 7 ± 0.1% and 83 ± 2% of the GRL and IR3535, respectively, were released while the same formulation incorporated in poloxamer 407 hydrogel released 11 ± 0.9% and 29 ± 3% of the loaded GRL and IR3535, respectively. GRL permeation from PCL nanoparticles and PCL nanoparticles in the hydrogel showed similar profiles, while IR3535 permeation was modulated by formulation compositions. Differences in IR3535 permeated amounts were higher for PCL nanoparticles in the hydrogels (36.9 ± 1.1 mg/cm2) compared to the IR3535-PCL nanoparticles (29.2 ± 1.5 mg/cm2). However, both active permeation concentrations were low at 24 h, indicating that the formulations (PCL nanoparticles and PCL in hydrogel) controlled the bioactive percutaneous absorption. Minor changes in the stratum corneum (SC) caused by interaction with the formulations may not represent a consumer safety risk. The cytotoxicity results presented herein indicate the carrier systems based on poly-epsilon caprolactone (PCL) exhibited a reduced toxic effect when compared to emulsions, opening perspectives for these systems to be used as a tool to prolong protection times with lower active repellent concentrations.
Towards technical and economic feasibility of power quality compensators
(2023-03-01) Conrado, Bruna R.P. ; de Souza, Wesley A. ; Liberado, Eduardo V. ; Paredes, Helmo K.M. ; Brandao, Danilo I. ; Moreira, Alexandre C. ; Universidade Federal de Minas Gerais (UFMG) ; Federal University of Technology - Parana ; Universidade Estadual Paulista (UNESP)
In industrial grids, equipment lifetime is reduced, and power losses are increased due to typical issues caused by low power quality indices, such as insulation failure, overheating, mechanical oscillation, audible noise, high currents in the neutral conductor, harmonic resonance, and malfunctioning of power electronics converters and protections. These drawbacks can be mitigated by adopting power quality enhancement technologies known as compensators, such as passive power filters, static reactive compensators, and active power filters. However, the most appropriate compensation system must assure power quality indices within limits established by standards, which characterize its technical feasibility and is economically feasible. Therefore, this paper proposes a method to perform a feasibility analysis of power quality improvement projects considering both technical and economic aspects. The effectiveness of the proposed method has been verified by different case studies assessing real industrial operating conditions. The results show that the proposed methodology is robust and can select the best compensation solution under different grid conditions.
Availability of Metribuzin-Loaded Polymeric Nanoparticles in Different Soil Systems: An Important Study on the Development of Safe Nanoherbicides
(2022-12-01) Takeshita, Vanessa ; Munhoz-Garcia, Gustavo Vinicios ; Werk Pinácio, Camila ; Cardoso, Brian Cintra ; Nalin, Daniel ; Tornisielo, Valdemar Luiz ; Fraceto, Leonardo Fernandes ; Universidade de São Paulo (USP) ; Universidade Estadual Paulista (UNESP)
Nanoformulations have been used to improve the delivery of fertilizers, pesticides, and growth regulators, with a focus on more sustainable agriculture. Nanoherbicide research has focused on efficiency gains through targeted delivery and environmental risk reduction. However, research on the behavior and safety of the application of these formulations in cropping systems is still limited. Organic matter contained in cropping systems can change the dynamics of herbicide–soil interactions in the presence of nanoformulations. The aim of this study was to use classical protocols from regulatory studies to understand the retention and mobility dynamics of a metribuzin nanoformulation, compared to a conventional formulation. We used different soil systems and soil with added fresh organic material. The batch method was used for sorption–desorption studies and soil thin layer chromatography for mobility studies, both by radiometric techniques. Sorption parameters for both formulations showed that retention is a reversible process in all soil systems (H~1.0). In deep soil with added fresh organic material, nanoformulation was more sorbed (14.61 ± 1.41%) than commercial formulation (9.72 ± 1.81%) (p < 0.05). However, even with the presence of straw as a physical barrier, metribuzin in nano and conventional formulations was mobile in the soil, indicating that the straw can act as a barrier to reduce herbicide mobility but is not impeditive to herbicide availability in the soil. Our results suggest that environmental safety depends on organic material maintenance in the soil system. The availability can be essential for weed control, associated with nanoformulation efficiency, in relation to the conventional formulation.
Development and biological evaluation of nanoencapsulated-based pyrethroids with synergists for resistance management of two soybean pests: insights for new insecticide formulations
(2023-03-01) Boff, Jéssica S. ; Reis, Alexandre C. ; de Oliveira, Jhones L. ; Gross, Renata B. ; Fraceto, Leonardo F. ; Melo, Adriano A. ; Bernardi, Oderlei ; Universidade Federal de Sergipe (UFS) ; Universidade Estadual Paulista (UNESP)
Background: Chemical control is commonly used against Euschistus heros (F.) and Chrysodeixis includens (Walker) in soybean fields in South America. However, previous studies reported that these pests have reduced susceptibility to pyrethroids in Brazil. On this basis, we developed and evaluated nanoencapsulated-based bifenthrin (BFT) and λ-cyhalothrin (LAM) with the synergists piperonyl butoxide (PBO) and diethyl maleate (DEM) for insect resistance management (IRM). Results: Nanoformulations of BFT and LAM with PBO and DEM presented good physical–chemical characteristics and were stable. The spherical morphology of all systems and the encapsulation efficiency in nanostructured lipid carriers did not change when synergists were added. Nanoencapsulated BFT with DEM applied topically increased the susceptibility of E. heros to BFT by 3.50-fold. Similarly, nanoencapsulated BFT and LAM with PBO in diet-overlay bioassays increased the susceptibility of C. includens to both chemicals by up to 2.16-fold. Nanoencapsulated BFT and LAM with synergists also improve control efficacy of both species, causing higher mortality than commercial products containing these chemistries. Conclusions: It is possible to develop nanoencapsulated-based formulations of BFT and LAM with PBO or DEM, and these nanoformulations have the potential to improve control of E. heros and C. includens with recognized low susceptibility to pyrethroids. This study provides updates for designing new insecticide formulations for IRM. © 2022 Society of Chemical Industry.
Hybrid Integrator Topology with Digital Input Control and Analog Signal Processing
(2022-01-01) Fernandes, Felipe Olivera ; Martins, Everson ; De Andrade, Maria Gloria Cano ; Universidade Estadual Paulista (UNESP)
In this paper, an Analog-Digital integrator topology with selecting the input by gain control and analog processing, for use in general-purpose computers is intended. The integration function, control and of inputs variables condition were performed through development of analog-digital integrator circuits. The results showed that the topology is flexible in real-Time simulation and has good integration results in the tested conditions. The gain control architecture is a new way to control the input and the flexibility of the integrator.
A Non-cooperative Game-theoretic Distributed Control Approach for Power Quality Compensators
(2022-01-01) Burgos-Mellado, Claudio ; Bucarey, Victor ; Morales-Paredes, Helmo K. ; Muñoz-Carpintero, Diego ; Universidad de o'Higgins ; Universidade Estadual Paulista (UNESP)
This paper demonstrates that the Game Theory (GT) can be an effective tool for implementing a distributed control scheme for coordinating the compensation efforts of power quality compensators (PQCs) feeding a common unbalanced load. A non-cooperative game is formulated where each PQCs minimises its own interests, defined as the power losses that incur each PQC in carrying unbalanced power from its connection point in the system to the point of common coupling (PCC). By doing this, the whole system will move until it reaches a global equilibrium (the so-called Nash equilibrium). The power losses are calculated based on the conservative power theory (CPT), allowing the implementation of the proposal in the natural abc reference frame. A comparison (via simulations) between the proposed non-cooperative distributed scheme and a cooperative distributed approach based on the consensus theory shows that the proposed non-cooperative game compensates the PCC with fewer overall losses than the consensus-based cooperative approach, improving the efficiency of the whole compensation system.
Heterocyclic agrochemical hosted by cyclodextrin and hybrid cyclodextrin-silica materials: Characterization, release behavior, and mobility in soil
(2023-01-05) Bragança Carvalho, Lucas ; Abreu Venceslau, Adneia de Fátima ; Luz Ambrosio Breisch, Daniela ; Fernandes Fraceto, Leonardo ; Jaime, Carlos ; Matos Alves Pinto, Luciana ; Universidade Federal de Lavras (UFLA) ; Universidade Estadual Paulista (UNESP) ; Universidade Federal da Bahia (UFBA) ; Universitat Autònoma de Barcelona
Atrazine (ATZ) formulations are used to control a broad spectrum of weeds. The combination of ATZ with macromolecular systems, such as cyclodextrins (CDs), can improve its usefulness and herbicide efficacy related to the controlled release of the active ingredient. In this study, inclusion complexes of ATZ in CD and hybrid cyclodextrin-silica materials (CDSI) were prepared and characterized. Infrared spectral analysis of the inclusion compounds, concomitant with the suppression of the endothermic differential scanning calorimetry (DSC) peaks related to the fusion temperature of ATZ, confirmed the inclusion of ATZ in the functionalized and nonfunctionalized oligosaccharides. The linear increase in ATZ solubilization with the increasing addition of CD indicated that the inclusion stoichiometry was 1:1 in all studied systems. The increase in solubilization of the herbicide was approximately 1.3 times for α-CD and γ-CD, which had association constants of 20.3 and 13.4 L mol−1, respectively. The increase in solubility for α-CDSI and γ-CDSI was 3.3 and 2.7-fold, and the association constants were 161.1 and 111.1 L mol−1, respectively. Molecular mechanics (MM) calculations were performed using the force fields MM3* and AMBER*, and the results indicated that the most stable conformations resulted from the penetration of ATZ through the narrower cavity of the CDs. The MD calculations indicated three possible orientations for ATZ in the α-CD cavity, while for γ-CD the amplitude of the standard deviation of the energy values made it impossible to select a more favorable orientation. The ATZ release profile was affected by complexation. Over 22 h, more than 50% of noncomplexed ATZ was released, while for the complexes, less than 20% was released. The complexation, as well as the commercial formulation, provided variations in the development of Brassica juncea seedlings for the layers with higher concentrations of ATZ, thus agreeing with soil layer mobility studies indicated that complexation did not increase the leaching capacity of ATZ, which was mainly distributed in the upper soil layers, where it may be more available for herbicide control functions.

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