cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.6235502.v1
title: Use of the robust design methodology for identification of factors that contribute to the intensity of the “orange peel” aspect on painted bumper surfaces

description: Abstract Even with the considerable development of techniques for automotive paint in recent decades, the bumper is a car part that still has many problems related to the aspect of its painted surface. This study aimed to identify the clear coat application factors that affect on the intensity of orange peel appearance on painted bumpers surfaces and offer an optimum design of factors through the robust design methodology. In this research conducted in automated paint sector of a bumper company, the robust design helped in the identification of variability cause in a production process by applying an experiment and statistical techniques, in an agile and with little waste material way. The experiment tested various combinations of levels of the clear coat application factors (speed, flow, revolution per minute, operation voltage, atomizing air pressure) in the bumper samples. The intensity of the orange peel on coated surfaces samples was measured by a Wave Scan device that provides the wavelength reading as a function of two measures: Long Wave and Short Wave. The main results obtained by variance analysis of noise signal ratio showed that the factors that have significant effects on the value of the Short Wave response wavelength are: revolution per minute, operation voltage and the interactions flow*operation voltage and speed*operation voltage. The factors that significantly affected the response value of the Long Wave wavelength are: flow, atomizing air pressure, revolution per minute, operation voltage and the interaction speed*operation voltage. As a result of analysis of the noise signal mean, it is presented the factors optimum design: speed = 920 m / s; flow = 160 ml/min; atomizing air pressure = 180 bar; revolution per minute = 90 revolutions / minute; operation voltage = 180 kilovolts.
DOI: 10.6084/m9.figshare.6235499
title: Sharp Rejection and Wide Stopband Microstrip Lowpass Filters using Complementary Split Ring Resonators

description: Abstract Chebyshev microstrip lowpass filters with improved performance, achieved by means of circular complementary split ring resonators (CSRR), are presented. CSRR particles exhibit frequency rejection bandwidths in the vicinity of their resonant frequencies that can be used to meliorate both selectivity and stopband in microstrip lowpass filters. Two configurations have been used: a stepped-impedance model and a configuration using open-circuited stubs. Microstrip filters having 5, 7 and 9 poles were designed and fabricated. Selectivity values up to 86 dB/GHz and suppression levels reaching 60 dB in the stopband were obtained. The filters have cutoff frequency around 2 GHz and rejection band up to 10 GHz. The insertion of the designed CSRR resonators in the ground plane of the filters removes all the transmission spurious observed in the analyzed frequency band. No considerable variation in the passband group delay is observed in the CSRR-based lowpass filters. A comparison is made among the filters designed in this and other referenced works, considering their number of poles and size. The measured results are in good agreement with the simulated ones. The presented filters can be candidates for applications using the VHF, UHF and L bands, being also very effective in the rejection of the S and C bands. Applications that demand the rejection of the first half of the X band can also use the filters detailed in this paper.
DOI: 10.6084/m9.figshare.6235499.v1
title: Sharp Rejection and Wide Stopband Microstrip Lowpass Filters using Complementary Split Ring Resonators

description: Abstract Chebyshev microstrip lowpass filters with improved performance, achieved by means of circular complementary split ring resonators (CSRR), are presented. CSRR particles exhibit frequency rejection bandwidths in the vicinity of their resonant frequencies that can be used to meliorate both selectivity and stopband in microstrip lowpass filters. Two configurations have been used: a stepped-impedance model and a configuration using open-circuited stubs. Microstrip filters having 5, 7 and 9 poles were designed and fabricated. Selectivity values up to 86 dB/GHz and suppression levels reaching 60 dB in the stopband were obtained. The filters have cutoff frequency around 2 GHz and rejection band up to 10 GHz. The insertion of the designed CSRR resonators in the ground plane of the filters removes all the transmission spurious observed in the analyzed frequency band. No considerable variation in the passband group delay is observed in the CSRR-based lowpass filters. A comparison is made among the filters designed in this and other referenced works, considering their number of poles and size. The measured results are in good agreement with the simulated ones. The presented filters can be candidates for applications using the VHF, UHF and L bands, being also very effective in the rejection of the S and C bands. Applications that demand the rejection of the first half of the X band can also use the filters detailed in this paper.
DOI: 10.6084/m9.figshare.6235496
title: Enhancing and validating a low-cost photogate

description: Abstract This paper presents the development and validation of a low cost instrument that can be used for time interval measurements, and in other physics experiments. It is proposed to build a photogate combining the simplicity and economy, making it simpler and cheaper than those on the market. The construction of this instrument is based on the use of a light-dependent resistor (LDR) and a LASER pointer, with simple and elementary connections, which characterizes it as a low-cost measuring instrument. Its validation was carried out by comparing the results of the moment of inertia of a homogeneous and thin bar and the experiments carried out in a laboratory, proving its effectiveness as a time variation collection instrument. It is also proposed an experimental activity, whose objective is to determine the landing point of a sphere thrown horizontally from the top of a table at any speed. Its use tends to facilitate the diffusion and access to this type of instrument of measures between high school teachers and educational institutions, being ideal to constitute a science laboratory.
DOI: 10.6084/m9.figshare.6235496.v1
title: Enhancing and validating a low-cost photogate

description: Abstract This paper presents the development and validation of a low cost instrument that can be used for time interval measurements, and in other physics experiments. It is proposed to build a photogate combining the simplicity and economy, making it simpler and cheaper than those on the market. The construction of this instrument is based on the use of a light-dependent resistor (LDR) and a LASER pointer, with simple and elementary connections, which characterizes it as a low-cost measuring instrument. Its validation was carried out by comparing the results of the moment of inertia of a homogeneous and thin bar and the experiments carried out in a laboratory, proving its effectiveness as a time variation collection instrument. It is also proposed an experimental activity, whose objective is to determine the landing point of a sphere thrown horizontally from the top of a table at any speed. Its use tends to facilitate the diffusion and access to this type of instrument of measures between high school teachers and educational institutions, being ideal to constitute a science laboratory.
DOI: 10.6084/m9.figshare.6235493
title: Water quality modeling at Poti river in Teresina (Piauí, Brazil)

description: ABSTRACT The uncontrolled growth of Piauí’s capital, in Brazil, characterized mainly by the occupation of the banks of the river Poti and the existence of illegal connections of raw sewage in rainwater drainage pipes, has contributed significantly to water pollution in the basin of Parnaíba river (semiarid region of Brazil). This research aims at performing the mathematical modeling of water quality in an area of 36.8 km of the Poti river, based on the QUAL-UFMG platform. The research is presented as the first study involving modeling of water quality in said river. Modeled components were: dissolved oxygen (DO), biochemical oxygen demand (BOD) and thermotolerant coliforms (TC). The results obtained from field measurements indicated nonconformities of the parameter TC with respect to CONAMA Resolution nº 357/2005. The calibration of the decay coefficients for each parameter resulted in mean deviations between measured and modeled data of up to 20% and Nash-Sutcliffe efficiency coefficients higher than 0.75, which indicate that the QUAL-UFMG can be used as a basis for predicting the water quality in rivers of semiarid areas. The calibrated model was also compared to field data obtained from the literature. Finally, model simulations were performed for different flow scenarios (minimum and maximum), with consistent results that can be used for the management of the Piauí state water resources.
DOI: 10.6084/m9.figshare.6235493.v1
title: Water quality modeling at Poti river in Teresina (Piauí, Brazil)

description: ABSTRACT The uncontrolled growth of Piauí’s capital, in Brazil, characterized mainly by the occupation of the banks of the river Poti and the existence of illegal connections of raw sewage in rainwater drainage pipes, has contributed significantly to water pollution in the basin of Parnaíba river (semiarid region of Brazil). This research aims at performing the mathematical modeling of water quality in an area of 36.8 km of the Poti river, based on the QUAL-UFMG platform. The research is presented as the first study involving modeling of water quality in said river. Modeled components were: dissolved oxygen (DO), biochemical oxygen demand (BOD) and thermotolerant coliforms (TC). The results obtained from field measurements indicated nonconformities of the parameter TC with respect to CONAMA Resolution nº 357/2005. The calibration of the decay coefficients for each parameter resulted in mean deviations between measured and modeled data of up to 20% and Nash-Sutcliffe efficiency coefficients higher than 0.75, which indicate that the QUAL-UFMG can be used as a basis for predicting the water quality in rivers of semiarid areas. The calibrated model was also compared to field data obtained from the literature. Finally, model simulations were performed for different flow scenarios (minimum and maximum), with consistent results that can be used for the management of the Piauí state water resources.
DOI: 10.6084/m9.figshare.6235490
title: Elaboration and characterization of pectin-gellan films added with concentrated supernatant of Streptococcus infantarius fermentations, and EDTA: effects on the growth of Escherichia coli, Staphylococcus aureus and Listeria monocytogenes in a Mexican cheese medium, and physical-mechanical properties

description: Abstract Films were prepared with 0.2% (w/v) gellan gum, 1% (w/v) citric pectin, 0.5% (w/v) glycerol, 5 mM CaCl2, 0.05 M Ethylenediaminetetraacetic acid (EDTA), and different concentrations of an antimicrobial activity-concentrated supernatant (AMC) obtained from fermentations of Streptococcus infantarius, which produces bacteriocin-like inhibitory substances (i.e., treatments F1, F2 and F3 with 75, 90 and 120 arbitrary units (AU)/mL, respectively). The treatments were based on a minimum-inhibitory-concentration (i.e., AMC, 90 AU/mL, plus EDTA, 0.05 M) for Escherichia coli, Staphylococcus aureus and Listeria monocytogenes growing in brain-heart-infusion medium at 35 °C. The films hindered the bacterium growth in selective media: E. coli -MacConkey, S. aureus-Baird Parker and L. monocytogenes -Oxford, during 30 days at 25 °C. Moreover, the F2 films entirely inhibited the growth of the tested bacteria in a Mexican cheese medium, in 7-day cultures at 35 °C; contrariwise, controls with no film exhibited bacterial growths in the range 107 -109 CFU/g. The physical-mechanical properties of the films were changed by the addition of EDTA-AMC, being (F2 film)/(control-film with no AMC nor EDTA): Young’s modulus (MPa), 1,394/707; Elongation at break (%), 1.9/9.3; Stress at break (MPa), 5.7/12.6; Water Vapour Permeability (10-11 g m Pa-1 s-1 m -2), 3/20, and Oxygen Permeability (10-12 g m Pa-1 s -1 m-2), 1.9/1.2.
DOI: 10.6084/m9.figshare.6235490.v1
title: Elaboration and characterization of pectin-gellan films added with concentrated supernatant of Streptococcus infantarius fermentations, and EDTA: effects on the growth of Escherichia coli, Staphylococcus aureus and Listeria monocytogenes in a Mexican cheese medium, and physical-mechanical properties

description: Abstract Films were prepared with 0.2% (w/v) gellan gum, 1% (w/v) citric pectin, 0.5% (w/v) glycerol, 5 mM CaCl2, 0.05 M Ethylenediaminetetraacetic acid (EDTA), and different concentrations of an antimicrobial activity-concentrated supernatant (AMC) obtained from fermentations of Streptococcus infantarius, which produces bacteriocin-like inhibitory substances (i.e., treatments F1, F2 and F3 with 75, 90 and 120 arbitrary units (AU)/mL, respectively). The treatments were based on a minimum-inhibitory-concentration (i.e., AMC, 90 AU/mL, plus EDTA, 0.05 M) for Escherichia coli, Staphylococcus aureus and Listeria monocytogenes growing in brain-heart-infusion medium at 35 °C. The films hindered the bacterium growth in selective media: E. coli -MacConkey, S. aureus-Baird Parker and L. monocytogenes -Oxford, during 30 days at 25 °C. Moreover, the F2 films entirely inhibited the growth of the tested bacteria in a Mexican cheese medium, in 7-day cultures at 35 °C; contrariwise, controls with no film exhibited bacterial growths in the range 107 -109 CFU/g. The physical-mechanical properties of the films were changed by the addition of EDTA-AMC, being (F2 film)/(control-film with no AMC nor EDTA): Young’s modulus (MPa), 1,394/707; Elongation at break (%), 1.9/9.3; Stress at break (MPa), 5.7/12.6; Water Vapour Permeability (10-11 g m Pa-1 s-1 m -2), 3/20, and Oxygen Permeability (10-12 g m Pa-1 s -1 m-2), 1.9/1.2.
DOI: 10.6084/m9.figshare.6235487
title: Jambolan sherbets overrun, color, and acceptance in relation to the sugar, milk, and pulp contents in formulation

description: Abstract The aim of this study was to evaluate in sherbet formation the effects of sugar, milk, and jambolan pulp quantity on the overrun, color, physicochemical characteristics, microbiological characteristics, and acceptance of the experimental sherbets, in addition to evaluating the bioactive compounds of the selected product. Seven formulations were established through the Simplex method. The formulation with 20g 100g-1 sugar, 45g 100g-1 milk, and 35g 100g-1 jambolan pulp was selected (S5) because it was included among the most accepted sensorially (S4 and S5), and also presented higher overrun, chroma, SST/AT, and pH than S4, receiving the scores 8.0; 8.2, 6.4 and 7.1 and 6.1, respectively, for appearance, color, flavor, texture, and odor. The selected sherbet presented a high total phenolic compound content of 192mg gallic acid g-1, and a percentage of DPPH inhibition of 73%. It is concluded that it is possible to produce jambolan sherbet with desirable physical, chemical, microbiological, and sensory characteristics, which can increase the possibilities of applying the fruit as an ingredient in the edible ice cream industry.
DOI: 10.6084/m9.figshare.6235487.v1
title: Jambolan sherbets overrun, color, and acceptance in relation to the sugar, milk, and pulp contents in formulation

description: Abstract The aim of this study was to evaluate in sherbet formation the effects of sugar, milk, and jambolan pulp quantity on the overrun, color, physicochemical characteristics, microbiological characteristics, and acceptance of the experimental sherbets, in addition to evaluating the bioactive compounds of the selected product. Seven formulations were established through the Simplex method. The formulation with 20g 100g-1 sugar, 45g 100g-1 milk, and 35g 100g-1 jambolan pulp was selected (S5) because it was included among the most accepted sensorially (S4 and S5), and also presented higher overrun, chroma, SST/AT, and pH than S4, receiving the scores 8.0; 8.2, 6.4 and 7.1 and 6.1, respectively, for appearance, color, flavor, texture, and odor. The selected sherbet presented a high total phenolic compound content of 192mg gallic acid g-1, and a percentage of DPPH inhibition of 73%. It is concluded that it is possible to produce jambolan sherbet with desirable physical, chemical, microbiological, and sensory characteristics, which can increase the possibilities of applying the fruit as an ingredient in the edible ice cream industry.
DOI: 10.6084/m9.figshare.6235484
title: The effect of micronized corn fiber on body weight, glycemia, and lipid metabolism in rats fed cafeteria diet

description: Abstract During corn industrial dry milling, a residue rich in dietary fibers is generated. This study aimed to evaluate the effects of micronized corn fiber (MCF) as part of a cafeteria diet in the macronutrient metabolism and body weight. Wistar male rats, with initial body weight of 249 ± 14 g (n = 13), received AIN-93M diet (Group 1) or cafeteria diet (Groups 2, 3 and 4), composed of commercial ration, cookies, fried potato sticks, milk chocolate, bacon and chicken liver pâté. Groups 3 and 4 received MCF to replace 100 and 50% of the cellulose from the AIN-93M diet, respectively. After 35 days, blood, tissues and feces were collected. Data were analyzed by ANOVA followed by Tukey test (p &lt; 0.10). The weight gain of the animals increased by 25.9%, 20.8% and 22.0%, when fed cafeteria diet or 100 and 50% of MCF respectively, compared to the control group, although food consumption did not differ between them. Body weight and food efficiency ratio did not differ between the groups fed cafeteria diet with or without MCF. The addition of MCF to the cafeteria diet did not alter the animal lipid profile and glycemia, however, the accumulation of lipids in their livers was similar to the control group. The intake of 100% MCF resulted in higher fecal weight and fecal excretion of lipids, and lower fecal nitrogen, lipid absorption and lipid deposition in the liver than the cafeteria diet. In conclusion, MCF has a potential to improve intestinal transit and lipid excretion, but showed no benefit on blood lipid and glucose levels.
DOI: 10.6084/m9.figshare.6235484.v1
title: The effect of micronized corn fiber on body weight, glycemia, and lipid metabolism in rats fed cafeteria diet

description: Abstract During corn industrial dry milling, a residue rich in dietary fibers is generated. This study aimed to evaluate the effects of micronized corn fiber (MCF) as part of a cafeteria diet in the macronutrient metabolism and body weight. Wistar male rats, with initial body weight of 249 ± 14 g (n = 13), received AIN-93M diet (Group 1) or cafeteria diet (Groups 2, 3 and 4), composed of commercial ration, cookies, fried potato sticks, milk chocolate, bacon and chicken liver pâté. Groups 3 and 4 received MCF to replace 100 and 50% of the cellulose from the AIN-93M diet, respectively. After 35 days, blood, tissues and feces were collected. Data were analyzed by ANOVA followed by Tukey test (p &lt; 0.10). The weight gain of the animals increased by 25.9%, 20.8% and 22.0%, when fed cafeteria diet or 100 and 50% of MCF respectively, compared to the control group, although food consumption did not differ between them. Body weight and food efficiency ratio did not differ between the groups fed cafeteria diet with or without MCF. The addition of MCF to the cafeteria diet did not alter the animal lipid profile and glycemia, however, the accumulation of lipids in their livers was similar to the control group. The intake of 100% MCF resulted in higher fecal weight and fecal excretion of lipids, and lower fecal nitrogen, lipid absorption and lipid deposition in the liver than the cafeteria diet. In conclusion, MCF has a potential to improve intestinal transit and lipid excretion, but showed no benefit on blood lipid and glucose levels.
DOI: 10.6084/m9.figshare.6235478
title: CO Tolerance and Stability of Proton Exchange Membrane Fuel Cells with Nafion® and Aquivion® Membranes and Mo-Based Anode Electrocatalysts

description: This work presents a CO tolerance study of PtMo/C (70:30, Pt:Mo) and Pt/MoO2-C anode catalysts on proton exchange membrane fuel cells (PEMFC) with Nafion® and Aquivion® ionomer membranes. Results denote improved activity for the hydrogen oxidation reaction (HOR) in the presence of CO on both anode catalysts at 85 ºC. Experiments of identical location transmission electron microscopy evidenced very good stability of the Pt particles along an accelerate stress test (AST) applied to the Mo-based anode catalysts. However, a crossover of degradation Mo products originated in the anode and going to the cathode takes place along this anode AST, causing a PEMFC performance decay. A very little effect of the nature of the membrane, Nafion® or Aquivion®, is observed over these crossover phenomena. Results also denote that when operating at appropriate high temperatures (105 ºC for Nafion® and 125 ºC for Aquivion®), there is no need of incorporating unstable oxophilic transition metals on Pt to achieve improved CO tolerance on PEMFCs, when the CO level in the hydrogen fed is of the order of 100 ppm.
DOI: 10.6084/m9.figshare.6235475
title: Total Synthesis of Altissimacoumarin D, a Small Molecule Sirtuin1 Activator

description: The total synthesis of the plant natural product altissimacoumarin D was achieved by the Mitsunobu alkylation of isofraxidin by geraniol. Isofraxidin was prepared from 2,4-dihydroxybenzaldehyde in five steps. The key reaction was the Knoevenagel condensation of an ortho-hydroxybenzaldehyde with Meldrum's acid under neutral conditions in water and one-pot acid catalyzed cyclization to the coumarin.
DOI: 10.6084/m9.figshare.6235478.v1
title: CO Tolerance and Stability of Proton Exchange Membrane Fuel Cells with Nafion® and Aquivion® Membranes and Mo-Based Anode Electrocatalysts

description: This work presents a CO tolerance study of PtMo/C (70:30, Pt:Mo) and Pt/MoO2-C anode catalysts on proton exchange membrane fuel cells (PEMFC) with Nafion® and Aquivion® ionomer membranes. Results denote improved activity for the hydrogen oxidation reaction (HOR) in the presence of CO on both anode catalysts at 85 ºC. Experiments of identical location transmission electron microscopy evidenced very good stability of the Pt particles along an accelerate stress test (AST) applied to the Mo-based anode catalysts. However, a crossover of degradation Mo products originated in the anode and going to the cathode takes place along this anode AST, causing a PEMFC performance decay. A very little effect of the nature of the membrane, Nafion® or Aquivion®, is observed over these crossover phenomena. Results also denote that when operating at appropriate high temperatures (105 ºC for Nafion® and 125 ºC for Aquivion®), there is no need of incorporating unstable oxophilic transition metals on Pt to achieve improved CO tolerance on PEMFCs, when the CO level in the hydrogen fed is of the order of 100 ppm.
DOI: 10.6084/m9.figshare.6235475.v1
title: Total Synthesis of Altissimacoumarin D, a Small Molecule Sirtuin1 Activator

description: The total synthesis of the plant natural product altissimacoumarin D was achieved by the Mitsunobu alkylation of isofraxidin by geraniol. Isofraxidin was prepared from 2,4-dihydroxybenzaldehyde in five steps. The key reaction was the Knoevenagel condensation of an ortho-hydroxybenzaldehyde with Meldrum's acid under neutral conditions in water and one-pot acid catalyzed cyclization to the coumarin.