In many applications, such as fuel storage tanks and fuel lines, galvanized steel is used as a construction material which comes into contact with biodiesel. Considering that biodiesel is more corrosive than petroleum diesel, studies that aim to increase the corrosion resistance of galvanized steel in this environment are required. The present work investigates how the chemical conversion treatment in the oxalic acid solution affects the corrosion resistance of galvanized steel in soybean biodiesel (B100) in the absence and presence of the natural additives the extract the turmeric, clove, ginger, stone breaker, and rosemary. The results obtained indicate that the conversion treatment reduces the corrosion rate of the zinc coating in soybean biodiesel in the absence and presence of additives, and in this condition the effect of the conversion treatment depends on the additive used. applications lines diesel required B100 B (B100 turmeric clove ginger breaker rosemary B10 (B10 B1 (B1 (B

Abstract This work investigates the effect of the addition of glycerol on the microstructure, corrosion resistance, and efficiency of the electrodeposition process of Cu coating in an acid sulphate solution. The morphology and microstructures of electrodeposits were analyzed using Scanning Electron Microscopy (SEM), Spectrometry X-Ray Diffraction (XRD) and laser scanning confocal microscopy (LSCM). Evaluation of the corrosion resistance was performed in 2.0 mol⋅L−1 NaCl by means of weight loss tests and electrochemical techniques. The addition of glycerol resulted in a decrease in grain and crystallite sizes, a decrease in roughness and an increase in the tensile strain of the coating. The deposition efficiency and the corrosion resistance increased with the addition of glycerol exhibiting a maximum value at the concentration of 0.42 mol⋅L−1, increasing the efficiency of electrodeposition by approximately 96%. This is related to the roughness of the coating, which is minimal at this concentration.

RESUMO: O cultivo do cacau tem grande importância socioeconômica mundial. Os amêndoas de cacau são a matéria-prima essencial para a produção de chocolate. A variabilidade do cacaueiro avaliada representa apenas uma pequena fração da diversidade genética existente, principalmente na região amazônica. Além disso, apenas uma pequena parte dessa variabilidade foi explorada no melhoramento de cacau. Dessa forma, o presente estudo teve como objetivo realizar a avaliação genética e seleção de clones de cacau, com base em características morfo-agronômicas. Para isso, foram avaliados 145 clones, durante 37 colheitas, em quatro anos consecutivos. As seguintes características de frutos e sementes foram avaliadas: número total de frutos colhidos (NTFC), número total de frutos sadios (NTFS), peso de sementes úmidas dos frutos sadios (PSUFS), peso médio de sementes úmidas dos frutos sadios (PMSUFS), peso de sementes secas dos frutos sadios (PSSFS), peso médio de sementes secas dos frutos sadios (PMSSFS), porcentagem de frutos com vassoura-de-bruxa (PFVB), porcentagem de frutos com broca (PFBR), porcentagem de frutos com sementes germinadas (PFSG), número de ramos com vassoura-de-bruxa (NRVB) e número de almofadas florais com vassoura-de-bruxa (NAFVB). Diferenças significativas (P < 0,05) entre os clones foram observadas para todas as características, o que revela uma expressiva variabilidade e possibilidade de ganhos com a seleção. As maiores correlações significativas (P < 0,05) ocorreram entre os caracteres NTFC e NTFS (0,94), NTFS e PMSUFS (0,86) e, NTFS e PMSSFS (0,86). Com base no índice de seleção, os clones POUND 12 e CAB 12, 228, 253, 257, 258 e 422 foram considerados os mais adequados para a seleção.

ABSTRACT: The cultivation of cocoa is of great socio-economic importance worldwide. Cocoa beans are the essential raw material for chocolate production. The variability of cacao studied presents only a small fraction of the existing genetic diversity, mainly in the Amazon region. Furthermore, just a small part of this variability has been exploited in cocoa breeding. Thus, the present study processed the genetic evaluation and selection of cocoa clones, based on morpho-agronomical traits. For this, we evaluated 145 clones, during 37 harvests from, four consecutive years. The following traits were evaluated: total number of fruits collected (TNFC), total number of healthy fruits (TNHF), weight of wet seeds from healthy fruits (WWSHF), average weight of wet seeds per healthy fruit (AWWSHF), weight of dry seeds from healthy fruit (WDSHF), average weight of dry seeds per healthy fruit (AWDSHF), percentage of fruits with witches’ broom disease (PFWB), percentage of fruits with borer (PFBR), percentage of fruits with germinated seeds (PFGS), number of branches with witches’ broom disease (NBWB), and number of inflorescence with witches’ broom disease (NIWB). Significant differences (P < 0.05) among the clones were observed for all traits, which reveal an expressive variability and possibility of gains with selection. The highest significant correlations (P < 0.05) occurred between traits TNFC and TNHF (0.94), TNHF and AWWSHF (0.86), and TNHF and AWDSHF (0.86). Based on the selection index, the clones POUND 12 and CAB 12, 228, 253, 257, 258, and 422 were the most suitable for selection.

This paper evaluates the effect of adding glycerol to the electrodeposition bath on the deposition efficiency and characteristics of Ni-Mo coating in concentrations ranging from 0.07 to 0.82 mol.L-1. Evaluation of the corrosion resistance was performed by means of weight loss tests in four different periods of immersion. Electrochemical techniques, such as obtaining polarization curves, linear polarization resistance, corrosion current density, corrosion potential, and electrochemical impedance spectroscopy were applied. Corrosion measurements were obtained in 0.5 mol.L-1 NaCl acid solution and 0.5 mol.L-1 NaOH alkaline solution. The morphology and microstructures of electrodeposited were analyzed using Scanning Electron Microscopy and Spectrometry X-Ray Diffraction. The effect of glycerol on Ni-Mo hardness was evaluated by Vickers microhardness measurements. The presence of glycerol in the electrodeposition bath increased the grain size and decreased the hardness of the coating. However, it promoted the formation of a more compact and less porous coating, increasing the corrosion resistance of the coating. Moreover, the addition of 0.82 mol.L-1 glycerol increases current efficiency, thereby reducing the amount of energy consumed during electroplating.

Abstract The use of natural additives in biodiesel has been investigated, however, there is limited information in the literature in relation to their influence on corrosion resistance and oxidative stability. This work aims to investigate the oxidative stability of biodiesel and the corrosion resistance of carbon steel (AISI 1020) in contact with soybean biodiesel solutions (B100) in the presence and absence of natural additives such as: rosmarinic acid, curcumin, gingerol, eugenol, thymol and quercetin. Corrosion and microscopy tests were used to assess corrosion resistance. The Rancimat technique was used to study oxidative stability. The results obtained indicate that curcumin was the best additive in relation to oxidative stability, while rosmarinic acid showed better performance in inhibiting corrosion. The effect of these substances is related to the presence of phenolic compounds or the existence of oxygen in its molecular structure.

ABSTRACT As primary decomposers of organic matter, mucoralean fungi have an important ecological role in edaphic systems in the Atlantic Forest. However, there is a knowledge gap regarding how communities of Mucorales are structured in soils of Atlantic Forest areas, and whether these communities are influenced by edaphic attributes in this domain. Thus, the current study aimed to understand the influence of edaphic attributes linked to species richness, abundance and composition of Mucorales in dense ombrophilous forest, ‘tabuleiro’ forest, sandbank and mangrove ecosystems located in Pernambuco, Brazil. Altogether, twenty-three taxa, including seven new records, were reported from soil samples from the ecosystems. Species composition was similar among the ecosystems, except for mangrove, while species richness and diversity of Mucorales were highest in dense ombrophilous forest and ‘tabuleiro’. Together the soil variables were responsible for 35.5 % of the variation in species composition, with pH being responsible for 53.32 % and 47.24 % of the variation in richness and abundance of these communities, respectively. These data indicate that pH is the most important attribute in delimiting the structure of mucoralean communities in the study areas, with influence on the composition, richness, and abundance of these fungi.

Abstract The Zn coatings obtained through electrodeposition are used to protect steel substrates from corrosion. In general, organic additives are added to the deposition bath in order to improve deposition characteristics such as corrosion resistance, hardness and deposition efficiency. Despite of the literature present information about the various organic additives effects on Zn coating properties there is no analysis of organic compounds with free electron-containing radicals, such as formic acid and cyclohexylamine. The formic acid has oxygen atoms with free electrons, whereas cyclohexylamine contains nitrogen with free electrons. Aiming at overcoming this gap, this manuscript presents an analysis of the effect in addition of formic acid mixture and cyclohexylamine on the deposition flow efficiency, corrosion resistance, hardness, roughness and micro-structure of Zn coating on carbon steel AISI 1020. The corrosion resistance evaluation was performed by potentiodynamic polarization determined by polarization resistance and weight loss tests as well. The analisys of morphology and electrodeposited microstructures were made by the Scanning Electron Microscopy (SEM) and Spectrometry X-Ray Diffraction (XRD). The Zn coatings were obtained from chloride deposition baths at constant pH 5. Results showed that corrosion resistance in the 0.5 mol/L NaCl solution of Zn coatings increases with the addition of the mixture of the formic acid and / or cyclohexylamine. Also, the corrosion resistance is higher with mixture than with additives alone. The addition of the mixture formic acid and cyclohexylamine increases the basal plane presence (0 0 2). However, the basal plane presence (0 0 2) does not increase when formic acid and cyclohexylamine are added alone which indicates a synergic effect of formic acid and cyclohexylamine in in the plan promotion (0 0 2). Also, was observed that an addition of formic acid mixture and cyclohexylamine increases the current deposition efficiency, decreases the roughness and raises the Zn coating hardness.

Reinforced concrete is the main structural material used in the world in the construction of bridges, roads and commercial and residential buildings. One effective method for preventing corrosion of steel reinforcement is the application of galvanic coatings to the reinforcement itself. The present study evaluated the performance of three groups of reinforcing steel bars (black steel, used as a reference and rebars electroplated with Zinc and Zinc-Nickel alloys) to corrosion and adherence to the concrete matrix. For the analysis of corrosion, the specimens were subjected to two different accelerated corrosion tests: salt spray exposure and wet and dry semi-cycles. The corrosion potential was measured for the qualitative monitoring of the corrosion process and the corrosion rate was estimated. In order to evaluate the steel-concrete adherence, the pullout test was used, in accordance with RILEM-CEB-FIP. The results showed that Zinc and Zinc-Nickel coatings increased the durability of the reinforcing bars and the accelerated corrosion test of wetting and drying cycles proved to be more aggressive compared to the salt spray method to evaluate the corrosion process in the reinforced concrete specimens. Additionally, galvanized reinforcement reduced adherence to the concrete matrix.

Zinc electrodeposition is an economical process of Zn coating compared to conventional galvanic process. The galvanizing process is used in various industrial sectors to protect ferrous alloys during the corrosion process. In buildings, the galvanizing process is widely used to coat mortar protective screens. The electrodeposition of zinc has a relatively low cost compared to other coating materials for the same purpose; however, its corrosion resistance is lower than that of most protective deposits. This study evaluated the effect of adding glycerol to the electrodeposition bath on the corrosion resistance, deposition efficiency, morphology and microstructure of the zinc electrodeposit in concentrations ranging from 0.03 to 0.82 M. The electrodeposition was performed on carbon steel AISI 1020 with a current density of 10 mA.cm-2. The electroplating solution composition was 0.10 M ZnCl2, 2.80 M KCl and 0.32 M H3BO3. Electrodeposition time was 17.56 min, 5 µm thick coating, equivalent to the mass of 7.166E-3 g of zinc on the steel surface. Evaluation of the corrosion resistance was performed by means of the electrochemical tests of Anodic Voltammetry, Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy (EIS) as well as Weight Loss tests in NaCl 0.5 M in 4 (four) different period of immersion. The morphology and microstructures of electrodeposited were analyzed using the techniques of Scanning Electron Microscopy (SEM) and Spectrometry X-Ray Diffraction (XRD). The presence of glycerol in the electrodeposition bath decreased the deposition efficiency; however, it increased corrosion resistance and promoted the formation of more compact and refined electrodeposited coatings. Moreover, the results showed that the corrosion rate does not vary linearly with the addition of glycerol.

ABSTRACT Here, Quambalaria fabacearum and Neopestalotiopsis brasiliensis are introduced as new species from Brazil, isolated as endophyte from Mimosa tenuiflora and causing post-harvest rot disease on fruits of Psidium guajava, respectively. Diaporthe inconspicua is emended to include a more detailed morphological description. Neopestalotiopsis egyptiaca is reported as new to the Americas and as causing post-harvest rot disease on fruits of Psidium guajava, while Umbelopsis isabellina is reported as endophyte.

Objetivou-se avaliar a eficácia da aplicação foliar de silício nos aspectos fisiológicos e bioquímicos em um genótipo de Theobroma cacao inoculado com Moniliophthora perniciosa, fungo causador da vassoura-de-bruxa, importante doença da cacauicultura. Mudas do genótipo Catongo foram submetidas a um experimento com dois fatores (inoculação e não inoculação das plantas com M. perniciosa) cada um com dois níveis de Si (0.0 mg e 1.0 mg mL-1 de AgriSil contendo 98% de SiO2 aplicado por pulverização). Verificou-se que plantas inoculadas e submetidas à aplicação foliar com Si apresentaram aumento na fotossíntese, das atividades de peroxidases, quitinases e polifenoloxidases e da densidade estomática. Os resultados indicam que a aplicação de silício é benéfica aumentando as defesas contra Moniliphthora perniciosa em mudas de cacaueiros.

This study aimed to verify the efficiency of silicon leaf application in the physiological and biochemical characteristics in a Theobroma cacao genotype inoculated with Moniliophthora perniciosa fungus, which causes the witches’ broom disease, important cocoa disease in Brazil and worldwide. Seedlings of Catongo genotype were used. The experimental design used was a randomized block design with four replicates, including two inoculation factors (inoculated and non-inoculated plants), each one with two levels of silicon application (0.0 mg and 1.0 mg mL-1 with AgriSil containing 98% of SiO2). We observed that plants that were inoculated with M. perniciosa and subjected to leaf application with silicon presented enhanced photosynthesis, peroxidases, chitinase, polyphenoloxidases activities and stomatal density. Results have shown that silicon application is beneficial and increases the defenses against Moniliophthora perniciosa in cocoa seedlings.

In this work, the allantoin was encapsulated with galactomannan extruded from Delonyx regia, by the spray drying technique. The microparticles obtained were structurally characterized by infrared spectroscopy (IR), thermal analysis, scanning electron microscopy (SEM) and the controlled release profile was evaluated. The results of IR suggested the formation of the polymeric wall of the microcapsules and SEM revealed spherical particles with an average size range of 2.84 ± 0.41 µm. X-ray diffraction showed the loss of crystallinity of the active after encapsulation and differential explanatory calorimetry exhibited the loss of its peak melt. The encapsulation efficiency for the microparticles was approximately 84% for the different environmental conditions. The coating of allantoin with the biopolymer promoted a gradual release of the drug over a period of 6 hours and these results are in accordance with the Brazilian Pharmacopoeia. The set of results obtained in this work is relevant and accredits the system developed as a possible alternative for the formation of encapsulated natural drugs destined to possible treatments of cutaneous cellular regeneration.

Abstract Mucorales comprises fungi commonly isolated as saprobes from soil, dung, stored grains and plants. Although these fungi have been studied in several countries, there are relatively a few reports of them in semi-arid areas. Therefore, the aims of the present study were to assess and compare the Mucorales communities in dung from different species and breeds of herbivores in the semi-arid of Pernambuco, based on the frequency of occurrence and species richness of these fungi. Samples of dung collected in the cities of Arcoverde, Serra Talhada and Sertânia were incubated in moist chambers in triplicate. Altogether, 24 taxa of Mucorales distributed in the genera Absidia, Circinella, Cunninghamella, Lichtheimia, Mucor, Pilobolus, Rhizopus and Syncephalastrum were identified. The highest species richness was found in sheep excrement. Mucor circinelloides f. griseo-cyanus was the most common taxon, followed by M. ramosissimus. The similarity of the composition of Mucorales species was greatest between the excrements of Guzerá and Sindi breeds (bovine). All mucoralean species isolated are being cited for the first time from animal dung found in Caatinga and a new species of Mucor was recorded. An identification key for species of Mucorales from dung in the semi-arid region of Brazil is provided.

RESUMO Este trabalho foi concebido com os objetivos de determinar matematicamente os pontos de mudança da forma do fuste (pmf), o número de mudanças na forma geométrica, ajustar e comparar modelos matemáticos para estimar os diâmetros ao longo do fuste de Pinus taeda L. Os dados foram amostrados em árvores que cresceram em povoamento implantado em espaçamento de 2,50 x 2,50 m e manejado com dois desbastes, aos 9 e 14 anos, e corte final aos 30 anos pertencentes à Klabin S.A., em Telêmaco Borba, estado do Paraná. Quarenta árvores das classes médias e dominantes foram abatidas e cubadas pelo Método de Smalian, nas posições fixas de 0,10 m; 0,30 m; 0,80 m; 1,30 m; e após em comprimentos de 1 em 1 m, até a altura total. Na parte relativa à copa, os pontos de medição foram deslocados para os entrenós e a seguir foram retiradas fatias para análise de tronco, resultando, quando considerada a idade, em conjunto de dados relativos a 649 árvores com idades entre 8 a 30 anos, das quais foram selecionadas aleatoriamente, 50 árvores em cada classe de pmf para modelagem. As árvores foram agrupadas segundo os pmf de acordo com as quantidades de pontos definidos pela segunda derivada do polinômio do 5° ajustado para cada árvore. Com base nas estatísticas de ajuste e precisão na análise gráfica dos resíduos, nas estatísticas viés (v), média das diferenças (md) e desvio padrão das diferenças (dpd) foi selecionado o Polinômio de quinto grau para estimar os diâmetros em alturas relativas do tronco e, alternativamente, o modelo de Garay, seguido do modelo de Max e Burkhart com dois ou modificado para um segmento conforme o número de pmf definidos na derivada.

ABSTRACT This work was planned to describe the change point of stem taper (pmf), the number of geometric change points, adjust and compare mathematical models to predict diameters along of stem of Pinus taeda L. The data sampled were measured on trees growing in stands implanted with spacement of 2,50 x 2,50m, thinned at 9 and 14 years and final cut at 30 years old, from Klabin S.A., Telêmaco Borba, Paraná state, Brazil. Fourty trees between the average and dominant trees were cut and measured with Smalian method at the positions 0,10m; 0,30m; 0,80m; 1,30m; and from them at each 1m to the top. At crown part the measured point were moved among knot. After that, at each measured point, slices to stem analysis were cut. If considered the age, a group of 649 trees between 8 to 30 years old resulted of the analysis. From this group, 50 trees were selected at random of each pmf class to modeling. The trees were grouped in pmf by the number of change point of stem shape defined by the second derivative of the polynomial 5th. Degree 5th grad Polinon adjusted for each tree. The statistics of adjustment and precision, residuals graphics, bias (v), average difference (md), and difference of standard deviation (dpd) showed as better model the polynomial 5th. degree to predict the diameter at relative height of stem, and alternatively the Garay model and the Max-Burkhart with two segments or modify to one segment according to the number of pmf calculated by the derivative.

Based on the Fe60Cr8Nb8B24 alloy, reported in the literature as good Glass Forming Ability (GFA), in this study the GFA of two new compositions was proposed, Fe68-xCrxNb8B24 (x=10,12). They were evaluated as good candidates to be new compositions of Bulk Metallic Glasses (BMG) with better corrosion resistance due to the high Cr content. Rapidly solidified glassy ribbons were processed, and based on their thermal characteristics, the critical thickness of the glassy structure formation (Zc) was estimated. The critical thickness (Zc) obtained experimentally using the wedge-shaped casting method was evaluated and it presented a much lower value than that estimated theoretically. However, the GFA of the compositions analyzed was ranked and this ranking (i.e. whichever has the most or least GFA) is in agreement with the result predicted theoretically. The GFA of Fe58Cr10Nb8B24, which presented a maximum thickness of the amorphous region of wedge-shaped samples of about 0.6 mm (but estimated it would be 3.56 mm), offered good prospects to be a new Fe-based glass former alloy which has better resistance to corrosion than the Fe60Cr8Nb8B24 alloy reported.