Embrapa Agroenergia


Embrapa Agroenergia

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Valadares L.F.,Embrapa Agroenergia
Applied Adhesion Science | Year: 2015

The human evolution is directly associated to the use of materials. During the last century, humanity had significant development powered by the use of fossil resources, which largely impacted the materials discovery and use. However, there are many concerns about the use of fossils, based mainly on economic and environmental issues. These concerns motivate the study, development, and use of renewable resources, including biobased materials. Brazil is one of the largest producers of agricultural commodities, which can be used to produce renewable materials. This review describes actual production of some renewable materials in Brazil and future possibilities to generate them using biomass residual streams of industrial processes. © 2014, Valadares; licensee Springer.

Laviola B.G.,Embrapa Agroenergia | Rodrigues E.V.,Embrapa Agroenergia | Teodoro P.E.,Federal University of Viçosa | Peixoto L.D.A.,Federal University of Viçosa | Bhering L.L.,Federal University of Viçosa
Renewable and Sustainable Energy Reviews | Year: 2017

Due to shortages of fossil fuels, and the worldwide concern approximately climate change and global warming, biofuels have become an important source of sustainable energy. Several species can be used to produce biofuels such as soybeans (Glycine max), oil palm (Elaeis guineensis), and Jatropha (Jatropha curcas L.). Therefore, the objective of this paper was to integrate the information available in the literature and report the most promising strategies for genetic and biotechnological progress in Jatropha. Jatropha has become a potential crop to produce biofuel due to the high oil content found in the seeds, which can be transformed into biofuel. Jatropha has an average seed oil content of 35%, and the oil extracted from the seeds has 24.6% crude protein and 47.2% crude fat. Moreover, Jatropha has several agronomic morphological traits that make it a useful crop for biofuel production and animal feed, such as drought tolerance, rapid growth, and ease of propagation. It can be grown at almost any altitude, and plants can produce for more than 50 years. Additionally, Jatropha oil has good stability to oxidation, low viscosity, a low pour-point, which makes Jatropha oil better than soybean or palm oil. This paper presented an innovative and comprehensive literature review on all agronomic aspects of Jatropha, and the strategies that have been used to select superior genotypes for Jatropha breeding. Several important traits of Jatropha are affected by the environment and new strategies to select superior genotypes are required by breeders. Therefore, genomic wide selection associated with recurrent selection can be an appropriate strategy for Jatropha breeding. © 2017 Elsevier Ltd

do Amaral J.F.T.,Federal University of Espirito Santo | Martinez H.E.P.,Federal University of Viçosa | Laviola B.G.,Embrapa Agroenergia | Filho E.I.F.,Federal University of Viçosa | Cruz C.D.,Federal University of Viçosa
Ciencia Rural | Year: 2011

To elucidate the differences in the nutritional requirements among the cultivated varieties of plant species is a form of obtaining higher productivity and to optimize the fertilizer use. This work had as objective to evaluate the root and shoot production efficiency of four arabic coffee cultivars ('Acaiá IAC 474-19', 'Icatú Amarelo IAC-3282', 'Rubi MG- 1192' and 'Catuaí Vermelho IAC 99') per unit of N, P, K, Ca, Mg, S, B, Cu and Zn absorbed. For this purpose an experiment was carried out in field conditions at the Universidade Federal de Viçosa. The treatments were settled in a 4x3 factorial arrangement (four cultivars and three fertilization levels; low, normal and high) in randomized blocks with four replications. The plants of the normal fertilization level received fertilization based on previously determined coffee plant recruitment. The plants of the levels low and high received, respectively, 0.4 and 1.4 times the normal fertilization doses. The efficiency of production of roots was differentiated among them cultivate when there was restriction in the amount of supplied fertilizers (low level), did not have differences among them when normal and high dose of fertilizers was used. When cultivate in the low fertilization level 'Acaiá IAC 474-19' presented highest efficiency to the production of roots per unit of N, P, K, Ca Mg and S absorbed, while in the some condition 'Rubi MG-1192' presented the smallest. It was concluded that efficiency of utilization of nutrients for root and shoot productions were differentiated among cultivars.

Pereira M.D.,Federal University of Viçosa | Filho S.M.,Federal University of Viçosa | Laviola B.G.,Embrapa Agroenergia
Pesquisa Agropecuaria Tropical | Year: 2012

Jatropha curcas L. is an oleaginous plant that has distinguished itself by presenting the qualities necessary to the biodiesel production. This study aimed to adjust the accelerated aging test methodology to evaluate the physiological potential of Jatropha curcas seeds. For this, four seeds lots were initially characterized by water content, germination percentage and first counting, seedlings emergence percentage and speed index, low temperature germination, and shoot height. The treatments included three temperatures (41 oC, 42 oC, and 45 oC) and four seeds exposure times (24, 48, 72, and 96 hours), in about 100% relative humidity. The accelerated aging test carried out for 24 hours, at 41 oC, was efficient for evaluating the Jatropha curcas vigour seeds, allowing to classify lots according to vigour levels, similarly to the germination first counting tests, seedlings emergence, low temperature germination, emergence speed index, and shoots height.

Rosado A.M.,Celulose Nipo Brasileira | Rosado T.B.,Embrapa Agroenergia | Alves A.A.,Embrapa Agroenergia | Laviola B.G.,Embrapa Agroenergia | Bhering L.L.,Federal University of Viçosa
Pesquisa Agropecuaria Brasileira | Year: 2012

The objective of this work was to estimate genetic parameters and to determine the efficiency of the simultaneous selection of eucalyptus clones based on yield, stability, and adaptability. Twenty-one clones, with 36 months of age, from the genetic breeding program of the company Cenibra were used. The experiment was done in a randomized complete block design, in four environments, with 21 replicates of one plant per plot. The clones were evaluated as to the variables: diameter at breast height, plant height, and total volume with bark. The genetic parameters were estimated using the mixed model procedure (REML/BLUP), and selection was based on the harmonic mean of the relative performance of the genetic values (HMRPGV), with three strategies: selection based on the predicted genetic gain, considering the average performance of genotypes in all environments (without interaction effect) or the performance on each environment (with interaction effect); and simultaneous selection based on productivity, stability, and adaptability. Environment particularities influenced the phenotypic expression of the clones. The heritability estimates indicated good perspectives for selecting clones with high yield, stability, and adaptability. Simultaneous selection optimizes clone selection and can be used in the construction of breeding populations and in the recommendation of genetic materials for commercial plantations.

Laviola B.G.,Embrapa Agroenergia | Rosado T.B.,Embrapa Agroenergia | Bhering L.L.,Federal University of Viçosa | Kobayashi A.K.,Embrapa Meio Norte | de Resende M.D.V.,Embrapa Florestas
Pesquisa Agropecuaria Brasileira | Year: 2010

The objective of this work was to estimate the genetic parameters and variability among accessions (half-sib families) of physic nut (Jatropha curcas) during the early stages of development. For this study, 110 accessions in the first year of development of the physic nut germplasm bank, maintained at Embrapa Cerrados, DF, Brazil, were evaluated in situ. The experiment was established in a randomized complete block design, with two replicates and five plants per plot arranged in rows at 4x2 m spacing. Grain yield, total number of branches per plant, plant height, stem diameter, canopy projection on the row, canopy projection between rows, canopy volume, number of days until first flowering and height of the first inflorescence were evaluated. Estimates of vegetative genetic parameters showed the existence of genetic variability in the physic nut germplasm bank. Physic nut accessions of the germplasm bank were grouped into five similarity groups based on character divergence. Although preliminary, the obtained results are promising for showing potential for Jatropha improvement with selective efficiency.

Vaz B.G.,Pontifical Catholic University of Rio de Janeiro | Vaz B.G.,Federal University of Goais | Abdelnur P.V.,Embrapa Agroenergia | Rocha W.F.C.,National Institute of Metrology of Brazil | And 2 more authors.
Energy and Fuels | Year: 2013

Crude oil samples are uniquely complex because of the number of compounds present that can only be resolved using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The FT-ICR MS technique has been redefined for examining the composition of crude oil and its products, which has led to a new field called "petroleomics". The chemical composition ultimately determines the chemical and physical properties and the behavior of petroleum and its products. "Petroleomics" predicts the properties and behavior of petroleum using its composition to solve production and processing problems. This paper correlates the chemical composition of crude oil with the total acid number (TAN), which enables the development of prediction models using partial least squares (PLS) and support vector machines (SVMs) as alternative multivariate calibration methods that allow for the application of FT-ICR MS analysis in direct measurements. The prediction models using PLS and SVM demonstrated low prediction errors and superior performance in relation to the univariate method. These results support the development of robust models to predict crude oil properties based on the vast quantity of information provided by FT-ICR MS using PLS and SVM as multivariate calibration procedures. © 2013 American Chemical Society.

Andreani L.,Embrapa Agroenergia | Rocha J.D.,Embrapa Agroenergia
Brazilian Journal of Chemical Engineering | Year: 2012

This paper discusses the feasibility of the use of ionic liquids as catalysts in the biodiesel production field, describing some studies already published in the literature on this theme. Ionic liquids are regarded as a new generation of catalysts in the chemical industry, with several uses in different commercial segments. However only a few publications involving this topic can be found in the literature addressing the manufacture of biodiesel from vegetable oils or animal fats. Through the analysis of the data generated in the studies reviewed, it is possible to affirm that ionic liquids present great potential as catalysts for biodiesel production, but there are some challenges to be faced, such as the production of ionic liquids with low cost, easy recovery and with the possibility of reutilization of the catalyst for several cycles.

Alvim H.G.O.,University of Brasilia | De Lima T.B.,University of Campinas | De Oliveira H.C.B.,University of Brasilia | Gozzo F.C.,University of Campinas | And 4 more authors.
ACS Catalysis | Year: 2013

Bronsted and Lewis acid catalysts with ionic tags under homogeneous and heterogeneous conditions have been tested to perform the Biginelli synthesis of 3,4-dihydropyrimidin-2(1H)-one (DHPMs). Metal-containing ionic liquids were evaluated as the catalysts with reasonable results (homogeneous systems). Heterogeneous catalysts (zeolite β and H3PW12O 40 supported on zeolite β) have been tested, as well, with good to excellent results. The use of a functionalized acid ionic liquid with a heteropolyacid in the anion moiety (homogeneous system) gave the best results using no excess of the three reagents. The preferred mechanistic pathway was investigated by electrospray ionization (tandem) mass spectrometry in both positive and negative ion modes with very elucidative results. The ionic liquid effect and its origin were also investigated using mass spectrometry and DFT calculations. © 2013 American Chemical Society.

Rocha R.B.,Embrapa Rondonia | Ramalho A.R.,Embrapa Rondonia | Teixeira A.L.,Embrapa Rondonia | Laviola B.G.,Embrapa Agroenergia | And 2 more authors.
Pesquisa Agropecuaria Brasileira | Year: 2012

The objective of this work was to estimate the genetic parameters of physic nut (Jatropha curcas) grain quality traits and to quantify the genetic progress with selection. Seed oil content, and seed, kernel, and shell weights of 120 plants, randomly selected in a commercial planting, were evaluated at 36 and 48 months. Genetic progress was quantified by the evaluation of direct gains and by the use of selection indexes. The genotype x measurement interaction was significant for all evaluated traits; therefore, there are genotypes with different behavior in the two cropping seasons. The genetic parameters indicated a higher proportion of genotypic variation in the expression of the evaluated traits, and a trend of the genotypes to maintain their genetic superiority over time was observed. The genotype-ideotype selection index resulted in higher genetic gains and promoted a more balanced alteration in the trait means. The direct selection for kernel weight results in genetic gains similar to those obtained with the use of the selection indexes.

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