Desenvolvimento de tecnologia de pré-polímeros na síntese de poliuretanos empregados em combustíveis sólidos

The aim of this work was to synthesize a polyurethane polymer matrix using polyols as a raw material to obtain a binder such as the hydroxyl terminated polybutadiene (HTPB) pre-polymer in energetic material formulation. The soybean-based polyol was the best starting raw material for producing a binder for solid fuel formulation in rocket motor applications. Characterization of the obtained soybean-based polyurethane binder was carried out by employing FT-IR analysis and thermo analytical techniques that showed similar HTPB binder thermo decomposition behaviors, confirming their potential for use as polymer matrix composites.

ISOLATION AND CHARACTERIZATION OF NANOFIBRILLATED CELLULOSE FROM OAT HULLS

The objectives of this work were to investigate the microstructure, crystallinity and thermal stability of nanofibrillated cellulose obtained from oat hulls using bleaching and acid hydrolysis at a mild temperature (45 ºC) followed by ultrasonication. The oat hulls were bleached with peracetic acid, and after bleaching, the compact structure around the cellulosic fibers was removed, and the bundles became individualized. The extraction time (30 or 60 min) did not affect the properties of the nanofibrillated cellulose, which presented a higher crystallinity index and thermal stability than the raw material (oat hulls). The nanocellulose formed interconnected webs of tiny fibers with diameters of 70-100 nm and lengths of several micrometers, producing nanofibers with a relatively high aspect ratio, thus indicating that these materials are suitable for polymer reinforcement.

GLICEROFOSFOLIPÍDIOS SINTÉTICOS PARA USO COMO ADITIVO BIOCIDA EM TINTAS ANTI‑INCRUSTANTE

AbstractThis paper presents a technological innovation that uses a subclass of glycerophospholipids as a booster biocide in antifouling paint. These glycerophospholipid PAF-analogs are economically and environmentally viable compounds because they are synthesized from a metal-free raw material source-soybean lecithin. The synthesis, which involves transesterification followed by an alkylation reaction, produced a mixture of glycerophospholipids that were characterized by mass spectrometry. Evaluation of the antifouling performance with field tests showed that the replacement of ordinary halogenated booster biocide with the synthesized product gave a better efficiency and an exceptional antifouling activity with a significant reduction in the coverage of the fouling macro-organisms.

Thermoanalytical study and characterization of native starches of Paraná pine seeds (Araucaria angustiofolia, Bert O. Ktze) and European chestnut seeds (Castanea sativa, Mill)

Starch is the most important carbohydrate storage in plants. It is a raw material with diverse botanical origins, and is used by the food, paper, chemical, pharmaceutical, textile and other industries. In this work, native starches of Paraná pine seeds (pinhão) (Araucária angustiofolia, Bert O. Ktze) and european chestnut seeds (Castanea sativa, Mill) were studied by thermoanalytical techniques: thermo-gravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC), as well as X-ray powder patterns diffractometry. Apparent and total amylose content was also determined.

Bleached kraft pulp production from Pinus tecunumanii (Eguiluz e Perry)

The use of 12-year-old Pinus tecunumanii (Eguiluz e Perry) grown in Colombia was evaluated for bleached kraft pulp production. Kraft pulps of kappa number 30 ± 1 were produced, and oxygen delignified and bleached to 90% ISO with ECF processes. The bleached pulps produced under optimum conditions were evaluated with regard to their strength properties. Pinus tecunumanii wood required low effective alkali charge to reach the desired kappa number and the unbleached pulp showed high oxygen delignification efficiency and bleachability when a OD(EO)DED sequence was used. The bleached pulps presented good physical-mechanical properties, which are comparable to those obtained with more traditional pines such as Pinus taeda and Pinus radiata. The results demonstrate that this tropical pine species is a suitable raw material for bleached kraft pulp production

Extractives and energetic properties of wood and charcoal

Charcoal production stands out as a raw material for the production of renewable energy. To assess wood quality in energy terms, studies have focused more on the holocellulose and lignin content than on the role of extractives. The objective of this study was to evaluate the relationship between the extractive content in cold water, in dichloromethane and total on energy properties of wood and charcoal, from six trees species. The extractives were removed with different solvents to be recorded and gross calorific value of wood was determined. The wood was carbonized at 1.67°C/min heating rate until maximum of 450°C and residence time of 30 min. The extractive content was correlated with the gravimetric yield, apparent relative density, ash, volatile matter, fixed carbon and gross calorific value of charcoal. The removal of total extractives and extractives soluble in dichloromethane reduced the gross calorific value of wood of most species evaluated. The extractives removed in cold water did not correlate with the parameters of carbonization. The extractives content in dichloromethane correlated with volatile matter, fixed carbon and gross calorific value. Total extractive content correlated with gravimetric yield, apparent relative density and gross calorific value of charcoal.

COMPARISON BETWEEN WOOD DRYING DEFECT SCORES: SPECIMEN TESTING X ANALYSIS OF KILN-DRIED BOARDS

It is important to develop drying technologies for Eucalyptus grandis lumber, which is one of the most planted species of this genus in Brazil and plays an important role as raw material for the wood industry. The general aim of this work was to assess the conventional kiln drying of juvenile wood of three clones of Eucalyptus grandis. The specific aims were to compare the behavior between: i) drying defects indicated by tests with wood specimens and conventional kiln-dried boards; and ii) physical properties and the drying quality. Five 11-year-old trees of each clone were felled, and only flatsawn boards of the first log were used. Basic density and total shrinkage were determined, and the drying test with wood specimens at 100 °C was carried out. Kiln drying of boards was performed, and initial and final moisture content, moisture gradient in thickness, drying stresses and drying defects were assessed. The defect scoring method was used to verify the behavior between the defects detected by specimen testing and the defects detected in kiln-dried boards. As main results, the drying schedule was too severe for the wood, resulting in a high level of boards with defects. The behavior between the defects in the drying test with specimens and the defects of kiln-dried boards was different, there was no correspondence, according to the defect scoring method.

Adaptation of "Niagara Rosada" grape must to winemaking by partial cluster dehydration

This study aimed to verify the influence of partial dehydration of "Niagara Rosada" grape clusters in physicochemical quality of the pre- fermentation must. In Brazil, during the winemaking process it is common to need to adjust the grape must when the physicochemical characteristics of the raw material are insufficient to produce wines in accordance with the Brazilian legislation for classification of beverages, which establishes the minimum alcohol content of 8.6 % for the beverage to be considered wine. Therefore, given that the reduction in the water content of grape berries allows the concentration of chemical compounds present in its composition, especially the concentration of total soluble solids, we proceeded with the treatments that were formed by the combination of two temperatures (T1-37.1ºC and T2-22.9 ºC) two air speeds (S1: 1.79 m s-1 and S2: 3.21 m s-1) and a control (T0) that has not gone through the dehydration treatment. Analysis of pH, Total Titratable Acidity (TTA) were performed in mEq L-1, Total Soluble Solids (TSS) in ºBrix, water content on a dry basis and Concentration of Phenolic Compounds (CPC) in mg of gallic acid per 100g of must. The average comparison test identified statistically significant modifications for the adaptation of must for winemaking purposes, having the treatment with 22.9 ºC and air speed of 1.79 m s-1 shown the largest increase in the concentration of total soluble solids, followed by the second best result for concentration of phenolic compounds.

Economic analysis for sizing of sugarcane (Saccharum spp.) mechanized harvesting

Sugarcane has a significant role on Brazilian agribusiness economy. The harvesting cane is considered as one of the most important operations of the process for it has to attend the raw material demanded by the sugar mill in quality and a competitive cost. The objective of this work it is it of analyzing, of systemic way, the variables influence on economical and operational performance in sugarcane mechanized harvesting process for sizing of machines. For this purpose a model called "ColheCana", was developed in a spreadsheet and in a programming language. The results showed that the field efficiency and harvester´s initial value are variables of great impact in the cost and that there is a maximum area that one equipment can attend and for this area the cost is minimum.

Yam (Discorea sp) drying with different cuts and temperatures: experimental and simulated results

The yam (Discorea sp) is a tuber rich in carbohydrates, vitamins and mineral salts, besides several components that serve as raw material for medicines. It grows well in tropical and subtropical climates and develops well in zones with an annual pluvial precipitation of around 1300mm, and with cultural treatments, its productivity can exceed 30t/ha. When harvested, the tubers possess about 70% of moisture, and are merchandised "in natura", in the atmospheric temperature, which can cause its fast deterioration. The present work studied the drying of the yam in the form of slices of 1.0 and 2.5cm thickness, as well as in the form of fillets with 1.0 x 1.0 x 5.0cm, with the drying air varying from 40 to 70°C. The equating of the process was accomplished, allowing to simulate the drying as a function of the conditions of the drying air and of the initial and final moisture of the product. Also investigated was the expense of energy as function of the air temperature. The drying in the form of fillets, with the air in a temperature range between 45 and 50°C, was shown to be the most viable process when combining both the quality of the product and the expense of energy.

Nutritional aspects of nile tilapia (Oreochromis niloticus) silage

One third of the world's fishing produce is not directly used for human consumption. Instead, it is used for making animal food or is wasted as residue. It would be ideal to use the raw material thoroughly and to recover by-products, preventing the generation of residues. With the objectives of increasing the income and the production of the industry, as well as minimizing environmental and health problems from fish residue, chemical silage from Tilapia (Oreochromis niloticus) processing residues was developed after homogenization and acidification of the biomass with 3% formic acid: propionic, 1:1, addition of antioxidant BHT and maintenance of pH at approximately 4.0. Analyses to determine the moisture, protein, lipids and ash were carried out. The amino acids were examined in an auto analyzer after acid hydrolysis, except for the tryptophan which was determined through colorimetry. The tilapia silage presented contents that were similar to or higher than the FAO standards for all essential amino acids, except for the tryptophan. The highest values found were for glutamic acid, lysine and leucine. The results indicate a potential use of the silage prepared from the Nile tilapia processing residue as a protein source in the manufacturing of fish food.

Fatty acids and nutrients in the flour made from tilapia (Oreochromis niloticus) heads

The objective of this work was to analyze the fatty acid composition and nutrient potential of flour made from tilapia heads, which are normally discarded during the filleting operation. Significant differences were found between the proximate composition (moisture, ash, protein and total lipids) of the in natura tilapia and the flour, due to the drying process. The predominant fatty acids in the heads (in natura and in the flour) were palmitic acid (1,999 mg.100 g-1 and 7,699 mg.100 g-1, respectively), oleic acid (3,128 mg.100 g-1 and 11,447 mg.100g-1, respectively), and linoleic acid (1,018 mg.100 g-1 and 3,784 mg.100 g-1, respectively). The results lead us to conclude that tilapia head flour offers high levels of protein (38.41%), total lipids (35.46%), and ash (minerals) (19.38%). The content of omega-3 (731 mg.100 g-1) were proved to be satisfactory. Also, n-6/n-3 ratio was 6.15 and PUFA/SFA ratio was 0.47, which are in agreement with the recommended levels. Thus, tilapia heads can be used as a low-cost raw material for food fit for human consumption.

Functional extruded snacks with lycopene and soy protein

In this work, the effects of thermoplastic extrusion process parameters (raw material moisture content and temperature) and the addition of functional ingredients (lycopene and soy protein) on quality characteristics of a base-formulation for extruded corn snacks were studied, with the objective of developing an easy-to-eat functional product. A single-screw Labor PQ 30 model Inbramaq extruder was used for extrusion and a central composite rotational design (CCRD) was followed. The independent variables were: i) percentage of soy protein isolate (0-30%); ii) percentage of lycopene preparation (0-0.1%); iii) raw material moisture content (20-30%); and iv) 5th zone temperature (100-150 °C). The expansion index reached maximum values with the lowest raw material moisture content (20%) and intermediate temperatures (approximately 125 °C). Instrumental hardness was higher with high moisture and low temperature; however, increasing the percentage of soy protein was beneficial for the texture of the product, reducing hardness. The red color intensity increased with the increase in lycopene content and moisture, and with the reduction of temperature. Sensory acceptance tests were carried out for two products, with maximum percentages of the functional ingredients, 20% moisture and temperatures of 125 and 137 °C, with greater acceptance for the product extruded at 125 °C.

Microorganisms screening for limonene oxidation

Limonene is a monoterpene obtained in large amounts from essential oils and is used as a raw material for the synthesis of flavors and fine chemicals. Several pathways or routes for the microbial degradation of limonene making use of the cytochrome P450-dependent monooxygenases have been described. In this study, we present a fermentative screening of microorganisms in order to verify their ability to perform the desirable conversion. In parallel, the PCR technique was used to select the microorganisms that contain the limC gene, which is responsible for the conversion of carveol to carvone. The microorganisms selected by PCR were not able to bioconvert limonene. From this result, we can suppose that these strains do not have the gene that codifies the enzyme responsible for the transformation of limonene into carveol. The results obtained in the fermentative screening showed that 4 microorganisms were able to bioconvert limonene into carveol. In addition, the amplification results showed the presence of fragments of 800 pb, expected for the limC gene. Therefore, the results obtained in the bioconversion and evaluation of the limC gene did not allow a correlation showing that these strains do not contain all the enzymes responsible for the conversion of limonene to carvone.

Chemical composition of five loquat cultivars planted in Brazil

Loquat is a fruit with high market value cultivated in Southeast Brazil. Despite of this, there are little details about its quality characteristics. Fruits from five loquat cultivars, developed using genetic breeding, were analyzed to assess their compositional traits. The cultivars Centenária, Mizuho, Mizumo, Néctar de Cristal and Mizauto were selected based on their high productivity and resistance to diseases. Soluble sugars, organic acids, and carotenoids were quantified using liquid chromatography. The cultivar (cv.) with the highest total sugar concentration was Mizumo and the lowest concentration was found in Centenária. The main sugar detected was sucrose, and the malic acid was the major organic acid. Ascorbic acid was detected in small amounts. The total dietary fiber contents were almost the same in all cultivars. The major carotenoids detected were β-carotene and β-cryptoxanthin, except for the cultivar Nectar de Cristal, a white pulp loquat. These results contribute to the knowledge about de physiology of loquat fruit, an interesting raw material due to its nutritional and sensorial characteristics. Furthermore, the results obtained could help to identify the most appropriate use of the loquats with different attributes either for consumption in natura or for industrial processing.