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In the present work, cagaite (Eugenia dysenterica DC.) seed oil was studied as a potential inedible raw material for biodiesel production. The oil was extracted using a Soxhlet extractor and the fatty acids acyl esters that make up biodiesel were obtained by alkaline transesterification using sodium hydroxide. The influence of reaction parameters was also evaluated: molar ratio, time, and amount of catalyst. The conversion of fatty acids into fatty acid methyl esters (FAME), which make up biodiesel, was calculated using Nuclear Magnetic Resonance Spectroscopy (1HNMR) spectra. In a 30 min reaction period, the molar ratio of oil to methanol was 1:4, resulting in a conversion of 63.57%. However, when the molar ratio was increased to 1:8, the conversion reached 81.74% during the same 30 min reaction period. After 60 min of reaction, additional increases in conversion were observed when molar ratios of 1:4, 1:6, and 1:8 were used. Under these conditions, the conversions achieved were 92.08%, 98.24%, and 98.78%, respectively. The physico‐chemical properties were evaluated and the results showed that cagaite seed oil biodiesel was similar to soybean biodiesel, which is the most commonly produced biodiesel in Brazil. It was thus an important substitute for soybean biodiesel. [ABSTRACT FROM AUTHOR]

In this study, to give a new final disposal to the Dredged Sediments (DS) in the Port of Rio Grande, the manufacture of Compressed Earth Blocks (CEB) with the addition of alkali-activated cement (AAC) is proposed. This binder was produced by mixing Rice Husk Ash (RHA), Carbide Lime (CL), and Sodium Hydroxide Solutions (SHS). The methodology includes AAC optimization for the production of CEBs, considering their performance in terms of unconfined compressive strength (UCS), durability analysis by wetting and drying cycles, and the qualification of the blocks, according to strength and water absorption criteria. The results show that AAC is a satisfactory option to improve the mechanical performance of DS. After 28 days of curing, the CEBs pass the requirements established by the Brazilian standard NBR 8492 to be used in the execution of masonry without structural function in Brazil. [ABSTRACT FROM AUTHOR]

Sesbania punicea is a native plant of Brazil, has ornamental features inflorescences arranged in bunches of orange coloring. Its main form of propagation is through seeds, but these present integumentary dormancies, for which there is still no method of overcoming established. The objective of this study was to evaluate methods of breaking dormancy in S. punicea seeds for seedling production. The treatments used were control - no treatment, hand scarification with sandpaper grade 80 for 40 sec.; hand scarification with sandpaper grade 80 for 60 sec.; thermal treatment by soaking in water from 80°C to room temperature and chemical treatment - stirring in 0.5 L solution of 12% sodium hypochlorite (NaClO), 3 mL of hydrochloric acid (HCl) and 20 g of commercial sodium hydroxide (NaOH) dissolved in 1 L of water, for 45 min.). After the treatments, the seeds were wrapped in rolls of autoclaved germitest paper and moistened with distilled water 2.5 times the weight of the sheet. Then, the rolls were placed in plastic bags, stored in the upright position, and incubated at 25°C, in a 16 h photoperiod, for 14 days. A completely randomized design with four replications of 25 seeds was used. The germination percentage, average germination time, germination speed index, percentage of normal seedling formation, shoot length, root system length and percentage of hard seeds were evaluated. There was a difference for all the analyzes evaluated, except for the length of the aerial part. The dormancy breaking method through mechanical scarification using sandpaper for 60 sec., enables the propagation and formation of S. punicea seedlings. [ABSTRACT FROM AUTHOR]

In Brazil, the growth of Tectona grandis (teak) plantations is accompanied by an increased incidence of Ceratocystis wilt, a fungal disease that colonizes the vascular system of such tree. The objective of this work was to evaluate the properties of teak wood infected with Ceratocystis fimbriata at different radial positions. Ten 17-year-old trees (five infected and five healthy) were collected. A disk was removed from the base of each tree to determine Janka hardness, basic density, anatomical analysis, colorimetric parameters in the CIEL*a*b* system and sodium hydroxide solubility (NaOH). There were no significant differences for radial position and health for basic density and Janka hardness of the wood, with mean values of 0.488 g.cm3 and 58.66 MPa, respectively. The deposition of dark compounds was observed inside the parenchyma cells and fibers, as well as the formation of tyloses in the sapwood. Yellow pigment was predominant in the color formation of teak wood, which was influenced by radial position, with the sapwood being lighter. Regarding C. fimbriata infection, the color change was more evident in sapwood. Conversely, the NaOH solubility was lower for the sapwood attacked by the fungus. In conclusion, the changes in teak wood infected by C. fimbriata are visual and the anatomical structures do not deteriorate. [ABSTRACT FROM AUTHOR]

This work aimed to determine efficient methods for dormancy breaking in Dimorphandra mollis Benth seeds. The seeds were collected from mother trees in the municipality of Buriti, Maranhão State, Brazil. They were submitted to the following treatments: control (T1); mechanical scarification with sandpaper No. 60 (T2); chemical scarification with 98% lye (sodium hydroxide) for 15 min (T3); chemical scarification with sulfuric acid 99.9% for 20 min (T4) and thermal-shock with water (T5). In a greenhouse, we used 16 seeds per treatment, divided into four replications, in a completely randomized design. The evaluations started on the third day after seeds were treated and it was carried out until 17 days after sowing. The percentage of emerged seeds and the emergence speed index were evaluate. The mechanical scarification treatment with sandpaper (T2) and the chemical scarification with sulfuric acid (T4) were efficient to overcome the seed coat impermeability, but the mechanical scarification is the safest method for users to overcome seed dormancy. [ABSTRACT FROM AUTHOR]

The dwarf-green coir fibers treated with sodium hydroxide 10% produced the best set of properties of the biocomposites generated: greater roughness and exposure of intrafibrillar cavities, providing better adhesion with the matrix, higher rigidity, increased resistance to traction and better interface properties, making them better as structural materials. The best results reported in the thermal behavior of biocomposite fibers were found in fibers treated with sodium hydroxide 10%. These showed a single stage of decomposition, which occurs at a higher temperature (300°C). It was observed that the natural fibers were more resistant to the action of the microorganisms due to the presence of more lignin and hemicellulose, while fibers treated with 5 and 10% sodium hydroxide showed different degradation degree. [ABSTRACT FROM AUTHOR]

During the poultry industrialization process the so-called sludge oil, a residual chicken fat, is recovered in the wastewater treatment plant and its use presents potential as raw material for biodiesel production. Thus, the aim of the study was to prepare blends of sludge oil with soybean oil to obtain fatty acid methyl esters (FAME) through the homogeneous alkaline transesterification reaction. To perform this study, a simple pre-treatment process - heating and subsequent filtration - was used, allowing sludge oil to be mixed with soybean oil to compose blends, without the need to use more sophisticated pre-treatment processes. After this step, blends ranging from 5% to 90% (m/m) of sludge oil mixed with soybean oil were prepared. The results showed that the molar ratio (1:6 oil blend:methanol), catalyst concentration 0.5% NaOH (m cat /m oil ), at 65 °C for 60 min yielded FAME above 99.0 and 90.0% (m/m) for blends with up to 5 and 15% sludge oil, respectively. By increasing the temperature to 70 °C, under the same selected parameters, the blend with 10% sludge oil provided yield above 99.0% (m/m), presenting appropriate physicochemical properties, within the parameters required by National Agency of Petroleum, Natural Gas and Biofuels (ANP). These findings show the great potential sludge oil provides to reduce Brazil's dependency on soybean oil for biodiesel production. Highlights Sludge oil, a waste raw material for biodiesel production, is not yet explored in Brazil.A procedure for biodiesel production using soybean oil and sludge oil blends was proposed.The best reaction condition was 1:6 oil blend:MeOH molar ratio; 0.5% NaOH (m cat /m oil ), at 70 °C for 60 min.Biodiesel yield was higher than 99% (m/m) under optimal reaction conditions.Sludge oil represents a promising waste raw material for biodiesel production.

The hydrozoan Cordylophora caspia, with its origin in the Caspian and Black Seas, is considered an invasive biofouling species to power stations and water treatment plants in Brazil, causing economic and ecological impacts. Tolerance of the species to variation in pH was tested to evaluate its resistance to acidic and basic pH levels. Values of pH were tested over a range from 4.0 to 10.0. The colonies were exposed for 6 h to each treatment, using phosphoric acid and NaOH to set water pH to the desired acidic or basic levels, respectively. Colonies of C. caspia displayed 100% mortality only at pH 4 and 10, and showed high survival rates (>50%) within the pH range of 5.0-8.5. The species demonstrated tolerance to a wide range of pH levels, and the results will help in the development of techniques to reduce biofouling by this species. Treatments that keep the pH below 5 or above 8.5 for at least 6 h are suggested to control and eradicate C. caspia where fouling causes significant economic impacts. [ABSTRACT FROM AUTHOR]

Production of kaolin for the paper-coating industry in the Brazilian Amazon region generates large amounts of waste, most of which is kaolinite. It is known that such materials can be used to synthesize zeolites. The use of kaolin waste for zeolite synthesis could, in principle, help social and economic development while providing valuable materials for industry. Additionally, there is a significant environmental appeal if such wastes could be used instead of new raw materials.This study focused on the production of zeolite A. Samples of the raw material were first calcined (700ºC/2 h) to obtain metakaolinite for further reaction with NaOH solution. Different parameters were evaluated to optimize the synthesis conditions of zeolite A. The results showed that zeolite A with a large degree of structural order was generally obtained as the only zeolitic product. The following synthesis conditions were used: temperature 110ºC, time 24 h and a Na/Al ratio of 1.36. Hydroxysodalite was also obtained under specific conditions. [ABSTRACT FROM AUTHOR]

Abstract: Cupuassu (Theobroma grandiflorum, Schumann) is a Brazilian Amazonian fruit whose pulp contains volatile compounds that have been extensively studied. In this work, the pulp from fruits of cupuassu was ground, treated with MeOH–H2O, and defatted with p-Tol–EtOH. The residue (4% in relation to the fresh pulp) was submitted to sequential extractions with water, aqueous citric acid and aqueous NaOH, resulting in polysaccharide fractions with 0.3–15% yield. The main pectic fraction (7% yield) was obtained with water at 25°C (W-1 fraction) and was chosen to be better characterized. Chemical and spectroscopic analyses showed that W-1 is composed mainly of a homogalacturonan highly esterified (DE 53%; DA 1.7%) with some rhamnogalacturonan insertions, carrying side chains containing galactose and arabinose. [Copyright &y& Elsevier]

With the evidence showing the protection variability of bacille Calmette-Guérin, new potential vaccines for tuberculosis have been tested around the world. One of the general concerns in tuberculosis vaccine development is the possibility of priming the host immune system with prior exposure to environmental mycobacteria antigens, which can change the efficacy of subsequent vaccination. As there is a great homology between the species from Mycobacterium genera, the previous contact of experimental animals with environmental mycobacteria could sensitize the mice and, in this way, could influence subsequent vaccine research. The aim of our study was to investigate critical points in an animal facility to search for environmental mycobacteria that eventually could be in direct or indirect contact with the experimental animals. Samples were collected from surfaces of walls, floor, animal cages and shelves and analysed using the Ogawa-Kudoh decontamination method. Samples of drinking water, food and sawdust were collected for analysis by the NALC/NaOH decontamination method. Also, the samples were cultivated directly in broth medium, without any method for decontamination. After decontamination methods, we observed bacterial colony growth in 4.31% of the total of samples analysed. These samples were stained with Ziehl-Neelsen and we did not detect any acid-fast bacilli, suggesting that the animal facility analysed is free from contamination by environmental mycobacteria and is not a source of mycobacterial antigens. Furthermore, our study showed a new paradigm in tuberculosis vaccine development: concern about the animal facility environment in terms of immune system priming of experimental animals by nascent bacterial contaminants., (© 2009 Blackwell Verlag GmbH.)

The EU Directive 1999/77/EC, prohibiting new applications of chrysotile, exempted diaphragms used in electrolysis to produce chorine and caustic soda in existing chlor-alkali plants until they reach the end of their service life, or until suitable asbestos-free substitutes become available, whichever is sooner. There is no technical justification for extending this exemption after January 2008, when it is scheduled for review. Economic interests should not take precedence over the social and environmental costs imposed by the asbestos production required for this industry. The EU Scientific Committee on Toxicity, Ecotoxicity and the Environment should not further delay the necessary decision on a total and immediate worldwide ban of the mining, manufacturing, and all uses of asbestos.

Techniques to improve the sensitivity of smear microscopy would facilitate early tuberculosis (TB) diagnosis and disease control, especially in low-income countries where the positive predictive value is high. C(18)-carboxypropylbetaine (CB-18) is a zwitterionic detergent that helps to compensate for the innate buoyancy of mycobacteria, potentially enhancing recovery by centrifugation. Previous data suggest that CB-18 may increase the sensitivity of smear, culture, and molecular amplification diagnostic testing. The goal of the present study was to evaluate if the sensitivity of the smear technique using light microscopy could be improved by treating respiratory samples with CB-18. In the first phase, respiratory specimens were collected consecutively from patients with suspected pulmonary tuberculosis in a tertiary-care hospital in Rio de Janeiro, Brazil (236 specimens were analyzed). After protocol modifications, another 120 respiratory specimens were evaluated. The standard technique was N-acetyl-L-cysteine with sodium hydroxide (NALC-NaOH) treatment, smear concentration with centrifugation, and Ziehl-Neelsen staining. Culture on Löwenstein-Jensen slants was performed on all specimens for use as the "gold standard." No specimens from patients undergoing active TB treatment were included. The initial protocol for CB-18 processing resulted in a sensitivity of 59.6% and specificity of 96.8% compared to standard processing with a sensitivity of 66.0% and specificity of 96.8%. Using the modified protocol, the sensitivity of CB-18 increased to 71.4% with a specificity of 97.0% versus standard processing with a sensitivity of 61.9% and a specificity of 99.0%. The diagnostic yield of acid-fast bacillus smear with CB-18 in the absence of fluorescence microscopy and PCR compared to standard processing with NALC-NaOH was not significantly different, although the power to detect a difference by the modified assay was low.