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Thermal modification is a technique that can be used to increase the resistance of wood to the biodeterioration processes. In this context, the objective of this study was to evaluate the durability of Parkia pendula (angelim-saia) and Simarouba amara (marupá) woods thermally modified in rotting field tests and by the action of natural weathering. The tests were carried out in the Brazilian Amazon region, in the Mato Grosso State. The thermal modification of the wood was set with four treatments: control (T1); electric-oven treatment, 180°C for 3 h (T2); combination of autoclave and electric-oven, 125°C for 3 h, and 180°C for 3 h respectively (T3), and immersion in vegetable oil, 180°C for 3 h (T4). The samples were partially buried for the field rotting assays, and the mass loss and deterioration index were seasonally evaluated after the experiment was installed. These analyses were performed on the same samples which has been exposed to rotting essays. The action of natural weathering was assessed through the CIELAB* colour system. T4 was the most efficient for increasing the resistance to biological deterioration, under the tested conditions. T2 and T3 treatments conferred higher colorimetric stability for both types of woods after natural weathering, under the tested conditions. [ABSTRACT FROM AUTHOR]

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Alternative treatments to control ticks are being increasingly investigated, including natural products to decrease parasitic resistance and environmental impact. The present study investigated the chemical profile of eucalyptus wood vinegar and evaluated its effect on the reproduction of Rhipicephalus sanguineus. Eucalyptus wood vinegar (WV) was tested at several concentrations. For the experiment, 500 engorged females were collected from canine hosts. The female ticks were distributed by weight in groups of ten per WV concentration, with five replicates per treatment. For all tests, the ticks were immersed for 5 min in a solution with each WV concentration. The positive control was amitraz and negative was water. The major components of the WV's organic fraction were furfural and phenolic compounds. A significant decrease in egg hatching was observed in the WV concentration range from 65 to 1,000 mg mL−1. When parameters such as the percentage of hatching, female weight, and egg mass were evaluated, the efficiency of the product was verified as being between 84.97% and 99.38% in the concentration range of 65 to 1,000 mg mL–1, respectively. There is a real potential for using eucalyptus WV to control dog ticks since it negatively affects the reproductive cycle of the parasites. [ABSTRACT FROM AUTHOR]

Eucalyptus wood vinegar (WV) is a versatile natural product employed in several areas such as for agriculture, zootechnics, and veterinary applications. However, the product may contain contaminants such as polycyclic aromatic hydrocarbons, methanol, metals, and so on in its raw form. Thus, refining is required to remove them. Only after reaching a high-purity grade can WV be applied as a basis for pharmaceuticals, antimicrobials, and additives for animal husbandry. This work aimed to assess the effect of refining on the contaminant content of a WV produced on an industrial scale and traded as agricultural input in the Brazilian market. WV was refined by sequential vacuum distillations and had its contaminant contents assessed before and after refining. The following chemical classes were investigated: metals and other elements, insecticides, fungicides, and herbicides (carbamates, organochlorines, organophosphates, pyrethroids, and others), mycotoxins, polychlorinated dioxins and furans, polycyclic aromatic hydrocarbons, and volatile organic compounds, encompassing more than 100 chemical species. Also, the WV physical–chemical properties before and after refining were determined. Gas chromatography and mass spectrometry (GC/MS) were employed to attain the WV's chemical profile. The main chemical components, such as phenolic compounds, furans, ketones, pyrans, etc., were annotated in the WV chemical profile. No traces of insecticides, fungicides, herbicides, heavy metals, mycotoxins, polychlorinated dioxins, or polychlorinated furans were found in raw WV or refined versions. However, several other undes/irable chemicals were determined in the raw product, such as PAHs and volatile organic compounds (acetaldehyde, acetone, ethylene glycol, and methanol). Nevertheless, all of them were effectively removed from the raw WV after the first or second sequential refining steps, resulting in a pure product. Therefore, only one refining step can be applied to raw WV to yield a high-quality product for pharmaceutical and animal husbandry applications. [ABSTRACT FROM AUTHOR]

Charcoal is one of the most essential energy sources in the world and is used mainly for domestic and industrial purposes. Brazilian charcoal production occurs in rudimentary masonry kilns without concern for process safety or energy waste. This work aimed to develop a mini carbonization system of three kilns coupled to a vertical smoke burner for optimized and environmentally correct charcoal and wood vinegar (WV) production on small farms. The project was divided into three parts for dimensioning: the three-kiln set, the WV condensing device, and the smoke burner. The condenser was designed following the procedures from the standards of TEMA (Tubular Exchangers Manufacturers Association); ASME (Society of Mechanical Engineers of the United States) Section VIII, Division 1; and the NR-13 (Regulatory Standard) of ABNT (Brazilian Association of Technical Standards). In contrast to the current scenario, in which primitive carbonization technologies are still employed, bringing about low charcoal yields and significant pollution release, the use of a mini-kiln that allows charcoal production and wood vinegar recovery combined with pollutant smoke burning is an interesting eco-friendly solution. Thus, the mini-kiln model presented here brings a low cost and environmental safety to the charcoal production chain, reaching sustainability parameters and offering higher income opportunities to small producers. [ABSTRACT FROM AUTHOR]

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Pre-treatments reduce energy consumption for the production of cellulose micro/nanofibrils (MFC/CNF). The objective of this work was to study sodium silicate (Na2SiO3) solutions as pre-treatment for Eucalyptus sp. and Pinus sp. pulps. The treatments were identified as EUC SS 5 % and EUC SS 10 % when 5 and 10 % Na2SiO3 were used, respectively. The treatments for Pinus sp. pulp were identified as PIN SS 5 % and PIN SS 10 %, and the untreated pulps as EUC control and PIN control. The lowest hemicellulose content was obtained for PIN SS 10 %. EUC SS 10 % showed the highest WRV values. EUC SS 5 % (∼ 4100 kWh/t) and EUC SS 10 % (∼ 4200 kWh/t) showed the lowest energy consumption. The pre-treated MFC/CNF showed diameters below 45 nm. The lowest viscosity was obtained for EUC SS 5 % (5.5 cP) and the highest for PIN control (7.7 cP), respectively. The zeta potential indicated moderate stability of the suspensions (−24 ∼ −18 mV). Na2SiO3 showed efficiency for MFC/CNF production due to reduced energy consumption and better individualization. The suspensions have compatible characteristics for application as a stabilizer of colloidal systems and reinforcement of composites. [ABSTRACT FROM AUTHOR]

The present work evaluates the production of wood–cement particleboards (WCBs) with addition of coconut-husk fibers. Trees of a Eucalyptus urophylla × Eucalyptus grandis hybrid were used as wood source. Boards were produced with addition of five coconut-fiber levels (0%, 10%, 20%, 30%, 40% and 50%) to replace the original wood, in a completely randomized design. From each board, specimens were taken to perform physical–mechanical tests (density, water absorption, thickness swelling, static bending, compression strength, and internal bond strength). The chemical characterization of the coconut fiber – in particular the total amount of extractives – in cold and hot water and an organic solvent, along with determination of lignin, holocellulose and ash amounts. The results showed that the addition of coconut fibers significantly affected the physical–mechanical properties of the boards. For the physical properties, the addition of coconut fibers improved the dimensional stability with the respective decrease in water absorption and thickness swelling. For mechanical properties, a decrease in the MOR and MOE was observed as the percentage of coconut fibers increased, most likely due to a poor interaction between the particles and the cementitious matrix. The resulting WCBs were suitable for nonstructural and indoor uses. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work aimed to evaluated the effect of heat treatment on physical and mechanical properties of Hymenolobium petraeum Ducke wood. For this, were manufactured samples with 25.0 × 9.0 × 1.7 cm which were submitted to different heat treatments, with two temperatures (180 and 200 °C) and two exposure times (2 and 4 hours), besides the control samples (without the heat treatment). After the treatments, each sample were submitted to the assays with withdrawal of subsamples for the physical (density, mass loss, equilibrium moisture content and dimensional stability) and mechanical properties (static bending and compression parallel to grain). The heat treatment provided a weight loss of wood, with the higher temperature treatments displayed the greatest losses. However, it proved effective to decrease the equilibrium moisture content and the dimensional stability. The mechanical properties were not affected to the heat treatment. [ABSTRACT FROM AUTHOR]

The purpose of this research was to evaluate the potential of Artificial Neural Networks in estimating the properties of wood resistance. In order to do so, a hybrid of eucalyptus (Eucalyptus urograndis) planted in the Northern Region of the State of Mato Grosso was selected and ten trees were collected. Then, four samples of each tree were removed, totaling 40 samples, which were later subjected to non-destructive testing of apparent density, ultrasonic wave propagation velocity, dynamic modulus of elasticity obtained by ultrasound, and Janka hardness. These properties were used as estimators of resistance and compressive strength parallel to fibers, and hardness. Multilayer Perceptron networks were also employed, training 100 of them for each of the evaluated parameters. The obtained results indicated that the use of Artificial Neural Networks is an efficient tool for predicting wood resistance. [ABSTRACT FROM AUTHOR]

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este trabalho teve como objetivo determinar e avaliar o rendimento de madeira serrada de cambará (Qualea sp.) em diferentes classes de diâmetro. O estudo foi realizado em uma serraria localizada na região Norte do Estado de Mato Grosso, onde foram selecionadas sessenta toras, aleatoriamente, e agrupadas em quatro classes de quinze toras cada. As classes avaliadas foram: diâmetros inferiores a 55 cm (classe I); entre 55 e 65 cm (classe II), entre 65 e 75 cm (classe III) e diâmetros superiores a 75 cm (classe IV). Em média, observou-se cerca de 52% de rendimento para o cambará. Observou-se ainda que a classe diamétrica influenciou significativamente o rendimento do cambará, sendo a classe IV a que proporcionou maior rendimento. Entretanto, não se verificou tendência linear significativa para a relação entre estas variáveis e sim um comportamento parabólico, com os maiores percentuais de aproveitamento da madeira observados para a maior e menor classe avaliadas. This study aimed to determine and evaluate the diameter influence on lumber yielding of Qualea sp. The study was carried out in a sawmill in Mato Grosso State, Brazil. We selected randomly sixty logs that were grouped in four classes of fifteen logs each. The evaluated classes were: diameters smaller than 55 cm (class I); between 55 and 65 cm (class II); between 65 and 75 cm (class III) and diameters greater than 75 cm (class IV). Average yield of Qualea sp. was approximately 52%. It was also observed that the diameter class influenced significantly the performance of cambará, with class IV presenting the highest yield. However, there was no significant linear trend relationship between variables. It was observed a parabolic behavior, with higher yield percentages observed for the highest and lowest diameter classes. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Forest Research / Pesquisa Florestal Brasileira is the property of Brazilian Journal of Forest Research / Pesquisa Florestal Brasileira and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Wood Industry / Drvna Industrija is the property of Drvna Industrija and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The resistance of particleboards, made from wood, bamboo and rice husk, to fungi and termites was evaluated. Panels were composed of 100% wood (Eucalyptus grandis), 100% bamboo (Bambusa vulgaris), 100% rice husk (Oryza sativa), 50% wood and 50% bamboo; and 50% wood and 50% rice husk. Panels exposed to the decay the brown-rot fungus (Gloeophyllum trabeum, and the white-rot fungus (Trametes versicolor), and, in a choice feeding trial, to termites (Nasutitermes corniger). The rice husk particleboards had the highest resistance of all samples and the bamboo particleboards had the lowest resistance. T. versicolor fungi produced a larger mass loss in the particleboards than did G. trabeum. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The knowledge about lignocellulosic compounds strength to the attack of microorganisms is essential for preventing deterioration and also for knowing the correct usage of the material. Accordingly it was evaluated the natural resistance of wood panels made of particles of wood (Eucalyptus grandis) and/or bamboo (Bambusa vulgaris) to decay fungi. Particleboards were produced in laboratory, each of them with dimensions 50x50x0.95cm and density pre-set at 0.70g cm-3, in proportions of 100:0, 75:25, 50:50, 25:75 and 0:100 of wood and bamboo, respectively. The particles mass represented 91% of the dry mass of each panel while the remainder was formed by the urea-formaldehyde adhesive (8%) and paraffin (1%). The panels were tested in the laboratory and Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) were used to determine the natural resistance to attack by wood decay fungi. It was observed that panels which were made with a mixture of particles of wood and bamboo were less resistant to attack by decay fungi. Panels that were made from bamboo or wood only showed similar biological resistance. Among fungi, T. versicolor was the one that attacked panels more severely. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)