In the context of the circular bioeconomy and cleaner production, the incorporation of the by-products of plant biomass production in the bioenergy chain is fundamental. However, lignocellulosic ...wastes have properties that hinder their use for the production of biofuels. This study aims to evaluate how blends of lignocellulosic wastes improve the physical, chemical, and mechanical quality of pellets destined to the industrial sector, and to identify the challenges associated with the use of agroforestry biomass as raw material for pelletizing. Pellets were produced from blends of soybean wastes, sorghum wastes, pine needles, rice powder,
Eucalyptus
sawdust, and charcoal fines. Additionally, pure pellets composed of soybean wastes, sugarcane bagasse, and pine wood were evaluated. The effect of biomass type on the energy density, ash content, net heating value, and ultimate analysis was significant. The pellets produced with soybean wastes presented high contents of N (3.5–4.9%) and ashes (16.4–26.7%), besides low mechanical durability (≤ 96%), hindering its commercialization for industrial purposes. Pellets with sugarcane bagasse presented N (1.5%), S (0.03%), ashes (5.6%), mechanical durability (96.6%), and net heating value (15.1 MJ kg
−1
), suitable for industrial energy use in accordance with ISO 17225-6. The high N and ash contents and the low mechanical durability are the greatest challenges for the energy use of pellets produced from Brazilian agroforestry wastes.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract The hybrid material was obtained from the synthesis of graphene oxide (GO) followed by GO chemical reduction with L‐ascorbic acid. Then hydrothermal synthesis was carried out to form and ...grow carbon dots (CDs) on the surface of reduced graphene oxide (rGO). The material obtained, CD@rGO, was characterized by transmission electron microscopy (TEM), the infrared (FTIR), Raman and UV‐visible (UV‐Vis) spectroscopy, in addition to X‐ray diffractometry (XRD), spectroscopy and electrochemical methods. The results indicated the formation of carbon dots on the surface of rGO. The study of the voltammetric determination of hydroxychloroquine (HCQ) was performed using adsorptive stripping voltammetry (AdSV) and employing a modified electrode with CD@rGO (ECR). Optimizations were kept in the electrolytic environment and AdSV technique parameters, making it possible to obtain a LOD and LOQ of 2.40 and 7.99 pmol L −1 , respectively. The evaluation of the ECR electrochemical stability, repeatability and reproducibility tests were performed with maximum variations of up to 2.79 and 2.03 %, respectively. Determinations in commercial samples of HCQ (tablets) and synthetic urine, recovery in the range of 101.55–106.83 % were obtained.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The influence of the lignin macromolecule composition, extractives, volatile matter (VM), and fixed carbon (FC) contents on the reactivity and easiness of wood combustion is not fully understood, ...especially concerning species from fast-growing plantations. This study aims to close this scientific gap revealing the wood chemical composition effects on the combustibility of Eucalyptus clones. Moreover, we proposed new quantitative indexes that allow suitable grouping of genetic materials for energy purposes. The lignin, acetone-soluble extractives, VM, FC, and ash contents, as well as the ratio syringyl (S)/guaiacyl (G), were determined. The thermogravimetric analyses provided the combustion parameters. The characteristics that most contributed to the grouping of Eucalyptus clones were energy productivity (GJ ha−1 and GJ tree−1), energy density (GJ m−3), acetone-soluble extractives (% based on dry mass - db), VM (% db), and the maximum rate of combustion (% min−1). Clones with G units ≤20 g kg−1 db, acetone-soluble extractives ≤1.0% db, and FC ≤ 16% db had easier ignition and better reactivity during the burning. Clones with VM/FC ratio ≥5.0 showed maximum combustion rate ≥8.0% min−1 and acetone-soluble extractives ≤1.1% db. The findings of this investigation are useful to managers’ decision-making and contribute to the selection and rational use of the wood for energy purposes.
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•The acetone-soluble extractives reduced the wood reactivity during the combustion.•Lignins with a higher proportion of guaiacyl units decrease the fuel reactivity.•Slight changes in proximate composition can influence the Eucalyptus combustibility.•The higher volatile matter content is correlated with the better fuel reactivity.•Woods with extractives content ≤1.0% and FC ≤ 16% presented easier ignition.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
RESUMO: Objetivo: Realizar a adaptação transcultural e a validação, no contexto cultural brasileiro, do instrumento de impacto da obesidade Patient-Reported Outcomes in Obesity (PROS). Métodos: O ...processo de adaptação transcultural contou com a tradução do idioma original, inglês, para o português, executada por dois tradutores qualificados e independentes. A retrotradução foi realizada por dois professores de inglês, nativos, sem qualquer conhecimento médico nem da escala original. Um comitê de especialistas foi composto de pesquisadores para avaliar as equivalências semântica, idiomática, experiencial e conceitual. O pré-teste da versão brasileira, denominada PROS-Br, foi realizado com dez indivíduos adultos com obesidade. Para a avaliação das propriedades psicométricas, foi realizado um estudo epidemiológico de delineamento transversal. A população foi composta de 120 indivíduos adultos com obesidade, brasileiros, presentes para consulta médica em ambulatório-escola. Para análises psicométricas, foram utilizadas a Teoria de Resposta ao Item e análise fatorial com extração de componentes principais. Para aferição da confiabilidade foi utilizado o indicador α-Cronbach. Resultados: Na análise de confiabilidade, o PROS-Br apresentou α-Cronbach de 0,82. Dois fatores explicaram 58,3% da variância total na análise de componentes principais, envolvendo aspectos comportamentais e físicos. As curvas da Teoria de Resposta ao Item mostraram que todas as perguntas apresentam características discriminatórias, apontando para a adequação da versão brasileira proposta. Conclusão: A versão brasileira mostrou-se válida e confiável para aferir a qualidade de vida de indivíduos com obesidade, possibilitando desenvolver estratégias de intervenção, planejamento e execução de ações nos serviços e na política pública de saúde.
ABSTRACT: Objective: To perform a cross-cultural adaptation and validation in the Brazilian cultural context of questionnaire Patient-Reported Outcomes in Obesity (PROS). Methods: The cross-cultural adaptation process involved the translation from original English language into Brazilian Portuguese by two qualified and independent translators. The back-translation was performed by two English language teachers who were native speakers, without any medical knowledge of the original scale. An expert committee was created with researchers to assess semantic, idiomatic, experiential and conceptual equivalence. The pre-test of the Brazilian version, named PROS-Br, was carried out with ten adults with obesity. To assess the psychometric properties of the instrument, a cross-sectional epidemiological study was carried out. The population consisted of 120 Brazilian adults with obesity who went to the appointment at a school-clinic. The Item Response Theory and Factor Analysis with Principal Component Extraction was used for the psychometrics analysis. To measure reliability, the α-Cronbach indicator was used. Results: In the reliability analysis, α-Cronbach was 0.82. Two factors explained 58.3% of the total variance in the principal component analysis, involving behavioral and physical aspects. Item Response Theory curves showed that all questions have discriminatory characteristics, pointing to the adequacy of the proposed version. Conclusion: The Brazilian version was proven valid and reliable to measure the quality of life of individuals with obesity, allowing one to develop intervention strategies, plan and execute actions at services and for public health policies.
ABSTRACT The study of the flow properties and particle surfaces of a food powder is essential for predicting its behaviour during processing and commercialization. The objective of this work was to ...determine the powder flow properties of lyophilized green coconut pulp with different concentrations of maltodextrin. Samples containing 0, 5, 10 and 15% (m/m) maltodextrin were lyophilized, and the flow index (FI), wall friction angles and densities were determined. The microstructure of the powders was evaluated by scanning electron microscopy (SEM). The samples containing 0 and 5% maltodextrin showed 1.87 FI, classifying them as very cohesive powders, and those containing 10 and 15% cohesive powder showed 2.12 and 2.43 FI, respectively. The powder densities varied from 138.6 to 287.6 kg/m3, and the wall friction angle varied from 15.8 to 39.8°. The powder particles presented irregular shapes and rough surfaces, especially in powders containing 0, 5 and 10% maltodextrin. The powder containing 15% had smoother and less agglomerated surfaces. An increase in the amount of maltodextrin added to the pulp made the particles smoother and denser and improved the fluidity of the powder.
RESUMO O estudo das propriedades de escoamento e da superfície das partículas de um alimento em pó é essencial para prever seu comportamento durante o processamento e comercialização. O objetivo deste trabalho foi determinar as propriedades de escoamento do pó da polpa de coco verde liofilizada com diferentes concentrações de maltodextrina. Amostras contendo 0, 5, 10 e 15% (m/m) de maltodextrina foram liofilizadas e o índice de fluxo, ângulos de atrito com parede e densidades foram determinados. A microestrutura dos pós foi avaliada por microscopia eletrônica de varredura (MEV). As amostras contendo 0 e 5% de maltodxtrina apresentaram FI de 1,87 sendo classificadas como pós muito coesos e as amostras com 10 e 15% como coesos, com FI de 2,12 e 2,43, respectivamente. As densidades dos pós variaram de 138,6 a 287,6 kg / m3 e o ângulo de atrito da parede entre 15,8 e 39,8º. As partículas dos pós apresentaram formas irregulares e superfícies rugosas, principalmente em pós contendo 0, 5 e 10% de maltodextrina. O pó contendo 15% apresentou superfícies mais lisas e menos aglomeradas. O aumento da maltodextrina adicionada à polpa tornou as partículas mais lisas, mais densas e melhorou a fluidez do pó.
At a moment when the importance of planted forests in the Amazon region is increasing, hypsometric models become highly relevant tools as they allow monitoring of and planning for tree plantations in ...a way that is practical and economic for the producer. Thus, the objective of the current study was to select and adjust a model of hypsometric relationships for a clonal plantation of Tectona grandis Linn F., submitted to selective
thinning, located in Capitão Poço municipality, Pará state, Brazil. Data were collected from permanent plots in five-year-old stands using the fixed area method and systematic process. The best adjusted model was selected with an adjusted determination coefficient (R²aj.%), residual standard deviation of the percentage estimate (Syx%), recalculated residual standard error (Syxr%), diagnosis of distribution of residuals as a percentage and
the Percent Average Deviation (PAD%). Hyperbolic models 2 and 3 had the highest determination coefficients (83.42 and 83.40%) and lowest PAD (-0.006 and -0.154%). The polynomial (1) and hyperbolic models (2 and 3) showed the smallest errors in related to the estimates. Model 2 (hyperbolic) was found to generate the
best estimate of total T. grandis clonal plantation height. Use of this hypsometric model will allow a significant
reduction of costs and time in forest inventory studies.
Charcoal productivity in brick kilns is controlled by factors such as, the pyrolysis process and kind of raw material, which impose a challenge for the selection of the best clones. This study ...investigates the tree growth characteristics as a parameter for the improvement of selection and classification of Eucalyptus clones, with the quality and availability required by the steel industry, in addition to the properties of wood and charcoal. Parameters as the diameter at breast height (DBH), total height, and wood basic density (WBD) of fourteen clones were measured. Wood specimens were converted to charcoal in laboratory conditions and the carbonization yields, charcoal properties, and the volume of wood required to produce 1 t of charcoal (specific consumption) were evaluated. Eucalyptus clones with DBH ≥15.1 cm, WBD ≥560 kg/m3, and gravimetric yield ≥35% provided low specific consumption (<5.1 m³/t), increased brick kilns productivity, and resulted in denser charcoals (380 kg/m3). Clones with WBD ≤500 kg/m3 are not recommended for steel charcoal production. The E. urophylla x E. camaldulensis hybrid (clone 1004), E. urophylla (clone 1009), and E. grandis hybrid (clone 1039) highlighted due to the productivity, bioreducer quality, and specific consumption (<5.2 m³/t).
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•Eucalyptus with wood density ≤500 kg/m3 is not recommended for energy purposes.•The diameter at breast height is criterion for classification of Eucalyptus clones.•Wood density is a key criterion for selecting charcoal for steel production.•Wood density, tree growth, and pyrolysis yields indicates best clones.•The carbonization of wood with WBD ≥560 kg/m3 results in denser charcoals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Makoni e Pennycook (2007) advogam por (des)invenções no âmbito do ensino de línguas e demais componentes dos estudos da linguagem. Nessa esteira, fundamentamos na ideia de que as invenções são ...construções sociais e que apenas se consolidam por meio de crenças e verdades (com)partilhadas. Assim, traçamos, neste artigo, uma discussão sobre como certas invenções, especificamente aquelas ligadas à colonização linguística e cultural, ainda reverberam por meio de colonialidades que condicionam nosso modo de agir e conceber o mundo e nós mesmos/as. De modo particular, elegemos a interculturalidade como uma invenção recorrente no campo da educação linguística e buscamos propiciar o exercício da suspeita (MONTE MÓR, 2017) acerca de como a noção de interculturalidade tem sido inventada nesse campo e quais poderiam ser vias alternativas de sua (des)invenção. Nesse exercício, notamos indícios de um viés de interculturalidade funcional (WALSH, 2009) em dois documentos oficiais que têm orientado ações no campo em foco. No entanto, as discussões tecidas nos fazem entender que, sem uma perspectiva crítica, o ensino intercultural de línguas apenas dará prosseguimento aos interesses modernos/coloniais. Nesse sentido, apostamos na interculturalidade crítica como alternativa de (des)invenção no campo de educação linguística, advinda de bases epistemológicas suleadas.
To perform a cross-cultural adaptation and validation in the Brazilian cultural context of questionnaire Patient-Reported Outcomes in Obesity (PROS).
The cross-cultural adaptation process involved ...the translation from original English language into Brazilian Portuguese by two qualified and independent translators. The back-translation was performed by two English language teachers who were native speakers, without any medical knowledge of the original scale. An expert committee was created with researchers to assess semantic, idiomatic, experiential and conceptual equivalence. The pre-test of the Brazilian version, named PROS-Br, was carried out with ten adults with obesity. To assess the psychometric properties of the instrument, a cross-sectional epidemiological study was carried out. The population consisted of 120 Brazilian adults with obesity who went to the appointment at a school-clinic. The Item Response Theory and Factor Analysis with Principal Component Extraction was used for the psychometrics analysis. To measure reliability, the α-Cronbach indicator was used.
In the reliability analysis, α-Cronbach was 0.82. Two factors explained 58.3% of the total variance in the principal component analysis, involving behavioral and physical aspects. Item Response Theory curves showed that all questions have discriminatory characteristics, pointing to the adequacy of the proposed version.
The Brazilian version was proven valid and reliable to measure the quality of life of individuals with obesity, allowing one to develop intervention strategies, plan and execute actions at services and for public health policies.
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