RESUMO: O objetivo deste trabalho foi extrair lignina de Eucalyptus sp. licor negro kraft e avaliar a influência de sua adição nas propriedades do adesivo lignina-fenol-formaldeído. Os adesivos foram sintetizados em diferentes porcentagens de massa de fenol por lignina, denominados adesivos lignina-fenol-formaldeído nas proporções de 25, 30, 50, 75 e 80%. Os parâmetros avaliados nos adesivos foram pH, teor de sólidos totais, teor de compostos orgânicos, teor de compostos inorgânicos, tempo de gelatinização e comportamento do adesivo na linha de cola. O pH variou de 10,63 a 11,65. Para o teor de sólidos totais foi encontrado o valor de 53 a 69%. Os teores de compostos orgânicos variaram de 51 a 75% e de inorgânicos de 25 a 49%. Observou-se que com a adição da macromolécula na formulação do adesivo, o teor de sólidos totais e orgânicos foi reduzido proporcionalmente enquanto o de sólidos inorgânicos foi elevado. O tempo de gelatinização foi reduzido devido à adição de lignina. As menores proporções de adição apresentaram melhor penetração e fluidez na interface com a madeira. A lignina kraft extraída do licor negro kraft de eucalipto é um ótimo adesivo com potencial para substituir parcialmente o fenol derivado do petróleo, com grande potencial para uso e aplicação nos setores aeronáutico e automotivo, no processo de colagem de peças estruturais. RESUMO sp ligninafenolformaldeído. ligninafenolformaldeído formaldeído. formaldeído 30 50 7 80 80% cola 1063 10 63 10,6 1165 11 65 11,65 5 69 69% 2 49 49% Observouse Observou se elevado madeira petróleo automotivo estruturais 3 8 106 1 6 10, 116 11,6 4 11,

ABSTRACT: The objective of this research was to extract lignin from Eucalyptus sp. kraft black liquor and to evaluate the influence of its addition on the properties of the lignin-phenol-formaldehyde adhesive. The adhesives were synthesized at different phenol mass percentages by lignin, called lignin-phenol-formaldehyde adhesives in the proportions of 25, 30, 50, 75 and 80%. The parameters evaluated in the adhesives were pH, total solid content, organic compound content, inorganic compound content, gelatinization time and adhesive behavior in the glue line. The pH ranged from 10.63 to 11.65. For the total solid content was found the value of 53 to 69 %. The contents of organic compounds ranged from 51 to 75% and inorganic from 25 to 49%. It was observed that with the addition of macromolecule in the adhesive formulation, the total and organic solid content was reduced proportionally while the inorganic solid was high. The gelatinization time was reduced due to the addition of lignin. The lower proportions of addition presented better penetration and fluidity in interface with the wood. The kraft lignin extracted from eucalyptus kraft black liquor is a great adhesive with potential to partially replace petroleum-derived phenol, with great potential for use and application in the aeronautical and automotive sectors, in the bonding process of structural parts. ABSTRACT sp ligninphenolformaldehyde formaldehyde 30 50 7 80 80% line 1063 10 63 10.6 1165 11 65 11.65 5 6 % 2 49 49% formulation high wood petroleumderived petroleum derived sectors parts 3 8 106 1 10. 116 11.6 4 11.

Resumo No Brasil, construções em madeira do tipo light woodframe possuem envelopamento estrutural do painel dependente do uso de chapas de OSB (Oriented Strand Board), o que implica em uma dificuldade em seu acesso por parte da população. Para ampliar a aplicação do sistema, uma possibilidade consiste em um projeto não atrelado aos monopólios de componentes construtivos. Uma possibilidade é a substituição da camada de envelopamento estrutural dos painéis por tábuas de madeira serrada convencional. Como objetivo esta pesquisa analisa a viabilidade de utilização e o comportamento de painéis de madeira serrada com envelopamento em tábuas de pinus quando solicitados a esforços horizontais, utilizando modelo numérico de simulações em software. O trabalho estuda cinco diferentes tipologias de painéis: um modelo digital de calibração baseado em experimento ensaiado em laboratório; quatro modelos de diferentes configurações, comparando entre si o desempenho estrutural de cada um com dados publicados na literatura. A modelagem digital utilizou dados experimentais já obtidos em trabalhos anteriores. Dos cinco tipos estudados quanto à tensão-deformação, apenas o Modelo 05 não se mostrou viável pela alta concentração de tensão observada nos conectores. Os demais modelos se mostraram adequados aos critérios preconizados por normas e documentos técnicos referenciados. Brasil Oriented Board, Board , Board) população sistema construtivos convencional horizontais software laboratório configurações literatura anteriores tensãodeformação, tensãodeformação deformação, deformação tensão-deformação 0 conectores referenciados

Abstract In Brazil, light woodframe buildings rely on the use of OSB (Oriented Strand Board), what implies a difficulty in its access by part of the population. To increase the applicability of the system one proposition consists in a woodframe project that is not bound by the monopoly over constructive components. A possible way consists in the substitution of the coating of the panels with standard Pinus boards. The objective of this research is therefore to analyze the viability and the behavior of wood panels with Pinus board coating when submitted to horizontal loads, utilizing as method digital simulations. This paper lists five different panel topologies, to calibrate it: one digital model of a previous lab experiment; four panels with different configurations, comparing them between themselves and with the literature in regards of structural performance. The utilized method was of the digital simulation with previous laboratory data calibration. Among the five types studied, only Model 05 exhibited high stress concentrations at connectors, rendering it unviable. The other models meet the criteria of referenced standards and technical documents. Brazil Oriented Board, Board , Board) population components boards loads simulations topologies experiment configurations performance calibration studied 0 connectors unviable documents

Abstract This study aimed to evaluate the effect of thermal treatment on the adhesion quality of bonded joints in high-density wood, specifically Corymbia citriodora and Eucalyptus pellita, using resorcinol formaldehyde and castor oil-based polyurethane adhesives. It was used at temperatures of 160 ºC, 180 ºC and 200 °C, being compared with a control batch. The percentage of failure in the wood was analyzed to evaluate the quality of the bonding. The castor oil-based polyurethane adhesive exhibited higher values of viscosity and solid content than resorcinol formaldehyde. Eucalyptus pellita showed higher shear strength values compared to Corymbia citriodora wood. The increase in temperature reduced the shear strength for both woods. The ratio between the strength of the bonded wood and solid wood, at the same treatment temperature, often exceeded one, indicating the formation of an adhesive-fiber composite, which enhances the strength of the bonded interface, especially for C. citriodora wood. Overall, there was better bonding of Eucalyptus pellita wood with resorcinol formaldehyde, and it exhibited less thermal degradation due to lower mass loss. highdensity high density oilbased oil based adhesives 16 18 20 C °C batch woods one adhesivefiber fiber composite interface Overall loss 1 2

Resumo Esse estudo teve como objetivo avaliar o efeito do tratamento térmico na qualidade da adesão de juntas coladas de madeira de alta densidade, Corymbia citriodora e Eucalyptus pellita utilizando os adesivos resorcinol e poliuretano vegetal à base de óleo de mamona. O tratamento térmico foi realizado nas temperaturas de 160 ºC, 180 ºC e 200 °C, sendo comparadas com um lote controle. A qualidade da colagem foi avaliada através do teste de cisalhamento e análise do percentual de falha na madeira. O adesivo de poliuretano de mamona apresentou maiores valores de viscosidade e teor de sólidos, do que o resorcinol formaldeído. O Eucalyptus pellitaexibiu maiores valores de resistência ao cisalhamento que a madeira de Corymbia citriodora. O aumento da temperatura reduziu a resistência ao cisalhamento para ambas as madeiras. A razão entre a resistência da madeira colada com madeira solida, na mesma temperatura de tratamento, muitas vezes atingiu valores superiores a um, indicando a formação de um compósito adesivo-fibras, que aumenta a resistência da interface colada, especialmente para madeira de C. citriodora. De forma geral, houve uma melhor colagem da madeira de Eucalyptus pellita, com resorcinol formaldeído, e está exibiu menor degradação térmica, devido à menor perda de massa. densidade 16 18 20 C °C controle sólidos formaldeído madeiras solida adesivofibras, adesivofibras fibras, fibras adesivo-fibras geral térmica massa 1 2

Abstract Understanding the geotechnical behavior of a municipal solid waste landfill (MSW) requires the filtering of several studies. Regarding the mechanical behavior, there are several discussions about the conditions for the stability maintenance of these structures. This stability depends a priori on the resistance of the compacted material to remain itself stable in a way that it does not generate ruptures or slips. Of various materials compacted found in the MSW landfills, high percentages of fibers (such as plastic, fabric and wood) are verified, these materials have a great influence on the mechanical behavior of the structure. These fibers in turn produce in general an increase in the geotechnical parameters: cohesion (c), friction angle (ϕ) and tensile (ζ), which consequently increase the degree of stability of the landfill. In this context, the present work performed evaluations of the effect of fiber tensile and shear strength in samples of Muribeca’s MSW landfills, the analyzes were performed by laboratory tests using a specimen of aged residues collected in the field, with a deposition age of 10 years. With the collected sample, direct shear tests were performed on 3 different sample proportions of fibers: 0%, 16.17% and 32.33%, in two conditions of test: flooded and non-flooded. From the results obtained in the tensile angles (ζ) in the condition of flooded of 10.2° and 5.0°, for the percentages of 16.17% and 32.33%, respectively. (MSW studies structures slips landfills such plastic wood verified structure parameters c, c , (c) ϕ (ϕ ζ, ζ context Muribecas Muribeca s field 1 years 0 0% 1617 16 17 16.17 3233 32 33 32.33% test nonflooded. nonflooded non flooded. non-flooded (ζ 102 2 10.2 50 5 5.0° respectively (c 161 16.1 323 32.33 10. 5.0 16. 32.3 5. 32.

ABSTRACT Background: Acacia mearnsii and Eucalyptus dunnii are species planted mainly for tannin and cellulose production. However, its woods have characteristics favorable to their use for energy generation, being commercialized in the form of firewood, chips or charcoal too. Biochar is a stable form of carbon that can be obtained by converting small particles of wood in the pyrolysis process and that can be used as solid fuel, among other applications as a soil conditioner. In this study, the properties of biochar produced in a horizontal reactor using wood of these species and under milder temperatures were evaluated. Results: Temperature of 350 oC and the reaction time of 30 minutes promoted an increase in higher calorific value of 33% for A. mearnsii and 51% for E. dunnii, with gravimetric yield of 39% and 32%, respectively. it was found that the 250 and 300 oC was not efficient to carbonize the wood of both species. An increase in specific surface area is observed with increasing carbonization temperature. Bigger increases were produced at temperatures of 350 oC for E. dunnii and 420 oC for A. mearnsii, with increase in porosity. At these temperatures, there was an increase in surface area and a decrease in pore size. Conclusion: In temperatures of 350 oC, the woods of both species provided a good quality biochar with porosity, surface area, pore size and pyrolysis yield suitable for energy use. For soil conditioning use, considering these aspects, suggested to test the appropriate temperatures for each species, between 350 and 420 oC. Background production However generation firewood too fuel conditioner study evaluated Results 35 3 33 A 51 E 39 32 32% respectively 25 temperature 42 porosity Conclusion aspects 5 2 4

Abstract The impact of forestry practices was evaluated on Eucalyptus’s growth variables and mortality dynamics. An experiment was conducted in Uruguay over sixteen years, sixteen spacing and thinning treatments were compared depending on the genetic material and productive objective. Tree height and diameter at breast height were assessed annually. All variables were analyzed using linear mixed models. Kaplan-Meier survival analysis and the Log Rank test were used to compare tree survival. 460 trees ha-1 from seed material resulted in the highest individual basal area (0.023 m2), while treatments with 2000 trees ha-1, without thinning, generated a greater yield per hectare (1014 m3 ha-1). Variations in mortality were detected in higher-density treatments (above 800 trees ha-1). This study underscores the critical importance of managing spacing, genetic material, and thinning practices to optimize Eucalyptus growth. Eucalyptuss s dynamics years objective annually models KaplanMeier Kaplan Meier 46 ha1 ha 1 ha- 0.023 0023 0 023 (0.02 m2, m2 m , m2) 200 ha1, 1, 1014 (101 ha1. . ha-1) higherdensity higher density above 80 4 0.02 002 02 (0.0 20 101 (10 8 0.0 00 (0. 2 10 (1 0. (0 (

Resumen: La ceniza de madera es un residuo del proceso de quema de ladrillos artesanales que se produce en las zonas más pobres del Perú. Constituye un gran problema debido a que no existe una gestión de esta clase de residuos sólidos y contamina grandes sectores de la población. En ese sentido, surge la importancia de emplear elementos naturales sostenibles como las cenizas de madera que puedan aportar en el rendimiento del concreto. Es por ello que, esta investigación tuvo por objetivo evaluar la influencia de la incorporación de ceniza de madera en las propiedades mecánicas del concreto, con incorporaciones de 8%, 12% y 16%, en función al peso del cemento, para lo cual se prepararon especímenes cilíndricos y viguetas. Los resultados respecto al asentamiento y peso unitario se redujeron considerablemente por debajo de sus muestras patrones, a diferencia de la temperatura que tuvo aumentos que oscilaron entre los 3°C. Por otro lado, la mezcla combinada de 8% de ceniza de madera resultó ser la mayor resistencia a la compresión, llegando a 308,73 kg/cm2 la cual representa un incremento del 9,04% con respecto a la muestra patrón, en tanto, la resistencia a la flexión fue 45,32 kg/cm2 representando un incremento del 5,96% respecto a la muestra patrón. Se concluye que la adición de ceniza de madera mejora significativamente las propiedades mecánicas del concreto con una dosis óptima de 8%, el resultado contribuye a que sea técnicamente viable como adición en la elaboración de concreto sustentable en la construcción civil.

Abstract: Wood ash is a residue from the artisanal brick burning process that is produced in the poorest areas of Peru. It is a major problem because there is no management of this type of solid waste and it contaminates large sectors of the population. In this sense, it is important to use sustainable natural elements such as wood ashes that can contribute to the performance of concrete. For this reason, the objective of this research was to evaluate the influence of the incorporation of wood ash on the mechanical properties of concrete, with incorporations of 8%, 12% and 16%, as a function of the weight of cement, for which cylindrical specimens and beams were prepared. The results with respect to slump and unit weight were considerably reduced below their standard samples, unlike the temperature, which had increases that ranged between 3°C. On the other hand, the combined mixture of 8% wood ash resulted in the highest compressive strength, reaching 308,73 kg/cm2 which represents an increase of 9,04% with respect to the standard sample, while the flexural strength was 45,32 kg/cm2 representing an increase of 5,96% with reference to the standard sample. It is concluded that the addition of wood ash significantly improves the mechanical properties of concrete with an optimum dosage of 8%, the result contributes to make it technically feasible as an addition in the elaboration of sustainable concrete in civil construction.

Abstract Knowing consumers' perceptions and purchase intentions is essential to satisfy their needs or exceed their expectations for products demand. At the national level, studies of this type focused on wood are scarce; therefore, this study analyzed the perception of the performance and purchase intentions of consumers to understand the decision processes in the consumption of wood products using different characteristics and comparing them with substitute products. In a first phase, the purchase intention of intermediate (n=197) and final (n=298) consumers of sawn wood products and furniture in the Greater Metropolitan Area of Costa Rica was analyzed through different advertisements. For this, advertisements were designed, and evaluations were made on attitudes and purchase intention considering the type of product, its origin, and whether they are certified or not. In a second phase, a choice experiment was developed to evaluate, by final consumers, specific attributes of wood products. The results showed that in general terms there is a favorable purchase intention for wood- based products; regardless of whether they are domestic or imported. The results of the choice experiment indicated that consumers prefer a product built with solid wood compared to processed wood (plywood), high durability, that does not require assembly, with a natural finish that naturally highlights the grain and imperfections of wood, and as expected, willing to pay the lowest possible price. It becomes evident that there is a preference of wood products particularly solid wood and a tendency to prefer those of domestic origin.

Resumen Conocer las percepciones e intenciones de compra de los consumidores es fundamental para satisfacer sus necesidades o superar sus expectativas en la demanda de productos. A nivel nacional los estudios de este tipo enfocados en madera son escasos; por tanto, se tuvo por objetivo analizar la percepción sobre el desempeño e intenciones de compra de personas consumidoras para entender los procesos de decisión en el consumo de productos maderables utilizando diferentes características y comparándolos con productos sustitutos. En una primera fase se analizó por medio de diferentes anuncios publicitarios la percepción sobre el desempeño y la intención de compra en los consumidores intermedios (n=197) y finales (n=298) de productos de madera aserrada y muebles en el Gran Área Metropolitana de Costa Rica. Para esto, se diseñaron anuncios publicitarios y se corrieron las evaluaciones sobre actitudes e intención de compra considerando el tipo de producto, su origen y si son certificados o no. En la segunda fase se desarrolló un experimento de escogencia (choice experiment) para evaluar, por personas consumidoras finales, atributos específicos de productos de madera. Los resultados evidencian que en términos generales hay una intención favorable de compra por productos a base de madera; incluso sin importar si son de origen nacional o importados. Los resultados del experimento de escogencia indican que las personas consumidoras prefieren un producto construido con madera sólida en comparación con madera procesada (madera contrachapada), de alta durabilidad, que no requiera ser ensamblado, con un acabado natural que resalta naturalmente la veta y las imperfecciones de la madera, y como era de esperar, dispuesto a pagar el menor precio posible. Se hace evidente que existe preferencia de productos de madera particularmente madera sólida y una tendencia a preferir aquellos de origen local.

RESUMO A compactação do solo é um problema recorrente na agricultura, levando à redução da produtividade das culturas. Diante disso, a aplicação de resíduo agroindustrial da queima de biomassa vegetal pode melhorar as propriedades químicas e físicas do solo. O objetivo deste trabalho foi avaliar o crescimento do capim paiaguás sob diferentes densidades do solo e doses de cinzas vegetal. O experimento foi conduzido em blocos casualizados, em esquema fatorial 5 × 5, composto por cinco valores de compactação do solo (1,0, 1,2, 1,4, 1,6 e 1,8 Mg m-3) e cinco doses de cinza vegetal (0, 8, 16, 24, 32 g dm-3), com quatro repetições. Densidades do solo acima de 1,2 Mg m-3 reduzem a massa seca do capim paiaguás. A dose de cinza de madeira de 20,42 g dm-3 apresenta o maior valor de massa seca da parte aérea. O crescimento da raiz é maior na dose de cinza de madeira de 16,52 g dm-3.

ABSTRACT Soil compaction is a recurring problem in agriculture that ultimately leads to a reduction in crop productivity. However, the application of agro-industrial residues from the burning of plant biomass can improve the chemical and physical properties of soil. The objective of this study was to evaluate the growth of Paiaguás grass under different soil densities and wood ash doses. The experiment was carried out in a randomized block design, under a 5 × 5 factorial scheme, with five soil compaction values (1.0, 1.2, 1.4, 1.6, and 1.8 Mg m-3) and five doses of wood ash (0, 8, 16, 24, and 32 g dm-3), with four replicates. A soil density greater than 1.2 Mg m-3 reduced the dry mass of Paiaguás grass. The wood ash dose of 20.42 g dm-3 led to the highest shoot dry mass. Root growth was highest at a wood ash dose of 16.52 g dm-3.

Abstract A novel lecture experiment is arranged, that could be used as a demonstration of burning wood with chemical identification of the main products of the oxidation. Pieces of standard Chinese chopsticks were burned in pure oxygen. Ways of proving the obtained products are offered. The solid product shows strongly alkaline reaction (pH > 11). For a maximum effect it is advisable to use a flow chamber (Petruševski and Najdoski, 2005). This experiment can be applied to teach processes of oxidation (burning), acids, bases and/or indicators. The experiment is suitable for classroom setting, providing an opportunity for active involvement of students in examining the properties of the resulting products.

Resumen Se organiza un novedoso experimento de lectura, que podría utilizarse como demostración de la quema de madera con identificación química de los principales productos de la oxidación. En realidad, se quemaron pedazos de palillos chinos estándar en oxígeno puro. Se ofrecen formas de probar los productos obtenidos. El producto sólido muestra una reacción fuertemente alcalina (pH > 11). Para un efecto máximo, se recomienda utilizar una cámara de flujo (Petruševski y Najdoski, 2005). Este experimento se puede aplicar para enseñar procesos de oxidación (combustión), ácidos, bases y/o indicadores. El experimento es adecuado para el salón de clases, brindando una oportunidad para que los estudiantes participen activamente en el examen de las propiedades de los productos resultantes.

ABSTRACT Glulam is a viable alternative for the rational use of wood, allowing the use of young timber. Also, when engineering the timber, it is possible to use lower quality trunks with a smaller diameter. However, the performance of the product depends on the species used, the thickness and position of the lamellae, the type of adhesive, the bonding performance. This work aimed to study the feasibility of using a fast growing timber for the production of glulam. The selected timber species was Eucalyptus urophylla, clonal COP 1404, which is characterized by its fast growth and lack of studies regarding its application in civil construction. A two-component polyurethane adhesive based on castor oil was used. The experimental program focused on the characterization of fresh timber and the mechanical performance of glulam compared to solid wood, using statistical methods to analyze the resistance of the prototypes. The results indicated that the adhesive was efficient in gluing the timber, so that shearing occurred in the timber, in addition to the flexural verification showing behavior of a single body, with no points of discontinuity due to the glue line. wood Also diameter However used lamellae urophylla 1404 construction twocomponent two component prototypes body line 140 14 1

RESUMO A Madeira Lamelada Colada (MLC) é uma alternativa viável para o aproveitamento racional da madeira, possibilitando o uso de madeiras jovens. Ainda, ao engenheirar a madeira, pode-se viabilizar o uso de troncos de menor qualidade e menor diâmetro. Entretanto, o desempenho do produto depende da espécie utilizada, das espessuras e posições das lamelas, do tipo de adesivo, do desempenho da colagem. Este trabalho teve como objetivo estudar a viabilidade do uso de uma madeira de rápido crescimento para a produção de MLC. A espécie de madeira selecionada foi Eucalyptus urophylla, clonal COP 1404, que se caracteriza por ter rápido crescimento e por ter uma lacuna em estudos que visam sua aplicação na construção civil. Empregou-se o adesivo poliuretano bicomponente à base de óleo mamona. O programa experimental teve como foco a caracterização da madeira in natura e o desempenho mecânico da MLC comparada à madeira maciça, empregando métodos estatísticos para a análise de resistência dos protótipos. Os resultados indicaram que o adesivo foi eficiente na colagem da madeira, de modo que o cisalhamento ocorreu na madeira, além da verificação à flexão ter mostrado comportamento de um corpo único, não tendo pontos de descontinuidade por conta da linha de cola. (MLC jovens Ainda podese pode diâmetro Entretanto utilizada lamelas urophylla 1404 civil Empregouse Empregou mamona maciça protótipos único cola 140 14 1

Abstract: The main objective of this study is to determine optimum cutting parameters in order to specify the effect of densification by compressing on the processing properties of solid wood material and to achieve the best surface quality in materials densified at different rates. In line with this goal, the widely grown and low-density black poplar (Populus nigra) tree species were selected as the experimental material. Samples, which were compressed and densified by Thermo-Mechanical method at 0 %, 20 % and 40 % ratios, were processed at 1000 mm/min, 1500 mm/min and 2000 mm/min feed speeds and in 12000 rpm, 15000 rpm, 18000 rpm rotation speed on a computer numerical control machine by using two different cutters. Surface roughness values (Ra and Rz) were measured in order to evaluate surfaces obtained. Smoother surfaces were obtained in computer numerical control machining of densified samples. The lowest surface roughness values occurred in 40 % densified samples, which were the densest. The lowest surface roughness was obtained when 40 % densified samples were processed with cutter no.1 (two-flutes straight end mill), at 1000 mm/min feed speed and at 18000 rpm. Ra and Rz roughness values increased with the increase of the feed rate.

Alkali-activated binders (AAB) are inorganic materials produced by a mixture between a solid precursor and an alkaline activator, wherein, the reaction results in a material with properties similar to Portland cement hydration. The advantages of AAB over Portland cement are the possibility of using alternative materials, demanding low energy and low CO2 emission. The primary objective of this study was to produce an alkali-activated binder (AAB) using calcined wood waste ash (CWWA) as a solid precursor due to its beneficial properties. CWWA was obtained by burning wood wastes in a furnace, then calcined in a laboratory oven at 600 °C to remove unburned particles. Afterward, the ash was milled and then physiochemically characterized by chemical composition, X-ray diffraction (XRD), particle size distribution, and scanning electron microscopy (SEM). The milled CWWA was employed in AAB mortars and pastes activated with sodium hydroxide (NaOH) to assess the influence of alkaline activator concentration. In this work, the Na+ concentrations varied in the 6.5-12.5 mol.kg-1 range. Mortars were assessed by compressive strength, whereas pastes were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS) for samples cured after 7 days at 60 °C. Results showed that the CWWA is mainly composed of SiO2 (67.9 wt%) and the presence of an amorphous phase and quartz as the main crystalline phase (XRD). The compressive strength of mortars showed that the CWWA activated with a Na+ concentration of 6.5 ml.kg-1 achieved the highest compressive strength (23.2 ± 1 MPa). Microstructural studies of pastes showed the formation of sodium carbonate (XRD) and reaction products (FTIR) in a dense microstructure (SEM/EDS). Hence, the key findings suggest that employing CWWA as a solid precursor offers a viable choice for producing a more sustainable AAB. Alkaliactivated Alkali (AAB wherein hydration CO emission alkaliactivated alkali (CWWA furnace C particles Afterward composition Xray X ray XRD, XRD , distribution SEM. SEM . (SEM) NaOH (NaOH work Na 6.512.5 65125 12.5 6 5 12 6.5-12. mol.kg1 molkg1 molkg mol.kg mol kg mol.kg- range FTIR, FTIR microscopy/energydispersive microscopyenergydispersive microscopy/energy dispersive SEM/EDS SEMEDS EDS (SEM/EDS SiO 67.9 679 67 9 (67. wt% wt XRD. 65 6. ml.kg1 mlkg1 mlkg ml.kg ml ml.kg- 23.2 232 23 2 (23. MPa. MPa MPa) (XRD (FTIR SEM/EDS. Hence (SEM 512 6.512. 6512 125 12. 6.5-12 kg1 energydispersive microscopyenergy 67. (67 23. (23 51 6.512 651 6.5-1 (6 (2 6.51 6.5- (

ABSTRACT Background: Determining the basic density of the wood is usually defined as a simple process, but it requires caution and the operator’s skill to avoid errors in the analysis. In addition, it involves sample preparation and time to saturate the wood until obtaining the dry sample mass. The development of alternative measurement techniques could reduce the time to obtain the results and provide reliable values. Therefore, this study aimed to develop multivariate models to estimate the basic density of native woods using near-infrared spectra (NIR). Basic densities were determined by the water immersion method, and the values were associated with NIR signatures. Spectra were directly collected on the wood transversal and radial faces with an integrating sphere. Partial least squares regression (PLS-R) was calibrated and validated to estimate basic density based on spectral signatures. Results: In the cross-validation and prediction of the models, the results were promising. The coefficients of determination varied from 0.87 to 0.93 with a standard error of 0.01 %. The partial least squares discriminant analysis (PLS-DA) efficiently classified the wood species. The ratio of performance to deviation obtained satisfactory values, a minimum of 2.81 and a maximum of 4.20. Conclusion: The statistical parameters of the models based on NIR spectra showed potential for density measurements in floors, furniture, and solid wood products. Background process operators operator s addition mass Therefore nearinfrared near infrared NIR. . (NIR) method signatures sphere PLSR PLS R (PLS-R Results crossvalidation cross validation promising 087 0 87 0.8 093 93 0.9 001 01 0.0 % PLSDA DA (PLS-DA species 281 2 81 2.8 420 4 20 4.20 Conclusion floors furniture products (NIR 08 8 0. 09 9 00 28 2. 42 4.2 4.

The negative health and socio-economic impacts of emissions associated with domestic fuel burning are widely recognized. Although there has been much progress in the provision of electricity to households in South Africa, many still rely on solid fuel sources such as wood and coal. While various investigations have been done on reducing household emissions by reducing the use of polluting fuels and improvements in combustion efficiency, comparatively fewer studies have been conducted on the reduction of emissions through use of abatement technology. Catalytic oxidation could be utilized to oxidize particulate matter precursors such as volatile organic compounds and soot particles to reduce secondary particulate formation. Although catalytic methods have not been effectively utilized in practical domestic applications, studies have shown effective soot reduction during laboratory testing. This study investigated the synthesis and use of a manganese oxide based catalyst to reduce particulate matter from domestic fuel burning stoves. The catalyst was synthesized onto a mesh substrate and inserted into the flue of the stove. During field testing, the presence of the catalyst increased the mass of particulate matter collected onto PTFE filters used for gravimetric analysis, with Scanning Electron Microscopy (SEM) analysis showing spherical particles in the pores of the filters used during the catalytic runs. The baseline runs had very few of these particle clusters. Energy Dispersive X-Ray (EDX) analysis of the catalyst run filters did not detect manganese, revealing that increased particulate concentrations were not as a result of macroscopic particles of the catalyst being dislodged from the support. Dislodgement of very small metal particles from the catalyst could, however serve as nucleation nodes for particle growth which would have a non-metal coating leading to the non-detection of manganese. The increase in particulate matter could also be caused by the impingement of particulate matter precursors on the catalyst followed by particle growth and dislodgement into the flue gas. The testwork showed that an active catalyst can be synthesized onto a mesh catalyst support in a relatively simple and cost-effective manner, which can be utilized in domestic fuel burning devices. It is recommended that a range of optimized, potentially active catalysts be tested to improve the oxidation of particulate matter precursors to carbon dioxide.