Publisher: SciELO   (Total: 893 journals)

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Showing 201 - 400 of 893 Journals sorted alphabetically
Cubo. A Mathematical J.     Open Access  
Cuestiones Constitucionales     Open Access   (Followers: 2, SJR: 0.1, CiteScore: 0)
Cuicuilco     Open Access   (Followers: 1)
Cuicuilco. Revista de Ciencias Antropológicas     Open Access   (Followers: 2)
Cultivos Tropicales     Open Access   (Followers: 1)
Cultura y Representaciones Sociales     Open Access   (Followers: 2)
Culturales     Open Access   (Followers: 3)
Dados - Revista de Ciências Sociais     Open Access   (SJR: 0.37, CiteScore: 0)
De Jure     Open Access   (Followers: 1)
DELTA : Documentação de Estudos em Lingüística Teórica e Aplicada     Open Access   (SJR: 0.133, CiteScore: 0)
Dementia & Neuropsychologia     Open Access   (Followers: 10, SJR: 0.205, CiteScore: 0)
Dental Press J. of Orthodontics     Open Access   (Followers: 5, SJR: 0.489, CiteScore: 1)
Desacatos     Open Access   (Followers: 1)
Desacatos : Revista de Antropología Social     Open Access   (Followers: 2)
Desarrollo y Sociedad     Open Access   (Followers: 3, SJR: 0.109, CiteScore: 0)
Diálogo Andino - Revista de Historia, Geografía y Cultura Andina     Open Access   (Followers: 1, SJR: 0.116, CiteScore: 0)
Diánoia     Open Access   (Followers: 1)
Dimensión Empresarial     Open Access  
Discusiones Filosóficas     Open Access   (Followers: 2)
Dynamis : Acta Hispanica ad Medicinae Scientiarumque Historiam Illustrandam     Open Access   (Followers: 3, SJR: 0.131, CiteScore: 0)
e-J. of Portuguese History     Open Access   (Followers: 2, SJR: 0.101, CiteScore: 0)
e-Pública : Revista Eletrónica de Direito Público     Open Access   (Followers: 2)
Earth Sciences Research J.     Open Access   (Followers: 2)
Eclética Química     Open Access   (Followers: 1)
Ecología en Bolivia     Open Access  
Economia Aplicada     Open Access   (SJR: 0.208, CiteScore: 0)
Economia e Sociedade     Open Access  
EconoQuantum     Open Access  
Educação & Sociedade     Open Access   (Followers: 3)
Educação e Pesquisa     Open Access   (Followers: 1, SJR: 0.163, CiteScore: 0)
Educação em Revista     Open Access  
Educación Matemática     Open Access  
Educación Médica     Open Access   (Followers: 1, SJR: 0.236, CiteScore: 0)
Educación Médica Superior     Open Access   (Followers: 1, SJR: 0.237, CiteScore: 0)
Educación y Educadores     Open Access  
Educar em Revista     Open Access  
EDUMECENTRO     Open Access  
Eidos     Open Access   (SJR: 0.119, CiteScore: 0)
En-Claves del pensamiento     Open Access   (Followers: 1, SJR: 0.194, CiteScore: 0)
Encuentros     Open Access  
Ene : Revista de Enfermería     Open Access  
Enfermería Global     Open Access   (Followers: 3, SJR: 0.165, CiteScore: 0)
Enfermería Nefrológica     Open Access   (Followers: 1, SJR: 0.198, CiteScore: 0)
Enfoques     Open Access  
Engenharia Agrícola     Open Access   (SJR: 0.305, CiteScore: 1)
Engenharia Sanitaria e Ambiental     Open Access   (SJR: 0.218, CiteScore: 0)
Ensaio Avaliação e Políticas Públicas em Educação     Open Access   (Followers: 1, SJR: 0.254, CiteScore: 0)
Ensayos de Economía     Open Access   (Followers: 2)
Ensayos Revista de Economía     Open Access   (Followers: 2)
Entomologia y Vectores     Open Access   (Followers: 2)
Entre Ciencia e Ingeniería     Open Access   (Followers: 2)
Epidemiologia e Serviços de Saúde     Open Access  
Escritos de Psicología : Psychological Writings     Open Access   (Followers: 2)
Estudios Atacameños     Open Access   (Followers: 2, SJR: 0.446, CiteScore: 1)
Estudios Constitucionales     Open Access   (Followers: 5, SJR: 0.319, CiteScore: 0)
Estudios de Cultura Maya     Open Access   (Followers: 2, SJR: 0.272, CiteScore: 0)
Estudios de Economía     Open Access   (SJR: 0.121, CiteScore: 0)
Estudios de historia moderna y contemporánea de México     Open Access   (SJR: 0.101, CiteScore: 0)
Estudios Economicos     Open Access  
Estudios Filologicos     Open Access   (SJR: 0.107, CiteScore: 0)
Estudios Fronterizos     Open Access   (Followers: 1)
Estudios internacionales     Open Access   (Followers: 5)
Estudios Pedagogicos (Valdivia)     Open Access   (Followers: 1, SJR: 0.338, CiteScore: 0)
Estudios Políticos     Open Access  
Estudios Sociales     Open Access   (Followers: 2)
Estudios sociales : Revista de alimentación contemporánea y desarrollo regional     Open Access   (Followers: 2)
Estudios Socioterritoriales : Revista de Geografía     Open Access  
Estudos Afro-Asiáticos     Open Access   (Followers: 2)
Estudos Avançados     Open Access   (SJR: 0.232, CiteScore: 0)
Estudos de Psicologia (Campinas)     Open Access   (Followers: 1, SJR: 0.233, CiteScore: 0)
Estudos de Psicologia (Natal)     Open Access   (SJR: 0.117, CiteScore: 0)
Estudos Econômicos     Open Access   (SJR: 0.204, CiteScore: 0)
Estudos Históricos     Open Access   (Followers: 1)
EURE (Santiago) - Revista Latinoamericana de Estudios Urbano Regionales     Open Access   (SJR: 0.38, CiteScore: 1)
Ex aequo     Open Access  
FEM : Revista de la Fundación Educación Médica     Open Access  
Fides et Ratio : Revista de Difusión Cultural y Científica     Open Access   (Followers: 2)
Fisioterapia e Pesquisa     Open Access  
Fisioterapia em Movimento     Open Access  
Fitosanidad     Open Access  
Floresta e Ambiente     Open Access   (Followers: 1, SJR: 0.3, CiteScore: 0)
Folios     Open Access  
Food Science and Technology (Campinas)     Open Access   (Followers: 1, SJR: 0.467, CiteScore: 1)
Formación Universitaria     Open Access   (Followers: 4, SJR: 0.213, CiteScore: 1)
Frónesis     Open Access   (Followers: 2)
Frontera Norte     Open Access  
Gaceta Médica Boliviana     Open Access  
Gaceta Médica Espirituana     Open Access  
Galáxia (São Paulo)     Open Access  
Gayana (Concepcion)     Open Access   (SJR: 0.236, CiteScore: 0)
Gayana. Botanica     Open Access   (SJR: 0.234, CiteScore: 0)
Genetics and Molecular Biology     Open Access   (Followers: 15, SJR: 0.638, CiteScore: 2)
Geofísica internacional     Open Access   (SJR: 0.312, CiteScore: 1)
Gerokomos     Open Access   (Followers: 1, SJR: 0.257, CiteScore: 0)
Gestão & Produção     Open Access   (SJR: 0.156, CiteScore: 0)
Gestión y Política Pública     Open Access   (Followers: 2, SJR: 0.106, CiteScore: 0)
Hacia la Promoción de la Salud     Open Access  
Hallazgos     Open Access   (Followers: 1)
Hidrobiológica     Open Access   (SJR: 0.166, CiteScore: 0)
Historia     Open Access   (Followers: 2)
Historia (Santiago)     Open Access   (Followers: 1, SJR: 0.162, CiteScore: 0)
História (São Paulo)     Open Access   (SJR: 0.11, CiteScore: 0)
História, Ciências, Saúde - Manguinhos     Open Access   (Followers: 2, SJR: 0.144, CiteScore: 0)
Hoehnea     Open Access  
Horizonte Sanitario     Open Access   (Followers: 2)
Horizontes Antropológicos     Open Access   (Followers: 3, SJR: 0.233, CiteScore: 0)
Horticultura Brasileira     Open Access   (SJR: 0.605, CiteScore: 1)
HTS Theological Studies     Open Access   (Followers: 8, SJR: 0.448, CiteScore: 0)
Humanidades Médicas     Open Access  
IDESIA : Revista de Agricultura en Zonas Áridas     Open Access   (SJR: 0.223, CiteScore: 0)
Iheringia. Série Zoologia     Open Access   (Followers: 1, SJR: 0.26, CiteScore: 1)
Íkala : Revista de Lenguaje y Cultura     Open Access   (SJR: 0.112, CiteScore: 0)
Image & Text     Open Access   (Followers: 2)
Index de Enfermeria     Open Access   (Followers: 5, SJR: 0.113, CiteScore: 0)
Indo-Pacific J. of Phenomenology     Open Access   (Followers: 1)
Infectio     Open Access   (SJR: 0.133, CiteScore: 0)
Información Tecnológica     Open Access   (SJR: 0.197, CiteScore: 0)
Ingeniare : Revista Chilena de Ingenieria     Open Access   (Followers: 1, SJR: 0.239, CiteScore: 0)
Ingeniería Electrónica, Automática y Comunicaciones     Open Access  
Ingeniería Hidráulica y Ambiental     Open Access  
Ingeniería Industrial     Open Access  
Ingeniería Mecánica     Open Access   (Followers: 4)
Ingenieria Mecánica. Tecnologia y Desarrollo     Open Access   (Followers: 3)
Ingeniería y Competitividad     Open Access  
Ingenieria y Universidad     Open Access   (Followers: 1, SJR: 0.161, CiteScore: 1)
Ingeniería, Investigación y Tecnología     Open Access   (Followers: 1)
Innovar     Open Access   (SJR: 0.118, CiteScore: 0)
Interações (Campo Grande)     Open Access  
Interface - Comunicação, Saúde, Educação     Open Access   (Followers: 1, SJR: 0.417, CiteScore: 0)
Intersticios Sociales     Open Access   (Followers: 2)
Intervención     Open Access   (Followers: 2)
Intervención Psicosocial     Open Access   (SJR: 0.381, CiteScore: 1)
Intl. Brazilian J. of Urology     Open Access   (Followers: 4, SJR: 0.367, CiteScore: 1)
Intl. J. of Morphology     Open Access  
Intl. J. of Odontostomatology     Open Access   (Followers: 1)
Intl. Law: Revista Colombiana de Derecho Internacional     Open Access   (Followers: 3)
Investigación Administrativa     Open Access   (Followers: 2)
Investigación Bibliotecológica     Open Access   (Followers: 6, SJR: 0.274, CiteScore: 0)
Investigación Económica     Open Access   (Followers: 4, SJR: 0.132, CiteScore: 0)
Investigación y Desarrollo     Open Access   (Followers: 1)
Investigación y Educación en Enfermería     Open Access   (Followers: 1, SJR: 0.198, CiteScore: 0)
Investigaciones Geográficas     Open Access   (SJR: 0.246, CiteScore: 0)
Investigaciones Marinas     Open Access  
Iteckne     Open Access  
Iuris Tantum Revista Boliviana de Derecho     Open Access  
Ius et Praxis     Open Access   (SJR: 0.283, CiteScore: 0)
Izquierdas     Open Access   (SJR: 0.188, CiteScore: 0)
Iztapalapa : Revista de ciencias sociales y humanidades     Open Access   (Followers: 2)
J. of Applied Oral Science     Open Access   (SJR: 0.645, CiteScore: 2)
J. of Applied Research and Technology     Open Access   (SJR: 0.255, CiteScore: 1)
J. of Coloproctology     Open Access   (SJR: 0.167, CiteScore: 0)
J. of Energy in Southern Africa     Open Access   (Followers: 3, SJR: 0.249, CiteScore: 1)
J. of Epilepsy and Clinical Neurophysiology     Open Access   (Followers: 7)
J. of Microwaves, Optoelectronics and Electromagnetic Applications     Open Access   (Followers: 11, SJR: 0.146, CiteScore: 1)
J. of Seed Science     Open Access   (Followers: 1)
J. of Soil Science and Plant Nutrition     Open Access   (Followers: 11, SJR: 0.823, CiteScore: 2)
J. of Technology Management & Innovation     Open Access   (Followers: 5, SJR: 0.271, CiteScore: 1)
J. of the Brazilian Chemical Society     Open Access   (Followers: 2, SJR: 0.357, CiteScore: 1)
J. of the Brazilian Society of Mechanical Sciences     Open Access   (Followers: 2)
J. of the Chilean Chemical Society     Open Access   (Followers: 2, SJR: 0.201, CiteScore: 1)
J. of the Mexican Chemical Society     Open Access   (Followers: 2, SJR: 0.214, CiteScore: 1)
J. of the Selva Andina Research Society     Open Access   (Followers: 3)
J. of the South African Institution of Civil Engineering     Open Access   (Followers: 2, SJR: 0.174, CiteScore: 0)
J. of the Southern African Institute of Mining and Metallurgy     Open Access   (Followers: 6)
J. of Venomous Animals and Toxins     Open Access   (Followers: 2)
JISTEM : J. of Information Systems and Technology Management     Open Access   (Followers: 7)
Jornal Brasileiro de Nefrologia     Open Access   (SJR: 0.334, CiteScore: 1)
Jornal Brasileiro de Patologia e Medicina Laboratorial     Open Access   (SJR: 0.143, CiteScore: 0)
Jornal Brasileiro de Pneumologia     Open Access   (SJR: 0.448, CiteScore: 1)
Jornal Brasileiro de Psiquiatria     Open Access   (Followers: 2, SJR: 0.224, CiteScore: 0)
Jornal da Sociedade Brasileira de Fonoaudiologia     Open Access  
Jornal de Pneumologia     Open Access  
Jornal Vascular Brasileiro     Open Access   (SJR: 0.136, CiteScore: 0)
Justicia Juris     Open Access  
Kriterion: Revista de Filosofia     Open Access   (Followers: 1, SJR: 0.114, CiteScore: 0)
Kronos : Southern African Histories     Open Access   (Followers: 6)
La ventana. Revista de estudios de género     Open Access  
La zaranda de ideas     Open Access   (Followers: 1)
Laboreal     Open Access  
Lankesteriana     Open Access   (SJR: 0.458, CiteScore: 1)
Latin American Applied Research     Open Access   (Followers: 1)
Latin American J. of Aquatic Research     Open Access   (SJR: 0.289, CiteScore: 1)
Latin American J. of Economics     Open Access   (Followers: 1, SJR: 0.127, CiteScore: 0)
Latin American J. of Solids and Structures     Open Access   (Followers: 4, SJR: 0.522, CiteScore: 1)
Latinoamérica. Revista de estudios Latinoamericanos     Open Access   (Followers: 2)
Lecturas de Economía     Open Access  
Letras Históricas     Open Access   (Followers: 2)
Límite : Revista Interdisciplinaria de Filosofía y Psicología     Open Access  
Linguagem em (Dis)curso     Open Access  
Lingüística     Open Access   (SJR: 0.13, CiteScore: 0)
Lingüística y Literatura     Open Access   (Followers: 1)
Literatura y Lingüística     Open Access   (Followers: 1, SJR: 0.13, CiteScore: 0)
Lua Nova : Revista de Cultura e Política     Open Access   (SJR: 0.274, CiteScore: 0)
Luna Azul     Open Access  
Machado de Assis em Linha     Open Access   (SJR: 0.101, CiteScore: 0)
Madera y Bosques     Open Access   (Followers: 2)
Maderas. Ciencia y tecnología     Open Access   (Followers: 2, SJR: 0.546, CiteScore: 1)
Magallania     Open Access   (SJR: 0.354, CiteScore: 0)
Mana - Estudos de Antropologia Social     Open Access   (Followers: 2, SJR: 0.355, CiteScore: 0)
Manuscrito     Open Access  

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Maderas. Ciencia y tecnología
Journal Prestige (SJR): 0.546
Citation Impact (citeScore): 1
Number of Followers: 2  

  This is an Open Access Journal Open Access journal
ISSN (Print) 0718-221X - ISSN (Online) 0717-3644
Published by SciELO Homepage  [893 journals]
  • Assessment of physical and mechanical properties of Papua New Guinea
           timber species

    • Abstract: Abstract: A comprehensive testing program has been developed to assess different physical and mechanical properties of 26 commercial and lesser-known Papua New Guinea species from secondary and plantation forests. The impact of log position in a tree on the mechanical properties has also been assessed to optimize the utilization of timbers along the value chain. The results showed that stiffness and bending strength tend to decrease or remain unchanged along the stem. Shear strength and Janka hardness displayed a similar trend to a lesser extent where the position in the tree had a limited impact on compression strength properties. Thus, segregating based on log position can be of interest where desired mechanical properties and costs associated with segregating justify optimum mechanical properties for the intended end use. The properties of selected species from plantations and regrowth forests were generally lower than those found in the literature for timbers from old-growth forests. The size of specimens tested, the amount and provenance of tested material, and some adaptive traits for tropical tree species are some factors potentially explaining observed differences. However, a comparison with recent studies tends to confirm the overall reduction of physical and mechanical properties when compared with old-growth forests timbers.
       
  • The chemical and morphological properties of oleaster

    • Abstract: Abstract: This study investigated the morphological characteristics and chemical properties of the wood and the chemical properties of the bark of the oleaster (Elaeagnus angustifolia) tree, which grows in a variety of climatic conditions in different regions of Turkey. The study materials were taken from three different regions of Turkey having different climatic conditions and elevations with the aim to determine the chemical properties of the bark and wood and the fiber properties of the wood. According to chemical analyses, no significant differences in the core components of the cell wall were observed between the heartwood and the sapwood. The samples collected from the Çankiri region had the highest holocellulose content (84,9%), while the proportions of alpha cellulose (52,3%) and lignin (24,0%) in samples taken from the Balikesir region were found to be higher than in samples from the other regions. According to the sugar analysis, glucose and xylose were found to be higher in the heartwood than in the sapwood. When the sugar ratios were evaluated by region, the glucose and xylose ratios were the highest in the Çankiri region (43,7% and 22,8%) and the lowest in the Konya region (38,3% and 20,5%). When looking at the inner bark (phloem) and outer bark (rhylidome) rates, the amounts of holocellulose and alpha cellulose were higher in the inner bark and the lignin rates were higher in the outer bark. The wood solubility values for cold and hot water, ethyl alcohol and the 1% NaOH were highest in samples from the Çankiri region and lowest in those from the Konya region, whereas bark solubility rates were highest in the samples taken from the Balikesir region. When morphological characteristics were examined, no obvious differences were seen among the regions in terms of the fiber length, fiber width, lumen diameter or double wall thickness. Upon further investigation, it was determined that the oleaster tree wood was suitable for papermaking, but that the produced paper would exhibit a low resistance value because the average felting rate among the three growing regions was low (39,87%).
       
  • Characterization of the wood properties of Cedrelinga cateniformis as
           substitute for timbers used for window manufacturing and outdoor
           applications

    • Abstract: Abstract: Cedrelinga cateniformis (tornillo) is a timber species of the South American Amazon Basin. In its natural distribution area, the wood has various local uses, such as furniture, art work, door and window frames, and light construction. In order to promote this lesser known species for high valued applications on the international market, wood anatomical, topochemical and physical/mechanical studies were carried out to characterize the wood properties. The topochemical distribution of the lignin and phenolic extractives in the tissue were studied by means of cellular UV microspectrophotometry (UMSP). The results of the structural and topochemical analyses were compared with the interrelation of certain anatomical and subcellular structures as well as the chemical composition with regard to the physical and mechanical properties. The natural durability of the mature heartwood was analyzed according to the European Standards and is resulting in a durability class 1 against basidiomycetes. Based on the findings of the comprehensive investigations concerning physical and biological features, e.g. the dimensional stability and durability, Cedrelinga cateniformis is ideally suited as a substitute for overexploited tropical woods currently used in Europe for wooden window frames and other above ground outdoor applications and thus can contribute to increase the value-added production in Peruvian forests.
       
  • Carbon fiber-reinforced polymers as a tensile reinforcement of the Pinus
           elliotti and Manilkara huberi wood species

    • Abstract: Abstract: In wood structures, the elements subjected to bending stresses, such as the beams, present a fracture initiated in the tensile region, and under these conditions, the use of laminated composite materials is presented as an alternative solution in the form of repair or reinforcement. This research aimed to evaluate the influence of the use of carbon fibers laminated composites in tensile reinforcement in the direction parallel to grain of Pinus elliotti and Manilkara huberi wood species. The Viapol two-component epoxy adhesive was used in the lamination and fixation of the unidirectional carbon fiber in the wood species. Ten specimens with no defects (reference) and 10 specimens were prepared for each crack length (25 and 50mm) with and without the reinforcement (60mm × 50mm) by the laminated composite. The tensile tests were performed in accordance with the requirements of the Brazilian standard. From the results of the statistical analysis, the use of the carbon fiber composite was able to restore the tensile strength of the cracked samples (partial or total) in relation to samples without defects, demonstrating the potential of the laminates in carbon fibers as an alternative solution in repair for both wood species.
       
  • Effect of applying finishing products and sanding on the surface of marupa
           wood

    • Abstract: Abstract: The effect of applying cetol and finishing varnish products and sanding on the surface roughness and colour of marupa (Simarouba amara) wood was evaluated. Three coats of each product were applied and two sandpaper grits were used, 280 and 320). The analyzes were performed on untreated samples and between each coat of products in order to analyze the effect of sanding, the products and the number of coats. According to colorimetry, the L* value for the control treatment was 82,83 and the treatments reduced the L* to 61,70 on average for the cetol treatment and 77,09 for the varnish treatment, showing that the cetol darkened the wood more than the varnish. The yellowish and reddish pigmentations became more intense according to the positive values of Δa* and Δb*, especially after applying the cetol. The total colour variation ΔE average was 40,79 for the cetol treatment and 9,83 for the varnish treatment, confirming a much more significant colour change in the cetol treatment. Sanding with different grits did not significantly alter the surface colour. The product application made the wood surface smoother, and was noticeable from the second coat. Sanding reduced roughness on the wood surface, but the finishing product was the largest source of variation.
       
  • The influence of ultraviolet radiation on the colour of
           thermo-mechanically modified beech and oak wood

    • Abstract: Abstract: The study examined the influence of ultraviolet radiation on the colour of thermo-mechanically modified beech (Fagus sylvatica ) and oak (Quercus robur). The wood colour parameters were measured using the mathematical CIE L*a*b* and L*C*h colour space models. The higher the temperature of thermo-mechanical treatment, the least susceptible beech and oak wood was to a change in L*, a* and b* under the influence of light irradiation. The greatest changes in the colour of non-densified and densified beech and oak wood occurred after 20 h of light irradiation. The higher the temperature of thermo-mechanical treatment, the smaller were the total changes in the colour of beech and oak wood under the influence of ultraviolet radiation. The total changes in the colour of beech densified at temperatures of 100°C and 150°C that took place under the influence of ultraviolet radiation were twice as high as in the case of densified oak wood. The colour of oak wood modified at a temperature of 200°C did not change significantly in 300 h of light irradiation.
       
  • Mechanical behavior of dowel connection for timber-concrete composite
           rural bridges

    • Abstract: Abstract: This study focuses on the evaluation of the mechanical behavior of two types of connections for intended use in rural Timber-Concrete Composite traffic bridges. The two connection types used were the “X” type connection - XD and the dowel type connection - PD. Firstly, static shear tests in small-scale specimens were performed in both connection types and higher results were obtained for the XD series, both for stiffness and load carrying capacity. Secondly, the PD connection was chosen, based on practical and economical aspects, for further testing also in small-scale specimens, including cyclic tests. The influence of the number of cycles in the connection stiffness and load carrying capacity was evaluated. It was concluded that the load carrying capacity increased after the application of a pre-defined number of load cycles and that the connection stiffness increased 80,6% and 34,1% after 10000 and 1000 cycles, respectively, for different applied load levels. Also the increase of load level in the cyclic tests affected the performance of the connection, leading to a decrease in stiffness.
       
  • Effect of press temperature on some properties of cement bonded
           particleboard

    • Abstract: Abstract: It is known that there is a correlation between hydration heat and physico-mechanical properties of wood based cement panels. Cement hydration is affected by many variables, such as chemical composition, water/cement ratio, wood/cement ratio, wood chemical properties, mineral additions and producing conditions. This study mainly aimed to investigate the effects of press temperature on some properties of three-layer cement bonded particleboard made from the particles of spruce (Picea orientalis) and poplar (Populus tremula). For this purpose, a total of 16 experimental board groups with 1200 kg/m3 target density and 1/3 wood-cement ratio were produced at the press temperatures of (20, 30, 40, 50, 60, 70 and 80) °C. As cement curing accelerator, CaCl2 was used at a rate of 5 % (cement weight basis). The physical, mechanical and thermal properties of the boards were determined. The results indicated that the press temperature substantially affected the properties of cement-bonded particleboard depending on the wood species. In the light of this study, the optimum temperatures in producing of cement-bonded particleboard were found as 40 °C for poplar wood and 60 °C for spruce wood.
       
  • Integral use of Eucalyptus globulus in a double stage biorefinery
           scheme

    • Abstract: Resumen: Se han aplicado dos tratamientos previos al proceso de pasteado etanol-sosa sobre madera de Eucalyptus globulus para evaluar su influencia sobre las propiedades de las pastas celulósicas obtenidas. Se aplica una primera etapa optimizada de autohidrólisis para maximizar la extracción de derivados hemicelulósicos preservando el glucano, seguida de una deslignificación enzimática mediante un sistema lacasa/mediador (siringaldehído). Se aplican diseños experimentales para la optimización de los procesos. Las condiciones de operación óptimas en la etapa de deslignificación enzimática han sido: concentración de lacasa 18,5 U/g, concentración de siringaldehído 1,5 %, temperatura 45 ºC y tiempo de operación 60 min., con las cuales se alcanza una eliminación del 16,8 % de la lignina existente en la materia prima y se afecta ligeramente al glucano (conservando entre el 82,2 % y 89,7 % del glucano inicial). Paralelamente se obtienen dos fases líquidas valorizables, ricas en derivados hemicelulósicos y polifenólicos. En este esquema de proceso para obtención de pasta celulósica etanol-sosa a partir de madera eucalipto requiere una menor concentración de reactivos químicos, menores tiempos de operación y temperaturas más bajas, lo que supone una mejora económica y medioambiental respecto del proceso convencional de pasteado.Abstract: Two previous treatments have been applied to the ethanol-soda paste process on Eucalyptus globulus wood to evaluate its influence on the properties of the obtained cellulose pulps. The treatments consisted of a first optimized stage of autohydrolysis (temperature: 180 ºC, time: 30 min) to obtain the maximum extraction rate of hemicellulosic derivatives preserving the glucan, followed by enzymatic oxidative delignification by a laccase/mediator system (syringaldehyde). Experimental designs have been applied for the optimization of processes. The optimum operating conditions in the enzymatic delignification stage were: Lacasse concentration 18,5 U/g, concentration of syringaldehyde 1,5 %, temperature 45 ºC and operating time 60 min., with which an elimination of the 16,8% of the existing lignin in the raw material and slightly affects the glucan (it is conserved between 82,2 % and 89,7 % of the initial glucan). Two liquid, recoverable phases are obtained, rich in hemicellulose and polyphenolic derivatives. In this process scheme to obtain ethanol-soda cellulosic pulp from eucalyptus wood requires a lower concentration of chemical reagents, shorter operating times and lower temperatures, which is an economic and environmental improvement over the conventional pulping process.
       
  • Evaluation of different plant derived oils as wood preservatives against
           subterranean termite Odontotermes obesus

    • Abstract: Abstract: The study assessed the effect of jatropha, linseed, eucalyptus, neem and jojoba oils on protection of three wood species (Acacia nilotica, Dalbergia sissoo and Pinus wallichiana) against termite attack by Odontotermes obesus. Conditioned and pre-weighed blocks of each wood species were vacuum-pressure impregnated with a 15% concentration of the oil-ethanol solutions. Resistance of treated and untreated wood against termites was tested under laboratory as well as field conditions using choice and no-choice tests. Oil treated wood showed significant reductions in weight loss compared to control treatments. Complete termite mortality was recorded for all oil treatments except eucalyptus oil. Linseed oil showed good results in each treatment in terms of feeding resistance as well as mortality of termites followed by neem, jatropha, jojoba and eucalyptus oil. The lower weight losses were found in both choice and no-choice field tests for linseed oil treated Dalbergia sissoo while untreated Pinus wallichiana sapwood had the greater weight loss. It was observed that the oil retention was significantly more in sapwood than in heartwoods. The retention of oils justified that wood with high oil retention showed more resistance against the termite except eucalyptus oil treatment of Pinus wallichiana.
       
 
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