Mechanical properties of wood from Pinus sylvestris L. treated with Light Organic Solvent Preservative and with waterbone Copper Azole

El objetivo del estudio es determinar el efecto de tratamiento de la madera de Pinus sylvestris con sustancias protectoras en las propiedades mecánicas. Para ello se utilizan 40 muestras de madera libre de defectos de Pinus sylvestris L. tratándose con protectores orgánicos (Vacsol Azure WR 2601) 50 con protectores hidrosolubles (Tanalith E 3492) y 40 muestras de control sin tratamiento. Se evaluó la resistencia mecánica a la flexión estática, módulo de elasticidad y la fuerza de compresión paralela a la fibra fueron comparados con madera no tratada. El análisis de regresión entre la penetración y la fuerza de compresión paralela se realizó con las muestras tratadas con conservante a base de agua. Resultados principales: Los resultados indican que la madera tratada (con cualquiera de los productos) presenta un aumento estadísticamente significativo de la resistencia mecánica en todas las tres características mecánicas. Los resultados obtenidos difieren de estudios anteriores llevada a cabo por otros autores. No hubo correlación entre la resistencia a la compresión en paralelo y el grado de impregnación de la madera con base de agua de cobre azoles. La explicación más probable para estos resultados se refiere a cambios en la presión durante el tratamiento. El uso de muestras de control no tratadas en lugar de las muestras tratadas sólo con agua es más probable para producir resultados significativos en los estudios de resistencia mecánica . La investigación pone de relieve que la madera tratada presenta un aumento estadísticamente significativo en el Modulo de Elasticidad, módulo de rotura a la flexión estática y resistencia a la compresión paralela. No hubo correlación entre la resistencia a la compresión en paralelo y el grado de impregnación con conservante hidrosoluble.

Effect of carbon fibres on the mechanical properties and corrosion levels of reinforced portland cement mortars

The changes in mechanical properties of portland cement mortars due to the addition of carbon fibres (CF) to the mix have been studied. Compression and flexural strengths have been determined in relation to the amount of fibres added to the mix, water/binder ratio, curing time and porosity. Additionally, the corrosion level of reinforcing steel bars embedded in portland cement mortars containing CF and silica fume (SF) have also been investigated and reinforcing steel corrosion rates have been determined. As a consequence of the large concentration of oxygen groups in CF surface, a good interaction between the CF and the water of the mortar paste is to be expected. A CF content of 0.5% of cement weight implies an optimum increase in flexural strength and an increase in embedded steel corrosion.

Influence of using slag cement on the microstructure and durability related properties of cement grouts for micropiles

Today, the use of micropiles for different applications has become very common. In Spain, the cement grouts for micropiles are prepared using ordinary Portland cement and w:c ratio 0.5, although the micropiles standards do not restrict the cement type to use, provided that it reaches a certain compressive strength. In this study, the influence of using slag cement on the microstructure and durability related properties of cement grouts for micropiles have been studied until 90 hardening days, compared to an ordinary Portland cement. Finally, slag cement grouts showed good service properties, better than ordinary Portland cement ones.

Efficiency of a conductive cement-based anodic system for the application of cathodic protection, cathodic prevention and electrochemical chloride extraction to control corrosion in reinforced concrete structures

This article describes the research carried out regarding the application of cathodic protection (CP) and cathodic prevention (CPrev), in some cases with a pre-treatment of electrochemical chloride extraction (ECE), on representative specimens of reinforced concrete structures, using an anodic system consisting of a graphite-cement paste applied as a coating on the surface. The aim of this research is to find out the competence of this anode for the aforementioned electrochemical treatments. The efficiency of this anode has been clearly demonstrated, as well as its capability to apply a combined process of ECE and after CP.

Impedance spectroscopy study of the effect of environmental conditions in the microstructure development of OPC and slag cement mortars

In this work, the microstructure of mortars made with an ordinary Portland cement and slag cement has been studied. These mortars were exposed to four different constant temperature and relative humidity environments during a 180-day period. The microstructure has been studied using impedance spectroscopy, and mercury intrusion porosimetry as a contrast technique. The impedance spectroscopy parameters make it possible to analyze the evolution of the solid fraction formation for the studied mortars and their results are confirmed with those obtained using mercury intrusion porosimetry. The development of the pore network of mortars is affected by the environment. However, slag cement mortars are more influenced by temperature while the relative humidity has a greater influence on the OPC mortars. The results show that slag cement mortars hardened under non-optimal environments have a more refined microstructure than OPC mortars for the studied environmental conditions.

Prediction of blackwood wood and pulp quality parameters using NIR-PLS-R spectral modelling : wavenumber ranges and smoothing points

Só está disponível o resumo.

A software tool for accurate assessment of costs and CO2 emissions in wood transport using OpenStreetMap©

Costs and environmental impacts are key elements in forest logistics and they must be integrated in forest decision-making. The evaluation of transportation fuel costs and carbon emissions depend on spatial and non-spatial data but in many cases the former type of data are dicult to obtain. On the other hand, the availability of software tools to evaluate transportation fuel consumption as well as costs and emissions of carbon dioxide is limited. We developed a software tool that combines two empirically validated models of truck transportation using Digital Elevation Model (DEM) data and an open spatial data tool, specically OpenStreetMap©. The tool generates tabular data and spatial outputs (maps) with information regarding fuel consumption, cost and CO2 emissions for four types of trucks. It also generates maps of the distribution of transport performance indicators (relation between beeline and real road distances). These outputs can be easily included in forest decision-making support systems. Finally, in this work we applied the tool in a particular case of forest logistics in north-eastern Portugal

Wood and garden : notes and thoughts, practical and critical, of a working amateur /

Includes index.

Morse's manual of art : a self teacher in all branches of deocrative art, embracing almost every variety of painting and drawing, on china, glass, velvet, canvas, paper and wood : the secret of all glass transparencies, sketching from nature, pastel and crayon drawing, etc. : illustrated /

Mode of access: Internet.

Removal of wood-derived toxics from pulping and bleaching wastes /

Grant no. R-803525-04.

Practical concrete-block making; a simple practical treatise for the workman explaining the selection of the materials and the making of substantial concrete blocks and cement brick, together with directions for making molds and remarks on how to obtain the best architectural effects,

Mode of access: Internet.

A full and correct report of the testimony given before the Joint committee of the legislature of 1842, inquiring into the charges of bribery and corruption by the banks during the session of 1840 : together with the proceedings has at the bar of the House of representatives, in the case of George Handy, one of the directors of the United States bank: and copies of the original letters of Daniel M. Brodhead, Joseph Solms, Samuel R. Wood ... [and others] as the same were presented in evidence, in the progress of the investigation; accompanied by the report of the committee /

Mode of access: Internet.

A dictionary of Roman and Greek antiquities : with nearly 2000 engravings on wood from ancient originals illustrative of the industrial arts and social life of the Greeks and Romans /

First edition published 1849 under title: Illustrated companion to the Latin dictionary and Greek lexicon.