Impact of Wetting–Drying Cycles on the Mechanical Properties and Microstructure of Wood Waste–Gypsum Composites

Large amounts of wood waste are generated each year in the world. In an attempt to identify a good recovery option for those residues, wood waste from construction and demolition works were used as raw materials in gypsum plasters. However, wood is a biodegradable material which implies that the products or materials that contain it are susceptible to su ering an important deterioration, due to exposure in certain environments. For that reason, the aim of this work was to simulate the e ects that, in the long term, the atmospheric exposure of wood waste–gypsum composites would have. To do that, the plasters were subjected to 5, 10, and 15 wetting–drying cycles in a climatic chamber. In this study, the density, flexural and compressive strength, and ultrasonic velocity of these composites were determined by the influence of the aging process on their mechanical properties. Furthermore, in order to detect changes on their internal structure, scanning electron microscopy tests (SEM) were used. The results showed that they were suitable to be used as indoor coverings of buildings. However, a treatment to reduce the moisture absorption of the wood waste must be studied if mixtures with high percentages of wood shavings (WS20) are used in wet rooms

Characterisation of recycled ceramic mortars for use in prefabricated beam-filling pieces in structural floors

This study analyses a procedure to manufacture mortars with different percentages of ceramic waste as partial replacement for aggregates. The study also examines the physical, chemical and mechanical properties of the new mortars, analysing substitution ratios that range from 10% to 50%. Prior to this, all the materials used in the production of the mortar were characterised using X-ray diffraction (XRD) and fluorescence (XRF). The objective was to determine the similarity between different types of ceramic waste, as well as the differences in the minerology and chemical composition with the aggregate. The results of the study show that it is possible to obtain mortars with lower densities compared to the same product with no recycled content. The product’s characteristics make it ideal for the manufacture of prefabricated components for structural floors for rehabilitation works. Finally, the pieces are used in a real rehabilitation case study, highlightining the structural advantages.Caracterización de morteros con cerámica reciclada y su uso en piezas prefabicadas para entrevigado de forjados. Este trabajo analiza morteros con diferentes porcentajes de cerámica reciclada como sustituto parcial de la arena. Además el estudio examina las propiedades físicas, químicas y mecánicas de los nuevos morteros, empleando diferentes porcentajes de sustitución (10% - 50%). Con anterioridad, se caracterizaron todos los materiales empleados en este trabajo mediante difracción y fluorescencia de rayos-X. El objetivo fue determinar las diferencias y similitudes en la composición química y mineralógica de los distintos tipos de residuos cerámicos y del resto de áridos utilizados. Los resultados muestran que es posible obtener morteros con menor densidad frente a las muestras sin contenido reciclado. Sus características los hacen idóneos para la creación de piezas prefabricadas de entrevigado para rehabilitación de forjados. Finalmente. Las piezas se usaron en un caso de estudio real, destacando las ventajas estructurales que conlleva su uso

Análisis Coste-beneflcio del Programa de Detección Precoz de Enfermedades Metabólicas en la Comunidad Autónoma Vasca

ResumenSe estudia la rentabilidad social del Programa de Detección Precoz y Tratamiento de dos enfermedades metabólicas, la fenilcetonuria y el hipotiroidismo congènito, en la Comunidad Autónoma Vasca, en vigor desde noviembre de 1982.La técnica utilizada es el análisis coste-beneficio. Los costes sociales de detección y tratamiento se comparan con los beneficios sociales de la prevención del retardo mental (1984 y 1985). Los Índices beneficio-coste (BC) y el valor actual neto (VAN) muestran que el programa es rentable excepto cuando los valores futuros de costes y beneficios son descontados a tasas elevadas. Los resultados del estudio son consistentes con los obtenidos por otras evaluaciones económicas de este tipo de programas.En términos de coste-efectividad, el coste de prevenir un caso de subnormalidad se estimó en 3.300.000 ptas., lo que podría interpretarse como un limite inferior a la valoración social de la prevención de la deficiencia mental.SummaryThe efficiency of an early screening and treatment Programme for two Metabolic disorders, phenylketonuria and congenita! hypothyroidism running since November 1982 in the Basque Country, is analysed.The cost-benelit analysis technique is used. The social costs of screening and treatment are compared with the social benefits for the prevention of mental handicap (1984-1985). Benefit-cost ratios and the net present value shows the social efficiency of the programme except when high discount rates have been used for discounting future costs and benefits. That conclusion is consistent with the results of other cost-benefit studies.In terms of cost-effectiveness the cost per child with mental handicap prevented was estimated on 3.300.000 ptas. That could be seen as the lowest social value for the prevention of a child with mental handicap

Unveiling the true costs and societal impacts of moderate-to-severe atopic dermatitis in Europe

Atopic dermatitis (AD) is a chronic, auto-immune condition that imposes a high burden on individuals, society, and the healthcare system. Approximately 4.4% of adults and up to 18.6% of children/adolescents have AD in Europe, with 20% of all cases accounting for moderate-to-severe forms. This form of the condition in adults results in annual societal costs across Europe of an estimated euro30 billion; euro15.2 billion related to missed workdays or reduced work productivity, euro10.1 billion related to direct medical costs and euro4.7 billion related to personal expenditure of patients/families. AD can also substantially impact physical, emotional, and social quality-of-life. Several studies have shown the debilitating itch-scratch cycle is the main cause of the multifaceted burden, as it causes substantial sleep deprivation and stigmatisation due to the physical appearance of the skin, and confidence issues. These factors lead to psychosocial issues and can cumulate over time and prohibit patients reaching their 'full life potential'. Despite this, many patients with the condition are undertreated, resulting in uncontrolled symptoms and a further strain placed on patients, society, and the economy. The authors of this White Paper comprise the European Atopic Dermatitis Working Group, which is a network of international specialists with expertise in dermatology and healthcare policy decisions. Their programme of action is focused on harnessing their expertise to build consensus, advance research, share knowledge, and ultimately seek to improve AD care outcomes through achieving long-term symptom control. This White Paper presents a systematic evaluation of the overall financial and humanistic burden of moderate-to-severe AD and the current challenges that exist with AD care. It introduces recommendations for how, collaboratively, key stakeholders and policy makers can support improvements in AD management to achieve better disease control, thus reducing the costs and associated burden placed on individuals, society, and the economy

Caracterización de morteros con cerámica reciclada y su uso en piezas prefabicadas para entrevigado de forjados

This study analyses a procedure to manufacture mortars with different percentages of ceramic waste as partial replacement for aggregates. The study also examines the physical, chemical and mechanical properties of the new mortars, analysing substitution ratios that range from 10% to 50%. Prior to this, all the materials used in the production of the mortar were characterised using X-ray diffraction (XRD) and fluorescence (XRF). The objective was to determine the similarity between different types of ceramic waste, as well as the differences in the minerology and chemical composition with the aggregate. The results of the study show that it is possible to obtain mortars with lower densities compared to the same product with no recycled content. The product’s characteristics make it ideal for the manufacture of prefabricated components for structural floors for rehabilitation works. Finally, the pieces are used in a real rehabilitation case study, highlightining the structural advantages.Este trabajo analiza morteros con diferentes porcentajes de cerámica reciclada como sustituto parcial de la arena. Además el estudio examina las propiedades físicas, químicas y mecánicas de los nuevos morteros, empleando diferentes porcentajes de sustitución (10% - 50%). Con anterioridad, se caracterizaron todos los materiales empleados en este trabajo mediante difracción y fluorescencia de rayos-X. El objetivo fue determinar las diferencias y similitudes en la composición química y mineralógica de los distintos tipos de residuos cerámicos y del resto de áridos utilizados. Los resultados muestran que es posible obtener morteros con menor densidad frente a las muestras sin contenido reciclado. Sus características los hacen idóneos para la creación de piezas prefabricadas de entrevigado para rehabilitación de forjados. Finalmente. Las piezas se usaron en un caso de estudio real, destacando las ventajas estructurales que conlleva su uso

Análisis sobre la influencia de la densidad en la termografía de infrarrojos y el alcance de esta técnica en la detección de defectos internos en la madera

This paper shows the results of a laboratory phase for the determination of the 1limits of infrared thermography in detecting internal defects in wood and, furthermore, it analyses how the density of this material can influence the surface temperature displayed in a thermogram. To this end, experimental work is carried out whereby a series of work and environmental parameters are monitored (such as environmental temperature, relative humidity, distance to target), and the process is systematized by using pieces of different wood species (different densities) and by devising a set of samples for which various possible cases are analysed in terms of size and internal position of the damage. Similarly, using these samples, a study has been conducted on the effect on the thermal image produced by an increase of humidity inside the defect phenomena normally associated with wood decay.En el presente artículo se muestran los resultados obtenidos en una fase de laboratorio al tratar de determinar el alcance de la termografía de infrarrojos en la detección de defectos internos en la madera y, por otro lado, cómo interviene la densidad de este material sobre la temperatura superficial mostrada en un termograma. Para ello se ha desarrollado un trabajo experimental donde se han controlado una serie de parámetros ambientales y de trabajo (temperatura ambiente, humedad relativa, distancia al objetivo…), y se ha sistematizado el proceso utilizando piezas de distintas especies de madera (distintas densidades) y diseñando una serie de probetas donde se han analizado varias casuísticas posibles en cuanto a tamaño y posición interna de los daños. Análogamente, sobre estas probetas se ha estudiado el efecto que produce sobre la imagen termográfica un incremento de humedad interna en el defecto asociada normalmente a los fenómenos de pudrición de la madera

Pyrolytic lignin:A promising biorefinery feedstock for the production of fuels and valuable chemicals

Lignocellulosic biomass is a key feedstock for the sustainable production of biofuels, biobased chemicals and performance materials. Biomass can be efficiently converted into pyrolysis liquids (also known as bio-oils) by the well-established fast pyrolysis technology. Currently, there is significant interest in the application of fast pyrolysis technology as principle biomass conversion technology due to its feedstock flexibility, low cost and high energy conversion efficiency, with many emerging commercial enterprises being established around the globe. Upgrading of the bio-oils is a requisite, and is complicated by its complex and heterogeneous organic nature. Pyrolysis liquids may be further separated by a simple water fractionation, yielding an aqueous sugar-rich phase and a water-insoluble pyrolytic lignin (PL) fraction. This separation step allows the use of dedicated conversion strategies for each fraction, which can be highly advantageous due to their differences in composition and reactivity. For example, the sugar-rich fractions can be used for fermentation, while the phenolic-rich PL is a particularly promising feedstock for the production of a wide range of platform chemicals and energy-dense streams upon depolymerization. To aid the emerging use of PL, novel characterization techniques and valorization strategies are being explored. In this review, the fast pyrolysis process and PL characterization efforts are discussed in detail, followed by the state-of-the-art regarding PL processing using both oxidative and reductive (catalytic) strategies, as well as a combination thereof. Possible applications are discussed and recommendations for future research are provided