Effect Of Wood Particle Treatment On The Properties Of Gypsum Plaster Pastes And Composites

In this work the performance of gypsum plaster and wood particle in pastes and composites was investigated. Wood particles of fineness 0.42 mm and 1.20 mm were employed. Natural wood particles and the treated ones in cold or hot water (80 degrees C) were performed. The effects of the extractives solutions from the treatments applied to the wood particles on wood-gypsum compatibility were studied. For pastes and composites, waterto-gypsum ratio was 0.65. Wood particles-to-gypsum plaster ratios were 5%, 10% and 15%, in mass. Kinetics of temperature, mechanical performance and dynamic elasticity modulus by ultrasound measurements were applied to evaluate the gypsum plaster pastes and its composites behaviors. Results show that the extractive solutions changed the time of gypsum plaster hydration, being more sensitive to hot water treatment. The composites compressive strength increase with the wood particles pretreatment. The best result was to room temperature treatment. The same performance was found to the modulus of elasticity. Treatments have improved significantly the flexural strength. The best wood particle content was 10%. These results show the possibility of using this wood waste with an easy and simple treatment to make eco-efficient building materials.2141032104

EFFECTS OF THERMAL TREATMENT ON THE PHYSICOCHEMICAL CHARACTERISTICS OF GIANT BAMBOO

Despite countless use possibilities for bamboo, this material has two major disadvantages. One drawback is the low natural durability of most bamboo species due to presence of starch in their parenchyma cells. The other equally important drawback is the tendency bamboo has to present dimensional variations if subjected to environmental change conditions. In an attempt to minimize these inconveniences, strips (laths) of Dendrocalamus giganteus Munro were taken from different portions of the culm and subjected to several temperatures, namely 140 degrees C, 180 degrees C, 220 degrees C, 260 degrees C and 300 degrees C under laboratory conditions, at the ESALQ-USP college of agriculture. The thermal treatment process was conducted in noninert and inert atmospheres (with nitrogen), depending on temperature Specimens were then subjected to physicomechanical characterization tests in order to determine optimum thermal treatment conditions in which to preserve to the extent possible the original bamboo properties. Results revealed that there is an optimum temperature range, between 140 degrees and 220 degrees C, whereby thermally treated bamboo does not significantly lose its mechanical properties while at the same time showing greater dimensional stability in the presence of moisture.17336136

Effect of wood particle treatment on the properties of gypsum plaster pastes and composites

In this work the performance of gypsum plaster and wood particle in pastes and composites was investigated. Wood particles of fineness 0.42 mm and 1.20 mm were employed. Natural wood particles and the treated ones in cold or hot water (80 °C) were performed. The effects of the extractives solutions from the treatments applied to the wood particles on wood-gypsum compatibility were studied. For pastes and composites, water-to-gypsum ratio was 0.65. Wood particles-to-gypsum plaster ratios were 5%, 10% and 15%, in mass. Kinetics of temperature, mechanical performance and dynamic elasticity modulus by ultrasound measurements were applied to evaluate the gypsum plaster pastes and its composites behaviors. Results show that the extractive solutions changed the time of gypsum plaster hydration, being more sensitive to hot water treatment. The composites compressive strength increase with the wood particles pretreatment. The best result was to room temperature treatment. The same performance was found to the modulus of elasticity. Treatments have improved significantly the flexural strength. The best wood particle content was 10%. These results show the possibility of using this wood waste with an easy and simple treatment to make eco-efficient building materials.2141032104

Método De Preparação De Materiais Lignocelulósicos Para Análise Macroscópica

Método de preparação de materiais lignocelulósicos para análise macroscópica, do tipo que pode ser empregado para a preparação de amostras tais como madeira e similares e que compreender três etapas básicas, sendo que, a primeira etapa consiste no corte e polimento mecânico das amostras; a segunda etapa compreende a digitalização, tratamento e caracterização das imagens obtidas; e a terceira etapa consiste na aplicação das informações obtidas a partir das imagens digitalizadas e tratadas da segunda etapa.BR9905465 (A)D21B1/00D21B1/00BR19999905465D21B1/00D21B1/0

Bambu: Matéria-prima para o Século XXI

Apresentação feita pelo Professor Beraldo durante o ENSUS 201

Processo De Obtenção De Compositos Biomassa Vegetal E Aglomerantes Inorgânicos Para Construção E Produto Assim Obtido

A presente invenção se refere a um processo de obtenção de um compósito biomassa vegetal e aglomerantes inorgânicos para ser usado como material de construção. Mais especificamente, o processo consiste das seguintes etapas: a) pré-tratamento da biomassa vegetal, composta de resíduos de exploração agro-industrial, em água, durante 0 a 3 horas A uma temperatura que varia entre 20 e 90oC; b) tratamento de impermeabilização da biomassa vegetal através da pulverização de soluções à base de cimento, betume e sais inorgânicos, com deposição de resíduos sólidos de 0 a 10% em relação a massa das partículas; c) dissolução na água de amassamento de 0 a 4% de produto acelerador da pega (cloretos, sulfatos, silicatos), em relação à massa de aglomerante. O produto é obtido através da mistura manual ou mecânica de 1 parte de aglomerante, (cimento ou substituído de 0-60% oir gessom oak iy calcário agrícola) de 1 a 5 partes de agregado mineral miúdo, de 1 a 6 partes de biomassa vegetal tratada e de 0,5 a 2 partes da solução aquosa (dosagens volumétricas) e por esta mistura ser depositada em formas e submetida à vibração manual ou mecânica por 0 a 10 minutos), sendo o material desformado, curado de 0 a 60 minutos em reator fechado dispondo de CO2, recoberto por lona plástica durante 0 a 24 horas e submetido de 0 a 5 ciclos de umidificação e secagem durante 0 a 28 dias.BR9504705 (A)C04B18/24C04B18/24BR19959504705C04B18/24C04B18/2

Optimization of Ni-Based WC/Co/Cr Composite Coatings Produced by Multilayer Laser Cladding

As a surface coating technique, laser cladding (LC) has been developed for improving wear, corrosion, and fatigue properties of mechanical components. The main advantage of this process is the capability of introducing hard particles such as SiC, TiC, and WC as reinforcements in the metallic matrix such as Ni-based alloy, Co-based alloy, and Fe-based alloy to form ceramic-metal composite coatings, which have very high hardness and good wear resistance. In this paper, Ni-based alloy (Colmonoy 227-F) and Tungsten Carbides/Cobalt/Chromium (WC/Co/Cr) composite coatings were fabricated by the multilayer laser cladding technique (MLC). An optimization procedure was implemented to obtain the combination of process parameters that minimizes the porosity and produces good adhesion to a stainless steel substrate. The optimization procedure was worked out with a mathematical model that was supported by an experimental analysis, which studied the shape of the clad track generated by melting coaxially fed powders with a laser. Microstructural and microhardness analysis completed the set of test performed on the coatings

Lower urinary tract symptoms and benign prostatic hyperplasia and their impact on quality of life

LUTS is an acronym that refers to symptoms affecting the lower urinary tract, which are very common in elderly subjects (between 60 and 70%), and often associated with, but not always caused by, benign prostatic hypertrophy (BPH). BPH is a chronic condition characterized by an increase in the number of cells, particularly in the transition area of the prostate. BPH involves a compression of the surrounding tissues, consequently obstructing vescical voiding. Nycturia and urgency represent the most prevalent symptoms and those with the greatest impact on quality of life measured as urinary-specific health-related quality. The prevalence of BPH is directly proportional to age; therefore, the absolute number of subjects affected is growing throughout the world. BPH is one of the most common medical conditions affecting those over 50. The overall cost for the diagnosis and treatment of BPH-related LUTS, in the US, has been estimated at approximately 1.1 billion US$/year, compared to total annual expenditure for urological conditions of some 9 billion and this cost continues to increase. The quick prostate test, which was developed by the Italian Urology Society (SIU), is an easy to use instrument that can be utilized in first-level screening for evaluation of the male population with LUTS. This test can be used both in patients not on pharmacological treatment and as a therapy-monitoring instrument. A positive response to one of the questions is sufficient for requesting a more in-depth investigation, which may provide indications on the therapeutic strategy to be taken