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[en] Full text: The possibility of the utilization of low density polyethylene wastes by means of their modification with phenol formaldehyde oligomers (Ph FO) and PhFO with the thiourathenes has been investigation. Theology properties of the investigated systems showed that the obtained compositions can be able to be processed by the ordinary methods such as extrusion and casting
[en] A study was carried out inside the greenhouse to determine the response of lowland broccoli (Brassica oleracea) plants grown in five mixtures of coconut coir dust and peat as the growing media. The growing mixes were prepared in the following ratios (% by vol): 100% coconut coir dust, 75% coconut coir dust + 25% peat, 50% coconut coir dust + 50% peat, 25% coconut coir dust + 75% peat and 100% peat. The plants were supplied with 200 mg 1-1 nitrogen using a computerized fertigation system developed at MINT Plants grown on 100% peat exhibited reduced plant growth and yield compared to plants grown on mixes containing coconut coir dust. Plants growth and yield were increased on growing media contained > 50% coconut coir dust; however, the highest total plant dry weight, plant height and yield were obtained from plants grown on 100% coconut coir dust. Total nitrogen concentration in the leaves and stems was not significantly different in all mixture of the growing media regardless of whether coconut coir dust or peat was used. In general, nitrate -nitrogen concentrations were lowest in the floret than in the leaves and stem tissues of plants grown on all growing media used in the study. However, nitrate-nitrogen concentrations in the leaves, stems and florets were lowest in the plants grown on 100% peat compared to the plants grown on growing media containing coconut coir dust. The concentrations of nitrate-nitrogen in the florets, which ranged from 290 to 450 mg N kg-l/dry weight, are considered to be under permissible levels by European standards. (Author)
[en] This work proposes an effective solution for the recycling of coffee waste by incorporating it (10, 20 and 30wt.%) as a secondary material with clay (Cretaceous deposit of Moroccan Meseta) to produce porous lightweight ceramics (class BIII) whose quality is similar to that of ceramic materials with insulating character. The applied raw materials were characterized in terms of their composition (XRD, XRF, IR), microstructural analysis (polarized microscope) and thermal behavior (TDA/TGA). The ceramic materials resulted after firing at 1150°C, were investigated regarding the phases composition, structural characteristics and physical properties of technological interest. In fact, the thermal treatment at 1150°C gives samples having the following technological characteristics: P=42.81%, d=1.46g/cm3, λ=0.39W/mK, WA=29.25% and F.S=10.75MPa. The combination of XRD and polarized microscope, allowed a better analysis of the mineralogical and structural evolution after sintering at 1150°C.
[es]Este trabajo propone una solución efectiva para el reciclaje de residuos de café incorporándolo (10, 20 y 30% .wt) como material secundario con arcilla (depósito cretácico de la Meseta marroquí) para producir cerámicas ligeras porosas (clase BIII) cuya calidad es similar a la de los materiales cerámicos con carácter aislante. Las materias primas aplicadas se caracterizaron en términos de su composición (XRD, XRF, IR), análisis microestructural (microscopio polarizado) y comportamiento térmico (TDA / TGA). Los materiales cerámicos obtenidos después de la cocción a 1150 ° C, fueron investigados sobre la composición de las fases, las características estructurales y las propiedades físicas de interés tecnológico. De hecho, el tratamiento térmico a 1150 ° C da muestras que tienen las siguientes características tecnológicas: P = 42.81%, d = 1.46 g / cm3, λ = 0.39 W / m × K, WA = 29.25% y F.S = 10.75 MPa. La combinación de XRD y microscopio polarizado permitió un mejor análisis de la evolución mineralógica y estructural después de la sinterización a 1150 ° C.
[en] A number of environmental and energy technologies have benefited substantially from nano-scale technology: reduced waste and improved energy efficiency; environmentally friendly composite structures; waste remediation; energy conversion. In this report examples of current achievements and paradigm shifts are presented: from discovery to application; a nano structured materials; nanoparticles in the environment (plasma chemical preparation); nano-porous polymers and their applications in water purification; photo catalytic fluid purification; hierarchical self-assembled nano-structures for adsorption of heavy metals, etc. Several themes should be considered priorities in developing nano-scale processes related to environmental management: 1. To develop understanding and control of relevant processes, including protein precipitation and crystallisation, desorption of pollutants, stability of colloidal dispersion, micelle aggregation, microbe mobility, formation and mobility of nanoparticles, and tissue-nanoparticle interaction. Emphasis should be given to processes at phase boundaries (solid-liquid, solid-gas, liquid-gas) that involve mineral and organic soil components, aerosols, biomolecules (cells, microbes), bio tissues, derived components such as bio films and membranes, and anthropogenic additions (e.g. trace and heavy metals); 2. To carry out interdisciplinary research that initiates Noel approaches and adopts new methods for characterising surfaces and modelling complex systems to problems at interfaces and other nano-structures in the natural environment, including those involving biological or living systems. New technological advances such as optical traps, laser tweezers, and synchrotrons are extending examination of molecular and nano-scale processes to the single-molecule or single-cell level; 3. To integrate understanding of the roles of molecular and nano-scale phenomena and behaviour at the meso- and/or macro-scale over a period of time. Environmental compartments for investigations are not limited and might include terrestrial locations (e.g. acid mines), aquifers, polar environments, or the atmosphere. (author)
[en] In this report the waste management and material recycling in Finland and in other countries has been viewed as an overall situation. The survey is based on expert interviews, the literature in this field and on international conferences and exhibitions. Some of the material has been gathered from earlier reports made by VTT and Neopoli
[en] Radon exhalation rates from five studied laboratory waste samples resulted from five different sedimentary rock types named sandy dolostons, siltstone-two samples-, marly clay stone and black shale were measured using ‘‘Sealed Can technique”. These rates were found to vary between 0.005 and 0.015 Bq m2 h-1. A positive correlation was found between the radon exhalation rates and the radium activities. The emanation coefficients were calculated for these laboratory waste samples which varied between 0.0004 and 0.0007 according to the physical and chemical characterize of the wastes. These results are partially in accordance with autonite acid leached tailings on laboratory scale (USA). These results led us to pay attention about the effect and impact of these wastes on the environment
[en] Short paper describing the recovery of uranium from gold mining tailings. Twenty seven mines are concerned and seventeen plants ensure the treatment. In 1979, 4797 tonnes of uranium mineral was recovered. Brief technical indications are given on the sorting installations
[fr]Courte monographie decrivant la recuperation de l'uranium faite a partir des steriles de mines d'or. Vingt-sept mines sont concernees et dix sept usines assurent le traitement. En 1979, on a recupere 4797 t d'uranium mineral. On donne de breves indications techniques sur les installations de recuperation
[en] Application of recycling material resources in production processes instead of natural mineral raw materials and fuel may be one of the levers of reduction of the materials inputs and increase of production profitability under new economic conditions. Karaganda coal preparation there are annually developed 800-859 thousand tonnes of the coal slimes (with moisture content 30-50 %) being removed to the slime tanks where its are already accumulated in the extent of 10 million tonnes. The experimental tests have shown that specially prepared and dewatered up to 8-10 % coal slime can be used as an alternative to power-generating fuel. It has following performances: the size fraction is 0-0.3 mm, the low heat value - 400 kcal/kg, the ash content 38-40 %, the volatile matter - 28 %. Specification of preparation coal slime for burning process have been developed
[en] The United States Government currently has an abundance of depleted uranium (DU). This surplus of about 1 billion pounds is the result of an enrichment process using gaseous diffusion to produce enriched and depleted uranium. The enriched uranium has been used primarily for either nuclear weapons for the military or nuclear fuel for the commercial power industry. Most of the depleted uranium remains at the enrichment process plants in the form of depleted uranium hexafluoride (DUF6). The Department of Energy (DOE) recently began a study to identify possible commercial applications for the surplus material. One of these potential applications is to use the DU in high-density strikers/hammers in pneumatically driven tools, such as jack hammers and piledrivers to improve their impulse performance. The use of DU could potentially increase tunneling velocity and excavation into target materials with improved efficiency. This report describes the efforts undertaken to analyze the particulars of using DU in two specific striking applications: the jackhammer and chipper tool