J. Appl. Cryst.の発刊に際して

The hydrothermal synthesis of zeolites: precursors, intermediates and reaction mechanism

Composites have been found to be the most promising and discerning material available in this century. Presently, composites reinforced with fibers of synthetic or natural materials are gaining more importance as demands for lightweight materials with high strength for specific applications are growing in the market. Fiber-reinforced polymer composite offers not only high strength to weight ratio, but also reveals exceptional properties such as high durability; stiffness; damping property; flexural strength; and resistance to corrosion, wear, impact, and fire. These wide ranges of diverse features have led composite materials to find applications in mechanical, construction, aerospace, automobile, biomedical, marine, and many other manufacturing industries. Performance of composite materials predominantly depends on their constituent elements and manufacturing techniques, therefore, functional properties of various fibers available worldwide, their classifications, and the manufacturing techniques used to fabricate the composite materials need to be studied in order to figure out the optimized characteristic of the material for the desired application. An overview of a diverse range of fibers, their properties, functionality, classification, and various fiber composite manufacturing techniques is presented to discover the optimized fiber-reinforced composite material for significant applications. Their exceptional performance in the numerous fields of applications have made fiber-reinforced composite materials a promising alternative over solitary metals or alloys.

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Fiber-Reinforced Polymer Composites: Manufacturing, Properties, and Applications.

Porous Materials Water in Porous Materials Flow in Porous Materials Unsaturated Flows Unsaturated Flow in Building Physics Composite Materials Evaporation and Drying Topics in Water Transport Appendices Symbols Used Properties of Water Minerals, Salts and Solutions Other Liquids Other Data

Water Transport in Brick, Stone and Concrete

Two-dimensional MXenes: From morphological to optical, electric, and magnetic properties and applications

Thermally treated clay sediments as geopolymer source material

This research has investigated the properties of thermally insulating geopolymer composites that were prepared using waste expanded polystyrene as lightweight aggregate. The geopolymer matrix was synthetized using metakaolin and an alkaline activating solution. To improve its mechanical properties, this matrix was modified by the addition of an epoxy resin to form an organic-inorganic composite. Moreover, in order to reduce drying shrinkage marble powder was used as an inert filler. The materials obtained were characterized in terms of physico-mechanical properties, thermal performance and microstructure. The geopolymer expanded polystyrene composite have improved properties compared to Portland cement-based materials, with higher strengths and lower thermal conductivity. The research demonstrates the manufacture of sustainable lightweight thermally insulating geopolymer composites using waste expanded polystyrene.

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Mechanical and thermal properties of lightweight geopolymer composites

Novel hybrid organic-geopolymer materials

Nowadays fiber reinforced polymers represent a well-established technique for structural retrofit of reinforced concrete structural members. However, the severe degradation of mechanical properties with temperature and fire conditions represents one of the weakest point of these systems. The use of a fire resistant inorganic resin, as geopolymers, instead of polymeric resins, would be highly desirable to overcome this issue. The present work is aimed at investigating the effectiveness of two different fiber reinforced geopolymer-based systems in strengthening of reinforced concrete beams. In particular, this paper presents the main outcomes of experimental flexural tests on shallow reinforced concrete beams strengthened with high strength steel cord and carbon fiber reinforced geopolymers, cured at room temperature. No mechanical anchorage was employed to fix the composite to the concrete substrate. The mechanical behavior of the strengthened beams was evaluated by means of four-points bending tests. Two beam specimens for each system (i.e. steel cord and carbon fiber reinforcement) and one unstrengthened control beam were tested. A significant increase in the failure strength of the reinforced concrete beams was experienced, in case of steel cord reinforcement. The adhesion of geopolymer to the concrete substrate and to steel cords and carbon fibers was also evaluated by means of scanning electron microscopy.

Use of geopolymers for composite external reinforcement of RC members

In this work, three samples of municipal solid waste incinerators fly ash (MSWI-FA) have been stabilized in systems containing coal fly ash to create geopolymers through a polycondensation reaction. Monolithic products have been obtained with both MSWI fly ash as received and after the partial removal of chloride and sulfate by water washing. The polycondensation products have been characterized qualitatively by means of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy and quantitatively, through the determination of the volume of reacted water and silicate. Furthermore, the heavy metals and chloride releases together with the physico-mechanical properties have been evaluated on the hardened products. In conclusion, considering the technological and environmental performances of the obtained geopolymers, they could be suitable for many non-structural applications, such as backfilling of abandoned quarries, decorative materials or brick fireplaces, hearths, patios, etc.

Claudio Ferone

Papers

Thermally treated clay sediments as geopolymer source material

Mechanical and thermal properties of lightweight geopolymer composites

Novel hybrid organic-geopolymer materials

Use of geopolymers for composite external reinforcement of RC members

Recycling of Pre-Washed Municipal Solid Waste Incinerator Fly Ash in the Manufacturing of Low Temperature Setting Geopolymer Materials