A5082669417- Concrete and Cement Materials Research
- Calcium Carbonate Crystallization and Inhibition
- CO2 Sequestration and Geologic Interactions
- Building materials and conservation
- Magnesium Oxide Properties and Applications
- Concrete Corrosion and Durability
- Glass properties and applications
- Chemical Synthesis and Characterization
- Innovative concrete reinforcement materials
- Bone Tissue Engineering Materials
- Clay minerals and soil interactions
- Innovations in Concrete and Construction Materials
- Concrete Properties and Behavior
- Minerals Flotation and Separation Techniques
- Zeolite Catalysis and Synthesis
- Paleontology and Stratigraphy of Fossils
- Diatoms and Algae Research
- Analytical Chemistry and Sensors
- Acoustic Wave Resonator Technologies
- Electrophoretic Deposition in Materials Science
Construction Solutions (United States)
2009
Abstract Since its widespread use in concrete began over 100 years ago, the chemical composition and physical properties of portland cement have changed only incrementally response to various competing pressures constructability cost. Instead, construction demands been met largely through development introduction admixtures that are added binder during mixing. These same persist into 21 st Century just as important now before, yet newer driving forces simultaneously pushing industry both...
Calcium silicate hydrate (C-S-H) is the binder in concrete, most used synthetic material world. The main weakness of concrete lack elasticity and poor flexural strength considerably limiting its potential, making reinforcing steel constructions necessary. Although properties C-S-H could be significantly improved organic hybrids, full potential this approach not reached because random nanoplatelet structure. Taking inspiration from a sea urchin spine with highly ordered nanoparticles...
Despite a millennial history and the ubiquitous presence of cement in everyday life, molecular processes underlying its hydration behavior, like formation calcium–silicate–hydrate (C–S–H), binding phase concrete, are mostly unexplored. Using time-resolved potentiometry turbidimetry combined with dynamic light scattering, small-angle X-ray cryo-TEM, we demonstrate C–S–H to proceed via complex two-step pathway. In first step, amorphous dispersed spheroids formed, whose composition is depleted...
Nanotechnology enables the design of materials with outstanding performance. A key element nanotechnology is ability to manipulate and control matter on nanoscale achieve a certain desired set specific properties. Here, we discuss recent insight into formation mechanisms inorganic nanoparticles during precipitation reactions. We focus calcium carbonate, describe various transient stages potentially occurring way from dissolved constituent ions finally stable macrocrystals-including solute...
AbstractThe most important phase in Portland cement is tricalcium silicate, which leads during its hydration to the nucleation and growth of calcium silicate hydrate [referred as C–S–H, (CaO)x–SiO2–(H2O)y]. The development this around grains responsible for setting hardening pastes. general term designating cements alite. This name relates all polymorphs containing various foreign ions inserted their structure. These may influence intrinsic reactivity, once released dissolution, they...
We present an in-depth study of the formation stable suspensions low density aggregates calcium silicate hydrate (C–S–H) particles stabilized by comb-like copolymers. These exhibit fundamentally interesting properties such as gel at 1.4 vol% particles. Furthermore, they constitute a novel class hardening accelerators for cementitious systems. Stabilization C–S–H polyelectrolytes is essential synthesis and active suspensions. Comb-polymers consisting charged monomers (acrylic acid or...
The surface topography that develops during the dissolution of alite (or C 3 S) has never been considered as an important aspect hydration portland cement. Like many other minerals, results in formation etch pits. In this study, a simple model with handful parameters is proposed to explore kinetic consequences pitting on alite. first consequence accelerating period which reactive surface, is, pit, expands. This new feature, authors’ opinion reported previously for alite, supported by...
Recent advances in bridging kinetics and thermodynamics of mineral dissolution have opened new horizons our understanding the role cement hydration. Indeed most hydration kinetic regimes alite can be rationally envisioned from a perspective. This short note reviews some key findings on mechanisms their implication for cementitious systems.
Phage display experiments on industrially important calcium silicate hydrates (C-S-H), the main hydration product of ordinary Portland cement, suggest fundamentally different specific binding motifs compared to hitherto existing commercial cement additives. According that, a strong and adsorbing additive C-S-H should have three features which are negative charge, H-bond formers (especially amide functions) hydrophobic part.
The seeding effect of finely dispersed calcium silicate hydrate (C-S-H) particles on tricalcium hydration and cement was investigated. An extremely small amount C-S-H nuclei (0.3%) significantly increases the degree both by promoting growth clusters into pore solution instead around or grains. Indeed, it clearly shown that takes place delivered materials therefore in spaces. Nevertheless, some persist onto efficiency seed suspensions for accelerating is qualitatively related to cluster size...
Load-bearing reinforcing elements in a continuous matrix allow for improved mechanical properties and can reduce the weight of structural composites. As performance composite systems are heavily affected by interfacial properties, tailoring interactions between matrices is crucial problem. Recently, several studies using bio-inspired model suggested that interlocking an efficient mechanism energy dissipation platelet-reinforced While cheap effective solutions available at macroscale,...
The naturally occurring mineral 11 Å tobermorite is an important calcium silicate hydrate phase often used as a model structure for the poorly ordered (C-S-H) present in hydrated cement. In this work we hydrothermal synthesis of highly crystalline anomalous by conventional and microwave treatment. assisted provides faster access to material terms reaction time, while method yields samples with higher crystallinity. For borosilicate glass was Si precursor, which proves be excellent starting...
Abstract The atomic structure of calcium-silicate-hydrate (C 1.67 –S–H x ) has been studied. Atomistic C–S–H models suggested in our previous study have revised order to perform a direct comparison energetic stability the different structures. An extensive set periodic structures with variation water content was created, and then optimized using molecular dynamics reactive force field ReaxFF quantum chemical semiempirical method PM6. All show organization molecules inside C–S–H. new...
Abstract Nanotechnologie ermöglicht die Herstellung von Materialien mit hervorragenden Leistungscharakteristika. Ein Schlüsselelement der ist Fähigkeit, Materie auf Nanoskala zu manipulieren und steuern, um einen gewünschten Mix aus spezifischen Eigenschaften erhalten. Hier stellen wir jüngste Erkenntnisse den Bildungsmechanismen anorganischen Nanopartikeln im Rahmen Fällungsreaktionen vor. Am Beispiel Calciumcarbonat beschreiben verschiedenen Zwischenstufen, dem Weg gelösten Ionen bis...