In this chapter, we illustrate and discuss two distinct groups of microporous phases: the cancrinite group and the C-S-H compounds of the tobermorite and gyrolite families. The compounds in the first group present a three-dimensional purely tetrahedral framework with, apart from a single exception, Si:Al ratio equal to 1; in the mineralogical classifications they are included among feldspathoids and are generally “regarded …… distinct from zeolites, in part, at least, because of the presence of large volatile anions” (Coombs et al. 1998). The members of the second group are characterized by mixed frameworks built up by silicon (and aluminum) tetrahedra and calcium polyhedra. A common feature of both groups is the modular character of their frameworks, which are built up through various stacking ways of a single module (as in the minerals of the cancrinite-davyne family) and two or more modules as in the case of the C-S-H phases.

### Structural aspects

The minerals belonging to the cancrinite group (Merlino 1984; Deer et al. 2004) are feldspathoids with a Si:Al ratio equal to 1, with the only exception of cancrisilite, which has Si:Al = 7:5 (Khomyakov et al. 1991a,b). The available structural data for the phases with Si: Al = 1 indicate that silicon and aluminum regularly alternate in the tetrahedral sites, in accordance with the Loewenstein rule. The structural cavities host alkaline and earth-alkaline cations, and a wide variety of extra-framework anions, as well as H2O molecules. Their framework is characterized by layers containing six-membered rings of tetrahedra (Fig. 1⇓). Every ring is linked to three similar rings in the preceding layer and to three rings in the succeeding one. If the position of the rings in the first layer is called “A,” and the two possible alternative positions in the adjacent layers are “B” and …

Modular microporous minerals: cancrinite-davyne group and C-S-H phases

Potassium fertilizer via hydrothermal alteration of K-feldspar ore

The unbridled expansion of advanced agricultural and industrial facilities has led to the release of large amounts of ammonia (NH3), one of the most pernicious malodorants. Photocatalytic approache...

Photocatalytic Platforms for Removal of Ammonia from Gaseous and Aqueous Matrixes: Status and Challenges

Investigation on the formation of tobermorite in calcium silicate board and its influence factors under autoclaved curing

The New Concrete is a long-overdue survey of the rise of concrete poetry in the digital age. The accessibility of digital text and image manipulation, modern print techniques and the rise of self-publishing have invigorated a movement that first emerged in an explosion of literary creativity during the 1950s and 1960s. This new volume is a highly illustrated overview of contemporary artists and poets working at the intersection of visual art and literature, producing some of the most engaging and challenging work in either medium.

Featuring an introductory essay by renowned American poet Kenneth Goldsmith and edited by celebrated poets Victoria Bean and Chris McCabe, The New Concrete is an indispensable introduction to the breadth of concrete poetry being produced today.

Edited by Victoria Bean and Chris McCabe, with an essay by Kenneth Goldsmith

The new concrete

Tobermorite synthesis under hydrothermal conditions

The effect of amorphous and crystal sodium warfarin and its content uniformity on bioequivalence of tablets.

Overall, the tobermorite mineral crystallises under the hydrothermal conditions from the CaO-SiO2-H2O system The system of calcium hydrosilicates species is extremely complex and many factors play an important role The solubility of starting materials belongs to one of the most important factors Dissolution rates of SiO2 source are significantly affected by their particle size distribution Also the starting cation´s concentration in the aqueous solution affects the yield of the hydrothermal reaction The main aim of this contribution is to study the influence of water-to-solid ratio on tobermorite crystallization The effect of particle size of various sources of SiO2 was also studied The cost effective Ca and Si sources was primarily favoured The C/S ratio of the experiments was set to 083 All syntheses were performed at 180 °C in laboratory steel autoclaves The prepared powdered samples were characterized in order to determine the phase composition by using of X-Ray diffractometry The thermal behaviour of prepared samples was studied by TG-DTA analyser Morphology and particle size of synthetized powdered products was studied by scanning electron microscopy

The influence of starting materials´ solubility on tobermorite structure formation under the hydrothermal conditions

A method of stabilizing residual ammonia in a mixture containing energy by-products using tannin

This paper is focused on the effect of treatment of fly ash after selective non-catalytic reduction (SNCR) with tannin on autoclaved aerated concrete (AAC) production in order to reduce or stop ammonia leakage from the fresh mixture due to its alkalinity. A pure form of tannin and a tannin-based product „Farmatan“ were used as a treatment in dosage ranging from 0,5 g – 3 g of agent per 1 kg of fly ash. Efficient dosage was determined at 2 wt.% of fly ash by the speed of an indicator change due to gaseous ammonia diluted in water. The rheological properties of fresh mixtures were observed by consistency test in Viskomat showing that Farmatan causes delay of hydration. The results of bulk density and compressive strength testing revealed that Farmatan causes an increase of bulk density and at higher amount decreases the compressive strength because of thermal crack formation due to combined effect of delayed hydration and thixotropy. Using x-ray diffraction (XRD) analysis there were no differences in phase composition observed.

Lucie Galvánková

Papers

Tobermorite synthesis under hydrothermal conditions

The effect of amorphous and crystal sodium warfarin and its content uniformity on bioequivalence of tablets.

The influence of starting materials´ solubility on tobermorite structure formation under the hydrothermal conditions

A method of stabilizing residual ammonia in a mixture containing energy by-products using tannin

The Impact of Fly Ash after SNCR Treated with Tannin-Based Products on AAC Production