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2. Concrete degradation - Wikipedia

   en.wikipedia.org/wiki/Concrete_degradation

   Gypsum is easily washed away in wastewater causing a loss of concrete aggregate and exposing fresh material to acid attack. Concrete floors lying on ground that contains pyrite (iron(II) disulfide) are also at risk. As a preventive measure sewage may be pretreated to increase pH or oxidize or precipitate the sulfides in order to minimize the ...

3. Sulfate attack in concrete and mortar - Wikipedia

   en.wikipedia.org/wiki/Sulfate_attack_in_concrete...

   Oxidation of pyrite in clay formations in contact with concrete – this produces sulfuric acid which reacts with concrete. Bacterial activity in sewers – anaerobic sulfate reduction at work in the organic-rich sludges accumulated under water in the conduits produces hydrogen sulfide gas (H 2 S).

4. GFS Chemicals - Wikipedia

   en.wikipedia.org/wiki/GFS_Chemicals

   Frederick Smith was spurred to create many of the chemical compounds, especially perchlorates and trace metal perchloric acid, in response to the needs of his colleagues in analytical chemistry. [17] This tradition is continued here and is the most commonly associated part of the business when a chemist or researcher hears of GFS Chemicals.

5. Alkali–silica reaction - Wikipedia

   en.wikipedia.org/wiki/Alkali–silica_reaction

   Here, the silicic acid H 4 SiO 4, or Si(OH) 4, which is equivalent to SiO 2 · 2 H 2 O represents hydrous or amorphous silica for the sake of simplicity in aqueous chemistry. Indeed, the term silicic acid has traditionally been used as a synonym for silica, SiO 2. Strictly speaking, silica is the anhydride of orthosilicic acid, Si(OH) 4.

6. Concrete - Wikipedia

   en.wikipedia.org/wiki/Concrete

   Concrete is a composite material composed of aggregate bonded together with a fluid cement that cures to a solid over time. Concrete is the second-most-used substance in the world after water, [1] and is the most widely used building material. [2] Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminium combined. [3]

7. List of common misconceptions about science, technology, and ...

   en.wikipedia.org/wiki/List_of_common...

   Automotive batteries stored on a concrete floor do not discharge any faster than they would on other surfaces, in spite of a worry that concrete harms batteries. [511] Early batteries with porous, leaky cases may have been susceptible to moisture from floors, but for many years lead–acid car batteries have had impermeable polypropylene cases ...