Search results
Results from the WOW.Com Content Network
Sodium metasilicate is the chemical substance with formula Na 2 SiO 3, which is the main component of commercial sodium silicate solutions. It is an ionic compound consisting of sodium cations Na + and the polymeric metasilicate anions [– SiO 2− 3 –] n.
Sodium silicate solutions can also be used as a spin-on adhesive layer to bond glass to glass [21] or a silicon dioxide–covered silicon wafer to one another. [22] Sodium silicate glass-to-glass bonding has the advantage that it is a low-temperature bonding technique, as opposed to fusion bonding. [21]
Idealized structure of sodium metasilicate. Metasilicates are silicates containing ions of empirical formula SiO 2− 3. Common stoichiometries include M I 2 SiO 3 and M II SiO 3. Metasilicates can be cyclic, usually the hexamer (SiO 3) 12− 6 or chains (SiO 3)n 2−. [1] Common compounds containing metasilicate anion are: Inosilicates
Antibiotic resistance tests: Bacteria are streaked on dishes with white disks, each impregnated with a different antibiotic. Clear rings, such as those on the left, show that bacteria have not grown—indicating that these bacteria are not resistant. The bacteria on the right are fully resistant to all but two of the seven antibiotics tested. [33]
The standard can be compared visually to a suspension of bacteria in sterile saline or nutrient broth. If the bacterial suspension is too turbid, it can be diluted with more diluent. If the suspension is not turbid enough, more bacteria can be added. McFarland nephelometer standards:{2}
Sodium orthosilicate is the chemical compound with the molecular formula Na 4 SiO 4. It is one of the sodium silicates, specifically an orthosilicate, formally a salt of the unstable orthosilicic acid H 4 SiO 4. [2] [3] [4]
Depiction of a metasilicate chain, emphasizing the tetrahedral silicate subunits. Alternative depiction of a metasilicate chain emphasizing the Si-O bonds. With two shared oxides bound to each silicon, cyclic or polymeric structures can result. The cyclic metasilicate ring Si 6 O 12− 18 is a hexamer of SiO 3 2-.
Upon removal of the bacteriostat, the bacteria usually start to grow rapidly. This is in contrast to bactericides, which kill bacteria. [1] Bacteriostats are often used in plastics to prevent growth of bacteria on surfaces. Bacteriostats commonly used in laboratory work include sodium azide (which is acutely toxic) and thiomersal. [citation needed]