in parts of desert regions in our country, groundwater is the only source of fresh water and due to geological formation, the concentration of hexavalent chromium in groundwater will reach beyond the allowed limits. furthermore, previous studies showed that hexavalent chromium is a cancerous substance for humans and toxic for other organisms. in this study the removal of hexavalent chromium fro...

Cement-based cementitious materials present an alkaline environment and mainly exist in the form of Ca(OH)2. Phosphogypsum, as a retarder materials, is often added to cement instead gypsum, fluorine by-product phosphogypsum also fixed CaF2. These cement-based serve environments containing carbonate groundwater, which changes stability solidified This paper studied solid liquid Ca(OH)2-CaF2, Ca(...

Lotharmeyerite, calcium bis-(zinc/manganese) bis-(arsenate) bis-(hydroxide/hydrate), Ca(Zn,Mn(3+))(2)(AsO(4))(2)(H(2)O,OH)(2), is a member of the natrochalcite group of minerals, which are characterized by the general formula AM(2)(XO(4))(2)(H(2)O,OH)(2), where A may be occupied by Pb(2+), Ca(2+), Na(+), and Bi(3+), M by Fe(3+), Mn(3+), Cu(2+), Zn(2+), Co(2+), Ni(2+), Al(3+), and Mg(2+), and X ...

An innovative material constituted of a natural biopolymers blend (Funori) from Gloiopeltis algae and Ca(OH)2 nanocrystals was developed to consolidate linen fibers for cultural heritage conservation preventing future degradation due the alkaline reservoir by Ca(OH)2. The procedure extract Funori reliable reproducible consolidation performances aged Funori/Ca(OH)2 smart system were showed highl...

OBJECTIVE Calcium hydroxide (Ca(OH)2) has been used in endodontics as an intracanal medicament due to its antimicrobial effects and its ability to inactivate bacterial endotoxin. The inability to totally remove this intracanal medicament from the root canal system, however, may interfere with the setting of eugenol-based sealers or inhibit bonding of resin to dentin, thus presenting clinical ch...

BACKGROUND The purpose of this study was to use micro-computed tomography (micro-CT) scanning to evaluate the efficacy of sonic and passive ultrasonic irrigation (PUI) on calcium hydroxide (Ca[OH](2)) removal and to measure the volume and percentage of Ca(OH)(2) remaining in the root canal system. METHODOLOGY The root canals of 46 extracted human mandibular molar teeth were prepared with rota...