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Calcium sulfate or calcium sulphate is the inorganic compound with the formula CaSO 4 and related the form of γ anhydrite the anhydrous form it is used as a particular hydrate is better known as plaster of Paris and another occurs naturally as the mineral has many uses in industry All forms are white solids that are poorly soluble in water
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Focussing on PJIs there is a paucity of robust data in the literature Table 2 Combinations of cement spacer and calcium sulfate/phosphate carrier of antibiotics showed significantly lower recurrence rate p < in the group receiving the carrier % compared to the group with cement spacer alone % [17]
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While the influence of the source and amount of calcium sulfate on hydration has been widely studied in ye elimite rich calcium sulfoaluminate cements [10 14 15 16 29 30 31] only a limited number of studies have focused on belite calcium sulfoaluminate cements in which belite is the most abundant phase in the Juenger [] investigated clinkers with a differing content of
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Functions A common industrial chemical known for its ability to trap moisture This substance is most often used as a coagulant and desiccant a substance that induces a state of dryness Because this ingredient serves as the main component to materials such as drywall plaster and cement it plays a vital role in the construction industry
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As a raw material it can be used in the production of CSA cement slag gypsum cement gypsum bauxite expansive cement etc 2 As a mineralizer it can reduce the calcining temperature and save coals 3 As a cement retarder it makes the cement setting time in line with national standards and user requirements by its retarding effect 4
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Tricalcium aluminate C3A is one of the main constituents of Portland cement Even though it represents less than 10% of the total composition its strong reaction with water can lead to a rapid setting called flash set Gypsum is added to regulate this reaction and preserves the workability of the cement paste at early ages
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In the cement system the presence of ettringite depends on the ratio of calcium sulfate to tri calcium aluminate C 3 A when this ratio is low ettringite forms during early hydration and then converts to the calcium aluminate monosulfate AFm phase or Al 2 O 3 Fe 2 O 3 mono
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ettringite and gypsum due to the activation effect of alkali and sulfate in alite barium calcium sulphoaluminate cement and the suitable mass fraction of slag was 20% The corrosion resistant
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By the inclusion of nano SiO 2 a more compact and refinement of air void structure of lightweight aggregate concrete was obtained [45] This paper presented the experimental study conducted to find out the effect of nano SiO 2 in concrete under sulfate attack Cement was substituted by nano silica with 2 4 6 and 8% by weight
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High performance concrete HPC is a new type of concrete with the advantages of high durability high strength and high working performance which is widely used in highway tunnels underground passages and coastal constructions [1 2 3] In such a harsh environment the HPC structures are continuously exposed to sulfate attack which is well known to damage the physical and mechanical
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Cement augmentation of pedicle screws is one of the most promising approaches to enhance the anchoring of screws in the osteoporotic spine To date there is no ideal cement for pedicle screw augmentation The purpose of this study was to investigate whether an injectable bioactive and degradable calcium sulfate/hydroxyapatite CaS/HA cement could increase the maximum pull out force of
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The function of cement based calcium sulfate is to increase the initial cement setting period 7 Sulfur Trioxide SO3 Through steel arsenic and sulfur trioxide is about 1 to 3% Their role is to make the sound of concrete The cement is unsound when it is in large volume 8 Alkalis
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Calcium Sulfate Chemical formula is CaSO 4 This is present in cement in the form of gypsum CaSO 4 2H 2 O It slows down or retards the setting action of cement Sulfur Trioxide Chemical formula is SO 3 It should not be present for more than 2% Excess Sulfur Trioxide causes the cement to unsound Alkaline It should not be present more than 1%
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PDF Cement augmentation of pedicle screws is one of the most promising approaches to enhance the anchoring of screws in the osteoporotic spine Find read and cite all the research you
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Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate with the chemical formula CaSO 4 ·2H 2 O It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster blackboard or sidewalk chalk and drywall Alabaster a fine grained white or lightly tinted variety of gypsum has been used for sculpture by many cultures including Ancient Egypt
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Osteoporosis is a growing public health concern worldwide To avoid extra surgeries developing biodegradable bone cement is critical for the treatment of osteoporosis Herein we designed calcium phosphate/calcium sulfate cement reinforced with sodium carboxymethyl cellulose CMC/OPC It presents an appropriate p
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The role of gypsum in cement PDF Cement Concrete The role of gypsum in cement View presentation slides online Scribd is the world s largest social reading and publishing site Open navigation menu Close suggestionsSearchSearch enChange Language close menu Language English selected Español Português Deutsch Français Русский Italiano Română
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Supersulfated cements SSC are binders comprising mostly of granulated blast furnace slag GBFS generally higher than 80% calcium sulfate 10 20% and small quantities of activator which can be Portland cement or clinker or even other alkaline activators such as lime or potassium hydroxide
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Sodium sulfate reacts with calcium aluminate hydrate and calcium hydroxide leading to the formation of ettringite and gypsum which is the degradation mechanisms of OPC in sodium sulfate solution However it is evident that the hydration products of CSA cement are ettringite C S H and amorphous AH3
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Gypsum is a mineral and is hydrated calcium sulphate in chemical form Gypsum plays a very important role in controlling the rate of hardening of the cement so its is generally termed as retarding agent of cement It is mainly used for regulating the setting time of cement and is an indispensable component
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Reduced Resistance to Sulphate Attack Sulphates can react with calcium and aluminum ions resulting in the formation of substances that disrupt the concrete These include calcium sulfate and calcium sulphoaluminate hydrates Calcium chloride can reduce resistance to this process Effects of Calcium Chloride on Concrete
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The Role of Calcium Carbonate in Cement Hydration Limestone mainly consisting of calcite is a permitted additive to Portland cements often up to a 5 wt % limit It is shown by experiment and calculation that much if not all of this calcite is reactive and affects the distribution of lime alumina and sulfate and thereby alters the
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Answer 1 of 2 Dicalcium Silicate C2S hardens slowly and contributes largely to strength increases at ages beyond 7 days There are three main crystal forms of C2S α β but the β form is the only one occurred in the Portland cement and it react slowly with water its reaction is
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the manufacture of calcium sulfoaluminate csa cements is csa cements are prepared by mixing the clinker with different more environmentally friendly than that of opc [1 4] as their pro amounts of a calcium sulfate set regulator such as gypsum csh2 duction releases up to 40% less co2 than the latter this reduction bassanite or …
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Calcium hydroxide released during the hydration of the calcium silicates is also vulnerable to attack Because cement liberates heat when it hydrates concrete placed in large masses as in dams can cause the temperature inside the mass to rise as much as 40 °C 70 °F above the outside temperature Subsequent cooling can be a cause of cracking
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Otherwise ettringite 3CaO·Al2O3·3CaSO 4 ·32H 2 O the cement bacillus will form and cause their destruction In portland cement based products the sulfate from gypsum reacts with calcium aluminates from the portland cement early in their lives and forms needle like micro crystals of ettringite
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Gypsum is a mineral and is hydrated calcium sulphate in chemical form Gypsum plays a very important role in controlling the rate of hardening of the cement so its is generally termed as
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Reading time 2 minutes Sulphate Resisting Cement is a type of Portland Cement in which the amount of tricalcium aluminate C3A is restricted to lower than 5% and 2C 3A C4AF lower than 25% which reduces the formation of sulphate salts The reduction of sulphate salts lowers the possibility of sulphate attack on the concrete
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calcium sulfate cement A cement that depends primarily on the hydration of calcium sulfate for its setting and hardening properties includes Keene s cement Parian cement plaster of paris McGraw Hill Dictionary of Architecture and Construction Copyright © 2024 by McGraw Hill Companies Inc Want to thank TFD for its existence
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Strength promoting mechanism of alkanolamines on limestone calcined clay cement and the role of sulfate This paper reports the strength promoting mechanism of alkanolamines on limestone calcined clay cement LC3 The hydration kinetics phase formation and microstructure of LC3 with triethanolamine TEA or triisopropanolamine TIPA were
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