The Experts below are selected from a list of 1716 Experts worldwide ranked by ideXlab platform
Hai Nan Zhao - One of the best experts on this subject based on the ideXlab platform.
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Research on Sand Gradation to Ultra Strength Grouting Material Properties
Applied Mechanics and Materials, 2014Co-Authors: Xiao Ping Zhang, Hai Nan ZhaoAbstract:The gradation of coarse sand, medium sand and fine sand on fluidity initial, Final Setting Time, flexural strength, compressive strength, and other properties and structure, of ultra early strength grouting material, was explored. The quartz sand gradation of cement sand ratio 1.0 was systematically studied. The results showed that, the coarse sand, medium sand and fine sand mixed according to the reasonable distribution, when glue sand ratio was 1.0-1.5, ultra-early-strength grouting material, with Final Setting Time for 50-60(min), the initial fluidity greater than 320(mm), 0.5h fluidity greater than 280(mm), 2h compressive strength of 35.6(MPa), 1d flexural strength greater than 13(MPa), 28d compressive strength over 93(MPa), achieved the free vibration.
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Early Strength Agent on the Properties of Reinforcement Materials Research
Applied Mechanics and Materials, 2013Co-Authors: Xiao Ping Zhang, Hai Nan ZhaoAbstract:In the trial, the author explores sodium nitrite, triethanolamine and sodium on fluidity initial and Final Setting Time, flexural strength and compressive strength and other properties, of early strength reinforcement material. The results showed that, when sodium nitrite content is 0.2%, triethanolamine content is 0.05%, the dosage of sodium sulfate is 0.8%, Final Setting Time for 58min, the initial flow greater than 320[mm], 30min flow greater than 280[mm], 2h compressive strength of 30[MPa], 1d bending greater than 10[MPa], 28d compressive strength greater than 90[MPa], on the early strength reinforcement, meet construction requirements.
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Several Common Retarders on Performance of Ultra-Early-Strength Grouting Material
Applied Mechanics and Materials, 2013Co-Authors: Xiao Ping Zhang, Hai Nan ZhaoAbstract:To explore retarders on performance of ultra-early strength grouting material, Retarder, which are commonly used in the market after a preliminary screening, are further tested and analyzed for initial fluidity, Setting Time and mechanical strength properties of super early strength grouting material. The results show that: When borax content is 0.4%, the initial fluidity, Final Setting Time, workability, mechanical strength are the best.
Xiao Ping Zhang - One of the best experts on this subject based on the ideXlab platform.
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Research on Sand Gradation to Ultra Strength Grouting Material Properties
Applied Mechanics and Materials, 2014Co-Authors: Xiao Ping Zhang, Hai Nan ZhaoAbstract:The gradation of coarse sand, medium sand and fine sand on fluidity initial, Final Setting Time, flexural strength, compressive strength, and other properties and structure, of ultra early strength grouting material, was explored. The quartz sand gradation of cement sand ratio 1.0 was systematically studied. The results showed that, the coarse sand, medium sand and fine sand mixed according to the reasonable distribution, when glue sand ratio was 1.0-1.5, ultra-early-strength grouting material, with Final Setting Time for 50-60(min), the initial fluidity greater than 320(mm), 0.5h fluidity greater than 280(mm), 2h compressive strength of 35.6(MPa), 1d flexural strength greater than 13(MPa), 28d compressive strength over 93(MPa), achieved the free vibration.
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Research on the Compound early Strength Agent to the Performance of Super High early Strength Grouting Material
Applied Mechanics and Materials, 2013Co-Authors: Xiao Ping Zhang, Tong Feng ZhaoAbstract:The effect of sodium sulfate, triethanolamine and early strength agent A on the early strength reinforcement material Final Setting Time, flexural strength and compressive strength and structure were investigated. The results show that the composite of sodium sulfate, triethanolamine and early strength agent according to a reasonable proportion, the dosage of 0.35% -0.40% (in cementitious material quality), the Final Setting Time of early strength material for 50 to 60 min, Initial fluidity over 320mm, 0.5h flow degree greater than 280mm, 1d bending greater than 12MPa and 28d compressive strength greater than 80MPa, meet the requirements.
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Early Strength Agent on the Properties of Reinforcement Materials Research
Applied Mechanics and Materials, 2013Co-Authors: Xiao Ping Zhang, Hai Nan ZhaoAbstract:In the trial, the author explores sodium nitrite, triethanolamine and sodium on fluidity initial and Final Setting Time, flexural strength and compressive strength and other properties, of early strength reinforcement material. The results showed that, when sodium nitrite content is 0.2%, triethanolamine content is 0.05%, the dosage of sodium sulfate is 0.8%, Final Setting Time for 58min, the initial flow greater than 320[mm], 30min flow greater than 280[mm], 2h compressive strength of 30[MPa], 1d bending greater than 10[MPa], 28d compressive strength greater than 90[MPa], on the early strength reinforcement, meet construction requirements.
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Several Common Retarders on Performance of Ultra-Early-Strength Grouting Material
Applied Mechanics and Materials, 2013Co-Authors: Xiao Ping Zhang, Hai Nan ZhaoAbstract:To explore retarders on performance of ultra-early strength grouting material, Retarder, which are commonly used in the market after a preliminary screening, are further tested and analyzed for initial fluidity, Setting Time and mechanical strength properties of super early strength grouting material. The results show that: When borax content is 0.4%, the initial fluidity, Final Setting Time, workability, mechanical strength are the best.
Maria Giovanna Gandolfi - One of the best experts on this subject based on the ideXlab platform.
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properties of bioroot rcs a tricalcium silicate endodontic sealer modified with povidone and polycarboxylate
International Endodontic Journal, 2017Co-Authors: Francesco Siboni, Fausto Zamparini, Paola Taddei, Carlo Prati, Maria Giovanna GandolfiAbstract:Aim To evaluate the chemical and physical properties of a tricalcium silicate root canal sealer containing povidone and polycarboxylate (BioRoot RCS), a calcium silicate MTA based sealer containing a salicylate resin (MTA Fillapex), a traditional eugenol-containing sealer (Pulp Canal Sealer) and an epoxy resin-based root canal sealer (AH Plus). Methodology Calcium release, pH, Setting Time, water sorption, (volume of open pores, volume of impervious portion, apparent porosity) porosity and weight loss were measured. The ability to nucleate calcium phosphates (CaP) after ageing 28 days in a simulated body fluid was evaluated using ESEM-EDX and micro-Raman spectroscopy. Data were statistically analyzed (p=0.05) using one-way ANOVA (Setting Time, radiopacity, solubility, water sorption, porosity) or two-way ANOVA (ion release tests). Results BioRoot RCS had a Final Setting Time of 300 min and adequate radiopacity (5.2 mmAl). It demonstrated the highest (p<0.05) and more prolonged ability to release calcium ions (721 ppm at 3h) and to increase the pH (11-12) (p<0.05); B-type carbonated apatite deposits were found on aged BioRoot RCS (biointeractivity-related CaP-forming ability). A Final Setting Time of 270 min and good calcium release (17.4 ppm at 3h) were measured for MTA Fillapex; apatite deposits were present on aged samples. No calcium release and no alkalizing activity were measured for Pulp Canal Sealer and AH Plus; no CaP nucleation was detected on aged Pulp Canal Sealer, and some apatite deposits were found on aged AH Plus (chemi/physisorption-related CaP-deposition). Higher and significantly different (p<0.05) porosity, water sorption and solubility were measured for the two calcium silicate sealers, especially for BioRoot RCS. Conclusions BioRoot RCS had bioactivity with calcium release, strong alkalizing activity and apatite forming ability, adequate radiopacity. This article is protected by copyright. All rights reserved.
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Setting Time and expansion in different soaking media of experimental accelerated calcium-silicate cements and ProRoot MTA
Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology, 2009Co-Authors: Maria Giovanna Gandolfi, Kelli Agee, Franklin Tay, Francesco Iacono, Francesco Siboni, David Henry Pashley, Carlo PratiAbstract:Objectives: The Setting Time and the expansion in deionized water, phosphate-buffered saline (PBS), 20% fetal bovine serum (FBS)/80% PBS or hexadecane oil of experimental accelerated calcium-silicate cements and ProRoot MTA were evaluated. Study design: Different compounds such as sodium fluoride, strontium chloride, hydroxyapatite, and tricalcium phosphate were separately added to a basic experimental calcium-silicate cement to test their effect on Setting and expansion. The initial and Final Setting Times were determined using appropriate Gilmore needles. A linear variable differential transformer (LVDT) device was used to test the restricted hygroscopic linear expansion over 180 minutes of cements immersed in different solutions. Results were statistically compared using a 2-way ANOVA test (cement type versus solution type). Results: All experimental cements showed initial Setting Times between 28 and 45 minutes and Final Setting Times between 52 and 80 minutes. MTA showed a Final Setting Time of 170 minutes. Final Setting Time of all experimental cements was faster than MTA. All cements showed slight (0.04%-0.77%) expansion in water, PBS, or FBS/PBS. Only fluoride-containing cement showed a significant expansion in water (6.68%) and in PBS (6.72%). The PBS/FBS contamination significantly reduced the expansion of fluoride-containing cement (2.98%) and MTA (0.07%). In contrast, cements showed a slight shrinkage when immersed in hexadecane, especially fluoride-containing cement. Conclusions: The study demonstrated that: (1) the Setting Time of calcium-silicate cements may be effectively reduced; (2) the expansion is a water dependent mechanism owing to water uptake, because no expansion occurred in cements immersed in oil; (3) a correlation between Setting Time and expansion in water and PBS exists; (4) fluorine-containing cement showed a significant expansion in water and in PBS; (5) the immersion in FBS/PBS strongly reduced the expansion of MTA and fluoride-doped cement suggesting that fluid contamination (ie, blood) during surgical procedures may greatly affect the expansion of some calcium-silicate cements. © 2009.
N Gowripalan - One of the best experts on this subject based on the ideXlab platform.
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simultaneous measurement of shrinkage and temperature of reactive powder concrete at early age using fibre bragg grating sensors
Cement & Concrete Composites, 2007Co-Authors: Allan C L Wong, Paul Childs, Richard Berndt, Tony Macken, Gangding Peng, N GowripalanAbstract:The physical properties of reactive powder concrete (RPC) at early-age, i.e., the first 24 h from casting, and up to an age of 7 days is investigated experimentally using fibre Bragg gratings (FBGs), a type of fibre-optic sensors. A number of FBG sensors are multiplexed together and embedded directly into the RPC specimens, and the shrinkage and temperature change are measured directly and simultaneously. The Final Setting Time and specimen size effect were also investigated. Results showed that there is an interplay between the shrinkage and temperature. The overall shrinkage for 7 days is 488 μe, with the early-age shrinkage contributing about 77% of this. The temperature curve exhibits a double peak behaviour, with the first peak appears at about 7 h, which is the Final Setting Time. There is a size effect in that smaller prisms have a higher overall shrinkage and lower temperature change than larger prisms.
Enrique Lopezcabarcos - One of the best experts on this subject based on the ideXlab platform.
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increase of the Final Setting Time of brushite cements by using chondroitin 4 sulfate and silica gel
Journal of Materials Science: Materials in Medicine, 2007Co-Authors: F Tamimimarino, J Mastio, Carmen Rueda, Luis Blanco, Enrique LopezcabarcosAbstract:Chondroitin 4-sulfate (C4S) is a bioactive glycosaminoglycan with inductive properties in bone and tissue regeneration. Dicalcium phosphate dehydrate cements (known as brushite) are biocompatible and resorbable materials used in bone and dental surgery. In this study we analyzed the effect of C4S on the Setting of a calcium phosphate cement and the properties of the resulting material. Brushite based cement powder was synthesised by mixing monocalcium phosphate with β-tricalcium phosphate and sodium pyrophosphate. When the concentration of C4S, in the liquid added to the cement powder, was between 1 and 8% the cement Final Setting Time increases. Furthermore, the cement diametral tensile strength remains unaffected when solutions with concentrations of C4S below 5% were used, but decreases at higher C4S concentrations. Calorimetric analysis showed that the cements prepared with C4S alone and in combination with silica gel have a greater content of hydrated water. We concluded from our study that the addition of small amounts of C4S increases the cement Setting Time without affecting its diametral tensile strength and at the same Time improves the cement’s hydrophilicity.