المؤلفون: Shu Mei Yu, Lin Nu Lu, Yong Jia He, Shu Guang Hu

المصدر: Advanced Materials Research. :785-788

مصطلحات موضوعية: Calcite, Materials science, General Engineering, Mineralogy, engineering.material, medicine.disease, Portlandite, chemistry.chemical_compound, chemistry, Chemical engineering, Scientific method, engineering, medicine, Dehydration, Calcium silicate hydrate, Quartz

الوصف: Investigation on the continuous dehydration process of calcium silicate hydrate with C/S 1.5 during heating in the air was carried out. Results showed that the heating at 200°C of C-S-H resulted in decreasing basal spacing from 1.2 nm to 1.0 nm, and the basal spacing disappeared as the temperature raised to 400°C. Small amount of the dehydrated calcium silicate hydrate, portlandite and calcite were detectable in the heated sample at 400°C. The phases in the samples heated at 500°C and 650°C are β-C2S, quartz, and calcite. At 800°C and 900°C, α′-C2S, β-C2S, and quartz are main phases in the heated sample.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::3ce209aef3215eb4aa7226e2816c4b2eTest
https://doi.org/10.4028/www.scientific.net/amr.287-290.785Test

المؤلفون: Shu Guang Hu, Lin Nu Lu, Yong Jia He

المصدر: Advanced Materials Research. :1275-1279

مصطلحات موضوعية: Geopolymer, Compressive strength, Materials science, Ground granulated blast-furnace slag, Metallurgy, General Engineering, macromolecular substances, Composite material, Alkali metal, Microstructure, Porosity, Metakaolin, Amorphous solid

الوصف: Compound binding material was prepared by the alkali activation of metakaolin and ground granulated blast furnace slag. Hydration product components, microstructure and mechanical properties of the hardened paste were investigated by IR, XRD, SEM, MIP, and compressive strength measurement. Results indicated that hydration products included C-S-H and geopolymer, and both of them were amorphous although there were differences in their structure and morphology. When the dosage of slag was less than 50%, the compressive strength of hardened paste increased as the dosage increased, which was mainly because C-S-H produced by the reaction of GGBFS and alkali filled void in geopolymer phase, and part of unreacted slag particles acting as microaggregate to prevent from extension of microcrack in the hardened paste, so the porosity of hardened paste decreased and compressive strength increased.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::5bd35b879bee465a45f427f3cff7aaa5Test
https://doi.org/10.4028/www.scientific.net/amr.287-290.1275Test

المؤلفون: Shu Guang Hu, Jian Ming Zhang, Yong Jia He, Lin Nu Lu

المصدر: Advanced Materials Research. :1193-1196

مصطلحات موضوعية: Aqueous solution, Materials science, Precipitation (chemistry), Scanning electron microscope, Inorganic chemistry, General Engineering, Alkali metal, Microstructure, Calcium nitrate, chemistry.chemical_compound, chemistry, Specific surface area, Fourier transform infrared spectroscopy, Nuclear chemistry

الوصف: Synthetic C–S–H and C-A-S-H samples with different Ca/Si molar ratios (1.0 and 1.5) were prepared by precipitation from solution. The effects of incorporations of aluminum ion into C-S-H gels on their microstructure were studied by applying Fourier Transform Infrared Spectroscopy (FTIR), BET nitrogen adsorption and scanning electron microscopy (SEM). Results show that in FTIR spectra, peaks nearing 970 cm-1 and 450 cm-1 wave number change obviously with the substitution of Al3+into C/S1.0 C-S-H. In BET diagram, it also can be found that the substitution of Al3+into C/S1.0 C-S-H lower the specific surface area. Furthermore, SEM graphs also show that the morphology change in C/S=1.0 C-S-H after the substitution of aluminum ion. However, little difference can be found in FTIR spectra and BET diagrams after Al3+ doped into C/S1.5 C-S-H. So, it can be concluded that the effects of the substitution of aluminum ion on the structure and morphology of C-S-H are affected by Ca/Si molar ratio

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::0a0607586dc52911148cce44d521dc6eTest
https://doi.org/10.4028/www.scientific.net/amr.287-290.1193Test

المؤلفون: He, Yong Jia, Lu, Lin Nu, Hu, Shu Guang

المصدر: Advanced Materials Research; July 2011, Vol. 287 Issue: 1 p1275-1279, 5p

مستخلص: Compound binding material was prepared by the alkali activation of metakaolin and ground granulated blast furnace slag. Hydration product components, microstructure and mechanical properties of the hardened paste were investigated by IR, XRD, SEM, MIP, and compressive strength measurement. Results indicated that hydration products included C-S-H and geopolymer, and both of them were amorphous although there were differences in their structure and morphology. When the dosage of slag was less than 50%, the compressive strength of hardened paste increased as the dosage increased, which was mainly because C-S-H produced by the reaction of GGBFS and alkali filled void in geopolymer phase, and part of unreacted slag particles acting as microaggregate to prevent from extension of microcrack in the hardened paste, so the porosity of hardened paste decreased and compressive strength increased.

المؤلفون: He, Yong Jia, Lu, Lin Nu, Zhang, Jian Ming, Hu, Shu Guang

المصدر: Advanced Materials Research; July 2011, Vol. 287 Issue: 1 p1193-1196, 4p

مستخلص: Synthetic C–S–H and C-A-S-H samples with different Ca/Si molar ratios (1.0 and 1.5) were prepared by precipitation from solution. The effects of incorporations of aluminum ion into C-S-H gels on their microstructure were studied by applying Fourier Transform Infrared Spectroscopy (FTIR), BET nitrogen adsorption and scanning electron microscopy (SEM). Results show that in FTIR spectra, peaks nearing 970 cm^-1 and 450 cm^-1 wave number change obviously with the substitution of Al³⁺ into C/S1.0 C-S-H. In BET diagram, it also can be found that the substitution of Al³⁺ into C/S1.0 C-S-H lower the specific surface area. Furthermore, SEM graphs also show that the morphology change in C/S=1.0 C-S-H after the substitution of aluminum ion. However, little difference can be found in FTIR spectra and BET diagrams after Al³⁺ doped into C/S1.5 C-S-H. So, it can be concluded that the effects of the substitution of aluminum ion on the structure and morphology of C-S-H are affected by Ca/Si molar ratio

المؤلفون: Lu, Lin Nu, Yu, Shu Mei, He, Yong Jia, Hu, Shu Guang

المصدر: Advanced Materials Research; July 2011, Vol. 287 Issue: 1 p785-788, 4p

مستخلص: Investigation on the continuous dehydration process of calcium silicate hydrate with C/S 1.5 during heating in the air was carried out. Results showed that the heating at 200°C of C-S-H resulted in decreasing basal spacing from 1.2 nm to 1.0 nm, and the basal spacing disappeared as the temperature raised to 400°C. Small amount of the dehydrated calcium silicate hydrate, portlandite and calcite were detectable in the heated sample at 400°C. The phases in the samples heated at 500°C and 650°C are β-C2S, quartz, and calcite. At 800°C and 900°C, α′-C2S, β-C2S, and quartz are main phases in the heated sample.