The influence of the fineness, concentration, and chemico-mineralogical composition of limestone on the workability, reaction kinetics, compressive strength, microstructure, and binder gel characteristics of sodium carbonate–based waste-activated …

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Keywords: Thermal treatment, Microstructure, Compressive strength, Fly ash and blended cement This study aimed to investigate the effect of heat treatment on microstructure and phase composition of pastes containing fly ash (FA) and limestone (LS). Two groups of cement pastes were prepared. In the first group, Portland cement (OPC) has been

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Effects of Nano-CaCO 3/Limestone Composite Particles on the ... microstructure of the specimens based on backscattered electron imaging. A small fractured sample was soaked in ... Table 1: Chemical composition of cement and limestone (%). Oxide Portland cement Limestone SiO 2 21.06 4.38 Al 2O 3 6.13 1.56 Fe 2O 3 2.61 0.76

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Using limestone (CaCO 3) and/or dolomite (CaMg(CO 3) 2) as the additives, crystalline structure breakdown of potassium feldspar is achieved by high-temperature treatment and a K-containing multi-nutrient silicate fertilizer is thus produced. Effect of sintering temperature on the available nutrient contents, mineral phases, and microstructure ...

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composition and specific surface according to Blaine method) is given in Table 1.The composition of concrete mixtures is given in Table 2. Table 1. Chemical composition of microfillers and Blaine specific surface. Limestone powder Fly ash Component L-1 L-2 FA SiO2 1,35 0,13 52,77 Fe2O3 0,50 0,20 7,32 Al2O3 0,46 0,20 24,98 CaO 51,60 52,38 3,42

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There would be a synergic effect between limestone and SCMs in Portland cement, which infers the filler effect of limestone and SCMs refining microstructure, the dilution effect of reducing hydration product, and the chemical effect of producing calcium carboaluminate, sulfoaluminate, and silicates to reduce porosity. It is predicted that the ...

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• Microstructure controls the macroscopic properties of limestone. - Abstract: Limestone is a common rock used in many buildings and found in underground engineering projects. After exposure to heat, for example, the occurrence of fires, the stability of limestone structures is mostly affected, which may have safety repercussions.

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Microstructure development of limestone blended cement 1 Reply Though the chemical reaction of the fine particles of limestone in cement paste is limited to a low extent due to its inert property the addition of limestone particles has significant effect on the microstructure development ... Therefore the purpose of this study was to ...

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Limestone rock aggregates were collected from the Fayoum depression southwest of Cairo, Egypt. The chemical and mineral composition as well as the microstructure …

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Microstructure analysis results demonstrated that 7 days cement composition (Fig. 7a) without fine limestone powder has porous open-grain structure with macropores predominance. Dolomite addition results in increasing of quantity of centres which initiate more intensive cristallyzation that, in turn, results in hydration rate increasing.

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Limestone represents the main raw material for ordinary Portland cement clinker production. In this study eight natural limestones from different geological environments were chosen to prepare raw meals for clinker manufacturing, aiming to define a parameter controlling the burnability. First, limestones were characterized by X-Ray Fluorescence, X-Ray Powder Diffraction and Optical Microscopy ...

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The microstructure characteristic, mechanical behaviors, pore distribution, and AE characteristic of limestone have been investigated [39–41]. Yavuz et al. [ 42 ] investigated the changes of physical properties of five carbonate rocks (two marbles …

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The microstructure was carried out by the Scanning Electron Microscope of the type Jeol JSM-T20. Effect of curing temperature on the thermal expansion and phase composition of hydrated limestone-slag cement Ceramics − Silikáty 48 (3) 110-116 (2004) 111 Table 1. Chemical composition of starting materials (wt.%). oxide OPC GBFS LS SiO 2 20.50 ...

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The limestone was purchased from Jinan city, Shandong Province, and was ground for 30 minutes. The mean diameter of the ground limestone is 8.26 μm, while the specific surface area is up to 574 m2∙kg-1. Table 1. The composition of the calcined clay and limestone (mass fraction/%). ComponentsCaOSiO 2 Al 2 O 3 K 2 O 2 O 3 FeTiO 2 LOI*

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Indian iron ore fines with high alumina content (~2.5% Al 2 O 3 ) resulted in poor quality pellets and a study was under taken to establish suitable pellet chemistry through proper fluxing agents. Limestone fluxed pellets were prepared at varying basicity (0 to 0.8) and pyroxenite fluxed pellets at varying MgO contents (0 to 3%) to study their effect on the metallurgical properties.

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Limestone powder has been widely used in concrete structures because of its easy availability and positive effect on reducing the heat of hydration. The addition of limestone powder has a significant influence on the hydration and microstructure of cement paste and therefore affects the strength and durability of concrete.

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Experimental process. To study the effects of microstructure and composition on the tensile strength of gypsum rocks, X-ray fluorescence spectrometry (XRF), elementary analysis and X …

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Later, when the melt appears this correlation vanishes; however differences in the early burnability still reflect on the final clinker composition and texture. Effects of limestone petrography and calcite microstructure on OPC clinker raw meals burnability / M. Galimberti, N. Marinoni, G. Della Porta, M..I. Marchi, M. Dapiaggi.

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Because of its environmental and economic benefits, part of cement is replaced by limestone fillers (LS). However, the effect of LS on the chemical degradation of cement-based materials is still unclear. In this study, accelerated leaching and carbonation were applied on cement pastes to study the effects of LS replacement on the degradation rates and microstructural alterations of degraded ...

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Vanadium−titanium magnetite (VTM) is an important raw material for ironmaking under the situation of increasingly demanding scarce resources. To further improve the metallurgical properties of pellets, and to satisfy the requirements of blast furnace slag basicity, finely ground dolomite and limestone have been added to the pellet. In this study, the effect of finely ground dolomite and ...

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The effect of La203-doping on the sinterability of Egyptian dolomite and limestone-derived lime on firing up to 1600°C was investigated. The La203/CaO ratios ranged between 0.4 and 1.5 mole% of the investigated materials. The composition of the phases formed on firing and the microstructures of the obtained grains were studied using chemical analysis, X-ray diffraction and reflected light ...

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For sample with limestone fillers, calcite might precipitate preferentially on limestone particles than on portlandite and C–S–H phases (shown later in Fig. 13), which promoted the CO 2 uptake. Additionally, the dilution effect did contribute to larger CO 2 uptake of L10-cont compared L0-cont (i.e. more cement in L0-cont).

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The effect of limestone on the hydration and microstructural development of ultra high performance concrete (UHPC) with different levels of replacement (34%, 54% and 74% by volume) was investigated. Up to 54% replacement of cement by limestone the mixes showed better workability and higher compressive strength (170 MPa at 56 days for 54% addition) compared to a classical mix (155 …

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Acid treatment is widely used for exploiting tight limestone reservoirs, and how acid affects the microstructure and mechanical property of tight limestone needs deeper understanding. Tight limestone cores from Middle Ordovician Yijianfang Formation in Tarim Basin, China, were collected to conduct acid coreflooding tests, simulating acid–rock reaction process between tight limestone and ...

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Liu Shuhua and Yan Peiyu, Effect of limestone powder on microstructure of concrete, journal of wuhan university of technology-mater. Sci. Ed., Vol. 25 N°2, p. 328-331, Apr. 2010. In article [18] Hamid S-A., Zeitschrift für Kristallographie, n° 154, 1981, p. 189. In article [19]

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Limestone rock aggregates were collected from the Fayoum depression southwest of Cairo, Egypt. The chemical and mineral composition as well as the microstructure of the aggregates was studied ...

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Limestone and slag exert physico-chemical effects on cement hydration and the resultant microstructure. In limestone containing cements, the carbonate species interact with the dissolved aluminates to form carboaluminates, thus stabilizing ettringite. Reaction of slag mainly produces

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In this study the solder alloys SnAg3.5, SnAg3.0Cu0.5, SnAg3.8Cu0.7 and SnAg2.7Cu0.4Ni0.05 have been analysed in order to determine variations in microstructure caused by cooling rate, solder composition and ball diameter. Solder spheres with a diameter of approx. Ø 1100 μm, Ø 590 μm, Ø 270 μm and Ø 130 μm were solidified with cooling rates of 0.14K/s, 1.1K/s and …

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The Effect of Chemical Composition and Thermal Sprayed Method on the Chromium and Tungsten Carbides Coatings Microstructure . Maria W. Richert, Borys Miku. ł. owski, Pawel Pa. ł. ka, Agnieszka Hotlo. ś, Malgorzata Perek-Nowak . Faculty of Non-Ferrous Metals, AGH, University of Science & Technology, Kraków, Poland. Email: [email protected]

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Apr 16, 2018· Table 4.7. Main and interaction effect of limestone particle size, housing system and strain on bone mineral density, content and area at 52 wk of age _ 115 Table 4.8. The overall effect of particle size of limestone, housing system and strain on odds of hens having fractured, indented, and curved keel bones. Read More

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