Effect of Aluminum Insertion Material on the Properties of AAC

2016 ◽  
Vol 703 ◽  
pp. 406-410
Author(s):  
Yun Feng Pan ◽  
Wan Ming Huang ◽  
Ya Qing Jiang ◽  
Qiang Song
Keyword(s):  
Volume Ratio ◽  
High Strength ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Hydration Degree ◽  
Scanning Electron Microscope Analysis ◽  
X Ray ◽  
Electron Microscope Analysis ◽  
Aerated Concrete ◽  
Scanning Electron

Study on the compressive strength, shrinkage and effect of aluminum insertion materials on the hydration products of Autoclaved Aerated Concrete (AAC). The types and properties of hydration products are studied by X-Ray Diffraction Analysis (XRD), Differential Thermal Analysis (DTA), Scanning Electron Microscope analysis (SEM) and so on. The results showed that the strength and the shrinkage resistance capability of the product could be improved effectively. Al3+successfully doped into C-S-H gel and tobermorite crystals, then replaced si4+of tobermorite and formed the system of C-A-S-H. Tobermorite in aluminum insertion aerated concrete is smaller and more compact. All hydration products interlace to form a whole, then the structure turns denser. Low porosity, high crystal gel volume ratio and high hydration degree are the key of the high strength aluminum insertion aerated concrete. Aluminum insertion materials improve the performance of the products.

Polymorphic Changes of Calcite Carbonate Sediment in Aqueous Solution

2012 ◽  
Vol 549 ◽  
pp. 113-117
Author(s):  
Jian Xin Chen ◽  
Quan Sun ◽  
Teng Jiao Liu ◽  
Joachim Ulrich ◽  
Lei Xie
Keyword(s):  
Aqueous Solution ◽  
Electron Microscope ◽  
X Ray Diffraction ◽  
Carbonate Sediment ◽  
Scanning Electron Microscope Analysis ◽  
X Ray ◽  
Industry Applications ◽  
Electron Microscope Analysis ◽  
Higher Temperature ◽  
Scanning Electron

Calcium carbonate (CaCO3) is abundant in nature, and is also an important material applied in industry as pigment, filler material, etc. It is a challenge to control the desired CaCO3 properties for industry applications. In this study, three typical morphologies of CaCO3, calcite, aragonite and vaterite were prepared. The crystallization temperature and addition of acrylic-acrylate-sulfosalt copolymer play a significant effect on the polymorph change of CaCO3 sediment. Higher temperature promoted the formation of aragonite, while more additives tended to form the vaterite. The x-ray diffraction and scanning electron microscope analysis confirmed the formation of CaCO3 with various polymorphs.

Study on the Effect of Condensate-Type and Copolymer-Type Combined Superplasticizers on Hydration of Cement

2016 ◽  
Vol 703 ◽  
pp. 360-364
Author(s):  
Yun Feng Pan ◽  
Ya Qing Jiang ◽  
Si Jia Zhang
Keyword(s):  
Steric Effect ◽  
Chemical Shrinkage ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Mineral Phase ◽  
Early Hydration ◽  
Scanning Electron Microscope Analysis ◽  
X Ray ◽  
Electron Microscope Analysis ◽  
Double Hydroxides

For the limitation of single-component superplasticizer, condensate-type and copolymer-type combined superplasticizers were prepared. The adsorption of compound superplasticizers on cement paste was tested by Total Organic Carbon (TOC) measurement. Influences of superplasticizers on early hydration process of cement and Organo-mineral phase formation were studied by X-Ray Diffraction Analysis (XRD), Scanning Electron Microscope analysis (SEM) and so on. The results show that owing to the electrostatic repulsion and steric effect cooperative mechanism, condensate-type and copolymer-type combined superplasticizers reduce the superplasticizers adsorption in cement minerals and its hydration products surface, delay the process of hydration of C3A, form Organic-Layered double hydroxides (LDH), increase the early chemical shrinkage and promote the growth of cement early hydration and Ettringite

Utilization of Desulfuration Residues in Non-Autoclaved Aerated Concrete

2011 ◽  
Vol 250-253 ◽  
pp. 707-710
Author(s):  
Fang Xian Li ◽  
You Zhi Chen ◽  
Qi Jun Yu ◽  
Jiang Xiong Wei
Keyword(s):  
Compressive Strength ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Bulk Density ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
Autoclaved Aerated Concrete ◽  
Aerated Concrete ◽  
Scanning Electron

Desulfuration residues were used as aggregate to produce Non-autoclaved aerated concrete. The effects of water-hinder ratio, casting temperature on the gas forming behavior, and those of desulfuration residue content on the compressive strength and bulk density of aerated concrete were investigated. The types of the hydration products and the microstructure of Non-autoclaved aerated concrete with desulfuration residue were investigated by means of X-ray diffraction and scanning electron microscope. Results show that the optimum replacement amount was determined as 50% and at this rate the compressive strength, bulk density of Non-autoclaved aerated concrete were measured as 2.83 MPa and 543 kg/m3. The hydration products of Non-autoclaved aerated concrete with desulfuration residue are C2SH (A) and C2SH (B) along with ettringite and hydrogarnet phases.

Corrosion Behavior of 13Cr Steel in Different Temperature

2014 ◽  
Vol 937 ◽  
pp. 168-171 ◽  
Author(s):  
Zhi Chao Qiu ◽  
Xiang Liu ◽  
Na Zhang
Keyword(s):  
Electron Microscope ◽  
Corrosion Rate ◽  
Scanning Electron Microscope ◽  
Corrosion Behavior ◽  
X Ray Diffraction ◽  
Scanning Electron Microscope Analysis ◽  
X Ray ◽  
Micro Scale ◽  
Electron Microscope Analysis ◽  
Scanning Electron

Corrosion experiments were applied for 13Cr steel. Through the experiments, the corrosion rate of 13Cr steel in different temperature was tested. The corrosion rate of 13Cr steel was increased with the increase of temperature. Moreover X-ray diffraction analysis and scanning electron microscope analysis were applied to understand the corrosion behavior of 13Cr in micro-scale.

Synthesis of Nickel Hydroxide with Different Morphologies Using an Ionic Liquid

2010 ◽  
Vol 663-665 ◽  
pp. 1163-1166
Author(s):  
Cun Ying Xu ◽  
Yi Xin Hua
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ionic Liquid ◽  
Volume Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Reaction Media ◽  
Solvothermal Conditions ◽  
Facile Route ◽  
Scanning Electron

A new and facile route has been developed to synthesize β-Ni(OH)2 nanostructures using ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) as reaction media under solvothermal conditions. The β-Ni(OH)2 with different morphologies, such as nanoflakes, nanoplatelet and nanorods, can be obtained by controlling the volume ratio of the ionic liquid to water and reaction temperature. The as-prepared products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

Experimental Research on High-Strength Super Sulphate Cement Paste Mixed with Superfine Mineral Admixtures

2014 ◽  
Vol 629-630 ◽  
pp. 150-155
Author(s):  
Jun Wang ◽  
Bao Ying Yu ◽  
Long Yang ◽  
Yu Xin Gao ◽  
Jia Yu Xiang
Keyword(s):  
Silica Fume ◽  
High Strength ◽  
Hydration Product ◽  
Mineral Admixtures ◽  
Hydration Reaction ◽  
X Ray Diffraction ◽  
Cement Ratio ◽  
X Ray ◽  
Early Strength ◽  
Scanning Electron

Aimed at the performance affect of high-strength super sulphate cement (SSC) paste mixed with superfine mineral admixtures, influence of microbead and silica fume replacing SSC quantity on high-strength SSC paste compression strength were studied under water-cement ratio 0.18; Hydration product morphology and phase were further compared by scanning electron microscopy and X-ray diffraction analyzer in this paper. Results show that, compared with sample HS-1, 3-day strength of HS-2 and HS-3 were increased by 5% and 10%, 28d strength basically unchanged; Furthermore, early strength of HS-7 sample slightly higher and late strength basically unchanged. SSC by adding 5% microbead and 3% silica fume (HS-11) has compressive strength 50.8MPa at 3 days and 86.1MPa at 28 days is significantly higher than other samples. Early strength of HS-11sample mainly depends on hydration reaction of SSC and particle filling effect of admixtures, later strength is due to accelerating consumption of gypsum and promoting formation of ettringite.

scholarly journals Evaluation of the Properties of Cemented Liquid Scintillator Wastes under Flooding Scenario in Various Aqueous Media

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
H. El-Didamony ◽  
T. A. Bayoumi ◽  
M. I. Sayed
Keyword(s):  
Electron Microscopy ◽  
Liquid Scintillator ◽  
Aqueous Media ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
Long Period ◽  
Flooding Event ◽  
Predetermined Interval ◽  
Scanning Electron

Experiments simulating flooding scenario in various aqueous media for a long period were carried out to determine the adequacy of cement-clay composite for solidification/stabilization of spent organic radioactive liquid scintillator wastes. The final cement waste form blocks were immersed in three aqueous media, namely, seawater, groundwater, and tapwater. The immersion process lasted for increasing periods up to 540 days. Following each predetermined interval period, physical and mechanical evaluations of the immersed blocks were determined. In addition, the change in the hydration products was followed by X-ray diffraction and infrared spectroscopy as nondestructive analyses to recognize the deterioration in the microstructure that may occur due to the flooding event. Thermal analysis and scanning electron microscopy were performed to confirm the data obtained.

Hydration of sodium phosphate-modified high alumina cement

1994 ◽  
Vol 9 (5) ◽  
pp. 1291-1298 ◽  
Author(s):  
Weiping Ma ◽  
Paul W. Brown
Keyword(s):  
Isothermal Calorimetry ◽  
High Strength ◽  
High Alumina ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Alumina Cement ◽  
X Ray ◽  
Morphological Variations ◽  
High Alumina Cement ◽  
Sodium Phosphates

High strength can be achieved in high alumina cement (HAC) through the incorporation of phosphate-based additions at levels of 10 and 20 wt. %. In order to establish the mechanism that results in higher strength, the effects of a variety of condensed sodium phosphates (NaPO3)n, (NaPO3)n · Na2O, Na5P3O10, and (NaPO3)3 were studied. The influence of these additions on the kinetics of hydration was studied using isothermal calorimetry. The phosphatic additions enhanced reactivity, but x-ray diffraction analyses did not reveal evidence of new crystalline phosphate-containing hydration products. Microstructural evolution was examined in real time using environmental SEM, and hydration products exhibiting distinct morphologies were observed. The features exhibited ranged from amorphic to polygonal shapes, plates, and fibers. These frequently formed between crystalline calcium aluminate hydrate grains and by doing so appear to provide a means to enhance the strengths of these cements. In spite of the morphological variations, companion energy dispersive x-ray analysis showed that the compositions of these products did not vary widely. Their ranges of compositions are 52-60 wt. % Al2O3, 20-26 wt. % P2O5, and 20-24 wt. % CaO.

scholarly journals Effect of Metakaolin on Strength and Efflorescence Quantity of Cement-Based Composites

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Tsai-Lung Weng ◽  
Wei-Ting Lin ◽  
An Cheng
Keyword(s):  
Compressive Strength ◽  
Image Analysis ◽  
Portland Cement ◽  
Detrimental Effect ◽  
Cement Mortar ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
Replacement Ratio ◽  
X Ray ◽  
Scanning Electron

This study investigated the basic mechanical and microscopic properties of cement produced with metakaolin and quantified the production of residual white efflorescence. Cement mortar was produced at various replacement ratios of metakaolin (0, 5, 10, 15, 20, and 25% by weight of cement) and exposed to various environments. Compressive strength and efflorescence quantify (using Matrix Laboratory image analysis and the curettage method), scanning electron microscopy, and X-ray diffraction analysis were reported in this study. Specimens with metakaolin as a replacement for Portland cement present higher compressive strength and greater resistance to efflorescence; however, the addition of more than 20% metakaolin has a detrimental effect on strength and efflorescence. This may be explained by the microstructure and hydration products. The quantity of efflorescence determined using MATLAB image analysis is close to the result obtained using the curettage method. The results demonstrate the best effectiveness of replacing Portland cement with metakaolin at a 15% replacement ratio by weight.

Effect of Preparation on Standard Dry Density and Strength of Foamed Cement by Orthogonal Test

2014 ◽  
Vol 577 ◽  
pp. 1119-1122
Author(s):  
Na Li ◽  
Qi Wang ◽  
Peng Song
Keyword(s):  
Electron Microscopy ◽  
Thermal Conductivity ◽  
High Strength ◽  
Xrd Analysis ◽  
Orthogonal Test ◽  
Dry Density ◽  
Light Weight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

In this paper, we studied the effect of preparation on standard dry density and strength of foamed cement by orthogonal test. The results indicate that the more excellent combination is A1B1C1, namely G1, the standard dry density is 376 kg/m3, the flexural and compressive strengths are 0.43 MPa and 0.8 MPa respectively, and the thermal conductivity is 0.074 W/(m·K), which conforms to the characteristics of light weight and high strength. Fewer Ca (OH)2 crystals and more C-S-H gel generated in G1 through scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis is the reason for its high strength.

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