Preparation and characterization of high and low CaO/SiO2 ratio “pure” C–S–H for chemically bonded ceramics

1988 ◽  
Vol 3 (2) ◽  
pp. 380-386 ◽  
Author(s):  
Shiqun Li ◽  
Delia M. Roy
Keyword(s):  
Mechanical Properties ◽  
Silica Fume ◽  
Calcium Silicate ◽  
Molar Ratio ◽  
Water Density ◽  
Hydration Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bonded Materials

A type of solidified “pure” C–S–H (calcium silicate hydrate) has been prepared by hydrating mixtures of synthesized Ca3SiO5(C3S) and silica fume at very low water/solid (w/s) ratios (< 0.15). The mechanical properties (splitting tensile strength), stoichiometry, and microstructure of hydration products have been investigated. Results are reported here in which 12.03%−41.56% (by weight) silica fume was added to C3S. It has been found that the strength of the materials with CaO/SiO2(C/S) molar ratio of 1.5 is comparatively higher than that of the others, after curing from 1 day to 28 days. The homogeneity and rheology are of direct importance to the formation of the calcium silicate bonding, which influences greatly the mechanical properties. The hydrates are primarily C–S–H with only small amounts of Ca(OH)2. The compositions of the solidified C–S–H are (1.33–1.37) CaO·SiO2. (1.02–1.21) H2O and (1.40–1.19)CaO·SiO2.(0.68–0.91)H2O for mixtures of C/S = 1.5 and 0.83, respectively. The characterization of the chemically bonded materials by Wn (nonevaporable water), density, x-ray diffraction, and scanning electron microscopy (SEM) studies has been carried out. The relationships between these characteristics and the strength are discussed.

scholarly journals Copper Containing Glass-Based Bone Adhesives for Orthopaedic Applications: Glass Characterization and Advanced Mechanical Evaluation

2020 ◽  
Author(s):  
Sahar. Mokhtari ◽  
Anthony.W. Wren
Keyword(s):  
Mechanical Properties ◽  
Photoelectron Spectroscopy ◽  
Structural Changes ◽  
Viscoelastic Behavior ◽  
Polymer Chains ◽  
Nano Particles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Compression Data

AbstractThis study addresses issues with currently used bone adhesives, by producing novel glass based skeletal adhesives through modification of the base glass composition to include copper (Cu) and by characterizing each glass with respect to structural changes. Bioactive glasses have found applications in fields such as orthopedics and dentistry, where they have been utilized for the restoration of bone and teeth. The present work outlines the formation of flexible organic-inorganic polyacrylic acid (PAA) – glass hybrids, commercial forms are known as glass ionomer cements (GICs). Initial stages of this research will involve characterization of the Cu-glasses, significant to evaluate the properties of the resulting adhesives. Scanning electron microscopy (SEM) of annealed Cu glasses indicates the presence of partial crystallization in the glass. The structural analysis of the glass using Raman suggests the formation of CuO nanocrystals on the surface. X-ray diffraction (XRD) pattern and X-ray photoelectron spectroscopy (XPS) further confirmed the formation of crystalline CuO phases on the surface of the annealed Cu-glass. The setting reaction was studied using Fourier transform infrared spectroscopy (ATR-FTIR). The mechanical properties of the Cu containing adhesives exhibited gel viscoelastic behavior and enhanced mechanical properties when compared to the control composition. Compression data indicated the Cu glass adhesives were efficient at energy dissipation due to the reversible interactions between CuO nano particles and PAA polymer chains.

Stability of sodalite relative to nepheline in NaCl–H2O brines at 750 °C: Implications for hydrothermal formation of sodalite

2020 ◽  
Vol 58 (1) ◽  
pp. 3-18 ◽  
Author(s):  
Jonathan B. Schneider ◽  
David M. Jenkins
Keyword(s):  
Infrared Spectroscopy ◽  
Constant Temperature ◽  
Molar Ratio ◽  
Standard State ◽  
X Ray Diffraction ◽  
Cage Structure ◽  
X Ray ◽  
Brine Concentration

ABSTRACT Formation of the feldspathoid sodalite (Na6Al6Si6O24·2NaCl) by reaction of nepheline (NaAlSiO4) with NaCl-bearing brines was investigated at 3 and 6 kbar and at a constant temperature of 750 °C to determine the brine concentration at which sodalite forms with variation in pressure. The reaction boundary was located by reaction-reversal experiments in the system NaAlSiO4–NaCl–H2O at a brine concentration of 0.16 ± 0.08 XNaCl [= molar ratio NaCl/(NaCl + H2O)] at 3 kbar and at a brine concentration of 0.35 ± 0.03 XNaCl at 6 kbar. Characterization of the sodalite using both X-ray diffraction and infrared spectroscopy after treatment in these brines indicated no obvious evidence of water or hydroxyl incorporation into the cage structure of sodalite. The data from this study were combined with earlier results by Wellman (1970) and Sharp et al. (1989) at lower (1–1.5 kbar) and higher (7–8 kbar) pressures, respectively, on sodalite formation from nepheline and NaCl which models as a concave-down curve in XNaCl – P space. In general, sodalite buffers the concentration of neutral aqueous NaCl° in the brine to relatively low values at P &lt; 4 kbar, but NaCl° increases rapidly at higher pressures. Thermochemical modeling of these data was done to determine the activity of the aqueous NaCl° relative to a 1 molal (m) standard state, demonstrating very low activities (&lt;0.2 m, or 1.2 wt.%) of NaCl° at 3 kbar and lower, but rising to relatively high activities (&gt;20 m, or 54 wt.%) of NaCl° at 6 kbar or higher. The results from this study place constraints on the concentration of NaCl° in brines coexisting with nepheline and sodalite and, because of the relative insensitivity of this reaction to temperature, can provide a convenient geobarometer for those localities where the fluid compositions that formed nepheline and sodalite can be determined independently.

Synthesis and Characterization of 3Y-TZP by Gel Solid-State Method

2011 ◽  
Vol 412 ◽  
pp. 61-64
Author(s):  
Xiao Bo Wu ◽  
Da Zhi Sun ◽  
Dan Yu Jiang ◽  
Hai Fang Xu ◽  
De Xin Huang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Solid State ◽  
Sintering Behavior ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
X Ray ◽  
Powder Particles ◽  
State Method ◽  
Average Size

3Y-TZP powder has been successfully synthesized by gel solid-state method. The structural phases of powder particles were analyzed by X-ray diffraction and the morphology was analyzed by scanning electron microscopy. The average size of grains was 230 nm. The sintering behavior, mechanical properties and microstructure of 3Y-TZP ceramics sintered by this powder were investigated. The experiment results showed that the mechanical properties of ceramics were excellent.

Preparation and Characterization of PVA-Collagen Composite Fibers

2011 ◽  
Vol 236-238 ◽  
pp. 83-86 ◽  
Author(s):  
Xian Hui Sun
Keyword(s):  
Mechanical Properties ◽  
Sem Analysis ◽  
Composite Fibers ◽  
X Ray Diffraction ◽  
Natural Structure ◽  
Uniform Size ◽  
X Ray ◽  
Rheology Property ◽  
Crystallization Degree

The collagen was blended with polyvinyl alcohol (PVA) with the maximum maintenance of the natural structure as precondition. The apparent viscosity and rheology property of PVA-collagen blended solution were studied. the mechanical properties of the blend membrane formed from PVA-collagen blended solution were also determined. The PVA-collagen blended solution was wet spinned with the sodium sulfate as coagulant to prepare PVA-collagen composite fibers. SEM analysis and X-ray diffraction analysis of the PVA-collagen composite fibers were studied. The results indicated that, blended with PVA, the spinning property and mechanical properties of collagen were improved. The figure of the aim fiber transect structure was similar as the kidney, and it had a uniform size. The crystallization degree of the fiber was 55.7%, and it was increased with the increase of the hot extending temperature and the extending ratio.

Bioceramic Production from Giant Purple Barnacle (Megabalanus tintinnabulum)

2014 ◽  
Vol 631 ◽  
pp. 137-142 ◽  
Author(s):  
F.N. Oktar ◽  
H. Gokce ◽  
O. Gunduz ◽  
Y.M. Sahin ◽  
D. Agaogullari ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Complete Characterization ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Hot Plate ◽  
X Ray ◽  
Fine Powders ◽  
Simple Economic ◽  
And Chemical Properties

In this study the structural and chemical properties of barnacle shell based bioceramic materials (i.e. hydroxyapatite, whitlockite, monetite and other phases) were produced by using mechano-chemical (hot-plate) conversion method. Cleaned barnacle shells were ball milled down to <75µm in diameter. Differential thermal and gravimetric analyses (DTA/TGA) were performed to determine the exact CaCO3 content. Sample batches of 2g were prepared from the fine powders produced. For each batch, the required volume of an aqueous H3PO4 solution was calculated in order to set the stoichiometric molar ratio of Ca/P equal to 1.5 for ß-tricalcium phosphate (ß-TCP) or to 1.667 for hydroxyapatite (HA). The temperature was set to 80°C for 15 minutes to complete the process. After the titration of the equivalent amount of H3PO4 into the prepared solution, agitation was carried out on a hot-plate (i.e. mechano-chemical processing) for 8 hours. The sediments formed were dried and the resulting TCP and HA powders were calcined at 400°C and 800°C respectively. For complete characterization of the bioceramics produced, scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD) analyses were carried out. The current study proposes a simple, economic and time efficient method for nano-bioceramic production.

scholarly journals Synthesis and Characterization of Hydroxyapatite from Duck Eggshell by Wet Precipitation Process

2021 ◽  
Vol 3 (1) ◽  
pp. 8-11
Author(s):  
Yelmida Azis ◽  
Cory Dian Alfarisi ◽  
Komalasari Komalasari ◽  
Khairat Khairat ◽  
Yusnimar Sahan
Keyword(s):  
Xrd Analysis ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Precipitation Process ◽  
Stable Form ◽  
X Ray Diffraction ◽  
Precipitated Calcium Carbonate ◽  
X Ray ◽  
Inorganic Mineral

Hydroxyapatite (HAp, Ca10(PO4)6(OH)2) is the most stable form of calcium phosphate and widely used in various medical applications, mainly in orthopedics and dentistry due to its close similarities with the inorganic mineral component of bone and teeth. This study aims to synthesize hydroxyapatite from duck eggshell using the precipitation method. The duck eggshell was calcined, hydrated (slaking) and underwent carbonation to form Precipitated Calcium Carbonate (PCC).  Afterwards, (NH4)2HPO4 was added to produce HAp by varying the molar ratio of Ca/P by 1.67, 1.77 and 1.87 and stirring speed by 200, 250, 300rpm under basic condition (pH 10 – 11). The best results were obtained at a molar ratio of 1.77 with 200rpm stirring speed. Furthermore, the X-ray Diffraction (XRD) analysis showed that its crystals were hexagonal with sizes of 23.062nm, in the absence of other crystalline phases. Therefore, the hydroxyapatite was obtained in the agglomerates form with a specific surface area of ??55.929m2/g.

scholarly journals SYNTHESIS AND CHARACTERIZATION OF CALCIUM SILICATE FROM RICE HUSK ASH AND SNAIL SHELL

2019 ◽  
Vol 11 (2) ◽  
pp. 45
Author(s):  
Sadang Husain ◽  
Ninis Hadi Haryanti ◽  
Suryajaya Suryajaya ◽  
Antung Permitaria
Keyword(s):  
Rice Husk ◽  
Calcium Silicate ◽  
Rice Husk Ash ◽  
Wave Number ◽  
X Ray Diffraction ◽  
Solid Reaction ◽  
Snail Shell ◽  
X Ray ◽  
Infra Red

<p class="abstrak">Calcium silicate ceramics have been made using natural ingredients such as rice husk and snail shell with solid reaction techniques. The aim of this study to determine the characteristics of calcium silicate that have been sintered at a temperature of 900 <sup>°</sup>C, 1000 <sup>°</sup>C, and 1100 <sup>°</sup>C. Samples were characterized by X-Ray Diffraction (XRD), optical microscopy, and Fourier Transform Infra-Red (FTIR). The results of XRD characterization showed that CaSiO<sub>3</sub> (calcium silicate) along with the increase in calcination temperature and quantity was increased due to the increase of temperature of calcination. FTIR analysis showed that the Ca-Si-O bond was formed at wave number ranging from 848 cm<sup>-1</sup> and 999 – 1001 cm<sup>-1</sup>.</p>

scholarly journals Synthesis and Characterization of Zeolite X from Boiler Ash and Aluminum Foil Waste

2021 ◽  
Vol 4 (1) ◽  
pp. 15
Author(s):  
Intan Ayu Safitri ◽  
Iis Siti Jahro
Keyword(s):  
Aluminum Foil ◽  
Degree Of Crystallinity ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Zeolite X ◽  
X Ray ◽  
X Zeolite ◽  
Ft Ir ◽  
Boiler Ash

This study aims to determine the effect of the Si/Al molar ratio and the number of Na2EDTA additions on the purity and crystallinity levels of the synthesized zeolite X. zeolite X was synthesized by hydrothermal method at 70°C and 120°C for 3 and 6 hours, respectively. In the synthesis of zeolite X used boiler ash and aluminum foil waste. The results of characterization using Fourier Transform Infra Red (FT-IR) and X-Ray Diffraction (XRD) showed that the level of purity and crystallinity of the synthesized zeolite X was influenced by the variation of Si/Al molar rasio and amount of Na2EDTA addition. The zeolite with the best quality was obtained from the synthesis with a Si/Al molar ratio of 1.6 and the amount of Na2EDTA added as much as 3.0 g. The synthesized zeolite X has a purity level of 75% and a degree of crystallinity with a total intensity of 845.

Effect of expandable and expanded graphites on the thermo-mechanical properties of polyamide 11

2018 ◽  
Vol 51 (2) ◽  
pp. 175-190 ◽  
Author(s):  
F Oulmou ◽  
A Benhamida ◽  
A Dorigato ◽  
A Sola ◽  
M Messori ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Xrd Analysis ◽  
Crystal Form ◽  
X Ray Diffraction ◽  
Polyamide 11 ◽  
X Ray ◽  
Diffraction Peaks ◽  
Graphite Composites ◽  
And Storage

The preparation and thermo-mechanical characterization of composites based on polyamide 11 (PA11) filled with various amounts of both expandable and expanded graphites are presented. Investigation conducted using X-ray diffraction (XRD), scanning electron microscopy and surface area analyses indicated how graphite expanded under the selected processing conditions. The XRD analysis on PA11/graphite composites revealed no change in the crystal form of the PA11, while the presence of diffraction peaks associated to the graphite-stacked lamellae can be still detected. All the investigated composites showed an improvement of the thermal stability and mechanical properties (elastic and storage moduli).

scholarly journals Geomechanical characterization of lateritic hardpans from Bamendjou (West-Cameroon)

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Y. Ngueumdjo ◽  
V. H. Njuikom Djoumbi ◽  
V. Y. Katte ◽  
F. Ngapgue ◽  
A. S. L. Wouatong
Keyword(s):  
Mechanical Properties ◽  
Specific Gravity ◽  
Physical And Mechanical Properties ◽  
Western Region ◽  
Geochemical Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Geomechanical Characterization

AbstractThis study reports on the physical, mechanical, mineralogical and geochemical analysis carried out on four lateritic hardpan specimens from quarries in the Bamendjou area in the Western Region of Cameroon using common prescribed procedures. The results indicate that values of the bulk density, specific gravity, total and open porosities are very variable from one specimen to another. Meanwhile, the value of the compressive strengths of both the dry and immersed specimens were also very variable from one specimen to another, with the F2 and F1 specimens having higher values than the A1 and A2 specimens. All the specimens immersed in water recorded lower compressive strengths than the dry specimens. The flexural strengths also varied from one sample to another, with the F2 specimen having the highest resistance. The X-ray diffraction patterns reveal that the major peaks were assigned to gibbsite, goethite, and hematite, while the minor peaks were assigned to kaolinite and anatase. The mineralogy and geochemistry influenced the physical and mechanical properties, with the iron rich specimens having higher values in both the physical and mechanical properties than the alumina rich specimens. The results of the compressive strengths obtained were higher than (1–4) MPa obtained in Burkina Faso and India where they have been using latertic blocks for construction. Thus the hardpans of Bamendjou can also be exploited for building purposes conveniently.

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