97/01380 Sintering and fouling characterization of ashes with high calcium oxide content

1997 ◽  
Vol 38 (2) ◽  
pp. 108
Keyword(s):  
Calcium Oxide ◽  
Oxide Content ◽  
High Calcium

Production of Biodiesel from Palm Stearin Using Solid Catalyst Assisted with Co-Solvent

2018 ◽  
Vol 876 ◽  
pp. 9-14 ◽  
Author(s):  
Weerasak Songoen ◽  
Vittaya Punsuvon ◽  
Wallop Arirop ◽  
Athitan Timyamprasert
Keyword(s):  
Calcium Oxide ◽  
Palm Stearin ◽  
Biodiesel Production ◽  
Proton Nuclear Magnetic Resonance ◽  
Solid Catalyst ◽  
Resonance Spectroscopy ◽  
Oxide Content ◽  
Optimum Conditions ◽  
Quick Lime ◽  
High Calcium

Calcium methoxide obtained from quick lime is used as a solid catalyst in the transesterification reaction between palm stearin with methanol using tetrahydrofuran (THF) as co-solvent for biodiesel production. In this work, quick lime was used to prepare calcium oxide by heat treatment at the different temperatures, after that calcium oxide was further reacted with methanol to produce calcium methoxide catalyst. The properties of Calcium methoxide (Ca(OCH3)2) was characterized by XRD, SEM, BET, TGA, EDX and FTIR. The optimum conditions of biodiesel production were studied through response surface methodology and central composite design. The conversion of fatty acid methyl ester (FAME) was determined by proton nuclear magnetic resonance spectroscopy (1H-NMR). The results depicted that calcined quick lime at 800 °C for 3 h contained high calcium oxide content. The Ca(OCH3)2 catalyst prepared at 65 °C for 3 h gave high surface area and catalytic activity. The optimum conditions for biodiesel production were 2.33% w/w of catalyst, 1 : 9.39 of palm stearin to methanol molar ratio, 102 min of reaction time and 9.07% v/v based on methanol of THF co-solvent, the same condition gave 98.23% of FAME conversion.

Preparation and characterization of calcium oxide nanoparticles from marine molluscan shell waste as nutrient source for plant growth

2021 ◽  
Author(s):  
Kabali Vijai Anand ◽  
Munuswamy Reshma ◽  
Malaichamy Kannan ◽  
Sekaran Muthamil Selvan ◽  
Sumit Chaturvedi ◽  
...  
Keyword(s):  
Plant Growth ◽  
Calcium Oxide ◽  
Oxide Nanoparticles ◽  
Nutrient Source ◽  
Molluscan Shell ◽  
Shell Waste

scholarly journals Mineralogical and Microstructure Analysis for Characterization and Provenance of Ceramic Artifacts from Late Helladic Kastrouli Settlement, Delphi (Central Greece)

Geosciences ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 36
Author(s):  
Vayia Xanthopoulou ◽  
Ioannis Iliopoulos ◽  
Ioannis Liritzis
Keyword(s):  
Raw Materials ◽  
Analytical Techniques ◽  
Sem Analysis ◽  
Petrographic Analysis ◽  
Ceramic Assemblage ◽  
Thin Sections ◽  
Central Greece ◽  
High Calcium ◽  
Local Geology

The present study deals with the characterization of a ceramic assemblage from the Late Mycenaean (Late Helladic III) settlement of Kastrouli, at Desfina near Delphi, Central Greece using various analytical techniques. Kastrouli is located in a strategic position supervising the Mesokampos plateau and the entire peninsula and is related to other nearby coeval settlements. In total 40 ceramic sherds and 8 clay raw materials were analyzed through mineralogical, petrographic and microstructural techniques. Experimental briquettes (DS) made from clayey raw materials collected in the vicinity of Kastrouli, were fired under temperatures (900 and 1050 °C) in oxidizing conditions for comparison with the ancient ceramics. The petrographic analysis performed on thin sections prepared from the sherds has permitted the identification of six main fabric groups and a couple of loners. The aplastic inclusions recognized in all fabric groups but one confirmed the local provenance since they are related to the local geology. Fresh fractures of representative sherds were further examined under a scanning electron microscope (SEM/EDS) helping us to classify them into calcareous (CaO > 6%) and non-calcareous (CaO < 6%) samples (low and high calcium was noted in earlier pXRF data). Here, the ceramic sherds with broad calcium separation are explored on a one-to-one comparison on the basis of detailed mineralogical microstructure. Moreover, their microstructure was studied, aiming to estimate their vitrification stage. The mineralogy of all studied samples was determined by means of X-ray powder diffraction (XRPD), permitting us to test the validity of the firing temperatures revealed by the SEM analysis. The results obtained through the various analytical techniques employed are jointly assessed in order to reveal potters’ technological choices.

scholarly journals Immortalization and Characterization of Rat Lingual Keratinocytes in a High-Calcium and Feeder-Free Culture System Using ROCK Inhibitor Y-27632

2021 ◽  
Vol 22 (13) ◽  
pp. 6782
Author(s):  
Zixing Chen ◽  
Wenmeng He ◽  
Thomas Chun Ning Leung ◽  
Hau Yin Chung
Keyword(s):  
Calcium Imaging ◽  
Cultured Cells ◽  
Rho Kinase ◽  
Culture Method ◽  
Taste Bud ◽  
Label Free ◽  
Sprague Dawley ◽  
Rock Inhibitor ◽  
High Calcium

Cultured keratinocytes are desirable models for biological and medical studies. However, primary keratinocytes are difficult to maintain, and there has been little research on lingual keratinocyte culture. Here, we investigated the effect of Y-27632, a Rho kinase (ROCK) inhibitor, on the immortalization and characterization of cultured rat lingual keratinocyte (RLKs). Three Y-27632–supplemented media were screened for the cultivation of RLKs isolated from Sprague–Dawley rats. Phalloidin staining and TUNEL assay were applied to visualize cytoskeleton dynamics and cell apoptosis following Y-27632 removal. Label-free proteomics, RT-PCR, calcium imaging, and cytogenetic studies were conducted to characterize the cultured cells. Results showed that RLKs could be conditionally immortalized in a high-calcium medium in the absence of feeder cells, although they did not exhibit normal karyotypes. The removal of Y-27632 from the culture medium led to reversible cytoskeletal reorganization and nuclear enlargement without triggering apoptosis, and a total of 239 differentially expressed proteins were identified by proteomic analysis. Notably, RLKs derived from the non-taste epithelium expressed some molecular markers characteristic of taste bud cells, yet calcium imaging revealed that they rarely responded to tastants. Collectively, we established a high-calcium and feeder-free culture method for the long-term maintenance of RLKs. Our results shed some new light on the immortalization and differentiation of lingual keratinocytes.

scholarly journals Characterization of calcium oxide in root perforation sealer materials

2012 ◽  
Vol 23 (5) ◽  
pp. 539-546 ◽  
Author(s):  
Carlos Estrela ◽  
Manoel Damião Sousa-Neto ◽  
Orlando Aguirre Guedes ◽  
Ana Helena Gonçalves Alencar ◽  
Marco Antonio Hungaro Duarte ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Mineral Trioxide Aggregate ◽  
Chemical Compounds ◽  
Internal Diameter ◽  
X Ray ◽  
Final Sample ◽  
Materials Used ◽  
Main Components ◽  
White Mineral

Root perforation represents an undesirable complication that may lead to an unfavorable prognosis. The aims of this study were to characterize and to compare the presence of calcium oxide (CaO) on the chemical composition of materials used for root perforation therapy: gray and white mineral trioxide aggregate (MTA) and Portland cement (PC), gray MTA+5%CaO and gray MTA+10%CaO. The last two materials were analyzed to evaluate the increase of CaO in the final sample. CaO alone was used as a standard. Eighteen polyethylene tubes with an internal diameter of 3 mm and 3 mm in length were prepared, filled and then transferred to a chamber with 95% relative humidity and a temperature of 37ºC. The chemical compounds (particularly CaO) and the main components were analyzed by energy-dispersive X-ray microanalysis (EDX). EDX revealed the following concentrations of CaO: gray MTA: 59.28%, white MTA: 63.09%; PC: 72.51%; gray MTA+5%CaO: 63.48% and gray MTA+10%CaO: 67.55%. The tested materials presented different concentrations of CaO. Even with an increase of 5 and 10% CaO in gray MTA, the CaO levels found in the MTA samples were lower than those found in PC.

FT-IR and micro-Raman spectroscopic characterization of minerals in high-calcium coal ashes

2018 ◽  
Vol 91 (3) ◽  
pp. 389-396 ◽  
Author(s):  
Yanshan Yin ◽  
Jie Yin ◽  
Wei Zhang ◽  
Hong Tian ◽  
Zhangmao Hu ◽  
...  
Keyword(s):  
Spectroscopic Characterization ◽  
Raman Spectroscopic ◽  
High Calcium ◽  
Ft Ir ◽  
Coal Ashes

Characterization of calcium oxide catalysts from natural sources and their application in the transesterification of sunflower oil

2014 ◽  
Vol 151 ◽  
pp. 207-213 ◽  
Author(s):  
Leandro Marques Correia ◽  
Rosana Maria Alves Saboya ◽  
Natália de Sousa Campelo ◽  
Juan Antonio Cecilia ◽  
Enrique Rodríguez-Castellón ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Sunflower Oil ◽  
Oxide Catalysts ◽  
Natural Sources

scholarly journals Characterization of the Physical, Chemical, and Adsorption Properties of Coal-Fly-Ash–Hydroxyapatite Composites

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 774
Author(s):  
Eleonora Sočo ◽  
Dorota Papciak ◽  
Magdalena M. Michel ◽  
Dariusz Pająk ◽  
Andżelika Domoń ◽  
...  
Keyword(s):  
Fly Ash ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Synthesis Conditions ◽  
High Calcium ◽  
Ft Ir ◽  
Ir Analysis ◽  
Wet Synthesis

(1) Hydroxyapatite (Hap), which can be obtained by several methods, is known to be a good adsorbent. Coal fly ash (CFA) is a commonly reused byproduct also used in environmental applications as an adsorbent. We sought to answer the following question: Can CFA be included in the method of Hap wet synthesis to produce a composite capable of adsorbing both heavy metals and dyes? (2) High calcium lignite CFA from the thermal power plant in Bełchatów (Poland) was used as the base to prepare CFA–Hap composites. Four types designated CFA–Hap1–4 were synthesized via the wet method of in situ precipitation. The synthesis conditions differed in terms of the calcium reactants used, pH, and temperature. We also investigated the equilibrium adsorption of Cu(II) and rhodamine B (RB) on CFA–Hap1–4. The data were fitted using the Langmuir, Freundlich, and Redlich–Peterson models and validated using R2 and χ2/DoF. Surface changes in CFA–Hap2 following Cu(II) and RB adsorption were assessed using SEM, SE, and FT-IR analysis. (3) The obtained composites contained hydroxyapatite (Ca/P 1.67) and aluminosilicates. The mode of Cu(II) and RB adsorption could be explained by the Redlich–Peterson model. The CFA–Hap2 obtained using CFA, Ca(NO3)2, and (NH4)2HPO4 at RT and pH 11 exhibited the highest maximal adsorption capacity: 73.6 mg Cu/g and 87.0 mg RB/g. (4) The clear advantage of chemisorption over physisorption was indicated by the Cu(II)–CFA–Hap system. The RB molecules present in the form of uncharged lactone were favorably adsorbed even on strongly deprotonated CFA–Hap surfaces.

Electrokinetic Phenomena and Surface Characteristics of Fly Ash Particles

1984 ◽  
Vol 43 ◽  
Author(s):  
R. I. A. Malek ◽  
D. M. Roy
Keyword(s):  
Fly Ash ◽  
Surface Characteristics ◽  
Ionic Species ◽  
Point Of Zero Charge ◽  
Fly Ashes ◽  
Electrokinetic Phenomena ◽  
Zeta Potentials ◽  
Low Calcium ◽  
High Calcium

AbstractThe zeta-potentials of two fly ashes were studied (high-calcium and low-calcium). It was found that they possess a point of charge reversal at pH = 10.5 to 12. The point of zero charge (low-calcium fly ash) was found to be at pH = 5. Furthermore, it shifted to more acidic values after the fly ash is aged in several calcium-containing solutions. The surficial changes that could happen when mixing fly ashes with cement and concrete were further evaluated by aging fly ashes in different solutions: Ca(OH)2, CaSO4·2H2O, NaOH and water solutions. Information from analyses for different ionic species in the solutions and characterization of the solid residues (XRD and SEM) was used in tentative explanations for the different behavior of the two types of fly ash in cementitious mixtures and concrete.

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