scholarly journals The Use of Calcium Lactate to Enhance the Durability and Engineering Properties of Bioconcrete

2021 ◽  
Vol 13 (16) ◽  
pp. 9269
Author(s):  
Saddam Hussein Abo Sabah ◽  
Luis Hii Anneza ◽  
Mohd Irwan Juki ◽  
Hisham Alabduljabbar ◽  
Norzila Othman ◽  
...  
Keyword(s):  
Calcium Lactate ◽  
Engineering Properties ◽  
Optimal Conditions ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Sem Images ◽  
X Ray ◽  
Predicted Values ◽  
Potential Option ◽  
Scanning Electron

This study investigated the optimization of the bioconcrete engineering properties and durability as a response of the calcium lactate (CL) content (0.22–2.18 g/L) and curing duration (7–28 days) using the response surface methodology (RSM). Scanning electronic microscopy (SEM) was conducted to evaluate the microstructure of calcium precipitated inside the bioconcrete. The results indicated that the optimal conditions for the engineering properties of concrete and durability were determined at 2.18 g/L of CL content after 23.4 days. The actual and predicted values of the compressive strength, splitting tensile strength, flexural strength, and water absorption were 43.51 vs. 43.43, 3.19 vs. 3.19, 6.93 vs. 5.50, and 7.55 vs. 7.55, respectively, with a level of confidence exceeding 95%. The scanning electron microscope (SEM) images and energy-dispersive X-ray spectroscopy (EDX) proved that the amount of calcium increased with the increase in CL content up to 2.81 g/L at 23.4 days, reducing the pores inside the concrete and making it a great potential option for healing of concrete structures.

Miscibility Study of Chitosan and Methylcellulose Blends

2013 ◽  
Vol 750-752 ◽  
pp. 802-805 ◽  
Author(s):  
Peng Tao Liu ◽  
Xiang Mei Wei ◽  
Zhong Liu
Keyword(s):  
Thermogravimetric Analysis ◽  
Cross Sections ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Sem Images ◽  
X Ray ◽  
Ft Ir

The miscibility of chitosan / methylcellulose (CH/MC) blends was studied by FT IR, wide-angle X-ray diffraction (WAXD), thermogravimetric analysis (TGA), and scanning electronic microscopy (SEM). The regular changes of FT IR and WAXD spectra of CH/MC blend powder indicated the miscibility of the blends. TGA curves and SEM images of cross-sections of the blends films showed partly miscibility.

scholarly journals Effect of different cleansers on the surface of removable partial denture

2011 ◽  
Vol 22 (5) ◽  
pp. 392-397 ◽  
Author(s):  
Daniela Nair Borges Felipucci ◽  
Letícia Resende Davi ◽  
Helena Freitas Oliveira Paranhos ◽  
Osvaldo Luiz Bezzon ◽  
Rodrigo Ferreira Silva ◽  
...  
Keyword(s):  
Experimental Situation ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Sem Images ◽  
Removable Partial Denture ◽  
Partial Denture ◽  
X Ray ◽  
Eds Analysis ◽  
Chemical Solutions ◽  
Surface Changes

Removable partial dentures (RPD) demand specific hygienic cleaning and the combination of brushing with immersion in chemical solutions has been the most recommended method for control of biofilm. However, the effect of the cleansers on metallic components has not been widely investigated. This study evaluated the effect of different cleansers on the surface of RPD. Five disc specimens (12 mm x 3 mm metallic disc centered in a 38 x 18 x 4 mm mould filled with resin) were obtained for each experimental situation: 6 solutions [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) control] and 2 Co-Cr alloys [DeguDent (DD) and VeraPDI (VPDI)] were used for each experimental situation. A 180-day immersion was simulated and the measurements of roughness (Ra, µm) of metal and resin were analyzed using 2-way ANOVA and Tukey’s test. The surface changes and tarnishes were examined with a scanning electronic microscopy (SEM). In addition, energy dispersive x-ray spectrometry (EDS) analysis was carried out at representative areas. Visually, NaOCl and MI specimens presented surface tarnishes. The roughness of materials was not affected by the solutions (p>0.05). SEM images showed that NaOCl and MI provided surface changes. EDS analysis revealed the presence of oxygen for specimens in contact with both MI and NaOCl solutions, which might suggest that the two solutions promoted the oxidation of the surfaces, thus leading to spot corrosion. Within the limitations of this study, it may be concluded that the NaOCl and MI may not be suitable for cleaning of RPD.

scholarly journals Thermal Resistance Evaluation of Raffia Palm Ash Concrete

2021 ◽  
Vol 25 (3) ◽  
pp. 461-467
Author(s):  
U.N. Wilson ◽  
J.E. Sani ◽  
A.A. Adefila ◽  
I.S. Mohammed
Keyword(s):  
Electron Microscopy ◽  
Compressive Strength ◽  
Thermal Resistance ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Minimum Loss ◽  
X Ray ◽  
Average Loss ◽  
Sem Imaging ◽  
Scanning Electron

T: This research attempts to empirically investigate the behavior of Raffia Palm Ash (RPA) concrete under elevated temperature of different percentages of RPA inclusion in the concrete. Raffia palm ash was obtained after the calcination of the raffia palm for 3 hours at 5500C. X-ray Florescence (XRF) analysis performed revealed that the sample of Raffia Palm Ash (RPA) is a Class C pozzolana, which contains 51.8% of (SiO2 + Al2O3 + Fe2O3) and has a specific gravity of 2.8. The compressive strengths were determined at 0 0C, 718 0C and 821 0C at 0 minutes, 15 minutes and 30 minutes respectively. The result revealed that workability of the concrete declined with the increment in the percentage of raffia palm ash in the concrete. The compressive strength of the concrete cubes as well decreased with the rise in temperature for the entire samples tested. The average loss in strength of the control (0% RPA) is about 15.3% at 7180Cand 25.3% at 8120C while for Raffia palm ash concrete with 5% (optimum replacement) gives a minimum loss in strength of about 21.3% at 7180C and 28.5% at 8120C, which is about 6% at 7180C and 13.2% at 8120C, more than the control. The Scanning Electronic Microscopy (SEM) imaging indicates that the concrete subjected to temperature of about 821oC produces fewer flakes when compared to the concrete subjected to temperature of about 7180C. Keywords: Compressive strength, Raffia Palm Ash (RPA), Scanning Electron Microscopy (SEM), Thermal resistance, X-ray Florescence (XRF)

scholarly journals IMPROVEMENT OF MICROMERITIC, COMPRESSIBILITY AND SOLUBILITY CHARACTERISTICS OF LINEZOLID BY CRYSTALLO-CO-AGGLOMERATION TECHNIQUE

2017 ◽  
Vol 9 (4) ◽  
pp. 47 ◽  
Author(s):  
Atul M. Kadam ◽  
Shitalkumar S. Patil
Keyword(s):  
Drug Release ◽  
Methyl Cellulose ◽  
Mechanical Deformation ◽  
Angle Of Repose ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Fourier Transformation Infrared Spectroscopy ◽  
Time Required ◽  
Good Flow

Objective: The purpose of current study was to improve physicochemical properties such as micrometric, compressibility and solubility of linezolid (LNZ) by preparing crystallo-co-agglomerates (CCA) in the presence of polymer for the enhancement of overall physicochemical performance.Methods: The process of agglomeration involves the use of dichloromethane (DCM) as a good solvent and chloroform as bridging liquid were used to prepare agglomerates. Agglomerates were characterised in the solid state using several techniques such as Scanning electronic microscopy(SEM), Fourier transformation infrared spectroscopy (FTIR), X-ray powder diffraction analysis (XRPD) The agglomerates obtained were evaluated for micrometric, mechanical, deformation, compressibility and drug release properties.Results: It was found that micrometric properties and dissolution characteristics of agglomerates were significantly improved than that of pure linezolid. Solubility was found to be increased than pure linezolid. The solubility of crystallo co-agglomerates was found an increase in 5 fold 3 fold and 3.7 fold for PVPK30 (0.5%), PVPK30 (0.25%) and PVPK30 (0.75%) respectively. The angle of repose for all batches was found between 22 ° to 30 °Carrs index was between 12.27±0.6 to 18.73±0.4 and Hausners ratio Near to 1, indicated good flow ability of agglomerates. The time required for drug release over a period of 60 min, is as LA1>LA2>LA3. LA3 shows fast drug release than LA1 and LA2, due to solubilization of drug due to more concentration of PVPK30 and less concentration of talc.Conclusion: Based on the above results, it was revealed that CCA of linezolid prepared with DCM and HPMC (Hydroxypropyl methyl cellulose)/PEG (Polyethylene glycol)/PVP (Polyvinylpyrrolidone) K30 exhibited improved micrometric properties, compressibility and in addition to improving solubility and dissolution rate.

scholarly journals Applying Response Surface Methodology to optimize the decarbonization process of Timahdit oil shale

2019 ◽  
Vol 8 (5) ◽  
pp. 372-379 ◽  
Author(s):  
Laila Makouki ◽  
Meriem Tarbaoui ◽  
Samia Glissi ◽  
Said Mansouri ◽  
Hassan Hannache ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Acetic Acid ◽  
Response Surface ◽  
Oil Shale ◽  
Processing Time ◽  
Texture Evolution ◽  
Optimal Conditions ◽  
X Ray ◽  
Decarbonization Process ◽  
Scanning Electron

The present article aims to optimize the decarbonization of Timahdit oil shale layer Y by removing carbonates from the raw rock using acetic acid. The response surface methodology “central composite design (CCD)” has been used as a method of optimization to study the 3 factors of the process. The factors studied are the concentration of the acid, the processing time, and the ratio (liquid/solid). The optimal conditions with 68.17% of residue rate are obtained with 2 mol/l as concentration, 120 min as a time of treatment and 10.02 for the ratio.The raw (Y) and optimized materials (YO) were characterized by Scanning Electron Microscopy (SEM), X-ray fluorescence (XRF) and X-ray diffraction (XRD). The results showed that the acetic acid used to remove carbonates affects the chemical composition and the texture evolution of the residues.

Characterization of Shivirtui Zeolite Modified with Aluminum Oxyhydroxide Nanofibers

2019 ◽  
Vol 942 ◽  
pp. 40-49
Author(s):  
Yulia Murashkina ◽  
Olga B. Nazarenko
Keyword(s):  
Chemical Properties ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Aluminum Oxyhydroxide

Natural zeolite of Shivirtui deposit (Russia) was modified with nanofibers of aluminum oxyhydroxide AlOOH. Aluminum oxyhydroxide nanofibers were produced at the heating and oxidation of aluminum powder with water. The properties of modified zeolite were investigated by means of X-ray diffraction, transmission electronic microscopy, scanning electronic microscopy, low-temperature nitrogen adsorption, thermal analysis, and Fourier transform infrared spectroscopy. It was found that water content in the modified sample of zeolite was about 15 %. Based on the study of the physical and chemical properties, shivirtui zeolite modified with nanofibers of aluminum oxyhydroxide can be proposed for use as a flame-retardant additive to polymers.

The Competitive Growth of BiOI and BiSI in the Solvothermal Process

2011 ◽  
Vol 236-238 ◽  
pp. 1919-1922 ◽  
Author(s):  
Wen Jun Fa ◽  
Pin Jiang Li ◽  
Yan Ge Zhang ◽  
Li Li Guo ◽  
Jia Fan Guo ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Powder Diffraction ◽  
Energy Dispersive ◽  
Solvothermal Process ◽  
Competitive Growth ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray

BiOI nanolamellas and BiSI nanowires were synthesized using Bi(NO3)3·5H2O, (NH2)2CS and I2 as reactants in the solvothermal process with ethanol as the system media. The as-prepared samples were characterized by X-ray powder diffraction (XRD), scanning electronic microscopy (SEM), Energy-Dispersive X-ray Spectrometer (EDS). The competitive growth of BiOI and BiSI were investigated by changing the quantity of (NH2)2CS. A possible reaction mechanism was proposed.

scholarly journals Urea-Based Combustion Process for the Synthesis of Nanocrystalline Ni-La-Fe-O Catalysts

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Bahaa Abu-Zied ◽  
Abdullah M. Asiri
Keyword(s):  
Combustion Process ◽  
Catalytic Decomposition ◽  
Nitrogen Adsorption ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Hydrogen Peroxide Decomposition ◽  
Calcination Process ◽  
X Ray ◽  
Peroxide Decomposition ◽  
Combustion Route

Nanocrystalline Ni-La-Fe-O catalysts having the general formula NiLaxFe2−xO4(0.00≤x≤2.00) were synthesized by the combustion route employing urea as a combustion fuel. The calcination process was affected at 500°C. The structural properties of the obtained catalysts were systematically investigated by X-ray powder diffraction (XRD), scanning electronic microscopy (SEM), energy-dispersive X-ray spectra (EDX), and nitrogen adsorption at −196°C. Crystalline NiFe2O4and La2NiO4phases were detected for the catalysts havingx=0.00and 2.00, respectively, as a result of solid-solid interaction between mixtures precursors. The activity of the obtained catalysts was checked for hydrogen peroxide decomposition at 35–55°C. A synergic effect was observed for the catalysts havingx-value of 1.00 and 1.50. Such effect was attributed to the increase in the number of the active constituents involved in the catalytic decomposition of H2O2.

scholarly journals The Dehydrogenation Mechanism and Reversibility of LiBH4 Doped by Active Al Derived from AlH3

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 559 ◽  
Author(s):  
Qing He ◽  
Dongdong Zhu ◽  
Xiaocheng Wu ◽  
Duo Dong ◽  
Xiaoying Jiang ◽  
...  
Keyword(s):  
Reaction Products ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Scanning Calorimetry ◽  
Mass Spectral Analysis ◽  
X Ray ◽  
Mass Spectral ◽  
Al Composite ◽  
Dehydrogenation Mechanism

A detailed analysis of the dehydrogenation mechanism and reversibility of LiBH4 doped by as-derived Al (denoted Al*) from AlH3 was performed by thermogravimetry (TG), differential scanning calorimetry (DSC), mass spectral analysis (MS), powder X-ray diffraction (XRD), scanning electronic microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results show that the dehydrogenation of LiBH4/Al* is a five-step reaction: (1) LiBH4 + Al → LiH + AlB2 + “Li-Al-B-H” + B2H6 + H2; (2) the decomposition of “Li-Al-B-H” compounds liberating H2; (3) 2LiBH4 + Al → 2LiH + AlB2 + 3H2; (4) LiBH4 → LiH + B + 3/2H2; and (5) LiH + Al → LiAl + 1/2H2. Furthermore, the reversibility of the LiBH4/Al* composite is based on the following reaction: LiH + LiAl + AlB2 + 7/2H2 ↔ 2LiBH4 + 2Al. The extent of the dehydrogenation reaction between LiBH4 and Al* greatly depends on the precipitation and growth of reaction products (LiH, AlB2, and LiAl) on the surface of Al*. A passivation shell formed by these products on the Al* is the kinetic barrier to the dehydrogenation of the LiBH4/Al* composite.

Behavior of Scandium in Aluminum Alloys of Different Alloying Systems

2014 ◽  
Vol 794-796 ◽  
pp. 1002-1007
Author(s):  
Boris V. Ovsyannikov ◽  
Viktor M. Zamyatin
Keyword(s):  
Chemical Composition ◽  
Aluminum Alloys ◽  
Intermetallic Compounds ◽  
Alloy Composition ◽  
Alloying Elements ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Manganese Alloy ◽  
X Ray

Microstructure and composition of elements in phases of homogenized ingots in aluminum alloys of various alloying systems: Al-Mg-Mn-Si, Al-Mg-Si-Cu, and Al-Zn-Mg-Cu, were examined using a method of scanning electronic microscopy and X-ray microanalysis. Besides basic alloying elements of magnesium, zinc, copper, silicon, and manganese, alloy composition contained additional alloying elements, including zirconium and scandium. Presence of intermetallic compounds of various chemical composition insoluble during ingot homogenization was found in microstructure of examined samples. It is found that zirconium and scandium are jointly present in composition of some intermetallic compounds containing additional alloying elements of alloys.

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