scholarly journals Swelling of Natural Soil Subjected to Acidic and Alkaline Contamination

2017 ◽  
Author(s):  
Hariprasad Reddy Ponnapureddy ◽  
Rama Vara Prasad Chavali ◽  
Rakesh J Pillai
Keyword(s):  
Electron Microscopy ◽  
Sodium Hydroxide ◽  
Sodium Hydroxide Solution ◽  
Expansive Soil ◽  
Natural Soil ◽  
Acid Solutions ◽  
One Dimensional ◽  
X Ray ◽  
Free Swell ◽  
Scanning Electron

This paper aims at establishing the influence of acidic and alkalinepore fluids on the swell behaviour of an expansive soil. Aseries of laboratory one dimensional free swell tests were performedto study the behaviour of soil in acidic and alkaline environment.Three different concentrations of sodium hydroxide andsulphuric acid solutions were used as pore fluids to understandthe influence of variable concentrations on the swell behaviourof soil. Results showed that, the swelling of soil that interactedwith sodium hydroxide solution initially increased at lower concentrationand then decreased with increase in concentration.In contrast, the swelling initially decreased at lower concentrationof sulphuric acid and then increased with increase inconcentration of solution. The complexity in the swell behaviourof contaminated soil was assessed by thoroughly investigatingthe mineralogy and microstructure alterations by carrying outX-ray diffraction analysis, Scanning electron microscopy andEnergy dispersive analysis of X-ray at the end of interaction.

The adsorption of methylene blue on montmorillonite from acid solutions

Clay Minerals ◽  
2011 ◽  
Vol 46 (3) ◽  
pp. 461-471 ◽  
Author(s):  
Z. Klika ◽  
P. Pustková ◽  
M. Dudová ◽  
P. Čapková ◽  
Ch. Kliková ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Methylene Blue ◽  
Ion Exchange ◽  
Powder Diffraction ◽  
Acid Solutions ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Adsorption Wave ◽  
Scanning Electron

AbstractThe adsorption of methylene blue (MB) on montmorillonite from acid solutions has not yet been studied in detail. In this paper the adsorption of this dye on Ca/SAz montmorillonite from 0.32, 0.80 and 1.60 M HCl solutions at ambient temperature and after 2 hours leaching was carefully studied and evaluated. Under the above conditions the MB/SAz intercalates formed are practically insoluble. In contrast to the adsorption of methylene blue on montmorillonite from aqueous solutions, the adsorption from acid solutions consists of two adsorption waves. The intercalated samples from the first and second waves were studied using X-ray powder diffraction (XRD), FTIR, Vis spectroscopy, and scanning electron microscopy (SEM) equipped with a microprobe system. The adsorption of MB in the first wave is attributed to ion exchange of the dye cationic species (MB+, MB22+, H-aggregates, MBH2+ and H+) for the original interlayer cations of montmorillonite. The percentages of MBH2+ and H+ based on total adsorbed MB were estimated for varying HCl concentrations. The second adsorption wave is linked to the precipitation of MB species on the outer MB/SAz surface.

Dicyclohexylammonium bromoacetate: a low molecular mass organogelator with a one-dimensional secondary ammonium monocarboxylate (SAM) synthon

2015 ◽  
Vol 71 (7) ◽  
pp. 593-597 ◽  
Author(s):  
Tomasz Rojek ◽  
Tadeusz Lis ◽  
Ewa Matczak-Jon
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Hydrogen Bond ◽  
Ion Pairs ◽  
Asymmetric Unit ◽  
One Dimensional ◽  
X Ray ◽  
H Nmr ◽  
Ft Ir ◽  
Scanning Electron

The asymmetric unit of the title salt, C12H24N+·C2H2BrO2−, contains a dicyclohexylammonium cation connected to a bromoacetate anion by means of an N—H...O hydrogen bond. In the crystal, the ion pairs assembleviaN—H...O interactions, forming zigzag infinite chains parallel to thecaxis with the (...H—N—H...O—C—O...)nmotif that is considered to be a prerequisite for ensuring gelation properties of secondary ammonium monocarboxylate salts. The title salt was characterized by FT–IR, X-ray powder diffraction (XRPD), TG–DTA and1H NMR spectroscopy in solution. Gelation experiments revealed that dicyclohexylammonium bromoacetate forms molecular gels with dimethylformamide and dimethyl sulfoxide. Scanning electron microscopy (SEM) was used to reveal morphological features of dried gels.

The effect of calcination temperature on metakaolin structure for the synthesis of zeolites

Clay Minerals ◽  
2018 ◽  
Vol 53 (4) ◽  
pp. 657-663 ◽  
Author(s):  
Magdalena Król ◽  
Piotr Rożek
Keyword(s):  
Electron Microscopy ◽  
Sodium Hydroxide Solution ◽  
Alkali Activation ◽  
Zeolite A ◽  
Optimal Temperature ◽  
X Ray Diffraction ◽  
Activation Temperature ◽  
X Ray ◽  
Naoh Solution ◽  
Scanning Electron

ABSTRACTThe aim of this research was to determine the temperature of kaolin calcination in order to obtain an intermediate product (metakaolin) for the synthesis of geopolymers with potential application as self-supporting zeolitic membranes. The products obtained were analysed with X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The structural analysis of the metakaolins obtained suggested that the optimal temperature for the proposed application is 700°C. After alkali activation of metakaolin, it is possible to obtain zeolite A and hydroxysodalite. The factors analysed, determining the type and quantity of crystalline phases, were activation temperature and concentration of sodium hydroxide solution (activator). The largest amounts of zeolites were obtained by alkali activation with 9 mol/dm3 NaOH solution at 70°C.

Features of pore formation of semiconductors by example zinc selenide and indium phosphide

2012 ◽  
Vol 16 (5) ◽  
pp. 13-17
Author(s):  
V.V. Kidalov ◽  
O.V. Marakhovskyi ◽  
Ya.O. Cychikova ◽  
H.O. Sukach
Keyword(s):  
Electron Microscopy ◽  
Indium Phosphide ◽  
Zinc Selenide ◽  
Pore Formation ◽  
Acid Solutions ◽  
Analysis Method ◽  
X Ray ◽  
Porous Layers ◽  
Inp Substrates ◽  
Scanning Electron

The paper represent a methodology and mechanizm of obtaining porous layers in ZnSe and InP substrates by photoelectochemical etching in acid solutions. Morphology of the surface was investigated by using scanning electron microscopy. By using energy dispersion X-ray analysis method (EDAX) was determined chemical composition of the obtained film`s surface

Electrochemical Characteristics of the Amorphous-Nanocrystal Ni–Mo Cathodes in Sodium Hydroxide Solution

2015 ◽  
Vol 667 ◽  
pp. 280-285
Author(s):  
Ning Li ◽  
Jian Meng Huang ◽  
Wei Zeng Chen ◽  
Bin Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Hydrogen Evolution ◽  
Sodium Hydroxide Solution ◽  
Electrochemical Characteristics ◽  
Phase Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
Modern Technologies ◽  
Scanning Electron

The amorphous-nanocrystal Ni-Mo deposits were obtained by electrodeposition in alkaline nickel carbonate solution. X-ray diffraction (XRD), scanning electron microscopy (SEM) and modern technologies were used to describe the content, microstructure and morphology of the deposits. The electrochemical characteristics of Ni-Mo deposits were electrolyzed in 33°C, 7 mol/L NaOH electrolytic solutions. The results showed that when I was 100 mA·cm−2, the hydrogen evolution potential of Ni-Mo21.76 was lower than amorphous Ni-Mo26.36 and 250mV lower than the nanocrystal Ni cathode. And the Ni-Mo deposits with more amorphous phase content would be in lower hydrogen evolution overpotential, a higher exchange current density, and a better electrolytic stability. These due to the amorphous combined with nanocrystal, lager contact surface and binding energy of Ni-Mo structure.

scholarly journals Enhanced Electrorheological Response of Cellulose: A Double Effect of Modification by Urea-Terminated Silane

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 867 ◽  
Author(s):  
Zhao Liu ◽  
Panpan Chen ◽  
Xiao Jin ◽  
Li-Min Wang ◽  
Ying Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silicone Oil ◽  
Sodium Hydroxide Solution ◽  
Double Effect ◽  
Natural Polymer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Modified Cellulose ◽  
Scanning Electron

As a natural polymer with abundant sources, cellulose was one of the earliest applied electrorheological (ER) materials. However, cellulose-based ER materials have not attracted much attention because of their relatively low ER effect and sensitivity to water. In this study, cellulose rods were decorated with a urea-terminated silane, 1-(3-(trimethoxysilyl) propyl) urea, after being swelled in sodium hydroxide solution. The morphologies and structures of the cellulose particles were investigated using scanning electron microscopy, Fourier-transform infrared spectroscopy and X-ray diffraction, confirming the dramatic differences of the treated cellulose particles from the pristine cellulose. Rheological behaviors of the pristine and modified cellulose particles in silicone oil were observed using a rotational rheometer. It was found that the silane-modified cellulose showed higher ER effect and higher dielectric properties than the pristine cellulose particles, which was not only related to the grafted polar molecules but may also be associated with the porous morphologies of the treated cellulose particles.

Synthesis and Properties of GaN Nanostructures

2005 ◽  
Vol 475-479 ◽  
pp. 3367-3370
Author(s):  
Hong-Lei Ma ◽  
Cheng Shan Xue ◽  
Ying Ge Yang ◽  
Hui Zhao Zhang ◽  
Jin Ma ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Hexagonal Wurtzite Structure ◽  
X Ray Diffraction ◽  
High Quality ◽  
One Dimensional ◽  
X Ray ◽  
Gan Nanowires ◽  
Transmission Electron ◽  
Morphology And Structure ◽  
Scanning Electron

One-dimensional GaN nanostructure films were successfully synthesized by the recently developed sputtering post-nitridation technique. The morphology and structure of GaN nanowires are investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results indicate that the crystalline GaN nanostructures have a hexagonal wurtzite structure, and there is not any other phase such as Ga2O3 or Ga in the specimen. It also confirms that high quality crystal was obtained in the resulting sample due to the lattice defects decreased and the crystallinity improved in the process of nitridation at high temperature. The growth mechanism of the GaN nanostructures is briefly discussed.

Surface micro-dissolve treatment of cotton fabrics with sodium hydroxide/urea to impart crease-resistance properties

2017 ◽  
Vol 88 (14) ◽  
pp. 1671-1676 ◽  
Author(s):  
Ming Lu ◽  
Ruimin Hu ◽  
Zhenyun Zhao ◽  
Jing Zhou ◽  
Yiping Liu
Keyword(s):  
Electron Microscopy ◽  
Sodium Hydroxide ◽  
Breaking Strength ◽  
Moisture Sorption ◽  
Cotton Fabrics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cellulose Solvent ◽  
Tearing Strength ◽  
Scanning Electron

In this study, cotton fabric samples were treated by the surface micro-dissolve process to improve their crease-resistance properties. The surface micro-dissolve treatment was conducted in the presence of sodium hydroxide/urea as an effective cellulose solvent at low temperature. The treated cotton fabrics were characterized by scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. Crease-resistance, tearing strength, breaking strength, whiteness degrees and moisture sorption values of the fabrics were also studied. The results indicated that the surface micro-dissolve treatment could effectively improve the crease-resistance properties of cotton fabrics. Moreover, the mechanical properties and whiteness degrees of fabric samples were retained well.

scholarly journals Control of the Morphology of Molybdenum Dioxide Nanoparticles

2012 ◽  
Vol 9 (1) ◽  
pp. 233-239 ◽  
Author(s):  
R. Naouel ◽  
F. Touati ◽  
N. Gharbi
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Hydrothermal Process ◽  
X Ray Diffraction ◽  
Molybdenum Dioxide ◽  
One Dimensional ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Synthesis of MoO2nanoparticles with one-dimensional (1D) and spherical morphologies in aqueous solutions, through hydrothermal process was investigated. The materials were studied by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Infrared spectroscopy (FTIR) and thermal analysis (TG). It was found that the quantity of organic compound influenced the size and shape of the final product. The possible formation mechanism of MoO2microspheres and nanowires was also discussed. The conductivity of MoO2nanowires was explained by the presence of two protons types in the material.

scholarly journals Synthesis of nanocomposites based on strontium stannate

2021 ◽  
Vol 340 ◽  
pp. 01049
Author(s):  
Anton Loginov ◽  
Alexandr Aparnev
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Acid Solutions ◽  
X Ray Diffraction ◽  
Decomposition Products ◽  
X Ray ◽  
Hydrochloric Acid Solutions ◽  
Strontium Stannate ◽  
Double Hydroxide ◽  
Scanning Electron

From hydrochloric acid solutions of strontium and tin(IV) by addition of ammonia until pH = 10 was obtained double hydroxide of strontium-tin(IV) SrSn(OH)6. The process of double hydroxide thermolysis and the phase composition of decomposition products were studied by differential thermal analysis, X-ray diffraction and scanning electron microscopy. It is shown that the main dehydration step is completed at a temperatureofnearly350°CandX-rayamorphousproductisformed which converts into the crystalline phase of strontium stannate at a temperature above 650°C.

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