Lebe A. Nnanna; Nkem B. Iroha
Abstract
The inhibiting effect of diphenoxylate drug (DD) on API X120 carbon steel corrosion in 15% HCl solution was investigated using chemical, electrochemical and surface morphological studies. The inhibition efficiency of the studied drug increases with increase in its concentrations, giving a maximum inhibition ...
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The inhibiting effect of diphenoxylate drug (DD) on API X120 carbon steel corrosion in 15% HCl solution was investigated using chemical, electrochemical and surface morphological studies. The inhibition efficiency of the studied drug increases with increase in its concentrations, giving a maximum inhibition efficiency of 95.28%, at the optimum concentration of 400 ppm. The effect of temperature revealed that the inhibition efficiency of DD decreases with temperature rise. The adsorption of DD obeyed the Langmuir isotherm and indicated predominantly physical adsorption mechanism. The electrochemical impedance spectroscopy (EIS) analysis affirmed the adsorption of the inhibitor on the X120 steel surface. Potentiodynamic polarization (PDP) study indicated that the tested drug acted as mixed type inhibitor with little anodic dominance. The result of scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy supported the formation of adsorbed inhibitor film on the X120 steel surface.
Shigehiro Hashimoto
Abstract
Biological cells adsorb on the scaffold, and show activities: migration, deformation, proliferation, and differentiation. The micro morphology (close to the cell size) on the surface of the scaffold (made by the photolithography technique) is effective for several applications: the marker to trace each ...
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Biological cells adsorb on the scaffold, and show activities: migration, deformation, proliferation, and differentiation. The micro morphology (close to the cell size) on the surface of the scaffold (made by the photolithography technique) is effective for several applications: the marker to trace each cell, and the tool to control the activity of each cell. C2C12 (mouse myoblast) is used in the present study. The typical diameter of the cell is 20 μm, when it is suspended in the medium. The cell aligns along the micro step of the height (> 0.7 μm). The micro-striped groove can control the cell orientation in the flow channel. The aspect ratio of the checkered convexo-concave pattern can control the orientation of cells. When cells are cultured on the thin film (thickness 6 μm, polydimethylsiloxane) with the micro markers at the counter surface, the local contraction movement of myotubes by the electrical-pulse stimulation can be microscopically measured through the transparent scaffold.
M. Belal Hossen; A.K.M. Akther Hossain
Abstract
The influence of Al 3+ substitution on the microstructure and impedance spectroscopy of Ni0.27Cu0.10Zn0.63AlxFe2-xO4 has been studied by scanning electron microscopy and impedance analyzer where the formation of the material in the spinel crystal structure was initially confirmed by X-ray structural ...
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The influence of Al 3+ substitution on the microstructure and impedance spectroscopy of Ni0.27Cu0.10Zn0.63AlxFe2-xO4 has been studied by scanning electron microscopy and impedance analyzer where the formation of the material in the spinel crystal structure was initially confirmed by X-ray structural analysis with room temperature data. The surface morphology indicates well defined grains separated by grain boundaries and with Al substitution average grain size decrease from 17 μm to 12 μm and zinc losses as well. The complex-plane impedance spectra indicate that the material can be represented by two semicircular arcs (its tendency) which corresponds to the bulk and the grain boundary resistance at high and low frequencies respectively. With Al substitution both grain and grain boundary resistance increases from 7.48 kΩ to 15.62 kΩ and 92.34 kΩ to 192.46 k respectively. Electric modulus spectra reflect the contributions from grain and grain boundary effects: the large resolved semicircle arc caused by the grain effect and the small poorly resolved semicircle arc was attributed to the grain boundary.
Richa Srivastava;B. C. Yadav
Abstract
Present paper deals with a comparative performance of n-type ZnO, ZnO-TiO2 and ZnO-Nb2O5 nanomaterials as humidity sensors. ZnO was synthesized through hydroxide route. TiO2 and then Nb2O5 were used as additives for improvement of sensitivity. Scanning electron micrograph of ZnO shows rod-like particles ...
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Present paper deals with a comparative performance of n-type ZnO, ZnO-TiO2 and ZnO-Nb2O5 nanomaterials as humidity sensors. ZnO was synthesized through hydroxide route. TiO2 and then Nb2O5 were used as additives for improvement of sensitivity. Scanning electron micrograph of ZnO shows rod-like particles with average diameter 40 nm. Structural properties by X-Ray diffraction were studied. The minimum crystallite sizes of ZnO-TiO2 and ZnO-Nb2O5 calculated from Scherrer’s formula were found to be 19 and 17 nm respectively. The pellet of each sensing material was annealed at temperatures 150, 300, 450 and 550 ?C for 3 h and checked for its sensing efficiency. Each heat treated pellet was exposed to humidity under controlled condition and variations in resistance with the humidity were recorded. Comparative study of sensitivities of each sensing element was performed. Average sensitivity achieved was 8 MΩ/%RH for the n-type ZnO annealed at 550 ?C. After chemical mixing of TiO2, the sensitivity increased to 18 MΩ/%RH and after Nb2O5, it was found to be 19 MΩ/%RH. Activation energy of electrical transport and Kelvin radii of each sensing elements were also studied.
Satyendra Singh; B. C. Yadav; Archana Singh; Prabhat K. Dwivedi
Abstract
In this paper we report the synthesis of iron-antimonate (FeSbO4) via co-precipitation method for the LPG sensing application. X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray analysis (EDAX) were used to confirm the crystal structure, crystallite size, surface ...
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In this paper we report the synthesis of iron-antimonate (FeSbO4) via co-precipitation method for the LPG sensing application. X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray analysis (EDAX) were used to confirm the crystal structure, crystallite size, surface morphology and elemental composition of the sensing material. Our XRD results confirm the single phase formation with tetragonal crystal structure of the synthesized material. Extremely broad reflections were observed indicating nanosized particle nature of the material obtained. The estimated value of average crystallite size was found 3 nm. Optical characterizations were done using UV-visible spectrophotometer and the value of energy band gap was found 3.8 eV by Tauc plot. Fine powder resulted from the chemical co-precipitation reaction was used to prepare the LPG sensing element in the form of pellet. The average sensor response of the FeSbO4 pellet was 2.2. LPG sensor based on iron-antimonate shows 97% reproducibility after one month, which illustrates the stability of the fabricated sensor. Electrical properties of iron-antimonate in air were also investigated.
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