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101.
The corrosion inhibition effect of cationic surfactants, DTAB (Dodecyl Trimethyl Ammonium Bromide) and TTAB (Tetradecyl Trimethyl Ammonium Bromide), on low carbon steel was studied using weight loss, open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements. The effect of chain length compatibility on corrosion inhabitancy of surfactant and co-surfactant was investigated by C7OH (1-heptanol), C12OH (1-dodecanol) and C15OH (1-pentadecanol) as nonionic co-surfactants in acidic media at different concentrations of DTAB and TTAB. Data represented that the corrosion rate decreased by increasing concentration of DTAB and TTAB, independently. The effect of chain length compatibility on surfactant behavior was discussed. Decreasing of corrosion rate for DTAB + C12OH was more pronounced than other mixtures.  相似文献   
102.
Summary The rotating flow of a third-grade fluid on an oscillating porous plate in the presence of a transverse magnetic field is considered. An analytic solution of the governing nonlinear boundary layer equation is obtained. Expressions for the velocity profile are established. It is found that an external magnetic field has the same effect on the flow as the material parameters of the fluid. Further the symmetric and asymmetric nature of the solutions is discussed.  相似文献   
103.
The present work deals with the development of a new ternary composite, \(\hbox {Ag}_{2}\hbox {Se}\)\(\hbox {G}\)\(\hbox {TiO}_{2}\), using ultrasonic techniques as well as X-ray diffraction (XRD), scanning electron microscopy (SEM), high transmission electron microscopy (HTEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and UV–Vis diffuse reflectance spectra (DRS) analyses. The photocatalytic potential of nanocomposites is examined for \(\hbox {CO}_{2}\) reduction to methanol under ultraviolet (UV) and visible light irradiation. \(\hbox {Ag}_{2}\hbox {Se}\)\(\hbox {TiO}_{2}\) with an optimum loading graphene of 10 wt% exhibited the maximum photoactivity, obtaining a total \(\hbox {CH}_{3}\hbox {OH}\) yield of 3.52 \(\upmu \hbox {mol}\,\hbox {g}^{-1}\,\hbox {h}^{-1}\) after 48 h. This outstanding photoreduction activity is due to the positive synergistic relation between \(\hbox {Ag}_{2}\hbox {Se}\) and graphene components in our heterogeneous system.  相似文献   
104.
Neural Computing and Applications - Harris hawks optimizer (HHO) has received widespread attention among researchers in terms of the performance, quality of results, and its acceptable convergence...  相似文献   
105.
The tensile creep behavior of extruded Mg-6 Gd alloy,having the tensile yield strength of~ 110 MPa at 175 ℃,has been investigated under 175 ℃ and 150 MPa. In this study, the extruded Mg-6 Gd sample exhibits the total tensile strain of ~10.5% after the creep time of 1100 h,and the fast plastic strain of ~4.6% at the beginning of the creep test. The microstructure result suggests that the dislocation deformation is the main deformation mode during creep, and the grains with orientation close to(0001) II ED disappear after creep. The creep process containing a low creep strain has no effective promotion for the precipitation compared with the aging process without strain. The origination of creep crack is related to the formation of precipitate-free zone during creep. The work offers an important implication to research the microstructure evolution under an applied stress in a weak aging response Mg alloy.  相似文献   
106.
Although ceramic nanocomposite fuel cells (CNFCs) have attracted the attention of the fuel cell community due to their low operating temperature (<600 °C), often the performance of the cells is limited due to the low ionic conductivity of the electrolyte and the sluggish reaction kinetics at the electrodes. This results in high ohmic and charge transfer losses in the cell performance. Here we report nanocomposite electrolyte (GDC-NLC) and electrodes (NiO-GDC-NLC and LSCF-GDC-NLC as anode and cathode respectively) with enhanced ionic conductivity and catalytic activity respectively, which significantly improve the ionic transport in the electrolyte layer (ohmic losses ≈ 0.23 Ω cm2) and the reaction kinetics at the electrodes (polarization losses ≈ 0.63 Ω cm2). Microstructural and phase changes in the materials were characterized with X-ray diffraction, scanning electron microscopy, and differential scanning calorimetry to understand the mechanisms in the cells. Our button fuel cell produced an outstanding performance of 1.02 W/cm2 at 550 °C.  相似文献   
107.
International Journal of Control, Automation and Systems - Optimal path planning for three or more unmanned aerial vehicles (UAVs) in radio source localization has been studied extensively; but...  相似文献   
108.
In this study, I investigated some of the cognitive and affective causes of interest and liking. In Experiment 1, 240 undergraduates read stories with endings that varied in the degree of surprise, outcome valence (i.e., goodness or badness of outcome), and incongruity resolution. The results did not support the hypothesis that degree of surprise per se causes interest (Schank, 1979). Instead, as suggested by Kintsch (1980), subjects rated high-surprise story endings as more interesting than low-surprise story endings for those conditions in which the postsurprise incongruity was resolved (p?p?  相似文献   
109.
Summary Exact analytic solutions for the flow of non-Newtonian fluid generated by periodic oscillations of a rigid plate are discussed. Some interesting flows caused by certain special oscillations are also obtained.  相似文献   
110.
A single‐step deposition of cobalt‐doped zinc oxide (Co‐ZnO) thin film nano‐composites on three different crystalline substrates, viz., Al2O3 (c‐sapphire), silicon (100) (Si), and SiO2 (quartz) is reported, using pulsed electron beam ablation (PEBA). The results indicate that the type of substrate has no effect on Co‐ZnO films stoichiometry, morphology, microstructure, and film thickness. The findings show the presence of hexagonal close‐packed metallic Co whose content increases in the films deposited on Al2O3 and Si substrates relatively to SiO2 substrate. The potential of the films as model nano‐catalysts has been evaluated in the context of the Fischer‐Tropsch (FT) process. Fuel fractions, which have been observed in FT liquid products, are rich in diesel and waxes. Specifically, Co‐ZnO/Al2O3 nano‐catalyst shows a selectivity of ~4%, 31%, and 65% towards gasoline, diesel, and waxes, respectively, while Co‐ZnO/SiO2 nano‐catalyst shows a selectivity of ~12%, 51%, and 37%, for gasoline, diesel, and waxes, respectively. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3332–3340, 2018  相似文献   
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