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1.
Protection of Metals and Physical Chemistry of Surfaces - The anti-corrosive Zn and Zn–Ni alloy coatings were electrodeposited on different copper substrates using an optimized sulphate...  相似文献   
2.
Application of brown titanium dioxide (TiO2-x) and its modified composite forms in the photocatalytic decomposition of organic pollutants in the environment is a promising way to provide solutions for environmental redemption. Herein, we report the synthesis of effective and stable TiO2-x nanoparticles with g-C3N4, RGO, and multiwalled carbon nanotubes (CNTs) using a simple hydrothermal method. Among all the as-synthesized samples, excellent photocatalytic degradation activity was observed for RGO-TiO2-x nanocomposite with high rate constants of 0.075 min?1, 0.083 min?1 and 0.093 min?1 for methylene blue, rhodamine-B, and rosebengal dyes under UV–Visible light irradiation, respectively. The altered bandgap (1.8 eV) and the large surface area of RGO-TiO2-x nanocomposite impacts on both absorption of visible light and efficiency of photogenerated charge electron (e?)/hole (h+) pair separation. This resulted in enhanced photocatalytic property of carbon-based TiO2-x nanocomposites. A systematic study on the influence of different carbon nanostructures on the photocatalytic activity of brown TiO2-x is carried out.  相似文献   
3.
Journal of Applied Electrochemistry - The inhibitive action of 2-aminobenzothiazole (ABT) on the corrosion of AA6061-T6 was evaluated in 0.5 M HCl by electrochemical techniques. The...  相似文献   
4.
Membrane separation methods such as electrodialysis (ED) can reduce the volume load on evaporators by facilitating further concentration of rejects from reverse osmosis (RO) plants. ED studies were carried out on a bench-scale system using five membrane cell pairs to obtain a textile effluent concentrate containing approximately 6 times the quantity of salts present in the RO reject. The limiting current densities were determined to be in the range 2.15–3.35 amp/m2 for feed flow rates varying from 18 to 108 L/h. Apart from feed rate, the influence of volume of concentrate and current on membrane performance was evaluated to optimize current utilization. An estimation of energy requirement of an integrated process constituting ED and evaporation for concentration of inorganics present in textile effluent from 4.35% to 24% was made and found to be approximately one eighth of the operating cost incurred by evaporation alone. Detailed design of a commercial ED system revealed that a membrane area of 13.1 m2 was required to treat a feed rate of 1500 L/h. The payback period to recover capital investment was found to be 110 days.  相似文献   
5.
The paper describes the methodology of modeling and simulation of bird impact mechanism of GLARE laminate structures. The bird is modeled using Lagrangian concept. Explicit finite element techniques have been developed to simulate the impact mechanics. The study involves deeper understanding of impact dynamics and contact mechanics. The bird impact analysis has been carried out on typical configuration of GLARE 3/2, 4/3, 5/4, 6/5, 7/6 and 8/7. The results of stress propagation and material deformation at high strain rate have been obtained. Results from the numerical analysis are compared with experimental results, and the material is found to be capable of absorbing the impact energy. The results also show that the bird material model chosen to simulate for carrying out impact mechanics analysis is found to be capable of capturing most of the complex behavior exhibited by functional structural material GLARE.  相似文献   
6.
This paper summarizes the inhibitor activity of various reported thiourea derivatives in acid media used against the deterioration of mild steel. Acid solutions have been extensively employed in manufacturing and many industrial processes for pickling and removal of undesirable scale. Mild steel is highly susceptible to corrosion in such aggressive acid media. The additives such as inhibitors are widely employed in those cases to reduce the extent of corrosion as much as possible. The survey of literature on organic inhibitors clearly indicates the potential usage of thiourea derivatives as inhibitors of mild steel corrosion. The influence of physical-chemical properties on the inhibition activity of thiourea derivatives has been discussed. This information is highly useful for different industrial applications where good performing inhibitors are being required for protecting mild steel from aggressive acid media.  相似文献   
7.
International Journal on Software Tools for Technology Transfer - Debugging cyber-physical system (CPS) models is a cumbersome and costly activity. CPS models combine continuous and discrete...  相似文献   
8.
The work significantly optimizes growth parameters for nanostructured and flat GaN film in the 480–830 °C temperature range. The growth of ordered, high quality GaN nanowall hexagonal honeycomb like network on c-plane sapphire under nitrogen rich (N/Ga ratio of 100) conditions at temperatures below 700 °C is demonstrated. The walls are c-oriented wurtzite structures 200 nm wide at base and taper to 10 nm at apex, manifesting electron confinement effects to tune optoelectronic properties. For substrate temperatures above 700 °C the nanowalls thicken to a flat morphology with a dislocation density of 1010/cm2. The role of misfit dislocations in the GaN overlayer evolution is discussed in terms of growth kinetics being influenced by adatom diffusion, interactions and bonding at different temperatures. The GaN films are characterized by reflection high energy electron diffraction (RHEED), field emission scanning electron (FESEM), high resolution X-ray diffraction (HRXRD) and cathodoluminescence (CL).  相似文献   
9.
Tapioca starch has been crosslinked and blended with 10% low density polyethylene (LDPE) with varying quantities of silane treated nanoclay using an epoxy functionalized LDPE as compatibilizer. The mechanical, thermal, water absorption, and biodegradability characteristics were investigated. The mechanical properties were considerably improved by crosslinking as compared to uncrosslinked composites. The flexural properties increased by more than 50% while tensile strength increased by one and half times. Biodegradability was initially inhibited but became rapid after the initial lag period. POLYM. COMPOS., 37:1384–1395, 2016. © 2014 Society of Plastics Engineers  相似文献   
10.
Light transmission in polycrystalline magnesium fluoride was studied as a function of the mean grain size at different wavelengths. The mean grain size was varied by annealing hot‐pressed billets in argon atmosphere at temperatures ranging from 600°C to 800°C for 1 h. The grain‐size and grain‐orientation distributions were characterized by electron back scatter diffraction. The scattering coefficients were calculated from the in‐line transmittance measured at various wavelengths. The scattering coefficient of polycrystalline magnesium fluoride increased linearly with the mean grain size and inversely with the square of the wavelength of light. It is shown that these trends are consistent with theoretical models based on both a limiting form of the Raleigh–Gans–Debye (RGD) theory of particle scattering and light retardation theories that take refractive index variations along the light path. Quantitative predictions of the theories are, however, subject to uncertainly due to the restrictive assumptions made in the theories and difficulties in representing the microstructure in the theoretical models. In particular, grain‐size distribution has a significant influence on the scattering coefficient calculated using particle scattering models.  相似文献   
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