An ultrafine grained Al-0.3wt. %Cu has been produced by cold rolling to a thickness reduction of 98% (ε vM =4.5). The deformed structure is a typical lamellar structure with a boundary spacing of 200nm as characterized by transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD). Coarsening of the deformed structure to recrystallization is achieved by heat treatment in the range of 100~300℃.Good thermal stability has been observed up to 175℃ with some segregation of Cu to the boundaries as observed by 3D atom probe characterization. Tensile tests have shown a flow stress (0.2% offset) of 198MPa with continuous flow with no yield drop and Lüders elongation. To quantify the contribution of boundary strengthening to the flow stress, dislocation strengthening and solid solution hardening have been calculated and subtracted from the flow stress. It has been found that boundary strengthening can be expressed by a Hall-Petch relationship and that these constants in this equation are in very good agreement with precious observation of recrystallized pure polycrystalline aluminium with a grain size in the tens of micrometer range. Thereby the Hall-Petch relationship of aluminium can be extended an order of magnitude from the micrometer to the sub-micrometer range, which is of both scientific and technical importance.

Currently, exploration of alternative energy resources is hotly debated among the scientific community owing to rising energy crises and environmental issues. Biodiesel, as renewable energy source proves to be a better option and substitute to petro diesel. In this regard, nonedible seeds could be a better feedstock for synthesizing biodiesel due to their cost effectiveness and environmental friendly attributes. The present study, therefore, deals with the exploration and identification of micromorphologic features among eight novel nonedible oil yielding seeds via scanning electron microscopy (SEM) as potential feedstock for biodiesel industry. Light microscopic studies revealed that seeds size vary from 0.1-2.9 cm in length to 0.1-3 cm in width. Moreover, a great variation in seed color from black, green, and different shades of brown was also observed. Seeds ultrastructure examination by SEM exhibit great variation in seed shape, size, color, sculpturing and periclinal wall shape and arrangement and so on. All the understudy seeds vary from rounded, irregular, subspherical, ellipsoidal, reniform, flattened, polygonal, ovate, pyriform, oblong, and globose shape. Seeds wall structure exhibits great variation from entire, angular, straight, irregular, polygonal, smooth, and elongated. The periclinal wall pattern exhibits variation from flat to slightly concave-convex with straight, angular, undulate, or dentate seeds margin. Among the studied species only Argemone ochroleuca Linn. (Papaveraceae) possess micropylar peak, ridged raphe, and basal helium. The obtained results from the present study would therefore, suggest that SEM could be a useful tool in refreshing the veiled micromorphological features among different oil yielding seeds which in turn helps the researchers for their correct identification, exploration, authentication, and seeds classification in future. K E Y W O R D S energy crises, identification, nonedible oil yielding seeds, scanning electron microscopy, seed micromorphology 1 | INTRODUCTIONEnergy is vital in our lives to streamline transportation, industrial, and power generation sectors. Globally, energy demand has been satisfied by the fossil fuel reservoirs and its urgency seems to increase steadily due to significant competences provided by the unique and renewable technologies followed by the implementation of meticulous energy plans and environmental regulations (Milano et al., 2018). This scenario had raised international awareness of energy crises due to the dramatic shift in fuel prices along with the dwindling of fossil fuel

Nanocrystalline ZnO thin films have been fabricated by a multi-step solgel method using spin coating technique. Zinc acetate dihydrate, 2-methoxyethanol and monoethanolamine were used as a starting material, solvent and stabilizer, respectively. X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were employed to characterize structure and morphologies of the as-deposited samples. The results of XRD and SEM showed that the heat treatment conditions, final rotational (spinning) speed, fume exhaust and precise control of concentration of reactants (precursor and solvent used) strongly affect the crystallographic orientation and morphology of the resultant ZnO films. The XRD pattern showed that the ZnO films formed the preferred orientation along c-axis and the grain size is 16nm for the samples. Only one peak corresponding to the (002) plane at 2θ = 34.34 appears on the diffractograms. The as-deposited films had a transparency of greater than 80% in the visible-near IR region from 400 nm - 800 nm. The optical band gap energy and thickness were calculated to be 3.296 eV and 266 nm respectively

The objective of this research work was to estimate the effect of thermal cycling on the tensile behavior of CARALL composites. Fiber metal laminates (FMLs), based on 2D woven carbon fabric and 2024-T3 Alclad aluminum alloy sheet were manufactured by pressure molding technique followed by hand layup method. Before fabrication, aluminum sheets were anodized with phosphoric acid to produce a micro porous alumina layer on surface. This microporous layer is beneficial to produce a strong bond between the metal and fiber surfaces in FMLs. The effect of thermal cycling (-65 to +70ºC) on the tensile behavior of Cf/Al based FML was studied. Tensile strength was increased after 10 thermal cycles, but it was decreased slightly to some extent after 30 and 50 thermal cycles. Tensile modulus also show similar behavior as that of tensile strength.

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Mg-Al layer double hydroxide (LDH) intercalated with sodium gluconate (SG) is successfully synthesized on the AZ31. The hydrothermal treatment is utilized to develop the LDH coating and three different concentrations of SG, such as 0.1, 0.15, and 0.30[Formula: see text]M were tried to intercalate into the Mg-Al LDH. The crystalline structure of the produced coating reveals that only 0.30[Formula: see text]M of SG can provide sufficient anions to develop the LDH structure. The morphological features are evincing the concentration dependence of produced coatings. Fourier transform infra-red (FTIR) spectroscopy is performed to confirm the intercalation of SG. Moreover, the electrochemical characterization shows that the optimum concentration of SG can provide better corrosion resistance against aggressive electrolyte. Hence, the results of the study reveal that 0.30[Formula: see text]M SG intercalated LDH can provide excellent corrosion resistance to AZ31.