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The role played by hollow ceramic thin-walled aluminium oxide microballoons on the shear deformation characteristics of AZ31 Magnesium syntactic foam is studied through high-speed machining. The ceramic microballoons embedded in the AZ31 matrix provides the necessary stiffness for these novel foams. The effect of hollow ceramic microballoon properties, such as the volume fraction, thin wall thickness to diameter ratio, and microballoon diameter, profoundly affects the chip formation. A novel force model has been proposed to explain the causes of variation in cutting forces during chip formation. The results showed an increase in machining forces during cutting AZ31 foams dispersed with higher volume fraction and finer microballoons. At a lower (Davg/h) ratio, the mode of microballoon deformation was a combination of bubble burst and fracture through an effective load transfer mechanism with the plastic AZ31 Mg matrix. The developed force model explained the key role played by AZ31 matrix/alumina microballoon on tool surface friction and showed a better agreement with measured machining forces.

For machining of composites, Abrasive Water Jet Machining is widely employed. For assembly of the machine tool structure, production of slots is essential. In this paper, abrasive water jet machining of composite laminates was experimentally investigated for various cutting parameters in terms of average surface roughness (R a ) and kerf taper (K t ).By generating a response surface model, the experimental values obtained for quality characteristics (R a and K t ) were empirically related to cutting parameters. The effects of cutting parameters on quality characteristics were analyzed by utilizing empirical models and also optimized within the tested range based on desirability approach. The optimum parameter levels were also validated by confirmation test. From this investigation, it is evident that, for obtaining a minimum kerf taper, traverse speed, water pressure and abrasive mass flow rate are significant parameters and for obtaining less surface roughness traverse speed is the significant parameter.

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poly((N-(4-((E)-3oxo-3-(10H-phenothiazin-8-yl) prop-1-enyl) phenyl) acrylamide), were synthesized by Claisen-Schmidt condensation reaction, followed by ultrasonic irradiation reduction. The synthesized polymers were characterized by Fourier transform infrared spectroscopy, 1 H nuclear magnetic resonance, and 13 C nuclear magnetic resonance spectroscopic technique. The newly synthesized polymers have been screened for antibacterial and antifungal activities by using resazurin reduction assay method, and the resulting polyacrylamides showed promising activity against various tested bacteria and fungi. Among the polymers, poly((N-(4-((E)-3-oxo-3-(10H-phenothiazin-8-yl) prop-1-enyl) phenyl) acrylamide) and poly((N-(4-((E)-3-(1H-indol-3-yl)-3-oxoprop-1-enyl) phenyl) acrylamide) exhibited better antifungal and antibacterial activities than poly ((N-(4-((E)-3-(naphthalen-6-yl)-3-oxoprop-1-enyl) phenyl) acrylamide), whereas all the polymers do not show any sign of antibacterial and antifungal activity against Streptococcus faecalis and Candida glabrata.

A novel series of anthracene-based chalcone derivatives were synthesized and evaluated in terms of their antibacterial and antifungal activities.

Herein, we report four metal-free organic polymethacrylates (In-In-BzI)PMA, (Ac-In-BzI)PMA, (TPA-In-BzI)PMA, and (Py-In-BzI)PMA with pendant chromophores donor-pconjugated-acceptor (D-p-A) molecular framework as photosensitizers for dye-sensitized solar cells (DSSCs). In which the donor-acceptor units are attached by an indole-chalcone extending side chain to inhibit back electron transfer and charge recombination; the p-linker component contains varied chalcone-based substituents to enhance the sunlightharvesting ability of the solar device. Photon-current cells based on the DSSC format were fabricated using the polymers as sensitizers. The DSSC device assembled using (TPA-In-BzI)PMA exhibits a considerably better IPCE peak and J-V response, with an overall power conversion efficiency of 3.70% under the illumination of AM 1.5G (100 mW cm -2 ).