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In this contribution, we describe the kinetics associated with the rac-Me2Si[2-Me-4-Ph-Ind]2ZrCl2 (Cat-1)/borate/TIBA catalyzed copolymerization of E/dienes (isoprene (IP), butadiene (BD), 5-ethylidene-2-norbornene (ENB), 4-vinylcyclohexene (VCH) and vinyl norbornene (VNB)), and E/diene/1-hexene (1H) terpolymerization by using thiophenecarbonyl chloride (TPCC) that was used in Ziegler-Natta (Z-N) and metallocene-catalyzed polyethylene (PE) and polypropylene (PP) and E/P polymerizations. In both types of polymerizations, a higher amount of dienes was incorporated when VNB (2.70 mole %) and VCH (1.56 mole %) were added as comonomer, but IP and BD were incorporated with the moderated rate (0.6-1.1 mole %) with higher activities (3.45x106gm/mmolMt·h). The active center [Zr]/[C*] fraction is higher (61%) than previously reported PE polymerizations, especially in the case of E/IP, E/BD and E/IP/1H but lower than E/P (87%) copolymerization. Significantly, IP and BD activated the inactive catalytic sites that were dormant in the PE. The propagation rate constant (kpE) with IP was higher (kp564 Lmol-1s-1), while kpE with VNB (kp379 Lmol-1s-1) and VCH (kp304 Lmol-1s-1), which were lower than PE. This difference is built because of the diffusion barrier in the system. Compared to E/diene copolymers, kpE values in E/diene/1H terpolymerizations for IP, VCH, and VNB are higher and stable except ENB and determine that 1H prevents the insertion of dienes and reduces the crystalline properties resultant moderate kpE. Even though the E/BD copolymers decreased butadiene content of over 2 mol% resulted in better crystalline characteristics, lower diffusion barriers, and a higher kpE value. In concept, IP and BD are linear and readily available for coordination. While VCH, ENB and VNB are cyclic and bulky, metallocene in contact ion pairs cannot accept ENB, VNB, and VCH for coordination and subsequently act as dormant in the polymerization. [ABSTRACT FROM AUTHOR]

The major goal of this study was to fabricate ZnO nanoparticles (NPs) via chemical and biological routes to evaluate and compare their physiochemical behavior (size and morphology) and biological potentials. The synthesized NPs were confirmed via various spectroscopy and imagining techniques such as XRD, FT-IR, HPLC and SEM. The characterized NPs were then assessed for various in vitro biological applications. Furthermore, apoptotic potential was investigated using HepG2 cell lines by evaluating various signature markers of apoptosis including mitochondrial membrane potential, reactive oxygen/nitrogen (ROS/RNS) production, peroxidases and pro-apoptotic caspase 3 activation. Crystalline, hexagonal structured NPs with an average crystalline size distribution of 32 nm and 23 nm was obtained. Both green-mediated zinc oxide nanoparticles (G-ZnO NPs) and chemically derived NPs (C-ZnO NPs) exhibited high antioxidant, moderate enzyme inhibition, antibacterial and cytotoxicity potential. However, G-ZnO NPs exhibited excellent DPPH (80.1% ± 1.3%), TPC (97 ± 1.22 µgAAE/mg), TRP (94.5 ± 1.48 µgAAE/mg), lipase inhibition (82%), urease inhibition (81.3%), and α-amylase inhibition (18.9%) activity as compared to C-ZnO NPs. Both G-ZnO NPs and C-ZnO NPs showed good antimicrobial potential, however, effect of G-ZnO NPs was more potent than counter C-ZnO NPs. Results from apoptotic assays revealed that G-ZnO NPs showed excellent apoptotic potential in contrast to C-ZnO NPs. Overall results suggested that green route-mediated ZnO NPs exhibits excellent biological potential and could be used for future biomedical applications especially in antimicrobial and cancer therapeutics. To the best of our knowledge, this is the first ever study on Boerhavia diffusa linn-mediated biosynthesis of ZnO nanoparticles and evaluation of their biological activities. [ABSTRACT FROM AUTHOR]

In this work, we focus on the synthesis of Cu0.95Zn0.05O and Cu0.9Zn0.05M0.05O (M = Cr, Co, Cd) nanocrystals by employing low-cost sol–gel method. The effect of single doping and co-doping on physical, antibacterial, and photocatalytic properties of CuO has been successfully investigated using characterization tools comprising XRD, SEM, FTIR, UV–Vis, and I–V measurements. X-ray diffraction pattern exhibited that the grown product of CuO has no traces of impurities, indicated the successful incorporation of dopants without changing monoclinic structure. The X-ray peak profile analysis was adopted to calculate the average crystallite size (D) by considering the contributions of lattice strain on peak broadening. The calculated direct energy bandgap indicated redshift (1.26 eV to 1.81) eV by co-doping. The I–V study revealed the enhancement in electrical properties by co-doping. The effects of co-doping on photocatalytic properties of CuO were studied by degradation of methylene blue (MB) and methyl orange (MO) dyes under direct sunlight. The Zn/Cd-doped nanocrystal has a higher degradation efficiency 98.4% against MB and 96.1% against MO dye in 50 min. The enhanced photodegradation is due to the generation of reactive species confirmed by scavenger's experiments. The recyclability test showed the reusability of grown catalyst up to the 4th cycle. The antibacterial property was studied against Staphylococcus aureus and Klebsiella pneumoniae bacterial strains, which showed the highest zone of inhibition 31 mm, and 32 mm for co-doped samples. Furthermore, the present study paves the path to modify the properties of CuO for optoelectronic devices, environmental, and biomedical applications. [ABSTRACT FROM AUTHOR]