Copper oxide nanoparticles (CuO Nps) were synthesized using Caesalpinia bonducella seed extract via a green synthetic pathway and were evaluated for electrocatalytic properties by carrying out electrochemical detection of riboflavin [vitamin B2 (VB2)]. The seeds of C. bonducella are known to have strong antioxidant properties arising due to the presence of various components, including citrulline, phytosterinin, β-carotene, and flavonoids, which serve as reducing, stabilizing, and capping agents. The synthesized CuO Nps were characterized using UV-visible spectroscopy, Fourier transform infrared spectroscopy, thermogravimetrc analysis-differential thermal analysis, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy and further used as a modifier for a graphite electrode surface. The modified electrode was electrochemically characterized by cyclic voltammetry, square-wave voltammetry, and chronoamperometry techniques and then assessed for electrocatalysis by carrying out the detection of VB2. The electrochemical sensor could be used for nanomolar detection of VB2 with an observed linear range of 3.13-56.3 nM with a limit of detection of 1.04 nM. The electrode showed good stability and reproducibility over a period of 120 days. The CuO Nps were further analyzed for antibacterial effect with Gram-positive and Gram-negative bacteria, and in both cases, high antibacterial activity was clearly observed. The newly synthesized nanoparticles, thus, proved to be an interesting material for electrochemical and biological studies.

Green-Synthesized Rice-Shaped Copper Oxide Nanoparticles Using Caesalpinia bonducella Seed Extract and Their Applications.

Composite materials/structures are advancing in product efficiency, cost-effectiveness and the development of superior specific properties. There are increasing demands in their applications to loa...

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Non-destructive testing and evaluation of composite materials/structures: A state-of-the-art review

/pdf/metallic-nanoparticle-inks-for-3d-printing-of-electronics-vm4ncxes9h.pdf

Metallic Nanoparticle Inks for 3D Printing of Electronics

Advances, limitations and prospects of nondestructive testing and evaluation of thick composites and sandwich structures: A state-of-the-art review

In this work, copper nanowires (NWs) and Cu nanoparticles (NPs) were employed to increase the reliability of a printed electrode pattern under mechanical bending fatigue. The fabricated Cu NW/NP inks with different weight fractions of Cu NWs were printed on a polyimide substrate and flash light-sintered within a few milliseconds at room temperature under ambient conditions. Then, 1000 cycles of outer and inner bending fatigue tests were performed using a lab-made fatigue tester. The flash light-sintered Cu NW/NP ink film with 5 wt % Cu NWs prepared under the flash light-sintering conditions (12.5 J·cm–2 irradiation energy, 10 ms pulse duration, and one pulse) showed a lower resistivity (22.77 μΩ·cm) than those of the only Cu NPs and Cu NWs ink (94.01 μΩ·cm and 104.15 μΩ·cm, respectively). In addition, the resistance change (ΔR·R0–1) of the 5 wt % Cu NWs Cu NW/NP film was greatly enhanced to 4.19 compared to the 92.75 of the Cu NPs film obtained under mechanical fatigue conditions over 1000 cycles and an o...

A highly reliable copper nanowire/nanoparticle ink pattern with high conductivity on flexible substrate prepared via a flash light-sintering technique.

Nondestructive evaluation of hidden multi-delamination in a glass-fiber-reinforced plastic composite using terahertz spectroscopy

Copper nanoparticles (Cu-Nps) are one of the promising material for the advancement of nanoscience and technology. In this work, we successfully synthesized Cu-Nps using sodium hydroxymethanesulinate (Rongalite) as a novel reducing agent via solution process. Cu-Nps were achieved from chemical reduction of copper salt within 10-20 min at low temperature without using any complexing agent. In order to investigate the phase, size, and composition of the synthesized Cu-Nps, X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) were employed. Average particle size of the synthesized Cu-Nps is 152 nm. It is expected that the outcomes of this study take a step closer towards designing general strategies for a simple, environment friendly and low cost synthesis method of Cu-Nps. The synthesized Cu-Nps are mixed with commercial Cu-Nps and sintered using photonic sintering process. To determine the optimum sintering energy, the flash light irradiation energy was varied and optimized. An XRD and SEM were used to characterize the sintered Cu-Nps. The resulting sintered Cu-Nps exhibited a low resistivity (20.73 μΩcm) without any damages of the polymer substrate.

Synthesis and Characterization of Copper Nanoparticles (Cu-Nps) using Rongalite as Reducing Agent and Photonic Sintering of Cu-Nps Ink for Printed Electronics

In this work, the terahertz (THz) spectroscopy system was used for the detecting and evaluation of hidden damages in a glass fiber reinforced plastic (GFRP). The interaction between THz and the GFRP was analyzed including the effects of reflecting, scattering and absorption of THz radiations with respect to the type of hidden damage. Both the transmission and reflective configurations were used to investigate the hidden damages including the delamination, fiber fracture and moisture absorption. Finally, the hidden damages inside of the composite laminates were successfully imaged simultaneously based on the time-domain spectroscopy of THz radiation. Additionally, the moisture absorption damage in the GFRP could be detected by analyzing of the frequency domain spectrum. It is expected that the developed THz nondestructive evaluation (NDE) technique can be widely used to evaluate the health of the composite structures.

Nondestructive evaluation of hidden damages in glass fiber reinforced plastic by using the terahertz spectroscopy

The effect of poly (N-vinylpyrrolidone) molecular weight on flash light sintering of copper nanopaste

Intense pulsed light sintering of Cu nano particles/micro particles-ink assisted with heating and vacuum holding of substrate for warpage free printed electronic circuit

Chung-Hyeon Ryu

Papers

Nondestructive evaluation of hidden multi-delamination in a glass-fiber-reinforced plastic composite using terahertz spectroscopy

Synthesis and Characterization of Copper Nanoparticles (Cu-Nps) using Rongalite as Reducing Agent and Photonic Sintering of Cu-Nps Ink for Printed Electronics

Nondestructive evaluation of hidden damages in glass fiber reinforced plastic by using the terahertz spectroscopy

The effect of poly (N-vinylpyrrolidone) molecular weight on flash light sintering of copper nanopaste

Intense pulsed light sintering of Cu nano particles/micro particles-ink assisted with heating and vacuum holding of substrate for warpage free printed electronic circuit