In-situ biosynthesized plant exudate gums­silver nanocomposites as corrosion inhibitors for mild steel in hydrochloric acid medium.

Natural gums due to availability, multifunctionality, and nontoxicity are multifaceted in application. In corrosion inhibition applications, their performance, in unmodified form is unsatisfactory because of high hydration rate, solubility issues, algal and microbial contamination, as well as thermal instability. This work attempts to enhance the inhibitive performance of Berlinia grandiflora (BEG) and cashew (CEG) exudate gums through various modification approaches. The potential of biogenic BEG and CEG gums-silver (Ag) nanocomposites (NCPs) for corrosion inhibition of mild steel in 1 M HCl is studied. The nanocomposites were characterized using the FTIR, UV-vis, and TEM techniques. The corrosion studies through the gravimetric and electrochemical (PDP, EIS, LPR, and EFM) analyses reveal moderate inhibition performance by the nanocomposites. Furthermore, the PDP results reveal that both inhibitors are mixed-type with maximum corrosion inhibition efficiencies (IEs) of 61.2 % and 54.2 % for BEG-Ag NCP and CEG-Ag NCP, respectively at an optimum concentration of 1.0 %. Modification of these inhibitors with iodide ion (KI) significantly increased the IE values to 90.1 % and 88.5 % for BEG-Ag NCP and CEG-Ag NCP at the same concentration. Surface observation of the uninhibited and inhibited steel samples using SEM/EDAX, 3D Surface profilometer, and AFM affirm that the modified nanocomposites are highly effective.

Hydrothermal biomass processing for green energy transition: insights derived from principal component analysis of international patents.

As efforts to achieve Net Zero are intensifying, there is a strong need to identify the technological positioning of green process innovations that can support the green energy transition. A veritable contender to support these efforts is the hydrothermal biomass processing technology. This process innovation comprises diverse techniques that can convert biomass substrates into valuable low-carbon fuels. Coordination across all available conversion approaches is encouraged to propel the application of those that consider the environmental and sustainability impacts. We assessed the innovation intensity for different techniques under this green process innovation through applying natural language processing and deployment of principal component analysis on patent data. We positioned our techniques within four distinctive groups (intense, dormant, emerging, and exploratory). In this way, we tracked which hydrothermal technique currently dominates international applications and which ones are gaining traction in the future.

Tunable plasmonic effects arising from metal-dielectric nanorods.

We have investigated the plasmonic effects in a two-dimensional periodic array of metallodielectric nanorods with and without the rotational angle, in which the integration of the localized surface plasmon resonance (SPR) and hollow plasmon resonance (HPR) properties is performed. Four patterns of nanostructures are investigated. We make use of the three-dimensional finite element method to obtain the simulation results, which demonstrate that the localized SPR and HPR in metallodielectric nanorods enhance the near-field intensity and increase the depth of the transmittance dip, providing an additional degree of freedom in the control of the light wave at the nanoscale. Numerical results show that the depth of the transmittance dip and sensitivity of case 1 and case 2 can be elevated to a value of 83.21% and 6.7 times, respectively, when the rotational angle of metal-dielectric nanorods varies from 0° to 90°. The sensitivity of case 3 and case 4 can be raised to the magnitude of 700-1091 nm/RIU (where RIU is the refractive index unit), and the characteristics enable the extensive applications for nanophotonic devices with high performance in a predictable manner.

Tunable Optical Performances on a Periodic Array of Plasmonic Bowtie Nanoantennas with Hollow Cavities.

We propose a design method to tune the near-field intensities and absorption spectra of a periodic array of plasmonic bowtie nanoantennas (PBNAs) by introducing the hollow cavities inside the metal nanostructures. The numerical method is performed by finite element method that demonstrates the engineered hollow PBNAs can tune the optical spectrum in the range of 400-3000 nm. Simulation results show the hollow number is a key factor for enhancing the cavity plasmon resonance with respect to the hotspot region in PBNAs. The design efforts primarily concentrate on shifting the operation wavelength and enhancing the local fields by manipulating the filling dielectric medium, outline film thickness, and hollow number in PBNAs. Such characteristics indicate that the proposed hollow PBNAs can be a potential candidate for plasmonic enhancers and absorbers in multifunctional opto-electronic biosensors.