Copper, silver, and gold-reduced graphene oxide nanocomposite (Cu-rGO, Ag-rGO, and Au-rGO) were fabricated via the hydrothermal method, which shows unique physiochemical properties. Environment friendly electromagnetic radiation was employed to synthesize rGO from GO. The nonlinear optical phenomenon of noble metal decorated rGO is predominantly due to excited state absorption, which arises from surface plasmon resonance and increases in defects at the surface due to Cu, Ag, and Au incorporation. It is found that the third-order nonlinear absorption coefficient was in the order of 10− 10 m/W, with notable enhancements in the third-order properties of Au-rGO compared to other nanocomposites and their respective counterparts. Functionalizing rGO induces defect states ( sp3), increasing NLO response. Cu, Ag, and Au exhibit higher Surface-Enhanced Raman Scattering (SERS) activity due to rGO-induced structural modifications. SERS signals are influenced by dominant signals from Au nanorods. The electronic structures for pure and doped rGO were investigated through Density Functional Theory (DFT). The computed partial density of states (PDOS) confirms the enhancement of the state in Au-doped rGO is due to the charge transference from Au to C 2p orbital. The optical absorption spectra and PDOS reveal the possibility of free carrier absorption enhancement in Au which validates experimentally observed higher two-photon absorption (β) value of Au-doped rGO. The tuning of nonlinear optical and SERS behaviour with variation in the noble metal upon rGO provides an easy way to attain tuneable properties which are exceedingly required in both optoelectronics and photonics applications.

Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae), is a serious pest of stored products. We assessed the efficacy of combined application of Beauveria bassiana AAD16 and azadirachtin against P. interpunctella under laboratory conditions by using filter paper dipping method. P. interpunctella larvae showed lowest LT50 in combined application of AAD16 and azadirachtin compared to the application of only azadirachtin. The mycosis rate of P. interpunctella larvae was 100% after 14 days of the combined application while AAD16 only application showed 93%. These findings suggest that B. bassiana AAD16 and azadirachtin combined solution can be an effective controlling technique against P. interpunctella larvae.

Major pests of greenhouse strawberry include Tetranychus kanzawai (Acari: Tetranychidae) and Bemisia tabaci (Hemiptera: Aleyrodidae) causing significant damage in both yield and quality. We compared control efficacy of two entomopathogenic fungus strains of Beauveria bassiana, AAD16 and GHA, against T. kanzawai and B. tabaci. Both fungus were applied as a foliar spray targeting the undersides of leaves. In preliminary studies in the laboratory, adult T. kanzawai and B. tabaci showed lower LT50 values when treated with AAD16 strain compared to GHA. In the greenhouse, the densities of the both mites (adult and nymph) and whiteflies (adult) were significantly reduced with the application of the two fungus strains compared to the control. The mycosis rate was 88-94% in T. kanzawai and 48-59% in B. tabaci on collected leaves. These findings suggest that Beauveria bassiana AAD16 can be an effective mycoinsecticide against both T. kanzawai and B. tabaci.

Activated carbon (AC) is a versatile and extensively employed adsorbent in environmental remediation. It possesses distinct properties that can be enhanced to selectively target specific pollutants through modifications, including chemical impregnation or incorporation into composite materials. In this study, porous calcium alginate beads (PCAB) were synthesized by incorporating AC and natural alginate through ion gelation in a Ca(II) ion-containing solution, with the addition of sodium lauryl sulfate as a surfactant. The prepared PCAB was tested for Cu(II) removal. PCAB exhibited a spherical shape with higher porosity and surface area (160.19 m2. g−1) compared to calcium alginate beads (CAB) (0.04 m2. g−1). The adsorption kinetics followed the pseudo-first-order model for PCAB and the pseudo-second-order model for CAB. The Langmuir isotherm model provided the best fit for adsorption on PCAB, while the Freundlich model was suitable for CAB. Notably, PCAB demonstrated a maximum adsorption capacity of 75.54 mg.g−1, significantly higher than CAB's capacity of 9.16 mg. g−1. Desorption studies demonstrated that 0.1 M CaCl2 exhibited the highest efficiency (90%) in desorbing Cu(II) ions from PCAB, followed by 0.1 M HCl and 0.1 M NaCl. PCAB showed efficient reusability for up to four consecutive adsorption– desorption cycles. The fixed-bed column experiment confirmed the match with the Thomas model to the breakthrough curves with qTH of 120.12 mg.g−1 and 68.03 mg.g−1 at a flow rate of 1 mL.min−1 and 2 mL.min−1, respectively. This study indicated that PCAB could be an effective adsorbent for Cu(II) removal, offering insights for further application and design considerations.