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Abstract Insecticidal potential of extracts of Citrus aurantifolia, family Rutaceae, was evaluated to control whiteflies, Bemisia tabaci. Biocidal activity directed chromatographic separation of chloroform and butanol fractions, with spectral identification (1D-NMR, 2D-NMR, ESIMS) of the active fractions have been resulted in separation and structural elucidation of for previously described coumarins (bergapten 1, limettin 2, isopimpinellin 3, oxypeucedanin hydrate 4) in addition to a new dimeric coumarin (12R, 12’R)-aurantifolin 5, two known limonoids; 21,23-dihydro-23-methoxy-21-oxolimonin 6, 21,23-dihydro-23-methoxy-21-oxonomilin 7, and two known flavonoid glycosides; scoparin 8, and narcissin 9. Amongst these compounds, narcissin 9 was the most effective after 24 h. of treatment while, (12R, 12’R)-aurantifolin 5 was the most potent against B. tabaci, 3rd instar nymphs after 72 h. of treatment and under laboratory conditions, with LC50 values of 33.31and 15.92 ppm, respectively comparing with the positive control azadirachtin.

Recent studies for nanofluids, did not pay enough attention to the effect of the nanoparticle size and nanofluid stability on the heat transfer rate. In this study, the thermal conductivity (TC) coefficient of silica/deionized water (DW) nanofluid with various sizes of nanoparticles and various rates of nanofluid stability was investigated. Validation experiments, including X-Ray diffraction analysis (XRD), FE-Scanning Electron Microscopy (FE-SEM), Dynamic Light Scattering (DLS), and Zeta Potential (Zp), were carried out to examine the particle sizes and the nanofluid stability. The results illustrated that increasing the temperature leads to the augmentation of the TC coefficient of the SiO2/deionized water in all nanoparticle sizes and all volume concentrations. Also, increasing the volume concentration of the nanofluid leads to the augmentation of the TC coefficient of the nanofluid in all nanoparticle sizes and all temperatures. Eventually, increasing the nanoparticle sizes causes the TC coefficient of the nanofluid to be decreased in all volume concentrations. For the 11 nm nanoparticle size, the amount of the Relative TC (RTC) coefficient enhancement by increasing the temperature was 1.2%, 2.5%, 4.7%, and 6.8% for concentrations of 0.0.1%, 0.1%, 0.5%, and 1%, respectively. For the 50 nm nanoparticle size, this enhancement was from 0.7% to 6.5%, and for the 70 nm nanoparticle size, it was from 0.5% to 5.7%. Finally, Artificial Intelligence (AI) optimization was done to find the optimized size and stability.