The socioeconomic and environmental considerations of energy production have become crucial due to the increasing complexity of the relationship between energy and the environment. In this context, this study aims to develop possible mechanisms for perspectives of energy policy on environmental by exploring the mediating role of renewable energy patents.The study used a non-radial data envelopment analysis (DEA) model and panel data model for 30 Chinese provinces by taking the panel data from 2010 to 2017. The results show that the overall environmental performance index (EPI) of Chinese areas is improved by 9.88% from 2010 to 2017. Further, The econometric model findings offer evidence that provincial renewable energy policies and emission reduction policies positively impact the enhancement of EPI. The results also show that the P values of the single-threshold model and the doublethreshold model both passed the 1% significance test, so it can be concluded that there is a double-threshold effect. Finally, the research findings posed several policy implications based on the research findings.

Bio-degradable and eco-friendly essential oils (EOs) extracted from Mentha longifolia, Salsola imbricata, Erigeron bonariensis, E. canadensis, Ailanthus altissima, and Zanthoxylum armatum were investigated for their repellent and larvicidal potential against Aedes aegypti mosquitoes. The EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis, A. altissima, and Z. armatum exhibited 99.0%, 96.8%, 40.2%, 41.7%, 29.1%, and 13.2% repellency against mosquitoes at a tested dose of 33.3 μg/cm2, respectively. In time span bioassays, the EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis showed more than 40% repellency for 60 min at a tested dose of 330 μg/cm2. Larvicidal bioassays revealed that larvae of Ae. aegypti were the most susceptible to M. longifolia (LC50, 39.3 mg/L), E. bonariensis (LC50, 26.0 mg/L), E. canadensis (LC50, 35.7 mg/L), and Z. armatum (LC50, 35.9 mg/L) EOs upon 48 h exposure. The most abundant constituents in the EOs of M. longifolia, S. imbricata, E. bonariensis, E. canadensis and A. altissima were piperitone oxide (45.5%), carvone (39.9%), matricaria ester (43.1%), (31.7%) and eugenol (24.4%), respectively. Our study demonstrates that EOs of M. longifolia, S. imbricata, E. bonariensis, and E. canadensis might be used to control Ae. aegypti mosquitoes without harming humans or the environment.

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Repellents are effective personal protective means against outdoor biting mosquitoes. Repellent formulations composed of EOs are finding increased popularity among consumers. In this study, after an initial screening of 11 essential oils (EOs) at the concentration of 33 μg/cm2, five of the most repellent EOs, Perovskia atriplicifolia, Citrus reticulata (fruit peels), C. reticulata (leaves), Mentha longifolia, and Dysphania ambrosioides were further investigated for repellent activity against Aedes aegypti mosquitoes in time span bioassays. When tested at the concentrations of 33 μg/cm2, 165 μg/cm2 and 330 μg/cm2, the EO of P. atriplicifolia showed the longest repellent effect up to 75, 90 and 135 min, respectively, which was followed by C. reticulata (peels) for 60, 90 and 120 min, M. longifolia for 45, 60 and 90 min, and C. reticulata (leaves) for 30, 45 and 75 min. Notably, the EO of P. atriplicifolia tested at the dose of 330 μg/cm2 showed complete protection for 60 min which was similar to the commercial mosquito repellent DEET. Gas chromatographic-mass spectrometric analyses of the EOs revealed camphor (19.7%), limonene (92.7%), sabinene (24.9%), carvone (82.6%), and trans-ascaridole (38.8%) as the major constituents of P. atriplicifolia, C. reticulata (peels), C. reticulata (leaves), M. longifolia, and D. ambrosioides, respectively. The results of the present study could help develop plant-based commercial repellents to protect humans from dengue mosquitoes.