Search

UiO-66 analogues are good candidates as stationary phase in HPLC because of their chemical/thermal stability, large surface area, and two cage structures. Here, two UiO-66 analogues, UiO-66-NH2 and UiO-67, were synthesized and used as stationary phase in HPLC to evaluate their performance in the separation of substituted benzenes (SBs) and polycyclic aromatic hydrocarbons (PAHs). The results showed that SBs could be well separated on UiO-66-NH2 column but not on UiO-67 column. Nonetheless, PAHs could be well separated on UiO-67 column. The separation mechanisms of SBs and PAHs on UiO-66 analogues may be involved in the pore size and functional group in the frameworks of UiO-66 analogues. Introduction of the–NH2 into UiO-66 significantly reduced its adsorption capacity for SB congeners, which resulted in less separation of SBs on UiO-66-NH2. As for the separation of PAHs on UiO-67 column, the π-π stacking effect was supposed to play a vital role. [ABSTRACT FROM AUTHOR]

Suitability of plant tissues as food for insects varies from plant to plant. In lepidopteran insects, fitness is largely dependent on the host-finding ability of the females. Existing studies have suggested that polyphagous lepidopterans preferentially select certain host plant species for oviposition. However, the mechanisms for host recognition and selection have not been fully elucidated. For the polyphagous yellow peach moth Conogethes punctiferalis, we explored the effect of chestnut cultivar on the performance and fitness and addressed the mechanisms of plant-volatile-mediated host recognition. By carrying out laboratory experiments and field investigation on four chestnut Castanea mollissima cultivars (Huaihuang, Huaijiu, Yanhong, and Shisheng), we found that C. punctiferalis females preferentially select Huaijiu for oviposition and infestation, and caterpillars fed on Huaijiu achieved slightly greater fitness than those fed on the other three chestnut cultivars, indicating that Huaijiu was a better suitable host for C. punctiferalis. Plant volatiles played important roles in host recognition by C. punctiferalis. All seven chestnut volatile compounds, α-pinene, camphene, β-thujene, β-pinene, eucalyptol, 3-carene, and nonanal, could trigger EAG responses in C. punctiferalis. The ubiquitous plant terpenoids, α-pinene, camphene and β-pinene, and their specific combination at concentrations and proportions similar to the emissions from the four chestnut cultivars, was sufficient to elicit host recognition behavior of female C. punctiferalis. Nonanal and a mixture containing nonanal, that mimicked the emission of C. punctiferalis infested chestnut fruits, caused avoidance response. The outcome demonstrates the effects of chestnut cultivars on the performance of C. punctiferalis and reveals the preference-performance relationship between C. punctiferalis adults and their offspring. The observed olfactory plasticity in the plant-volatile-mediated host recognition may be important for the forming of the relationship between yellow peach moth and chestnuts since it allows the polyphagous herbivores to adjust to variation in volatile emission from their host plants. [ABSTRACT FROM AUTHOR]