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131.
Biodegradation of oxygenated and non-oxygenated imidazolium-based ionic liquids in soil 总被引:1,自引:0,他引:1
Aerobic biodegradation of ionic liquids in soil was monitored for the first time. The tests, followed over six months according to ASTM D 5988-96, were carried out on the four ionic liquids obtained from 1-R-3-methylimidazolium cations, with R=CH(3)(CH(2))(3) and CH(3)O(CH(2))(2), and the tetrafluoroborate and dicyanamide counter anions. The n-butyl derivatives, after an induction period of about two months, were found to be degradable, although the degradation rate with the dicyanamide anion was smaller. In contrast, no significant production of CO(2) was observed in the tests with the methoxyethyl derivatives. Calculations at the B3LYP/6-31G(d) level were carried out to characterize the atomic charge distributions and frontier orbital structures of 1-alkyl-3-methylimidazolium cations and point out the changes caused by replacement of a CH(2) group of the alkyl chain with an oxygen atom. The calculations predict an overall negative charge on the nitrogen atoms of the imidazolium-based cations. The energies of the highest occupied (pi) MO and lowest empty (pi( *)) MO are only slightly perturbed by the length and nature of the alkyl chain. However, the electron-donor properties of the oxy derivatives are radically increased. The HOMO becomes a lone pair orbital mainly localized on the oxygen atom, and its ionization energy is sizeably smaller than that of the outermost ring pi MO. 相似文献
132.
Isabella Fabietti Giulia Grassini Sara Savelli Roberta Vicario Anita Romiti Milena Viggiano Chiara Vassallo Laura Valfrè Paola Giliberti Irma Capolupo Marco Bonito Pietro Bagolan Francesco Morini Leonardo Caforio 《黑龙江环境通报》2023,43(8):1002-1007
Objective
To evaluate fetal brain development using MRI (magnetic resonance imaging) in CDH (congenital diaphragmatic hernia).Methods
52 isolated left CDH and 104 control fetuses were imaged using MRI. Brain morphometry (Biparietal diameter—BPD, brain fronto-occipital diameter—BFOD, third ventricle, posterior ventricles, transcerebellar diameter—TCD, anteroposterior and craniocaudal cerebellar vermis diameter—AP and CC) and cortical structures (bilateral cingulate fissure—CF, insular fissure—IF, insular depth - ID) were compared with controls using Mann–Whitney test.Results
Median gestational age at MRI (p = 0.95)and the median biparietal diameter (p = 0.737) were comparable. Among morphometric parameters, only the brain fronto-occipital diameter was significantly smaller in CDH (p = 0.001) and the third ventricle was significantly greater in CDH (<0.0001). Among cortical structures, the cingulate and insular fissures were significantly deeper in CDH fetuses (p < 0.0001) as the insular depth ID was smaller in CDH (p < 0.03).Conclusions
CDH fetuses have a smaller fronto-occipital diameter, reduced insular depth, deeper cingulate and insular fissure, and greater third ventricle width as compared to controls. These findings suggest that left CDH may have an impact on fetal brain development with an overall reduction in brain volume. 相似文献133.
Environment, Development and Sustainability - The valorization of typical food products contributes to local economy sustainability. The European Union introduced the optional "mountain... 相似文献