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871.
Tatiana Loureiro Rocio Macarena Moyano Dip Elizabete Lucas Luciana Spinelli 《Journal of Polymers and the Environment》2018,26(2):555-566
Cashew nut shell liquid (CNSL) is a byproduct of the cashew nut industry and consists predominantly of phenolic compounds that have an side chain with different degrees of unsaturation. Cardanol, one of these components, is biodegradable and widely available. Studies have revealed several polymerization reactions involving cardanol. However, the mechanisms and detailed structures of polymerization reactions have not been explored, although the final product shows different applications. In this work, we evaluated the mechanism and the products structure of the reaction of cardanol with: (i) boron trifluoride diethyl etherate (BF3O(CH2CH3)2), and (ii) formaldehyde. The characterizations were performed by FTIR, 1H NMR, SEC and TGA. The results show that the reaction of cardanol with aldehyde produces the expected like-comb structure with a long hydrocarbon pendent chain. Nevertheless, the reaction of cardanol with BF3O(CH2CH3)2 can exhibits a more complex structure since it was identified aromatic ring linkages, besides the expected polymerization through C=C. 相似文献
872.
María Martínez-Jauregui Miguel Delibes-Mateos Beatriz Arroyo Mario Soliño 《Conservation biology》2020,34(4):868-878
The extraordinary population growth of certain ungulate species is increasingly a concern in agroforestry areas because overabundance may negatively affect natural environments and human livelihoods. However, society may have negative perceptions of killing wildlife to reduce their numbers and mitigate damage. We used an online survey that included a choice experiment to determine Spanish citizens’ (n = 190) preferences toward wildlife population control measures related to negative effects of ungulate overabundance (negative impacts on vegetation and other wildlife species and disease transmission to livestock) in 2 agroforestry national parks in Spain. We used latent-class and willingness-to-pay in space models to analyze survey results. Two percent of respondents thought a national park should have no human intervention even if lack of management may cause environmental degradation, whereas 95% of respondents favored efforts to reduce damage caused by overabundant ungulate species. We estimated human well-being losses of survey respondents when sustainable effects of deer overabundance on the environment became unsustainable effects and well-being gains when sustainable effects transitioned to no visible effects. We found that the type of wildlife-control program was a very relevant issue for the respondents; indirect control in which killing was avoided was the preferred action. Sixty-six percent of respondents agreed with the option of hunters paying for culling animals to reduce ungulate impacts rather than management cost coming out of taxes, whereas 19% of respondents were against this option and willing to pay for other solutions in national parks. Our results suggest that killing wildlife in national parks could be a socially acceptable tool to manage overabundance problems in certain contexts, but it could also generate social conflicts. 相似文献
873.
Arias-Pérez Rubén D. Taborda Natalia A. Gómez Diana M. Narvaez Jhon Fredy Porras Jazmín Hernandez Juan C. 《Environmental science and pollution research international》2020,27(34):42390-42404
Environmental Science and Pollution Research - Air pollution is an important cause of non-communicable diseases globally with particulate matter (PM) as one of the main air pollutants. PM is... 相似文献
874.
Ortíz-Rodriguez Oscar Orlando Sonnemann Guido Villamizar-G Raquel A. 《Environment, Development and Sustainability》2022,24(3):3982-3999
Environment, Development and Sustainability - At a global level, it has been scientifically reported that the processes of water purification, management and disposal of wastewater, and solid waste... 相似文献
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Ana Cristina Mugetti Alberto Tomás Calcagno Carlos Alberto Brieva María Silvia Glangiobbe Andrea Pagani Silvia G.Gonzalez 《Ambio-人类环境杂志》2004,33(1):67-75
本文描述了南美大陆南部陆地和东南沿海地区环境特性及水生栖息地和群落的现状(GIWA巴塔哥尼亚大陆架亚区),结果来自一项GIWA项目框架任务所完成的一份全面评估,绝大部分依据的是公开发表的数据.分析主要集中在跨边界水资源目前的情况和人类活动带来的影响.内陆水体的栖息地和群落变化主要是由为发电和其他用途而建的水坝和水库引起的.从活水环境到净水环境影响了生境,造成了生物群落的改变.在拉普拉塔(La Plata)河流域,外来入侵物种使本地物种消失.过度捕捞和污染影响了生物多样性,造成了海洋栖息地质量下降.本篇文章讨论了相关的原因,讨论了布宜诺斯艾利斯省和渔业资源由两国共享的阿根廷-乌拉圭公共渔业区对沿海生态环境的政策选择. 相似文献