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排序方式: 共有475条查询结果,搜索用时 15 毫秒
311.
Marwa B. Hannouf Alejandro Padilla-Rivera Getachew Assefa Ian Gates 《Journal of Industrial Ecology》2023,27(3):707-725
Life cycle sustainability assessment (LCSA) can be used as a tool to understand how products and operating systems can meet the United Nations’ Sustainable Development Goals (SDGs). However, existing linkages between SDGs and LCSA are limited and an analysis of coverage in literature is needed. In this paper, we propose a generic methodological framework establishing connections between LCSA categories at micro-level and SDGs at macro-level based on derivation from the literature. The qualitative heuristic research method developed builds on keyword literature search, bibliometric analysis, mapping, and narrative literature review for connection rationales. By using qualitative assessment levels, an assessment of linkages between LCSA categories and SDGs reveal that “technology development,” “public commitment to sustainability issues,” “access to material resources,” and “education provided in the local community” have the highest number of reported relationships with SDGs. Twenty-two LCSA categories were found with no direct/indirect connection with any SDG; reasons include absence of life cycle thinking perspective in SDGs and lack of sustainability-based discussion for workers, consumers, and value chain actors' stakeholder groups. Despite these gaps, the results provide new insights for industries looking to measure the contribution of their product systems along their life cycle in the context of SDGs supporting them to some extent, to select LCSA categories with either highest number of identified relationships to SDGs or that contribute to prioritized list of SDGs. The approach provides a starting point to improve transparency and consistency of reporting of sustainability performance of product systems by connecting LCSA to the global agenda for sustainable development. 相似文献
312.
二级结构形成:蛋白质折叠起始过程的框架模型 总被引:8,自引:1,他引:7
框架模型认为二级结构形成是蛋白质起始过程的结构基础.文章介绍蛋白质同源片段的溶液构象及其构象研究法和多肽二级结构的从头设计,并综述这些研究成果应用于折叠起始过程的理论模型和蛋白质折叠起始过程的最新研究进展. 相似文献
313.
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315.
Linus Stegbauer Sebastian Zech Gökcen Savasci Tanmay Banerjee Filip Podjaski Katharina Schwinghammer Christian Ochsenfeld Bettina V. Lotsch 《Liver Transplantation》2018,8(24)
Covalent organic frameworks (COFs) have emerged as a new class of crystalline porous polymers displaying molecular tunability combined with structural definition. Here, a series of three conjugated, photoactive azine‐linked COFs based on pyrene building blocks which differ in the number of nitrogen atoms in the peripheral aromatic units is presented. The structure of the COFs is analyzed by combined experimental and computational physisorption as well as quantum‐chemical calculations, which suggest a slipped‐stacked arrangement of the 2D layers. Photocurrents of up to 6 µA cm?2 with subsecond photoresponse times are measured on thin film samples for the first time. While all COFs are capable of producing hydrogen from water, their efficiency increases significantly with decreasing number of nitrogen atoms. The trending activities are rationalized by photoelectrochemical measurements and quantum‐chemical calculations which suggest an increase in the thermodynamic driving force with decreasing nitrogen content to be the origin of the observed differences in hydrogen evolution activities. 相似文献
316.
Xiaxia Li Shasha Zheng Ling Jin Yan Li Pengbiao Geng Huaiguo Xue Huan Pang Qiang Xu 《Liver Transplantation》2018,8(23)
The applications of carbon and carbon‐based materials with high porosity, high surface area, and functionalities based on metal‐organic framework precursors and/or templates have attracted significant research interest in recent years, particularly in the field of batteries. The chemical and physical properties of carbon and carbon‐based materials obtained by the heat treatment of various metal‐organic framework precursors or templates are improved to a certain extent. In this comprehensive review, the synthetic methods and electrochemical performance of carbon materials derived from metal‐organic frameworks (metal/carbon, metal oxide/carbon, nitrogen‐doped carbon, porous carbon, etc.) along with their applications in batteries are outlined. 相似文献
317.
Photocatalysis: Tailor‐Made Photoconductive Pyrene‐Based Covalent Organic Frameworks for Visible‐Light Driven Hydrogen Generation (Adv. Energy Mater. 24/2018)
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318.
欧盟在风险预防方面一直走在世界的前列,其对于转基因生物的法律监管一直奉行的是预防原则。在该原则的指导下,欧盟建立起了极为严苛的转基因生物监管法律框架,并将该原则适用于转基因生物监管的各个环节。囿于预防原则的抽象性、模糊性等缺陷,该原则在欧盟转基因生物监管中的适用引发了成员国滥用保护性措施、国际贸易摩擦加剧等问题以致陷入困境。通过欧盟法院的判例与解释、相关法案的修正等措施,欧盟试图摆脱困境,使得预防原则在转基因生物的监管中起到更加有效的作用。我国对于预防原则存在与欧盟类似的理解与运用,现有法律框架对于转基因生物的监管亦过于严苛。借鉴国外经验,立足本土需要,当前应在充分认识预防原则的基础上,重新审视科学与法律的关系,适度放松转基因生物的法律监管。 相似文献
319.
Enhanced Cathodic Oxygen Reduction and Power Production of Microbial Fuel Cell Based on Noble‐Metal‐Free Electrocatalyst Derived from Metal‐Organic Frameworks
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Shijie You Xiaobo Gong Wei Wang Dianpeng Qi Xiuheng Wang Xiaodong Chen Nanqi Ren 《Liver Transplantation》2016,6(1)
Microbial fuel cell (MFC) can generate electricity from organic substances based on anodic electrochemically active microorganisms and cathodic oxygen reduction reaction (ORR), thus exhibiting promising potential for harvesting electric energy from organic wastewater. The ORR performance is crucial to both power production efficiency and overall cost of MFC. A new type of metal‐organic‐framework‐derived electrocatalysts containing cobalt and nitrogen‐doped carbon (CoNC) is developed, which is effective to enhance activity, selectivity, and stability toward four‐electron ORR in pH‐neutral electrolyte. When glucose is used as the substrate, the maximum power density of 1665 mW m?2 is achieved for the optimized CoNC pyrolyzed at 900 °C, which is 39.8% higher than that of 1191 mW m?2 for commercial Pt/C catalyst in the single‐chamber MFC. The improved performance of CoNC catalyst can be attributed to large surface area, microporous nature, and the involvement of nitrogen‐coordinated cobalt species. These properties enable the efficient ORR by increasing the active sites and enhancing mass transfer of oxygen and protons at “water‐flooding” three‐phase boundary where ORR occurs. This work provides a proof‐of‐concept demonstration of a noble‐metal‐free high‐efficiency and cost‐effective ORR electrocatalyst for effective recovery of electricity from biomass materials and organic wastewater in MFC. 相似文献
320.
Transitional Environments (TEs) have been deeply modified to meet human requirements, and for this reason are currently ranked among the most endangered aquatic ecosystems. The Adriatic basin hosts a large number of TEs of which the Lagoon of Venice is the largest one, but information on its meiofauna are very dated or focused to localized areas. The present study is the first to document the spatial distribution of meiofauna in the whole Venice lagoon. Furthermore, the health status of the TE of Venice has been assessed by means of several faunal parameters (richness, diversity indices, structure of the entire meiofaunal assemblage and only rare taxa). All the univariate meiofaunal parameters (i.e. richness, diversity indices, Ne:Co ratio) were consistent in highlighting the worst ecological quality of the Porto Marghera district. Instead, the structure of the entire meiofaunal assemblage as well as that of rare taxa seemed to detect variations not directly related to pollution and likely due to the different hydrodynamic conditions of Lido and Malamocco inlets. On the basis of our results, we have also critically discussed the usefulness of the various faunal parameters in the monitoring assessment of the TEs. 相似文献