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Charge delocalization characteristics of regioregular high mobility polymers.
Controlling the regioregularity among the structural units of narrow bandgap conjugated polymer backbones has led to improvements in optoelectronic properties, for example in the mobilities observed in field effect transistor devices. To investigate how the regioregularity affects quantities relevant to hole transport, regioregular and regiorandom oligomers representative of polymeric structures were studied using density functional theory. Several structural and electronic characteristics of the oligomers were compared, including chain planarity, cation spin density, excess charges on molecular units and internal reorganizational energy. The main difference between the regioregular and regiorandom oligomers is found to be the conjugated backbone planarity, while the reorganizational energies calculated are quite similar across the molecular family. This work constitutes the first step on understanding the complex interplay of atomistic changes and an oligomer backbone structure toward modeling the charge transport properties
Computer simulation of a Linde double column
The purpose of this thesis is to develop a Fortran Computer Program to simulate the operation of a Linde Double Column for the separation of air into oxygen and nitrogen. The model outputs the number of contact stages required, the reflux ratio, the heat loads (condenser and reboiler, and the five profiles of temperature, pressure, vapor flow rate, liquid flow rate, and light component composition. From this data, the proposed design can be evaluated, and the effect of varying operating conditions explored
Historical Ecology, Archaeology and Biocultural Landscapes: Cross-Disciplinary Approaches to the Long Anthropocene
From the local to the global scale, human impact is the real protagonist of the Anthro- pocene. It is impossible to understand ecosystems and the landscape without considering the long-term processes of anthropic activities. The driving forces in landscape change are strongly related to historical dynamics. Changes in political regimes, social structures, eco- nomic modes of production, cultural and religious influences—which all traditionally fall within the domain of the humanities—are phenomena entangled with many ecological and environmental factors. Thus, understanding landscapes in the Anthropocene is impossible without a cross-disciplinary approach
Effects of solvent additive on "s-shaped" curves in solution-processed small molecule solar cells.
A novel molecular chromophore, p-SIDT(FBTThCA8)2, is introduced as an electron-donor material for bulk heterojunction (BHJ) solar cells with broad absorption and near ideal energy levels for the use in combination with common acceptor materials. It is found that films cast from chlorobenzene yield devices with strongly s-shaped current-voltage curves, drastically limiting performance. We find that addition of the common solvent additive diiodooctane, in addition to facilitating crystallization, leads to improved vertical phase separation. This yields much better performing devices, with improved curve shape, demonstrating the importance of morphology control in BHJ devices and improving the understanding of the role of solvent additives
BioCultural Landscapes per la rigenerazione innovativa dei territori di montagna
Simplification of agricultural systems, farmland abandonment, uncontrolled urbanization, together with global scale
drivers, determine fast and unpredictable phenomena of hydrogeological instability, biodiversity decline and identity
loss.
Men should hence promote socio-economic resilience and place identity, using biocultural landscapes as a resource.
These landscapes are the outcome of the historical relationship between man and nature, resulting from complex
interactions between biodiversity (at all levels, including species richness, ecosystem and biotope diversity) and
cultural diversity, including material and immaterial aspects (architectural heritage, traditions, customs, local
traditional agricultural practices, dialectal culture).
Traditional water use is one of the main defining factors of traditional agricultural landscapes, characterized by
significantly multiplied and enhanced functions and by the highest degree of biocultural diversity. The integrity of
traditional agricultural landscapes is an indicator of environmental sustainability, socio-economic growth and habitat
resilience. Land management and planning should promote the multi-functionality of biocultural landscapes through
new interdisciplinary frameworks and innovative strategies, aimed at landscape conservation, enhancement and
creative management
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