11 research outputs found
Photophysics of substituted [1,4]Benzodioxino[3,2-b]Oxanthrene (BDO) Chromophores and their macromolecules: a spectroscopy and density functional theory study.
Chromophores and macromolecules containing [1,4]benzodioxino[3,2-b]oxanthrene (BDO) has attracted attention since the beginning of this century. Previous studies demonstrated their potential in wide range of applications including gas permeability, hydrogen and energy storage, sensing, and catalysis. Better understanding of the geometrical and electronic structure characteristics of BOD-based chromophores is vital to advance their employment in these applications. This work utilizes spectroscopy techniques coupled with density functional theory methods to provide this required understanding. Substituted BDOs exhibit red-shift of \u3e1 eV in their electronic transitions compared to unsubstituted BDOs. This shift is explained by a molecular orbital reorganization induced by the substituents. Sulfonated BDOs exhibit folding in their backbone compared to the planar dicarbonitrile BDO (BDODC). The folding originates from an O···C interaction between the sulfonyl substitute and the backbone of the chromophore. Photoexcitated BDODC relaxes to its first singlet excited state (S1) in ∼3.8 ps. Fast inter-system crossing (ISC) deactivates S1 to the first triplet excited state (T1) in ∼63 ps. S1 also deactivates to the ground state (S0) through a photoluminescence (PL) process in ∼13 ns. Substituted BDOs retain their geometrical and electronic properties within the framework of the macromolecules. However, evidence suggests the presence of charge-transfer states (CTSs); rationalized by the Frenkel-Davydov exciton model. Theoretical methods indicate geometrical reorganization and charge redistribution associated with the lowest CTS. Spectroscopy methods reveal a relaxation to the S1 of the macromolecules in S1 deactivates through an ISC process in1 undergoes a fast charge-transfer to the CTS inps. Folding of sulfonated BDOs rationalizes the higher gas separation efficiency reported for their membranes. Additionally, the geometrical reorganizations of their excited states provide a new tool to fine-tune their membranes’ pore size for gas separation applications. The red-shift coupled with the fast ISC and charge-transfer processes rationalize the reported photocatalytic activity of BDO-based macromolecules. Co-polymer’s size and composition control are recommended to improve their efficiency in photocatalysis applications
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The Virtual Living Museum: Integrating the Multi-Layered Histories and Cultural Practices of Gadara’s Archaeology in Umm Qais, Jordan
This paper discusses a novel technological approach using virtual heritage technology to reflect Umm Qais heritage’s intertwining and interdependent nature that shapes its identity and value today. It developed the first model of a “virtual living museum” that brings both the tangible and intangible heritage of the site and community together into an integrated virtual environment that gives equal importance to local community narratives, traditions and history. We argue that integrating both human and digital records enriches the virtual twin of cultural heritage sites as a living and more humane experience that best represents the multi-layered and overlapping history of ancient Gadara’s archaeology and the cultural practices within Hara Fouqa and its Ottoman houses. As heritage is neither one dimensional nor frozen in time, virtual experiences must be fluid, dynamic, inclusive, integrative and open to change, reflecting living historical narratives
Conservation and tourism Jordan's post eighteenth century architectural heritage
SIGLEAvailable from British Library Document Supply Centre- DSC:DXN054962 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Raw data files for the manuscript \u27Elastin Recoil is Driven by the Hydrophobic Effect\u27
These are the raw data files associated with the manuscript \u27Elastin Recoil is Driven by the Hydrophobic Effect\u27 by Nour M. Jamhawi, Ronald L. Koder, and Richard J. Wittebor
Tourist Movement Patterns and the Effects of Spatial Configuration in a Cultural Heritage and Urban Destination: The Case of Madaba, Jordan
This study investigated the impact of spatial configuration on tourist movement patterns and its role in managing cultural heritage destinations in the city of Madaba. Understanding tourist movement patterns is important for the development of sustainable tourism practices in cultural heritage destinations, as it can help to identify attractions of high tourist impact and inform the development of strategies to mitigate the negative impacts on site preservation and management. Madaba is one of the largest homes to ancient mosaics and is one of Jordan’s most important cultural heritage tourism destinations. This study was carried out using a variety of methods, including observation, site exploration, tourist diaries, questionnaires, and interviews. Space syntax was one of the spatial analytical tools used to assess connectivity and integration. The study found that the arrangement of attraction points and routes, physical and visual connectivity, accessibility, and the location of tourist activities all influenced the spatial behavior of tourists. The findings of this study can be used to guide management and development policies such as redistributing tourist flow, managing and developing tourism resources, and promoting the adaptation of sustainable tourism