16 research outputs found
Fabrication of 3D Oriented MOF Micropatterns with Anisotropic Fluorescent Properties
Published online: May 2, 2023Micropatterning crystalline materials with oriented pores is necessary for the fabrication of devices with anisotropic properties. Crystalline and porous metal–organic frameworks (MOFs) are ideal materials as their chemical and structural mutability enables precise tuning of functional properties for applications ranging from microelectronics to photonics. Herein, a patternable oriented MOF film is designed: by using a photomask under X-ray exposure, the MOF film decomposes in the irradiated areas, remaining intact in the unexposed regions. The MOF film acts simultaneously as a resist and as functional porous material. While the heteroepitaxial growth from aligned Cu(OH)₂ nanobelts is used to deposit oriented MOF films, the sensitivity to radiation is achieved by integrating a brominated dicarboxylate ligand (Br₂BDC) into a copper-based MOF Cu₂L₂DABCO (DABCO = 1,4-diazabicyclo[2.2.2]octane; L = BDC/Br₂BDC). The lithographed samples act as diffraction gratings upon irradiation with a laser, thus confirming the quality of the extended MOF micropattern. Furthermore, the oriented MOF patterns are functionalized with fluorescent dyes. As a result, by rotating the polarization angle of the laser excitation, the alignment of the dye in the MOF is demonstrated. By controlling the functional response to light, this MOF patterning protocol can be used for the microfabrication of optical components for photonic devices.Miriam de J. Velásquez-Hernández, Mercedes Linares-Moreau, Lea A. Brandner, Benedetta Marmiroli, Mariano Barella, Guillermo P. Acuna, Simone Dal Zilio, Margot F. K. Verstreken, Dmitry E. Kravchenko, Oliver M. Linder-Patton, Jack D. Evans, Helmar Wiltsche, Francesco Carraro, Heimo Wolinski, Rob Ameloot, Christian Doonan, and Paolo Falcar
PRISM-games: verification and strategy synthesis for stochastic multi-player games with multiple objectives
PRISM-games is a tool for modelling, verification and strategy synthesis for stochastic multi-player games. These allow models to incorporate both probability, to represent uncertainty, unreliability or randomisation, and game-theoretic aspects, for systems where different entities have opposing objectives. Applications include autonomous transport, security protocols, energy management systems and many more. We provide a detailed overview of the PRISM-games tool, including its modelling and property specification formalisms, and its underlying architecture and implementation. In particular, we discuss some of its key features, which include multi-objective and compositional approaches to verification and strategy synthesis. We also discuss the scalability and efficiency of the tool and give an overview of some of the case studies to which it has been applied
The Body, Thought Experiments, and Phenomenology
An explorative contribution to the ongoing discussion of thought experiments. While endorsing the majority view that skepticism about thought experiments is not well justified, in what follows we attempt to show that there is a kind of “bodiliness” missing from current accounts of thought experiments. That is, we suggest a phenomenological addition to the literature. First, we contextualize our claim that the importance of the body in thought experiments has been widely underestimated. Then we discuss David Gooding's work, which contains the only explicit recognition of the importance of the body to understanding thought experiments. Finally, we introduce a phenomenological perspective of the body, which will give us the opportunity to sketch the power and promise of a phenomenological approach to thought experiment
The Intelligence of ornaments: Exploring ornamental ways of Affordable Non-Standard Building Envelopes
The purpose of this research is to explore ornamental patterns which can be used to enhance materials characteristics in low-cost building envelopes. We use standard building materials (sheets of cross-laminated timber) and develop a parametric design framework for the assembly. Existing rules of ornamental geometry are applied to a parametric controlled structural model so as to endow the building parts both with stability and aesthetics. The concepts of mass customization and “File to factory” support the digital fabrication of a non-repetitive pattern in façade construction and lead to reduced construction costs and building time
Parametrics of Movable Polyhedral Models in Performative Architecture
We present a parametrical approach to movable polyhedral models. Based on polyhedral geometry the whole structure consisting of an interconnected series of prisms (with dual spherical joints) can move 3-dimensionally. The principles of polyhedral geometry allow constraint movements of the prisms with a certain degree of freedom. We use these geometrical principles to open and close façades for ventilation or structures for shading control superimposed on building envelopes. The different groups of regular polyhedra in the Euclidean 3-space and their specific topological types will be discussed in order to choose the appropriate model and showe geometrical theory of movable polyhedral models can be successfully applied to performative architecture
Full Scale Prototyping – Logistic and Construction Challenges Realising Digitally Designed Timber Prototypes
This paper reports on the final stage of a research project with the realization of a real scale prototype and ties an empirical finale to the project, which started as a fundamental research project three years ago. The scope of this research project was to explore new ways, how Non-Standard Architecture can be build with standard building elements using contemporary building processes and materials resource efficiently. Mass Customization and File to Factory, concepts where a continuous digital workflow is applied, were fundamental to our approach. Within this framework we developed generic parametric details and made them part of the whole process from the beginning of the design to the manufacturing. The present paper describes a strategy for the assembly of a large prototype, consisting of approximately 50 flat timber panels that are being assembled to a structure of the size of a small house. The paper focuses especially on the customized falsework, we designed for the construction of the prototype, which became a crucial part of the assembling process besides the assembly of the actual prototype
Modulation of metal-azolate frameworks for the tunable release of encapsulated glycosaminoglycans
Glycosaminoglycans (GAGs) are biomacromolecules necessary for the regulation of different biological functions. In medicine, GAGs are important commercial therapeutics widely used for the treatment of thrombosis, inflammation, osteoarthritis and wound healing. However, protocols for the encapsulation of GAGs in MOFs carriers are not yet available. Here, we successfully encapsulated GAG-based clinical drugs (heparin, hyaluronic acid, chondroitin sulfate, dermatan sulfate) and two new biotherapeutics in preclinical stage (GM-1111 and HepSYL proteoglycan) in three different pH-responsive metal-azolate frameworks (ZIF-8, ZIF-90, and MAF-7). The resultant GAG@MOF biocomposites present significant differences in terms of crystallinity, particle size, and spatial distribution of the cargo, which influences the drug-release kinetics upon applying an acidic stimulus. For a selected system, heparin@MOF, the released therapeutic retained its antithrombotic activity while the MOF shell effectively protects the drug from heparin lyase. By using different MOF shells, the present approach enables the preparation of GAG-based biocomposites with tunable properties such as encapsulation efficiency, protection and release.Miriam de J. Velásquez-Hernández, Efwita Astria, Sarah Winkler, Weibin Liang, Helmar Wiltsche, Arpita Poddar, Ravi Shukla, Glenn Prestwich, John Paderi, Pablo Salcedo-Abraira, Heinz Amenitsch, Patricia Horcajada, Christian J. Doonan and Paolo Falcar