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Lack of social fairness and increasing legal and regulatory obligations for traceability along the supply chain cause companies to face complex challenges. As a promising technology for supply chains, blockchain has the potential to address these challenges. This research focuses on governance for resilience in information systems for supply chain consortia. As instantiation, we aim to develop a governance model for blockchain-based traceability systems in supply chain consortia within an agricultural environment. To set a foundation and narrow down the research interests, within this article, we utilized a design science research approach to elicit seven tentative design principles (DP) for an agricultural supply chain consortia governance model using blockchain-based traceability systems. Drawing on existing literature and expert interviews requirements, we identified the design principle of data, legislation and regulation, roles and responsibilities, decisions, decisions rights, decision management, system as a service, social - environment and fairness, as well as an incentive system. The elaborated DP can be used as a foundation for researchers and practitioners to design a governance model, including roles, rules, incentives, structures, and processes with associated possible alternatives.

Internationale katholische Zeitschrift Communio, Bd. 20 Nr. 4 (1991): Internationale katholische Zeitschrift Communio, Band 20, Heft 4

Internationale katholische Zeitschrift Communio, Bd. 24 Nr. 2 (1995): Internationale katholische Zeitschrift Communio, Band 24, Heft 2

Internationale katholische Zeitschrift Communio, Bd. 23 Nr. 5 (1994): Internationale katholische Zeitschrift Communio, Band 23, Heft 5

Internationale katholische Zeitschrift Communio, Bd. 26 Nr. 1 (1997): Internationale katholische Zeitschrift Communio, Band 26, Heft 1

Internationale katholische Zeitschrift Communio, Bd. 28 Nr. 6 (1999): Internationale katholische Zeitschrift Communio, Band 28, Heft 6

Internationale katholische Zeitschrift Communio, Bd. 18 Nr. 4 (1989): Internationale katholische Zeitschrift Communio, Band 18, Heft 4

Internationale katholische Zeitschrift Communio, Bd. 20 Nr. 3 (1991): Internationale katholische Zeitschrift Communio, Band 20, Heft 3

This thesis evaluates the accessibility of predicting the dissolution properties of crystals of active pharmaceutical ingredients (API) from their molecular structure on the example of aspirin. Starting from the atomistic description of the molecular interactions, a multiscale approach is followed to bridge the gap from molecular to macroscopic simulation techniques. The techniques applied are molecular dynamics, kinetic Monte Carlo simulations with molecular resolution, and approaches based on continuously formulated mass transfer equations. The successful prediction of face-specific dissolution velocities is validated by comparison with literature data and experimental assessment of aspirin dissolution using an interferometer. Die Dissertation beschäftigt sich mit der Vorhersagbarkeit der Auflösung pharmazeutischer Kristalle am Beispiel von Aspirin auf Basis deren molekularen Struktur. Angefangen von der atomistischen Beschreibung der molekularen Wechselwirkungen wird über einen Multiskalenansatz die Brücke zur makroskopischen Modellierung geschlagen. Die angewendeten Simulationsmethoden umfassen molekulardynamische Simulationen, kinetische Monte Carlo Techniken und Ansätze basierend auf den Gleichungen des klassischen Stofftransportes. Die erfolgreiche Vorhersage von flächenspezifischen Auflösungsgeschwindigkeiten wird durch eine Validierung der Modelle anhand von Literaturdaten und der experimentellen Bestimmung der Kristallauflösung in einem Interferometer gezeigt.

Precipitated calcium carbonate (PCC) is a synthetic mineral widely used in various technologies, mainly as multifunctional filler or pigment (paper, plastics, pharmaceuticals, foods). The application of PCC strongly depends on its morphology and size distribution. The control and design of a desired crystal morphology and size can be achieved by employing specific additives during crystal growth processes. The organic- mediated crystal growth control of calcium carbonate is also important in biomineralization. Experimental studies have shown that small organic molecules, such as dicarboxylates or amino acids, can be used as effective regulators of calcite crystal morphology. Previous experimental results indicated specific interactions of tartaric acid with newly stabilized {; ; 1-10}; ; calcite surfaces, thus modulating the crystal morphology.1 However, the atomic-level mechanisms remain unclear. Molecular dynamics (MD) simulations can provide useful information at this level. Recent simulation studies have mainly focused on better understanding of the most stable rhombohedral (104) calcite face/solution interface, seldom including the presence of organics. 2, 3 In this work, the adsorption behavior of tartrate on calcite surfaces was studied employing MD simulations to understand additive-mediated crystal growth. The free energy landscapes for the adsorption and desorption of tartrate are calculated using metadynamics4. By this approach, the adsorption energetics of favourable conformations, orientations and positions of the tartrate near the (104) and (1-10) calcite surfaces was determined. The obtained results provided a molecular-level explanation of the experimentally observed stabilized exposure of {; ; 1- 10}; ; surfaces during calcite growth. Reorientation and conformational change of tartrate as well as interfacial water molecules played a significant role. The simulations showed that tartrate preferentially adsorbed directly to the (1-10) calcite surface, whereas tartrate was more loosely adsorbed on the (104) surface by both direct and solvent-mediated binding. The (1-10) geometry of calcite surface sites closely matches the structure of tartrate, with a specific role of carboxylate and hydroxyl groups in recognising the calcium and carbonate ions, respectively. The results indicated that preorganization of both hydroxyl and carboxylate functional groups plays a major role in the strength of the interactions and hence in the expression of the effects in calcite morphological appearance. Preferential adsorption of tartrate on {; ; 1-10}; ; surfaces could stabilize these, otherwise unstable, faces and thus inhibit crystal growth in {; ; 1-10}; ; directions. Our future work will focus on simulating the growth from supersaturated solutions of specific fast-growing calcite faces, such as (1-10), in the presence of organic additives. References [1] Ukrainczyk, M., Stelling, J., Vučak, M., Neumann T., J. Cryst. Growth 2013, 369, 21–31. [2] Ratieri, P., Gale, J.G., Quigley, D., Rodger, P.M., J. Phys. Chem. C, 2010, 114, 5997–6010. [3] Shen, J., Li, C. van der Vegt, N., Peter, C. J. Phys. Chem.C 2013, 117, 6904–6913. [4] Barducci, A., Bonomi, M., Parrinello, M. Wiley Interdiscip. Rev. Comput. Mol. Sci. 2011, 1, 826– 843.