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Description, Highly efficient optimal control experiments for routine studies of solid proteins by NMR using various MAS frequencies., Dipolar recoupling is a central concept in the nuclear magnetic resonance spectroscopy of powdered solids and is used to establish correlations between different nuclei by magnetization transfer. The efficiency of conventional cross-polarization methods is low because of the inherent radio frequency (rf) field inhomogeneity present in the magic angle spinning (MAS) experiments and the large chemical shift anisotropies at high magnetic fields. Very high transfer efficiencies can be obtained using optimal control–derived experiments. These sequences had to be optimized individually for a particular MAS frequency. We show that by adjusting the length and the rf field amplitude of the shaped pulse synchronously with sample rotation, optimal control sequences can be successfully applied over a range of MAS frequencies without the need of reoptimization. This feature greatly enhances their applicability on spectrometers operating at differing external fields where the MAS frequency needs to be adjusted to avoid detrimental resonance effects.

We present a toolbox for the rapid characterisation of powdered samples of paramagnetic metal–organic frameworks at natural abundance by 1H-detected solid-state NMR. Very fast MAS rates at room and cryogenic temperatures and a set of tailored radiofrequency irradiation schemes help overcome the sensitivity and resolution limits often associated with the characterisation of MOF materials. We demonstrate the approach on DUT-8(Ni), a framework containing Ni2+ paddle-wheel units which can exist in two markedly different architectures. Resolved 1H and 13C resonances of organic linkers are detected and assigned in few hours with only 1–2 mg of sample at natural isotopic abundance, and used to rapidly extract information on structure and local internal dynamics of the assemblies, as well as to elucidate the metal electronic properties over an extended temperature range. The experiments disclose new possibilities for describing local and global structural changes and correlating them to electronic and magnetic properties of the assemblies. Wir präsentieren neue Werkzeuge für die schnelle Charakterisierung pulverförmiger Proben paramagnetischer MOFs in natürlicher Häufigkeit mittels 1H-detektierter Festkörper-NMR-Spektroskopie. Sehr schnelle MAS-Raten bei Raumtemperatur und tiefen Temperaturen sowie eine Auswahl maßgeschneiderter Pulssequenzen werden genutzt, um die Beschränkungen hinsichtlich Empfindlichkeit und Auflösung zu beheben, von denen die Charakterisierung neuer MOFs oft begleitet ist. Wir demonstrieren diesen Ansatz an DUT-8(Ni), einem MOF mit Ni2+-Schaufelrad-Einheiten, das in zwei deutlich unterschiedlichen Strukturen existiert. Gut aufgelöste 1H- und 13C-Resonanzen der organischen Linker werden mit nur 1–2 mg Probe in natürlicher Häufigkeit binnen weniger Stunden erhalten, zugeordnet, und genutzt, um schnell Informationen über die Struktur und die lokale interne Dynamik der Verbindungen zu erlangen und um die elektronischen Eigenschaften des Metalls in einem weiten Temperaturbereich aufzuklären.

We present a toolbox for the rapid characterisation of powdered samples of paramagnetic metal–organic frameworks at natural abundance by 1H-detected solid-state NMR. Very fast MAS rates at room and cryogenic temperatures and a set of tailored radiofrequency irradiation schemes help overcome the sensitivity and resolution limits often associated with the characterisation of MOF materials. We demonstrate the approach on DUT-8(Ni), a framework containing Ni2+ paddle-wheel units which can exist in two markedly different architectures. Resolved 1H and 13C resonances of organic linkers are detected and assigned in few hours with only 1–2 mg of sample at natural isotopic abundance, and used to rapidly extract information on structure and local internal dynamics of the assemblies, as well as to elucidate the metal electronic properties over an extended temperature range. The experiments disclose new possibilities for describing local and global structural changes and correlating them to electronic and magnetic properties of the assemblies. Wir präsentieren neue Werkzeuge für die schnelle Charakterisierung pulverförmiger Proben paramagnetischer MOFs in natürlicher Häufigkeit mittels 1H-detektierter Festkörper-NMR-Spektroskopie. Sehr schnelle MAS-Raten bei Raumtemperatur und tiefen Temperaturen sowie eine Auswahl maßgeschneiderter Pulssequenzen werden genutzt, um die Beschränkungen hinsichtlich Empfindlichkeit und Auflösung zu beheben, von denen die Charakterisierung neuer MOFs oft begleitet ist. Wir demonstrieren diesen Ansatz an DUT-8(Ni), einem MOF mit Ni2+-Schaufelrad-Einheiten, das in zwei deutlich unterschiedlichen Strukturen existiert. Gut aufgelöste 1H- und 13C-Resonanzen der organischen Linker werden mit nur 1–2 mg Probe in natürlicher Häufigkeit binnen weniger Stunden erhalten, zugeordnet, und genutzt, um schnell Informationen über die Struktur und die lokale interne Dynamik der Verbindungen zu erlangen und um die elektronischen Eigenschaften des Metalls in einem weiten Temperaturbereich aufzuklären.

Debris flow events yield a threat to different components of mountainous environments not only as the result of the process evolution but of the interaction with human systems and their coupled vulnerabilities. A variety of models exists for characterising the hazard that the different mass-flow phenomena present. In the case of dynamic run-out models, they are able to forecast the propagation of material after the initial failure and to delineate the zone where the elements at risk will suffer an impact with a certain level of intensity. The results of these models are an appropriate input for vulnerability and risk assessments. An important feature of using run-out models is the possibility to perform forward analyses and forecast changes in hazards. However, still most of the work using these models is based on the calibration of parameters doing a back calculation of past events. Given the number of unknown parameters and the fact that most of the rheological parameters cannot be measured in the laboratory or in the field, it is very difficult to parameterize the run-out models. For this reason the application of run-out models is mostly used for back analysis of past events and very few studies attempts to achieve a forward modelling with the available run-out models. A reason for this is the substantial degree of uncertainty that still characterizes the definition of the run-out model parameters. Since a variety of models exists for simulating mass-flows and for identifying the intensity of the hazardous phenomena, it is important to assess these models, perform a parameterization and reduce their uncertainties. This will enable to improve the understanding to assess the hazard and will provide the link with vulnerability curves that will lead eventually to generate risk curves and quantify the risk.

Risk assessment is the process of determining the likelihood or threat of a damage, injury, liability, loss, or other negative occurrence that is caused by external or internal vulnerabilities and that may be neutralized through preventive action. More precisely, risk assessment is the systematic prospective analysis aimed at defining, as quantitatively as possible, the potential loss of life, personal injury, economic loss, and property damage resulting from natural and/or anthropogenic hazards, by assessing the exposure and vulnerability of people and property to those hazards. The risk assessment procedure, developed in the Mountain Risks project, is based on the following five steps: (1) Identification and analysis of the specific types of hazards that could affect a territory and its community; (2) Definition of the spatial and temporal likelihood of the damaging events considered in the analysis as well as their magnitude; (3) Inventory of the assets and study of the social and economic features of the study areas; (4) Assessment of vulnerability, evaluating all the hazard consequences for each dimension composing the systems at risk (physical/functional, economic, socio-cultural, ecological/environmental and; political/institutional); (5) Evaluation of the prospective cost of damage or costs avoided through mitigation strategies. Vulnerability assessment plays a crucial role both in 'translating' the assessed level of hazard into an estimated level of risk and in providing leading information in mitigation planning processes and emergency management strategies. Under this perspective, it is really difficult, or even impossible, to address risk assessment without assessing vulnerability first and it appears unquestionable that a multi-disciplinary approach is required in vulnerability assessment studies. In this section, the different components (dimensions) of vulnerability are analyzed, both theoretically and practically, and then different methodological approaches, applications and solutions are provided.

Cyclam (1,4,8,11-tetraazacyclotetradecane) derivatives are widely used for various purposes. In a medicine they are applied as ligands for radiometals applied as diagnostic or therapeutic agents against tumours, hypoxic brain tissues etc. In this thesis a new method for asymmetric cyclam derivati- ves preparation was developed. New cyclam derivatives with trifluoroethyl groups were prepared too. Paramagnetic metal complexes with these fluori- nated ligands can be used as contrast agents for 19 F-MRI. Keywords: Cyclam; Non-symmetric protection; Contrast agents; Trifluoroethylamines; Paramagnetic relaxation; 19 F-MRI.

Because of an indisputable pharmacological advatages of radiometal-labeled compounds, a purpose of this work it to design and synthesize a new chelatation system for copper(II) complexation. The solution properties of the ligand and copper complex are also studied, as well as its ability for binding a targeting molecule.

Title: Theoretical investigation of 27 Al chemical shifts dependence on water amount and temperature in zeolite MFI Abstract: This bachelor thesis explores 27 Al NMR spectra in zeolite MFI and investigates the impact of several factors on the chemical shielding values, including water loading, temperature, and the relative positions of aluminum pairs. Various machine learning-based methods for calculating chemical shift are evaluated. Molecular dynamics simulations with neural network potentials are used to simulate experimental conditions. Neural network potentials offer a highly efficient means of calculating energy with a significant speed-up of approximately 1000 times faster than density functional theory, while maintaining a high level of accuracy. This study is the first to examine 27 Al NMR under operando conditions, with a focus on the experimentally relevant amount of water. Keywords: 27 Al NMR, machine learning, zeolites, MFI, operando conditions, neural network potentials

19 F MRI contrast agents are relatively new, developing field of medical and chemical sciences. In this Theses, based on previous results in this area, new type of Ni2+ complex with possible 19 F MRI applications was synthesized and characterized by relaxometric measurements.

Fluorinated coordination compounds having short nuclear spin relaxation times due to the presence of paramagnetic metal ions close to 19 F nuclei are suitable/potential contrast agents in 19 F MRI. This thesis deals with the preparation of a ligand based on 1,4,7-triazacyclononane (TACN) with pendant arms containing fluorine atoms. The coordination properties to transition metal ions were studied and prepared complexes were characterised. Measured values of longitudinal relaxation times of 19 F NMR signal indicate that the chosen concept is promising for further use in 19 F MRI, especially for the Co(II) complex. Keywords: 19 F MRI, contrast agent, trifluoroethyl phosphinic acid, TACN, paramagnetic ion, relaxation time, effective magnetic moment