The behavior of mixtures of 1-octanol with water with different molar ratios confined inside the mesoporous silica SBA-15 was investigated by a combination of solid-state NMR spectroscopy and molecular dynamics (MD) simulations. Two-dimensional 1H–29Si FSLG-HETCOR NMR spectra revealed the orientation of 1-octanol relative to the pore walls. These arrangements are in good agreement with the preferred structures found by MD. In addition, MD simulations also shed light on molecular orientations and interactions in the pore center region, which are not resolvable by solid-state NMR.

In this work, it is shown how solid-state NMR combined with dynamic nuclear polarization (DNP) can be employed as a powerful tool to selectively enhance the spectral intensity of functional groups on the surface of cellulose fibers in paper materials. As a model system, a poly(benzyl methacrylate) (PBEMA)-functionalized paper material is chosen that contains hydrophobic and hydrophilic domains. Detailed analysis of the DNP NMR data and of T 1ρ data suggests that inhomogeneous 1 H− 1 H spin diffusion is responsible for the observed differences in signal enhancement. These findings are fundamental for structural understanding of complex paper substrates for fluid transport or sensor materials.

A series of novel functionalized mesoporous silica-based materials with well-defined pore diameters, surface functionalization and surface morphology is synthesized by co-condensation or grafting techniques and characterized by solid-state NMR spectroscopy, DNP enhanced solid state-NMR and thermodynamic techniques. These materials are employed as host-systems for small-guest molecules like water, small alcohols, carbonic acids, small aromatic molecules, binary mixtures and others. The phase-behavior of these confined guests is studied by combinations of one dimensional solid-state NMR techniques (1H MAS,2H-line shape analysis,13C CPMAS) and two-dimensional correlation experiments like1H-29Si- solid-state HETCOR.

The structure and surface functionalization of biologically relevant silica‐based hybrid materials was investigated by 2D solid‐state NMR techniques combined with dynamic nuclear polarization (DNP). This approach was applied to a model system of mesoporous silica, which was modified through in‐pore grafting of small peptides by solid‐phase peptide synthesis (SPPS). To prove the covalent binding of the peptides on the surface, DNP‐enhanced solid‐state NMR was used for the detection of 15N NMR signals in natural abundance. DNP‐enhanced heterocorrelation experiments with frequency switched Lee–Goldburg homonuclear proton decoupling (1H–13C and 1H–15N CP MAS FSLG HETCOR) were performed to verify the primary structure and configuration of the synthesized peptides. 1H FSLG spectra and 1H‐29Si FSLG HETCOR correlation spectra were recorded to investigate the orientation of the amino acid residues with respect to the silica surface. The combination of these NMR techniques provides detailed insights into the structure of amino acid functionalized hybrid compounds and allows for the understanding for each synthesis step during the in‐pore SPPS.

In this study, a high-frequency floating-type memristor emulator has been presented. The proposed emulator circuit uses a current conveyor transconductance amplifier, second generation current conveyor, three resistors and a grounded capacitor. The presented floating-type memristor can be configured in both incremental and decremental configurations and performs well up to 5 MHz. The equivalent memristor equation is verified by theoretical analysis of the proposed circuit which also includes non-ideal analysis. The theoretical proposition has been verified through personal simulation program with integrated circuit emphasis simulations using TSMC 0.25 μm complementary metal oxide semiconductor technology parameters. Moreover, non-volatility and Monte Carlo simulation have been performed to check the robustness of the circuit. The effectiveness of the presented memristor emulator design has been verified by printed circuit board prototype using commonly available integrated circuits AD844 and CA3080. The experimental results are included, which show good agreement with the theoretical and simulation results. To test the functionalities of the proposed designs, their applications as parallel and serial combinations, high-pass filter and Chua's oscillator have been presented.

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Surface enhanced solid-state NMR by dynamic nuclear polarization (DNP SENS) enables the characterization of the inner-pore surface functionalization of porous etched ion-track membranes exhibiting low specific surface areas compared to typical SBA- or MCM-type mesoporous silica materials. The membranes were conformally coated with a 5 nm thin SiO2 layer by atomic layer deposition. This layer was subsequently modified by aminopropyl silane linkers that allow further functionalization via the terminal amine group. The results evidence that in principle DNP SENS is a capable tool to analyze more complex porous systems, e.g. bioinspired functional etched ion-track membranes down to the molecular level. These results are relevant also for single nanopore systems, for which a direct analysis of the channel surface functionalization is not feasible by classical characterization methods. The applicability of DNP SENS to complex porous systems requires the optimization of the sample preparation and measurement parameters.

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