TY - JOUR A1 - Jäger, Christian A1 - Groom, N. S. A1 - Bowe, Elizabeth A. A1 - Horner, A. A1 - Davies, M. Elisabeth A1 - Murray, Rachel C. A1 - Duer, M. J. T1 - Investigation of the Nature of the Protein-Mineral Interface in Bone by Solid-State NMR N2 - Hydrogen-bearing species in the bone mineral environment were investigated using solid-state NMR spectroscopy of powdered bone, deproteinated bone, and B-type carbonated apatite. Using magic-angle spinning and cross-polarization techniques three types of structurally-bound water were observed in these materials. Two of these water types occupy vacancies within the apatitic mineral crystal in synthetic carbonated apatite and deproteinated bone and serve to stabilize these defect-containing crystals. The third water was observed at the mineral surface in unmodified bone but not in deproteinated bone, suggesting a role for this water in mediating mineral-organic matrix interactions. Direct evidence of monohydrogen phosphate in a 1H NMR spectrum of unmodified bone is presented for the first time. We obtained clear evidence for the presence of hydroxide ion in deproteinated bone by 1H MAS NMR. A 1H-31P heteronuclear correlation experiment provided unambiguous evidence for hydroxide ion in unmodified bone as well. Hydroxide ion in both unmodified and deproteinated bone mineral was found to participate in hydrogen bonding with neighboring water molecules and ions. In unmodified bone mineral hydroxide ion was found, through a 1H-31P heteronuclear correlation experiment, to be confined to a small portion of the mineral crystal, probably the internal portion. KW - NMR KW - Bone KW - Protein-mineral-interface PY - 2005 DO - https://doi.org/10.1529/biophysj.105.070243 SN - 0897-4756 SN - 1520-5002 VL - 17 IS - 12 SP - 3059 EP - 3061 PB - American Chemical Society CY - Washington, DC AN - OPUS4-11010 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Seto, J. A1 - Ma, Y. A1 - Davis, S.A. A1 - Meldrum, F. A1 - Gourrier, A. A1 - Kim, Y.-Y. A1 - Schilde, U. A1 - Sztucki, M. A1 - Burghammer, M. A1 - Maltsev, Sergey A1 - Jäger, Christian A1 - Cölfen, H. T1 - Structure-property relationships of a biological mesocrystal in the adult sea urchin spine N2 - Structuring over many length scales is a design strategy widely used in Nature to create materials with unique functional properties. We here present a comprehensive analysis of an adult sea urchin spine, and in revealing a complex, hierarchical structure, show how Nature fabricates a material which diffracts as a single crystal of calcite and yet fractures as a glassy material. Each spine comprises a highly oriented array of Mg-calcite nanocrystals in which amorphous regions and macromolecules are embedded. It is postulated that this mesocrystalline structure forms via the crystallization of a dense array of amorphous calcium carbonate (ACC) precursor particles. A residual surface layer of ACC and/or macromolecules remains around the nanoparticle units which creates the mesocrystal structure and contributes to the conchoidal fracture behavior. Nature’s demonstration of how crystallization of an amorphous precursor phase can create a crystalline material with remarkable properties therefore provides inspiration for a novel approach to the design and synthesis of synthetic composite materials. KW - Calcium carbonate biomineralization KW - Echinoderm skeleton KW - Hierarchical structuring KW - Mesocrystal KW - Skeletal elements PY - 2012 DO - https://doi.org/10.1073/pnas.1109243109 SN - 0027-8424 SN - 1091-6490 VL - 109 IS - 10 SP - 3699 EP - 3704 PB - National Academy of Sciences CY - Washington, DC AN - OPUS4-27726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, T. A1 - Uhlmann, E. A1 - Häcker, Ralf A1 - Jäger, M. A1 - Rauch, H. A1 - Kondas, J. A1 - Brach, K. A1 - Singh, R. T1 - Evaluation of electric conductivity and mechanical load capacity of copper deposits for application in large winding components for electrical high-voltage machines made with cold spray additive manufacturing N2 - In line with the industrial trend of additive manufacturing, cold spray as a non-laser-based process is becoming increasingly important for many fields of application. For the evaluation of additive manufacturing of winding components made of copper for large electrical high-voltage machines, material and component properties such as electrical conductivity, mechanical load capacity and the component size that can be produced are of particular importance. In this context, the cold spray process offers advantages over laser-based additive manufacturing processes such as laser powder bed fusion (LPBF) or laser cladding by using the kinetic energy of the copper powder particles to generate particle cohesion. To investigate the electrical conductivity as well as the mechanical load capacity of cold spray parts, specimens were machined out of cold sprayed bulk copper deposits. The characteristic values were obtained with regard to the direction of deposition, which is defined by the direction of the robot’s movement. Thus, for the investigation of the component properties, specimens were provided that had been produced both longitudinally and transversely as well as orthogonally to the direction of deposition. The results of the investigations show that both the electrical conductivity and the mechanical load capacity of the specimen have a strong preferential direction of the specimen orientation with respect to the direction of deposition. Furthermore, it could be shown that by increasing the deposition height, there is an increasing oxygen content in the sample material, combined with increasingly significant defect networks. These effects have a negative impact on the electrical conductivity as well as on the mechanical load capacity. As a conclusion, further need for investigation is identified in the optimization of the process parameters as well as in the deposition strategy for the additive manufacturing of large-volume components with cold spray. T2 - ITSC 2022 CY - Wien, Austria DA - 04.05.2022 KW - Cold Spray KW - Electrical conductivity KW - Copper powder particles KW - Large electrical high-voltage machine PY - 2022 SP - 1 EP - 7 AN - OPUS4-56108 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wise, Erica R. A1 - Maltsev, Sergey A1 - Davies, M.E. A1 - Duer, M.J. A1 - Jäger, Christian A1 - Loveridge, N. A1 - Murray, Rachel C. A1 - Reid, D.G. T1 - The Organic - Mineral Interface in Bone Is Predominantly Polysaccharide KW - NMR KW - Bone KW - Mineral-organic interface PY - 2007 DO - https://doi.org/10.1021/cm702054c SN - 0897-4756 SN - 1520-5002 VL - 19 IS - 21 SP - 5055 EP - 5057 PB - American Chemical Society CY - Washington, DC AN - OPUS4-17583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karrasch, Andrea A1 - Jäger, Christian A1 - Karakawa, M. A1 - Nakatsubo, F. A1 - Potthast, A. A1 - Rosenau, T. T1 - Solid-state NMR studies of methyl celluloses. Part 1: regioselectively substituted celluloses as standards for establishing an NMR data basis N2 - Three methyl celluloses with completely uniform substitution pattern, 2-O-methyl cellulose (1), 3-O-methyl cellulose (2) and 6-O-methyl cellulose (3), were prepared according to the cationic ring opening polymerization approaches starting from substituted 1,2,4-orthopivalate derivatives of D-glucose. These samples allowed for the first time to sort out the methyl substitution effects on solid-state NMR chemical shifts and relaxation. Dipolar dephasing experiments allowed the detection and assignment (1H, 13C) of the methyl groups. In 1 and 2, these resonances overlapped with those of C-6, whereas in 3, the methyl signal experienced a low-field shift into the region of C-2,3,5. 13C T1 experiments were used to verify different relaxation behavior of the carbon sites, particularly the short relaxation time of at the carbon substitution site next to the methyl groups. This effect was used to unambiguously identify the 13C chemical shifts of the carbons carrying the methoxyl substituent, although they overlap with all resonances in the C-2,3,5 region. The data obtained for the standard samples with uniform substitution will now be used as the basis for determining methylation patterns and substitution degree in commercial methyl celluloses. KW - Methyl cellulose KW - Solid-state NMR KW - CPMAS NMR KW - Substituent distribution KW - Substitution pattern KW - Cationic ring opening polymerization KW - Methylation PY - 2009 DO - https://doi.org/10.1007/s10570-008-9247-z SN - 0969-0239 SN - 1572-882X VL - 16 SP - 129 EP - 137 PB - Chapman & Hall CY - London AN - OPUS4-18913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Debatin, F. A1 - Thomas, A. A1 - Kelling, A. A1 - Hedin, N. A1 - Bacsik, Z. A1 - Senkovska, I. A1 - Kaskel, S. A1 - Junginger, M. A1 - Müller, H. A1 - Schilde, U. A1 - Jäger, Christian A1 - Friedrich, A. A1 - Holdt, H.-J. T1 - In situ synthesis of an imidazolate-4-amide-5-imidate ligand and formation of a microporous zinc-organic framework with H2-and CO2-storage ability KW - Metal-organic framework KW - Synthesis KW - XRD KW - FTIR KW - NMR KW - Gas sorption KW - Microporous materials KW - N,O ligands KW - Solvothermal synthesis PY - 2010 DO - https://doi.org/10.1002/anie.200906188 SN - 1433-7851 SN - 1521-3773 SN - 0570-0833 VL - 49 IS - 7 SP - 1258 EP - 1262 PB - Wiley-VCH CY - Weinheim AN - OPUS4-21132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholz, G. A1 - Krahl, Thoralf A1 - Ahrens, M. A1 - Martineau, C. A1 - Buzaré, J.Y. A1 - Jäger, Christian A1 - Kemnitz, E. T1 - 115In and 19F MAS NMR study of (NH4)3InF6 phases N2 - This study presents for the first time an NMR spectroscopic characterization of the room and high temperature phases of (NH4)3InF6 using 19F and 115In as probe nuclei. The reversible phase transition to the cubic phase at 353 K was followed by MAS NMR in situ. Static NMR experiments of the room temperature phase and MAS NMR experiments of the high temperature phase allowed the determination of the NMR parameters of both nuclei. Finally, the scalar In–F coupling, rarely observed in solid state NMR, is evidenced in both room and high temperature phases of (NH4)3InF6, and measured in the high temperature phase. KW - (NH4)3InF6 KW - 115In and 19F solid state NMR KW - XRD PY - 2011 DO - https://doi.org/10.1016/j.jfluchem.2011.01.010 SN - 0022-1139 SN - 1873-3328 VL - 132 IS - 4 SP - 244 EP - 249 PB - Elsevier CY - Amsterdam AN - OPUS4-23475 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartoszek, M. A1 - Eckelt, R. A1 - Jäger, Christian A1 - Kosslick, H. A1 - Pawlik, Alf A1 - Schulz, A. T1 - Mesoporous silica-aluminas derived from precipitation: a study of the acidity, textural properties and catalytic performance KW - Silica-alumina KW - Solid state NMR KW - Acidity KW - Silicates KW - Tetrahedral aluminium PY - 2009 DO - https://doi.org/10.1007/s10853-009-3580-y SN - 0022-2461 SN - 1573-4803 VL - 44 IS - 24 SP - 6629 EP - 6636 PB - Springer Science + Business Media B.V. CY - Norwell, Mass. AN - OPUS4-20462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pawlik, Alf A1 - König, R. A1 - Scholz, G. A1 - Kemnitz, E. A1 - Brunklaus, G. A1 - Bertmer, M. A1 - Jäger, Christian T1 - Access to local structures of HS-AIF3 and its precursor determined by high-resolution solid-state NMR KW - Aluminium fluoride KW - 27Al NMR KW - MQMAS KW - Amorphous materials KW - Catalysts PY - 2009 DO - https://doi.org/10.1021/jp904626k SN - 1932-7447 SN - 1089-5639 VL - 113 IS - 38 SP - 16674 EP - 16680 PB - Soc. CY - Washington, DC AN - OPUS4-20463 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jäger, Christian A1 - Duer, M. J. T1 - Solid-state NMR: a tool for probing the protein-mineral interface and other structures in bone T2 - EUROMAR 2005/EENC 2005 CY - Veldhoven, Netherlands DA - 2005-07-03 PY - 2005 AN - OPUS4-7551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jäger, Christian A1 - Welzel, T. A1 - Meyer-Zaika, W. A1 - Epple, M. T1 - A solid-state NMR investigation of the structure of nanocrystalline hydroxyapatite N2 - Nanocrystalline hydroxyapatite (HAp) prepared by a precipitation route was investigated. The X-ray diffraction (XRD) powder patterns of the elongated nanocrystals with a typical diameter of about 10 nm and length of 30-50 nm (by transmission electron microscopy (TEM)) revealed the presence of HAp with significantly broadened XRD reflections. However, Ca deficiency was found, as the Ca/P ratio was 1.5 only (so-called calcium-deficient hydroxyapatite (CDHA)), and not 1.67. This Ca deficiency of nanocrystalline HAp is explained using NMR. It is shown unambiguously that (i) the nanocrystals consist of a crystalline core and a (disordered) surface region with a relative phosphate content of about 1:1, (ii) the crystalline core is HAp, and (iii) the surface region is dominated by hydrogen phosphate anions (with no hydroxyapatite-like structural motif) and structural water (hydrate). From the relative phosphate content and taking into account the crystal shape, the thickness of the surface layer along the main crystal axis could be estimated to be about 1 nm, and the average chemical composition of the surface layer has been determined. Finally, a Ca/P ratio of 1.52 was estimated from the NMR data that compares well with the value of 1.51 from chemical analysis. The important consequences are that the surface of nanocrystalline HAp has nothing in common with the bulk composition and that the chemistry of such materials (e.g. the binding of protein molecules to phosphate surfaces) must be reconsidered. KW - NMR KW - H-1 KW - P-31 KW - Biomineralization KW - Hydroxyapatite KW - Calcium phosphate KW - Nanoparticles PY - 2006 DO - https://doi.org/10.1002/mrc.1774 SN - 0749-1581 SN - 1097-458X VL - 44 IS - 6 SP - 573 EP - 580 PB - Wiley CY - Chichester AN - OPUS4-12366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nassif, N. A1 - Pinna, N. A1 - Gehrke, N. A1 - Antonietti, M. A1 - Jäger, Christian A1 - Cölfen, H. T1 - Amorphous layer around aragonite platelets in nacre KW - Nacre KW - NMR KW - Aragonite KW - Amorphous Surface KW - Protein binding PY - 2005 SN - 0027-8424 SN - 1091-6490 VL - 102 IS - 36 SP - 12653 EP - 12655 PB - National Academy of Sciences CY - Washington, DC AN - OPUS4-11009 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -