TY - GEN A1 - Neuhaus, B. A1 - Allspach, A. A1 - Bartsch, P. A1 - Burckhardt, D. A1 - Coleman, C.O. A1 - Fries, I. A1 - Fuchs, R. A1 - Gudo, M. A1 - Kotrba, M. A1 - Mentjes, M. A1 - Moore, S. A1 - Neumann, D. A1 - Oberer, C. A1 - Potthast, A. A1 - Riedel, Juliane A1 - Rudolf, R. A1 - Schnalke, T. A1 - Schönbohm, D. A1 - Schuda, M. A1 - van Dam, A. A1 - Widulin, N. T1 - KUR-Projekt: Aufbau und öffentliche Kommunikation eines wissenschafts-basierten Sammlungsmanagements für naturkundliche Nasssammlungen N2 - Im Rahmen eines von der Kulturstiftung des Bundes und der Kulturstiftung der Länder geförderten Projektes zum Erhalt naturkundlicher Nasssammlungen wurden 1) der Zustand der Sammlungen bewertet (Profiling; Analyse der Vergällungsmittel), 2) über Workshops Expertenwissen in das Projekt gebracht, 3) neue archivbeständige Materialien und Managementmaßnahmen eingeführt (Borosilikat-Gläser und - Röhrchen, Augenwatte, Tefloneinlagen, Japanpapier, archivbeständige Kleber und Papier, Etikettenaufbewahrung; digitales Dichtemessgerät, Alcomon-Indikator, Kontrollintervalle), 4) Erhaltungsmaßnahmen zur langfristigen Konservierung in großem Umfange durchgeführt (Messen der Alkoholkonzentration, Umsetzen von Präparaten in geeignetere Gefäße, Wiederverschluss von Schaugläsern) und 5) Erfahrungen und Diskussionsergebnisse zusammengestellt, nicht ohne auf Wissenslücken und wünschenswerte Forschungsaspekte hinzuweisen. Das Projekt profitierte besonders von der Expertise aus den Materialwissenschaften und der Papierrestaurierung. Das Museum für Naturkunde Berlin kooperierte eng mit dem Berliner Medizinhistorischen Museum der Charité, der Zoologischen Staatssammlung München und dem Forschungsinstitut Senckenberg in Frankfurt. Letzteres Museum führte ein eigenes, themenverwandtes KUR-Projekt Restauration der Sammlungen 'Vergleichende Anatomie, Embryologie und Histologie' des Naturmuseums Senckenberg durch. KW - Nasssammlung KW - Ethanol KW - Vergällungsmittel PY - 2012 DO - https://doi.org/10.5165/hawk-hhg/epublication/44 SP - 1 EP - 32 AN - OPUS4-25491 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Musl, O. A1 - Sulaeva, I. A1 - Sumerskii, I. A1 - Mahler, A.K. A1 - Rosenau, T. A1 - Falkenhagen, Jana A1 - Potthast, A. T1 - Mapping of the Hydrophobic Composition of Lignosulfonates N2 - Lignosulfonates are industrial biorefinery products that are characterized by significant variability and heterogeneity in their structural composition. Typically, they exhibit high dispersities in molar mass (molar mass distribution-MMD) and in functionalities (functionality-type distribution - FTD), which crucially affect their material usage. In terms of FTD, state-of-the-art Lignin analytics still rely mainly on the determination of functional group contents, which are statistical averages with limited explanatory power. In contrast, our online hydrophobic interaction chromatography−size-exclusion chromatography 2D-LC approach combines the determination of both MMD and FTD in a single measurement to provide a comprehensive picture of the characteristic composition of industrial lignosulfonates information hitherto inaccessible by state-of-the-art lignin analytics. In this way, the complex inter - relationships between these two important structural parameters can be studied in an unprecedented manner. In this study, we reveal the considerable differences in terms of hydrophobic composition and its dispersity present in a range of different industrial lignosulfonates - data desperately needed in tailoring and refining of lignosulfonate composition for material usage. KW - Lignosulfonates KW - Amphiphilicity KW - Hydrophobic interaction chromatography KW - Two-dimensional chromatography (2D-LC) KW - Charge-to-size-ratio PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538612 DO - https://doi.org/10.1021/acssuschemeng.1c06469 VL - 9 IS - 49 SP - 16786 EP - 16795 PB - ASC Publications AN - OPUS4-53861 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 - Karrasch, Andrea A1 - Jäger, Christian A1 - Saake, B. A1 - Potthast, A. A1 - Rosenau, T. T1 - Solid-state NMR studies of methyl celluloses. Part 2: Determination of degree of substitution and O-6 vs. O-2/O-3 substituent distribution in commercial methyl cellulose samples N2 - Solid state NMR spectroscopy was applied to determine the overall degree of substitution (DS) and the degrees of substitution at C-6 (DSC-6) and C-2/3 (DSC-2/3). Four commercial methyl cellulose samples were used, having a DS between 0.51 and 1.96 as determined by wet-chemical analysis. The strategy and optimization of the NMR data acquisition as well as the data evaluation procedures are explained in detail. Optimization of the approach mainly comprised (a) maximizing the signal by choice of NMR probe, MAS spinning frequency and B0 field, (b) minimizing the measurement time by a Torchia-type experiment and (c) suppressing probe background by rotor-synchronized echo detection. Data evaluation used simply the integration of three different spectral ranges in the 13C NMR spectrum. The results of the experiments were in good agreement with the wet-chemical data. The NMR approach takes about the same analysis time as the conventional hydrolysis/chromatography analysis. However, it is a generally applicable and simple alternative without need for an extended sample preparation which is most useful if wet-chemical/chromatographic analyses are undesired or unavailable. Further studies have to concentrate on the validation of the analytical method and application to a larger sample array. KW - Methyl cellulose KW - Solid-state NMR KW - 13C CPMAS NMR KW - Rotor-synchronized echo sequence KW - Substituent distribution KW - Substitution pattern KW - Degree of substitution PY - 2009 DO - https://doi.org/10.1007/s10570-009-9304-2 SN - 0969-0239 SN - 1572-882X VL - 16 IS - 6 SP - 1159 EP - 1166 PB - Chapman & Hall CY - London AN - OPUS4-21130 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adorjan, I. A1 - Rosenau, Th. A1 - Potthast, A. A1 - Kosma, P. A1 - Mereiter, K. A1 - Pauli, Jutta A1 - Jäger, Christian T1 - Crystal and molecular structure of methyl 4-O-methyl-beta-D-ribo-hex-3-ulopyranoside N2 - Methyl 4-O-methyl-?-Image-ribo-hex-3-ulopyranoside (2), a model compound for partially oxidized anhydroglucose units in cellulose, was crystallized from CHCl3/n-hexane by vapor diffusion to give colorless plates. Crystal structure determination revealed the monoclinic space group P21 with Z=2C8H14O6 and unit cell parameters of a=8.404(2), b=4.5716(10), c=13.916(3) Å, and ?=107.467(4)°. The structure was solved by direct methods and refined to R=0.0476 for 1655 reflections and 135 parameters. The hexulopyranoside occurs in a distorted chair conformation. Both hydroxyls are involved in hydrogen bonding and form zigzag bond chains along the b-axis. One of the two hydrogen bonds is bifurcated. The solid-state 13C NMR spectrum of 2 exhibits eight carbon resonances, with well-separated signals for the two methoxyls (1-OMe: 55.72 ppm, 4-OMe: 61.25 ppm) and a keto resonance with relatively large downfield shift (206.90 ppm). Differences in the C-4 and the methoxyls’ chemical shifts in the solid and liquid states were found KW - Crystal structure KW - Solid-state NMR KW - Cellulose KW - Carbonyl groups PY - 2004 DO - https://doi.org/10.1016/j.carres.2004.01.006 SN - 0008-6215 SN - 1873-426X VL - 339 IS - 4 SP - 795 EP - 799 PB - Elsevier CY - Amsterdam AN - OPUS4-5341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mackie, I.D. A1 - Röhrling, J. A1 - Gould, R.O. A1 - Pauli, Jutta A1 - Jäger, Christian A1 - Walkinshaw, M. A1 - Potthast, A. A1 - Rosenau, Th. A1 - Kosma, P. T1 - Crystal and molecular structure of methyl 4-O-methyl-beta-D-glucopyranosyl-(1->4)-beta-D-glucopyranoside N2 - The cellulose model compound methyl 4-O-methyl-?-Image-glucopyranosyl-(1?4)-?-Image-glucopyranoside (6) was synthesised in high overall yield from methyl ?-Image-cellobioside. The compound was crystallised from methanol to give colourless prisms, and the crystal structure was determined. The monoclinic space group is P21 with Z=2 and unit cell parameters a=6.6060 (13), b=14.074 (3), c=9.3180 (19) Å, ?=108.95(3)°. The structure was solved by direct methods and refined to R=0.0286 for 2528 reflections. Both glucopyranoses occur in the 4C1 chair conformation with endocyclic bond angles in the range of standard values. The relative orientation of both units described by the interglycosidic torsional angles [? (O-5?---C-1?---O-4---C-4) -89.1°, phi (C-1?---O-4---C-4---C-5) -152.0°] is responsible for the very flat shape of the molecule and is similar to those found in other cellodextrins. Different rotamers at the exocyclic hydroxymethyl group for both units are present. The hydroxymethyl group of the terminal glucose moiety displays a gauche–trans orientation, whereas the side chain of the reducing unit occurs in a gauche–gauche conformation. The solid state 13C NMR spectrum of compound 6 exhibits all 14 carbon resonances. By using different cross polarisation times, the resonances of the two methyl groups and C-6 carbons can easily be distinguished. Distinct differences of the C-1 and C-4 chemical shifts in the solid and liquid states are found. KW - Crystal structure KW - Cellulose KW - Methyl cellobioside KW - Solid state NMR PY - 2002 DO - https://doi.org/10.1016/S0008-6215(01)00299-3 SN - 0008-6215 SN - 1873-426X VL - 337 IS - 2 SP - 161 EP - 166 PB - Elsevier CY - Amsterdam AN - OPUS4-11023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -