TY - JOUR A1 - Lindner, H. A1 - Murtazin, Ayrat A1 - Groh, S. A1 - Niemax, Kay A1 - Bogaerts, A. T1 - Simulation and experimental studies on plasma temperature, flow velocity, and injector diameter effects for an inductively coupled plasma N2 - An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., ~ 50 µm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule-of-thumb equation was extracted from the results from which the transition flow rate can be estimated for different injector diameters and different injector gas compositions. PY - 2011 DO - https://doi.org/10.1021/ac201699q SN - 0003-2700 SN - 1520-6882 VL - 83 IS - 24 SP - 9260 EP - 9266 PB - American Chemical Society CY - Washington, DC AN - OPUS4-25605 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gschwind, S. A1 - Flamigni, L. A1 - Koch, J. A1 - Borovinskaya, O. A1 - Groh, S. A1 - Niemax, Kay A1 - Günther, D. T1 - Capabilities of inductively coupled plasma mass spectrometry for the detection of nanoparticles carried by monodisperse microdroplets N2 - Recently, first analyses of single sub-micrometre particles, embedded in liquid droplets, by inductively coupled plasma optical emission spectrometry (ICP-OES) with a size-equivalent detection limit of several hundred nanometres were reported.1,2 To achieve lower detection limits which might allow for the analysis of particles in the nanometre size range a more sensitive technique such as mass spectrometry (MS) is required. Various modifications of particle delivery and data acquisition systems commonly used were carried out to install a setup adequate for ICP-MS detection. These modifications enabled us to supply droplets generated by a commercial microdroplet generator (droplet size: 30–40 µm) with nearly 100% efficiency and high uniformity to the ICP. Analyses were performed using both standard solutions of dissolved metals at concentrations of 1 (Ag), 2 (Au), 5 (Au), or 10 (Cu) mg L-1 and highly diluted suspensions of gold and silver nanoparticles with sizes below 110 nm. In doing so, detection efficiencies of 10-6 counts per atom could be achieved while size-related limits of quantification were found to be 21 nm and 33 nm for gold and silver, respectively. Furthermore, the advantages of utilizing microdroplet generators vs. conventional nebulizers for nanoparticle analyses by ICP-MS are discussed. PY - 2011 DO - https://doi.org/10.1039/c0ja00249f SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 6 SP - 1166 EP - 1174 PB - Royal Society of Chemistry CY - London AN - OPUS4-25606 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulz, Wencke A1 - Nofz, Marianne A1 - Kranzmann, Axel A1 - Schorr, S. T1 - Performance of Protection Coatings during Oxyfuel Combustion Condition T2 - DMG-Sektionstreffen "Angewandte Mineralogie in Technik und Umwelt" (AMITU) und "Physik, Chemie und Kristallographie der Minerale" (PCKM) CY - Bad Münster, Germany DA - 2011-02-23 PY - 2011 AN - OPUS4-25592 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Glass Transition of Ultrathin Films from Main Chain Polymers T2 - Symposium University Leuven CY - Leuven, Belgium DA - 2011-12-15 PY - 2011 AN - OPUS4-25620 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Raedel, Martina A1 - Bücker, Michael A1 - Torge, Manfred T1 - Adhesives for Stained Glass Windows - Development of a New System for Wide Cracks T2 - CCI Symposium 2011: Adhesives and Consolidants for Conservation CY - Ottawa, Canada DA - 2011-10-17 PY - 2011 AN - OPUS4-25665 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Raedel, Martina A1 - Bücker, Michael A1 - Sabel, Martin T1 - Korrosionsschutz für farbig gefasste Eisen - und Gusseisenobjekte T2 - 45. Treffen der ARGE Korrosion/Restaurierung der GfKORR CY - Bochum, Germany DA - 2011-11-14 PY - 2011 AN - OPUS4-25666 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mathejczyk, J. A1 - Pauli, Jutta A1 - Dullin, C. A1 - Napp, J. A1 - Tietze, L.-F. A1 - Kessler, H. A1 - Resch-Genger, Ute A1 - Alves, F. T1 - Spectroscopically well-characterized RGD optical probe as a prerequisite for lifetime-gated tumor imaging N2 - Labeling of RGD peptides with near-infrared fluorophores yields optical probes for noninvasive imaging of tumors overexpressing ανβ3 integrins. An important prerequisite for optimum detection sensitivity in vivo is strongly absorbing and highly emissive probes with a known fluorescence lifetime. The RGD-Cy5.5 optical probe was derived by coupling Cy5.5 to a cyclic arginine–glycine–aspartic acid–D-phenylalanine–lysine (RGDfK) peptide via an aminohexanoic acid spacer. Spectroscopic properties of the probe were studied in different matrices in comparison to Cy5.5. For in vivo imaging, human glioblastoma cells were subcutaneously implanted into nude mice, and in vivo fluorescence intensity and lifetime were measured. The fluorescence quantum yield and lifetime of Cy5.5 were found to be barely affected on RGD conjugation but dramatically changed in the presence of proteins. By time domain fluorescence imaging, we demonstrated specific binding of RGD-Cy5.5 to glioblastoma xenografts in nude mice. Discrimination of unspecific fluorescence by lifetime-gated analysis further enhanced the detection sensitivity of RGD-Cy5.5-derived signals. We characterized RGD-Cy5.5 as a strongly emissive and stable probe adequate for selective targeting of ανβ3 integrins. The specificity and thus the overall detection sensitivity in vivo were optimized with lifetime gating, based on the previous determination of the probés fluorescence lifetime under application-relevant conditions. KW - Time domain near-infrared fluorescence (NIRF) imaging KW - Fluorescence KW - Lifetime KW - Quantum yield KW - RGD-Cy5.5 KW - Spectroscopic analysis PY - 2011 DO - https://doi.org/10.2310/7290.2011.00018 SN - 1535-3508 SN - 1536-0121 VL - 10 IS - 6 SP - 469 EP - 480 PB - Decker CY - Hamilton, Ont. AN - OPUS4-25711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maul, Ronald A1 - Kittler, Katrin A1 - Koch, Matthias A1 - Nehls, Irene T1 - Bakterielle Migranten - Algentoxine als neue Herausforderung in der Umweltanalytik N2 - Bioaktive Sekundärstoffe aus Cyanobakterien stellen eine Quelle für pharmazeutisch interessante Wirkstoffkandidaten wie auch eine Herausforderung für die Umwelt- und Lebensmittelanalytik dar. Die Identifizierung ist allerdings nicht trivial. KW - Cyanotoxine KW - Analytik PY - 2011 SN - 0344-1733 SN - 1610-8256 IS - August SP - 56 EP - 58 PB - Vogel CY - Würzburg AN - OPUS4-25733 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dahmen-Levison, U. A1 - Maul, Ronald T1 - Mykotoxin-Bestimmung - jetzt auch vollautomatisch N2 - Überall, wo sich Schimmel bildet, können hochgiftige Mykotoxine entstehen, besorgniserregende Gifte für Mensch und Tier. Ungefähr ein Viertel der Weltnahrungsproduktion ist mit diesen schädlichen Stoffen infizier!, so die Ernährung- und Landwirtschaftsorganisation FAQ. Lebensmittel wie Getreide, Mais und Nüsse, die in grollen Mengen verarbeitet werden, sind ein idealer Nährboden für die Bildung von Mykotoxinen und können bereits vor der eigentlichen Verarbeitung kontaminiert sein. Eine Kontrolle der Lebensmittellieferungen ist also aus Sicherheitsgründen unerlässlich, denn schon geringe Mengen infizierter Lebensmittel können ganze Bestände vergiften. Aufwendige Laborverfahren, die extern von geschultem Fachpersonal durchgeführt werden und daher mehrere Tage dauern, bedeuten hohe Kosten für die verarbeitende Industrie. Die Aokin AG aus Berlin hat mit der Automatisierung des „aokinmycontrol-Systems den Analyseprozess industrietauglich gemacht. PY - 2011 SN - 0027-2949 VL - 148 IS - 12 SP - 386 EP - 390 PB - Schäfer CY - Detmold AN - OPUS4-25734 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grasse, Fabian A1 - Trappe, Volker A1 - Hickmann, Stefan T1 - Zustandsüberwachung von Rotorblättern - Konzeptstudie mittels Bauteilkomponentenversuch T2 - 29. Vortrags- und Diskussionstagung Werkstoffprüfung 2011 CY - Berlin, Germany DA - 2011-12-01 PY - 2011 AN - OPUS4-25696 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -