TY - JOUR A1 - Derrien, Thibault A1 - Koter, Robert A1 - Krüger, Jörg A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Bonse, Jörn T1 - Plasmonic formation mechanism of periodic 100-nm-structures upon femtosecond laser irradiation of silicon in water JF - Journal of applied physics N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of silicon by multiple (N = 100) linearly polarized Ti:sapphire femtosecond laser pulses (duration τ = 30 fs, center wavelength λ0 ~ 790 nm) is studied experimentally in air and water environment. The LIPSS surface morphologies are characterized by scanning electron microscopy and their spatial periods are quantified by two-dimensional Fourier analyses. It is demonstrated that the irradiation environment significantly influences the periodicity of the LIPSS. In air, so-called low-spatial frequency LIPSS (LSFL) were found with periods somewhat smaller than the laser wavelength (ΛLSFL ~ 0.7 × λ0) and an orientation perpendicular to the laser polarization. In contrast, for laser processing in water a reduced ablation threshold and LIPSS with approximately five times smaller periods ΛLIPSS ~ 0.15 × λ0 were observed in the same direction as in air. The results are discussed within the frame of recent LIPSS theories and complemented by a thin film based surface plasmon polariton model, which successfully describes the tremendously reduced LIPSS periods in water. PY - 2014 DO - https://doi.org/10.1063/1.4887808 SN - 0021-8979 SN - 1089-7550 VL - 116 IS - 7 SP - 074902-1 EP - 074902-8 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-31209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Koter, Robert A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Femtosecond laser-induced periodic surface structures on steel and titanium alloy for tribological applications JF - Applied physics A N2 - Laser-induced periodic surface structures (LIPSS, ripples) were generated on stainless steel (100Cr6) and titanium alloy (Ti6Al4V) surfaces upon irradiation with multiple femtosecond laser pulses (pulse duration 30 fs, central wavelength 790 nm). The experimental conditions (laser fluence, spatial spot overlap) were optimized in a sample-scanning geometry for the processing of large surface areas (5 × 5 mm²) covered homogeneously by the nanostructures. The irradiated surface regions were subjected to white light interference microscopy and scanning electron microscopy revealing spatial periods around 600 nm. The tribological performance of the nanostructured surface was characterized by reciprocal sliding against a ball of hardened steel in paraffin oil and in commercial engine oil as lubricants, followed by subsequent inspection of the wear tracks. For specific conditions, on the titanium alloy a significant reduction of the friction coefficient by a factor of more than two was observed on the laser-irradiated (LIPSS-covered) surface when compared to the non-irradiated one, indicating the potential benefit of laser surface structuring for tribological applications. PY - 2014 DO - https://doi.org/10.1007/s00339-014-8229-2 SN - 0947-8396 VL - 117 IS - 1 SP - 103 EP - 110 PB - Springer CY - Berlin AN - OPUS4-31450 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Derrien, Thibault A1 - Krüger, Jörg A1 - Itina, T.E. A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Bonse, Jörn T1 - Rippled area formed by surface plasmon polaritons upon femtosecond laser double-pulse irradiation of silicon: the role of carrier generation and relaxation processes JF - Applied physics A N2 - The formation of laser-induced periodic surface structures (LIPSS, ripples) upon irradiation of silicon with multiple irradiation sequences consisting of femtosecond laser pulse pairs (pulse duration 150 fs, central wavelength 800 nm) is studied numerically using a rate equation system along with a two-temperature model accounting for one- and two-photon absorption and subsequent carrier diffusion and Auger recombination processes. The temporal delay between the individual equal-energy fs-laser pulses was varied between 0 and ~4 ps for quantification of the transient carrier densities in the conduction band of the laser-excited silicon. The results of the numerical analysis reveal the importance of carrier generation and relaxation processes in fs-LIPSS formation on silicon and quantitatively explain the two time constants of the delay-dependent decrease of the low spatial frequency LIPSS (LSFL) area observed experimentally. The role of carrier generation, diffusion and recombination is quantified individually. PY - 2014 DO - https://doi.org/10.1007/s00339-013-8205-2 SN - 0947-8396 VL - 117 IS - 1 SP - 77 EP - 81 PB - Springer CY - Berlin AN - OPUS4-31451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Implications of transient changes of optical and surface properties of solids during femtosecond laser pulse irradiation to the formation of laser-induced periodic surface structures JF - Applied surface science N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of silicon wafer surfaces by linearly polarized Ti:sapphire femtosecond laser pulses (pulse duration 130 fs, central wavelength 800 nm) is studied experimentally and theoretically. In the experiments, so-called low-spatial frequency LIPSS (LSFL) were found with periods smaller than the laser wavelength and an orientation perpendicular to the polarization. The experimental results are analyzed by means of a new theoretical approach, which combines the widely accepted LIPSS theory of Sipe et al. with a Drude model, in order to account for transient (intra-pulse) changes of the optical properties of the irradiated materials. It is found that the LSFL formation is caused by the excitation of surface plasmon polaritons, SPPs, once the initially semiconducting material turns to a metallic state upon formation of a dense free-electron-plasma in the material and the subsequent interference between its electrical field with that of the incident laser beam resulting in a spatially modulated energy deposition at the surface. Moreover, the influence of the laser-excited carrier density and the role of the feedback upon the multi-pulse irradiation and its relation to the excitation of SPP in a grating-like surface structure is discussed. KW - Femtosecond laser ablation KW - Laser-induced periodic surface structures KW - (LIPSS) KW - Optical properties KW - Surface plasmon polaritons KW - Semiconductors KW - Silicon PY - 2011 DO - https://doi.org/10.1016/j.apsusc.2010.11.059 SN - 0169-4332 SN - 1873-5584 VL - 257 IS - 12 SP - 5420 EP - 5423 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-23309 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Rosenfeld, A. A1 - Krüger, Jörg ED - Panchenko, V. ED - Mourou, G. ED - Zheltikov, A. M. T1 - Femtosecond laser-induced periodic surface structures: recent approaches to explain their sub-wavelength periodicities T2 - LAT 2010 - International Conference on Lasers, Applications, and Technologies (Proceedings of SPIE) N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of semiconductors and dielectrics by linearly polarized high-intensity Ti:sapphire fs-laser pulses (τ ~100 fs, λ ~800 nm) is studied experimentally and theoretically. In the experiments, two different types of LIPSS exhibiting very different spatial periods are observed (socalled LSFL – low spatial frequency LIPSS, and HSFL - high spatial frequency LIPSS), both having a different dependence on the incident laser fluence and pulse number per spot. The experimental results are analyzed by means of a new theoretical approach, which combines the generally accepted LIPSS theory of J. E. Sipe and co-workers [Phys. Rev. B 27, 1141-1154 (1983)] with a Drude model, in order to account for transient changes of the optical properties of the irradiated materials. The joint Sipe-Drude model is capable of explaining numerous aspects of fs-LIPSS formation, i.e., the orientation of the LIPSS, their fluence dependence as well as their spatial periods. The latter aspect is specifically demonstrated for silicon crystals, which show experimental LSFL periods Λ somewhat smaller than λ. This behaviour is caused by the excitation of surface plasmon polaritons, SPP, (once the initially semiconducting material turns to a metallic state upon formation of a dense free-electron-plasma in the material) and the subsequent interference between its electrical fields with that of the incident laser beam, resulting in a spatially modulated energy deposition at the surface. Upon multi-pulse irradiation, a feedback mechanism, caused by the redshift of the resonance in a grating-assisted SPP excitation, is further reducing the LSFL spatial periods. The SPP-based mechanism of LSFL successfully explains the remarkably large range of LSFL periods between ~0.6 λ and λ. T2 - LAT 2010 - International Conference on Lasers, Applications, and Technologies CY - Kazan, Russia DA - 23.08.2010 KW - Femtosecond laser ablation KW - Laser-induced periodic surface structures (LIPSS) KW - Surface plasmon polaritons KW - Second harmonic generation (SHG) KW - Silicon KW - Semiconductors KW - Dielectrics PY - 2011 DO - https://doi.org/10.1117/12.879813 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 7994 SP - 79940M-1 EP - 79940M-10 CY - Bellingham, USA AN - OPUS4-23291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rohloff, M. A1 - Das, S.K. A1 - Höhm, S. A1 - Grunwald, R. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Formation of laser-induced periodic surface structures on fused silica upon multiple cross-polarized double-femtosecond-laser-pulse irradiation sequences JF - Journal of applied physics N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of fused silica with multiple irradiation sequences consisting of five Ti:sapphire femtosecond (fs) laser pulse pairs (150 fs, 800 nm) is studied experimentally. A Michelson interferometer is used to generate near-equal-energy double-pulse sequences with a temporal pulse delay from -20 to +20 ps between the cross-polarized individual fs-laser pulses (~0.2 ps resolution). The results of multiple double-pulse irradiation sequences are characterized by means of Scanning Electron and Scanning Force Microscopy. Specifically in the sub-ps delay domain striking differences in the surface morphologies can be observed, indicating the importance of the laser-induced free-electron plasma in the conduction band of the solids for the formation of LIPSS. KW - Atomic force microscopy KW - Conduction bands KW - High-speed optical techniques KW - Laser beam effects KW - Scanning electron microscopy KW - Silicon compounds KW - Surface morphology PY - 2011 DO - https://doi.org/10.1063/1.3605513 SN - 0021-8979 SN - 1089-7550 VL - 110 IS - 1 SP - 014910-1 - 014910-4 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-24049 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Höhm, S. A1 - Herzlieb, M. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Laser-induced periodic surface structures on fused silica upon cross-polarized two-color double-fs-pulse irradiation JF - Applied surface science N2 - The dynamics of the formation of laser-induced periodic surface structures (LIPSS) on fused silica upon irradiation with linearly polarized fs-laser pulses (50 fs pulse duration) is studied by cross-polarized two-color double-fs-pulse experiments. In order to analyze the relevance of temporally distributed energy deposition in the early stage of LIPSS formation, a Mach-Zehnder interferometer was used for generating multiple double-pulse sequences at two different wavelengths (400 and 800 nm). The inter-pulse delay between the individual cross-polarized pulses of each sequence was systematically varied in the sub-ps range and the resulting LIPSS morphologies were characterized by scanning electron microscopy. It is found that the polarization of the first laser pulse arriving to the surface determines the orientation and the periodicity of the LIPSS. These two-color experiments further confirm the importance of the ultrafast energy deposition to the silica surface for LIPSS formation, particularly by the first laser pulse of each sequence. The second laser pulse subsequently reinforces the previously seeded spatial LIPSS characteristics (period, orientation). KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser ablation KW - Double-pulse experiments KW - Ultrafast optical techniques KW - Mach-Zehnder interferometer PY - 2015 DO - https://doi.org/10.1016/j.apsusc.2014.09.101 SN - 0169-4332 SN - 1873-5584 VL - 336 SP - 39 EP - 42 PB - North-Holland CY - Amsterdam AN - OPUS4-32860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Koter, Robert A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Tribological performance of femtosecond laser-induced periodic surface structures on titanium and a high toughness bearing steel JF - Applied surface science N2 - Laser-induced periodic surface structures (LIPSS, ripples) were processed on steel (X30CrMoN15-1) and titanium (Ti) surfaces by irradiation in air with linear polarized femtosecond laser pulses with a pulse duration of 30 fs at 790 nm wavelength. For the processing of large LIPSS covered surface areas (5 mm × 5 mm), the laser fluence and the spatial spot overlap were optimized in a sample-scanning geometry. The laser-processed surfaces were characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). Spatial LIPSS periods between 450 and 600 nm were determined. The nanostructured surface regions were tribologically tested under reciprocal sliding conditions against a 10-mm diameter ball of hardened 100Cr6 steel. Paraffin oil and engine oil were used as lubricants for 1000 sliding cycles at 1 Hz with a normal load of 1.0 N. The corresponding wear tracks were analyzed by OM and SEM. In particular cases, the laser-generated nanostructures endured the tribological treatment. Simultaneously, a significant reduction of the friction coefficient and the wear was observed in the laser-irradiated (LIPSS-covered) areas when compared to the non-irradiated surface. The experiments reveal the potential benefit of laser surface structuring for tribological applications. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser processing KW - Tribology KW - Metals PY - 2015 DO - https://doi.org/10.1016/j.apsusc.2014.08.111 SN - 0169-4332 SN - 1873-5584 VL - 336 SP - 21 EP - 27 PB - North-Holland CY - Amsterdam AN - OPUS4-32861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Laser-induced periodic surface structures on titanium upon single- and two-color femtosecond double-pulse irradiation JF - Optics express N2 - Single- and two-color double-fs-pulse experiments were performed on titanium to study the dynamics of the formation of laser-induced periodic surface structures (LIPSS). A Mach-Zehnder inter-ferometer generated polarization controlled (parallel or cross-polarized) double-pulse sequences in two configurations – either at 800 nm only, or at 400 and 800 nm wavelengths. The inter-pulse delays of the individual 50-fs pulses ranged up to some tens of picoseconds. Multiple of these single- or two-color double-fs-pulse sequences were collinearly focused by a spherical mirror to the sample surface. In both experimental configurations, the peak fluence of each individual pulse was kept below its respective ablation threshold and only the joint action of both pulses lead to the formation of LIPSS. Their resulting characteristics were analyzed by scanning electron microscopy and the periods were quantified by Fourier analyses. The LIPSS periods along with the orientation allow a clear identification of the pulse which dominates the energy coupling to the material. A plasmonic model successfully explains the delay-dependence of the LIPSS on titanium and confirms the importance of the ultrafast energy deposition stage for LIPSS formation. PY - 2015 DO - https://doi.org/10.1364/OE.23.025959 SN - 1094-4087 VL - 23 IS - 20 SP - 25959 EP - 25971 PB - Optical Society of America CY - Washington, DC AN - OPUS4-34354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, A. A1 - Zellmer, S. A1 - Riesselmann, B. A1 - Krüger, Simone A1 - Raspe, Tina A1 - Schwarz, Silke A1 - Stahn, Sebastian A1 - Urban, Klaus T1 - Carbon monoxide release curves from measurements during indoor charcoal burning: systematic research on toxic levels for humans JF - Clinical toxicology N2 - The Federal Institute for Risk Assessment (BfR) DocCenter has received more and more reports of cases of carbon monoxide (CO) poisoning, some even with fatal outcomes after indoor use of charcoal grills. CO is odorless, colorless, non-irritant and does not produce any other warning effect perceptible to humans. The BfR and the Federal Institute for Materials Research and Testing (BAM) have completed a cooperative research project to investigate the toxic concentrations of CO that are reached when charcoal grills or open fires are used indoors. KW - Toxicity KW - Indoor charcoal burning PY - 2014 DO - https://doi.org/10.3109/15563650.2014.906213 SN - 1556-3650 VL - 52 IS - 4 SP - 351 PB - Informa Healthcare CY - Philadelphia, Pa. AN - OPUS4-34582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bonse, Jörn A1 - Höhm, S. A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Koter, Robert A1 - Marschner, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg ED - König, K. ED - Ostendorf, A. T1 - Femtosecond laser-induced surface nanostructures for tribological applications T2 - Optically induced nanostructures: Biomedical and technical applications N2 - Laser-induced periodic surface structures (LIPSS) were generated on two types of steel (100Cr6, X30CrMoN15-1) and two types of titanium (Ti, Ti6A14V) surfaces upon irradiation with multiple linear polarized femtosecond laser pulses in air environment (pulse duration 30 fs, central wavelength 790 nm, pulse repetition rate 1 kHz, Gaussian beam shape). Teh conditions (laser fluence, spatial spot overlap) were optimized in a sample-scanning geometry for the processing of large surface areas covered homogeneously by two different types of LIPSS - either near wavelength or sub-100 nm structures. The tribological performance of the nanostructured surfaces was characterized under reciprocating sliding at 1 Hz against a ball of hardened steel using different lubricants and normal forces. After 1000 cycles the corresponding wear tracks were characterized by optical and scanning electron microscopy. For specific conditions, the wear was strongly reduced and laser-generated nanostructures endured the tribological treatment. Simultaneously, a significant reduction of the friction coefficient was observed in the laser-irradiated LIPSS-covered areas, indicating the benefit of laser surface structuring for tribological applications. The spatially Gaussian shaped beam used for the laser processing was transformed via beam shaping into a top hat distribution at the surface of the samples for optimization. The tribological performance of the laser-induced nanostructures is discussed on the basis of different physical and chemical mechanisms. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-332647 SN - 978-3-11-033718-1 SN - 978-3-11-035432-4 DO - https://doi.org/10.1515/9783110354324-011 SP - Chapter 7, 141 EP - 156 PB - De Gruyter AN - OPUS4-33264 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Höhm, S. A1 - Herzlieb, M. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Femtosecond laser-induced periodic surface structures on silicon upon polarization controlled two-color double-pulse irradiation JF - Optics express N2 - Two-color double-fs-pulse experiments were performed on silicon wafers to study the temporally distributed energy deposition in the formation of laser-induced periodic surface structures (LIPSS). A Mach-Zehnder interferometer generated parallel or cross-polarized double-pulse sequences at 400 and 800 nm wavelength, with inter-pulse delays up to a few picoseconds between the sub-ablation 50-fs-pulses. Multiple two-color double-pulse sequences were collinearly focused by a spherical mirror to the sample. The resulting LIPSS characteristics (periods, areas) were analyzed by scanning electron microscopy. A wavelength-dependent plasmonic mechanism is proposed to explain the delay-dependence of the LIPSS. These two-color experiments extend previous single-color studies and prove the importance of the ultrafast energy deposition for LIPSS formation. PY - 2015 DO - https://doi.org/10.1364/OE.23.000061 SN - 1094-4087 VL - 23 IS - 1 SP - 61 EP - 71 PB - Optical Society of America CY - Washington, DC AN - OPUS4-32405 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Höhm, S. A1 - Rohloff, M. A1 - Krüger, Jörg A1 - Bonse, Jörn A1 - Rosenfeld, A. ED - Sakabe, S. ED - Lienau, C. ED - Grunwald, R. T1 - Formation of laser-induced periodic surface structures (LIPSS) on dielectrics and semiconductors upon double-femtosecond laser pulse irradiation sequences T2 - Progress in nonlinear nano-optics N2 - The formation of laser-induced periodic surface structures (LIPSS) on different materials (silicon, fused silica, quartz) with linearly polarized fs-laser irradiation is studied experimentally. In dielectrics, the importance of transient excitation stages in the LIPSS formation is demonstrated by using (multiple) cross-polarized double-fs-laser-pulse irradiation sequences. A characteristic decrease of the spatial LIPSS periods is observed for double-pulse delays of less than 2 ps along with a characteristic 90°-rotation of the LIPSS orientation. PY - 2015 SN - 978-3-319-12216-8 SN - 978-3-319-12217-5 DO - https://doi.org/10.1007/978-3-319-12217-5_5 SN - 2192-1970 N1 - Serientitel: Nano-Optics and Nanophotonics – Series title: Nano-Optics and Nanophotonics SP - Chapter 5, 85 EP - 99 PB - Springer AN - OPUS4-32541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Höhm, S. A1 - Kirner, Sabrina V. A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Laser-induced periodic surface structures — a scientific evergreen JF - IEEE Journal of Selected Topics in Quantum Electronics N2 - Laser-induced periodic surface structures (LIPSS, ripples) are a universal phenomenon and can be generated on almost any material upon irradiation with linearly polarized radiation. With the availability of ultrashort laser pulses, LIPSS have gained an increasing attraction during the past decade, since these structures can be generated in a simple single-step process, which allows a surface nanostructuring for tailoring optical, mechanical, and chemical surface properties. In this study, the current state in the field of LIPSS is reviewed. Their formation mechanisms are analyzed in ultrafast time-resolved scattering, diffraction, and polarization constrained double-pulse experiments. These experiments allow us to address the question whether the LIPSS are seeded via ultrafast energy deposition mechanisms acting during the absorption of optical radiation or via self-organization after the irradiation process. Relevant control parameters of LIPSS are identified, and technological applications featuring surface functionalization in the fields of optics, fluidics, medicine, and tribology are discussed. KW - Laser ablation KW - Nanostructures KW - Surface functionalization KW - Surface texture KW - Laser-induced periodic surface structures (LIPSS) PY - 2017 DO - https://doi.org/10.1109/JSTQE.2016.2614183 SN - 1077-260X SN - 1558-4542 VL - 23 IS - 3 SP - 9000615 PB - IEEE AN - OPUS4-38633 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Laser-induced periodic surface structures on zinc oxide crystals upon two-colour femtosecond double-pulse irradiation JF - Physica Scripta N2 - In order to study the temporally distributed energy deposition in the formation of laser-induced periodic surface structures (LIPSS) on single-crystalline zinc oxide (ZnO), two-colour double-fs-pulse experiments were performed. Parallel or cross-polarised double-pulse sequences at 400 and 800 nm wavelength were generated by a Mach–Zehnder interferometer, exhibiting inter-pulse delays up to a few picoseconds between the sub-ablation 50-fs-pulses. Twenty two-colour double-pulse sequences were collinearly focused by a spherical mirror to the sample surface. The resulting LIPSS periods and areas were analysed by scanning electron microscopy. The delay-dependence of these LIPSS characteristics shows a dissimilar behaviour when compared to the semiconductor silicon, the dielectric fused silica, or the metal titanium. A wavelength-dependent plasmonic mechanism is proposed to explain the delay-dependence of the LIPSS on ZnO when considering multi-photon excitation processes. Our results support the involvement of nonlinear processes for temporally overlapping pulses. These experiments extend previous two-colour studies on the indirect semiconductor silicon towards the direct wide band-gap semiconductor ZnO and further manifest the relevance of the ultrafast energy deposition for LIPSS formation. KW - Laser-induced periodic surface structures, LIPSS KW - Laser ablation KW - Surface plasmon polariton PY - 2017 DO - https://doi.org/10.1088/1402-4896/aa5578 SN - 1402-4896 SN - 0031-8949 VL - 92 IS - 3 SP - Article 034003, 1 EP - 7 PB - IOP CY - Bristol, UK AN - OPUS4-39082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mioduszewska, K. A1 - Maszkowska, J. A1 - Bialk-Bielinska, A. A1 - Krüger, Oliver A1 - Kalbe, Ute A1 - Liberek, B. A1 - Lukaszewicz, P. A1 - Stepnowski, P. T1 - The leaching behavior of cyclophosphamide and ifosfamide from soil in the presence of co-contaminant - Mixture sorption approach JF - Science of the total environment N2 - Anticancer drugs (ACDs) exhibit high biological activity, they are cytotoxic, genotoxic, and are constantly released into the environment as a result of incomplete metabolism. Consequently they pose a serious threat to the environment and human health due to their carcinogenic,mutagenic and/or reproductive toxicity properties. Knowledge of their bioavailability, including their sorption to soils and their impact on the soil–groundwater pathway, is crucial for their risk assessment. Laboratory batch and column leaching tests are important tools for determining the release potential of contaminants from soil or waste material. Batch and column tests were carried out with soils differing in physicochemical properties, each spiked with cyclophosphamide (CK) or ifosfamide (IF). Moreover, due to the fact that environmental pollutants may occur as coexisting compounds in the soil themobility evaluation for ACDs in the mixture with metoprolol (MET; β-blocker) as a co-contaminant was performed. In order to assess appropriateness, the batch and column tests were compared. The release depended on the properties of both the soil and the presence of co-contaminants. The faster release was observed for coarse-grained soil with the smallest organic matter content (MS soil: 90% decrease in concentration until liquid-to-solid ratio (L/S) of 0.3 L kg−1 for all tests' layout) than for loamy sand (LS soil: 90% decrease in concentration until ratio L/S of 0.75 L kg−1). ACDs are highly mobile in soil systems. Furthermore, the decrease of mobility of ifosfamide was observed with the presence of a co-contaminant (metoprolol) in both of the soils (in MS soil a decrease of 29%; in LS soil a decrease of 26%). The mobility of cyclophosphamide does not depend on the presence of a contaminant for MS soil, but also exhibits a decrease of 21% in LS soil. PY - 2016 DO - https://doi.org/10.1016/j.scitotenv.2015.11.002 SN - 0048-9697 SN - 1879-1026 VL - 542 SP - 915 EP - 922 PB - Elsevier CY - Amsterdam AN - OPUS4-34972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Höhm, S. A1 - Koter, Robert A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Tribological performance of sub-100-nm femtosecond laser-induced periodic surface structures on titanium JF - Applied Surface Science N2 - Sub-100-nm laser-induced periodic surface structures (LIPSS) were processed on bulk titanium (Ti) surfaces by femtosecond laser pulse irradiation in air (30 fs pulse duration, 790 nm wavelength). The laser peak fluence, the spatial spot overlap, and the number of overscans were optimized in a sample-scanning geometry in order to obtain large surface areas (5 mm × 5 mm) covered homogeneously by the LIPSS. The laser-processed regions were characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). The friction coefficient of the nanostructured surfaces was tested during 1000 cycles under reciprocal sliding conditions (1 Hz, 1.0 N normal load) against a 10-mm diameter ball of hardened 100Cr6 steel, both in paraffin oil and in engine oil used as lubricants. Subsequently, the corresponding wear tracks were qualified by OM, SEM, and energy dispersive X-ray analyses (EDX). The results of the tribological tests are discussed and compared to that obtained for near wavelength-sized fs-LIPSS, processed under somewhat different irradiation conditions. Some constraints for a beneficial effect of LIPSS on the tribological performance are provided. KW - Femtosecond laser ablation KW - Laser-induced periodic surface structures, LIPSS KW - Friction KW - Wear KW - Nanostructures KW - Surface functionalization PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0169433215026987 DO - https://doi.org/10.1016/j.apsusc.2015.11.019 SN - 0169-4332 SN - 1873-5584 VL - 374 SP - 190 EP - 196 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-35937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Höhm, S. A1 - Herzlieb, M. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Dynamics of the formation of laser-induced periodic surface structures (LIPSS) upon femtosecond two-color double-pulse irradiation of metals, semiconductors, and dielectrics JF - Applied Surface Science N2 - In order to address the dynamics and physical mechanisms of LIPSS formation for three different classes of materials (metals, semiconductors, and dielectrics), two-color double-fs-pulse experiments were performed on Titanium, Silicon and Fused Silica. For that purpose a Mach–Zehnder interferometer generated polarization controlled (parallel or cross-polarized) double-pulse sequences at 400 nm and 800 nm wavelength, with inter-pulse delays up to a few picoseconds. Multiple of these two-color double-pulse sequences were collinearly focused by a spherical mirror to the sample surfaces. The fluence of each individual pulse (400 nm and 800 nm) was always kept below its respective ablation threshold and only the joint action of both pulses lead to the formation of LIPSS. Their resulting characteristics (periods, areas) were analyzed by scanning electron microscopy. The periods along with the LIPSS orientation allow a clear identification of the pulse which dominates the energy coupling to the material. For strong absorbing materials (Silicon, Titanium), a wavelength-dependent plasmonic mechanism can explain the delay-dependence of the LIPSS. In contrast, for dielectrics (Fused Silica) the first pulse always dominates the energy deposition and LIPSS orientation, supporting a non-plasmonic formation scenario. For all materials, these two-color experiments confirm the importance of the ultrafast energy deposition stage for LIPSS formation. KW - Femtosecond laser ablation KW - Double-pulse experiments KW - Laser-induced periodic surface structures (LIPSS) KW - Mach-Zehnder interferometer KW - Ultrafast optical techniques PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0169433215031347 DO - https://doi.org/10.1016/j.apsusc.2015.12.129 SN - 0169-4332 SN - 1873-5584 VL - 374 SP - 331 EP - 338 PB - Elsevier CY - Amsterdam, Netherlands AN - OPUS4-35938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Florian, Camilo A1 - Wonneberger, R. A1 - Undisz, A. A1 - Kirner, Sabrina V. A1 - Wasmuth, Karsten A1 - Spaltmann, Dirk A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Chemical effects during the formation of various types of femtosecond laser-generated surface structures on titanium alloy JF - Applied Physics A N2 - In this contribution, chemical, structural, and mechanical alterations in various types of femtosecond laser-generated surface structures, i.e., laser-induced periodic surface structures (LIPSS, ripples), Grooves, and Spikes on titanium alloy, are characterized by various surface analytical techniques, including X-ray diffraction and glow-discharge optical emission spectroscopy. The formation of oxide layers of the different laser-based structures inherently influences the friction and wear performance as demonstrated in oil-lubricated reciprocating sliding tribological tests (RSTTs) along with subsequent elemental mapping by energy-dispersive X-ray analysis. It is revealed that the fs-laser scan processing (790 nm, 30 fs, 1 kHz) of near-wavelength-sized LIPSS leads to the formation of a graded oxide layer extending a few hundreds of nanometers into depth, consisting mainly of amorphous oxides. Other superficial fs-laser-generated structures such as periodic Grooves and irregular Spikes produced at higher fluences and effective number of pulses per unit area present even thicker graded oxide layers that are also suitable for friction reduction and wear resistance. Ultimately, these femtosecond laser-induced nanostructured surface layers efficiently prevent a direct metal-to-metal contact in the RSTT and may act as an anchor layer for specific wear-reducing additives contained in the used engine oil. KW - Laser-induced oxide layer KW - Laser-induced periodic surface strctures (LIPSS) KW - Femtosecond laser processing KW - Tribology KW - Surface processing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-505660 DO - https://doi.org/10.1007/s00339-020-3434-7 SN - 0947-8396 SN - 1432-0630 VL - 126 IS - 4 SP - 266 PB - Springer Nature Switzerland AG AN - OPUS4-50566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Beck, Uwe A1 - Krüger, A. T1 - Abschlussbericht für das Kooperationsprojekt zwischen Unternehmen und Forschungseinrichtungen (KF) - Nanoskalige Haftvermittler zur Erhöhung der Haft- bzw. Klebfestigkeit kritischer Verbundsysteme unter Verwendung von ALD-Hybridprozessen N2 - Aufzählung der wichtigsten wissenschaftlich-technischen und anderer wesentlicher Ergebnisse • ALD Abscheidungen auf Polymeren (PE, PP, PTFE) unter Atmosphärendruck und im Vakuum mit Ozon als Oxidationsmittel wurden durchgeführt: - Mit Variation der Schichtdicke - Mit Variation der Zykluszeit - Mit und ohne Ozon Vorbehandlung der Oberfläche • ALD Abscheidungen auf (PE, PP, PTFE) in Vakuum mit O2- und H2-Plasma Vorbehandlung wurden durchgeführt. - Mit Variation der Schichtdicke - Mit Variation der Zykluszeit - Mit und ohne Plasma Vorbehandlung der Oberfläche • Die ALD Prozesse wurden mit in situ Laserellipsometrie untersucht. • Die ALD Schichten wurden für die Haftfestigkeit bei der BAM ausgewerte KW - ALD-Abscheidungen KW - Plasma Vorbehandlung KW - Laserellipsometrie KW - Haftfestigkeit PY - 2017 N1 - Das Dokument unterliegt der Vertraulichkeit und kann nicht zugänglich gemacht werden - The document is subject to confidentiality restrictions and cannot be made accessible - Projektlaufzeit: 01.07.2015-30.06.2017 - Project runtime: 01.07.2015-30.06.2017 SP - 1 EP - 17 AN - OPUS4-50386 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Florian, Camilo A1 - Fischer, Daniel A1 - Freiberg, K. A1 - Duwe, M. A1 - Sahre, Mario A1 - Schneider, S. A1 - Hertwig, Andreas A1 - Krüger, Jörg A1 - Rettenmayr, M. A1 - Beck, Uwe A1 - Undisz, A. A1 - Bonse, Jörn T1 - Single Femtosecond Laser-Pulse-Induced Superficial Amorphization and Re-Crystallization of Silicon JF - Materials N2 - Superficial amorphization and re-crystallization of silicon in <111> and <100> orientation after irradiation by femtosecond laser pulses (790 nm, 30 fs) are studied using optical imaging and transmission electron microscopy. Spectroscopic imaging ellipsometry (SIE) allows fast data acquisition at multiple wavelengths and provides experimental data for calculating nanometric amorphous layer thickness profiles with micrometric lateral resolution based on a thin-film layer model. For a radially Gaussian laser beam and at moderate peak fluences above the melting and below the ablation thresholds, laterally parabolic amorphous layer profiles with maximum thicknesses of several tens of nanometers were quantitatively attained. The accuracy of the calculations is verified experimentally by high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (STEM-EDX). Along with topographic information obtained by atomic force microscopy (AFM), a comprehensive picture of the superficial re-solidification of silicon after local melting by femtosecond laser pulses is drawn. KW - Femtosecond laser KW - Silicon KW - Amorphization KW - Crystallization KW - Spectroscopic imaging ellipsometry PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523687 UR - https://www.mdpi.com/1996-1944/14/7/1651 DO - https://doi.org/10.3390/ma14071651 SN - 1996-1944 VL - 14 IS - 7 SP - 1651-1 EP - 1651-21 PB - MDPI AG CY - Basel, Switzerland AN - OPUS4-52368 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Rosenfeld, A. A1 - Höhm, S. A1 - Krüger, Jörg A1 - Bonse, Jörn ED - Reedijk, J. T1 - Dynamics of ultrashort double-pulse laser ablation of solid surfaces T2 - Reference Module in Chemistry, Molecular Sciences and Chemical Engineering, Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry N2 - Given their unique properties, ultrashort laser pulses with durations in the femtosecond to picosecond range currently open new avenues in the field of laser materials processing, resulting in groundbreaking new applications based on laser-induced surface functionalization. This article reviews the usability of temporally distributed energy deposition via double-pulse irradiation in applications based on laser ablation. This includes simple new techniques for surface nanostructuring and improved sensitivities in spectroscopic material analyses. KW - Carrier excitation KW - Double-pulse KW - Interferometer KW - Laser ablation KW - Femtosecond PY - 2017 UR - https://www.sciencedirect.com/science/article/pii/B9780124095472141277 SN - 978-0-12-409547-2 DO - https://doi.org/10.1016/B978-0-12-409547-2.14127-7 SP - 1 EP - 10 PB - Elsevier AN - OPUS4-43594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tsibidis, G. D. A1 - Mimidis, A. A1 - Skoulas, E. A1 - Kirner, Sabrina V. A1 - Krüger, Jörg A1 - Bonse, Jörn A1 - Stratakis, E. T1 - Modelling periodic structure formation on 100Cr6 steel after irradiation with femtosecond-pulsed laser beams JF - Applied Physics A N2 - We investigate the periodic structure formation upon intense femtosecond pulsed irradiation of chrome steel (100Cr6) for linearly polarised laser beams. The underlying physical mechanism of the laser-induced periodic structures is explored, their spatial frequency is calculated and theoretical results are compared with experimental observations. The proposed theoretical model comprises estimations of electron excitation, heat transfer, relaxation processes, and hydrodynamics-related mass transport. Simulations describe the sequential formation of sub-wavelength ripples and supra-wavelength grooves. In addition, the influence of the laser wavelength on the periodicity of the structures is discussed. The proposed theoretical investigation offers a systematic methodology towards laser processing of steel surfaces with important applications. KW - Laser-induced periodic surface structures KW - Femtosecond laser ablation KW - Steel PY - 2018 UR - https://link.springer.com/article/10.1007/s00339-017-1443-y DO - https://doi.org/10.1007/s00339-017-1443-y SN - 0947-8396 SN - 1432-0630 VL - 124 IS - 1 SP - 27, 1 EP - 13 PB - Springer-Verlag AN - OPUS4-43626 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Birgit Angelika A1 - Pentzien, Simone A1 - Conradi, Andrea A1 - Krüger, Jörg A1 - Roth, C. A1 - Beier, O. A1 - Hartmann, A. A1 - Grünler, B. T1 - Decontamination of biocidal loaded wooden artworks by means of laser and plasma processing T2 - Proceedings of the International Conference LACONA XI N2 - Many wooden artworks are contaminated by DDT (dichlorodiphenyltrichloroethane) as a result of a surface treatment by means of the liquid preservative Hylotox-59©. It was used until the end of the 1980s. DDT crystal structures are formed on the wood surfaces by the "blooming" of chlorine compounds. In addition to an aesthetic disturbance, it is assumed that DDT represents a health risk. Even decades after applying, the toxins in the wood preservatives are still detectable because they are of low volatility in many wood samples. Contaminated waste wood with natural biocide ageing, gilded and wood carved elements of an old picture frame and wooden samples with paint layers were provided by the Schlossmuseum Sondershausen. Non-contact procedures using laser and plasma appear reasonable to remove the DDT crystals. During the experiments, health and safety issues for the operator have to be taken into account. The removal of DDT was evaluated employing femtosecond and nanosecond laser radiation and cold atmospheric plasma techniques with different working gases (air, nitrogen, and argon). Before laser application, a chlorine measurement representing the DDT density on the wooden surface is done by X-ray fluorescence (XRF) analysis as reference. After laser processing, the XRF analysis is used again at the same surface position to determine the depletion rate. Additionally, a documentation and characterization of the sample surface is performed before and after laser and plasma treatment using optical microscopy (OM). For plasma processing with various systems a chlorine measurement is done by gas chromatographic-mass spectrometry (GCMS) analysis. T2 - 11th Conference on Lasers in the Conservation of Artworks CY - Kraków, Poland DA - 20.09.2016 KW - Decontamination KW - DDT KW - Wooden artworks KW - Femtosecond laser KW - Cold atmospheric pressure plasma PY - 2017 SN - 978-83-231-3875-4 DO - https://doi.org/10.12775/3875-4.17 SP - 241 EP - 251 PB - NCU Press CY - Toruń AN - OPUS4-43526 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Höhm, S. A1 - Epperlein, Nadja A1 - Spaltmann, Dirk A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Applications of laser-induced periodic surface structures (LIPSS) T2 - Proceedings of SPIE N2 - Laser-induced periodic surface structures (LIPSS, ripples) are a universal phenomenon that can be observed on almost any material after the irradiation by linearly polarized laser beams, particularly when using ultrashort laser pulses with durations in the picosecond to femtosecond range. During the past few years significantly increasing research activities have been reported in the field of LIPSS, since their generation in a single-step process provides a simple way of nanostructuring and surface functionalization towards the control of optical, mechanical or chemical properties. In this contribution current applications of LIPSS are reviewed, including the colorization of technical surfaces, the control of surface wetting, the tailoring of surface colonization by bacterial biofilms, and the improvement of the tribological performance of nanostructured metal surfaces. T2 - SPIE Photonics West Conference, Laser-based Micro- and Nanoprocessing XI CY - San Francisco, USA DA - 27.01.2017 KW - Laser-induced periodic surface structures (LIPSS) KW - Laser processing KW - Surface functionalization KW - Application PY - 2017 SN - 978-1-5106-0625-8 SN - 978-1-5106-0626-5 DO - https://doi.org/10.1117/12.2250919 SN - 0277-786X SN - 1996-756X VL - 10092 SP - Article UNSP 100920N, 100920N-1 EP - 100920N-9 PB - SPIE CY - Bellingham, USA AN - OPUS4-39305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hermens, U. A1 - Kirner, Sabrina A1 - Emonts, C. A1 - Comanns, P. A1 - Skoulas, E. A1 - Mimidis, A. A1 - Mescheder, H. A1 - Winands, K. A1 - Krüger, Jörg A1 - Stratakis, E. A1 - Bonse, Jörn T1 - Mimicking lizard-like surface structures upon ultrashort laser pulse irradiation of inorganic materials JF - Applied Surface Science N2 - Inorganic materials, such as steel, were functionalized by ultrashort laser pulse irradiation (fs- to ps-range) to modify the surface’s wetting behavior. The laser processing was performed by scanning the laser beam across the surface of initially polished flat sample material. A systematic experimental study of the laser processing parameters (peak fluence, scan velocity, line overlap) allowed the identification of different regimes associated with characteristic surface morphologies (laser-induced periodic surface structures, grooves, spikes, etc.). Analyses of the surface using optical as well as scanning electron microscopy revealed morphologies providing the optimum similarity to the natural skin of lizards. For mimicking skin structures of moisture-harvesting lizards towards an optimization of the surface wetting behavior, additionally a two-step laser processing strategy was established for realizing hierarchical microstructures. In this approach, micrometer-scaled capillaries (step 1) were superimposed by a laser-generated regular array of small dimples (step 2). Optical focus variation imaging measurements finally disclosed the three dimensional topography of the laser processed surfaces derived from lizard skin structures. The functionality of these surfaces was analyzed in view of wetting properties. KW - Femtosecond laser ablation KW - Laser-induced periodic surface structures KW - Lizard KW - Surface wetting KW - Fluid transport KW - Steel PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S0169433216328306 DO - https://doi.org/10.1016/j.apsusc.2016.12.112 SN - 0169-4332 SN - 1873-5584 VL - 418 IS - Part B SP - 499 EP - 507 PB - Elsevier, North-Holland CY - Amsterdam AN - OPUS4-40509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maresca, A. A1 - Krüger, O. A1 - Herzel, Hannes A1 - Adam, Christian A1 - Kalbe, Ute A1 - Astrup, T. F. T1 - Influence of wood ash pre-treatment on leaching behaviour, liming and fertilising potential JF - Waste Management N2 - In Denmark, increasing amounts of woody biomass are being used for the production of renewable energy, resulting in more wood ashes being generated. While these materials have been mainly landfilled, wood ashes may also be utilised for fertilizing and liming purposes on top of soils. Pre-treatments involving hardening or granulation may be carried out prior to soil application. In this study, two Danish wood ash samples were hardened and/or granulated. Lab-hardening induced rapid changes in the shape of the acid neutralisation capacity curve of the ashes. Up-flow column tests, assuming local equilibrium conditions, were employed to investigate the leaching from pre-treated ashes. Granules and loose ashes demonstrated similar leaching behaviours, indicating that similar geochemical processes were governing their leaching. In comparison with untreated fresh ashes, the hardened ashes demonstrated reduced leaching of Ca, Ba, Pb and Zn with concentration levels generally below or close to the analytical limits of quantification; to the contrary, the leaching of As, P, Sb, Si, V and Mg was enhanced in the hardened ashes. The release of alkalinity was reduced by hardening. In general, all granules were barely breakable by finger-pinching and they could withstand one month of continuous leaching, preserving their overall shape. The solubility of phosphorous in neutral ammonium citrate indicated that about 30–51% of the total P content in the ash samples was released, suggesting that the ashes could be potentially valuable as P-fertiliser if applied onto soil. KW - Wood ash KW - Phoshpor availability KW - Leaching KW - Forest soils PY - 2019 DO - https://doi.org/10.1016/j.wasman.2018.11.003 SN - 0956-053X VL - 83 SP - 113 EP - 122 PB - Elsevier AN - OPUS4-46583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kirner, Sabrina V. A1 - Hermens, U. A1 - Mimidis, A. A1 - Skoulas, E. A1 - Florian, C. A1 - Hischen, F. A1 - Plamadeala, C. A1 - Baumgartner, W. A1 - Winands, K. A1 - Mescheder, H. A1 - Krüger, Jörg A1 - Solis, J. A1 - Siegel, J. A1 - Stratakis, E. A1 - Bonse, Jörn T1 - Mimicking bug-like surface structures and their fluid transport produced by ultrashort laser pulse irradiation of steel JF - Applied Physics A N2 - Ultrashort laser pulses with durations in the fs-to-ps range were used for large area surface processing of steel aimed at mimicking the morphology and extraordinary wetting behaviour of bark bugs (Aradidae) found in nature. The processing was performed by scanning the laser beam over the surface of polished flat sample surfaces. A systematic variation of the laser processing parameters (peak fluence and effective number of pulses per spot diameter) allowed the identification of different regimes associated with characteristic surface morphologies (laser-induced periodic surface structures, i.e., LIPSS, grooves, spikes, etc.). Moreover, different laser processing strategies, varying laser wavelength, pulse duration, angle of incidence, irradiation atmosphere, and repetition rates, allowed to achieve a range of morphologies that resemble specific structures found on bark bugs. For identifying the ideal combination of parameters for mimicking bug-like structures, the surfaces were inspected by scanning electron microscopy. In particular, tilted micrometre-sized spikes are the best match for the structure found on bark bugs. Complementary to the morphology study, the wetting behaviour of the surface structures for water and oil was examined in terms of philic/ phobic nature and fluid transport. These results point out a route towards reproducing complex surface structures inspired by nature and their functional response in technologically relevant materials. KW - Biomometics KW - Surface wetting KW - Steel KW - Bug KW - Laser-induced periodic surface structures KW - Fluid transport KW - Femtosecond laser ablation PY - 2017 DO - https://doi.org/10.1007/s00339-017-1317-3 SN - 0947-8396 SN - 1432-0630 VL - 123 IS - 12 SP - 754, 1 EP - 13 AN - OPUS4-42817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Deubener, J. A1 - Allix, M. A1 - Davis, M.J. A1 - Duran, A. A1 - Höche, T. A1 - Honma, T. A1 - Komatsu, T. A1 - Krüger, S. A1 - Mitra, I. A1 - Müller, Ralf A1 - Nakane, S. A1 - Pascual, M.J. A1 - Schmelzer, J.W. A1 - Zanotto, E.D. A1 - Zhou, S. T1 - Updated definition of glass-ceramics JF - Journal of Non-Crystalline Solids N2 - Glass-ceramics are noted for their unusual combination of properties and manifold commercialized products for consumer and specialized markets. Evolution of novel glass and ceramic processing routes, a plethora of new compositions, and unique exotic nano- and microstructures over the past 60 years led us to review the Definition of glass-ceramics. Well-established and emerging processing methods, such as co-firing, additive manufacturing, and laser patterning are analyzed concerning the core requirements of processing glass-ceramics and the Performance of the final products. In this communication, we propose a revised, updated definition of glass-ceramics, which reads “Glass-ceramics are inorganic, non-metallic materials prepared by controlled crystallization of glasses via different processing methods. They contain at least one type of functional crystalline phase and a residual glass. The volume fraction crystallized may vary from ppm to almost 100%”. KW - Glass-ceramics definition PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-464711 DO - https://doi.org/10.1016/j.jnoncrysol.2018.01.033 SN - 0022-3093 SN - 1873-4812 VL - 501 SP - 3 EP - 10 PB - Elsevier B.V. AN - OPUS4-46471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brockmann, N. A1 - Sicken, A. A1 - Krüger, Jörg T1 - Effects of laser cleaning on the condition of different silk model samples using varying wavelengths and pulse durations JF - Heritage Science N2 - The cleaning of aged silk fibers poses a common challenge in the conservation of textiles, since traditional cleaning techniques often yield unsatisfactory results or even harm objects. In this regard, cleaning objects with laser radiation is a promising addition to the range of available methods. Due to it being contactless, even brittle and touch-sensitive objects with disfiguring or harmful soiling could potentially be cleaned and therefore made accessible for research and presentation. Examples of treatment have sometimes shown spectacular results. Still there is some skepticism concerning the safety of this treatment for textile materials, which has been strengthened through previous 532 nm wavelength nanosecond laser cleaning studies on silk fibers. Taking these published results into account, the range of examined laser parameters has been extended in this study, from 532 nm nanosecond laser to 1064 nm nanosecond and even 800 nm femtosecond laser, reevaluating the effect of this treatment on the fibers. The physicochemical processes taking place on the silk fibers when cleaning with lasers are complex and still not fully understood. The aim of this project was therefore to bring more clarification about potential effects of those processes on the condition of silk samples treated with a set of different parameters for wavelength, pulse duration, energy density and number of pulses per spot. It also looks at the influence of the presence of soiling on the results. The analysis of potential effects was then carried out using statistical methods and advanced analytics. Scanning electron microscopy, Fourier-transform infrared spectroscopy and colorimetry technology provided the required insights to better assess the effects. Results show that laser cleaning of silk fibers, like most other conventional cleaning techniques, is not completely without risk, but knowing what the possible effects are helps making decisions on whether the benefits of the technique used justify these risks. KW - Laser cleaning KW - Cultural heritage KW - Conservation KW - Silk PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594601 DO - https://doi.org/10.1186/s40494-024-01152-1 SN - 2050-7445 VL - 12 IS - 1 SP - 1 EP - 15 PB - Springer AN - OPUS4-59460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Tscheuschner, Georg A1 - Kaiser, Melanie N. A1 - Lisec, Jan A1 - Beslic, D. A1 - Muth, Thilo A1 - Krüger, M. A1 - Mages, H.-W. A1 - Dorner, B. G. A1 - Knospe, J. A1 - Schenk, J. A. A1 - Sellrie, F. A1 - Weller, Michael G. T1 - MALDI-TOF-MS-based identification of monoclonal murine anti-SARS-CoV-2 antibodies within one hour T2 - Preprints N2 - During the SARS-CoV-2 pandemic, many virus-binding monoclonal antibodies have been developed for clinical and diagnostic purposes. This underlines the importance of antibodies as universal bioanalytical reagents. However, little attention is given to the reproducibility crisis that scientific studies are still facing to date. In a recent study, not even half of all research antibodies mentioned in publications could be identified at all. This should spark more efforts in the search for practical solutions for the traceability of antibodies. For this purpose, we used thirty-five monoclonal antibodies against SARS-CoV-2 to demonstrate how sequence-independent antibody identification can be achieved by simple means applied onto the protein. First, we examined the intact and light chain masses of the antibodies relative to the reference material NIST-mAb 8671. Already half of the antibodies could be identified based solely on these two parameters. In addition, we developed two complementary peptide mass fingerprinting methods with MALDI-TOF-MS that can be performed in 45 minutes and had a combined sequence coverage of over 80%. One method is based on the partial acidic hydrolysis of the protein by 5 mM of sulfuric acid at 99 °C. Furthermore, we established a fast way for a tryptic digest without an alkylation step. We were able to show that the distinction of clones is possible simply by a brief visual comparison of the mass spectra. In this work, two clones originating from the same immunization gave the same fingerprints. Later, a hybridoma sequencing confirmed the sequence identity of these sister clones. In order to automate the spectral comparison for larger libraries of antibodies, we developed the online software ABID 2.0 (https://gets.shinyapps.io/ABID/). This open-source software determines the number of matching peptides in the fingerprint spectra. We propose that publications and other documents critically relying on monoclonal antibodies with unknown amino acid sequences should include at least one antibody fingerprint. By fingerprinting an antibody in question, its identity can be confirmed by comparison with a library spectrum at any time and context. KW - SARS-CoV-2 antibody KW - Reproducibility crisis KW - Peptide mass fingerprinting KW - Monoclonal antibody KW - Traceability KW - Antibody identification KW - Identity KW - Antibody light chain KW - MALDI-TOF-MS KW - Trypsin KW - Acidic cleavage KW - Antibody subclass KW - Database KW - Peak overlap KW - ABID KW - Sulfuric acid KW - Online software KW - Sequencing KW - Peptide coverage PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545182 DO - https://doi.org/10.20944/preprints202203.0229.v1 SN - 2310-287X SP - 1 EP - 24 PB - MDPI CY - Basel AN - OPUS4-54518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tscheuschner, Georg A1 - Kaiser, Melanie N. A1 - Lisec, Jan A1 - Beslic, D. A1 - Muth, Thilo A1 - Krüger, M. A1 - Mages, H. W. A1 - Dorner, B. G. A1 - Knospe, J. A1 - Schenk, J. A. A1 - Sellrie, F. A1 - Weller, Michael G. T1 - MALDI-TOF-MS-Based Identification of Monoclonal Murine Anti-SARS-CoV-2 Antibodies within One Hour JF - Antibodies N2 - During the SARS-CoV-2 pandemic, many virus-binding monoclonal antibodies have been developed for clinical and diagnostic purposes. This underlines the importance of antibodies as universal bioanalytical reagents. However, little attention is given to the reproducibility crisis that scientific studies are still facing to date. In a recent study, not even half of all research antibodies mentioned in publications could be identified at all. This should spark more efforts in the search for practical solutions for the traceability of antibodies. For this purpose, we used 35 monoclonal antibodies against SARS-CoV-2 to demonstrate how sequence-independent antibody identification can be achieved by simple means applied to the protein. First, we examined the intact and light chain masses of the antibodies relative to the reference material NIST-mAb 8671. Already half of the antibodies could be identified based solely on these two parameters. In addition, we developed two complementary peptide mass fingerprinting methods with MALDI-TOF-MS that can be performed in 60 min and had a combined sequence coverage of over 80%. One method is based on the partial acidic hydrolysis of the protein by 5 mM of sulfuric acid at 99 degrees C. Furthermore, we established a fast way for a tryptic digest without an alkylation step. We were able to show that the distinction of clones is possible simply by a brief visual comparison of the mass spectra. In this work, two clones originating from the same immunization gave the same fingerprints. Later, a hybridoma sequencing confirmed the sequence identity of these sister clones. In order to automate the spectral comparison for larger libraries of antibodies, we developed the online software ABID 2.0. This open-source software determines the number of matching peptides in the fingerprint spectra. We propose that publications and other documents critically relying on monoclonal antibodies with unknown amino acid sequences should include at least one antibody fingerprint. By fingerprinting an antibody in question, its identity can be confirmed by comparison with a library spectrum at any time and context. KW - Reproducibility KW - Quality control KW - Traceability KW - Peptides KW - Peptide mass fingerprinting KW - Monoclonal antibody KW - Recombinant antibody KW - Identity KW - Antibody identification KW - Sequencing KW - Light chain KW - Mass spectrometry KW - Software KW - Open science KW - Library KW - COVID-19 KW - Corona virus KW - Sequence coverage KW - NIST-mAb 8671 KW - Reference material KW - RBD KW - Spike protein KW - Nucleocapsid KW - Cleavage KW - Tryptic digest KW - MALDI KW - DHAP KW - 2,5-dihydroxyacetophenone KW - Github KW - Zenodo KW - ABID PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547347 DO - https://doi.org/10.3390/antib11020027 VL - 11 IS - 2 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-54734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Czichocki, G. A1 - Heger, R. A1 - Much, Helmut A1 - Krüger, Ralph-Peter A1 - Goedel, W.A. T1 - Synthesis of Polyisoprenes with Sulfonate Head Groups and their Purification by HPLC JF - Tenside, surfactants, detergents PY - 2001 SN - 0932-3414 SN - 0040-3490 VL - 38 IS - 3 SP - 168 EP - 172 PB - Hanser CY - München AN - OPUS4-2175 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tressl, R. A1 - Wondrak, G. T. A1 - Garbe, L.-A. A1 - Krüger, Ralph-Peter A1 - Rewicki, D. T1 - Pentoses and Hexoses as Sources of New Melanoidin-like Maillard-Polymers JF - Journal of agricultural and food chemistry KW - Model compounds for melanoidins KW - Pyrroles from pentoses and hexoses KW - Beta-dicarbonyl pathway of the Maillard reaction KW - Polycondensation KW - MALDI-TOF-MS analysis KW - Antioxidative activity of oligomeric model compounds PY - 1998 SN - 0021-8561 SN - 1520-5118 VL - 46 IS - 5 SP - 1765 EP - 1776 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-2159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Birgit Angelika A1 - Ziemann, M. A A1 - Pentzien, Simone A1 - Gabsch, T. A1 - Koch, W. A1 - Krüger, Jörg T1 - Technical analysis of a Central Asian wall painting detached from a Buddhist cave temple on the northern Silk Road JF - Studies in Conservation N2 - A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified. KW - Wall paintings KW - Central Asia KW - Silk Road KW - Pigments KW - Microscopy PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-357297 DO - https://doi.org/10.1179/2047058414Y.0000000152 VL - 61 IS - 2 SP - 113 EP - 122 PB - Routledge Taylor & Francis Group CY - London AN - OPUS4-35729 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Watolla, Marie-Bernadette A1 - Gluth, Gregor A1 - Sturm, Patrick A1 - Rickard, W.D.A. A1 - Krüger, Simone A1 - Schartel, Bernhard T1 - Intumescent geopolymer-bound coatings for fire protection of steel JF - Journal of ceramic science and technology N2 - The passive fire protection of steel structures and other load-bearing components will continue to gain importance in future years. In the present contribution, novel intumescent aluminosilicate (geopolymer-bound) composites are proposed as fire-protective coatings on steel. Steel plates coated with these materials were exposed to the standard temperature-time curve as defined in ISO 834 – 1:1999. The coatings partially foamed during curing and expanded further during thermal exposure, demonstrating their intumescent characteristic.Thermogravimetryandoscillatory rheometry determined that the intumescent behavior is attributed to a transition to a viscous state (loss factor > 1) in the temperature range of major water release, differing from conventional geopolymers. XRD and SEM images showed that the coatings had characteristics of ceramic or glass-ceramic foams after fire resistance testing, suggesting superior performance under challenging conditions. The thickness of the coatings influenced their foaming and intumescent behavior and thus the time for the coated steel plates to reach 500 °C. A number of additives were also studied with the best performance obtained from samples containing sodium tetraborate.Acoating of just 6mmwas able to delay the time it takes for a steel substrate to reach 500 °C to more than 30 minutes. KW - Geopolymers KW - Fire protection KW - Intumescence KW - Coatings KW - Fire resistance PY - 2017 UR - https://www.ceramic-science.com/articles/all-articles.html?article_id=100558 DO - https://doi.org/10.4416/JCST2017-00035 VL - 8 IS - 3 (Topical issue: Geopolymers) SP - 351 EP - 364 PB - Göller Verlag CY - Baden-Baden AN - OPUS4-42139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -