TY - CONF A1 - Sturm, Heinz T1 - Rasterkraftmikroskopie mit Leitfähigkeitskontrast T2 - Tagung "Raster-Sonden-Methoden und Organische Materialien" am Europäischen Lab. für Molekularbiologie CY - Heidelberg, Germany DA - 1994-10-11 PY - 1994 AN - OPUS4-6372 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Rastersondenverfahren: Materialkontraste und Nanolithographie T2 - DGM Fachausschuss "Gefüge und Eigenschaften von Polymerwerkstoffen" CY - Berlin, Germany DA - 2003-12-05 PY - 2003 AN - OPUS4-2917 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - An AFM-ESEM hybrid instrument T2 - BAM Symposium "Polymere Verbundwerkstoffe zwischen Raumtemperatur und 4,2K" CY - Berlin, Germany DA - 2003-02-27 PY - 2003 AN - OPUS4-4095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Methods for simultaneous measurements of topography and local electrical properties using scanning force microscopy T2 - 9th International Symposium on Electrets (ISE9) CY - Shanghai, China DA - 1996-09-15 PY - 1996 AN - OPUS4-6396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Robust plasmonic substrates T2 - E-MRS 2013 Spring Meeting CY - Strasbourg, France DA - 2013-05-21 PY - 2013 AN - OPUS4-28487 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - From microstructures to nanodots: AFM experiments with a piezoelectric polymer T2 - iThemba LABS CY - Somerset West, South Africa DA - 2002-02-03 PY - 2002 AN - OPUS4-6527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Studies of wear on materials by SPM T2 - Workshop em Microscopiy de Forca Atomica e tecnicas correlatas CY - Rio de Janeiro, Brazil DA - 1997-10-14 PY - 1997 AN - OPUS4-6423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - SFM of Polymers with Harmonically Modulated Friction Force T2 - 24th Intern. TopoMetrix-Workshop: Aktuelle Entwicklungen in der Nanotechnologie und der Rastersondenmikroskopie, Humboldt-Universität CY - Berlin, Germany DA - 1998-03-12 PY - 1998 AN - OPUS4-6459 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Prinzipien der Rastersondenmikroskopie T2 - Vortrag am Institut für Nichtmetallische Werkstoffe der TU Berlin CY - Berlin, Germany DA - 2005-11-03 PY - 2005 AN - OPUS4-11315 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marwitz, Christian A1 - Stegemann, B. A1 - Breitkreiz, Maxim A1 - Spaltmann, Dirk A1 - Kloß, Heinz A1 - Woydt, Mathias A1 - Sturm, Heinz T1 - Correlation of adhesion force and electrical conductivity in Magnéli-type vanadium oxides and highly oriented pyrolytic graphite N2 - A correlation of adhesion force and electrical conductivity is established for a vanadium oxide and highly oriented pyrolytic graphite (HOPG). Adhesion forces were determined by analysis of pull-off forces obtained from force–distance curves with atomic force microscopy in ultrahigh vacuum, on clean surfaces and with defined contact conditions. The investigated samples include (i) different stoichiometries of Magnéli-type vanadium oxides (V3O5, V4O7, V6O11, and V7O13), which undergo metal-insulator-transitions as a function of temperature, (ii) the (0001) basal plane and the (10–10) prism plane of highly oriented pyrolytic graphite (HOPG), which differ in their respective perpendicular-plane electrical conductivities by several orders of magnitude, and (iii) the (100) surfaces of pure metal single crystals, i.e., silver (Ag), copper (Cu), iron (Fe) and gold (Au). It is shown, that the vanadium oxides as well as the graphite exhibit significantly lower adhesion forces in their electrical conductive state than in their non-electrical conductive state. The values obtained for the electrical conductive states are quantitatively confirmed by the measurements on the single crystal metals. KW - Adhesion force KW - HOPG KW - Vanadium oxide KW - Magnéli phases KW - Single crystal metals KW - Atomic force microscopy PY - 2011 DO - https://doi.org/10.1016/j.susc.2011.04.014 SN - 0039-6028 VL - 605 IS - 13-14 SP - 1271 EP - 1274 PB - Elsevier CY - Amsterdam AN - OPUS4-23953 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munz, Martin A1 - Sturm, Heinz A1 - Stark, Wolfgang T1 - Mechanical gradient interphase by interdiffusion and antiplasticisation effect - study of an epoxy/thermoplastic system N2 - A stoichiometric amine–epoxy formulation was cured in the presence of a thermoplastic, namely poly(vinylpyrrolidone) (PVP). The epoxy system consisted of the resin diglycidyl ether of bisphenol A (DGEBA) and the aromatic curing agent 4,4'-diaminodiphenylsulfone (DDS). As shown for this system in a former study by Oyama et al. [Oyama HT, Lesko JJ, Wightman JP. J Polym Sci B 1997;35:331–46. [36]], preferential absorption of amine molecules by PVP can occur. In the present study, the focus is on the variations of local elastic properties within the epoxy interphase adjacent to the PVP layer. The curing was performed close to the glass transition temperature, Tα, of the PVP film, namely at 170 °C. Variations of the local amine concentration were tracked using energy-dispersive analysis of X-rays (EDX), by taking benefit of the sulfur contained in DDS. Using temperature-dependent dynamic mechanical analysis (DMA), a series of epoxy reference samples of different amine–epoxy concentration ratios, r, was investigated in order to work out the relationship between r and the epoxy storage modulus at room temperature. In the excess-epoxy regime, r<1, the modulus is observed to increase with departure from the stoichiometric ratio, r=1. Considering the respective suppression of the ß-transition, the observed characteristic can be explained by an antiplasticisation effect. Depth-sensing indentation (DSI) experiments across the epoxy/PVP interphase provided evidence for strong modulus variations. In consistency with the EDX and the DMA data, in the vicinity of the PVP layer the local epoxy modulus is increased. The total change of the epoxy Young's modulus is ~1.1 GPa. However, the total width of the modulus decay of ~175 µm is ~2.5 times larger than the one of the DDS concentration gradient. This finding is discussed in terms of additional spatial variations of the DGEBA concentration as well as long-range diffusion currents of DDS induced by the interdiffusion processes and their effect on the final network of crosslinks. KW - Interdiffusion KW - Interphase/interface KW - Polymer PY - 2005 DO - https://doi.org/10.1016/j.polymer.2005.06.098 SN - 0032-3861 SN - 1873-2291 VL - 46 IS - 21 SP - 9097 EP - 9112 PB - Springer CY - Berlin AN - OPUS4-10893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Experimente mit Polymeren: Statische und dynamische Indentation, Reibung, Referenzproben der BAM T2 - Milestone-Meeting BMBF-Projekt "Entwicklung und Optimierung von Prüfmethoden zur quantitativen Bestimmung elestischer Eigenschaften in nanoskaligen Dimensionen mit Rastersondenmikroskopie" in der BASF CY - Ludwigshafen am Rhein, Germany DA - 2003-12-11 PY - 2003 AN - OPUS4-4096 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Rasterkraftmikroskopie mit Leitfähigkeitskontrast zur Oberflächenanalyse von Carbonfaser-Compositen T2 - Tagung "Funktionalisierte dünne organische Schichten und Grenzflächen" CY - Potsdam, Germany DA - 1995-05-22 PY - 1995 AN - OPUS4-6384 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Waegner, M. A1 - Schröder, M. A1 - Suchaneck, G. A1 - Sturm, Heinz A1 - Weimann, Christiane A1 - Eng, L. M. A1 - Gerlach, G. T1 - Enhanced piezoelectric response in nano-patterned lead zirconate titanate thin films N2 - In this work, Pb(Zr,Ti)O3 thin films were used to fabricate well-ordered nanodot arrays by means of nanosphere lithography. This technique is based on a two-step etch process that enables excellent control of the fabrication of ordered nanodisc arrays of defined height, diameter, and pitch. Piezoresponse force microscopy was used to investigate both non-patterned and patterned films. The topography and both the out-of-plane and the in-plane polarization were deduced in this mode. Grains of nanodots with a low aspect ratio form domain structures comparable to domains in non-patterned two-dimensional films. In contrast, nanodots with a higher aspect ratio form particular structures like bi-sectioned domain assemblies, c-shaped domains or multi-domains surrounding a center domain. The patterning of the ferroelectric material was shown to affect the formation of ferroelectric domains. The initial polycrystalline films with random polarization orientation re-orient upon patterning and then show domain structures dependent on the nanodisc diameter and aspect ratio. KW - Nanostructures KW - Ferroelectric KW - Nanodots PY - 2012 DO - https://doi.org/10.1143/JJAP.51.11PG04 SN - 0021-4922 VL - 51 SP - 1 EP - 5 PB - IOP Publ. CY - Bristol AN - OPUS4-27697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Methods for Simultaneous Measurements of Topography and Local Electrical Properties: Conductivity, Capacity, Surface Charge and Inverse Piezoelectricity T2 - Workshop: Rastersondenmikroskopie in Forschung und Industrie an der GH Wuppertal CY - Wuppertal, Germany DA - 1999-03-11 PY - 1999 AN - OPUS4-6496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Untersuchung heterogener Werkstoffe mittels dynamisch-mechanischer Zusatz-Kontraste im AFM T2 - 17. SPM Workshop: Fhl. Keramische Technologien und Sinterwerkstoffe CY - Dresden, Germany DA - 1997-03-13 PY - 1997 AN - OPUS4-6413 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heyde, M. A1 - Sturm, Heinz A1 - Geuss, Markus A1 - Ritter, C. A1 - Rademann, K. T1 - Rastersondenmikroskopie als Werkzeug der Lithographie für Nanostrukturen PY - 1999 SN - 0946-641X VL - 6 IS - 3 SP - 28 EP - 33 PB - Universität CY - Berlin AN - OPUS4-6861 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Sturm, Heinz ED - Czichos, Horst ED - Habig, K.-H. T1 - Messtechnik der Mikro- und Nanoskala PY - 2010 SN - 978-3-8348-1810-2 SP - 1 EP - 18 PB - Springer-Vieweg CY - Wiesbaden AN - OPUS4-21576 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Studies of polymers by SPM T2 - Workshop em Microscopia de Forca Atomica e tecnicas correlatas CY - Rio de Janeiro, Brazil DA - 1997-10-14 PY - 1997 AN - OPUS4-6422 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Baudach, Steffen A1 - Kautek, Wolfgang A1 - Geuss, Markus A1 - Sturm, Heinz T1 - The precision of the femtosecond-pulse laser ablation of TiN films on silicon N2 - Ti:sapphire laser pulses of 130 fs and 800 nm were focused on 3.2-7m-thick TiN films by a 60-mm focal length lens in air. The morphology of the ablated areas generated by laser pulses at a fluence slightly above the ablation threshold was characterized in dependence on the pulse number by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The cavity profiles, depths, diameters, and volumes were quantitatively evaluated by AFM. The polarization state of the laser light is discussed as a further parameter, in addition to fluence and pulse number, that influences and controls the ablation precision of these materials. It was observed that circularly polarized radiation enhances the average ablation rates and reduces the roughness in the cavities by a factor of 2-3 as compared to linearly polarized radiation of the same incident laser fluence. Special attention was paid to the interfacial region between the coating and substrate. Ultrashort-pulse laser drilling into the Si substrate revealed the generation of columnar features which even may surmount the original coating under laser conditions. T2 - 5th International Conference on Laser Ablation ; COLA '99 CY - Göttingen, Germany DA - 1999-07-19 KW - Laser ablation KW - Picosecond PY - 1999 DO - https://doi.org/10.1007/s003390051425 SN - 0947-8396 VL - 69 IS - 7 SP - S399 EP - S402 PB - Springer CY - Berlin AN - OPUS4-778 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hartmann, S A1 - Sturm, Heinz A1 - Blaudeck, T A1 - Hoelck, O A1 - Hermann, S A1 - Schulz, SE A1 - Wunderle, B. T1 - Experimental and computational studies on the role of surface functional groups in the mechanical behavior of interfaces between single-walled carbon nanotubes and metals N2 - To study the mechanical interface behavior of single-walled carbon nanotubes (CNTs) embedded in a noble metal, we performed CNT-metal pull-out tests with in situ scanning electron microscope experiments. Molecular dynamics (MD) simulations were conducted to predict force-displacement data during pull-out, providing critical forces for failure of the system. In MD simulations, we focused on the influence of carboxylic surface functional groups (SFGs) covalently linked to the CNT. Experimentally obtained maximum forces between 10 and 102 nN in palladium and gold matrices and simulated achievable pulling forces agree very well. The dominant failure mode in the experiment is CNT rupture, although several pull-out failures were also observed. We explain the huge scatter of experimental values with varying embedding length and SFG surface density. From simulation, we found that SFGs act as small anchors in the metal matrix and significantly enhance the maximum forces. This interface reinforcement can lead to tensile stresses sufficiently high to initiate CNT rupture. To qualify the existence of carboxylic SFGs on our CNT material, we performed analytical investigation by means of fluorescence labeling of surface species and discuss the results. With this contribution, we focus on a synergy between computational and experimental approaches involving MD simulations, nano scale testing, and analytics (1) to predict to a good degree of accuracy maximum pull-out forces of single-walled CNTs embedded in a noble metal matrix and (2) to provide valuable input to understand the underlying mechanisms of failure with focus on SFGs. This is of fundamental interest for the design of future mechanical sensors incorporating piezoresistive single-walled CNTs as the sensing element. KW - Oxygen-containing functionalities KW - Molecular-dynamics KW - Structural characterization KW - Reinforced composites KW - Raman spectroscopy KW - Shear strength KW - Polymer matrix KW - Pull-out KW - Simulation KW - Purification PY - 2016 DO - https://doi.org/10.1007/s10853-015-9142-6 SN - 0022-2461 SN - 1573-4803 VL - 51 IS - 3 SP - 1217 EP - 1233 AN - OPUS4-35795 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sturm, Heinz A1 - Schulz, Eckhard T1 - Local AC current contrast on carbon fiber surfaces imaged by scanning force microscopy N2 - After a delamination process in a C-fiber reinforced polymer composite, the identification of the polymer residue of poly-(phenylene sulphide) on carbon fiber surfaces gives important information on the composite failure mechanism. Using scanning force microscopy (SFM) in its lateral force imaging mode or with the stiffness imaging mode, it is almost impossible to distinguish the two composite components owing to a very low material-based contrast of the local friction and compliance. The new technique using contrast based on a local AC current measurement allows a clear identification of the conducting carbon fiber and the non-conducting polymer coverage. KW - Matrix adhesion KW - Films KW - Photoconduction KW - Composites PY - 1995 DO - https://doi.org/10.1002/actp.1995.010460505 SN - 0323-7648 SN - 1521-4044 VL - 46 IS - 5 SP - 379 EP - 384 PB - Wiley-VCH Verl. CY - Weinheim, Germany AN - OPUS4-6848 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munz, Martin A1 - Schulz, Eckhard A1 - Sturm, Heinz T1 - Reliability of polymer materials - the nanoscopic view on interphases T2 - Kick-off Meeting zu einem gemeinsamen DAAD-Projekt mit der Universidad Pais Vasco (UVP), Dept. of Chemical and Environmental Engineering, Industrial Engineering School (EITI), Materials and Technologies Group CY - San Sebastián, Spain DA - 2002-08-08 PY - 2002 SP - 1(?) EP - 12(?) AN - OPUS4-1832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - SFM-Nanomechanics - Constant Dynamic Indentation- and Harmonically Modulated Friction Force- Microscopy T2 - Workshop: Rastersondenmikroskopie in Forschung und Industrie an der GH Wuppertal CY - Wuppertal, Germany DA - 1999-03-11 PY - 1999 AN - OPUS4-6495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Physical properties of nanometer sized particles characterised by Scanning Probe Microscopy Techniques T2 - 2nd German Brazilian Workshop on Applied Surface Science CY - Templin, Germany DA - 1998-09-21 PY - 1998 AN - OPUS4-6454 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heyde, M. A1 - Sturm, Heinz T1 - A new application of scanning probe microscopy piezos T2 - Raster-Sonden-Mikroskopien und organische Materialien VII CY - Berlin, Germany DA - 1998-10-07 PY - 1998 AN - OPUS4-6466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barthel, Anne-Kathrin A1 - Wachtendorf, Volker A1 - Sturm, Heinz A1 - Meyer-Plath, Asmus ED - Reichert, T. T1 - Irradiation-induced surface changes on CNT-filled polymeric materials N2 - The present study examines weathering-related degradation mechanisms of CNT-containing polymers and discusses whether and under what conditions degradation might lead to the release of nanoscale components. For this purpose, the study used accelerated artificial aging. The photodegradation of composites based polycarbonate containing multi-walled CNTs of type "Baytubes C150P" was studied under irradiation with a Xenon-arc irradiation device (λ-cut-off at 290 nm). Resulting surface modifications were evaluated with complementary chemical and microscopic characterization techniques. At sufficiently high radiation dose, a significant degradation of the matrix was observed for some of the polymers under examination which led to entangled networks of uncovered CNT at the composite surface. By investigation of potential exposure mechanisms of CNTs in polymer composites, the present work contributes to the risk assessment of CNT-containing products. T2 - 6th European weathering symposium Natural and artificial ageing of polymers CY - Bratislava, Slovak Republic DA - 11.09.2013 PY - 2013 SN - 978-3-9813136-8-0 N1 - Serientitel: CEEES Publication – Series title: CEEES Publication IS - 16 SP - 295 EP - 308 AN - OPUS4-31161 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solomun, Tihomir A1 - Sturm, Heinz A1 - Wellhausen, R. A1 - Seitz, H. T1 - Interaction of a single-stranded DNA-binding protein g5p with DNA oligonucleotides immobilised on a gold surface N2 - We report surface plasmon resonance (spr) and confocal fluorescence results concerning the interaction of a gene-5-protein (g5p) with single-stranded DNA oligonucleotides (dT25) tethered to a gold surface. The spr data show that a highly stable g5p–ssDNA complex is readily formed on a gold surface with koff = 1.7 × 10-3 s-1. The extent of the complexion indicated involvement of the cooperative protein–protein interactions within the binding to DNA. In the experiments where dT25 coexist with g5p in the solution, the fluorescence data show that g5p also mediates the binding between the non-complementary oligonucleotides in the solution and those immobilised on the surface. KW - Single stranded DNA KW - g5p protein PY - 2012 DO - https://doi.org/10.1016/j.cplett.2012.03.017 SN - 0009-2614 SN - 1873-4448 VL - 533 SP - 92 EP - 94 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-26525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solomun, Tihomir A1 - Schimanski, A. A1 - Sturm, Heinz A1 - Mix, Renate A1 - Illenberger, E. T1 - Surface Modification of Polyamides by Direct Fluorination N2 - Bulk samples and thin films of polyamides (PA6 and PA12) were exposed to fluorine (1 - 10 vol.-% F2 in N2) and analysed with photoelectron (XPS) and infrared spectroscopy. Fluorination affects both, the amide and the hydrocarbon parts of the polymers. However, only the carbon atom next to the carbonyl is readily fluorinated. Chemical modification of the amide group is apparent in a large binding energy shift (+5 eV) of the N1s level and the appearance of a CO band at 1734 cm-1. It is concluded that the amide C-N bond is cleaved in the fluorination process and that COOH and NF2 end groups are formed. This conclusion is corroborated by the appearance of ester oxygen in the XPS and by the 19F NMR spectra of the volatile products that show fluorine signals chemically shifted about 200 ppm towards lower field as compared with the CHF environment. KW - Gasfluorierung KW - IR KW - XPS KW - AFM KW - NF2-Gruppe PY - 2004 UR - http://www.e-polymers.org SN - 1618-7229 IS - 8 SP - 1 EP - 16 PB - De Gruyter CY - [S.l.] AN - OPUS4-3425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Fertigung und Charakterisierung von Kalibrierproben T2 - 1. Treffen im Verbundprojekt Entwicklung und Optimierung von Prüfmethoden zur quantitativen Bestimmung elastischer Eigenschaften in nanoskaligen Dimensionen mit Rastersondenmikroskopie, IZPF CY - Saarbrücken, Germany DA - 2002-09-04 PY - 2002 AN - OPUS4-6526 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Scanning Force Microscopy (SFM) with additional mechanical and electrical materials contrasts T2 - Seminar of the Department of Materials and Interfaces, Weizmann Institute of Science CY - Rehovot, Israel DA - 1997-02-16 PY - 1997 AN - OPUS4-6412 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solomun, Tihomir A1 - Mix, Renate A1 - Sturm, Heinz T1 - Immobilization of silanized DNA on glass: influence of the silane tether on the DNA hybridization N2 - Two trifunctional (trimethoxy and triethoxy) and one difunctional (methyldimethoxy) 3-mercaptopropyl-alkoxysilanes were covalently tethered to thiolated DNA oligonucleotides in solution. After deposition as microarrays onto glass, the immobilized DNA probes were tested for hybridization ability by a florescence-based method. The results demonstrate a large enhancement in the fluorescence signal when the functionality of the silane tether is reduced from three to two. An XPS analyses revealed that this is not due to a higher DNA surface density. FTIR spectra of the spin-coated silanes showed that the trifunctional silanes form branched and cyclic siloxane moieties, whereas the difunctional silane generates predominantly short straight siloxane chains. Therefore, the propensity of trifunctional silanes to form more complex networks leads to conformations of the bound DNA which are less favorable for the specific interaction with the complementary strand. The data implicate that further significant improvements in the DNA hybridization ability are possible by adroit choice of the silane system. KW - Silanized DNA KW - DNA immobilization KW - DNA hybridization KW - Fluorescence imaging KW - FTIRS KW - XPS PY - 2010 DO - https://doi.org/10.1021/am100263t SN - 1944-8244 SN - 0013-936X SN - 1944-8252 VL - 2 IS - 8 SP - 2171 EP - 2174 PB - ACS Publ. CY - Washington, DC, USA AN - OPUS4-22614 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Trappe, Volker A1 - Hickmann, Stefan A1 - Sturm, Heinz T1 - Bestimmung des Zwischenfaserbruchversagens in textilverstärktem Glasfaserkunststoff mittels der Röntgenrefrationstopografie N2 - Moderne Leichtbaustrukturen (Luftfahrt, Eisenbahn, Automotive) aus Faserverbundwerkstoffen (FVW) sind hohen mechanischen und klimatischen Beanspruchungen ausgesetzt. Aussagen über die Lebensdauer und Funktionssicherheit der FVW-Bauteile können eher aus Untersuchungen der mikromechanischen Eigenschaften gewonnen werden als aus der globalen Festigkeit. Die Röntgenrefraktionstopografie ist ein Verfahren zur zerstörungsfreien Bestimmung von inneren Oberflächen in Werkstoffen. Angewendet auf FVW lassen sich Aussagen über die Faserorientierungen, die Fertigungsqualität sowie über Faser-Matrix-Ablösungen und Matrixrisse infolge mechanischer Beanspruchung gewinnen. Nachfolgend wird ein neues Verfahren zur Bestimmung des Zwischenfaserbruchversagens am komplexen Laminat vorgestellt. Hierbei wird das Röntgenrefraktionsverfahren "online“ bei Zug-Belastung der Probe angewendet. KW - Zerstörungsfreie Prüfung KW - Röntgenstreuung KW - Faserverbundwerkstoffe KW - Mikrorissbildung KW - Glasfaserverstärkter Kunststoff PY - 2008 SN - 0025-5300 VL - 50 IS - 10 SP - 615 EP - 622 PB - Hanser CY - München AN - OPUS4-18282 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Messungen lokaler elektrischer Eigenschaften an keramischen Dielektrika T2 - 29. Kolloquium des Arbeitskreises für Elektronenmikroskopische Direktabbildung und Analyse von Oberflächen (EDO) der Deutschen Gesellschaft für Elektronenmikroskopie e.V. CY - Münster, Germany DA - 1996-10-10 PY - 1996 AN - OPUS4-6393 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Reducing bleaching in organic nanofibers by bi-layer polymer/oxide coating T2 - 10. International Conference on "Nanostructured Material" (NANO 2010) CY - Rome, Italy DA - 2010-09-13 PY - 2010 AN - OPUS4-21952 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Messungen der lokalen Leitfähigkeit und Oberflächenaufladung im Rasterkraftmikroskop T2 - Frühjahrstagung des Fachausschusses Polymerphysik der Deutschen Physikalischen Gesellschaft (DPG) CY - Marburg, Germany DA - 1996-03-18 PY - 1996 AN - OPUS4-6395 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Rasterkraftmikroskopie in der Faserverbundwerkstoffforschung T2 - Berliner Polymerentage CY - Berlin, Germany DA - 1993-05-06 PY - 1993 AN - OPUS4-6382 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munz, Martin A1 - Sturm, Heinz A1 - Schulz, Eckhard T1 - Interphase Characterization via the Stiffness Contrast of a Scanning Force Microscope in Displacement Modulation Mode N2 - The physical properties as well as the thickness of the interphase between polymer and reinforcing phase are generally expected to show a strong influence on the macroscopic mechanical properties of composite materials. In this study the scanning force microscope (SFM) has been applied for detecting stiffness gradients near the interface between copper and epoxide. In displacement modulation mode the load exerted by the tip is modulated sinusoidally by vibrating the normal position of the cantilever or the sample. The corresponding amplitude of dynamic cantilever bending is related to local surface stiffness. Thus, using the SFM, the local mechanical properties of the surface under investigation can be probed. When scanning the tip across the reinforcement/polymer interface, the polymeric interphasial zone can be identified with the observed stiffness gradient. For a commercial epoxide based on diglycidyl ether of bisphenol A (DGEBA) cured with an amine-containing hardener, a stiffness gradient was detected that could be fitted by a Gaussian profile typical for diffusional processes. The width of the stiffness gradient was 280 nm. The observation is discussed in terms of interface-induced segregation processes between resin and hardener, as well as heat conduction mechanisms that can occur during the exothermic curing reaction. Both mechanisms are diffusional in nature and, via the local network structure, are expected to show some influence on the local stiffness of the cured epoxy. Copyright © 2000 John Wiley & Sons, Ltd. T2 - ECASIA 99 CY - Sevilla, Spain DA - 1999-10-04 KW - Scanning Force Microscopy KW - Surface properties KW - Nanomechanics KW - Interface/Interphase KW - Polymer-matrix composites (PMCs) KW - Adherends PY - 2000 DO - https://doi.org/10.1002/1096-9918(200008)30:1<410::AID-SIA846>3.0.CO;2-G SN - 0142-2421 SN - 1096-9918 VL - 30 IS - 1 SP - 410 EP - 414 PB - Wiley CY - Chichester AN - OPUS4-873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Braun, Ulrike A1 - Sturm, Heinz A1 - Schartel, Bernhard T1 - Flame retardancy mechanisms of aluminium phosphinate in glass-fibre reinforced polyester T2 - Flame Retardants 2008 Conference CY - London, UK DA - 2008-02-12 PY - 2008 SN - 978-0-9556548-1-7 SP - 133 EP - 140 PB - Interscience Communications CY - London, UK AN - OPUS4-17785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Modulated Lateral Force Microscopy (M-LFM): principles, experiments and unsolved problems T2 - Institut für Physik der Universität Basel CY - Basel, Switzerland DA - 2003-02-20 PY - 2003 AN - OPUS4-4097 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Kraft-Modulationstechniken am AFM zum Schreiben und Analysieren kleiner Strukturen T2 - BAM-Kolloquium CY - Berlin, Germany DA - 2000-11-09 PY - 2000 AN - OPUS4-6506 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barthel, Anne-Kathrin A1 - Wachtendorf, Volker A1 - Sturm, Heinz A1 - Meyer-Plath, A. ED - Ziegahn, K.-F. T1 - Wirkung simulierter Sonnenstrahlung auf Kohlenstoffnanoröhren gefüllte Polymerkomposite N2 - Durch das Füllen von Polymeren mit Nanopartikeln oder Nanoröhren werden verbesserte Materialeigenschaften z.B. bezüglich mechanischer Stabilität, Witterungsbeständigkeit, elektrischer Leitfähigkeit und Flammschutz angestrebt. Mit dem vermehrten Einsatz derartiger Nanokomposite gewinnen aber auch Fragen des Umwelt- und Gesundheitsschutzes an Bedeutung. Es gilt zu klären, ob durch Herstellung, Benutzung und Witterungsbeanspruchung möglichweise nanoskalige Partikel freigesetzt werden können. Zu diesem Zweck wurden mit Kohlenstoffnanoröhren, Carbon Nanotubes (CNT), gefüllte Polymerkomposite spektral breitbandig wie auch quasimonochromatisch unter variierter klimatischer Beanspruchung bestrahlt. Die sich vor allem an der Oberfläche mit der Alterung abzeichnenden Veränderungen wurden mikroskopisch und spektroskopisch charakterisiert. T2 - 43. Jahrestagung der GUS 2014 CY - Stutensee-Blankenloch, Germany DA - 26.03.2014 KW - Nanokomposit KW - Nanopartikel KW - CNT KW - Bewitterung KW - Bestrahlung KW - Simulierte Sonnenstrahlung KW - Alterung PY - 2014 SN - 978-3-9816286-0-9 SP - 65 EP - 74 AN - OPUS4-31160 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bovtun, V. A1 - Sturm, Heinz A1 - Pashkov, V.M. ED - Baptista, J. T1 - Investigation of local electrical properties and topography of homo- and heterogeneous TiO2-containing ceramics by scanning force microscopy (SFM) T2 - 5th International Conference on Electronic Ceramics & Applications CY - Aveiro, Portugal DA - 1996-09-02 KW - Ceramics KW - Scanning force microscopy KW - SFM KW - Electrical properties KW - Heterogeneity PY - 1996 SN - 972-828317-2 VL - 2 SP - 117 EP - 120 PB - Fundação João Jacinto de Magalhães CY - Aveiro AN - OPUS4-6850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Methoden der Rasterelektronen- und Rasterkraftmikroskopie zur Analyse von Faserverbundwerkstoffen T2 - 15. Nationales Symposium SAMPE Deutschland e.V. CY - Berlin, Germany DA - 2009-02-18 PY - 2009 AN - OPUS4-20750 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Nanotechnologie auf Kunststoff-Oberflächen T2 - Hannover-Messe CY - Hanover, Germany DA - 1999-04-19 PY - 1999 AN - OPUS4-6499 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Characterisierung des Faser/Polymer-Interface mittels messungen lokaler mikromechanischer Eigenschaften in der Rasterkraftmikroskopie T2 - Frühjahrstagung der DPG, FA: Polymerphysik CY - Münster, Germany DA - 1997-03-17 PY - 1997 AN - OPUS4-6414 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Messung elektrischer Eigenschaften in der Rasterkraftmikroskopie: Leitfähigkeitskontrast und Ladungskontrast T2 - 1. Jenaer Anwendersymposium Rastersondenmikroskopie CY - Jena, Germany DA - 1995-11-22 PY - 1995 AN - OPUS4-6390 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munz, Martin A1 - Schulz, Eckhard A1 - Sturm, Heinz T1 - Use of scanning force microscopy studies with combined friction, stiffness and thermal diffusivity contrasts for microscopic characterization of automotive brake pads KW - Antimony sulphide KW - Polybutadiene KW - Phenolic resin KW - SFM/AFM KW - Friction KW - Thermal diffusivity PY - 2002 DO - https://doi.org/10.1002/sia.1171 SN - 0142-2421 SN - 1096-9918 VL - 33 IS - 2 SP - 100 EP - 107 PB - Wiley CY - Chichester AN - OPUS4-1293 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Frunza, S. A1 - Frunza, L. A1 - Goering, Harald A1 - Sturm, Heinz T1 - On the dynamics of surface layer in octylcyanobiphenyl-aerosil systems N2 - A broadband dielectric study of the dispersions of silica spheres (Aerosil 380) in octylcyanobiphenyl (8CB) with densities between 0.083 and 10 g of silica per 1 cm3 of liquid crystal (LC) is reported. High values of silica densities were achieved for the first time to observe the behaviour of the LC monolayer on the surface of the silica particles. The relaxation characteristic of the bulk LC is noticed especially for the samples with low silica densities. Additionally, a slow relaxation was detected, even at temperatures for which the bulk LC is in the crystalline state. It was assigned to the surface layer of LC molecules. Remarkably, the temperature dependence of the relaxation rates for this slow process shows a behaviour typical for glass-forming liquids. PY - 2001 DO - https://doi.org/10.1209/epl/i2001-00591-8 SN - 0302-072X SN - 0295-5075 SN - 1286-4854 VL - 56 IS - 6 SP - 801 EP - 807 PB - EDP Science CY - Les-Ulis Cedexa, France AN - OPUS4-1572 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Von makroskopischen Fragestellungen und mikroskopischen Untersuchungsmethoden in der Tribologie T2 - Kolloquium "Synergie von Werkstoff- und Prozesstechnik" CY - Berlin, Germany DA - 2010-06-04 PY - 2010 AN - OPUS4-21617 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chung, Jae Un A1 - Munz, Martin A1 - Sturm, Heinz T1 - Stiffness variation in the interphase of amine-cured epoxy adjacent to copper microstructures N2 - In an effort to expand the understanding of the mechanical properties of the polymeric interphase on a metal surface, a composite consisting of epoxy and copper was prepared and analyzed. Scanning force microscopy-based force modulation microscopy (SFM-FMM) was employed along with dynamic mechanical analysis (DMA) and energy dispersive X-ray analysis (EDX). Diglycidyl ether of bisphenol A (DGEBA)-based epoxy resins were applied with amine curing agents. The samples were made taking advantage of electron beam lithography (EBL) in order to produce sharp edges of copper structures and a flat surface suitable for the SFM-FMM analysis, which was able to depict the stiffness within the interphase. It is considered significant information because the mechanical characteristic within the narrow interphase was revealed. Comparing with DMA and EDX, the stiffness information of SFM-FMM demonstrated a matching correlation and agreement in terms of preferential adsorption of the curing agent in the vicinity of the interface. The stiffness profiles of the two epoxy systems turned out to be different, and it shows the material dependence of the interphase characteristics. KW - Polymer-metal KW - Interphase KW - Stiffness KW - SFM/AFM KW - DMA KW - EDX KW - Epoxy KW - Copper PY - 2007 SN - 0142-2421 SN - 1096-9918 VL - 39 IS - 7 SP - 624 EP - 633 PB - Wiley CY - Chichester AN - OPUS4-14973 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munz, Martin A1 - Sturm, Heinz T1 - The Normal Force Modulation as a method for Studying the Interphase of Fibre Reinforced Polymer T2 - 24th Intern. TopoMetrix-Workshop: Aktuelle Entwicklungen in der Nanotechnologie und Rastersondenmikroskopie, Humboldt-Universität CY - Berlin, Germany DA - 1998-03-12 PY - 1998 AN - OPUS4-6457 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Untersuchungen zur Materialzusammensetzung der Oberfläche eines Polymerblends: Eine vergleichende Studie zur Aussagefähigkeit mechanischer und elektrischer Zusatzkontraste im SFM T2 - Diskussionstagung: Raster-Sonden-Mikroskopien und Organische Materialien V CY - Münster, Germany DA - 1996-10-09 PY - 1996 AN - OPUS4-6391 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Modulated lateral force microscopy: an AFM tool for analysis and modification of polymer surfaces T2 - Viennano 2007, Tagung des österreichischen Tribologenverbands CY - Vienna, Austria DA - 2007-03-14 PY - 2007 AN - OPUS4-18130 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Dynamic Plowing Lithography T2 - International Workshop on Scanning Probe Microscopy in Nanotechnology CY - Wroclaw, Poland DA - 2001-07-09 PY - 2001 AN - OPUS4-6514 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - SFM inside ESEM: A study of the electric properties of Polyaniline T2 - Polydays 2002 CY - Berlin, Germany DA - 2002-09-30 PY - 2002 AN - OPUS4-6538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tavares, L. A1 - Kjelstrup-Hansen, J. A1 - Rubahn, H.-G. A1 - Sturm, Heinz T1 - Reduced bleaching in organic nanofibers by bilayer polymer/oxide coating N2 - Para-hexaphenylene (p-6P) molecules exhibit a characteristic photoinduced reaction (bleaching) resulting in a decrease in luminescence intensity upon UV light exposure, which could render the technological use of the nanofibers problematic. In order to investigate the photoinduced reaction in nanofibers, optical bleaching experiments have been performed by irradiating both pristine and coated nanofibers with UV light. Oxide coating materials (SiOx and Al2O3) were applied onto p-6P nanofibers. These treatments caused a reduction in the bleaching reaction but in addition, the nanofiber luminescence spectrum was significantly altered. It was observed that some polymer coatings [a statistical copolymer of tetrafluoroethylene and 2,2-bis-trifluoromethyl-4,5-difluoro-1,3-dioxole, P(TFE-PDD), and poly(methyl methacrylate), PMMA] do not interfere with the luminescence spectrum from the p-6P but are not effective in stopping the bleaching. Bilayer coatings with first a polymer material, which should work as a protection layer to avoid modifications of the p-6P luminescence spectrum, and second an oxide layer used as oxygen blocker were tested and it was found that a particular bilayer polymer/oxide combination results in a significant reduction in bleaching without affecting significantly the emission spectrum from the nanofibers. KW - Nanofibers KW - Photobleaching KW - Polymer coating KW - Oxide coating PY - 2010 DO - https://doi.org/10.1063/1.3427561 SN - 0021-8979 SN - 1089-7550 VL - 107 SP - 103521-1 - 103521-6 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-21574 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cappella, Brunero A1 - Sturm, Heinz A1 - Schulz, Eckhard T1 - Stiffness and adhesion characterization of nanolithographed poly(methyl methacrylate) by means of force-displacement curves N2 - Poly(methyl methacrylate) (PMMA) surfaces have been modified by dynamic plowing lithography. The resulting modified structures, presenting regions of different densities and stiffnesses, have been studied by force–displacement curves. The elasto-plastic response, the stiffness, and the adhesion of the modified samples have been characterized. Force–displacement curves are able to distinguish between unmodified PMMA and two different structures resulting from the lithography, i.e. compressed PMMA and low density PMMA. In particular, the low density regions are made up of cluster-like globular particles, whose elasto-plastic response and adhesion are measured and whose contribution to the total elasto-plastic response and to the adhesion has been studied in detail. KW - AFM KW - Lithography KW - Force-displacement curves KW - Stiffness KW - Adhesion KW - Elasto-plastic response PY - 2002 DO - https://doi.org/10.1163/156856102760136472 SN - 0169-4243 SN - 1568-5616 VL - 16 IS - 7 SP - 921 EP - 933 PB - VNU Science Press CY - Utrecht AN - OPUS4-1609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maibohm, C. A1 - Brewer, J.R. A1 - Sturm, Heinz A1 - Balzer, F. A1 - Rubahn, H.-G. T1 - Bleaching and coating of organic nanofibers N2 - Based on an analysis of the diffusive heat flow equation, we determine limits on the localization of heating of soft materials and biological tissues by electromagnetically excited nanoparticles. For heating by rf magnetic fields or heating by typical continuous wave lasers, the local temperature rise adjacent to magnetic or metallic nanoparticles is negligible. However, heat dissipation for a large number of nanoparticles dispersed in a macroscopic region of a material or tissue produces a global temperature rise that is orders of magnitude larger than the temperature rise adjacent to a single nanoparticle. One approach for producing a significant local temperature rise on nanometer length scales is heating by high-power pulsed or modulated lasers with low duty cycle. KW - Nanofibers KW - Degradation KW - Bleaching KW - Luminescence KW - Silicon monoxide KW - Diffusion barrier KW - Security labels PY - 2006 DO - https://doi.org/10.1063/1.2335783 SN - 0021-8979 SN - 1089-7550 VL - 100 SP - 054304-1 - 054304-6 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-12761 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Imaging and simulation of mode shapes and harmonics of AFM cantilevers using Scanning Electron Microscopy T2 - 4th Multifrequency AFM Conference CY - Madrid, Spain DA - 2012-10-15 PY - 2012 AN - OPUS4-27342 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Messung elektrischer Eigenschaften in der Rastersondenmikroskopie T2 - Universität Ulm CY - Ulm, Germany DA - 1996-08-02 PY - 1996 AN - OPUS4-6398 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Bachelier, G. A1 - Siegel, J. A1 - Solis, J. A1 - Sturm, Heinz T1 - Time- and space-resolved dynamics of ablation and optical breakdown induced by femtosecond laser pulses in indium phosphide N2 - Femtosecond time-resolved microscopy has been used to analyze the structural transformation dynamics (melting, ablation, and solidification phenomena) induced by single intense 130 fs laser pulses in single-crystalline (100)-indium phosphide wafers in air on a time scale from ~100 fs up to 8 ns. In the ablative regime close to the ablation threshold, transient surface reflectivity patterns are observed by fs microscopy on a ps to ns time scale as a consequence of the complex spatial density structure of the ablating material (dynamic Newton fringes). At higher fluences, exceeding six times the ablation threshold, optical breakdown causes another, more violent ablation regime, which reduces the energy deposition depth along with the time of significant material removal. As a consequence, ablation lasts longer in a ring-shaped region around the region of optical breakdown. This leads to the formation of a crater profile with a central protrusion. In the melting regime below the ablation threshold, the melting dynamics of indium phosphide has been quantified and subsequent superficial amorphization has been observed upon solidification on the ns time scale leading to amorphous layer thicknesses of the order of a few tens of nanometers. KW - Femtosecond laser pulse KW - Indium Phosphide KW - Ablation KW - Surface reflectivity KW - Fs-time resolved microscopy KW - Scanning Force Microscopy PY - 2008 DO - https://doi.org/10.1063/1.2885105 SN - 0021-8979 SN - 1089-7550 VL - 103 IS - 5 SP - 054910-1 EP - 054910-6 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-17090 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sturm, Heinz A1 - Schröter, Maria-Astrid A1 - Weimann, Christiane T1 - Imaging method for vibrating scanning force microscopy cantilevers for the analysis of mode shapes and nonlinear harmonic motion N2 - A specially designed scanning force microscope (SFM, atomic force microscope – AFM) was incorporated into the chamber of a commercial scanning electron microscope (SEM) to investigate vibrating SFM cantilevers at their resonance. Inherently, the spatial resolution of electron microscopy is higher than that of optical methods. In this paper we present vibration modes (eigenmodes) of two different SFM cantilevers. Their nonlinear behavior is also explored in order to depict their 2nd harmonics (twice the fundamental frequency). Imaging of the local vibration is performed by measuring the frequency- and phase-selective responses of the SE signal at different X and Y positions of the scanned electron beam. KW - Electron microscopy KW - Scanning force microscopy KW - Motion detection KW - Cantilever KW - Eigenmode KW - Harmonic KW - Nonlinearity KW - Harmonix cantilever PY - 2012 DO - https://doi.org/10.1016/j.mee.2012.07.088 SN - 0167-9317 SN - 1873-5568 VL - 98 SP - 492 EP - 496 PB - Elsevier Science CY - Amsterdam, Netherlands AN - OPUS4-26431 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sturm, Heinz A1 - Cappella, Brunero A1 - Heyde, M. A1 - Ritter, C. A1 - Rademann, K. T1 - Dislocation of antimony clusters on graphite by means of dynamic plowing nanolithography N2 - Antimony clusters of different shapes and dimensions have been obtained by evaporating antimony on graphite. The dependence of the shape and dimensions of the particles on the evaporation parameters (effective layer thickness, temperature, pressure) is discussed. A characterisation of the different structures is presented. In particular, the decoration of graphite steps is discussed. Clusters have been dislocated by means of dynamic plowing nanolithography, both in vector and in image pattern mode. The dependence of the energy needed to dislocate a cluster on its dimensions and position is discussed. KW - Antimony clusters KW - Nanolithography PY - 2001 DO - https://doi.org/10.1016/S0039-6028(00)01113-4 SN - 0039-6028 VL - 476 IS - 1-2 SP - 54 EP - 62 PB - Elsevier CY - Amsterdam AN - OPUS4-875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Harmonically modulated friction force microscopy: An AFM tool for analysis and modification of polymer surfaces T2 - International Symposium on Polymer Surface Characterization (MST conference) CY - Newark, NJ, USA DA - 2000-10-10 PY - 2000 AN - OPUS4-6505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Scanning Force Microscopy (SFM) of Polymer surfaces: Materials contrasts and nanolithography T2 - Fachbereich Chemie der Universität Siegen CY - Siegen, Germany DA - 2003-07-01 PY - 2003 AN - OPUS4-4100 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solomun, Tihomir A1 - Seitz, H. A1 - Sturm, Heinz T1 - Electron irradiation of immobilized DNA in solution through a silicon nano-membrane N2 - In fields involving irradiated aqueous solutions, such as radiotherapy and nuclear waste remediation, it is often unclear whether the principal reactive species are OH° radicals or secondary (low-energy) electrons. This is mostly because both are rapidly attenuated in water. Presently a large part of the evidence for the involvement of low-energy electrons in biological radiation damage is based on 'dry' DNA samples. We demonstrate irradiation of DNA in solution by direct injection of electrons through a 40-nm thin SiO2 membrane, followed by in-situ detection of the DNA damage by a fluorescence-based method. Corresponding Monte Carlo simulations show that the spatial distribution of ionizing events in water with respect to the membrane is controlled by the electron impact energy. By immobilizing DNA to the solution side of the membrane, and because dynamics and reaction ranges of OH° radicals and low-energy electrons are dramatically different, it is possible to tune into the OH° radical or into the electron 'reaction modes' by simply changing the electron impact energy. Such experiments have the potential to provide important information on the radio-sensitivity at a level of a single biomolecule and to contribute to the development of new dosage concepts. KW - Radiation chemistry KW - Low-energy electrons KW - DNA damage KW - Monte Carlo PY - 2013 DO - https://doi.org/10.1016/j.radphyschem.2013.02.035 SN - 0969-806X SN - 0020-7055 SN - 0146-5724 VL - 88 SP - 70 EP - 73 PB - Pergamon Press CY - Oxford [u.a.] ; Frankfurt, M. AN - OPUS4-30321 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henrichsen, H. A1 - Sturm, Heinz A1 - Boggild, P. A1 - Hansen, O. T1 - Submicron organic nanofiber devices with different anode-cathode materials: A simple approach N2 - The authors present a simple general method for simultaneously producing tens of submicron electrode gaps with different cathode and anode materials on top of nanofibers, nanowires, and nanotubes, with an optional gap size variation. Using this method, an ensemble of para-hexaphenylene (p6P) nanofiber devices of different length was fabricated with Sm and Au electrodes. The measured I-V characteristics are in agreement with a nonlinear hopping transport model, where domain barriers dominate the transport with an estimated domain size of 23±5 nm. KW - Nanofibers KW - Sub-micron electrode KW - Para-hexaphenylene KW - Samarium KW - Gold KW - I/V-characteristics KW - Nanolasers KW - Domain barriers PY - 2010 DO - https://doi.org/10.1116/1.3431088 SN - 1071-1023 SN - 0734-211X VL - 28 IS - 3 SP - 617 EP - 622 PB - American Institute of Physics CY - New York, NY AN - OPUS4-21573 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Scanning Probe Microscopy Techniques for the Examination of Interface Nanomechanics - A Study of Topography, AC Conductivity and Surface Stiffness T2 - Workshop: Rastersondenmikroskopie in Forschung und Industrie an der GH Wuppertal CY - Wuppertal, Germany DA - 1999-03-11 PY - 1999 AN - OPUS4-6497 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meyer-Plath, Asmus A1 - Beckert, F A1 - Tölle, FJ A1 - Sturm, Heinz A1 - Mülhaupt, R T1 - Stable aqueous dispersions of functionalized multi-layer graphene by pulsed underwater plasma exfoliation of graphite N2 - A process was developed for graphite particle exfoliation in water to stably dispersed multi-layer graphene. It uses electrohydraulic shockwaves and the functionalizing effect of solution plasma discharges in water. The discharges were excited by 100 ns high voltage pulsing of graphite particle chains that bridge an electrode gap. The underwater discharges allow simultaneous exfoliation and chemical functionalization of graphite particles to partially oxidized multi-layer graphene. Exfoliation is caused by shockwaves that result from rapid evaporation of carbon and water to plasma-excited gas species. Depending on discharge energy and locus of ignition, the shockwaves cause stirring, erosion, exfoliation and/or expansion of graphite flakes. The process was optimized to produce long-term stable aqueous dispersions of multi-layer graphene from graphite in a single process step without requiring addition of intercalants, surfactants, binders or special solvents. A setup was developed that allows continuous production of aqueous dispersions of flake size-selected multi-layer graphenes. Due to the well-preserved sp(2)-carbon structure, thin films made from the dispersed graphene exhibited high electrical conductivity. Underwater plasma discharge processing exhibits high innovation potential for morphological and chemical modifications of carbonaceous materials and surfaces, especially for the generation of stable dispersions of two-dimensional, layered materials. KW - Exfoliation KW - Graphene KW - Aqueous dispersion KW - Solution plasma KW - Functionalization KW - Electrohydraulic effect KW - Shear exfoliation KW - Oxide-films KW - Water PY - 2016 DO - https://doi.org/10.1088/0022-3727/49/4/045301 SN - 0022-3727 VL - 49 IS - 4 SP - 045301-1 EP - 045301-11 AN - OPUS4-35796 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Munz, Martin A1 - Chung, Jae Un A1 - Eltanany, Gehan A1 - Sturm, Heinz A1 - Schulz, Eckhard ED - Degischer, H.-P. T1 - Interphasial stiffness gradients in polymer materials T2 - Symposium Verbundwerkstoffe und Werkstoffverbunde CY - Wien, Österreich DA - 2003-07-02 PY - 2003 SN - 3-527-30762-1 PB - Wiley-VCH CY - Weinheim AN - OPUS4-2525 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Modulated Lateral Force Microscopy: An AFM tool for Analysis and Modification of Polymer T2 - German-Russian Workshop "Contact Mechanics and Friction" CY - Berlin, Germany DA - 2009-10-05 PY - 2009 AN - OPUS4-20751 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Rasterkraftmikroskopische Verfahren zur Beschreibung der Grenzflächen in Polymer-Kompositwerkstoffen T2 - Konferenz: Nanotechnologie für Faserkunststoffverbunde CY - Braunschweig, Germany DA - 2010-05-26 PY - 2010 AN - OPUS4-21616 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - How to write functional areas on polymers using DPL - a way to produce nanoarrays for life science applications T2 - iThemba LABS CY - Somerset West, South Africa DA - 2002-02-03 PY - 2002 AN - OPUS4-6528 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Scanning force mocroscopy based lothography T2 - JPK-Wirkshop "Scanning probe microscopy in life science" CY - Berlin, Germany DA - 2003-09-18 PY - 2003 AN - OPUS4-4653 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braun, Ulrike A1 - Bahr, Horst A1 - Sturm, Heinz A1 - Schartel, Bernhard T1 - Flame retardancy mechanisms of metal phosphinates and metal phosphinates in combination with melamine cyanurate in glass-fiber reinforced poly(1,4-butylene terephthalate): the influence of metal cation N2 - The pyrolysis and fire behavior of glass-fiber reinforced poly(butylene terephthalate) (PBT/GF) with two different metal phosphinates as flame retardants in combination with and without melamine cyanurate (MC) were analyzed by means of thermogravimetry, thermogravimetry coupled with infrared spectroscopy, flammability, and cone calorimeter tests as well as scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray fluorescence spectroscopy. In PBT/GF, dosages of 13-20% of the halogen-free flame retardant aluminum phosphinate or aluminum phosphinate in combination with MC fulfill the requirements for electrical engineering and electronics applications (UL 94 = V-0; LOI > 42%), whereas the use of the same amount of zinc phosphinate or zinc phosphinate in combination with MC does not improve the fire behavior satisfactorily (UL 94 = HB; LOI = 27-28%). The performance under forced flaming conditions (cone calorimeter) is quite similar for both of the metal phosphinates. The use of aluminum and zinc salts results in similar flame inhibition predominantly due to the release of the phosphinate compounds in the gas phase. Both metal phosphinates and MC interact with the polymer changing the decomposition characteristics. However, part of the zinc phosphinate vaporizes as a complete molecule. Because of the different decomposition behavior of the metal salts, only the aluminum phosphinate results in a small amount of thermally stable carbonaceous char. In particular, the aluminum phosphinate-terephthalate formed is more stable than the zinc phosphinate-terephthalate. The small amount of char has a crucial effect on the thermal properties and mechanical stability of the residue and thus the flammability. KW - Flame retardance KW - Polyester KW - Phosphinates KW - Pyrolysis KW - Cone calorimeter PY - 2008 DO - https://doi.org/10.1002/pat.1147 SN - 1042-7147 SN - 1099-1581 VL - 19 IS - 6 SP - 680 EP - 692 PB - John Wiley & Sons, Ltd. CY - Chichester AN - OPUS4-17620 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cappella, Brunero A1 - Sturm, Heinz A1 - Weidner, Steffen T1 - Breaking polymer chains by dynamic plowing lithography N2 - The adhesion of poly(methyl methacrylate) (PMMA) and polystyrene (PS) films, whose surface has been previously structured by dynamic plowing lithography (DPL), has been measured by means of force–displacement curves. The different adhesion of modified and unmodified PS leads to the assumption that polymer chains are broken during DPL. After measuring the energy dissipated by the tip during DPL, in order to check that the transferred energy is sufficient to break covalent bonds, the polymer chain scission caused by the lithographic process has been definitely confirmed by size exclusion chromatography measurements of the lithographed films. KW - AFM KW - Nanolithography KW - Chain scission PY - 2002 DO - https://doi.org/10.1016/S0032-3861(02)00285-9 SN - 0032-3861 SN - 1873-2291 VL - 43 IS - 16 SP - 4461 EP - 4466 PB - Springer CY - Berlin AN - OPUS4-1608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Rasterkraftmikroskopie auf Oberflächen polymerer Werkstoffe T2 - Berliner Polymeren-Tage CY - Potsdam, Germany DA - 1994-10-05 PY - 1994 AN - OPUS4-6371 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Reibungsmikroskopie auf laserabladierten C-Faser-Verbunden und plasmapolymerisierten dünnen Schichten T2 - Tagung "Raster-Sonden-Mikroskopien und organische Materialien II" CY - Mainz, Germany DA - 1993-10-11 PY - 1993 AN - OPUS4-6380 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Silbernagl, Dorothee A1 - Sturm, Heinz A1 - Cappella, Brunero T1 - Influence of film-substrate adhesion on the mechanical properties of thin polymer films KW - Adhesion KW - AFM KW - Thin film KW - Mechanical properties KW - Force-distance curves PY - 2009 DO - https://doi.org/10.1021/la8041007 SN - 0743-7463 SN - 1520-5827 VL - 25 IS - 9 SP - 5091 EP - 5097 PB - American Chemical Society CY - Washington, DC AN - OPUS4-19363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Nanotribology and vibrating contacts T2 - Chinese-German Symposium Nanomanufacturing and Nanotribology CY - Berlin, Germany DA - 2011-05-30 PY - 2011 AN - OPUS4-23582 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Munz, Martin A1 - Sturm, Heinz T1 - Structure formation on the surface of indium phosphide irradiated by femtosecond laser pulses N2 - Laser-induced periodic surface structures (LIPSS; ripples) with different spatial characteristics have been observed after irradiation of single-crystalline indium phosphide (c-InP) with multiple linearly polarized femtosecond pulses (130 fs, 800 nm) in air. With an increasing number of pulses per spot, N, up to 100, a characteristic evolution of two different types of ripples has been observed, i.e., (i) the growth of a grating perpendicular to the polarization vector consisting of nearly wavelength-sized periodic lines and (ii), in a specific pulse number regime (N = 5-30), the additional formation of equally oriented ripples with a spatial period close to half of the laser wavelength. For pulse numbers higher than 50, the formation of micrometer-spaced grooves has been found, which are oriented perpendicular to the ripples. These topographical surface alterations are discussed in the frame of existing LIPSS theories. KW - Femtosecond laser irradiation KW - Indium phosphide KW - Microstructure KW - Laser induced periodic surface structures KW - LIPSS KW - SEM PY - 2005 DO - https://doi.org/10.1063/1.1827919 SN - 0021-8979 SN - 1089-7550 VL - 97 SP - 1 EP - 9 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-5992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Technology transfer of a new developed exploratory Scanning Force Microscope, fine-tuned to meet the demands of the upcoming Nanobiotechnology industries T2 - International Forum On Project Development, Industrial Heritage Program CY - Bologna, Italy DA - 2005-02-28 PY - 2005 AN - OPUS4-6976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Messung elektrischer Eigenschaften in der Rasterkraftmikroskopie: Leitfähigkeitskontrast auf Kohlefaseroberflächen T2 - Tagung "Raster-Sonden-Mikorskopien und organische Materialien IV" CY - Munich, Germany DA - 1995-10-11 PY - 1995 AN - OPUS4-6388 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Analysis of Scanning Probe Microscopy (SPM) Piezos T2 - Digital-Instruments User-Workshop an der TU Dresden CY - Dresden, Germany DA - 1999-04-07 PY - 1999 AN - OPUS4-6498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braun, Ulrike A1 - Lorenz, Edelgard A1 - Weimann, Christiane A1 - Sturm, Heinz A1 - Karimov, I. A1 - Ettl, J. A1 - Meier, R. A1 - Wohlgemuth, W. A. A1 - Berger, H. A1 - Wildgruber, M. T1 - Mechanic and surface properties of central-venous port catheters after removal: A comparison of polyurethane and Silicon rubber materials N2 - Central venous port devices made of two different polymeric materials, thermoplastic polyurethane (TPU)and silicone rubber (SiR), were compared due their material properties. Both naïve catheters as well as catheters after removal from patients were investigated. In lab experiments the influence of various chemo-therapeutic solutions on material properties was investigated, where as the samples after removal were compared according to the implanted time inpatient. The macroscopic,mechanical performance was assessed with dynamic, specially adapted tests for elasticity. The degradation status of the materials was determined with common tools of polymer characterisation, such as infrared spectroscopy, molecular weight measurements and various methods of thermal analysis. The surface morphology was an alysed using scanning electron microscopy. A correlation between material properties and clinical performance was proposed. The surface morphology and chemical composition of the polyurethane catheter materials can potentially result in increased susceptibility of the catheter to bloodstream infections and thrombotic complications. The higher mechanic failure,especially with increasing implantation time of the silicone catheters is related to the lower mechanical performance compared to the polyurethane material as well as loss of barium sulphate filler particles near the surface of the catheter. This results in preformed microscopic notches, which act as predetermined sites of fracture. KW - Thermoplastic polyurethane (TPU) KW - Silicone rubber (SiR) KW - Catheters KW - Central venous access port KW - Complication KW - Structure propertyrelationship KW - Mechanical testing PY - 2016 DO - https://doi.org/10.1016/j.jmbbm.2016.08.002 SN - 1751-6161 SN - 1878-0180 VL - 64 SP - 281 EP - 291 PB - Elsevier Ltd. AN - OPUS4-37178 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munz, Martin A1 - Sturm, Heinz A1 - Schulz, Eckhard A1 - Hinrichsen, G. T1 - The scanning force microscope as a tool for the detection of local mechanical properties within the interphase of fibre reinforced polymers N2 - Scanning force microscopy (SFM) has been used to assess the local mechanical properties of fibre-reinforced polymers. Using a sinusoidal displacement modulation (DM) and lock-in technique the method allows to characterize local viscoelastic properties with a high lateral resolution. The simultaneous measurement of the local electrical conductivity is proposed which facilitates the interpretation of the mechanical data. The investigation of cross-sections perpendicular to the axis of carbon fibres embedded in PPS delivers some information about the change in local stiffness within the interfacial region. As a first approach, assuming a single-exponential decrease in local stiffness along a radial line from fibre to polymer we find characteristic decay lengths which are distributed in a range between 20 and 80nm. Further, a modified DM-mode is proposed which is expected to provide a contrast enhancement of the signal which is related to local stiffness. This can be achieved by installing an additional feedback loop which keeps constant the amplitude of dynamic indentation (CDI-mode). KW - Polymer-matrix composites (PMC´s) KW - Interface/interphase KW - SFM/AFM KW - Surface properties KW - Nondestructive testing PY - 1998 DO - https://doi.org/10.1016/S1359-835X(98)00077-3 SN - 1359-835X VL - 29 SP - 1251 EP - 1259 PB - Elsevier CY - Oxford AN - OPUS4-1294 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Sturm, Heinz A1 - Geuss, Markus A1 - Schulz, Eckhard ED - Konsta, A. T1 - Scanning force microscopy investigations on electroactive polymer films N2 - The authors present investigations on a PVDF (polyvinylidenefluoride) film supplied with top and bottom Au electrodes, which is analysed using a SFM and a contactless optical sensor to measure the sample strain with respect to applied fields. T2 - 10th IEEE International Symposium on Electrets (ISE) CY - Delphi, Greece DA - 1999-09-22 PY - 1999 SN - 0-7803-5025-1 DO - https://doi.org/10.1109/ISE.1999.832086 SP - 465 EP - 468 PB - IEEE Operations Center CY - Piscataway, NJ AN - OPUS4-6862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - AFM cantilevers as mechanical sensors T2 - Nano-Seminar am NanoSYD-Institut der süddänischen Universität in Sonderborg CY - Sonderborg, Denmark DA - 2008-12-02 PY - 2008 AN - OPUS4-18266 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solomun, Tihomir A1 - Schimanski, A. A1 - Sturm, Heinz A1 - Illenberger, E. T1 - Reactions of amide group with fluorine as revealed with surface analytics N2 - Thin polyamide-6 films were exposed to fluorine gas and analysed with photoelectron and infrared spectroscopies. Fluorine cleaves the amide C–N bond resulting in the formation of the –COOH and –NF2 terminal groups. This is evident from large shifts in the N1s binding energy (+5 eV) and C=O stretching frequency (~80 cm-1), appearance of ester oxygen in the XPS spectra, as well as by the 19F nmr spectra of volatile products consistent with a terminal NF2 group. KW - Gasfluorierung KW - Polyamid-6 KW - XPS KW - IR KW - -COOH und NF2-Gruppen PY - 2004 UR - http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235231%232004%23996109995%23499295%23FLA%23&_cdi=5231&_pubType=J&_auth=y&_acct=C000049503&_version=1&_urlVersion=0&_userid=963821&md5=baea8e0df63660c666921ef377c00e40 SN - 0009-2614 SN - 1873-4448 VL - 378 SP - 312 EP - 316 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-3439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Solomun, Tihomir A1 - Seitz, H. A1 - Sturm, Heinz T1 - DNA damage by low-energy electron impact: dependence on guanine content KW - DNA oligonucleotide KW - Low energy electrons KW - Secondary electrons KW - Damage KW - Guanine content PY - 2009 DO - https://doi.org/10.1021/jp905263x SN - 1520-6106 SN - 1089-5647 VL - 113 IS - 34 SP - 11557 EP - 11559 PB - Soc. CY - Washington, DC AN - OPUS4-20704 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Nichtlinearität und Hysterese von AFM-Piezos T2 - 24th Intern. TopoMetrix-Workshop: Aktuelle Entwicklungen in der Nanotechnologie und Rastersondenmikroskopie, Humboldt-Universität CY - Berlin, Germany DA - 1998-03-12 PY - 1998 AN - OPUS4-6462 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Lithography on Polymers using a Scanning Force Microscope (SFM) and a Environmental Scanning Electron Microscope (ESEM) T2 - Seminar International PhD Program CY - Berlin, Germany DA - 2004-04-30 PY - 2004 AN - OPUS4-3504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Rastersondenverfahren T2 - BAM, DGM Fachausschuss "Gefüge und Eigenschaften von Polymerwerkstoffen" CY - Berlin, Germany DA - 2003-12-05 PY - 2003 AN - OPUS4-4099 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Dynamics of phase transitions in polymer thin films upon single femtosecond laser pulse irradiation T2 - Second International Conference on Photo-Induced Phase Transitions Cooperative, non-linear and functional properties CY - Rennes, France DA - 2005-05-24 PY - 2005 AN - OPUS4-7430 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sturm, Heinz A1 - Schulz, Eckhard T1 - Atomic force microscopy with simultaneous AC conductivity contrast for the analysis of carbon fibre surfaces KW - Carbon fibre KW - Surface analysis KW - Conductivity microscopy KW - Scanning force microscopy KW - Scanning tunneling microscopy KW - Fiber surfaces PY - 1996 SN - 1359-835X VL - 27 IS - 9 SP - 677 EP - 684 PB - Elsevier CY - Oxford AN - OPUS4-6849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munz, Martin A1 - Sturm, Heinz A1 - Schulz, Eckhard T1 - Zuverlässigkeit von Polymer-Werkstoffen - Interphasen nanoskopisch betrachtet T2 - 3. Workshop "Rasterkraftmikroskopie in der Werkstoffwissenschaft" CY - Berlin, BAM, Deutschland DA - 2002-02-28 PY - 2002 SP - 14 AN - OPUS4-1831 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Lithographie, Manipulation und Analyse in ESEM und AFM T2 - Evaluierungsmeeting eines zukünftigen DFG-Forscherverbundes zum Thema "Nanoröhren und -drähte" CY - Halle (Saale), Germany DA - 2003-01-17 PY - 2003 AN - OPUS4-2915 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz T1 - Atomic force microscopy with simultaneous AC conductivity contrast for the analysis of carbon fibre surfaces T2 - IPCM (Interfacial Phenomena in Composite Materials) CY - Eindhoven, Netherlands DA - 1995-09-10 PY - 1995 AN - OPUS4-6385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dümichen, Erik A1 - Javdanitehran, M. A1 - Erdmann, Maren A1 - Trappe, Volker A1 - Sturm, Heinz A1 - Braun, Ulrike A1 - Ziegmann, G. T1 - Analyzing the network formation and curing kinetics of epoxy resins by in situ near-infrared measurements with variable heating rates N2 - Near-infrared spectroscopy (NIR) turned out to be well suited for analyzing the degree of cure for epoxy systems. In contrast to dynamic scanning calorimetry (DSC), where the released heat of reaction determines the degree of epoxy conversion indirectly, NIR spectroscopy is able to determine the conversion directly by analyzing structural changes. Therefore, a new heatable NIR cell was equipped with an integrated thermocouple, which enables the real sample temperature to be controlled and monitored in situ during epoxy curing. Dynamic scans at different heating rates were used for kinetic modelling, to define kinetic parameters and to predict real curing processes. The kinetic models and their parameters were validated with an isothermal and a more complex multi-step curing scenario. Two available commercial epoxy systems based on DGEBA were used with an anhydride and with an amine hardener. NIR results were compared with DSC data. The simulated conversion predicted with a model fitted on the basis of NIR and DSC dynamic scans showed good agreement with the conversion measured in the isothermal curing validation test. Due to the proven reliability of NIR in measuring the reaction progress of curing, it can be considered a versatile measurement system for in situ monitoring of component production in the automotive, aerospace and wind energy sectors. KW - Epoxy resins KW - Curing kinetics KW - Near-infrared spectroscopy KW - DSC PY - 2015 DO - https://doi.org/10.1016/j.tca.2015.08.008 SN - 0040-6031 SN - 1872-762X VL - 616 SP - 49 EP - 60 PB - Elsevier CY - Amsterdam AN - OPUS4-34187 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -