TY - CONF
A1 - Pech May, Nelson Wilbur
A1 - Paul, A.
A1 - Ziegler, Mathias
T1 - Pulse-compression laser thermography using a modified Barker code: Enhanced detection of subsurface defects
N2 - Pulse-compression thermography is an emerging technique that has shown versatility by combination of pulsed and lock-in thermography. Accordingly, several aspects of this technique are still unexplored, and some others not fully developed yet. Barker codes were widely used in radar applications due to their simplicity and their optimum autocorrelation function. Nevertheless, applications were limited by the amplitude of the sidelobes present in the autocorrelation function and therefore, several filters have been developed which aim to reduce the sidelobes. However, the filters usually depend on empirical parameters which must be determined for each application. A better alternative would improve the applicability of the Barker codes. In this work, we further develop the pulse-compression thermography technique by introducing a 13-bit modified Barker code (mBC): This allows to drastically reduce the sidelobes characteristic of the 13-bit Barker code (BC). Consequently, the thermographic impulse response, obtained by cross-correlation, is almost free of such sidelobes. Deeper defects become easier to detect in comparison with using a 13-bit Barker code. Numerical simulations using the finite element method are used for comparison and experimental measurements are performed in a sample of steel grade St 37 with machined notches of three different depths: 2 mm, 4 mm and 6 mm.
T2 - SPIE Defense + Commercial Sensing 2021
CY - Online meeting
DA - 13.04.2021
KW - Pulse-compression laser thermography
KW - Barker codes
KW - Non-destructive testing
PY - 2021
DO - https://doi.org/10.1117/12.2586078
SN - 0277-786X
VL - 11743
SP - 1
EP - 11
PB - SPIE
CY - Bellingham, Wash.
AN - OPUS4-53247
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Pech May, Nelson Wilbur
A1 - Paul, A.
A1 - Ziegler, Mathias
T1 - Pulse-compression laser thermography using a modified Barker code: Enhanced detection of subsurface defects
N2 - Pulse-compression thermography is an emerging technique that has shown versatility by combination of pulsed and lock-in thermography. Accordingly, several aspects of this technique are still unexplored, and some others not fully developed yet. Barker codes were widely used in radar applications due to their simplicity and their optimum autocorrelation function. Nevertheless, applications were limited by the amplitude of the sidelobes present in the autocorrelation function and therefore, several filters have been developed which aim to reduce the sidelobes. However, the filters usually depend on empirical parameters which must be determined for each application. A better alternative would improve the applicability of the Barker codes. In this work, we further develop the pulse-compression thermography technique by introducing a 13-bit modified Barker code (mBC): This allows to drastically reduce the sidelobes characteristic of the 13-bit Barker code (BC). Consequently, the thermographic impulse response, obtained by cross-correlation, is almost free of such sidelobes. Deeper defects become easier to detect in comparison with using a 13-bit Barker code. Numerical simulations using the finite element method are used for comparison and experimental measurements are performed in a sample of steel grade St 37 with machined notches of three different depths: 2 mm, 4 mm and 6 mm.
T2 - SPIE Defense + Commercial Sensing 2021
CY - Online meeting
DA - 13.04.2021
KW - Pulse-compression laser thermography
KW - Barker codes
KW - Non-destructive testing
PY - 2021
AN - OPUS4-53249
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Singh, S.
A1 - Palani, I. A.
A1 - Paul, C. P.
A1 - Funk, Alexander
A1 - Gokuldoss, P. K.
T1 - Wire Arc Additive Manufacturing of NiTi 4D Structures: Influence of Interlayer Delay
N2 - Shape memory alloy structures for actuator and vibration damper applications may be manufactured using wire arc additive manufacturing (W AAM), which is one of the additive manufacturing technologies. Multilayer deposition causes heat accumulation during W AAM, which rises the preheat temperature of the previously created layer. This leads to process instabilities, which result in deviations from the desired dimensions and mechanical properties changes. During W AAM deposition of the wall structure, a systematic research is carried out by adjusting the interlayer delay from 10 to 30 s. When the delay period is increased from 10 to 30 s, the breadth decreases by 45% and the height increases by 33%. Grain refinement occurs when the interlayer delay duration is increased, resulting in better hardness, phase transformation temperature, compressive strength, and shape recovery behavior. This study shows how the interlayer delay affects the behavior of W AAM-built nickel-titanium alloy (NiTi) structures in a variety of applications.
KW - Wire are additive manufacturing
KW - Shape memory alloy
KW - Nitinol
KW - Interlayer delay
PY - 2022
DO - https://doi.org/10.1089/3dp.2021.0296
SN - 2329-7662
SP - 1
EP - 11
PB - Liebert
CY - New Rochelle, NY
AN - OPUS4-55795
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kittner, Maria
A1 - Kerndorff, A.
A1 - Ricking, M.
A1 - Bednarz, M.
A1 - Obermaier, N.
A1 - Lukas, M.
A1 - Asenova, M.
A1 - Bordós, G.
A1 - Eisentraut, Paul
A1 - Hohenblum, P.
A1 - Hudcova, H.
A1 - Humer, F.
A1 - István, T. G.
A1 - Kirchner, M.
A1 - Marushevska, O.
A1 - Nemejcová, D.
A1 - Oswald, P.
A1 - Paunovic, M.
A1 - Sengl, M.
A1 - Slobodnik, J.
A1 - Spanowsky, K.
A1 - Tudorache, M.
A1 - Wagensonner, H.
A1 - Liska, I.
A1 - Braun, U.
A1 - Bannick, C. G.
T1 - Microplastics in the Danube River Basin: A First Comprehensive Screening with a Harmonized Analytical Approach
N2 - In this study, carried out within the Joint Danube Survey 4, a comprehensive microplastic screening in the water column within a large European river basin from its source to estuary, including major tributaries, was realized. The objective was to develop principles of a systematic and practicable microplastic monitoring strategy using sedimentation boxes for collection of suspended particulate matter followed by its subsequent analysis using thermal extraction desorption-gas chromatography/mass spectrometry. In total, 18 sampling sites in the Danube River Basin were investigated. The obtained suspended particulate matter samples were subdivided into the fractions of >100 μm and <100 μm and subsequently analyzed for microplastic mass contents. The results showed that microplastics were detected in all samples, with polyethylene being the predominant polymer with maximum contents of 22.24 μg/mg, 3.23 μg/mg for polystyrene, 1.03 μg/mg for styrene-butadiene-rubber, and 0.45 μg/mg for polypropylene. Further, polymers such as different sorts of polyester, polyacrylates, polylactide, and natural rubber were not detected or below the detection limit. Additional investigations on possible interference of polyethylene signals by algae-derived fatty acids were assessed. In the context of targeted monitoring, repeated measurements provide more certainty in the interpretation of the results for the individual sites. Nevertheless, it can be stated that the chosen approach using an integrative sampling and determination of total plastic content proved to be successful.
KW - Thermal extraction desorption-gas chromatography/mass spectrometry (TED-GC/MS), monitoring
KW - Microplastics
KW - River
KW - Suspended particulate matter (SPM)
KW - Sedimentation box (SB)
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551444
DO - https://doi.org/10.1021/acsestwater.1c00439
VL - 2
IS - 7
SP - 1174
EP - 1181
PB - ACS Publications
AN - OPUS4-55144
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Godard, A.
A1 - Kalot, G.
A1 - Privat, M.
A1 - Bendellaa, M.
A1 - Busser, B.
A1 - Wegner, Karl David
A1 - Denat, F.
A1 - Le Guevel, X.
A1 - Coll, J.-L.
A1 - Paul, C.
A1 - Bodio, E.
A1 - Goze, C.
A1 - Sancey, L.
T1 - NIR-II Aza-BODIPY Dyes Bioconjugated to Monoclonal Antibody Trastuzumab for Selective Imaging of HER2-Positive Ovarian Cancer
N2 - Using fluorescence-guided surgery (FGS) to cytoreductive surgery helps achieving complete resection of microscopic ovarian tumors. The use of visible and NIR-I fluorophores has led to beneficial results in clinical trials; however, involving NIR-II dyes seems to outperform those benefits due to the deeper tissue imaging and higher signal/noise ratio attained within the NIR-II optical window. In this context, we developed NIR-II emitting dyes targeting human epidermal growth factor receptor 2 (HER2)-positive ovarian tumors by coupling water-soluble NIR-II aza-BODIPY dyes to the FDA-approved anti-HER2 antibody, namely, trastuzumab. These bioconjugated NIR-II-emitting dyes displayed a prolonged stability in serum and a maintained affinity toward HER2 in vitro. We obtained selective targeting of HER2 positive tumors (SKOV-3) in vivo, with a favorable tumor accumulation. We demonstrated the fluorescence properties and the specific HER2 binding of the bioconjugated dyes in vivo and thus their potential for NIR-II FGS in the cancer setting.
KW - NIR-II
KW - Fluorescent dye
KW - In vivo imaging
KW - Ovarian cancer
KW - Antibody conjuagtes
KW - Bioimaging
PY - 2023
DO - https://doi.org/10.1021/acs.jmedchem.3c00100
SN - 0022-2623
VL - 66
IS - 7
SP - 5185
EP - 5195
PB - ACS Publications
AN - OPUS4-57293
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chazeau, E.
A1 - Fabre, C.
A1 - Privat, M.
A1 - Godard, A.
A1 - Racoeur, C.
A1 - Bodio, E.
A1 - Busser, B.
A1 - Wegner, Karl David
A1 - Sancey, L.
A1 - Paul, C.
A1 - Goze, C.
T1 - Comparison of the In Vitro and In Vivo Behavior of a Series of NIR-II-Emitting Aza-BODIPYs Containing Different Water-Solubilizing Groups and Their Trastuzumab Antibody Conjugates
N2 - The development of new fluorescent organic probes effective in the NIR-II region is currently a fast-growing field and represents a challenge in the domain of medical imaging. In this study, we have designed and synthesized an innovative series of aza-boron dipyrromethenes emitting in the NIR-II region. We have investigated the effect of different water-solubilizing groups not only on the photophysical properties of the compounds but also on their in vitro and in vivo performance after bioconjugation to the antibody trastuzumab. Remarkably, we discovered that the most lipophilic compound unexpectedly displayed the most favorable in vivo properties after bioconjugation. This underlines the profound influence that the fluorophore functionalization approach can have on the efficiency of the resulting imaging agent.
KW - NIR-II
KW - In vivo imaging
KW - Fluorescence
KW - Spectroscopy
KW - Antibody conjugates
PY - 2024
DO - https://doi.org/10.1021/acs.jmedchem.3c02139
SN - 1520-4804
VL - 67
IS - 5
SP - 3679
EP - 3691
PB - ACS Publications
CY - Washington, DC
AN - OPUS4-59607
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Davison, Nathan
A1 - Hemingway, Jack M.
A1 - Wills, Corinne
A1 - Stolar, Tomislav
A1 - Waddell, Paul G.
A1 - Dixon, Casey M.
A1 - Barron, Luke
A1 - Dawson, James A.
A1 - Lu, Erli
T1 - Mechanochemical Synthesis of a Sodium Anion Complex [Na+(2,2,2-cryptand)Na–] and Studies of Its Reactivity: Two-Electron and One-Electron Reductions
N2 - Group 1 metal molecular chemistry is dominated by a +1 oxidation state, while a 0 oxidation state is widespread in the metals. A more exotic, yet still available, oxidation state of group 1 metal is −1, i.e., alkalide. Reported as early as the 1970s, the alkalides appear in every modern inorganic chemistry textbook as an iconic chemical curiosity, yet their reactivity remains unexplored. This is due to their synthetic hurdles. In this work, we report the first facile synthesis of the archetypical alkalide complex, [Na+(2,2,2-cryptand)Na–], which allows us to unveil a versatile reactivity profile of this once exotic species.
KW - Mechanochemistry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608632
DO - https://doi.org/10.1021/acs.inorgchem.4c02914
VL - 63
IS - 32
SP - 15247
EP - 15258
PB - American Chemical Society (ACS)
AN - OPUS4-60863
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Klamrowski, Günter
A1 - Neustupny, Paul
A1 - Zajc, A.
ED - Sneck, T.
T1 - Degree of moisture saturation and mechanical properties of concrete
T2 - Third International Conference on the Durability of Building Materials and Components
CY - Espoo, Finland
DA - 12.08.1984
PY - 1984
SP - 500
EP - 509
CY - Espoo
AN - OPUS4-36800
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rosemann, Paul
A1 - Müller, Christina
A1 - Meyer, A.
A1 - Halle, T.
T1 - Influence of nitrogen on the corrosion resistance of martensitic stainless steels
N2 - The corrosion resistance of martensitic stainless steels (MSS) depends strongly on the chemical composition and the applied heat treatment. Both determines the distribution of the alloying elements in the microstructure and the resulting material properties. The addition of nitrogen is known to be beneficial for the pitting corrosion resistance of stainless steels. In case of MSS this effect is not only connected to nitrogen itself because nitrogen can be used to substitute carbon which also influences the result of the heat treatment process. This paper shows the effect of nitrogen on the corrosion resistance in relation to the hardening process of MSS. Therefore the effects of austenitization duration, austenitization temperature and cooling rate on microstructure, hardness and corrosion resistance were studied on the MSS X30CrMoN15 1 and X50CrMoV15. The effect of different cooling rates was studied in the range of > 100 K/s down to 1 K/s using the jominy end quench test. The changes in corrosion resistance were detected with electrochemical potentiodynamic reactivation (EPR) and by the determination of critical pitting potentials. Besides this experimental approach thermodynamic calculations with the software thermocalc will be presented and used for the interpretation of the effect of nitrogen on the corrosion resistance of MSS.
T2 - 18th Chemnitz Seminar on Materials Engineering – 18. Werkstofftechnisches Kolloquium
CY - Chemnitz, Germany
KW - Martensitic stainless steels
KW - Corrosion resistance
KW - Heat treatment
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366956
DO - https://doi.org/10.1088/1757-899X/118/1/011002
VL - 118
IS - 1
SP - 19
EP - 19
PB - IOP Publishing
AN - OPUS4-36695
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Heyn, A.
A1 - Rosemann, Paul
A1 - Babutzka, Martin
A1 - Bender, S.
T1 - Electrochemical noise of unalloyed steel in mixtures of water-based binders and pigments
N2 - The development of organic coatings for corrosion protection is an elaborate process with a multitude of often interminable investigations and tests of protection properties. Electrochemical methods support the processes of development to a great extent and help to understand mechanisms of action and failure. They are usually carried out on applied coating systems with a completed formulation. An examination possibility is presented in this publication that enables the characterization of waterbased coatings with different formulation variations in the liquid (aqueous) state with the aid of electrochemical noise technique. Thus, selection of binders, pigments, and other additives is supported essentially and made more efficient in a very early Phase of formulation development. The paper shows that a unique insight into the dynamic processes of a metal in contact with an aqueous coating dispersion is possible using the example of the development of zinc-free corrosion-inhibiting pigments for waterbased coatings. In addition, it is presented in which way the results correlate with the performance of applied coatings.
KW - Organic coatings
KW - Electrochemical noise
KW - Corrosion
KW - Corrosion protection
KW - Corrosion protection pigments
PY - 2017
DO - https://doi.org/10.1002/maco.201709671
SN - 0947-5117
SN - 1521-4176
VL - 68
IS - 12
SP - 1295
EP - 1301
PB - Wiley-VCH Verlag
CY - Weinheim
AN - OPUS4-43319
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -