TY - CONF A1 - Tiebe, Carlo A1 - Detjens, Marc A1 - Fechner, A. A1 - Sielemann, S. A1 - Lorek, A. A1 - Wernecke, R. A1 - Stoltenberg, H. T1 - Development of a device for staged determination of water activity and moisture content N2 - Moisture content and water activity are important parameters for quality characterization of products like bulk materials, powders, granules. Thus, an exact determination is necessarily required in a wide range of industrial applications. Moisture of materials is the content of non-chemically bound water in a solid or liquid. Water activity (aW) is a characteristic/parameter of the non-chemically bound ("free") water in materials and is measured as humidity over a solid/liquid surface at constant temperature (equilibrium moisture content). It is an important parameter to characterize the quality of e. g. pharmaceutical and food products. In our contribution, we present the developed MOISHUM device for staged determination of water activity and moisture content of liquid and solid materials. T2 - Eurosensors 2018 CY - Graz, Austria DA - 09.09.2018 KW - Water activity KW - Moisture KW - Coulometric humidity sensor KW - MOISHUM PY - 2018 SN - 2504-3900 SP - 7253, 1 EP - 4 PB - MDPI AN - OPUS4-46210 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Johann, Sergej A1 - Bartholmai, Matthias A1 - Neumann, Patrick P. A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Bartelmeß, Jürgen T1 - Adaptable multi-sensor device for gas detection N2 - Innovation is the catalyst for the technology of the future. It is important to develop new and better technologies that can continuously monitor the environmental impact, e.g., for air quality control or emission detection. In the recently at BAM developed Universal Pump Sensor Control (UPSC3) module, different components and sensors are fused. The combination of the individual components makes the UPSC3 module an excellent monitoring and reference system for the development and characterization of gas specific sensors. Measurements over long periods are possible, for mixed gas loads or for certain gas measurements. The system is part of a mobile sensor network of several sensor units, which can also be used as standalone systems. The motivation and objective of this research is to develop gas sensors based on fluorescence detection with range of ppm / ppb. For this task a reference system is required, which contains volatile organic compound (VOC) sensors for reference data from different scenarios. The integrated multi-sensor unit can measure different gases through the integrated 3-fold VOC sensor, which can be adapted to the addressed scenario. . The system-integrated flow control, with pump and flow sensor, allows the gas molecules to be transported directly to the VOC sensor. The entire measurement is permanently stored on an integrated memory card. If the previously determined limit range is exceeded, an alarm is generated. The system is an important tool towards further developments in the field of gas sensors and is primarily used for the validation of chemically based gas sensors. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas detection KW - Multi sensor device KW - Pump control KW - VOC PY - 2017 AN - OPUS4-43193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Theiler, Geraldine A1 - Gradt, Thomas T1 - Tribological characteristics of polyimide composites in hydrogen environment N2 - The influence of hydrogen environment on the friction and wear behavior of polyimide (PI) composites was investigated for two different PI-types (PI1 and PI2) filled with natural or synthetic graphite. Sliding tests were run against AISI 52100 steel and the worn surfaces as well as the transfer film were analyzed by means of SEM, EDX and Infrared Spectroscopy. Results indicate that the chemical structure of the polyimide has a major influence on the tribological behavior. While the friction of PI2 remains rather stable in all environments, PI1 showed very low friction in hydrogen without any lubricant. The lubricity of graphite was found to be more effective in hydrogen than in moist air. KW - Sliding friction KW - Polyimide KW - Graphite KW - Hydrogen PY - 2015 DO - https://doi.org/10.1016/j.triboint.2015.06.001 SN - 0301-679X VL - 92 SP - 162 EP - 171 PB - Elsevier Ltd. CY - Oxford AN - OPUS4-33555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Detjens, Marc A1 - Tiebe, Carlo A1 - Banach, Ulrich A1 - Ritter, U. T1 - Ionische Flüssigkeiten als neuartige Sensorbeschichtung für coulometrische Spurenfeuchtesensoren N2 - Die Arbeit präsentiert erste Messungen mit coulometrischen Sensoren, die mit einer ionischen Flüssigkeit beschichtet sind. Diese Sensoren werden in der Industrie verwendet, um die Spurenfeuchte in unterschiedlichen Gasen zu messen. Normalerweise erfolgt eine Beschichtung der Sensoren mit Phosphorpentoxid und dessen Hydrolyseprodukte. In dieser Arbeit wurde stattdessen eine hygroskopische ionische Flüssigkeit benutzt. Die generierte Gasfeuchte für die Untersuchungen betrug bezogen auf die Frostpunkttemperatur -80 °C bis -30 °C, was gleichbedeutend mit einem Wasserdampf-Stoffmengenanteil von 0,5 μmol·mol-1 bis 376 μmol·mol-1 ist. Zusätzlich zu der Messung mit coulometrischen Sensoren erfolgte eine Referenzmessung der Gasfeuchte mittels eines Taupunkthygrometers. Erste Ergebnisse haben gezeigt, dass es möglich ist mit dieser Art der Beschichtung unterschiedliche Gasfeuchten zu messen. Aber es ergaben sich trotz gleicher Feuchte unterschiedliche Signalintensitäten bei den benutzen Sensoren und es zeigte sich eine Drift des Sensorsignales. T2 - Sensoren und Messsysteme CY - Nuremberg, Germany DA - 26.06.2018 KW - Spurenfeuchtemessung KW - Sensorbeschichtung KW - Elektrolyseverfahren KW - Ionische Flüssigkeiten PY - 2018 SN - 978-3-8007-4683-5 SN - 0932-6022 SP - 520 EP - 523 PB - VDE VERLAG GMBH CY - Berlin, Offenbach AN - OPUS4-45319 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Moufid, M. A1 - Tiebe, Carlo A1 - El Bari, N. A1 - Bartholmai, Matthias A1 - Bouchikhi, B. T1 - Combining of TD-GC-MS and home developed electronic nose for road traffic air monitoring N2 - In this work, we demonstrate the ability of an electronic nose system based on an array of six-semiconductor gas sensors for outdoor air quality monitoring over a day at a traffic road in downtown of Meknes city (Morocco). The response of the sensor array reaches its maximum in the evening of the investigated day which may due to high vehicular traffic or/and human habits resulting in elevated concentrations of pollutants. Dataset treatment by Principal Component Analysis and Discriminant Function Analysis shows a good discrimination between samples collected at different times of the day. Moreover, Support Vector Machines were used and reached a classification success rate of 97.5 %. Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC-MS) technique was used to validate the developed e-nose system by identifying the composition of the analyzed air samples. The discrimination obtained by e-nose system was in good agreement with the TD-GC-MS results. This study demonstrates the usefulness of TD-GC-MS and e-nose, providing high accuracy in discriminating outdoor air samples collected at different times. This demonstrates the potential of using the e-nose as a rapid, easy to use and inexpensive environmental monitoring system. T2 - 2021 IEEE International Conference on Design & Test of Integrated Micro & Nano-Systems (DTS) CY - Sfax, Tunisia DA - 07.06.2021 KW - GC-MS KW - Electronic nose KW - Gas sensors KW - Urban air monitoring PY - 2021 DO - https://doi.org/10.1109/DTS52014.2021.9498110 SP - 1 EP - 6 AN - OPUS4-54401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Johann, Sergej A1 - Baensch, Franziska A1 - Sturm, Patrick A1 - Tiebe, Carlo A1 - Pötschke, Samuel A1 - Lay, Vera ED - Holl, H. T1 - HF RFID-based measurement comparison for method optimization in M2 concrete and alkali-activated mortars N2 - Monitoring of repositories for radioactive waste requires techniques which can be applied long-term under harsh conditions. In this work, the reliability and suitability of materials and a capacitive sensor for measuring relative humidity are investigated, which are to be embedded in the special concrete components for the closure structures of underground repository. Preliminary tests with accelerated aging of the materials used, validation of the sensors under difficult conditions, investigations of the surfaces after aging by pH 14 solution, defined exposure of the sensors in a climatic chamber and the microscope images are discussed. The results will be used for further development and optimization of the RFID based sensor systems which can be applied to monitor the condition of different building structures without cabling. T2 - 37th Danubia - Adria Symposium on Advances in Experimental Mechanics CY - Linz, Austria DA - 21.09.2021 KW - Alkali-activated mortars KW - Passive sensor interface KW - RFID KW - Structural health monitoring KW - Smart structures PY - 2022 DO - https://doi.org/10.1016/j.matpr.2022.03.465 SN - 2214-7853 VL - 62 IS - 5 SP - 2571 EP - 2576 PB - Elsevier CY - Amsterdam AN - OPUS4-54697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sarif, Raduan A1 - Tiebe, Carlo A1 - Herglotz, Christian T1 - Early Response Prediction for H2 Sensors N2 - Green hydrogen (H2) is essential for the global transition to clean energy; it will significantly reduce emissions from heavy industry and the long-distance transport system. H2 can be used as fuel in fuel cells, storing surplus renewable energy, and as a feedstock in industrial processes. However, H2 faces significant safety challenges during storage and transportation. Accidents due to H2 leakage and explosions raise serious concerns due to its high flammability, rapid diffusion in air, and extremely low ignition energy. To mitigate risks associated with H2 leakages, reliable and automated H2 safety systems are essential for emergency repairs or shutdown. An early response from H2 sensors is crucial for early warning in accidents. The earlier response time of H2 sensors is often constrained by their sensor principle, which is heavily influenced by the sensor material’s properties. This study explores methods for earlier sensor response through predictive algorithms. Specifically, we investigate transient response predictions using a First-Order (FO) model and propose improvements through the First-Order with early response and the First-Order with adapted early response model. Both models can predict the stable value of the H2 sensor response from a small time window, which is 70.89% and 83.72% earlier, respectively, than the time required for the sensor hardware to reach it physically. The model’s performance is evaluated by calculating the fitting error with a 2 % threshold. Our current research lays the groundwork for future advancements in real-time sensor response predictions for hydrogen leakage. T2 - IARIA Congress 2025 : The 2025 IARIA Annual Congress on Frontiers in Science, Technology, Services, and Applications CY - Venice, Italy DA - 06.07.2025 KW - H2 Safety KW - H2 leakage detection KW - First-Order (FO) model KW - H2 Sensor data analysis KW - H2 sensor response predictions PY - 2025 AN - OPUS4-64195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberwein, Robert T1 - Repeatable Testing of a Cryogenic Storage Tank with Variable Insulation Material in Fire Like Conditions N2 - For decarbonizing the energy industry and transport, cryogenic energy carriers have great potential. The storage takes place in tanks with thermal super-insulations, which are in application for decades, but there is only limited knowledge about its behaviour in a fire scenario. This represents a major incident that may generate extraordinary loads on the tank and its insulation system, and that eventually lead to a sudden tank failure. This paper presents a test rig called the Cryogenic High Temperature Thermal Vacuum Chamber (CHTTVC), which can be used to test typical thermal superinsulation’s under cryogenic and fire-like conditions in parallel. The test method makes it possible to measure the heat flow through the thermal superinsulation over time and to investigate the degradation behaviour of the insulation within a test. In the paper results from the first tests are presented. T2 - 18th Cryogenics 2025, IIR Conference CY - Prague, Czech Republic DA - 07.04.2025 KW - LH2 KW - LNG KW - Fire KW - Insulation PY - 2025 AN - OPUS4-62979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Prewitz, M. A1 - Gaber, M. A1 - Müller, Ralf A1 - Marotzke, C. A1 - Holtappels, Kai T1 - Polymer coated glass capillaries and structures for high-pressure hydrogen storage: Permeability and hydrogen tightness N2 - The hydrogen tightness of high-pressure hydrogen storage is a Basic criterion for long-term storage. The H2 permeation coefficients of epoxy resin and a glass lacquer were determined to enable the geometric optimization of a glass capillary storage. It was found that the curing conditions have no significant influence on the H2 permeation coefficient of resin. The H2 permeation coefficient of epoxy resin is only about three orders of Magnitude greater than that of borosilicate glass. This suggests that the initial pressure of 700 bar takes about 2.5 years to be halved in capillary array storage. Therefore, a high-pressure hydrogen storage tank based on glass capillaries is ideally suited for long-term storage in mobile applications. KW - Permeability KW - Glass capillaries KW - Coating KW - Hydrogen storage KW - Long-term calculation KW - Epoxy resin PY - 2018 DO - https://doi.org/10.1016/j.ijhydene.2017.12.092 SN - 0360-3199 VL - 43 IS - 11 SP - 5637 EP - 5644 PB - Elsevier AN - OPUS4-44327 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holtappels, Kai T1 - Trust in Hydrogen Technologies - Safety Issues in the Hydrogen Value Chain N2 - In June 2020, updated in July 2023, the German government presented the National Hydrogen Strategy (NHS), its first strategy for achieving the goals of its hydrogen policy. The NHS sets out a coherent framework for action for the future production, transportation and use of hydrogen and its derivatives, including the corresponding research, innovations and investments. Various measures have been defined to achieve goals such as the decarbonization of various sectors and the market introduction of hydrogen technologies. This will ultimately lead to the introduction of many “new” technologies in many areas of our daily lives, which will only be successful if decision-makers and the public are convinced that these technologies are safe. Therefore, the safety of hydrogen technologies is an important pillar in gaining and maintaining confidence in these new technologies. Safety must keep pace with, or better still anticipate, trends in technological development in order to avoid overly conservative and expensive s T2 - 10th World Energy Congress (WEC 2024) CY - Singapore DA - 12.11.2024 KW - Hydrogen Safety KW - Trustworthiness KW - Safety research KW - Accidents PY - 2024 AN - OPUS4-62174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Melzer, Michael A1 - Nattuveettil, Keerthana T1 - Automated generation and utilization of accredited temperature DCCs N2 - The accredited calibration laboratory of the German Federal Institute for Materials Research and Testing (BAM) has established verified XML digital calibration certificates for calibrations of resistance thermometers within the scope of its accreditation. Hence, all necessary information according to ISO/IEC 17025 and the DKD-R 5-1 calibration rule is provided in a machine-readable and machine-interpretable form. For the automated DCC generation, a self-implemented middleware is compiling the metadata (i.e. customer-, order-, item- and method data) and combines it with the measured calibration data and influence conditions into a process- and lab-specific DCC template. This DCC software is able to handle both, single probe calibrations (e.g. Pt 100) as well as measurement chains (e.g. thermometers and temperature loggers) and also supports multiple item calibrations with the automated creation of individual DCC files. All generated DCCs can be readily validated against the DCC scheme (v.3.2.1). The validated and authorized DCCs are equipped with the novel digital accreditation symbol, that was recently piloted with the German national accreditation body (DAkkS), to form `eAttestations´. This advanced electronic seal with a qualified certificate, after successful validation by the receiver, provides three basic functionalities in a DCC: 1. Authenticity: It confirms that the issued certificate actually originates from the BAM calibration laboratory (D-K-11075-08) 2. Integrity: It protects all the data and information in the DCC from change and manipulation 3. Accreditation: It verifies the active accreditation status of the issuing body at the time of sealing (authorization) Thus, this accreditation seal can fully replace an electronic signature on an accredited DCC. In order to demonstrate the added value of DCCs also on the receiver side, the BAM DCC-team started to develop a simple but capable DCC demonstrator. For the use case of thermal process monitoring, the software reads out the metrological data of an incoming DCC, performs a linear regression of the temperature calibration values, uses the obtained calibration function to correct the raw sensor readings, extends the DCC measurement uncertainty values with further contributions (e.g. from the correction and the hysteresis) and adjusts the process-defined acceptance limits to account for the measurement uncertainty, all in real-time. Hence, it automatically utilizes a DCC to obtain metrological traceability and a quality-assured process conformity assessment, practically at the push of a button. In the talk, the automated DCC generation in the scope of our accreditation, including the electronic sealing with the digital accreditation symbol, as well as the one-click DCC utilization with our demonstrator will be presented. The work was performed within the national QI-Digital initiative. T2 - 4th International DCC Conference CY - Online meeting DA - 27.02.2024 KW - Digital Calibration Certificate KW - DCC KW - E-Attestation KW - Calibration KW - Digital Metrology PY - 2024 UR - https://www.dcc-conference-2024.ptb.de/home N1 - Video file from minute 28 on AN - OPUS4-61867 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine A1 - Halder, Karabi A1 - Balasooriya, Winoj T1 - Effect of high-pressure hydrogen environment on the physical and mechanical properties of elastomers N2 - This paper deals with the exposure of HBNR rubbers to high pressure hydrogen (100 MPa) at 120 °C for 7 and 21 days under static conditions followed by characterization of their physical and mechanical properties. T2 - EHEC European Hydrogen Energy Conference 2022 CY - Madrid, Spain DA - 18.05.2022 KW - Rubbers KW - Hydrogen KW - Characterization PY - 2022 SP - 1 EP - 2 AN - OPUS4-62085 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Harwege, Finn T1 - Testing of vacuum insulation panels for liquefied hydrogen storage tanks N2 - For the future use of liquefied hydrogen (LH2) as a green energy carrier, new concepts for storage tanks and in particular their insulation are necessary. The methodology applied in current LH2 tanks has some disadvantages while manufacturing and operation of large tanks that may be required in the future. While liquefied natural gas tanks exist in the necessary capacities, they are incompatible with LH2 due to its significantly lower storage temperature. In this paper, the possibility of using vacuum insulation panels (VIPs) as an alternative to the conventional double walled, powder filled vacuum insulation is presented. The two systems are introduced and compared on a conceptual level with a focus on the loss of vacuum failure mode. Furthermore, a test rig that enables the testing and quantification of thermal properties of VIP based insulations in ordinary and loss of vacuum conditions is presented. The test rig is a boil-off calorimeter using liquefied nitrogen and features a square cold surface with a side length of 2 m. An overview over the planned testing and its goals is given. T2 - 18th International Symposium on Loss Prevention and Safety Promotion in the Process Industries CY - Bologna, Italy DA - 08.06.2025 KW - Liquefied Hydrogen KW - LH2 KW - Cryogenics KW - Vacuum KW - Vacuum Insulation Panel PY - 2025 AN - OPUS4-63426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -