TY - JOUR A1 - Mues genannt Koers, Lucas A1 - Prevost, David A1 - Paulßen, Elisabeth A1 - Hoehr, Cornelia T1 - Density reduction effects on the production of [11C]CO2 in Nb-body targets on a medical cyclotron N2 - Medical isotope production of 11C is commonly performed in gaseous targets. The power deposition of the proton beam during the irradiation decreases the target density due to thermodynamic mixing and can cause an increase of penetration depth and divergence of the proton beam. In order to investigate the difference how the target-body length influences the operation conditions and the production yield, a 12 cm and a 22 cm Nb-target body containing N2/O2 gas were irradiated using a 13 MeV proton cyclotron. It was found that the density reduction has a large influence on the pressure rise during irradiation and the achievable radioactive yield. The saturation activity of [11C]CO2 for the long target (0.083 Ci/μA) is about 10% higher than in the short target geometry (0.075 Ci/μA). Y1 - 2023 U6 - https://doi.org/10.1016/j.apradiso.2023.110911 VL - 199 IS - Art. 110911 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Mues genannt Koers, Lucas A1 - McNeil, S. W. A1 - Radchenko, V. A1 - Paulßen, Elisabeth A1 - Hoehr, Cornelia T1 - Production of Co-58m in a siphon-style liquid target on a medical cyclotron N2 - We present the production of 58mCo on a small, 13 MeV medical cyclotron utilizing a siphon style liquid target system. Different concentrated iron(III)-nitrate solutions of natural isotopic distribution were irradiated at varying initial pressures and subsequently separated by solid phase extraction chromatography. The radio cobalt (58m/gCo and 56Co) was successfully produced with saturation activities of (0.35 ± 0.03) MBq μA−1 for 58mCo with a separation recovery of (75 ± 2) % of cobalt after one separation step utilizing LN-resin. Y1 - 2023 U6 - https://doi.org/10.1016/j.apradiso.2023.110734 SN - 0969-8043 VL - 195 IS - Art. 110734 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Mueller, Tobias A1 - Segin, Alexander A1 - Weigand, Christoph A1 - Schmitt, Robert H. T1 - Feature selection for measurement models JF - International journal of quality & reliability management N2 - Purpose In the determination of the measurement uncertainty, the GUM procedure requires the building of a measurement model that establishes a functional relationship between the measurand and all influencing quantities. Since the effort of modelling as well as quantifying the measurement uncertainties depend on the number of influencing quantities considered, the aim of this study is to determine relevant influencing quantities and to remove irrelevant ones from the dataset. Design/methodology/approach In this work, it was investigated whether the effort of modelling for the determination of measurement uncertainty can be reduced by the use of feature selection (FS) methods. For this purpose, 9 different FS methods were tested on 16 artificial test datasets, whose properties (number of data points, number of features, complexity, features with low influence and redundant features) were varied via a design of experiments. Findings Based on a success metric, the stability, universality and complexity of the method, two FS methods could be identified that reliably identify relevant and irrelevant influencing quantities for a measurement model. Originality/value For the first time, FS methods were applied to datasets with properties of classical measurement processes. The simulation-based results serve as a basis for further research in the field of FS for measurement models. The identified algorithms will be applied to real measurement processes in the future. KW - Feature selection KW - Modelling KW - Measurement models KW - Measurement uncertainty Y1 - 2022 U6 - https://doi.org/10.1108/IJQRM-07-2021-0245 SN - 0265-671X IS - Vol. ahead-of-print, No. ahead-of-print. PB - Emerald Group Publishing Limited CY - Bingley ER - TY - JOUR A1 - Muck, A. A1 - Wang, J. A1 - Jacobs, M. A1 - Chen, G. A1 - Chatrathi, M. P. A1 - Jurka, V. A1 - Vyborny, Z. A1 - Spillmann, S. D. A1 - Sridharan, G. A1 - Schöning, Michael Josef T1 - Fabrication of poly(methyl methacrylate) microfluidic chips by atmospheric molding JF - Analytical Chemistry. 76 (2004), H. 8 Y1 - 2004 SN - 0003-2700 SP - 2290 EP - 2297 ER - TY - JOUR A1 - Mourzina, Yu.G. A1 - Schöning, Michael Josef A1 - Schubert, J. A1 - Zander, W. A1 - Legin, A. A1 - Vlasov, Y. G. A1 - Lüth, H. T1 - Thin film microsensors for fast heavy metal analysis JF - Proceedings : Copenhagen, Denmark, 27 - 30 August 2000 / [ed.: R. de Reus ...] Y1 - 2000 SN - 87-89935-50-0 N1 - Eurosensors ; (14, 2000, København) ; Eurosensors ; (14 : ; 2000.08.27-30 : ; Copenhagen) ; European Conference on Solid-State Transducers ; (14 : ; 2000.08.27-30 : ; Copenhagen) SP - 839 EP - 840 PB - MIC, Mikroelektronik Centret CY - Lyngby, Denmark ER - TY - JOUR A1 - Mourzina, Yu. G. A1 - Schubert, J A1 - Zander, W. A1 - Legin, A. A1 - Vlasov, Y. G. A1 - Lüth, H. A1 - Schöning, Michael Josef T1 - Development of multisensor systems based on chalcogenide thin film chemical sensors for the simultaneous multicomponent analysis of metal ions in complex solutions JF - Scaling down in electrochemistry : electrochemical micro- and nanosystem technology ; proceedings of the 3rd International Symposium on Electrochemical Microsystem Technologies, Garmisch-Patenkirchen, Germany, 11 - 15 September 2000 / ed. by J. W. Schultz Y1 - 2001 SN - 0-08-044014-2 SP - 251 EP - 263 PB - Elsevier [u.a.] CY - Amsterdam [u.a.] ER - TY - JOUR A1 - Mourzina, Y.G. A1 - Schöning, Michael Josef A1 - Schubert, J. A1 - Zander, W. A1 - Legin, A. V. A1 - Vlasov, Y. G. A1 - Kordos, P. A1 - Lüth, H. T1 - A new thin film Pb microsensor based on chalcogenide glasses JF - Sensors and Actuators B. 71 (2000), H. 1-2 Y1 - 2000 SN - 0925-4005 SP - 13 EP - 18 ER - TY - JOUR A1 - Mourzina, Y. A1 - Yoshinobu, T. A1 - Ermelenko, Y. A1 - Furuichi, K. A1 - Vlasov, Y. A1 - Schöning, Michael Josef A1 - Iwasaki, H. T1 - Technology of photocurable membranes for ion sensors based on laser scanned semiconductor transducer (LSST) JF - Book of abstracts / ed. by J. Saneistr. Y1 - 2002 SN - 80-01-02576-4 N1 - Eurosensors ; (16, 2002, Praha) SP - 254 EP - 257 PB - Czech Technical University, Faculty of Electrical Engineering, Department of Measurement CY - Prague ER - TY - JOUR A1 - Mourzina, Y. A1 - Mai, T. A1 - Poghossian, Arshak A1 - Ermolenko, Y. A1 - Yoshinobu, T. A1 - Vlasov, Y. A1 - Iwasaki, H. A1 - Schöning, Michael Josef T1 - K+-selective field-effect sensors as transducers for bioelectronic applications JF - Electrochimica Acta. 48 (2003), H. 20-22 Y1 - 2003 SN - 0013-4686 SP - 3333 EP - 3339 ER - TY - JOUR A1 - Mourzina, Y. G. A1 - Yoshinobu, T. A1 - Schubert, J. A1 - Lüth, H. A1 - Iwasaki, H. A1 - Schöning, Michael Josef T1 - Ion-selective lightaddressable potentiometric sensor (LAPS) with chalcogenide thin film by pulsed laser deposition JF - Sensors and Actuators B. 80 (2001), H. 2 Y1 - 2001 SN - 0925-4005 SP - 136 EP - 140 ER - TY - JOUR A1 - Mourzina, Y. G. A1 - Schöning, Michael Josef A1 - Schubert, J. A1 - Zander, W. A1 - Legin, A. V. A1 - Vlasov, Y. G. A1 - Lüth, H. T1 - Copper, cadmium and thallium thin film sensors based on chalcogenide glasses JF - Analytica Chimica Acta. 433 (2001) Y1 - 2001 SN - 0378-4304 SP - 103 EP - 110 ER - TY - JOUR A1 - Mourzina, Y. G. A1 - Legin, A. A1 - Vlasov, Y. G. A1 - Schöning, Michael Josef A1 - Schubert, J. A1 - Zander, W. A1 - Lüth, H. T1 - Thin film chemical sensors based on chalcogenide glasses for „electronic tongue“ applications JF - Sensor 2001 : 10th international conference, May 8 - 10, 2001, Exhibition Centre Nuremberg, Germany ; proceedings Y1 - 2001 N1 - Sensor-Kongress ; (10, 2001, Nürnberg) Sensor 2001 Conference ; (10 : ; 2001.05.08-10 : ; Nuremberg) SP - 137 EP - 141 PB - AMA Service CY - Wunstorf ER - TY - JOUR A1 - Mourzina, Y. G. A1 - Ermelenko, Y. E. A1 - Yoshinobu, T. A1 - Vlasov, Y. A1 - Iwasaki, H. A1 - Schöning, Michael Josef T1 - Anionselective light-addressable potentiometric sensors (LAPS) for the determination of nitrate and suphate ions JF - Sensors and Actuators B. 91 (2003), H. 1-3 Y1 - 2003 SN - 0925-4005 SP - 32 EP - 38 ER - TY - JOUR A1 - Mourzina, Ioulia G. A1 - Yoshinobu, Tatsuo A1 - Ermolenko, Yuri E. A1 - Vlasov, Yuri G. A1 - Schöning, Michael Josef A1 - Iwasaki, H. T1 - Immobilization of urease and cholinesterase on the surface of semiconductor transducer for the development of lightaddressable potentiometric sensors JF - Microchimica Acta. 144 (2004), H. 1-3 Y1 - 2004 SN - 0026-3672 SP - 41 EP - 50 ER - TY - JOUR A1 - Mourzina, I.G. A1 - Yoshinobu, T. A1 - Ermolenko, Y.E. A1 - Vlasov, Y. G. A1 - Schöning, Michael Josef A1 - Iwasaki, H. T1 - Immobilization of urease and cholinesterase on the surface of semiconductor transducer for the development of light-addressable potentiometric sensors JF - Technical digest of the 10th International Meeting on Chemical Sensors, July 11 - 14, 2004, Tsukuba, Japan / Japan Association of Chemical Sensors Y1 - 2004 N1 - Chemical sensors ; 20.2004 Suppl. B. IMCS ; (10, 2004, Tsukuba) ; International Meeting on Chemical Sensors ; (10 : ; 2004.07.11-14 : ; Tsukuba) SP - 788 EP - 789 PB - Japan Association of Chemical Sensors CY - Fukuoka ER - TY - JOUR A1 - Mottaghy, Darius A1 - Vosteen, Hans-Dieter A1 - Schellschmidt, Rüdiger T1 - Temperature dependence of the relationship of thermal diffusivity versus thermal conductivity for crystalline rocks JF - International Journal of Earth Sciences Y1 - 2008 U6 - https://doi.org/10.1007/s00531-007-0238-3 SN - 1437-3262 VL - 97 IS - 2 SP - 435 EP - 442 ER - TY - JOUR A1 - Mottaghy, Darius A1 - Schwamborn, G. A1 - Rath, V. T1 - Past climate changes and permafrost depth at the Lake El'gygytgyn site: implications from data and thermal modeling JF - Climate of the Past Y1 - 2013 U6 - https://doi.org/10.5194/cp-9-119-2013 SN - 1814-9332 VL - 9 IS - 1 SP - 119 EP - 133 PB - Copernicus CY - Katlenburg-Lindau ER - TY - JOUR A1 - Mottaghy, Darius A1 - Schellschmidt, R. A1 - Popov, Y. A. A1 - Clauser, C. A1 - Kukkonen, I. T. A1 - Nover, G. A1 - Milanovsky, S. A1 - Romushkevich, R. A. T1 - New heat flow data from the immediate vicinity of the Kola super-deep borehole: Vertical variation in heat flow density confirmed and attributed to advection JF - Tectonophysics Y1 - 2005 U6 - https://doi.org/10.1016/j.tecto.2005.03.005 SN - 1879-3266 VL - 401 IS - 1-2 SP - 119 EP - 142 ER - TY - JOUR A1 - Mottaghy, Darius A1 - Rath, Volker T1 - Latent heat effects in subsurface heat transport modelling and their impact on palaeotemperature reconstructions JF - Geophysical Journal International Y1 - 2006 U6 - https://doi.org/10.1111/j.1365-246X.2005.02843.x SN - 1365-246X VL - 164 IS - 1 SP - 236 EP - 245 ER - TY - JOUR A1 - Mottaghy, Darius A1 - Pechnig, Renate A1 - Vogt, Christian T1 - The geothermal project Den Haag: 3D numerical models for temperature prediction and reservoir simulation JF - Geothermics N2 - The proposed Den Haag Zuidwest district heating system of the city of The Hague consists of a deep doublet in a Jurassic sandstone layer that is designed for a production temperature of 75 °C and a reinjection temperature of 40 °C at a flow rate of 150 m3 h−1. The prediction of reservoir temperature and production behavior is crucial for success of the proposed geothermal doublet. This work presents the results of a study of the important geothermal and geohydrological issues for the doublet design. In the first phase of the study, the influences of the three-dimensional (3D) structures of anticlines and synclines on the temperature field were examined. A comprehensive petrophysical investigation was performed to build a large scale 3D-model of the reservoir. Several bottomhole temperatures (BHTs), as well as petrophysical logs were used to calibrate the model using thermal conductivity measurements on 50 samples from boreholes in different lithological units in the study area. Profiles and cross sections extracted from the calculated temperature field were used to study the temperature in the surrounding areas of the planned doublet. In the second phase of the project, a detailed 3D numerical reservoir model was set up, with the aim of predicting the evolution of the producer and injector temperatures, and the extent of the cooled area around the injector. The temperature model from the first phase provided the boundary conditions for the reservoir model. Hydraulic parameters for the target horizons, such as porosity and permeability, were taken from data available from the nearby exploration wells. The simulation results are encouraging as no significant thermal breakthrough is predicted. For the originally planned location of the producer, the extracted water temperature is predicted to be around 79 °C, with an almost negligible cooling in the first 50 years of production. When the producer is located shallower parts of the reservoir, the yield water temperatures is lower, starting at ≈76 °C and decreasing to ≈74 °C after 50 years of operation. This comparatively larger decrease in temperature with time is caused by the structural feature of the reservoir, namely a higher dip causes the cooler water to easily move downward. In view of the poor reservoir data, the reservoir simulation model is constructed to allow iterative updates using data assimilation during planned drilling, testing, and production phases. Measurements during an 8 h pumping test carried out in late 2010 suggest that a flow rate of 150 m3 h−1 is achievable. Fluid temperatures of 76.5 °C were measured, which is very close to the predicted value. Y1 - 2011 U6 - https://doi.org/10.1016/j.geothermics.2011.07.001 SN - 0375-6505 VL - 40 IS - 3 SP - 199 EP - 210 PB - Elsevier CY - Amsterdam ER -