TY - JOUR A1 - Engelmann, Ulrich M. A1 - Simsek, Beril A1 - Shalaby, Ahmed A1 - Krause, Hans-Joachim T1 - Key contributors to signal generation in frequency mixing magnetic detection (FMMD): an in silico study JF - Sensors N2 - Frequency mixing magnetic detection (FMMD) is a sensitive and selective technique to detect magnetic nanoparticles (MNPs) serving as probes for binding biological targets. Its principle relies on the nonlinear magnetic relaxation dynamics of a particle ensemble interacting with a dual frequency external magnetic field. In order to increase its sensitivity, lower its limit of detection and overall improve its applicability in biosensing, matching combinations of external field parameters and internal particle properties are being sought to advance FMMD. In this study, we systematically probe the aforementioned interaction with coupled Néel–Brownian dynamic relaxation simulations to examine how key MNP properties as well as applied field parameters affect the frequency mixing signal generation. It is found that the core size of MNPs dominates their nonlinear magnetic response, with the strongest contributions from the largest particles. The drive field amplitude dominates the shape of the field-dependent response, whereas effective anisotropy and hydrodynamic size of the particles only weakly influence the signal generation in FMMD. For tailoring the MNP properties and parameters of the setup towards optimal FMMD signal generation, our findings suggest choosing large particles of core sizes dc > 25 nm nm with narrow size distributions (σ < 0.1) to minimize the required drive field amplitude. This allows potential improvements of FMMD as a stand-alone application, as well as advances in magnetic particle imaging, hyperthermia and magnetic immunoassays. KW - key performance indicators KW - magnetic biosensing KW - coupled Néel–Brownian relaxation dynamics KW - frequency mixing magnetic detection KW - magnetic relaxation KW - micromagnetic simulation KW - magnetic nanoparticles Y1 - 2024 U6 - https://doi.org/10.3390/s24061945 SN - 1424-8220 N1 - This article belongs to the Special Issue "Advances in Magnetic Sensors and Their Applications" VL - 24 IS - 6 PB - MDPI CY - Basel ER - TY - JOUR A1 - Horbach, Andreas A1 - Staat, Manfred T1 - Optical strain measurement for the modeling of surgical meshes and their porosity JF - Current Directions in Biomedical Engineering N2 - The porosity of surgical meshes makes them flexible for large elastic deformation and establishes the healing conditions of good tissue in growth. The biomechanic modeling of orthotropic and compressible materials requires new materials models and simulstaneoaus fit of deformation in the load direction as well as trannsversely to to load. This nonlinear modeling can be achieved by an optical deformation measurement. At the same time the full field deformation measurement allows the dermination of the change of porosity with deformation. Also the socalled effective porosity, which has been defined to asses the tisssue interatcion with the mesh implants, can be determined from the global deformation of the surgical meshes. Y1 - 2018 U6 - https://doi.org/10.1515/cdbme-2018-0045 SN - 2364-5504 VL - Band 4 IS - 1 SP - 181 EP - 184 PB - De Gruyter CY - Berlin ER - TY - CHAP A1 - Ernhardt, Selina A1 - Drumm, Christian A1 - van Gog, Tamara A1 - Brand-Gruwel, Saskia A1 - Jarodzka, Halszka T1 - Through the eyes of a programmer : a research project on how to foster programming education with eye-tracking technology T2 - Tagungsband zur 32. AKWI-Jahrestagung vom 15.09.2019 bis 18.09.2019 an der Fachhochschule für Angewandte Wissenschaften Aachen Y1 - 2019 SN - 978-3-944330-62-4 SP - 42 EP - 47 PB - Mana-Buch CY - Heide ER - TY - JOUR A1 - Baringhaus, Ludwig A1 - Gaigall, Daniel T1 - Hotelling’s T² tests in paired and independent survey samples: An efficiency comparison JF - Journal of Multivariate Analysis N2 - Hotelling’s T² tests in paired and independent survey samples are compared using the traditional asymptotic efficiency concepts of Hodges–Lehmann, Bahadur and Pitman, as well as through criteria based on the volumes of corresponding confidence regions. Conditions characterizing the superiority of a procedure are given in terms of population canonical correlation type coefficients. Statistical tests for checking these conditions are developed. Test statistics based on the eigenvalues of a symmetrized sample cross-covariance matrix are suggested, as well as test statistics based on sample canonical correlation type coefficients. Y1 - 2017 U6 - https://doi.org/10.1016/j.jmva.2016.11.004 SN - 0047-259X VL - 2017 IS - 154 SP - 177 EP - 198 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wang, Mao A1 - Anik, Sabri A1 - Frohberg, Martin G. T1 - Thermodynamics of oxygen in the lead-antimony system at 1173 K JF - Erzmetall : Rohstoffgewinnung, Verarbeitung, Recycling, Umwelttechnik Y1 - 1987 SN - 0044-2658 VL - 40 IS - 6 SP - 316 EP - 319 ER - TY - JOUR A1 - Herrmann, Ulf A1 - Kearney, David W. T1 - Survey of Thermal Energy Storage for Parabolic Trough Power Plants JF - Journal of Solar Energy Engineering Y1 - 2002 U6 - https://doi.org/10.1115/1.1467601 SN - 1528-8986 (Online) SN - 0199-6231 (Print) VL - 124 IS - 2 SP - 145 EP - 152 ER - TY - GEN A1 - Roth, J. A1 - Tippkötter, Nils T1 - New Approach for Enzymatic Hydrolysis of Lignocellulose with Selective Diffusion Separation of the Monosaccharide Products T2 - Chemie Ingenieur Technik N2 - Enzymatic hydrolysis of lignocellulosic material plays an important role in the classical biorefinery approach. Apart from the pretreatment of the raw material, hydrolysis is the basis for the conversion of the cellulose and hemicellulose fraction into fermentable sugars. After hydrolysis, usually a solid-liquid separation takes place, in order to separate the residual plant material from the sugar-rich fraction, which can be subsequently used in a fermentation step. In order to factor out the separation step, the usage of in alginate immobilized crude cellulose fiber beads (CFBs) were evaluated. Pretreated cellulose fibers are incorporated in an alginate matrix together with the relevant enzymes. In doing so, sugars diffuse trough the alginate matrix, allowing a simplified delivery into the surrounding fluid. This again reduces product inhibition of the glucose on the enzyme catalysts. By means of standardized bead production the hydrolysis in lab scale was possible. First results show that liberation of glucose and xylose is possible, allowing a maximum total sugar yield of 75 %. Y1 - 2016 U6 - https://doi.org/10.1002/cite.201650301 SN - 0009-286X SN - 1522-2640 (eISSN) N1 - ProcessNet-Jahrestagung 2016 und 32. DECHEMA-Jahrestagung der Biotechnologen 2016, 12. - 15. September 2016, Eurogress Aachen VL - 88 IS - 9 SP - 1237 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Lévesque, Mathieu A1 - Siegwolf, Rolf A1 - Eilmann, Britta A1 - Saurer, Matthias A1 - Rigling, Andreas T1 - Increased water-use efficiency does not lead to enhanced tree growth under xeric and mesic conditions JF - New Phytologist Y1 - 2014 U6 - https://doi.org/10.1111/nph.12772 SN - 1469-8137 (Online) SN - 0028-646X (Print) VL - 203 IS - 1 SP - 94 EP - 109 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Kearney, David W. A1 - Kelly, Bruce A1 - Herrmann, Ulf A1 - Cable, R. A1 - Pacheco, J. A1 - Mahoney, R. A1 - Price, Henry A1 - Blake, D. A1 - Nava, P. A1 - Potrovitza, N. T1 - Engineering Aspects of a Molten Salt Heat Transfer Fluid in a Trough Solar Field JF - Energy : the international journal Y1 - 2002 U6 - https://doi.org/10.1016/S0360-5442(03)00191-9 SN - 0360-5442 N1 - SolarPACES 2002, Zürich, Switzerland, 4–6 September 2002 VL - 29 IS - 5-6 (Special Issue SolarPaces) SP - 861 EP - 870 ER - TY - JOUR A1 - Frohberg, Martin G. A1 - Anik, Sabri T1 - Thermodynamic relations between component activities and gas solubilities in binary metallic systems JF - Berichte der Bunsengesellschaft für physikalische Chemie Y1 - 1985 SN - 0940-483X SN - 0005-9021 VL - 89 IS - 2 SP - 130 EP - 134 ER -