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Further development of a Lamb-shift polarimeter
No full textThe Lamb-shift polarimeter (LSP) is a useful detection apparatus to verify nuclear spin polarizationfor atoms, molecules and ions consisting of hydrogen and/or its isotopes. Its functionality relieson the creation of metastable hydrogen atoms via a charge exchange reaction that preserves thenuclear polarization in a strong magnetic field. The nuclear polarization is then determinedby analyzing the relative occupation numbers between different metastable hyperfine states withdifferent nuclear spin projection . This makes the LSP a very rapid and cost efficient detectionmethod for beams with a beam energy in the keV range as no pre-acceleration is needed. In thepast it was shown that many of the above mentioned candidates like , , etc. could bemeasured with success, and in this work an additional ion, i.e. , adds up to the list. Furthermore,the measurements of polarized ions have been performed for pulsed beams as it was in usefor long times at the cooler synchrotron COSY in Jülich. In the second part, a theoretical outlookfor possible adaptations to the spin filter is given, which is an important component of the LSP.This paves the way to realize experiments investigating the bound beta decay or parity violation inmetastable hydrogen atoms. In addition, a short outlook for possible applications of beamsis given
Dynamic Analysis of the Effect of the Device-to-Device Variability of Real-World Memristors on the Implementation of Uncoupled Memristive Cellular Nonlinear Networks
No full textCoherent and non-unitary errors in ZZ-generated gates
No full textVariational algorithms such as the quantum approximate optimization algorithm have attracted attention due to their potential for solving problems using near-term quantum computers. The ZZ interaction typically generates the primitive two-qubit gate in such algorithms applied for a time, typically a variational parameter, γ. Different compilation techniques exist with respect to the implementation of two-qubit gates. Due to the importance of the ZZ-gate, we present an error analysis comparing the continuous-angle controlled phase gate (CP) against the fixed angle controlled Z-gate (CZ). We analyze both techniques under the influence of coherent over-rotation and depolarizing noise. We show that CP and CZ compilation techniques achieve comparable ZZ-gate fidelities if the incoherent error is below 0.03% and the coherent error is below 0.8%. Thus, we argue that for small coherent and incoherent error a non-parameterized two-qubit gate such as CZ in combination with virtual Z decomposition for single-qubit gates could lead to a significant reduction in the calibration required and, therefore, a less error-prone quantum device. We show that above a coherent error of 0.04π (2%), the CZ gate fidelity depends significantly on γ
A Rhizobox-Study Elucidating Biogas-Digestate Fertilization and Soil Compaction Effects on Juvenile Maize Growth and Rhizosphere pH
No full textBiogas digestate (BD) contains nitrogen (N), phosphorus (P), and potassium (K) and is easily and largely available in Germany and other countries in Europe. Nevertheless, few studies compare BD to mineral NPK fertilizer, particularly under soil compaction. The characteristics of these fertilizers and soil compaction may affect rhizosphere pH and root development, thereby affecting nutrient uptake by plants. This 18-day rhizobox study evaluated initial maize growth and root architecture responses to BD (derived from maize silage+chicken manure), mineral NPK, and BD + NPK fertilization under compacted (0–25 cm compacted; 25–55 cm loose) and loose (0–55 cm) substrates. Treatments promoted similar shoot biomass, specific leaf area, and sufficient shoot N, P, and K nutrition. Shoot P content in BD + NPK and NPK was 29–33% higher compared to BD. Root P content in NPK was 26% higher than in BD, independent of compaction, likely favoring root proliferation and explaining the higher root:shoot ratio in NPK. In loose soil, the main root length in NPK was 49% higher compared to BD, but rooting was deeper in BD. Rhizosphere alkalinization measured non-invasively suggested preferential maize N absorption as nitrate. Combining BD with fast-soluble P sources may provide maize performance comparable to mineral NPK
Understanding SOEC Performance and Degradation:A Multiphysics Approach for Experiment-driven Finite-Element-Modeling
No full textThis talk, given at the IET-1 Spring Seminar 2025, discusses a multiphysics approach to modeling Solid Oxide Electrolysis Cells (SOECs), focusing on integrating experimental data with simulation results to better understand performance and degradation mechanisms. A brief overview over the used model is provided and the results of the model's benchmarking and optimization procedure are communicated and discussed. Results highlight the potential for accurately modeling SOEC behavior and but also show potential for further refinement to extedn the model into a platform to predict performance and guide material development
A Next Generation RF LINAC as Proton Driver For CANS
No full textThe use of neutrons is established since decades and essential for industry, medicine, life sciencesand research. Classical neutron sources are mainly neutron generators, with low neutron flux, orresearch reactors and spallation sources, which are large and cost intensive installations. A costefficient, effective and compact neutron source could bridge the gap existing and offer potentialusers either a dedicated standalone version for high demands of a single application or a full variableuser facility. Such a compact accelerator driven neutron source based on a radio frequency linearaccelerator (linac) accelerating 10 - 20 mA of proton current to energies between 8 to 10 MeV candeliver neutron fluxes between 109 –1013 n/cm2/s.A concept for a reliable proton linear accelerator using a combination of high duty cycle H-modecavities that can be cooled well and 4-rod RFQs suitable for cw operation presents a cost efficient,reliable and well proven linac design for such applications. The neutron target is based on diffusionbonded beryllium as the most suitable choice to be operated for such a neutron source. The linacwill have about 15 m in total length including the target station and can be installed and operatedfor reasonable costs. We will present the current status of such an accelerator-based neutron sourceand potential perspectives
Automatisierte Konstruktion einer Sekretionsstammbibliothek für die Produktion von Adhäsionsvermittlern zur Mikroplastikdetektion
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