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61.
Ivona Kafedjiska Igal Levine Artem Musiienko Natalia Maticiuc Tobias Bertram Amran Al-Ashouri Christian A. Kaufmann Steve Albrecht Rutger Schlatmann Iver Lauermann 《Advanced functional materials》2023,33(34):2302924
The performance of five hole-transporting layers (HTLs) is investigated in both single-junction perovskite and Cu(In, Ga)Se2 (CIGSe)-perovskite tandem solar cells: nickel oxide (NiOx,), copper-doped nickel oxide (NiOx:Cu), NiOx+SAM, NiOx:Cu+SAM, and SAM, where SAM is the [2-(3,-6Dimethoxy-9H-carbazol-9yl)ethyl]phosphonic acid (MeO-2PACz) self-assembled monolayer. The performance of the devices is correlated to the charge-carrier dynamics at the HTL/perovskite interface and the limiting factors of these HTLs are analyzed by performing time-resolved and absolute photoluminescence ((Tr)PL), transient surface photovoltage (tr-SPV), and X-ray/UV photoemission spectroscopy (XPS/UPS) measurements on indium tin oxide (ITO)/HTL/perovskite and CIGSe/HTL/perovskite stacks. A high quasi-Fermi level splitting to open-circuit (QFLS-Voc) deficit is detected for the NiOx-based devices, attributed to electron trapping and poor hole extraction at the NiOx-perovskite interface and a low carrier effective lifetime in the bulk of the perovskite. Simultaneously, doping the NiOx with 2% Cu and passivating its surface with MeO-2PACz suppresses the electron trapping, enhances the holes extraction, reduces the non-radiative interfacial recombination, and improves the band alignment. Due to this superior interfacial charge-carrier dynamics, NiOx:Cu+SAM is found to be the most suitable HTL for the monolithic CIGSe-perovskite tandem devices, enabling a power-conversion efficiency (PCE) of 23.4%, Voc of 1.72V, and a fill factor (FF) of 71%, while the remaining four HTLs suffer from prominent Voc and FF losses. 相似文献
62.
Noei Maziar Luckner Paul Linn Tobias Jungemann Christoph 《Journal of Computational Electronics》2022,21(1):153-168
Journal of Computational Electronics - We discuss the numerical aspects of the Boltzmann transport equation (BE) for electrons in semiconductor devices, which is stabilized by Godunov’s... 相似文献
63.
Journal of Intelligent Manufacturing - Deep learning-based predictive quality enables manufacturing companies to make data-driven predictions of the quality of a produced product based on process... 相似文献
64.
Georg Menge Hannes Lorenz Zongwen Fu Franziska Eichhorn Florian Schader Kyle G. Webber Tobias Fey Peter Greil Nahum Travitzky 《Advanced Engineering Materials》2018,20(7)
65.
Jan Tobias Krüger Kay-Peter Hoyer Anatolii Andreiev Mirko Schaper Carolin Zinn 《Advanced Engineering Materials》2023,25(3):2201008
In medical technology, implants are used to improve the quality of patients’ lives. The development of materials with adapted properties can further increase the benefit of implants. If implants are only needed temporarily, biodegradable materials are beneficial. In this context, iron-based materials are promising due to their biocompatibility and mechanical properties, but the degradation rate needs to be accelerated. Apart from alloying, the creation of noble phases to cause anodic dissolution of the iron-based matrix is promising. Due to its high electrochemical potential, immiscibility with iron, biocompatibility, and antibacterial properties, silver is suited for the creation of such phases. A suitable technology for processing immiscible material combinations is powder-bed-based procedure like laser beam melting. This procedure offers short exposure times to high temperatures and therefore a limited time for diffusion of alloying elements. As the silver phases remain after the dissolution of the iron matrix, a modification is needed to ensure their degradability. Following this strategy, pure iron with 5 wt% of a degradable silver–calcium–lanthanum alloy is processed via laser beam melting. Investigation of the microstructure yields achievement of the intended microstructure and long-term degradation tests indicates an impact on the degradation, but no increased degradation rate. 相似文献
66.
Summary Structure and dynamics of unfilled and carbon black filled natural rubber vulcanizates were investigated by means of transversal1H-NMR-relaxation. A simple theoretical model including different motions in polymer network was extended by the discussion of an anisotropy parameter of segmental motion not only for the intercrosslink chains but also for the dangling ends. It makes characterization of the filling state of the network possible to approximate. The effect of increasing correlation times f of the fast anisotropic local motion with reduction of the molecular mass of intercrosslink chains which was observed, but not cleared up in previous investigation is evidently smaller by using this modified model in accordance with the expectation of a local motion. The determined values of Mc are in good agreement with the results of fits by using the unmodified relaxation function.13C-NMR-spectra and stress-strain-experiments are leading in most cases to similar results, especially for Mc. 相似文献
67.
68.
The smart car seat: personalized monitoring of vital signs in automotive applications 总被引:1,自引:1,他引:0
Marian Walter Benjamin Eilebrecht Tobias Wartzek Steffen Leonhardt 《Personal and Ubiquitous Computing》2011,15(7):707-715
Embedded wireless sensors are important components of mobile distributed computing networks, and one of the target applications
areas is health care. The preservation of mobility for senior citizens is one of the key issues in maintaining an independent
lifestyle. Thus health technologies inside a car can contribute both to safety issues (supervision of driver fitness) as well
as healthcare issues by monitoring vitals signs imperceptibly. In this paper, three embedded measurement techniques for non-contact
monitoring of vital signals have been investigated. Specifically, capacitive electrocardiogram (cECG) monitoring, mechanical
movement analysis (ballistocardiogram, BCG) using piezo-foils and inductive impedance monitoring were examined regarding their
potential for integration into car seats. All three sensing techniques omit the need for electroconductive contact to the
human body, but require defined mechanical boundary conditions (stable distances or, in the case of BCG, frictional connection).
The physical principles of operation, the specific boundary conditions regarding automotive integration and the results during
wireless operation in a running car are presented. All three sensors were equipped with local intelligence by incorporating
a microcontroller. To eliminate the need for additional cabling, a wireless Bluetooth communication module was added and used
to transmit data to a measurement PC. Finally, preliminary results obtained during test drives on German city roads and highways
are discussed. 相似文献
69.
Stangegaard M Frøslev TG Frank-Hansen R Hansen AJ Morling N 《Journal of laboratory automation》2011,16(2):134-140
We have implemented and validated automated protocols for DNA extraction and PCR setup using a Tecan Freedom EVO liquid handler mounted with the Te-MagS magnetic separation device (Tecan, M?nnedorf, Switzerland). The protocols were validated for accredited forensic genetic work according to ISO 17025 using the Qiagen MagAttract DNA Mini M48 kit (Qiagen GmbH, Hilden, Germany) from fresh whole blood and blood from deceased individuals. The workflow was simplified by returning the DNA extracts to the original tubes minimizing the risk of misplacing samples. The tubes that originally contained the samples were washed with MilliQ water before the return of the DNA extracts. The PCR was setup in 96-well microtiter plates. The methods were validated for the kits: AmpF?STR Identifiler, SGM Plus and Yfiler (Applied Biosystems, Foster City, CA), GenePrint FFFL and PowerPlex Y (Promega, Madison, WI). The automated protocols allowed for extraction and addition of PCR master mix of 96 samples within 3.5h. In conclusion, we demonstrated that (1) DNA extraction with magnetic beads and (2) PCR setup for accredited, forensic genetic short tandem repeat typing can be implemented on a simple automated liquid handler leading to the reduction of manual work, and increased quality and throughput. 相似文献
70.
Mike Espig Wolfgang Hackbusch Stefan Handschuh Reinhold Schneider 《Computing and Visualization in Science》2011,14(6):271-285
We discuss the calculus of variations in tensor representations with a special focus on tensor networks and apply it to functionals of practical interest. The survey provides all necessary ingredients for applying minimization methods in a general setting. The important cases of target functionals which are linear and quadratic with respect to the tensor product are discussed, and combinations of these functionals are presented in detail. As an example, we consider the representation rank compression in tensor networks. For the numerical treatment, we use the nonlinear block Gauss?CSeidel method. We demonstrate the rate of convergence in numerical tests. 相似文献