KITopen
Not a member yet
63711 research outputs found
Sort by
Hollowed and perforated fins in latent heat storage units for High-Temperature hybrid thermal energy storage applications
No full textSingle atomic Co decorated mesoporous carbon/MXene heterostructure as redox promoters for high-stable Li–S battery
No full textSequential Evaporation of Inverted FAPbI 3 Perovskite Solar Cells – Impact of Substrate on Crystallization and Film Formation
No full textMachine Learning Models for Daily Rainfall Forecasting in Northern Tropical Africa Using Tropical Wave Predictors
No full textAn undergraduate lab experiment on matched filtering as used in gravitational wave detection
No full textThe detection of gravitational waves using matched filtering algorithms is just one example of the critical role that computational data analysis plays in contemporary physics. We present an undergraduate laboratory experiment where students apply matched filtering methods to detect weak signals in their noisy measurement data. The experiment is based on a Michelson interferometer and requires little additional equipment. To make the experiment accessible to students without programming skills, we developed an open-source graphical user interface for the matched filter search, which is also presented in this article. Finally, we demonstrate the ability to detect weak signals obtained with the experimental setup described here
Synthesis and oxidation of Ru-doped UO2
Full text linkRu-doped UO2 materials were synthesized via a sol–gel method and the resulting compounds were subjected to an oxidative heat treatment at 1000 °C. Both as-synthesized and oxidized materials were characterized coupling microscopy, diffraction and spectroscopic techniques. A detailed structural description of the studied compounds is provided. The oxidation of UO2 to U3O8 is complete within the investigated atmosphere and Ru is oxidized to volatile oxide forms
Dibenzazepine Bridged Network Polymeric Phthalocyanines as Degradable Heterogeneous Photocatalysts
Full text linkRecyclability and energy efficiency are inevitable requirements in today´s synthetic materials, as well as functional efficiency. Network polymeric phthalocyanines (NP-Pcs) are versatile molecular frameworks which widely utilized in energy and electron transfer demanding applications, but light hasn´t played a role before in their “design and degradation”. Herein, we introduce photodynamic dibenzazepine moiety into NP-Pcs to obtain degradable heterogeneous photocatalysts (NP-ZnPc and NP-CoPc). Singlet oxygen generation efficiency of NP-ZnPc is found to be high, almost completely quenching the absorbance of diphenylisobenzofuran (DPBF) within 30 s upon red light (λ = 630 nm) irradiation. Supplementary reactions show that NP-ZnPc has the capability to oxidize methylphenyl sulfide with 100% yield in 4 h reaction time. Subsequently, PET-RAFT polymerization of 2-hydroxyethyl methacrylate is successfully initiated by NP-ZnPc in the presence of a chain transfer agent upon red light (λ = 647 nm) irradiation. The linearity in the increase in molecular weight (14,400–21,200 g/mol) and the decrease in monomer concentration (ln([M]0/[M] = 0.6–3.4) demonstrate the living characteristic of PET-RAFT polymerization. Thanks to its heterogeneous nature, NP-ZnPc is readily recovered and reused after polymerization up to three consecutive cycles without significant loss of performance. Notably, complete degradation of NP-Pcs was achieved under 254 nm light irradiation
Adaptive production control for agile disassembly systems in remanufacturing
Full text linkUncertainties in disassembly lead to low efficiency and high disassembly costs, prohibiting remanufacturing for economic reasons. While agile hybrid disassembly systems (AHDS) could provide a capable platform, they require a sophisticated production planning and control (PPC). This work presents a dynamic production planning and control approach for disassembly (D-PPC) for AHDS, consisting of a reactive control with CONWIP order release and an automated logically adapting Multi-Priority Rule order allocation. Results show that the approach can handle disruptions due to process failure and leads to improved throughput and lower costs, especially reducing delay costs
Synthese und Charakterisierung ortho-kondensierter Azapolycyclen
No full textHelicene sind axial-chirale ortho-anellierte polycyclische aromatische Verbindungen. Diese schraubenförmigen Verbindungen haben nicht nur eine faszinierende Struktur, sondern werden aufgrund ihrer besonderen chemischen, opto- und elektrophysikalischen Eigenschaften z. B. als Katalysatoren in der asymmetrischen Synthese, molekulare Sensoren und Schalter oder als neue Materialien für organische Leuchtdioden untersucht.
In der vorliegenden Arbeit wurden basierend auf der Methode der ortho-Cyclisierung generalisierte Synthesestrategien zur Darstellung von Azahelicenen mit elektronenreichen pyrrol- und elektronendefizienten pyridin- oder pyridazinhaltigen Teilstrukturen erarbeitet. Mehrere Arten von Aza[5]helicenen, Aza[7]helicenen, Helicen Konjugaten und von nichthelikalen Azapolycylcen wurden erfolgreich hergestellt und im Hinblick auf mögliche Anwendungen umfassend derivatisiert und charakterisiert. Die Verbindungen zeigen Acidochromie, Fluoreszenzen bis in den orangen sichtbaren Bereich und mitunter ein ausgeprägtes aggregationsverstärktes Fluoreszenzverhalten sowie eine Rotverschiebung der Emission durch Aggregation in wässrigen Lösungen