Publications by authors named "T S Seifert"
A series of seven-coordinated monoporphyrinate rare-earth(III) complexes featuring a novel tripodal tin-chelated trisphosphineoxide scorpionate ligand with the general formula [(TPP)Ln(PPhO)Sn] (Ln = Y, La, Dy, Er, Ho, Yb; TPP = 5,10,15,20-tetraphenylporphyrinate) were synthesized by reactions of the potassium tripodal scorpionate ligand [Sn(PPhO)K] with porphyrinate rare-earth metal chlorides [(TPP)LnCl(dme)] (Ln = Y, Dy, Er, Ho, Yb) or porphyrinate lanthanum borohydride [(TPP)LaBH(thf)]. The complexes were characterized by single-crystal X-ray diffraction, NMR spectroscopy, and ion mobility mass spectrometry. All complexes emit weak red TPP-based fluorescence, accompanied by near-infrared emission of Er, Ho (rather weak), and Yb (relatively intense with a quantum yield of 1% in dichloromethane solution) of the corresponding complexes.
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- Spintronic terahertz emitters (STEs) are powerful terahertz sources that can operate across a wide range of pumping frequencies, yet their performance is ultimately limited by their optical damage threshold.
- Recent advancements in technology require STEs to pump at higher megahertz rates rather than the traditional kilohertz rates, highlighting a gap in research on this topic.
- The study introduces a new classification of the optical damage threshold based on repetition rates and identifies temperature-driven inter-layer diffusion as the main failure cause, offering insights for improving STE performance in future applications.
Article Synopsis
- Researchers studied the impact of mRNA SARS-CoV-2 vaccines on patients with autoimmune liver diseases to see if vaccination worsened their conditions.
- A total of 49 patients with primary biliary cholangitis (PBC), 35 with autoimmune hepatitis (AIH), and 9 with primary sclerosing cholangitis (PSC) were tested for autoantibodies before and after vaccination, with results indicating higher rates of autoantibody positivity in liver disease patients compared to healthcare workers.
- Despite some fluctuations in autoantibody levels following vaccination, the study concluded that mRNA vaccines do not cause significant short-term worsening of autoimmunity in these patients.
Enantiospecific effects play an uprising role in chemistry and technical applications. Chiral molecular networks formed by self-assembly processes at surfaces can be imaged by scanning probe microscopy (SPM). Low contrast and high noise in the topography map often interfere with the automatic image analysis using classical methods.
View Article and Find Full Text PDFThin-film stacks | consisting of a ferromagnetic-metal layer and a heavy-metal layer are spintronic model systems. Here, we present a method to measure the ultrabroadband spin conductance across a layer between and at terahertz frequencies, which are the natural frequencies of spin-transport dynamics. We apply our approach to MgO tunneling barriers with thickness = 0-6 Å.
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