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31.
Matthias Müller Dr. Magnus R. Buchner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):9915-9922
The first synthesis of BePh2 was accomplished almost a century ago. However, its structure has remained unknown so far, while the corresponding aryls of the elements adjacent to beryllium in the periodic table are well investigated. Herein, we present an improved synthesis for diphenylberyllium and show by X-ray diffraction that it forms a trinuclear complex in the solid state. NMR spectroscopy revealed that this structure is also retained in solution but exhibits dynamic behavior. Its stability against heat and coordinating solvents is discussed and the possible obstacles to the synthesis of BePh2 from BeCl2 are examined. In the process of this study two ether adducts, BePh2⋅Et2O and Be2Ph4⋅Et2O, have been characterized as well as the previously unknown triphenylberyllate anion. From the latter several single-crystal structures were obtained under various conditions, in which [BePh3]− is either isolated or acts as a ligand for Li+. Furthermore, the crown ether induced selfionization of BePh2 is described and the resulting [(12-crown-4)BePh]+ cation was isolated, which shows an unusual 4+1 coordination around the Be atom. 相似文献
32.
Jun Kawahara Peter Andersson Ersman David Nilsson Kazuya Katoh Yasukazu Nakata Mats Sandberg Marie Nilsson Göran Gustafsson Magnus Berggren 《Journal of Polymer Science.Polymer Physics》2013,51(4):265-271
A flexible electrochromic active matrix addressed display, including 8 × 8 pixels, is demonstrated by using solution processing based on standard printing and coating manufacturing techniques. Each organic electrochromic display (OECD) pixel and its corresponding organic electrochemical transistor (OECT) are located on different sides of the flexible PET substrate. Electronic vias generated through the plastic substrate connects each OECD pixel with one addressing OECT. When comparing this display with actively addressed OECDs with all its components located on the same side, the present approach based on this electronic via substrate provides an enhanced pixel resolution and a relatively more simplified manufacturing process. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
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Cláudia A. Kodaira Ana Valéria S. Lourenço Maria Cláudia F.C. Felinto Eduardo M.R. Sanchez Francisco J.O. Rios Luiz Antonio O. Nunes Magnus Gidlund Oscar L. Malta Hermi F. Brito 《Journal of luminescence》2011,131(4):727-731
Neodymium based fluorescence presents several advantages in comparison to conventional rare earth or enzyme-substrate based fluorescence emitting sources (e.g.Tb, HRP) . Based on this fact we have herein explored a Nd-based fluoroimmunoassay. We efficiently detected the presence of an oxidized low-density lipoprotein (oxLDL) in human plasma a well-known marker for cardiovascular diseases, which causes around 30% of deaths worldwide. Conventional fluoroimmunoassay uses time-resolved luminescence techniques, with detection in the visible range, to eliminate the fluorescence background from the biological specimens. By using an immunoassay based on functionalized Y2O3:Nd3+ nanoparticles, where the excitation and emission processes in the Nd3+ ion occur in the near-infrared (NIR) region, we have succeeded in eliminating the interferences from the biological fluorescence background, avoiding the use of time-resolved techniques. This yields higher emission intensity from the Nd3+-nanolabels and efficient detection of anti-oxidized low-density lipoproteins (anti-oxLDL) by Y2O3:Nd3+-antibody-antigen conjugation, leading to a novel biolabeling method. 相似文献
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Nahid Amini Ryuji Nakao Magnus Schou Christer Halldin 《Analytical and bioanalytical chemistry》2013,405(4):1303-1310
A general method is presented for the identification of radiometabolites in plasma of human and monkey subjects after administration of positron emission tomography (PET) radioligands. The radiometabolites are first produced in vitro, using liver microsomes, subsequently separated using fast radio-liquid chromatography (radio-LC), and individually collected and identified by ultra high-performance liquid chromatography/quadrupole-time of flight-mass spectrometry in MS and MSE mode. Fast radio-LC provided superior resolution compared to conventional radio-LC, resulting in separation of a greater number of metabolites. The radiometabolites produced in vivo are then compared to and identified based on the in vitro results. This approach was applied to three PET radioligands, [11C]flumazenil, [18F]FE-PE2I, and [11C]PBR28, resulting in the identification of five, two, and one radiometabolites, respectively. This procedure can easily be adopted to identify the radiometabolites produced in vivo from a variety of PET radioligands. 相似文献
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We present a new implementation of a recent open‐ended response theory formulation for time‐ and perturbation‐dependent basis sets (Thorvaldsen et al., J. Chem. Phys. 2008, 129, 214108) at the Hartree–Fock and density functional levels of theory. A novel feature of the new implementation is the use of recursive programming techniques, making it possible to write highly compact code for the analytic calculation of any response property at any valid choice of rule for the order of perturbation at which to include perturbed density matrices. The formalism is expressed in terms of the density matrix in the atomic orbital basis, allowing the recursive scheme presented here to be used in linear‐scaling formulations of response theory as well as with two‐ and four‐component relativistic wave functions. To demonstrate the new code, we present calculations of the third geometrical derivatives of the frequency‐dependent second hyperpolarizability for HSOH at the Hartree–Fock level of theory, a seventh‐order energy derivative involving basis sets that are both time and perturbation dependent. © 2014 Wiley Periodicals, Inc. 相似文献