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81.
Kathrin Brmmel Sarah Maskri Ivan Maisuls Christian Paul Konken Marius Rieke Zoltan Peth Cristian A. Strassert Oliver Koch Albrecht Schwab Bernhard Wünsch 《Angewandte Chemie (International ed. in English)》2020,59(21):8277-8284
Small‐molecule probes for the in vitro imaging of KCa3.1 channel‐expressing cells were developed. Senicapoc, showing high affinity and selectivity for the KCa3.1 channels, was chosen as the targeting component. BODIPY dyes 15 – 20 were synthesized and connected by a CuI‐catalyzed azide–alkyne [3+2]cycloaddition with propargyl ether senicapoc derivative 8 , yielding fluorescently labeled ligands 21 – 26 . The dimethylpyrrole‐based imaging probes 25 and 26 allow staining of KCa3.1 channels in NSCLC cells. The specificity was shown by removing the punctate staining pattern by pre‐incubation with senicapoc. The density of KCa3.1 channels detected with 25 and by immunostaining was identical. The punctate structure of the labeled channels could also be observed in living cells. Molecular modeling showed binding of the senicapoc‐targeting component towards the binding site within the ion channel and orientation of the linker with the dye along the inner surface of the ion channel. 相似文献
82.
83.
Xinjiang Cui Wu Li Kathrin Junge Zhaofu Fei Matthias Beller Paul J. Dyson 《Angewandte Chemie (International ed. in English)》2020,59(19):7501-7507
Core–shell nanocatalysts are attractive due to their versatility and stability. Here, we describe cobalt nanoparticles encapsulated within graphitic shells prepared via the pyrolysis of a cationic poly‐ionic liquid (PIL) with a cobalt(II) chloride anion. The resulting material has a core–shell structure that displays excellent activity and selectivity in the self‐dehydrogenation and hetero‐dehydrogenation of primary amines to their corresponding imines. Furthermore, the catalyst exhibits excellent activity in the synthesis of secondary imines from substrates with various reducible functional groups (C=C, C≡C and C≡N) and amino acid derivatives. 相似文献
84.
Hg1−xCdxTe layers on CdTe substrates were grown from Te-rich melt solutions by a vertical dipping technique using a special quasi-closed system with ground-glass sealing. Results are good reproducibilities of the electrical properties after annealing in Hg-rich atmosphere (p77 ≈ 2 · 1016 cm−3 μ77 ≈ 500 cm2 V−1 s−1) and of the x-value, respectively. A horizontal position of the substrate downwards to the melt solution yields, in difference to a vertical one, to homogeneous layer thicknesses. Short meltback steps before growth leads to sharper profiles of composition. 相似文献
85.
Cokes rich in sulphur usually show throughout the high temperature treatment between 1500 and 1800 °C an irreversible dilatation which can be suppressed by additives of inorganic oxides or salts. In brown coal pitch cokes with high content of sulphur and mineral impurities (ash), however, this suphur puffing cannot be observed. Basic ash components (e. g. CaO, Fe2O3, MgO) are responsible for the puffing inhibition. The inhibition is already sufficient if the concerntration of basic ash components equals the suphur conentration. 相似文献
86.
Röntgenographically identified single-phase ZnSiP2 of stoichiometric composition which has been grown in gas phase has a specific resistance of > 103 Ωcm and locally limited luminescence spectra. The presence of foreign phases and inhomogeneities as well as stoichiometric deviations in the ZnSiP2 are possible causes of these physical properties. An attempt was made to grow, in the gas phase, ZnSiP2 containing foreign phases. For this purpose, synthesis and crystallization of ZnSiP2 were carried out using non-stoichiometric proportions of silicon. The phase composition of the crystals was investigated by means of light microscopy and electron-beam microanalysis. In the case of hypostoichiometric silicon amounts (–50 mole% Si) the ZnSiP2 matrix contains the binary phases ZnP2 and Zn3P2. Under hyperstoichiometric conditions (> 100 mole% Si) ZnS13P2 layers are deposited on the ZnSiP2. Distinct differences between the physical properties of stoichiometric single-phase ZnSiP2 and ZnSiP2 containing foreign phases could not be detected. 相似文献
87.
88.
Jrg Schappel Kathrin Schmidt Elisabeth Klemm 《Journal of polymer science. Part A, Polymer chemistry》2005,43(16):3574-3587
A Sonogashira polycondensation reaction has been used to synthesize copolymers consisting of alternating oligo(p‐phenyleneethynylene) with a precise block length as an electron‐rich component and 1,4‐bis(2‐phenylene‐2‐cyanovinylene)benzene or 2,6‐bis(2‐pyridinylene‐ethynylene)pyridine as an electron‐poor component. The copolymers differ in the length of the phenyleneethynylene block (trimer or pentamer) and the content of the electron‐poor component. The length of the phenyleneethynylene block has no influence on the maximum wavelength. The electron‐poor cyano‐block component lowers the optical band‐gap energy of the copolymers. The value is equivalent to that of poly(cyano‐phenylenevinylene) (CN‐PPV) (2.3–2.4 eV). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3574–3587, 2005 相似文献
89.
Andrews recently introduced k-marked Durfee symbols, which area generalization of partitions that are connected to momentsof Dyson's rank statistic. He used these connections to findidentities relating to their generating functions as well asto prove Ramanujan-type congruences for these objects and findrelations between them. In this paper, we show that the hypergeometricgenerating functions for these objects are natural examplesof quasimock theta functions, which are defined as the holomorphicparts of harmonic Maass forms and their derivatives. In particular,these generating functions may be viewed as analogs of Ramanujan'smock theta functions with arbitrarily high weight. We use theautomorphic properties to prove the existence of infinitelymany congruences for the Durfee symbols. Furthermore, we showthat as k varies, the modularity of the k-marked Durfee symbolsis precisely dictated by the case k = 2. Finally, we use thisrelation in order to prove the existence of general congruencesfor rank moments in terms of level one modular forms of boundedweight. 相似文献
90.