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21.
Zeolitic imidazolate framework (ZIF) hybrid fluorescent nanoparticles and ZIF antibody conjugates have been synthesized, characterized, and employed in lateral-flow immunoassay (LFIA). The bright fluorescence of the conjugates and the possibility to tailor their mobility gives a huge potential for diagnostic assays. An enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase (HRP) as label, proved the integrity, stability, and dispersibility of the antibody conjugates, LC-MS/MS provided evidence that a covalent link was established between these metal-organic frameworks and lysine residues in IgG antibodies.  相似文献   
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The very strong Lewis acid aluminium chlorofluoride (ACF) was loaded with anhydrous HF. The interaction between the surface of the catalyst and HF was investigated using a variety of characterization methods, which revealed the formation of polyfluorides. Moreover, the reactivity of the HF-loaded ACF towards the hydrofluorination of alkynes was studied.  相似文献   
24.
A chiral phosphoric acid with a 2,2’-binaphthol core was prepared that displays two thioxanthone moieties at the 3,3’-position as light-harvesting antennas. Despite its relatively low triplet energy, the phosphoric acid was found to be an efficient catalyst for the enantioselective intermolecular [2+2] photocycloaddition of β-carboxyl-substituted cyclic enones (e.r. up to 93:7). Binding of the carboxylic acid to the sensitizer is suggested by NMR studies and by DFT calculations to occur by means of two hydrogen bonds. The binding event not only enables an enantioface differentiation but also modulates the triplet energy of the substrates.  相似文献   
25.
We present an existence result for Lévy‐type processes which requires only weak regularity assumptions on the symbol with respect to the space variable x. Applications range from existence and uniqueness results for Lévy‐driven SDEs with Hölder continuous coefficients to existence results for stable‐like processes and Lévy‐type processes with symbols of variable order. Moreover, we obtain heat kernel estimates for a class of Lévy and Lévy‐type processes. The paper includes an extensive list of Lévy(‐type) processes satisfying the assumptions of our results.  相似文献   
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Previous reports in the literature have suggested that concerted transition states for oxidative addition would not exist in solution. By contrast, this report describes the successful location of transition states for the oxidative addition of monoligated Pd(PtBu3), bisligated Pd(PtBu3)(MeCN), and anionic Pd(PtBu3)F? complexes to C–Cl and C–OTf of an aryl chloro triflate in polar solvent (MeCN). Optimizations were done with implicit solvation and a combined implicit/explicit solvation approach in which six acetonitrile molecules were additionally involved in the optimization. The geometries obtained from optimizations employing an implicit solvation model are structurally largely analogous to those found using a combination of implicit and explicit solvation.  相似文献   
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Hybrid polymer solutions suitable for UV-nanoimprint were synthesized by combination of an alkoxysilane binder mixture with silica nanoparticles. Hydrolysis and condensation reactions were monitored by NMR and viscosity measurements. Thereby long-term stable systems were produced as a prerequisite for industrial application. Dip-coating of glass substrates and subsequent UV-curing yielded thin films. Their thermal densification and microstructural evolution resulted in pure glassy porous coatings, which were in detail characterized by N2-sorption measurements and ellipsometric porosimetry. Results emphasize the importance of the binder-particle interaction within these materials that are destined for the fabrication of microstructured surfaces by cost efficient and industrially feasible UV-based soft lithography. Structured glassy layers with high inorganic content show thermal stability up to >500 °C and have a high structure accuracy >85 %.  相似文献   
30.
While the N-trifluoromethylation of cyclic ureas is of interest for the potential to fundamentally change the properties of these biologically relevant moieties, the single synthetic procedure known to date describing their access only gives 4,4-disubstituted or fused aromatic cyclic N-CF3 urea derivatives. We herein report an alternative approach to unleash access to the 4-monosubstituted imidazolidinone motif. The strategy relies on straightforward cyclization of readily accessible acyclic ureas, enabled by Ag-catalysis or light-assisted proton coupled electron transfer. The cyclic core is shown to be highly robust and amenable to various derivatizations, such as tandem Ni-catalysis, C−B, C−N, C−C cross couplings or C−H functionalizations, tolerating basic, nucleophilic and/or oxidizing conditions.  相似文献   
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