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1.
The design of covalent adaptable networks (CANs) relies on the ability to trigger the rearrangement of bonds within a polymer network. Simple activated alkynes are now used as versatile reversible cross‐linkers for thiols. The click‐like thiol–yne cross‐linking reaction readily enables network synthesis from polythiols through a double Michael addition with a reversible and tunable second addition step. The resulting thioacetal cross‐linking moieties are robust but dynamic linkages. A series of different activated alkynes have been synthesized and systematically probed for their ability to produce dynamic thioacetal linkages, both in kinetic studies of small molecule models, as well as in stress relaxation and creep measurements on thiol–yne‐based CANs. The results are further rationalized by DFT calculations, showing that the bond exchange rates can be significantly influenced by the choice of the activated alkyne cross‐linker.  相似文献   
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This article is concerned with notions of fuzzy-valued stochastic integrals driven by two-parameter martingales and increasing processes. We present their main properties and formulate next two-parameter fuzzy-valued stochastic integral equations. We establish the existence and uniqueness of solutions to such equations as well as their additional properties.  相似文献   
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Mechanochemistry has recently emerged as an environmentally friendly solventless synthesis method enabling a variety of transformations including those impracticable in solution. However, its application in the synthesis of well‐defined nanomaterials remains very limited. Here, we report a new bottom‐up mechanochemical strategy to rapid mild‐conditions synthesis of organic ligand‐coated ZnO nanocrystals (NCs) and their further host–guest modification with β‐cyclodextrin (β‐CD) leading to water‐soluble amide‐β‐CD‐coated ZnO NCs. The transformations can be achieved by either one‐pot sequential or one‐step three‐component process. The developed bottom‐up methodology is based on employing oxo‐zinc benzamidate, [Zn44‐O)(NHOCPh)6], as a predesigned molecular precursor undergoing mild solid‐state transformation to ZnO NCs in the presence of water in a rapid, clean and sustainable process.  相似文献   
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The geminal frustrated Lewis pair tBu2PCH2B(Fxyl)2 ( 1 ; Fxyl=3,5‐(CF3)2C6H3) is accessible in 65 % yield from tBu2PCH2Li and (Fxyl)2BF. According to NMR spectroscopy and X‐ray crystallography, 1 is monomeric both in solution and in the solid state. The intramolecular P ??? B distance of 2.900(5) Å and the full planarity of the borane site exclude any significant P/B interaction. Compound 1 readily activates a broad variety of substrates including H2, EtMe2SiH, CO2/CS2, Ph2CO, and H3CCN. Terminal alkynes react with heterolysis of the C?H bond. Haloboranes give cyclic adducts with strong P?BX3 and weak R3B?X bonds. Unprecedented transformations leading to zwitterionic XP/BCX3 adducts occur on treatment of 1 with CCl4 or CBr4 in Et2O. In less polar solvents (C6H6, n‐pentane), XP/BCX3 adduct formation is accompanied by the generation of significant amounts of XP/BX adducts. FLP 1 catalyzes the hydrogenation of PhCH=NtBu and the hydrosilylation of Ph2CO with EtMe2SiH.  相似文献   
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The reaction of silver acetate with cis-[PtI2(dbtp)2], where dbtp = 5,7-ditertbutyl-1,2,4-triazolo-[1,5-a]pyrimidine, yielded cis-[Pt(OOCCH3)2(dbtp)2]·dmf (1). The complex has been analyzed by multinuclear magnetic resonance (1H, 13C, 15N), IR, and Raman. The compound formed two rotamers in CDCl3 and its spatial structures have been optimized using computational calculation. It was found that head-to-tail rotamer (1a) is more stable than its head-to-head counterpart (1b). In vitro antiproliferative activity against four tumor cell lines (A549, T47D, FaDu, and A2780cis) revealed in all cases significant cytotoxicity (IC50 = 0.26–1.80 μM), possessing IC50 values at least fivefold lower than cisplatin, carboplatin, and oxaliplatin (except A2780cis). The remarkable in vitro activity against T47D and A2780cis suggested the ability to overcome cisplatin resistance in these types of tumor cells. In addition, in vitro toxicity was evaluated against BALB/3T3 and has shown that the lipophilic platinum(II) complex (1) inhibits cell proliferation weaker than cisplatin and oxaliplatin. Additionally, cis-[Pt(OOCCH3)2(dbtp)2]·dmf exhibited selective activity, in contrast to cisplatin or oxaliplatin.  相似文献   
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Potential Analysis - We study the quenched long time behaviour of the survival probability up to time t, $\mathbf {E}_{x}\left [e^{-{{\int }_{0}^{t}} V^{\omega }(X_{s})\mathrm {d}s}\right ],$ of a...  相似文献   
10.
Demirci  Kamil  Boccuto  Antonio  Yıldız  Sevda  Dirik  Fadime 《Positivity》2020,24(1):1-11
Positivity - We prove a Korovkin-type approximation theorem using the relative uniform convergence of a sequence of functions at a point, which is a method stronger than the classical ones. We give...  相似文献   
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