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1.
We report a stereoselective conversion of terminal alkynes to α-chiral carboxylic acids using a nickel-catalyzed domino hydrocarboxylation-transfer hydrogenation reaction. A simple nickel/BenzP* catalyst displayed high activity in both steps of regioselective hydrocarboxylation of alkynes and subsequent asymmetric transfer hydrogenation. The reaction was successfully applied in enantioselective preparation of three nonsteroidal anti-inflammatory profens (>90 % ees) and the chiral fragment of AZD2716.  相似文献   
2.
Natural fibers containing components with phenolic hydroxyl groups, such as jute, wool, and silk, can be directly modified by laccase-catalyzed grafting. However, cellulosic fibers like cotton cannot be functionalized in this manner. In this work, we developed a facile two-step method to graft polymers on cotton fabric via laccase catalysis. First, polydopamine (PDA) coating was deposited on the surface of the cotton fabrics via catalysis of laccase/2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) system. Then, the newly formed PDA coating acted as the secondary reaction platform for subsequent laccase-mediated grafting of hydrophobic monomer dodecyl gallate (DG). The oxidation of dopamine (DA) catalyzed with the laccase/TEMPO system was investigated using UV–visible (UV–vis) spectroscopy. The scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) results verified that the PDA was coated on the surface of cotton fibers. Fourier transform infrared (FTIR) spectra indicated that the PDA-coated cotton was successfully grafted with DG (DG-PDA-cotton). According to the weighting method, the grafting percentage was about 1.06%. The hydrophobicity of the DG-PDA-cotton fabrics was greatly improved with a contact angle of 133°. Also, the grafted cotton fabrics show repellency of water-soluble stains like coffee, milk, and tea. This study provides a new strategy for surface modification of cotton by laccase-mediated grafting, which offers the references for the green fabrication of cotton fabrics with improved functionalization.  相似文献   
3.
Current three-dimensional micromixers for continuous flow reactions and nanoparticle synthesis are complex in structure and difficult to fabricate. This paper investigates the design, fabrication, and characterization of a novel micromixer that uses a simple spatial Tesla valve design to achieve efficient mixing of multiple solutions. The flow characteristics and mixing efficiencies of our Tesla valve micromixer are investigated using a combination of numerical simulations and experiments. The results show that in a wide range of flow rates, viscoelastic solutions with different concentrations can be well mixed in our micromixer. Finally, experiments on the synthesis of chitosan nanoparticles are conducted to verify the practicability of our micromixer. Compared with nanoparticles prepared by conventional magnetic stirring, the size of nanoparticles prepared by micromixing is smaller and the distribution is more uniform. Therefore, our Tesla valve micromixer has significant advantages and implications for mixing chemical and biological reactions.  相似文献   
4.
Journal of Radioanalytical and Nuclear Chemistry - When monitoring radioactive aerosol in the atmosphere, choosing a filter membrane with better surface collection characteristics and filtering...  相似文献   
5.
Journal of Radioanalytical and Nuclear Chemistry - In this work, zeolitic imidazolate framework-8 (ZIF-8) with a microporous structure for 60Co and 54Mn adsorption was prepared at room temperature,...  相似文献   
6.
Hu  Eming  Lei  Zhiwu  Wang  Hongqiang  Su  Hao  Zhou  Wen  Wan  Qiang  Zhu  Fangping  Wang  Qingliang 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2445-2450
Journal of Radioanalytical and Nuclear Chemistry - The uraniferous caustic sludge (UCS) produced in the production of uranium fuel components was hardly to leach directly, due to its very low-grade...  相似文献   
7.
Journal of Radioanalytical and Nuclear Chemistry - Soil radon anomaly is a common phenomenon in karst areas. In this paper, the geochemical behavior of radium (Ra) in the process of carbonate rock...  相似文献   
8.
Journal of Radioanalytical and Nuclear Chemistry - Prostate-specific membrane antigen (PSMA)-targeted radiolabeled agents have been developed to diagnose and treat prostate cancer. In this study,...  相似文献   
9.
Journal of Radioanalytical and Nuclear Chemistry - In this study, a dynamic nuclide identification algorithm based on fuzzy probability factor superposition (FPFS) was proposed for γ spectrum...  相似文献   
10.
Chen  Kuang  Zhang  Xiaojun  Wang  Fei  Wu  Yitian  Zhou  Haoxi  Zhang  Ying  Zou  Wenbo  Zhang  Jinming  Liu  Rong 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(7):2859-2868
Journal of Radioanalytical and Nuclear Chemistry - This study evaluated the potential of Al18F-labelled restrained complexing agent (RESCA)-ICG to assess hepatic function reserve on PET/CT imaging....  相似文献   
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