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991.
992.
993.
In this paper, the results of the study of the reduction of basic lead sulphate with a gas (CO + CO2) mixture are presented. This is a secondary reaction during the reduction of lead sulphate. The change in the both lead and PbS content in the reaction products, depending on the process temperature and the composition of the gaseous phase, was established. The comparison of the rate of the reduction reaction of lead sulphate and basic lead sulphate shows that the process proceeding with a higher output is the reduction of basic lead sulphate.  相似文献   
994.
Polyaniline (PANI)/Au composite nanotubes were synthesized and developed as an electrode material for a nicotinamide adenine dinucleotide (NADH) sensor. A MnO2 self-degradable template method was used to prepare the tube-like PANI nanomaterial. By introducing PANI nanotubes into Au colloid, Au nanoparticles (NPs) were successfully decorated onto the surface of PANI nanotubes through electrostatic effects. The morphology, composition, and optical properties of the resulting products were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) absorption spectra, and thermogravimetric analysis (TGA). In addition, the obtained PANI/Au composites were used as catalysts for the electrochemical oxidation of NADH. Cyclic voltammogram (CV) experiments indicated that PANI/Au-modified glassy carbon electrode showed a higher electrocatalytic activity towards the oxidation of NADH in a neutral environment. Differential pulse voltammogram (DPV) results illustrated that the fabricated NADH sensor had excellent anti-interference ability and displayed a wide linear range from 4?×?10?4 to 8?×?10?3 M with a detection limit of 0.5?×?10?7 M.  相似文献   
995.
There is an urgent need for the development in the field of the magnetism of topological insulators, owing to the necessity for the realization of the quantum anomalous Hall effect. Herein, we discuss experimentally fabricated nanostructured hierarchical architectures of the topological insulator Bi2Te3 without the introduction of any exotic magnetic dopants, in which intriguing room‐temperature ferromagnetism was identified. First‐principles calculations demonstrated that the intrinsic point defect with respect to the antisite Te site is responsible for the creation of a magnetic moment. Such a mechanism, which is different from that of a vacancy defect, provides new insights into the origins of magnetism. Our findings may pave the way for developing future Bi2Te3‐based dissipationless spintronics and fault‐tolerant quantum computation.  相似文献   
996.
A coupling reaction of N‐phenoxyacetamides with N‐tosylhydrazones or diazoesters through RhIII‐catalyzed C? H activation is reported. In this reaction, ortho‐alkenyl phenols were obtained in good yields and with excellent regio‐ and stereoselectivity. Rh–carbene migratory insertion is proposed as the key step in the reaction mechanism.  相似文献   
997.
Magnolol and honokiol as pharmaceutical ligands have been introduced into terbium complex systems for the first time and two hybrid organic–inorganic materials were successfully prepared. Both of them can sensitize terbium characteristic green emission effectively based on intra-molecular energy transfer channel. Moreover, they selectively recognized Cu2+ and Fe3+ through luminescence quenching effects. The photophysical properties and morphological structures were extensively investigated.  相似文献   
998.
We present the isolation of the first mononuclear dihalogermylene, and mono‐ and dinuclear stannylene complexes of transition metals. These exhibit exceptionally pyramidalized Group 14 centers. Additionally, removal of the halide substituents from the Ge/Sn atom was successfully performed in two ways, halide abstraction and reduction, leading to a variety of unusual structural motifs.  相似文献   
999.
A magnesium‐catalyzed asymmetric ring‐opening reaction of aziridine with indole has been realized by employing commercially available chiral ligands. Both of the enantiomers of the ring‐opening product could be obtained with good yields and a high level of enantioselectivity. The corresponding ring‐opening product could be further transformed to various types of enantioenriched C3‐halogenated‐pyrroloindolines.  相似文献   
1000.
cis‐2,6‐Tetrahydropyran is an important structural skeleton of bioactive natural products. A facile synthesis of cis‐2,6‐disubstituted‐3,6‐dihydropyrans as cis‐2,6‐tetrahydropyran precursors has been achieved in high regio‐ and stereoselectivity with high yields. This reaction involves a palladium‐catalyzed decarboxylative allylation of various 3,4‐dihydro‐2H‐pyran substrates. Extending this reaction to 1,2‐unsaturated carbohydrates allowed the achievement of challenging β‐C‐glycosylation. Based on this methodology, the total syntheses of (±)‐centrolobine and (+)‐decytospolides A and B were achieved in concise steps and overall high yields.  相似文献   
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