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81.
Selection of the friction electrode materials is crucial to the performance of a triboelectric nanogenerator (TENG). In the present study, a metal–organic coordination complex containing organosulfonate counteranions with electron-donating ability was synthesized through the coordination-driven self-assembly approach under mild reaction conditions and was chosen as a positive electrode material to construct a triboelectric nanogenerator, exhibiting high-output performance with a peak value of short circuit current density of 98.6 μA and an output voltage of 1180 V. As a practical application, it was shown to light up 1488 commercial green LEDs and power an anticorrosion system device to protect metals from corrosion.  相似文献   
82.
Bottom-up synthesis of π-extended macrocyclic carbon rings is promising for constructing length- and diameter-specific carbon nanotubes (CNTs). However, it is still a great challenge to realize size-controllable giant carbon macrocycles. Herein, a tunable synthesis of curved nanographene-based giant π-extended macrocyclic rings (CHBC[n]s; n=8, 6, 4), as finite models of armchair CNTs, is reported. Among them, CHBC[8] contains 336 all-carbon atoms and is the largest cyclic conjugated molecular CNT segment ever reported. CHBC[n]s were systematically characterized by various spectroscopic methods and applied in photoelectrochemical cells for the first time. This revealed that the proton chemical shifts, fluorescence, and electronic and photoelectrical properties of CHBC[n]s are highly dependent on the macrocycle diameter. The tunable bottom-up synthesis of giant macrocyclic rings could pave the way towards large π-extended diameter- and chirality-specific CNT segments.  相似文献   
83.
    
Plasmonic nanostructures with large absorption areas under resonant excitation have been utilized extensively in photon-assisted applications. In this work, dodecahedral Au nanobowls were first prepared by an easy and template-free method only through the introduction of H2PtCl6 and I during the growth procedure. The Au nanobowls show electron-field enhancement due to the high curvature of the bowl edge, the open region, and dodecahedral morphology. Au/Pt nanobowls, which couple plasmonic Au and catalytic Pt, were then constructed as plasmonic electrocatalysts for methanol oxidation. The mass activity reached 497.6 mA mg−1 under visible-light illumination, which is 1.9 times that measured in the dark. Simultaneously, the electrocatalytic stability is also greatly improved under light excitation. The enhanced properties of the plasmonic Au/Pt electrocatalysts are ascribed to the synergistic effect of the plasmon-enhanced photothermal and hot-carrier effects on the basis of experimental investigations. This work thus offers an effective methodology to construct efficient plasmonic electrocatalysts for fuel cells.  相似文献   
84.
Metalloproteins have inspired chemists for many years to synthesize artificial catalysts that mimic native enzymes.As a complementary approach to studying native enzymes or making synthetic models,biosynthetic approach using small and stable proteins to model native enzymes has offered advantages of incorporating non-covalent secondary sphere interactions under physiological conditions.However,most biosynthetic models are restricted to natural amino acids.To overcome this limitation,incorporating unnatural amino acids into the biosynthetic models has shown promises.In this review,we summarize first synthetic,semisynthetic and biological methods of incorporates unnatural amino acids(UAAs)into proteins,followed by progress made in incorporating UAAs into both native metalloproteins and their biosynthetic models to fine-tune functional properties beyond native enzymes or their variants containing natural amino acids,such as reduction potentials of azurin,O_2 reduction rates and percentages of product formation of HCO models in Mb,the rate of radical transport in ribonucleotide reductase(RNR)and the proton and electron transfer pathways in photosystemⅡ(PSⅡ).We also discuss how this endeavour has allowed systematic investigations of precise roles of conserved residues in metalloproteins,such as Metl21 in azurin,Tyr244 that is cross-linked to one of the three His ligands to CuB in HCO,Tyr122,356,730 and 731 in RNR and TyrZ in PSⅡ.These examples have demonstrated that incorporating UAAs has provided a new dimension in our efforts to mimic native enzymes and in providing deeper insights into structural features responsible high enzymatic activity and reaction mechanisms,making it possible to design highly efficient artificial catalysts with similar or even higher activity than native enzymes.  相似文献   
85.
86.
崔洪波  孙君燕 《分析化学》1992,20(7):790-793
本文对微型管状离子选择电极在流动条件下的电化学特征进行了研究,并设计了新的集成微管路离子选择以电极功能块。用此微型装置测定了土壤、血清、水和药物中的K~+、Na~+、pH、Cl~-、F~-、阿托品、东茛菪碱,并和各种标准方法作了比较,获得满意分析结果。  相似文献   
87.
Zhu  Hui  Liu  Dong  Li  Yue-Hua  Cui  Guang-Hua 《Transition Metal Chemistry》2020,45(1):19-29
Transition Metal Chemistry - Two Ag(I) complexes, namely [Ag2(L1)2(HMIP)2·H2O]n (1) and [Ag2(L2)2(HPA)2]n (2) (L1?=?1,6-bis(2-methylbenzimidazol-1-yl)hexane,...  相似文献   
88.
    
A surfactant, R-6-AO, derived from dehydroabietic acid has been synthesized. It behaves as a highly efficient low-molecular-weight hydrogelator with an extremely low critical gelation concentration (CGC) of 0.18 wt % (4 mm ). R-6-AO not only stabilizes oil-in-water (O/W) emulsions at concentrations above its critical micelle concentration (cmc) of 0.6 mm , but also forms gel emulsions at concentrations beyond the CGC with the oil volume fraction freely adjustable between 2 % and 95 %. Cryo-TEM images reveal that R-6-AO molecules self-assemble into left-handed helical fibers with cross-sectional diameters of about 10 nm in pure water, which can be turned to very stable hydrogels at concentrations above the CGC. The gel emulsions stabilized by R-6-AO can be prepared with different oils (n-dodecane, n-decane, n-octane, soybean oil, olive oil, tricaprylin) owing to the tricyclic diterpene hydrophobic structure in their molecules that enables them to adopt a unique arrangement in the fibers.  相似文献   
89.
    
An electrochemical four‐component reaction cascade Mumm rearrangement was developed. It is a rare example of in situ generation of O‐acyl isoamides for 1,3‐(O→N) acyl transfer. Inexpensive, commercially available arylethylenes, aryl or heterocyclic acids, acetonitrile, and alcohols were used as substrates. A wide range of aryl acids and alcohols were tolerated and provided imides in satisfactory yields. Subsequent hydrolysis of imides could be utilized to synthesize valuable amides and β‐amino alcohol derivatives.  相似文献   
90.
    
Hydrosilylation of alkynes generally yield vinylsilanes, which are inert to the further hydrosilylation because of the steric effects. Reported here is the first successful dihydrosilylation of aryl‐ and silyl‐substituted internal alkynes enabled by a rare‐earth ate complex to yield geminal bis‐ and tris(silanes), respectively. The lanthanum bis(amido) ate complex supported by an ene‐diamido ligand proved to be the ideal catalyst for this unprecedented transformation, while the same series of yttrium and samarium alkyl and samarium bis(amido) ate complexes exhibited poor activity and selectivity, indicating significant effects of the ionic size and ate structure of the rare‐earth catalysts.  相似文献   
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