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991.
Xiao-Ling Zhang Li Zhang Ya-Ling Ye Xiang-Hui Li Dr. Bi-Lian Ni Prof. Ying Li Dr. Wei-Ming Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(3):1039-1045
Developing efficient catalysts for the conversion of CO2 into fuels and value-added chemicals is of great significance to relieve the growing energy crisis and global warming. With the assistance of DFT calculations, it was found that, different from Al12X (X=Be, Al, and C), the alkali-metal-like superatom Al12P prefers to combine with CO2 via a bidentate double oxygen coordination, yielding a stable Al12P(η2-O2C) complex containing an activated radical anion of CO2 (i.e., CO2.−). Thereby, this compound could not only participate in the subsequent cycloaddition reaction with propylene oxide but also initiate the radical reaction with hydrogen gas to form high-value chemicals, revealing that Al12P can play an important role in catalyzing these conversion reactions. Considering that Al12P has been produced in laboratory and is capable of absorbing visible light to drive the activation and transformation of CO2, it is anticipated that this work could guide the discovery of additional superatom catalysts for CO2 transformation and open up a new research field of superatom catalysis. 相似文献
992.
We observed a novel voltage peak in the proximity-induced superconducting gold (Au) nanowire while cooling the sample through the superconducting transition temperature. The voltage peak turned dip during warming. The voltage peak or dip was found to originate respectively from the emergence or vanishing of the proximity-induced superconductivity in the Au nanowire. The amplitude of the voltage signal depends on the temperature scanning rate, and it cannot be detected when the temperature is changed slower than 0.03 K/min. This transient feature suggests the non-equilibrium property of the effect. Ginzburg-Landau model clarified the voltage peak by considering the emergence of Cooper pairs of relatively lower free energy in superconducting W contact and the non-equilibrium diffusion of Cooper pairs and quasiparticles. 相似文献
993.
Journal of Radioanalytical and Nuclear Chemistry - As a result of nuclear power plant accidents such as Chernobyl and Fukushima, and even their maintenance, the soil is contaminated due to the... 相似文献
994.
A novel Pt/C‐catalyzed transfer hydrogenation reaction of p‐benzoquinone to produce p‐hydroquinone using cyclohexanone as an unexpectedly effective hydrogen source 下载免费PDF全文
A new method for the production of p‐hydroquinone via a Pt/C‐catalyzed reduction of p‐benzoquinone is developed. Different from the conventional transfer hydrogenation reactions that usually use secondary alcohols such as isopropanol as the hydrogen source, in this work, it is unexpectedly found that cyclohexanone is a more effective hydrogen source than secondary alcohols, even cyclohexanol. This reaction affords acceptable yields of p‐hydroquinone with very high turnover number (1109) of the Pt/C catalyst. A mechanism of this interesting reaction is proposed on the basis of the results of a series of control experiments, GC–MS analysis as well as dynamic studies. 相似文献
995.
996.
Songling Li Pengli Zhu Tao Zhao Rong Sun 《Journal of Sol-Gel Science and Technology》2014,70(3):366-370
Antimony doped tin dioxide (ATO) nanoparticles with different Sb doping contents were prepared by freeze-drying the precursor gel and then calcined procedure. The obtained ATO nanoparticles were characterized by X-ray diffraction, scanning electron microscope, optical and electrical techniques. Results indicated that ATO with 10 mol% Sb doping is optimal, with which had the lowest resistivity and highest transmittance in visible region as well as narrow particle size distribution. Thermal insulation properties of ATO/waterborne polyurethane (WPU) films coating on the glass substrates with different thickness were studied on a DIY heat insulating measurement box and showed that the glass coated with ATO/WPU films possessed better heat-insulating effect than empty glass . 相似文献
997.
Inspired by engineering of high-speed switching with quality of service, this paper introduces a new approach to classify finite lattices by the concept of cut-through coding. An n-ary cut-through code of a finite lattice encodes all lattice elements by distinct n-ary strings of a uniform length such that for all j, the initial j encoding symbols of any two elements x and y determine the initial j encoding symbols of the meet and join of x and y. In terms of lattice congruences, some basic criteria are derived to characterize the n-ary cut-through codability of a finite lattice. N-ary cut-through codability also gives rise to a new classification of lattice varieties and in particular, defines a chain of ideals in the lattice of lattice varieties. 相似文献
998.
Yu Chen Youyi Zhao Ming Wang Hao Sun Yunfa Dong Xu Feng 《Chemistry of Natural Compounds》2012,47(6):940-943
An original triterpenoid saponin, named lonimacranthoide I, was isolated from the flower buds of Lonicera macranthoides (Caprifoliaceae). It has hederagenin as aglycone. Lonimacranthoide I is a rare chlorogenic acid ester acylated at C-23 of
hederagenin. The structure of the saponin was established based on chemical and spectral methods. 相似文献
999.
A novel one-pot protocol for the synthesis of substituted 2-aminooxazoline from isonitriles and 2-aminoethanol was developed and the reactions involved imidoyl diiodide intermediates,which were generated by mixing isonitriles and iodine in CH2C12 at room temperature. 相似文献
1000.
Linghan Xiao Xin Zheng Tianyi Zhao Liying Sun Fengqi Liu Ge Gao Alideertu Dong 《Colloid and polymer science》2013,291(10):2359-2364
A novel route was introduced to synthesize dense polyacrylamide (PAM) onto the glass slide surface. To investigate the surface chemistry of the PAM on the glass slides, X-ray photoelectron spectroscopy (XPS) was utilized to obtain detailed chemical state information on the PAM layer constituents. The XPS peak data were consistent with the presented model of the PAM on the glass slide surface. Scanning electron microscopy and atomic force microscope data indicated the presence of PAM on the glass slides, which consist of nodules. The results showed that PAM was successfully immobilized onto glass slides with a two-tier structure under aqueous condition and a monolayer structure under anhydrous condition. Compared with those under aqueous condition, the controllability of the molecular layer on glass slides and the reproducibility under anhydrous condition were much better, which makes anhydrous condition an advisable condition for the study of the reaction mechanisms of glass slides modified by PAM. 相似文献