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991.
Zirui Song Kangyu Zou Xuhuan Xiao Xinglan Deng Shuo Li Prof. Dr. Hongshuai Hou Prof. Dr. Xiaoming Lou Prof. Dr. Guoqiang Zou Prof. Dr. Xiaobo Ji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16082-16092
Nowadays sodium-based energy storage systems (Na-based ESSs) have been widely researched as it possesses the possibility to replace traditional energy storage media to become next generation energy storage system. However, due to the irreversible loss of sodium ions in the first cycle, development of Na-based ESSs is limited. Presodiation, as a strategy of adding excess sodium ions to the system in advance, accomplishes the enhancement of electrochemical performance. In this minireview, different presodiation strategies applied in sodium-based energy storage systems will be summarized in detail, their functions and corresponding mechanisms will be discussed as well. Furthermore, the current novel application of presodiation method in other aspects of Na-based ESSs will be mentioned additionally. At last, in the view of present research status of presodiation, issues that can be mitigated are put forward and guidelines are given on how to deliberate in-depth presodiation technology in the future, dedicating to promote the further development of Na-based ESSs. 相似文献
992.
A new sandwiched polyoxometalate [HK11Cd4Cl2(PW9034)2]·18H2O (1), incor- porating a unique hybrid tetranuclear cadmium cluster (abbreviated to {Cd4}) with two trivacant polyanions [B-α-PW9O34]9-, has been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, UV-vis, and single-crystal X-ray diffraction analysis. Crystal data for 1: monoclinic, space group C2/c, a = 19.2997(4), b = 13.8014(3), c = 31.9819(8) A, β = 102.764(2)°, V= 8308.3(3) A3, Z = 4, P2O86Cl2K11Cd4W18H37, Mr = 5735.13, Dc = 4.584 mg-mm-3, F(000) = 10084, μ = 26.579 mm-1, the final R = 0.0378 and wR = 0.0989 for 6558 observed reflections (I〉 2σ(I)). X-ray crystallographic study shows that the molecular structure of 1 contains four cadmium atoms. Two CdO6 distorted octahedra and two CdOsC1 distorted octahedra combine with each other in turn via edge-sharing, resulting in a regular rhomb-like cluster sandwiched between two {B-a-PW9034} units. Further, the sandwich-type polyoxoanions were connected by K+ ions to form a complicated 3-D open-framework through connecting with each terminal O atom of the [Cd4C12(PW9O34)2]12- polyoxoanions. In addition, compound 1 exhibits photoluminescence property at room temperature and the band gap can be assessed at 3.25 eV. 相似文献
993.
Hui Mei Wenjia Han Jianglin Hu Se Xiao Yizhu Lei Rui Zhang Wanlin Mo Guangxing Li 《应用有机金属化学》2013,27(3):177-183
This work describes a highly efficient unstrained C(sp3)―N bond activation approach for synthesis of N,N‐dimethylacetamide (DMAc) via catalytic carbonylation of trimethylamine using a PdCl2/bipy (bipy = 2,2′‐bipyridine)/Me4NI catalyst system. A low Pd catalyst dosage (1.0 mol%) is sufficient for high selectivity (98.1%) and yield (90.8%), with a turnover number (TON) of 90.0 mmol of DMAc obtained per mmol of PdCl2 employed under mild reaction conditions. The influence of reaction parameters such as catalyst precursor dosage, ligand type and promoter on activity is investigated. This work also discusses in detail the halide promoter's role in the reaction, and provides a plausible mechanism based on the intermediates methyl iodide and acetyl iodide. Analyses indicate that the carbonylation of trimethylamine may proceed through an active intermediate acetyl iodide formed by carbonylation of methyl iodide generated from the decomposition of the promoter Me4NI under reaction conditions. The formation of acetyl iodide favors the cleaving efficiency of the inert unstrained C(sp3)―N bond of trimethylamine. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
994.
995.
An excellent asymmetric synthesis of both (R) and (S)-α-substituted benzylamines in optical purity 90.4–99.9% has been achieved by alkylation of a chiral ketimine, prepared from pinanone and benzylamine. Diastereoselectivity in the alkylation is not dependent on the alkyl halides. 相似文献
996.
997.
In this paper, we present some new perturbation bounds for the orthogonal projections onto the column and row spaces of a matrix, which improve some existing results. Numerical examples are presented to illustrate our results. 相似文献
998.
Li-Miao Lin Yong-Hang Xu Man Shen Jia-Xin Liang Shuan-Jin Wang Min Xiao Yue-Zhong Meng 《高分子科学》2021,39(3):337-343
A series of semi-aromatic polyesters named as Poly(PO-CHO-PA) were facilely synthesized via ring-opening terpolymerization of biobased cyclohexane oxide(CHO)/propylene oxide(PO)/phthalic anhydride(PA) using economical U1/PPNCl as dual catalyst. The proportion of CHO-PA and PO-PA segments in polymer can be readily altered by changing the feed ratio of CHO/PO because the reactivity ratios of CHO and PO with PA calculated by Fineman-Ross method are comparable. All synthesized amorphous polyesters with various compositions show one Tg ranging from 62 ℃ to 133 ℃. Significantly, the mechanical, thermal and barrier properties of these amorphous semi-aromatic polyesters are also adjustable and investigated for the first time. The results indicate the semi-polyesters exhibit superior thermostability(T5% ranging from 306 ℃ to323 ℃) and high tensile strength(40.21-55.7 MPa) that is comparable with polystyrene(PS). Furthermore, Poly(PO-CHO-PA) films possess a promising prospect as packaging materials because of its colorless and highly transparent nature, along with low oxygen and water vapor transmission rate. All above performances may guarantee its potential alternative to commercial PS. 相似文献
999.
Wu Bin Lyu Pin Wang Kaixuan Qiu Xiaoyan Liu Taifeng Zhang Fang Li Hexing Xiao Shengxiong 《Research on Chemical Intermediates》2018,44(10):6327-6337
Research on Chemical Intermediates - Upon oxidation, a graphyne-like porous carbon-rich network (GYLPC), which is a two-dimensional carbon material consisting of sp- and sp2-hybridized carbon atoms... 相似文献
1000.
The enhanced biological activities of three Zn (II) complexes based on different 1,2,4‐triazole fungicides 下载免费PDF全文
Guo‐yu Ren Jie Li Xu‐zhan Wei Jin‐hua Zhou Biao Yan Zhao‐qi Guo Ying‐hui Ren Xiao‐hong Sun Hai‐xia Ma 《应用有机金属化学》2018,32(9)
In order to screen effective fungicides, three Zn (II) complexes, [Zn L 1 4 (NO3)2]·2H2O·2EtOH ( 1 ), [Zn L 2 4 (NO3)2] ( 2 ), and [Zn L 3 4 (DMF)2](NO3)2 ( 3 ), ( L 1 = paclobutrazol, L 2 = diniconazole, and L 3 = hexaconazole), were synthesized and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all the complexes show the enhanced antifungal activities than the corresponding ligand and mixtures. And, the interactions between the metal salt and ligands in the three complexes seem to be synergistic. According to the study of the influence of the structures on the activity, complex 2 with C=C linkage and 2,4‐dichlorophenyl moieties enhances the bioactivity significantly, especially against Wheat gibberellic ( II ). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity of the Zn (II) complexes. Meanwhile, all complexes are excellent grow‐regulators, especially complex 3 . The resulting data show that the complexes based on triazole fungicides have the potential applications in agriculture. 相似文献