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951.
952.
Shuo Huang Jiacai Zhu Prof. Jinlei Tian Prof. Zhiqiang Niu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14480-14494
Rechargeable aqueous zinc-ion batteries (ZIBs) have garnered tremendous attention in the field of next energy storage devices due to their high safety, low cost, abundant resources, and eco-friendliness. As an important component of the zinc-ion battery, the electrolyte plays a vital role in the electrochemical properties, since it will provide a pathway for the migrations of the zinc ions between the cathode and anode, and determine the ionic conductivity, electrochemically stable potential window, and reaction mechanism. In this Minireview, a brief introduction of electrochemical principles of the aqueous ZIBs is discussed and the recent advances of various aqueous electrolytes for ZIBs, including liquid, gel, and multifunctional hydrogel electrolytes are also summarized. Furthermore, the remaining challenges and future directions of electrolytes in aqueous ZIBs are also discussed, which could provide clues for the following development. 相似文献
953.
Jian Wang Jinjin Zhou Yu Xu Bingqi Zhu Huiyi Li 《Rapid communications in mass spectrometry : RCM》2019,33(17):1410-1419
954.
A facile and efficient method has been developed for synthesis of β-iodocarboxylates in the presences of Ph3P/I2. Starting from epoxides, a series of β-iodocarboxylate compounds can be directly obtained in toluene media with excellent yields. Moreover, the method was successfully applied for the late-stage modification of natural products, such as isosteviol and vincamine derivatives, achieving the corresponding β-iodocarboxylates in good yields. 相似文献
955.
Lin-Lin Zhang Bing-Chao Da Shao-Hua Xiang Shuai Zhu Zi-Yun Yuan Zhen Guo Bin Tan 《Tetrahedron》2019,75(12):1689-1696
Quinones, precursors of aromatic structures, were firstly employed as the electrophiles for the organocatalytic Michael addition/cyclization cascade reaction with versatile 3-isothiocyanato oxindoles. Chiral bifunctional organocatalyst was appropriate for this enantioselective transformation to afford a variety of novel spirooxindoles, possessing a spirocyclic stereocenter adjacent to the aromatic ring, via asymmetric double arylation. These synthesized spirooxindoles are very difficult to access by the reported methods and were obtained in excellent chemical yields with excellent enantioselectivities. 相似文献
956.
Six mono/double‐layered 2D and three 3D coordination polymers were synthesized by a self‐assembly reaction of Zn (II) salts, organic dicarboxylic acids and L1/L2 ligands. These polymeric formulas are named as [Zn(L1)(C4H2O4)0.5 (H2O)]n·0.5n(C4H2O4)·2nH2O ( 1 ), [Zn2(L2)(C4H2O4)2]n·2nH2O ( 2 ), [Zn(L1)(m‐BDC)]n ( 3 ), [Zn2(L2)(m‐BDC)2]n·2nH2O ( 4 ), [Zn3(L1)2(p‐BDC)3(H2O)4]n·2nH2O ( 5 ), [Zn2(OH)(L2) (p‐BDC)1.5]n ( 6 ), [Zn2(L1)(p‐BDC)2]n·5nH2O ( 7 ), [Zn2(L2)(p‐BDC)2]n·3nH2O ( 8 ) and [Zn2(L1)(C4H4O4)1.5(H2O)]n·n(ClO4)·nH2O ( 9 ) [L1 = N,N′‐bis (pyridin‐4‐ylmethyl)propane‐1,2‐diamine, L2 = N,N′‐bis (pyridin‐3‐ylmethyl)propane‐1,2‐ diamine, m‐BDC2? = m‐benzene dicarboxylate, p‐BDC2? = p‐benzene dicarboxylate]. Meanwhile, these polymers have been characterized by elemental analysis, infrared, thermogravimetry (TG), photoluminescence, powder and single‐crystal X‐ray diffraction. Polymers 1–6 present mono‐ and double (4,4)‐layer motifs accomplished by L1/L2 ligands with diverse conformations and organic dicarboxylates, and the layer thickness locates in the range of 5.8–15.0 Å. In three 3D polymers, the L1 and L2 molecules adopt the same cis‐conformations and join adjacent Zn (II) cations together with p‐BDC2? or succinate, giving rise to different binodal (4,4)‐c nets with (4.52.83)(4.53.72) ( 7 ), pts ( 8 ) topology and twofold interpenetrated binodal (5,5)‐c nets with (32.44.52.62)(3.43.52.64) ( 9 ). Therefore, the diverse conformations of the two bis (pyridyl)‐propane‐1,2‐diamines and the feature of different organic dicarboxylate can effectively influence the architectures of these polymers. Powder X‐ray diffraction patterns demonstrate that these bulk solid polymers are pure phase. TG analyses indicate that these polymers have certain thermal stability. Luminescent investigation reveals that the emission maximum of these polymers varies from 402 to 449 nm in the solid state at room temperature. Moreover, 1 , 3 and 5–8 show average luminescence lifetimes from 8.81 to 16.30 ns. 相似文献
957.
Let be a finite field and a positive integer. In this paper, we find a new combinatorial method to determine weight enumerators of reducible cyclic codes and their dual codes of length over , which just generalize results of Zhu et al. (2015); especially, we also give the weight enumerator of a cyclic code, which is viewed as a partial Melas code. Furthermore, weight enumerators obtained in this paper are all in the form of power of a polynomial. 相似文献
958.
International Journal of Theoretical Physics - We propose the scheme for cyclic controlled symmetry quantum teleportation by using one three-dimensional hyper-entangled state as the quantum... 相似文献
959.
Xiong Sun Dr. Wei Su Kaiying Shi Zhuoyi Xie Prof. Dr. Congqing Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(24):5354-5359
Rare-earth metal cations have been used rarely as Lewis-acidic components in the chemistry of frustrated Lewis pairs (FLPs). Herein, we report the first cerium/phosphorus system ( 2 ) employing a heptadentate N4P3 ligand, which exhibits triple FLP-type reactivity towards a series of organic substrates, including isocyanates, isothiocyanates, diazomethane, and azides on a single rare-earth Lewis acidic Ce center. This result shows that the Ce center and three P atoms in 2 could simultaneously activate three equivalents of small molecules under mild conditions. This study broadens the diversity of FLPs and demonstrates that rare earth based FLP exhibit unique properties compared with other FLP systems. 相似文献
960.