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891.
Chao Wang Jiafang Piao Yujie Li Xiancheng Tian Yuanchen Dong Dongsheng Liu 《Angewandte Chemie (International ed. in English)》2020,59(35):15176-15180
The shape of eukaryotic cells is determined by the cytoskeleton associated with membrane proteins; however, the detailed mechanism of how the integral morphologies with structural stability is generated and maintained is still not fully understood. Here, based on the Frame‐Guided Assembly (FGA) strategy, we successfully prepared hetero‐liposomes with structural composition similar to that of eukaryotic cells by screening a series of transmembrane peptides as the leading hydrophobic groups (LHGs). It was demonstrated that the conformation and transmembrane mode of the LHGs played dominant roles during the FGA process. The FGA liposomes were formed with excellent stability, which may further provide evidence for the cytoskeleton–membrane protein–lipid bilayer model. Taking advantage of the biocompatibility and stability, the FGA liposomes were also applied to prepare novel drug delivery vehicles, which is promising in diagnostic imaging and cancer therapy applications. 相似文献
892.
Nan Wang Xiaoli Dong Bingliang Wang Zhaowei Guo Zhuo Wang Renhe Wang Xuan Qiu Yonggang Wang 《Angewandte Chemie (International ed. in English)》2020,59(34):14577-14583
Aqueous zinc (Zn) batteries have been considered as promising candidates for grid‐scale energy storage. However, their cycle stability is generally limited by the structure collapse of cathode materials and dendrite formation coupled with undesired hydrogen evolution on the Zn anode. Herein we propose a zinc–organic battery with a phenanthrenequinone macrocyclic trimer (PQ‐MCT) cathode, a zinc‐foil anode, and a non‐aqueous electrolyte of a N,N‐dimethylformamide (DMF) solution containing Zn2+. The non‐aqueous nature of the system and the formation of a Zn2+–DMF complex can efficiently eliminate undesired hydrogen evolution and dendrite growth on the Zn anode, respectively. Furthermore, the organic cathode can store Zn2+ ions through a reversible coordination reaction with fast kinetics. Therefore, this battery can be cycled 20 000 times with negligible capacity fading. Surprisingly, this battery can even be operated in a wide temperature range from ?70 to 150 °C. 相似文献
893.
Kai Chen Gang Huang Jin‐Ling Ma Jin Wang Dong‐Yue Yang Xiao‐Yang Yang Yue Yu Xin‐Bo Zhang 《Angewandte Chemie (International ed. in English)》2020,59(38):16661-16667
The lithium (Li)–air battery has an ultrahigh theoretical specific energy, however, even in pure oxygen (O2), the vulnerability of conventional organic electrolytes and carbon cathodes towards reaction intermediates, especially O2?, and corrosive oxidation and crack/pulverization of Li metal anode lead to poor cycling stability of the Li‐air battery. Even worse, the water and/or CO2 in air bring parasitic reactions and safety issues. Therefore, applying such systems in open‐air environment is challenging. Herein, contrary to previous assertions, we have found that CO2 can improve the stability of both anode and electrolyte, and a high‐performance rechargeable Li–O2/CO2 battery is developed. The CO2 not only facilitates the in situ formation of a passivated protective Li2CO3 film on the Li anode, but also restrains side reactions involving electrolyte and cathode by capturing O2?. Moreover, the Pd/CNT catalyst in the cathode can extend the battery lifespan by effectively tuning the product morphology and catalyzing the decomposition of Li2CO3. The Li–O2/CO2 battery achieves a full discharge capacity of 6628 mAh g?1 and a long life of 715 cycles, which is even better than those of pure Li–O2 batteries. 相似文献
894.
Hai‐Dong Xia Zhong‐Liang Li Qiang‐Shuai Gu Xiao‐Yang Dong Jia‐Heng Fang Xuan‐Yi Du Li‐Lei Wang Xin‐Yuan Liu 《Angewandte Chemie (International ed. in English)》2020,59(39):16926-16932
We describe a photoinduced copper‐catalyzed asymmetric radical decarboxylative alkynylation of bench‐stable N‐hydroxyphthalimide(NHP)‐type esters of racemic alkyl carboxylic acids with terminal alkynes, which provides a flexible platform for the construction of chiral C(sp3)?C(sp) bonds. Critical to the success of this process are not only the use of the copper catalyst as a dual photo‐ and cross‐coupling catalyst but also tuning of the NHP‐type esters to inhibit the facile homodimerization of the alkyl radical and terminal alkyne, respectively. Owing to the use of stable and easily available NHP‐type esters, the reaction features a broader substrate scope compared with reactions using the alkyl halide counterparts, covering (hetero)benzyl‐, allyl‐, and aminocarbonyl‐substituted carboxylic acid derivatives, and (hetero)aryl and alkyl as well as silyl alkynes, thus providing a vital complementary approach to the previously reported method. 相似文献
895.
Chen Sun Ya‐Hui Guo Sha‐Sha Han Jing‐Zhao Li Kuan Jiang Lin‐Feng Dong Qi‐Long Liu Cheng‐Yang Yue Xiao‐Wu Lei 《Angewandte Chemie (International ed. in English)》2020,59(38):16465-16469
Considering the instability and low photoluminescence quantum yield (PLQY) of blue‐emitting perovskites, it is still challenging and attractive to construct single crystalline hybrid lead halides with highly stable and efficient blue light emission. Herein, by rationally introducing d10 transition metal into single lead halide as new structural building unit and optical emitting center, we prepared a bimetallic halide of [(NH4)2]CuPbBr5 with new type of three‐dimensional (3D) anionic framework. [(NH4)2]CuPbBr5 exhibits strong band‐edge blue emission (441 nm) with a high PLQY of 32 % upon excitation with UV light. Detailed photophysical studies indicate [(NH4)2]CuPbBr5 also displays broadband red light emissions derived from self‐trapped states. Furthermore, the 3D framework features high structural and optical stabilities at extreme environments during at least three years. To our best knowledge, this work represents the first 3D non‐perovskite bimetallic halide with highly efficient and stable blue light emission. 相似文献
896.
Du Min Zhang Feng Zhang Xiaofei Dong Wentao Sang Yuanhua Wang Jianjun Liu Hong Wang Shuhua 《中国科学:化学(英文版)》2020,63(12):1767-1776
Science China Chemistry - Rechargeable aqueous zinc ion batteries (ZIBs), with the easy operation, cost effectiveness, and high safety, are emerging candidates for high-energy wearable/portable... 相似文献
897.
Xing‐Cai Huang Jia‐Xin Li Yong‐Zhi Chen Wen‐Yan Wang Rui Xu Jin‐Xia Tao Dong Shao Yi‐Quan Zhang 《化学:亚洲杂志》2020,15(9):1469-1477
Tuning the magnetic anisotropy of metal ions remains highly interesting in the design of improved single‐molecule magnets (SMMs). We herein report synthetic, structural, magnetic, and computational studies of four mononuclear CoII complexes, namely [Co(hfac)2(MeCN)2] ( 1 ), [Co(hfac)2(Spy)2] ( 2 ), [Co(hfac)2(MBIm)2] ( 3 ), and [Co(hfac)2(DMF)2] ( 4 ) (MeCN=acetonitrile, hfac=hexafluoroacetylacetone, Spy=4‐styrylpyridine, MbIm=5,6‐dimethylbenzimidazole, DMF=N,N‐dimethylformamide), with distorted octahedral geometry constructed from hexafluoroacetylacetone (hfac) and various axial ligands. By a building block approach, complexes 2 – 4 were synthesized by recrystallization of the starting material of 1 from various ligands containing solution. Magnetic and theoretical studies reveal that 1 – 4 possess large positive D values and relative small E parameters, indicating easy‐plane magnetic anisotropy with significant rhombic anisotropy in 1 – 4 . Dynamic alternative current (ac) magnetic susceptibility measurements indicate that these complexes exhibit slow magnetic relaxation under external fields, suggesting field‐induced single‐ion magnets (SIMs) of 1 – 4 . These results provide a promising platform to achieve fine tuning of magnetic anisotropy through varying the axial ligands based on Co(II) bis(hexafluoroacetylacetonate) complexes. 相似文献
898.
Chen Sun Wen‐Li He Mei‐Jun Liu Wen‐Jing Pan Lin‐Feng Dong Guang Chen Guo‐Dong Liu Xiao‐Wu Lei 《化学:亚洲杂志》2020,15(19):3050-3058
Recently, low‐dimensional organic‐inorganic hybrid metal halide perovskites acting as single‐component white‐light emitting materials have attracted extensive attention, but most studies concentrate on hybrid lead perovskites. Herein, we present two isomorphic zero‐dimensional (0D) hybrid cadmium perovskites, (HMEDA)CdX4 (HMEDA=hexamethylenediamine, X=Cl ( 1 ), Br ( 2 )), which contain isolated [CdX4]2? anions separated by [HMEDA]2+ cations. Under UV light excitation, both compounds display broadband bluish white‐light emission (515 nm for 1 and 445 nm for 2 ) covering the entire visible light spectrum with sufficient photophysical stabilities. Remarkably, compound 2 shows a high color rendering index (CRI) of 83 enabling it as a promising candidate for single‐component WLED applications. Based on the temperature‐dependent, powder‐dependent and time‐resolved PL measurements as well as other detailed studies, the broadband light emissions are attributed to self‐trapped excitons stemming from the strong electron‐phonon coupling. 相似文献
899.
Dong Yang Pei Liu Wanran Lin Shanglin Sui Long‐Biao Huang Ben Bin Xu Jie Kong 《化学:亚洲杂志》2020,15(16):2499-2504
Hyperbranched polymers have garnered much attention due to attractive properties and wide applications, such as drug‐controlled release, stimuli‐responsive nano‐objects, photosensitive materials and catalysts. Herein, two types of novel hyperbranched poly(ester‐enamine) (hb‐PEEa) were designed and synthesized via the spontaneous amino‐yne click reaction of A2 monomer (1, 3‐bis(4‐piperidyl)‐propane (A2a) or piperazine (A2b)) and B3 monomer (trimethylolpropanetripropiolate). According to Flory's hypothesis, gelation is an intrinsic problem in an ideal A2+B3 polymerization system. By controlling the polymerization conditions, such as monomer concentration, molar ratio and rate of addition, a non‐ideal A2+B3 polymerization system can be established to avoid gelation and to synthesize soluble hb‐PEEa. Due to abundant unreacted alkynyl groups in periphery, the hb‐PEEa can be further functionalized by different amino compounds or their derivates. The as‐prepared amphiphilic PEG‐hb‐PEEa copolymer can readily self‐assemble into micelles in water, which can be used as surfactant to stabilize Au nanoparticles (AuNPs) during reduction of NaBH4 in aqueous solution. As a demonstration, the as‐prepared PEG‐hb‐PEEa‐supported AuNPs demonstrate good dispersion in water, solvent stability and remarkable catalytic activity for reduction of nitrobenzene compounds. 相似文献
900.
Sim Woojeong Lee Booyeong Kim Dong Ju Lee Jeong A Kim Jaewon Chung Jintai 《Nonlinear dynamics》2022,108(2):987-1004
Nonlinear Dynamics - This study analyzes the vibro-impact behavior of two adjacent cantilever beams subjected to vibration generated by applying harmonic excitation to their rigid base. For the... 相似文献