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981.
Xuejiao Hu Tiancheng Li Yidan Tang Yirong Wang Dr. Ao Wang Dr. Gengtao Fu Prof. Xiaodong Li Prof. Yawen Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(31):7561-7568
The development of high-efficiency electrocatalysts with low costs for the oxygen evolution reaction (OER) is essential, but remains challenging. Herein, a new synthetic process is proposed to prepare Ni3S4 particles embedded in N,P-codoped honeycomb porous carbon aerogels (Ni3S4/N,P-HPC) through a hydrogel approach. The preparation of Ni3S4/N,P-HPC begins with the sol–gel polymerization of tripolyphosphate, chitosan, and guanidine polymer that contains metal-binding sites, allowing for the uniform incorporation of Ni ions into the gel matrix, freeze-drying, and subsequent carbonization under an inert atmosphere. This synthesis resolves difficulties in synthesizing the pure Ni3S4 phase caused by the instability of Ni3S4 at high temperature, while affording good control of the porous structure and N,P-doping of carbon aerogels. The synergy between the structural advantages of N,P-carbon aerogels (such as easily accessible active sites, high specific surface area, and excellent electron transport) and the intrinsic electrochemical properties of Ni3S4 result in the outstanding OER performance of Ni3S4/N,P-HPC, with overpotentials as low as 0.37 V at 10 mA cm−2. The work outlined herein offers a simple and effective method for the development of carbon-based electrocatalysts for renewable energy conversion. 相似文献
982.
Qianxi Dang Lanzhen Hu Jiaqiang Wang Qunhua Zhang Mengmeng Han Simeng Luo Yanbin Gong Can Wang Prof. Qianqian Li Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):7031-7037
Organic luminescence with different forms continues to be one of the most active research fields in science and technology. Herein, an ultra-simple organic molecule (TPA-B), which exhibits both mechanoluminescence (ML) and photo-induced room-temperature phosphorescence (RTP) in the crystalline state, provides an opportunity to reveal the internal mechanism of ML and the dynamic process of photo-induced RTP in the same molecule. Through the detailed investigation of photophysical properties together with crystal structures, the key role of molecular packing and intermolecular interactions was highlighted in the luminescence response by mechanical and light stimulus, affording efficient strategies to design potential smart functional materials with multiple luminescence properties. 相似文献
983.
Junkai Guo Cuiwen Kuang Jian Rong Dr. Lingchun Li Dr. Chuanfa Ni Prof. Dr. Jinbo Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7259-7264
The deoxyfluorination of alcohols is a fundamentally important approach to access alkyl fluorides, and thus the development of shelf-stable, easy-to-handle, fluorine-economical, and highly selective deoxyfluorination reagents is highly desired. This work describes the development of a crystalline compound, N-tosyl-4-chlorobenzenesulfonimidoyl fluoride (SulfoxFluor), as a novel deoxyfluorination reagent that possesses all of the aforementioned merits, which is rare in the arena of deoxyfluorination. Endowed by the multi-dimensional modulating ability of the sulfonimidoyl group, SulfoxFluor is superior to 2-pyridinesulfonyl fluoride (PyFluor) in fluorination rate, and is also superior to perfluorobutanesulfonyl fluoride (PBSF) in fluorine-economy. Its reaction with alcohols not only tolerates a wide range of functionalities including the more sterically hindered alcoholic hydroxyl groups, but also exhibits high fluorination/elimination selectivity. Because SulfoxFluor can be easily prepared from inexpensive materials and can be safely handled without special techniques, it promises to serve as a practical deoxyfluorination reagent for the synthesis of various alkyl fluorides. 相似文献
984.
Tenghao Yin Lei Wu Tonghao Wu Guoyong Mao Guodong Nian Zhe Chen Xiaocheng Hu Peng Wang Yuhai Xiang Honghui Yu Shaoxing Qu Wei Yang 《Journal of Polymer Science.Polymer Physics》2019,57(5):272-280
Conductive hydrogels with ionic compounds possess great potential for the development of soft smart devices. A dielectric scarfskin is typically required for these devices to prevent short circuiting, leading to devices with lower stretchability than the hydrogel. Henceforth, commonly used dielectric materials, such as PDMS and Ecoflex, cannot be largely stretched. Hydrogel devices with ultrastretchability are required to accommodate hostile application environments. Herein, we propose a hydrogel fiber coated with a dielectric layer that can be stretched to over 2000% of its initial length. The fiber remains conductive when stretched to ~1300%. In addition, the core/sheath hydrogel fiber can be endowed with a variety of functional properties, such as electroluminescence (EL), photoluminescence (PL), and magnetic‐responsiveness, demonstrating scalability of the resultant fiber. The present work can pave the way for numerous next‐generation soft devices, such as smart textiles and wearable electronics. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 272–280 相似文献
985.
Jianxian Zeng Zhe Zhang Hu Zhou Guoqing Liu Yuan Liu Lingwei Zeng Jian Jian Zhengqiu Yuan 《先进技术聚合物》2019,30(7):1865-1877
While conventional approaches have been studied for removal of ruthenium(III) ions (Ru(III)), this work focuses on the applicability of ion‐imprinted poly(methyl methacrylate‐vinyl pyrrolidone)/poly(vinylidene fluoride) blending membranes (Ru(III)–ion‐imprinted membrane[IIM]) for selective removal of Ru(III) from acidic water solutions. In order to measure the effectiveness of these imprinted membranes, after fabrication, binding experiments were done with aqueous Ru(III) solutions. The results showed that Ru(III)‐IIMs were fabricated successfully at various blending ratios, and their chemical components, microstructures, hydrophilicity, and water fluxes were measured. In pH range 0.5 to 5.0, binding capacity (Qe) of Ru(III) onto Ru(III)‐IIM increases remarkably with pH and then reaches to a maximum value (53.52 mg/g) at pH 1.5. After that, Qe gradually decreases. Compared with a nonimprinted membrane, Ru(III)‐IIM demonstrates higher selectivity for Ru(III) at pH 1.5 in the presence of Ni(II) and Cu(II) ions, and its selectivity coefficients for Ru(III)/Ni(II) and Ru(III)/Cu(II) are 3.70 and 3.32, respectively. Also, Ru(III)‐IIM shows a good chemical stability and reusability. C─N and C═O bonds within poly(vinyl pyrrolidone) segments of poly(methyl methacrylate‐vinyl pyrrolidone) (P(MMA‐VP)) participate the uptake of Ru(III). Ru(III)‐IIM exhibited excellent hydrophilicity and Ru(III) selective adsorption ability and reusability and has potential to be used for Ru(III) removal from acidic water solutions. 相似文献
986.
Minghui Qi Shiyi Zhao Bin Zhou Min Zhang Hongyang Zhang Yuerong Wang Ping Hu 《Journal of separation science》2019,42(23):3503-3511
Forsythiaside A is the major component of Forsythia suspensa. This study investigated the degradation mechanism of forsythiaside A. Eight degraded components including forsythiaside I, forsythiaside H, forsythiaside E, caffeic acid, suspensaside A, β‐hydroxy forsythiaside I, β‐hydroxy forsythiaside H, and β‐hydroxy forsythiaside A were identified by using ultra‐high performance liquid chromatography quadrupole time‐of‐flight mass spectrometry. Then, the quantitative analysis of multi‐components by a single‐marker was performed with ultra‐high performance liquid chromatography to simultaneously determine forsythiaside A, forsythiaside H, and forsythiaside I in Forsythia suspensa preparations. The result showed good linear relationships within 2.871–287.1, 0.231–23.1, and 0.983–98.3 μg/mL (r > 0.9998), with average recoveries of 97.7, 95.7, and 95.8% and relative standard deviations of 1.4, 2.4, and 1.8%, respectively. Using forsythiaside A as an internal reference, the relative retention values of forsythiaside H and forsythiaside I to forsythiaside A were calculated to be 0.89 and 0.61, respectively, and the relative correction factors were 0.816 and 0.799, respectively. The method for quantitative analysis of multi‐components by a single‐marker was applied to evaluate the overall quality of forsythia preparations. There was no significant difference in the measurement results of the method developed and the method of external standard. 相似文献
987.
Zhaoyang Cheng Shipei Xing Jun Guo Biao Cheng Lan‐Fang Hu Xing‐Hong Zhang Zhan Lu 《中国化学》2019,37(5):457-461
A regioselective double 1,1‐hydrosilylation of terminal aliphatic alkynes with primary silanes catalyzed by one cobalt catalyst has been developed. gem‐Bis(dihydrosilyl)alkanes containing four silicon‐hydrogen bonds are efficiently constructed in an atom‐economical manner. Tolerated substrates include simplest alkyne‐ethyne, a complicated drug derivative and various functionalized terminal aliphatic alkynes. Asymmetric approach using two catalysts is achieved with excellent enantioselectivities to access corresponding chiral products. The transformations of Si—H bonds into Si—C, Si—O, and Si—F bonds and the synthesis of enantioriched α‐hydroxysilane show synthetic utility. 相似文献
988.
Yizhao Ouyang Miao Zhan Jing Zhou Jiao Jiao Hao Hu Yoichi M. A. Yamada Pengfei Li 《中国化学》2019,37(8):807-810
A rigid C2‐symmetric chiral bipyridine ligand Z‐bpy with a triptycene‐like backbone was designed and synthesized from simple chemicals in a scalable route. Using this new ligand, copper(I) catalyzed cyclopropanation of styrenes with commercial ethyl diazoacetate produced various corresponding cyclopropanes in high yields, diastereoselectivity and enantioselectivity up to 97% ee. 相似文献
989.
Cong Hu Bingyang Dong Li Liu 《Journal of polymer science. Part A, Polymer chemistry》2019,57(12):1333-1343
We report on the preparation of reduction‐responsive amphiphilic block copolymers containing pendent p‐nitrobenzyl carbamate (pNBC)‐caged primary amine moieties by reversible addition–fragmentation chain transfer (RAFT) radical polymerization using a poly(ethylene glycol)‐based macro‐RAFT agent. The block copolymers self‐assembled to form micelles or vesicles in water, depending on the length of hydrophobic block. Triggered by a chemical reductant, sodium dithionite, the pNBC moieties decomposed through a cascade 1,6‐elimination and decarboxylation reactions to liberate primary amine groups of the linkages, resulting in the disruption of the assemblies. The reduction sensitivity of assemblies was affected by the length of hydrophobic block and the structure of amino acid‐derived linkers. Using hydrophobic dye Nile red (NR) as a model drug, the polymeric assemblies were used as nanocarriers to evaluate the potential for drug delivery. The NR‐loaded nanoparticles demonstrated a reduction‐triggered release profile. Moreover, the liberation of amine groups converted the reduction‐responsive polymer into a pH‐sensitive polymer with which an accelerated release of NR was observed by simultaneous application of reduction and pH triggers. It is expected that these reduction‐responsive block copolymers can offer a new platform for intracellular drug delivery. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1333–1343 相似文献
990.
Wu Peng Wang Yun Li Yang Hu Xuewen Xiu Taoyuan Yuan Dingzhong Liu Yan Wu Zhenyu Liu Zhirong 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):553-559
Journal of Radioanalytical and Nuclear Chemistry - In order to reduce the potential toxicity to the environment after treatment of radioactive waste water, an eco-friendly graphene oxide... 相似文献