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881.
882.
Jin Jie Tian Xu Tao Yi Kou Xianli Mi Yuanhao Xu Xiaokang Yang Huifeng 《Journal of Solid State Electrochemistry》2023,27(9):2309-2321
Journal of Solid State Electrochemistry - CrMoCN coatings with different carbon contents are prepared on 316L stainless steel substrates by closed-field unbalanced magnetron sputtering. The... 相似文献
883.
Dr. Yu Rao Prof. Zongkui Kou Prof. Xianghua Zhang Prof. Ping Lu 《Chemical record (New York, N.Y.)》2023,23(6):e202200251
Metal organic framework (MOF) glasses are a coordination network of metal nodes and organic ligands as an undercooled frozen-in liquid, and have therefore broadened the potential of MOF materials in the fundamental research and application scenarios. On the road to deploying MOF glasses as electrocatalysts, it remains several basic scientific hurdles although MOF glasses not only inherit the structural merits of MOFs but also endow with active catalytic features including concentrated defects, metal centers and disorder structure etc. The research on the ionic conductivity, catalytic stability and reactivity of MOF glasses has yielded scientific insights towards its electrocatalytic applications. Here, we first comb the history, definition and basic properties of MOF glasses. Then, we identify the main synthetic methods and characterization techniques. Finally, we advance the potentials and challenges of MOF glasses as electrocatalysts in furthering the understanding of these themes. 相似文献
884.
Yukun Ma Xiaoxia You Dr. Jinbo Zhang Dr. Xiaowu Wang Dr. Xinhui Kou Prof. Dr. Shaofeng Liu Prof. Dr. Ronglin Zhong Prof. Dr. Zhibo Li 《Angewandte Chemie (International ed. in English)》2023,62(25):e202303315
Chemoselective terpolymerization can produce polymer materials with diverse compositions and sequential structures, and thus have attracted considerable attention in the field of polymer synthesis. However, the intrinsic complexity of three-component system also brings great chanllenge, in regard to the reactivity and selectivity of different monomers. Herein, we report the terpolymerization of CO2/epoxide/anhydride by a binary organocatalytic C3N3-Py-P3/TEB (triethylborane) system. Both the activity and chemoselectivity were highly dependent upon the molar ratio of C3N3-Py-P3 to TEB, and sequence-controlled poly(ester-carbonate) copolymers were readily synthesized through one-pot/one-step methodology by tuning the stoichiometric ratio of phosphazene/TEB. In particular, C3N3-Py-P3/TEB with a molar ratio of 1/0.5 exhibited an unprecedentedly high chemoselectivity for ring-opening alternating copolymerization (ROAC) of cyclohexene oxide (CHO) and phthalic anhydride (PA) first and then ROAC of CO2/CHO. Thus, well-defined triblock polycarbonate-b-polyester-b-polycarbonate copolymers can be produced from the mixture of CO2, CHO and PA using a bifunctional initiator. With C3N3-Py-P3/TEB=1/1, tapered copolymers were obtained, while random copolymers with high content of polycarbonate (PC) were synthesized with further increasing the amount of TEB. The mechanism of the unexpected chemoselectivity was further investigated by DFT calculations. 相似文献
885.
Hao K. Shen Kiyoshi Morishita Dr. P. K. Hashim Prof. Dr. Kou Okuro Daiki Kashiwagi Ayumi Kimura Dr. Haruaki Yanagisawa Prof. Dr. Masahide Kikkawa Prof. Dr. Tatsuya Niwa Prof. Dr. Hideki Taguchi Prof. Dr. Takuzo Aida 《Angewandte Chemie (International ed. in English)》2023,62(31):e202304894
Herein, we report an ATP-responsive nanoparticle (GroELNP) whose surface is fully covered with the biomolecular machine “chaperonin protein GroEL”. GroELNP was synthesized by DNA hybridization between a gold NP with DNA strands on its surface and GroEL carrying complementary DNA strands at its apical domains. The unique structure of GroELNP was visualized by transmission electron microscopy including under cryogenic conditions. The immobilized GroEL units retain their machine-like function and enable GroELNP to capture denatured green fluorescent protein and release it in response to ATP. Interestingly, the ATPase activity of GroELNP per GroEL was 4.8 and 4.0 times greater than those of precursor cysGroEL and its DNA-functionalized analogue, respectively. Finally, we confirmed that GroELNP could be iteratively extended to double-layered NP. 相似文献
886.
Dr. Fan Yang Dr. Ting Geng Prof. Hang Shen Yan Kou Prof. Guanjun Xiao Prof. Bo Zou Prof. Yulan Chen 《Angewandte Chemie (International ed. in English)》2023,62(39):e202308662
Optical force probes that can release force-dependent and visualized signals with minimal changes in the polymer main chains under mechanical load are highly sought after but currently limited. In this study, we introduce a flex-activated mechanophore (FA) based on the Diels–Alder adduct of anthracene and dimethyl acetylenedicarboxylatea that exhibits turn-on mechanofluorescence. We demonstrate that when FA is incorporated into polymer networks or in its crystalline state, it can release fluorescent anthracenes through a retro-Diels–Alder mechanochemical reaction under compression or hydrostatic high pressure, respectively. The flex-activated mechanism of FA is successfully confirmed. Furthermore, we systematically modulate the force delivered to the mechanophore by varying the crosslinking density of the networks and the applied macroscopic pressures. This modulation leads to incremental increases in mechanophore activation, successive release of anthracenes, and quantitative enhancement of fluorescence intensity. The exceptional potential of FA as a sensitive force probe in different bulk states is highlighted, benefiting from its unique flex-activated mode with highly emissive fluorophore releasing. Overall, this report enriches our understanding of the structures and functions of flex-activated mechanophores and polymeric materials. 相似文献
887.
Yan Jiewen Pan Jisheng Yan Qiusheng Zhou Rui Wu Yusen 《Journal of Solid State Electrochemistry》2023,27(3):597-610
Journal of Solid State Electrochemistry - Electrochemical magnetorheological finishing (EC–MRF) is an ultrasmooth planarization method that etches a workpiece surface with a controllable... 相似文献
888.
Wu Yusen Pan Jisheng Wang Hao Shen Zhuoshan Luan Tianxin Yan Qiusheng 《Journal of Solid State Electrochemistry》2023,27(8):2163-2176
Journal of Solid State Electrochemistry - A magnetorheological electro-Fenton composite polishing technology was proposed that enables chemical and mechanical “double enhancement” of... 相似文献
889.
Han Chengdong Kou Wei Wang Rong Chen Xurong 《The European Physical Journal A - Hadrons and Nuclei》2023,59(5):1-11
The European Physical Journal A - Initially, yields (or abundances) and branching ratios of β-delayed neutrons (βdn) from fission products (Pn-values) have had their main importance in... 相似文献