Comprehensive Summary A design strategy towards stable fluorenyl radicals(FRs)has been developed through introducing donor-π-radical(D-π-R)conjugation,facilitated by the linkage of amine N atoms and FR centers via p...Comprehensive Summary A design strategy towards stable fluorenyl radicals(FRs)has been developed through introducing donor-π-radical(D-π-R)conjugation,facilitated by the linkage of amine N atoms and FR centers via phenyl or 9-anthryl moieties.Four FRs,with or without N atom containing protecting groups,were designed and synthesized for comparative analysis.展开更多
Kaschin-Beck disease (KBD) could be exogeneous free radical induced endemic osteoarthropathy under conditions of lacking necessary antioxidant defences.especially selenium-cored defence in Chinese eco-en-vironment. Ex...Kaschin-Beck disease (KBD) could be exogeneous free radical induced endemic osteoarthropathy under conditions of lacking necessary antioxidant defences.especially selenium-cored defence in Chinese eco-en-vironment. Experimental evidences have been provided for the internal relations among previously suggested pathologic factors, i.e., selenium deficiency, organic matters of drinking waterand mycotoxins from contaminated grains, based on the facts that the former is a preventory factor while the others are exogenous freeradical carriers. ESR spectrum shows that these exogenous free radical carriers have a property of semi-quinone compounds and are toxic in in-vitro cartilage cell culture and animal tests in inducing lipid peroxidation process.展开更多
Metal nanoclusters have shown great potential in photocatalysis,while simultaneous removal of both inorganic and organic contaminants by metal nanoclusters under visible light is less explored.Here,we synthesized Agm(...Metal nanoclusters have shown great potential in photocatalysis,while simultaneous removal of both inorganic and organic contaminants by metal nanoclusters under visible light is less explored.Here,we synthesized Agm(SR)n(SR represents 3-mercaptopropyltriethoxysilane ligand) nanoclusters(~1 nm) via a reduction of silver triphenylphosphine under ambient conditions in the presence of 3-mercaptopropyltriethoxysilane.The nanocluster was characterized by UV-vis spectroscopy,high resolution transmission electron microscopy(HRTEM),Fourier transform infrared spectrum(FTIR),and X-ray photoelectron spectroscopy(XPS).Under 5 W blue LED,the Agm(SR)n/P25 exhibits enhanced catalytic activity for simultaneous methyl orange(MO) oxidation and Cr(Ⅵ) reduction,and also for synchronous 4-chlorophenol oxidation and Cr(Ⅵ) reduction.Mechanism studies by electrochemical impedance spectroscopy(EIS),photoluminescence(PL),electron spin resonance(ESR) etc.and control experiments reveal that the unique structure of silver nanoclusters with thiolate ligands is vital to the high catalytic performance,and both the photo-generated holes and superoxide radicals are responsible for the decomposition of MO.展开更多
The direct C(sp^(2))-H bond alkylation of maleimides using iminophosphorane-induced Fe(III)-catalyzed HAT(hydrogen atom transfer)strategy was achieved,and a series of novel alkyl maleimide derivatives were synthesized...The direct C(sp^(2))-H bond alkylation of maleimides using iminophosphorane-induced Fe(III)-catalyzed HAT(hydrogen atom transfer)strategy was achieved,and a series of novel alkyl maleimide derivatives were synthesized.The reaction has the characteristics of mild conditions,widespread functional group compatibility and substrates adaptability.The mechanism study shows that it mainly involves MHAT(metal-catalyzed hydrogen atom transfer),radical conjugate addition,SET(single electron transfer)processes,and theoretical calculations reveal that the critical step is that phosphorus radical intermediate G is converted to phosphorus cationic intermediate I.The research provides a new insight into the direct functionalization of C(sp^(2))-H to form C(sp^(2))-C(sp^(3))bonds via the HAT strategy.展开更多
For an ordered field (K,T) and an idealI of the polynomial ring $K\left[ {x_1 , \cdots ,x_n } \right]$ , the construction of the generalized real radical $^{\left( {T,U,W} \right)} \sqrt I $ ofI is investigated. When ...For an ordered field (K,T) and an idealI of the polynomial ring $K\left[ {x_1 , \cdots ,x_n } \right]$ , the construction of the generalized real radical $^{\left( {T,U,W} \right)} \sqrt I $ ofI is investigated. When (K,T) satisfies some computational requirements, a method of computing $^{\left( {T,U,W} \right)} \sqrt I $ is presented.展开更多
基金supported by Natural Science Foundation of China(22175128)starting grants of Tianjin University.
文摘Comprehensive Summary A design strategy towards stable fluorenyl radicals(FRs)has been developed through introducing donor-π-radical(D-π-R)conjugation,facilitated by the linkage of amine N atoms and FR centers via phenyl or 9-anthryl moieties.Four FRs,with or without N atom containing protecting groups,were designed and synthesized for comparative analysis.
文摘Kaschin-Beck disease (KBD) could be exogeneous free radical induced endemic osteoarthropathy under conditions of lacking necessary antioxidant defences.especially selenium-cored defence in Chinese eco-en-vironment. Experimental evidences have been provided for the internal relations among previously suggested pathologic factors, i.e., selenium deficiency, organic matters of drinking waterand mycotoxins from contaminated grains, based on the facts that the former is a preventory factor while the others are exogenous freeradical carriers. ESR spectrum shows that these exogenous free radical carriers have a property of semi-quinone compounds and are toxic in in-vitro cartilage cell culture and animal tests in inducing lipid peroxidation process.
基金the National Natural Science Foundation of China (No.21671176)。
文摘Metal nanoclusters have shown great potential in photocatalysis,while simultaneous removal of both inorganic and organic contaminants by metal nanoclusters under visible light is less explored.Here,we synthesized Agm(SR)n(SR represents 3-mercaptopropyltriethoxysilane ligand) nanoclusters(~1 nm) via a reduction of silver triphenylphosphine under ambient conditions in the presence of 3-mercaptopropyltriethoxysilane.The nanocluster was characterized by UV-vis spectroscopy,high resolution transmission electron microscopy(HRTEM),Fourier transform infrared spectrum(FTIR),and X-ray photoelectron spectroscopy(XPS).Under 5 W blue LED,the Agm(SR)n/P25 exhibits enhanced catalytic activity for simultaneous methyl orange(MO) oxidation and Cr(Ⅵ) reduction,and also for synchronous 4-chlorophenol oxidation and Cr(Ⅵ) reduction.Mechanism studies by electrochemical impedance spectroscopy(EIS),photoluminescence(PL),electron spin resonance(ESR) etc.and control experiments reveal that the unique structure of silver nanoclusters with thiolate ligands is vital to the high catalytic performance,and both the photo-generated holes and superoxide radicals are responsible for the decomposition of MO.
基金support by the Opening Project of Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan(No.LYJ2405).
文摘The direct C(sp^(2))-H bond alkylation of maleimides using iminophosphorane-induced Fe(III)-catalyzed HAT(hydrogen atom transfer)strategy was achieved,and a series of novel alkyl maleimide derivatives were synthesized.The reaction has the characteristics of mild conditions,widespread functional group compatibility and substrates adaptability.The mechanism study shows that it mainly involves MHAT(metal-catalyzed hydrogen atom transfer),radical conjugate addition,SET(single electron transfer)processes,and theoretical calculations reveal that the critical step is that phosphorus radical intermediate G is converted to phosphorus cationic intermediate I.The research provides a new insight into the direct functionalization of C(sp^(2))-H to form C(sp^(2))-C(sp^(3))bonds via the HAT strategy.
基金Project supported by the National Natural Science Foundation of China (Grant No. 19661002)the Climbing Project
文摘For an ordered field (K,T) and an idealI of the polynomial ring $K\left[ {x_1 , \cdots ,x_n } \right]$ , the construction of the generalized real radical $^{\left( {T,U,W} \right)} \sqrt I $ ofI is investigated. When (K,T) satisfies some computational requirements, a method of computing $^{\left( {T,U,W} \right)} \sqrt I $ is presented.
