Shaped charge jet formation process is studied under the conditions of different background lights by means of high speed frame photography. In order to shoot true jet appearance, the glass tube in which jet moves is...Shaped charge jet formation process is studied under the conditions of different background lights by means of high speed frame photography. In order to shoot true jet appearance, the glass tube in which jet moves is vacuumized. The experiment results show that observing jet appearance with the double reflecting mirrors system is feasible as long as the vacuum of the glass tube can meet the requirement of experiment.展开更多
To address the dissolution issue and enhance the electrochemical performance of organic electrode materials,herein, a bipolar organic cathode was prepared by in-situ electropolymerization of amino-phenyl carbazole nap...To address the dissolution issue and enhance the electrochemical performance of organic electrode materials,herein, a bipolar organic cathode was prepared by in-situ electropolymerization of amino-phenyl carbazole naphthalene diimide(APCNDI). APCNDI is composed of n-type 1,4,5,8-naphthalene tetracarboxylic diimide that stores Li cations and p-type carbazole groups which react with anions and serve as polymerization sites. Electropolymerization completely eliminated the dissolution problem of APCNDI, and the electropolymerized cathode demonstrated a bipolar reaction with excellent electrochemical performance, stable cycling performance with a capacity retention of 92 mA h g;after1000 cycles, and a superior rate performance of 72 mA h g;at 10 A g;. The bipolar feature and reactions of APCNDI were systematically investigated and verified by multiple characterization techniques. Our findings provide a novel strategy for the design and fabrication of electrodes for high-performance organic batteries.展开更多
The polymer N2200, with its π-conjugated backbone composed of alternating naphthalene diimide(NDI) and bithiophene(DT)units, has been widely used as an acceptor for all-polymer solar cells(all-PSCs) owing to its high...The polymer N2200, with its π-conjugated backbone composed of alternating naphthalene diimide(NDI) and bithiophene(DT)units, has been widely used as an acceptor for all-polymer solar cells(all-PSCs) owing to its high electron mobility and suitable ionization potential and electron affinity. Here, we developed two naphthalene diimide derivatives by modifying the molecular geometry of N2200 through the incorporation of a truxene unit as the core and NDI-DTas the branches. These starburst polymers exhibited absorption spectra and molecular orbital energy levels that were comparable to N2200. These copolymers were paired with the wide-bandgap polymer donor PTz BI-O to fabricate all-polymer solar cells(all-PSCs), which displayed impressive power conversion efficiencies up to 8.00%. The improved photovoltaic performances of all-PSCs based on these newly developed starburst acceptors can be ascribed to the combination of increased charge carrier mobilities, reduced bimolecular recombination, and formation of more favorable film morphology. These findings demonstrate that the construction of starburst polymer acceptors is a feasible strategy for the fabrication of high-performance all-PSCs.展开更多
文摘Shaped charge jet formation process is studied under the conditions of different background lights by means of high speed frame photography. In order to shoot true jet appearance, the glass tube in which jet moves is vacuumized. The experiment results show that observing jet appearance with the double reflecting mirrors system is feasible as long as the vacuum of the glass tube can meet the requirement of experiment.
基金supported by the National Natural Science Foundation of China (51672188 and 52073211)。
文摘To address the dissolution issue and enhance the electrochemical performance of organic electrode materials,herein, a bipolar organic cathode was prepared by in-situ electropolymerization of amino-phenyl carbazole naphthalene diimide(APCNDI). APCNDI is composed of n-type 1,4,5,8-naphthalene tetracarboxylic diimide that stores Li cations and p-type carbazole groups which react with anions and serve as polymerization sites. Electropolymerization completely eliminated the dissolution problem of APCNDI, and the electropolymerized cathode demonstrated a bipolar reaction with excellent electrochemical performance, stable cycling performance with a capacity retention of 92 mA h g;after1000 cycles, and a superior rate performance of 72 mA h g;at 10 A g;. The bipolar feature and reactions of APCNDI were systematically investigated and verified by multiple characterization techniques. Our findings provide a novel strategy for the design and fabrication of electrodes for high-performance organic batteries.
基金supported by the Ministry of Science and Technology of China(2014CB643501)the National Natural Science Foundation of China(51673069,91633301,21520102006,21761132001)+1 种基金Foundation of Guangzhou Science and Technology Project(201707020019,201607020010)the Pearl River S&T Nova Program of Guangzhou(201710010021)
文摘The polymer N2200, with its π-conjugated backbone composed of alternating naphthalene diimide(NDI) and bithiophene(DT)units, has been widely used as an acceptor for all-polymer solar cells(all-PSCs) owing to its high electron mobility and suitable ionization potential and electron affinity. Here, we developed two naphthalene diimide derivatives by modifying the molecular geometry of N2200 through the incorporation of a truxene unit as the core and NDI-DTas the branches. These starburst polymers exhibited absorption spectra and molecular orbital energy levels that were comparable to N2200. These copolymers were paired with the wide-bandgap polymer donor PTz BI-O to fabricate all-polymer solar cells(all-PSCs), which displayed impressive power conversion efficiencies up to 8.00%. The improved photovoltaic performances of all-PSCs based on these newly developed starburst acceptors can be ascribed to the combination of increased charge carrier mobilities, reduced bimolecular recombination, and formation of more favorable film morphology. These findings demonstrate that the construction of starburst polymer acceptors is a feasible strategy for the fabrication of high-performance all-PSCs.