Based on the boron-containing thermally activated delayed fuorescence(TADF)compound p-AC(AC:acridine)5,9-dioxa-13 b-boranaphtho[3,2,1-de]anthracene(a),a series of new TADF molecules b1-b4 were designed via adding two ...Based on the boron-containing thermally activated delayed fuorescence(TADF)compound p-AC(AC:acridine)5,9-dioxa-13 b-boranaphtho[3,2,1-de]anthracene(a),a series of new TADF molecules b1-b4 were designed via adding two nitrogen atoms at the AC donor part.Density functional theory and time-dependent density functional theory calculations were performed on the frontier orbital energy levels,emission spectra,singlet-triplet states energy gaps(?EST),reverse intersystem crossing(RISC)rate constant(kRISC)for compounds a and b1-b4.Our calculation results show that the maximum emission wavelengths of b1-b4 are significantly blue-shifted by47-125 nm compared with that of a.Molecules b1 and b3 exhibit dark-blue emission,while molecules b2 and b4 display light-blue emission,indicating that these four derivatives could be potential organic light-emitting diode(OLED)candidates with blue-light emitting.Moreover,we found the RISC processes in a,b2,and b4 can occur not only from T_(1) state to S_(1) state,but also from T_(2) state to S_(1) state significantly,while the RISC processes in b1 and b3 mainly take place via the T_(2)→S_(1) hot exciton way.Importantly,the T_(1)→S_(1) kRISC values of b2 and b4 are predicted to be two to three times of that of a,indicating enhanced TADF property.Our results not only provide two promising boron-based TADF candidates(b2 and b4),but also offer useful theoretical basis for the design of blue OLED materials.展开更多
The effects of different dietary lipid content on the growth and lipase activity ofEriocheir sinensis larvae were studied in the paper. The results showed that the survival, metamorphic rate and weight gain of E. sine...The effects of different dietary lipid content on the growth and lipase activity ofEriocheir sinensis larvae were studied in the paper. The results showed that the survival, metamorphic rate and weight gain of E. sinensis larvae at different stages of growth all varied significantly with lipid content (P〈0.05). Further, the survival and metamorphosis rates were the highest during the larval phases Z3 to Z4, and the weight gain was the highest during the larval phases Z5 to M. During the first 20h after metamorphosis of every larval stage, the lipase activity increased over time at Z1, Z2, Z3 and M and declined at Z4 and Zs, and was influenced significantly by lipid content (P〈0.05). In addition, lipase activity at each larval stage began to respond to dietary lipid contents 4h after the larvae were fed, and tended to be stable after 12 h. The diets with higher lipase activity and lower lipid content were selected to give the suitable recipe of lipid requirements at each larval stage. It was concluded that the suitable lipid requirements at Zb Z2, Z3, Z4, Z5 and M were 6%, 4% 6%, 8%, 8% and 10%, respectively.展开更多
基金supported by the National Natural Science Foundation of China(No.22173008)。
文摘Based on the boron-containing thermally activated delayed fuorescence(TADF)compound p-AC(AC:acridine)5,9-dioxa-13 b-boranaphtho[3,2,1-de]anthracene(a),a series of new TADF molecules b1-b4 were designed via adding two nitrogen atoms at the AC donor part.Density functional theory and time-dependent density functional theory calculations were performed on the frontier orbital energy levels,emission spectra,singlet-triplet states energy gaps(?EST),reverse intersystem crossing(RISC)rate constant(kRISC)for compounds a and b1-b4.Our calculation results show that the maximum emission wavelengths of b1-b4 are significantly blue-shifted by47-125 nm compared with that of a.Molecules b1 and b3 exhibit dark-blue emission,while molecules b2 and b4 display light-blue emission,indicating that these four derivatives could be potential organic light-emitting diode(OLED)candidates with blue-light emitting.Moreover,we found the RISC processes in a,b2,and b4 can occur not only from T_(1) state to S_(1) state,but also from T_(2) state to S_(1) state significantly,while the RISC processes in b1 and b3 mainly take place via the T_(2)→S_(1) hot exciton way.Importantly,the T_(1)→S_(1) kRISC values of b2 and b4 are predicted to be two to three times of that of a,indicating enhanced TADF property.Our results not only provide two promising boron-based TADF candidates(b2 and b4),but also offer useful theoretical basis for the design of blue OLED materials.
基金funded by the National Natural Science Foundation of China (No.30100140)the Higher Institutions Doctor research Foundation Projects of China (No.2000042303)the Natural Science Foundation Projects of Province Shandong (No.Y98D15063)
文摘The effects of different dietary lipid content on the growth and lipase activity ofEriocheir sinensis larvae were studied in the paper. The results showed that the survival, metamorphic rate and weight gain of E. sinensis larvae at different stages of growth all varied significantly with lipid content (P〈0.05). Further, the survival and metamorphosis rates were the highest during the larval phases Z3 to Z4, and the weight gain was the highest during the larval phases Z5 to M. During the first 20h after metamorphosis of every larval stage, the lipase activity increased over time at Z1, Z2, Z3 and M and declined at Z4 and Zs, and was influenced significantly by lipid content (P〈0.05). In addition, lipase activity at each larval stage began to respond to dietary lipid contents 4h after the larvae were fed, and tended to be stable after 12 h. The diets with higher lipase activity and lower lipid content were selected to give the suitable recipe of lipid requirements at each larval stage. It was concluded that the suitable lipid requirements at Zb Z2, Z3, Z4, Z5 and M were 6%, 4% 6%, 8%, 8% and 10%, respectively.