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991.
在本工作中,我们分别采用薄靶和厚靶实验技术,测量了12C+13C反应在质心系能量4~6 MeV的熔合截面。实验得到了12C+13C反应的在线γ产额和离线的24Na活度,利用TALYS统计模型给出的反应道分支比,导出了熔合反应的总截面。通过对比不同实验得到的总截面,定量研究了统计模型修正所带来的系统误差:在线γ分支比修正引入的系统误差为14%;由离线24Na活度测量得到总截面时,24Na分支比修正带来的系统误差也为14%。 相似文献
992.
993.
Peiyao XUE Junxiang ZHANG Jingming XIN Jeromy RECH Tengfei LI Kaixin MENG Jiayu WANG Wei MA Wei YOU Seth R. MARDER Ray P. S. HAN Xiaowei ZHAN 《物理化学学报》2019,35(3):275-283
Ternary blends have been considered as an effective approach to improve power conversion efficiency (PCE) of organic solar cells (OSCs). Among them, the fullerene-containing ternary OSCs have been studied extensively, and their PCEs are as high as over 14%. However, all non-fullerene acceptor ternary OSCs are still limited by their relatively lower PCEs. In this work, we used wide-bandgap benzodithiophene-difluorobenzotriazole copolymer FTAZ as the donor, low-bandgap fused-ring electron acceptor (FREA), fused tris(thieno- thiophene) end-capped by fluorinated 1, 1-dicyanomethylene-3-indanone (FOIC) as acceptor, and two medium-bandgap FREAs, indaceno-dithiophene end- capped by 1, 1-dicyanomethylene-3-indanone (IDT-IC) and indacenodithiophene end-capped by 1, 1-dicyanomethylene-3-benzoindanone (IDT-NC), as the third components to fabricate the ternary blends FTAZ:FOIC:IDT-IC and FTAZ:FOIC:IDT-NC, and investigated the effects of the third components on the performance of ternary OSCs. Both IDT-IC and IDT-NC are based on the same indacenodithiophene core but contain different terminal groups (phenyl and naphthyl). Relative to IDT-IC with phenyl terminal groups, IDT-NC with naphthyl terminal groups has extended π-conjugation, down-shifted lowest unoccupied molecular orbital (LUMO), red-shifted absorption and higher electron mobility. The binary devices based on the FTAZ:FOIC, FTAZ:IDT-IC and FTAZ:IDT-NC blends exhibit PCEs of 9.73%, 7.48% and 7.68%, respectively. Compared with corresponding binary devices, both ternary devices based on FTAZ:FOIC:IDT-IC and FTAZ:FOIC:IDT-NC exhibit better photovoltaic performances. When the IDT-IC weight ratio in acceptors is 50%, the FTAZ:FOIC:IDT-IC ternary devices exhibit the best PCE of 11.2%. The ternary-blend OSCs yield simultaneously improved open-circuit voltage (VOC), short-circuit current density (JSC) and fill factor (FF) compared with the binary devices based on FTAZ:FOIC. The higher VOC is attributed to the higher LUMO energy level of IDT-IC compared with FOIC. The improved JSC is attributed to the complementary absorption of FOIC and IDT-IC. The introduction of IDT-IC improves blend morphology and charge transport, leading to higher FF. The FTAZ:FOIC:IDT-NC system yields a higher PCE of 10.4% relative to the binary devices based on FTAZ:FOIC as the active layer. However, the PCE of the FTAZ:FOIC:IDT-NC-based ternary devices is lower than that of the FTAZ:FOIC:IDT-IC-based ternary devices. Compared with the binary devices based on FTAZ:FOIC, in FTAZ:FOIC:IDT-NC-based ternary devices, as the ratio of the third component increases, the VOC increases due to the higher LUMO energy level of IDT-NC, the FF increases due to optimized morphology and improved charge transport, while the JSC decreases due to the overlapped absorption of FOIC and IDT-NC. The terminal groups in the third components affect the performance of the ternary OSCs. The lower LUMO. energy level of IDT-NC is responsible for the lower VOC of the FTAZ:FOIC:IDT-NC devices. The red-shifted absorption of IDT-NC leads to the overlapping of the absorption spectra of IDT-NC and FOIC and lower JSC. On the other hand, replacing the phenyl terminal groups by the naphthyl terminal groups influences the π-π packing and charge transport. The FTAZ:FOIC:IDT-NC blend exhibits higher electron mobility and more balanced charge transport than FTAZ:FOIC:IDT-IC, leading to a higher FF. 相似文献
994.
建立了能够同时测定蛋白胨中9种B族维生素的超高效液相色谱-串联质谱法(UPLC-MS/MS)。样品经水溶解后,滤液经Syncronis C18色谱柱分离,采用电喷雾电离源,正离子、多反应监测模式进行检测,分析时间8 min,外标法定量。结果表明,9种B族维生素在各自质量浓度范围内线性良好,相关系数(R2)均大于0.999,方法的检出限为0.09~1.67 μg/L,方法的相对标准偏差均<3%(n=6);9种B族维生素不同添加水平下的平均回收率为80.2%~103.9%。该方法简便、准确,灵敏度高,适用于蛋白胨中B族维生素的测定。 相似文献
995.
在甲醇和二氯甲烷的混合溶剂中合成了2个新的铜(1)配合物,[Cu(bdppmapy)(2,2′-bipy)]BF4(1)和[Cu(bdppmapy)(2,2′-bipy)]I (2)(bdppmapy=N,N-二苯基膦甲基-2-氨基吡啶,2,2′-bipy=2,2′-联吡啶),通过X射线单晶衍射、元素分析、核磁共振氢谱、磷谱、荧光光谱和太赫兹时域光谱对2个配合物进行了分析和表征。1是由[Cu(CH3CN)4]BF4,bdppmapy和2,2′-bipy以1∶1∶1的比例混合得到的单核配合物。中心Cu(1)离子通过与双膦配体(bdppmapy)以及含氮配体(2,2′-bipy)的螯合作用形成变形四面体结构。与1相似,2由CuI,bdppmapy和2,2′-bipy以1∶1∶1的比例混合得到。在配合物2的非对称单元中,bdppmapy和2,2′-bipy配体分别与中心铜(1)离子螯合。荧光光谱表明所有的发射峰均源于金属-配体的荷移跃迁(MLCT)。太赫兹时域光谱的应用也为配合物研究提供了有用的信息。 相似文献
996.
合成了2个新的铜(Ⅰ)配合物,[Cu(dppBz)(dpq)]ClO4(1)和[Cu(dppe)(dpq)]ClO4(2)(dppBz=1,2-双(二苯基膦)苯,dppe=1,2-双(二苯基膦)乙烷,dpq=[2,3-f]吡嗪并[1,10]菲咯啉),通过X射线单晶衍射分析、元素分析、红外光谱、紫外吸收光谱、荧光光谱、核磁共振光谱和太赫兹时域光谱对其进行了分析和表征。1的中心Cu(Ⅰ)离子通过二亚胺配体和双膦配体共同螯合形成变形四面体结构,2的结构与1类似。配合物2的发光光谱表明它的发光具有金属-配体电荷转移(MLCT)特性。对配合物1和2在0.2~2.8 THz范围内进行了太赫兹时域光谱分析,结果表明0.40~0.90 THz的吸收与中心Cu(Ⅰ)离子的配位有关。 相似文献
997.
Y. SASAZAWAP. XIN S. SUZUKIT. KAWADA M. KUROIWAY. TAMURA 《Journal of sound and vibration》2002,250(1):91-99
This study was designed to assess the effects of road traffic noise and frogs' croaking on the objective and subjective quality of sleep in a laboratory. The subjects were seven male students aged 19-21 years. They were exposed to recorded road traffic noise and frogs' croaking, with 49·6 and 49·5 dB(A)LAeq , and 71·2 and 56·1 dB(A) LAmax, respectively. The background noise in the experimental room was 31·0 dB(A) LAeq. The sleep EEG was recorded according to standard methods. The sleep polygraphic parameters examined were the percentage of sleep stage relative to the total sleep time (%S1, %S2, %S(3+4), %SREM, %MT), total sleep time, sleep onset latency, and awakening during sleep in minutes and sleep efficiency. A structured sleep rating questionnaire (OSA), was administered to the subjects after they awakened. The %S2 increased and the %SREM decreased during exposure to road traffic noise. However, no significant effect of exposure to frogs' croaking was observed on any of the polygraphic sleep parameters. The subjective quality of sleep was degraded more by exposure to road traffic noise than that to frogs' croaking. 相似文献
998.
999.
1000.