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排序方式: 共有114条查询结果,搜索用时 490 毫秒
21.
Jieni Li Henan Li Lai Liu Huizhen Yao Bingbing Tian Chenliang Su Haizhe Zhong Ye Wang Lifu Zhang Yumeng Shi 《化学:亚洲杂志》2019,14(16):2861-2868
Organometallic halide perovskites have attracted great research interest as light‐active materials for use in optoelectronics. Here, we report a high‐performance photoconductor based on a methylammonium lead iodide (MAPbI3) film that was prepared from a methylamine‐treated MAPbI3/PbI2 perovskite film. An ultrahigh responsivity of 3.6 A W?1 and detectivity of 5.4×1012 Jones were obtained for the film under 0.5 mW cm?2 white‐light illumination. In addition, under 420 nm light irradiation, the film exhibited its highest responsivity and detectivity of 30 A W?1 and 2.4×1014 Jones, respectively. The excellent photo‐response performance results from the improved electronic quality and suppressed nonradiative recombination channels of the treated perovskite thin film. 相似文献
22.
采用单茂钛化合物CpTiCl3,有机环氧化合物1,4-丁二醇二缩水甘油基醚(BDGE),金属锌(Zn)及甲基铝氧烷(MAO)为催化体系,通过自由基聚合和配位聚合机理合成无规聚苯乙烯-b-聚(苯乙烯-co-乙烯)-b-聚乙烯(aPS-b-P(S-co-E)-b-PE).探讨了温度、时间、乙烯压力及Al/Ti摩尔比对共聚合的影响.所得嵌段共聚物采用DSC,WAXD,GPC和13C-NMR等手段进行了表征.结果表明该共聚物是苯乙烯/乙烯嵌段共聚物,聚苯乙烯链段是无规的,聚乙烯链段具有结晶性. 相似文献
23.
Feng Xu Lei Zhang Liyun Jiang Lifu Bao Hao Meng 《International journal of quantum chemistry》2016,116(1):7-12
Quantum tunneling effect in entanglement dynamics between two coupled particles with separable Gaussian initial state is investigated using entangled trajectory molecular dynamics method in terms of the reduced‐density linear entropy. It has been presented through showing distinguish contribution of single trajectory to linear entropy between classical trajectory and entangled trajectory with same initial state. We find that quantum tunneling effect makes single trajectory's contribution remarkably decrease under quantum dynamics compared to classical dynamics. The nonlocality of quantum entanglement is presented, and the energy transfer between two coupled particles through quantum correlations and classical ones is also discussed in the end. © 2015 Wiley Periodicals, Inc. 相似文献
24.
Nan Du Lifu Liao Yongjun Xiao Xilin Xiao Zhiyuan Zhao Yingwu Lin Changming Nie 《Radiation measurements》2012,47(5):371-374
A wireless sensing method for the measurement of gamma radiation dose has been developed based on the fact that gamma rays can initiate the polymerization of acrylamide, which causes an increase in solution viscosity that can be detected with a wireless magnetoelastic sensor. The magnetoelastic sensor is able to wirelessly detect the resonance frequency shifts of a magnetoelastic foil in response to changes in solution viscosity. There is a linear relationship between the resonance frequency shift and gamma radiation dose in the range of 0–50 Gy (under optimal conditions) with a detection limit of 0.25 Gy. This method has the advantage of providing real-time, continuous measurement in situ. The method has been used successfully to determine the gamma radiation dose in real exposure scenarios, with satisfactory results. 相似文献
25.
一般加载规律的弹塑性本构关系 总被引:1,自引:1,他引:0
将有关文献给出一般加载规律一维全量理论的简单模型推广到一般加载规律的一维增量理论,进而推广到一般加载规律的多维增量理论,在此基础上,建立了推导一般加载规律的多维增量理论的本构关系的一种途径。应用这种途径,从应力空间的加载函数和应变空间的加载函数出发,推导了等向强化材料和被加热的等向强化材料的一般加载规律的弹塑性本构关系的两种表示形式。理论和实例均表明,这种途径对等向强化材料、随动强化材料和理想弹塑性材料均适用。 相似文献
26.
Yuanyuan Yang Lifu Zhang Prof. Zhenpeng Hu Dr. Yao Zheng Dr. Cheng Tang Prof. Ping Chen Ruguang Wang Kangwen Qiu Dr. Jing Mao Prof. Tao Ling Prof. Shi-Zhang Qiao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(11):4555-4561
Cost-effective carbon-based catalysts are promising for catalyzing the electrochemical N2 reduction reaction (NRR). However, the activity origin of carbon-based catalysts towards NRR remains unclear, and regularities and rules for the rational design of carbon-based NRR electrocatalysts are still lacking. Based on a combination of theoretical calculations and experimental observations, chalcogen/oxygen group element (O, S, Se, Te) doped carbon materials were systematically evaluated as potential NRR catalysts. Heteroatom-doping-induced charge accumulation facilitates N2 adsorption on carbon atoms and spin polarization boosts the potential-determining step of the first protonation to form *NNH. Te-doped and Se-doped C catalysts exhibited high intrinsic NRR activity that is superior to most metal-based catalysts. Establishing the correlation between the electronic structure and NRR performance for carbon-based materials paves the pathway for their NRR application. 相似文献
27.
本文首先定性描述了汽车驾驶员必须具备的身体素质,然后用多元统计分析方法对测试结果进行统计分析.文中提出的方法可供制定汽车驾驶员职业适应性标准参考. 相似文献
28.
非完整系统Hamilton原理的驻值特性 总被引:3,自引:0,他引:3
本文论证了非完整系统的Hamilton原理的驻值特性,指出运用Appell-Chetaev条件的Hamilton原理和不应用appell-Chetaev条件的Hamilton原理都是驻值变分原理.并且,讨论了几个有关问题. 相似文献
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