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51.
Donor–Acceptor–Acceptor's Molecules for Vacuum‐Deposited Organic Photovoltaics with Efficiency Exceeding 9%
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Xiaozhou Che Chin‐Lung Chung Chou‐Chun Hsu Feng Liu Ken‐Tsung Wong Stephen R. Forrest 《Liver Transplantation》2018,8(19)
Three vacuum‐deposited donor–acceptor–acceptor (d–a–a') small molecule donors are studied with different side chains attached to an asymmetric heterotetracene donor block for use in high efficiency organic photovoltaics (OPVs). The donor with an isobutyl side chain yields the highest crystal packing density compared to molecules with 2‐ethylhexyl or n‐butyl chains, leading to the largest absorption coefficient and short circuit current in an OPV. It also exhibits a higher fill factor, consistent with its preferred out‐of‐plane molecular π–π stacking arrangement that facilitates charge transport in the direction perpendicular to the substrate. A power conversion efficiency of 9.3 ± 0.5% is achieved under 1 sun intensity, AM 1.5 G simulated solar illumination, which is significantly higher than 7.5 ± 0.4% of the other two molecules. These results indicate that side chain modification of d–a–a' small molecules offers an effective approach to control the crystal packing configuration, thereby improving the device performance. 相似文献
52.
The current separation of the calcified genera Actinotrichia Decaisne, Galaxaura Lamouroux, and Tricleocarpa Huisman et Borowitzka in the Galaxauraceae is largely based on type of life history (whether the gametophytes and tetrasporophytes are isomorphic or heteromorphic with respect to gross morphology or cortical‐cell features) and on features of postfertilization development (such as the composition of the pericarp). We reexamined the phylogenetic relationships of these genera based on comparative rbcL sequence analysis, types of life cycle, and cystocarp development. Four distinct assemblages have been identified: an Actinotrichia clade, a Tricleocarpa clade, a Galaxaura clade (containing the type species), and a Dichotomaria clade made of a number of formerly Galaxaura species (D. obtusata [Ellis et Solander] Lamarck, D. marginata [Ellis et Solander] Lamarck, and D. diesingiana [Zanardini] Huisman, Harper and Saunders). Key differences between Dichotomaria and Galaxaura include the habit of the gametophytic and tetrasporophytic generations (isomorphic in Dichotomaria and dimorphic in Galaxaura) as well as the presence or absence of a persistent pericarp in the cystocarp (present in Dichotomaria and absent in Galaxaura). Molecular data do not support monophyly for the putatively pantropical species Galaxaura rugosa, Dichotomaria obtusata, and D. marginata, all of which we conclude are in need of taxonomic revision. 相似文献
53.
Context-dependent memory: colour versus odour 总被引:2,自引:1,他引:1
An olfactory stimulus and a visual stimulus were employed in a context-
dependent memory study using a prose passage as the to-be-remembered item.
Ninety-five university students (aged 17-35 years) learned the passage of
prose in the presence of one of the stimuli and were then asked to recall
the passage with the original context either reinstated or not reinstated.
The results revealed a significant context-dependent memory effect for the
olfactory cue but not for the visual cue. They demonstrate support for the
effectiveness of odours as context cues and it is suggested that
context-dependent memory processes may underlie the formation and retrieval
of odour-evoked autobiographical memories.
相似文献
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