A Dual Analysis of Verb-less Coordination in Korean

This paper explores the nature of verb-less coordination (VLC) in Korean. Various proposals have been made to explain the peculiar properties of VLC: movement analysis, string deletion analysis, and multiple dominance analysis. We show that none of these analyses are fully satisfactory by observing apparent mismatches between elided parts in the first conjunct and the shared parts in the second conjuncts. We claim that ellipsis analysis is basically correct in capturing apparent mismatches which we coin as vehicle change effects. However, we further propose that some VLC constructions are instances of multiple fragments. Hence VLC in Korean exhibits the dual nature. We show that multiple fragments analysis of VLC is selectively available only with distributed reading of the shared verb, otherwise ellipsis analysis of it is forced by default

Interactions between subjective memory complaint and objective cognitive deficit on memory performances

Background Subjective memory complaint (SMCs) is a common trait amongst older population. The subjective cognition about their memory could depend on objective cognition. The aim of the current study was to examine the interaction between subjective memory cognition (i.e., SMC) and objective cognition on cognitive functions in participants from older generation. Methods A total of 219 patients, 181 normal control (NC) patients and 38 patients with mild cognitive impairment (MCI), were examined through standardized and comprehensive clinical evaluation and neuropsychological assessment. The Subjective Memory Complaints Questionnaire was used to assess SMCs along with five cognitive tasks were used to evaluate cognitive decline over following areas: verbal memory, visuospatial memory, attention, fluency, and language. Results The results of 2 × 2 two-way analysis of variance (ANOVA) showed that there were significant interactions between SMCs and cognitive status (NC, MCI) on memory performances. NC with SMCs showed significantly lower performance in verbal memory and visuospatial memory compared to NCs without SMCs. Conversely, no effect was observed in the MCI group. Conclusion There are interactions between subjective cognition (i.e., SMC) and objective cognition (i.e., cognitive status) on memory performances in older adults. The roles of SMCs on memory performances should be interpreted with older adults objective cognitive status.This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. NRF-2017R1D1A1A02018479). This funding source had no role in the design of this study and will not have any role during its execution, analyses, interpretation of the data, or decision to submit result

Silicon and oxygen synergistic effects for the discovery of new high-performance nonfullerene acceptors

In organic electronics, an aromatic fused ring is a basic unit that provides -electrons to construct semiconductors and governs the device performance. The main challenge in developing new pi -skeletons for tuning the material properties is the limitation of the available chemical approach. Herein, we successfully synthesize two pentacyclic siloxy-bridged pi -conjugated isomers to investigate the synergistic effects of Si and O atoms on the geometric and electronic influence of pi -units in organic electronics. Notably, the synthesis routes for both isomers possess several advantages over the previous approaches for delivering conventional aromatic fused-rings, such as environmentally benign tin-free synthesis and few synthetic steps. To explore their potential application as photovoltaic materials, two isomeric acceptor-donor-acceptor type acceptors based on these two isomers were developed, showing a decent device efficiency of 10%, which indicates the great potential of this SiO-bridged ladder-type unit for the development of new high-performance semiconductor materials.Developing a new pi -skeletal aromatic fused-ring for tuning material properties in organic electronics is still a challenge due to limited chemical approach. Here, the authors enrich the chemistry by synthesizing SiO-bridged ladder-type pi -skeletons with enhanced planarity and deeper energy levels than CO-bridged counterpart

Structure Engineering of N-type Organic Conjugated Materials toward Next-generation Optoelectronics

School of Energy and Chemical Engineering (Energy Engineering)clos

Tuning Polarity in Naphthalenediimide-Based Field-Effect Transistors through Incorporation of Alkoxy-Bithiophene Unit

The recent development of low-band-gap polymers comprising alternating donor and acceptor units in the backbone led to an improvement in the charge transport properties of organic field-effect transistors (OFETs). Among many conjugated semiconducting materials, P(NDI2OD-T2) (also known as Polyera ActivInk N2200) is well-known as a top-performing n-channel material comprising a naphthalenediimide acceptor and a bithiophene donor units. Herein, we report ambipolar OFETs based on (NDI2OD-T2) analogous polymers by introducing simultaneously the alkoxy-bithiophene unit and changing of alkyl branching point. This study advances our fundamental understanding of how polymer structure influences dominant polarity of charge carriers and reveals a new synthetic strategy for the design of ambipolar semiconducting materials

Effect of Third Component on Efficiency and Stability in Ternary Organic Solar Cells: More than a Simple Superposition

Ternary organic solar cells (OSCs) have attracted much attention due to them being high-performance solar cells. Ternary OSCs represent an efficient strategy to gain both the benefits of enhanced photon energy harvesting using multiple organic materials, similar to that in tandem OSCs, and the easy fabrication of simple single-junction device structures. The properties of ternary OSCs are closely related to their complex energy/charge dynamics mechanisms and unique thermodynamic features of blend morphology and crystallinity. Hence, there is much more to introducing a third component into a binary blend than the simple superposition of individual components. Herein, the role of the third component is mainly discussed to provide in-depth insights into ternary OSCs. This review categorizes and describes the effects that the role and function of the third component have on the efficiency and stability of ternary OSCs. Finally, in addition to a summary on the current research progress, outlooks for future research directions are also addressed

Naphthalene diimide-based random terpolymers with axisymmetric and asymmetric electron acceptors for controllable morphology and enhanced fill factors in all-polymer solar cells

All-polymer solar cells (all-PSCs), based on p-type polymer donors and n-type acceptors as the active layer, offer exceptional promise because of excellent thermal stability, superior film formation, and good mechanical stress as a unique bulk heterojunction (BHJ) solar cell combination. Therefore, tuning the molecular composition between polymers is crucial for optimizing power conversion efficiency (PCE) in these all-PSC systems. In this study, we synthesized a series of naphthalene diimide (NDI)-based random terpolymers P(NDI-BDD10), P(NDI-TPD10), P(NDI-TT10), and P(NDI-2FQ10) with axisymmetric (BDD, TPD) and asymmetric (TT, 2FQ) electron acceptors. Compared with the blend morphology of PBDB-T:N2200, their diverse effects due to the addition of trace amounts of axisymmetric and asymmetric components were comprehensively investigated using physical and surface analyses and structural simulations. Consequently, most of our polymer acceptors demonstrated improved fill factors (FFs) in the optimal morphology. P(NDI-BDD10)-based devices achieved the highest PCE of 6.80% and FF of 69.1%, while the architecturally most asymmetric P(NDI-TT10)-based devices reached the lowest PCE of 4.52% despite an enhanced FF of 65.4%. As a result, the appropriate molecular arrangement is crucial for obtaining the desired morphology and improved PCE. Our findings give novel molecular design insight into the distinctions between axisymmetric and asymmetric electron acceptors and seem significant for achieving improved morphological features and efficiency

Toxic Solvent??? and Additive???Free Efficient All???Polymer Solar Cells via a Simple Random Sequence Strategy in Both Donor and Acceptor Copolymer Backbones

It is extremely important to develop nontoxic solvent and additive???processed high???performance all???polymer solar cells (all???PSCs) that are suitable for printing preparation of large???scale devices. Herein, it is demonstrates that a simple random copolymerization of two acceptor monomers (benzo[1,2???c:4,5???c???]dithiophene???4,8???dione (BDD) and 5,6???difluoro???2H???benzo[d][1,2,3]triazole (FTAZ)), alternating with Si atom???containing benzo[1,2???b:4,5???b???]dithiophene donor comonomer, forms a successful approach by which to synthesize donor copolymers with excellent solubility/processability for nontoxic???solvent???processed all???PSCs. The incorporation of a higher degree of BDD in the backbone lowers the frontier energy levels, as well as redshifts, with higher absorption coefficients; however, it adversely affects solubility in a 2???methyltetrahydrofuran (MeTHF). An impressive power conversion efficiency, of about 8.0%, is achieved from PJ25 (25 mol% BDD)???based all???PSC when paired with N2200???F30 acceptor random copolymer by using MeTHF as the processing solvent without any additive. Another interesting point is that the air stability of the all???PSCs increases with increasing FTAZ content due to strong noncovalent interaction and resistance to humidity and oxidation caused by the F???atoms in FTAZ units. Not only does this study establish a structure???property???performance relationship through a series of structural, morphological, and electrical characterization techniques, but it also provides a promising and easy way to develop nontoxic???solvent???processed high???performance all???PSCs