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In the development of high‐performance organic solar cells (OSCs), the self‐organization of organic semiconductors plays a crucial role. This study focuses on the precisely manipulation of molecular assemble via tuning alkyl side‐chain topology in a series of low‐cost nonfused‐ring electron acceptors (NFREAs). Among the three NFREAs investigated, DPA‐4, which possesses an asymmetric alkyl side‐chain length, exhibits a tight packing in the crystal and high crystallinity in the film, contributing to improved electron mobility and favorable film morphology for DPA‐4. As a result, the OSC device based on DPA‐4 achieves an excellent power conversion efficiency of 16.67 %, ranking among the highest efficiencies for NFREA‐based OSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing thiazole and 4‐chlorothiazole as the A′ units, two A‐D‐A′‐D‐A type nonfused‐ring electron acceptors (NFREAs) Tz‐H and Tz‐Cl were designed and synthesized. Replacing thiazole in Tz‐H with 4‐chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S···N and S···Cl noncovalently conformational locks (NoCLs). The photovoltaic devices based on PM6:Tz‐Cl exhibited a power conversion efficiency as high as 11.10%, much higher than that of PM6:Tz‐H (6.41%), mainly due to more efficient exciton dissociation, better and more balanced carrier mobility, less charge recombination, and more favorable morphology. These findings demonstrate the great potential of NoCLs in achieving low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: By employing thiazole and 4‐chlorothiazole as the A′ units, two A‐D‐A′‐D‐A type nonfused‐ring electron acceptors (NFREAs) Tz‐H and Tz‐Cl were designed and synthesized. Replacing thiazole in Tz‐H with 4‐chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S···N and S···Cl noncovalently conformational locks (NoCLs). The photovoltaic devices based on PM6:Tz‐Cl exhibited a power conversion efficiency as high as 11.10%, much higher than that of PM6:Tz‐H (6.41%), mainly due to more efficient exciton dissociation, better and more balanced carrier mobility, less charge recombination, and more favorable morphology. These findings demonstrate the great potential of NoCLs in achieving low‐cost and high‐performance NFREAs. [ABSTRACT FROM AUTHOR]

Many breakthroughs on security and privacy-preserving techniques have emerged to mitigate the trust loss of cloud hosting environment caused by various types of attacks. To enhance memory-level security of multi-keyword fuzzy search, a widely occurred query request, we take the initiative to apply Trusted Execution Environment (a.k.a TEE) technology to our protocol design which provides hardware-based tamper-proof enclaves. Then we propose the Edit Distance-based Obfuscation Mechanism to further protect the query process executed outside TEE against access pattern leakage. With concerns of practicality and performance, we also propose the two-layer fuzzy index structure and Trend-aware Cache. The former addresses the space limitation of TEE memory for searching large datasets, while the latter optimizes the cache utility of TEE with trend-aware coordinator to effectively reduce the communication overhead. [ABSTRACT FROM AUTHOR]

The diffusion of Sulfate ions in concrete is a complex process and affects the performance of concrete. Experiments on the time-dependent distribution of sulfate ions in concrete under the coupling of pressure load, dry-wet circulation, and sulfate attack, and the diffusion coefficient of sulfate ions with various parameters was tested. The applicability of the cellular automata (CA) theory to simulate the diffusion of sulfate ions was discussed. In this paper, a multiparameter cellular automata (MPCA) model was developed to simulate the impacts of load, immersion ways, and sulfate solution concentration for the diffusion of sulfate ions in concrete. The MPCA model was compared with experimental data, considering compressive stress, sulfate solution concentration, and other parameters. The numerical simulations verify the calculation results based on the MPCA model are in good agreement with the test data. Finally, the applicability of the established MPCA model was also discussed.