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Comprehensive Summary: The rapid synthesis of structurally complicated electron donors & acceptors still remains a major challenge in organic solar cells (OSC). In this work, we developed a highly efficient strategy to access long‐chain oligomeric donor and acceptors for OSC applications. A series of cyclopentadithiophene (CPDT) and benzothiadiazole (BT)‐based π‐conjugated oligomers, i.e., three oligomeric acceptors (BTDT)n‐IC (n = 1—3) and one long‐chain oligomeric donor (BTDT)4‐RD, are facilely synthesized by an atom‐ and step‐economical, and labor‐saving direct C—H arylation (DACH) reaction (i.e., C—H/C—Br cross coupling). Note that (BTDT)4‐RD involving five CPDT, four BT and two rhodamine (RD) building blocks is the longest oligomeric donor in the fullerene‐free OSC devices ever reported. The dependence of the structure‐property‐performance correlation of (BTDT)n‐IC (n = 1—3) and (BTDT)4‐RD on the π‐conjugation lengths is thoroughly investigated by opto‐electrochemical measurements, bulk heterojunction (BHJ) OSC devices and microscopies. The (BTDT)1‐IC:PBDB‐T and (BTDT)4‐RD:Y6 BHJs achieve power conversion efficiencies of 9.14% and 4.51%, respectively. Our findings demonstrate that DACH reaction is a powerful tool to tune the opto‐electronic properties and device performances by regulating the lengths of π‐conjugated oligomers with varied numbers of repeating units. [ABSTRACT FROM AUTHOR]

Achieving broadband multitasked integration on an ultrathin interface is pivotal to increasing data capacity. However, broadband bifunctional metasurfaces exhibiting high‐efficiency and crosstalk‐free characteristics are rarely seen. Here, three broadband spin‐decoupled criteria are developed to design the meta‐atoms of high‐efficiency bifunctional metasurfaces. Specifically, six dipole‐loaded quasi‐I‐shaped meta‐atoms are proposed to satisfy the broadband spin‐decoupled criteria in radio band from 8.6 to 17.8 GHz (about 70% bandwidth) with more than 90% efficiency. The metasurface equipped with the proposed meta‐atoms can keep dispersionless phase gradients and crosstalk‐free characteristics in two orthogonal circular polarizations. This work demonstrates the broadband scheme with spin‐decoupled bifunctional metasurface, yielding two independent broadband multimode vortex beams in two completely decoupled helicities. Besides, other possible applications of the proposed meta‐atoms are illustrated from the perspective of the half‐wave plant (polarization control). Accordingly, the other multitasked‐type bifunctional metasurface is fabricated to achieve the broadband integration of two different functionalities: polarization conversion and full‐polarization anomalous refraction. The proposed schemes offer broadband, polarization‐multiplexing, and multitasked‐integration routes for complex electromagnetic wave manipulations within a subwavelength thickness, which can stimulate the development of electromagnetic/optical integration devices with broadband multiplexing techniques. [ABSTRACT FROM AUTHOR]

In the context of media convergence and screen integration, Omni media has become the trend of development in the field of information services, the demand of the high-quality omni media content is more and more intensive. In this paper, an omni media content production and service system is designed that can produce and manage omni media content quickly and efficiently, crop and merge and catalogue media materials conveniently. The platform accomplish those functions of cropping and merging and transcoding source materials by calling Ffmpeg

Comprehensive Summary: The rapid synthesis of structurally complicated electron donors & acceptors still remains a major challenge in organic solar cells (OSC). In this work, we developed a highly efficient strategy to access long‐chain oligomeric donor and acceptors for OSC applications. A series of cyclopentadithiophene (CPDT) and benzothiadiazole (BT)‐based π‐conjugated oligomers, i.e., three oligomeric acceptors (BTDT)n‐IC (n = 1—3) and one long‐chain oligomeric donor (BTDT)4‐RD, are facilely synthesized by an atom‐ and step‐economical, and labor‐saving direct C—H arylation (DACH) reaction (i.e., C—H/C—Br cross coupling). Note that (BTDT)4‐RD involving five CPDT, four BT and two rhodamine (RD) building blocks is the longest oligomeric donor in the fullerene‐free OSC devices ever reported. The dependence of the structure‐property‐performance correlation of (BTDT)n‐IC (n = 1—3) and (BTDT)4‐RD on the π‐conjugation lengths is thoroughly investigated by opto‐electrochemical measurements, bulk heterojunction (BHJ) OSC devices and microscopies. The (BTDT)1‐IC:PBDB‐T and (BTDT)4‐RD:Y6 BHJs achieve power conversion efficiencies of 9.14% and 4.51%, respectively. Our findings demonstrate that DACH reaction is a powerful tool to tune the opto‐electronic properties and device performances by regulating the lengths of π‐conjugated oligomers with varied numbers of repeating units. [ABSTRACT FROM AUTHOR]