Revealing the Microstructure-Related Light-induced Degradation for All-Polymer Solar Cells Based on Regioisomerized End-Capping Groups Acceptors

Given the state-of-the-art impressive power conversion efficiency (PCE) of all-polymer solar cells (all-PSCs) surpassing 17%, it’s getting increasingly urgent to achieve highly stable devices under long-term operational conditions. Herein, the...

Conductive gold nanoparticles assembly linked through interaction between radical cations of ethylene- and propylene-3,4-dioxythiophene mixed tetramer thiolate

A conjugated mixed tetramer consisting of ethylenedioxythiophene (EDOT (E)) and propyrenedioxythiophene (ProDOT (P)) dimers (E2P2) with methylthio end-capping group at the EDOT side was directly introduced via a thiolate linker...

Closed-Cell Rigid Polyimide Foams for High-Temperature Applications: The Effect of Structure on Combined Properties

Closed-cell rigid polyimide foams with excellent thermal stability and combined properties were prepared by thermal foaming of a reactive end-capped polyimide precursor powder in a closed mold. The precursor powder was obtained by thermal treatment of a polyester-amine salt (PEAS) solution derived from the reaction of the diethyl ester of 2,3,3′,4′-biphenyl tetracarboxylic dianhydride (α-BPDE) with an aromatic diamine mixture of p-phenylenediamine (PDA) and 2-(4-aminophenyl)-5-aminobenzimidazole (BIA) in the presence of an end-capping agent (mono-ethyl ester of nadic acid anhydride, NE) in an aliphatic alcohol. The effect of polymer mainchain structures on the foaming processability and combined properties of the closed-cell rigid polyimide foams were systematically investigated. The polyimide foams (100–300 kg/m3) with closed-cell rates of 91–95% show an outstanding thermal stability with an initial thermal decomposition temperature of ≥490 °C and a glass transition temperature of 395 °C. Polyimide foams with density of 250 kg/m3 exhibited compression creep deformation as low as 1.6% after thermal aging at 320 °C/0.4 MPa for 2 h.

Interactions between RNA m6A modification, alternative splicing, and poly(A) tail revealed by MePAIso-seq2

RNA post-transcriptional regulation involves 5-end capping, 3-poly(A) tailing (including polyadenylation sites, tail length, and non-A residues), alternative splicing, and chemical modifications including N6-methyladenosine (m6A). Studying the interplay of m6A, alternative splicing, alternative polyadenylation sites, poly(A) tail length, and non-A residues in poly(A) tails requires monitoring them simultaneously on one transcript, however strategies to achieve this are lacking. Therefore, we developed a new method, combining m6A-specific methylated RNA immunoprecipitation and the PacBio-based, tail-included, full-length RNA sequencing approach PAIso-seq2, which we have named m6A and poly(A) inclusive RNA isoform sequencing 2 (MePAIso-seq2). Using MePAIso-seq2, we revealed that m6A promotes and inhibits a similar number of alternative splicing events in mouse cell lines, showing that m6A does affect alternative splicing. In contrast, no correlation was detected between m6A and alternative polyadenylation sites choice. Surprisingly, we found that m6A-modified RNAs possess longer poly(A) tails and a lower proportion of poly(A) tails containing non-A residues, especially in mouse embryonic stem cells. Together, we developed a new method to detect full-length m6A-modified RNAs to comprehensively study the relationships between m6A, alternative splicing, and poly(A) tailing, laying a foundation for further exploration of the functional coordination of different RNA post-transcriptional modifications.

Completely non-fused electron acceptor with 3D-interpenetrated crystalline structure enables efficient and stable organic solar cell

Non-fullerene acceptors (NFAs) based on non-fused conjugated structures have more potential to realize low-cost organic photovoltaic (OPV) cells. However, their power conversion efficiencies (PCEs) are much lower than those of the fused-ring NFAs. Herein, a new bithiophene-based non-fused core (TT-Pi) featuring good planarity as well as large steric hindrance was designed, based on which a completely non-fused NFA, A4T-16, was developed. The single-crystal result of A4T-16 reveals that a three-dimensional interpenetrating network can be formed due to the compact π–π stacking between the adjacent end-capping groups. A high PCE of 15.2% is achieved based on PBDB-TF:A4T-16, which is the highest value for the cells based on the non-fused NFAs. Notably, the device retains ~84% of its initial PCE after 1300 h under the simulated AM 1.5 G illumination (100 mW cm−2). Overall, this work provides insight into molecule design of the non-fused NFAs from the aspect of molecular geometry control.

Benefits of Innovative and Fully Water-Compatible Stationary Phases of Thin-Film Microextraction (TFME) Blades

Octadecyl (C18) groups are arguably the most popular ligands used for preparation of solid phase microextraction (SPME) devices. However, conventional C18-bonded silica particles are not fully compatible with the nearly 100% aqueous composition of typical biological samples (e.g., plasma, saliva, or urine). This study presents the first evaluation of thin-film SPME devices coated with special water-compatible C18-bonded particles. Device performance was assessed by extracting a mixture of 30 model compounds that exhibited various chemical structures and properties, such as hydrophobicity. Additionally, nine unique compositions of desorption solvents were tested. Thin-film SPME devices coated with C18-bonded silica particles with polar end-capping groups (10 µm) were compared with conventional trimethylsilane end-capped C18-bonded silica particles of various sizes (5, 10, and 45 µm) and characteristics. Polar end-capped particles provided the best extraction efficacy and were characterized by the strongest correlations between the efficacy of the extraction process and the hydrophobicity of the analytes. The results suggest that the original features of octadecyl ligands are best preserved in aqueous conditions by polar end-capped particles, unlike with conventional trimethylsilane end-capped particles that are currently used to prepare SPME devices. The benefits associated with this improved type of coating encourage further implementation of microextractraction as greener alternative to the traditional sample preparation methods.