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141.
142.
Results of an experimental investigation into the changes of some structural characteristics of binary blends of high-density polyethylene and low-density polyethylene with an elastomer (ethylene-propylene-dicyclopentadiene terpolymer, EPDM) in the course of γ-radiation and chemical cross-linking are reported for a wide range of component ratios. The data on changes in the crystallinity, density of the blends, content of the cross-linked part, as well the correlation of these characteristics with some mechanical properties, are discussed. Suggestions are put forward about the possibility of formation of a combined amorphous PE-EPDM phase with a higher structural arrangement than that in the individual components.__________Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 4, pp. 545–562, July–August, 2005. 相似文献
143.
介绍了大庆油田应用胶态分散凝胶深度调剖技术的凝胶成胶机理、影响成胶的因素、凝胶在多孔介质中的渗流特征及现场试验效果,室内岩芯模拟研究及现场典型井试验表明,流动凝胶在多孔介质中可流动,在单井注入15000-20000m^3流动凝胶体系过程中,注入压力逐渐升高,可以实现深度调剖,更好地提高聚合物驱采收率。 相似文献
144.
145.
Cover Picture: Mechanochromism and Mechanical‐Force‐Triggered Cross‐Linking from a Single Reactive Moiety Incorporated into Polymer Chains (Angew. Chem. Int. Ed. 9/2016)
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146.
Molecularly Designed Stabilized Asymmetric Hollow Fiber Membranes for Aggressive Natural Gas Separation
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Dr. Gongping Liu Dr. Nanwen Li Dr. Stephen J. Miller Danny Kim Dr. Shouliang Yi Dr. Ying Labreche Prof. Dr. William J. Koros 《Angewandte Chemie (International ed. in English)》2016,55(44):13754-13758
New rigid polyimides with bulky CF3 groups were synthesized and engineered into high‐performance hollow fiber membranes. The enhanced rotational barrier provided by properly positioned CF3 side groups prohibited fiber transition layer collapse during cross‐linking, thereby greatly improving CO2/CH4 separation performance compared to conventional materials for aggressive natural gas feeds. 相似文献
147.
Carmen Villegas Aurel Diacon Thérèse Gorisse Lionel Derue Ingrid Freuze Magali Allain Hussein Awada Olivier Dautel Guillaume Wantz Piétrick Hudhomme 《Helvetica chimica acta》2023,106(6):e202300031
This study presents the synthesis and characterization of novel azido molecules with demonstrated crosslinking ability when used as additives in polymer/fullerene organic solar cells. These compounds derived from fullerenes C60 and C70, or dyes from perylenediimide, perylene and tetraphenylethylene frameworks, bearing a different number of azido groups, are of particular interest to stabilize and increase the thermal stability of the device morphology. In particular, the electro and photoactive dye derivatives allow the introduction of additional functionality with the possibility of extending the absorption domain of the photoactive layer. In addition, and more broadly, such azido crosslinkers could find applications in the field of optoelectronic devices as a simple and cheap strategy to improve the performance and long-term stability of organic solar cells, perovskites solar cells, or organic light-emitting diodes. 相似文献
148.
Weiguo Han Junjie Liu Chunhao Ran Dr. Zhenmei Huang Prof. Dr. Ge Gao Prof. Dr. Jingsong You Prof. Dr. Zhengyang Bin 《Angewandte Chemie (International ed. in English)》2023,62(48):e202312297
The endeavor to develop high-performance narrowband blue organic light-emitting diodes (OLEDs) with low efficiency roll-off represents an attractive challenge. Herein, we introduce a hetero-acceptor design strategy centered around the heptagonal diimide (BPI) building block to create an efficient thermally activated delayed fluorescence (TADF) sensitizer. The alignment of a twisted BPI unit and a planar diphenyltriazine (TRZ) fragment imparts remarkable exciton dynamic properties to 26tCz-TRZBPI, including a fast radiative decay rate (kR) of 1.0×107 s−1 and a swift reverse intersystem crossing rate (kRISC) of 1.8×106 s−1, complemented by a slow non-radiative decay rate (kNR) of 6.0×103 s−1. Consequently, 26tCz-TRZBPI facilitates the fabrication of high-performance narrowband pure-blue TADF-sensitized fluorescence OLEDs (TSF-OLEDs) with a maximum external quantum efficiency (EQEmax) of 24.3 % and low efficiency roll-off even at a high brightness level of 10000 cd m−2 (EQE10000: 16.8 %). This showcases a record-breaking external quantum efficiency at a high luminance level of 10000 cd m−2 for narrowband blue TSF-OLEDs. 相似文献
149.
Tobias Hedtke Mathias Mende Heiko Steenbock Jürgen Brinckmann Matthias Menzel Wolfgang Hoehenwarter Markus Pietzsch Thomas Groth Christian E. H. Schmelzer 《Macromolecular bioscience》2023,23(11):2300203
Elastin is an essential extracellular matrix protein that enables tissues and organs such as arteries, lungs, and skin, which undergo continuous deformation, to stretch and recoil. Here, an approach to fabricating artificial elastin with close-to-native molecular and mechanical characteristics is described. Recombinantly produced tropoelastin are polymerized through coacervation and allysine-mediated cross-linking induced by pyrroloquinoline quinone (PQQ). A technique that allows the recovery and repeated use of PQQ for protein cross-linking by covalent attachment to magnetic Sepharose beads is developed. The produced material closely resembles natural elastin in its molecular, biochemical, and mechanical properties, enabled by the occurrence of the cross-linking amino acids desmosine, isodesmosine, and merodesmosine. It possesses elevated resistance against tryptic proteolysis, and its Young's modulus ranging between 1 and 2 MPa is similar to that of natural elastin. The approach described herein enables the engineering of mechanically resilient, elastin-like materials for biomedical applications. 相似文献
150.
Dongyang Chen Francisco Tenopala-Carmona Julius A. Knöller Andreas Mischok David Hall Subeesh Madayanad Suresh Tomas Matulaitis Yoann Olivier Pierre Nacke Frank Gießelmann Sabine Laschat Malte C. Gather Eli Zysman-Colman 《Angewandte Chemie (International ed. in English)》2023,62(16):e202218911
The use of thermally activated delayed fluorescence (TADF) emitters and emitters that show preferential horizontal orientation of their transition dipole moment (TDM) are two emerging strategies to enhance the efficiency of OLEDs. We present the first example of a liquid crystalline multi-resonance TADF (MR-TADF) emitter, DiKTa-LC . The compound possesses a nematic liquid crystalline phase between 80 °C and 110 °C. Importantly, the TDM of the spin-coated film shows preferential horizontal orientation, with an anisotropy factor, a, of 0.28, which is preserved in doped poly(vinylcarbazole) films. Green-emitting (λEL=492 nm) solution-processed OLEDs based on DiKTa-LC showed an EQEmax of 13.6 %. We thus demonstrate for the first time how self-assembly of a liquid crystalline TADF emitter can lead to the so-far elusive control of the orientation of the transition dipole in solution-processed films, which will be of relevance for high-performance solution-processed OLEDs. 相似文献