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111.
Tetramerization of coil-rod-coil ABC triblock copolymers to a tetrabranched molecule induces an unusual 3-D tetragonally perforated layered liquid crystalline phase as an intermediate structure between 1-D lamellar and 2-D hexagonal columnar phases. 相似文献
112.
A series of polyester-based ionomers containing dimethyl 5-sulfoisophthalate sodium salt (DMSI) with up to 5 mol-% diacid units was synthesized by two-step polycondensation. Furthermore a polylactic acid (PLA) was modified by introducing poly(ethylene-co-methacrylic acid) ionomers with different ion groups, such as Na, Li, and Zn, using the melt blending method. This review examines the effect of the ionic group on the dynamic mechanical properties, melt rheology, crystallization behavior, degradation behavior, and biocompatibility with human dermal cells, as well as the nucleating effect of poly(ethylene-co-methacrylic acid) ionomer in PLA. 相似文献
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114.
Hye-Young Lee You-Jin Choi Eun-Jung Jung Hu-Quan Yin Jung-Taek Kwon Ji-Eun Kim Hwang-Tae Im Myung-Haing Cho Ju-Han Kim Hyun-Young Kim Byung-Hoon Lee 《Journal of nanoparticle research》2010,12(5):1567-1578
Silver nanoparticles (AgNP) are among the fastest growing product categories in the nanotechnology industry. Despite the importance of AgNP in consumer products and clinical applications, relatively little is known regarding AgNP toxicity and its associated risks. We investigated the effects of AgNP on gene expression in the mouse brain using Affymetrix Mouse Genome Arrays. C57BL/6 mice were exposed to AgNP (geometric mean diameter, 22.18 ± 1.72 nm; 1.91 × 107 particles/cm3) for 6 h/day, 5 days/week using the nose-only exposure system for 2 weeks. Total RNA isolated from the cerebrum and cerebellum was subjected to hybridization. From over 39,000 probe sets, 468 genes in the cerebrum and 952 genes in the cerebellum were identified as AgNP-responsive (one-way analysis of variance; p < 0.05). The largest groups of gene products affected by AgNP exposure included 73 genes in the cerebrum and 144 genes in the cerebellum. AgNP exposure modulated the expression of several genes associated with motor neuron disorders, neurodegenerative disease, and immune cell function, indicating potential neurotoxicity and immunotoxicity associated with AgNP exposure. Real-time PCR data for five genes analyzed from whole blood showed good correlation with the observed changes in the brain. Following rigorous validation and substantiation, these genes may assist in the development of surrogate markers for AgNP exposure and/or toxicity. 相似文献
115.
Binary vapor liquid equilibrium data were measured for the 1,1,1-trifluoroethane (HFC-143a) + dimethyl ether (DME) system at temperatures from 313.15 K to 363.15 K. These experiments were carried out with a circulating-type apparatus with on-line gas chromatograph analysis. The experimental data were correlated well by the Peng-Robinson equation of state using the Wong-Sandler mixing rules. 相似文献
116.
To address if the non‐triphenylamine derivative hole transporting materials such as P3HT (poly‐3‐hexylthiophene) could also exhibit high device efficiency in mesoscopic MAPbI3 perovskite solar cells, we examined the effect of Li‐TFSI (Li‐bis(trifluoromethanesulfonyl) imide) and t‐BP (4‐tert‐butylpyridine) additives added in P3HT on device performance. Unlike the triphenylamine HTMs, the P3HT thiophene HTM without amine moiety was not doped by the additives but its conductivity was significantly improved by the Li‐TFSI/t‐BP mediated additional hole conduction. By inclusion of Li‐TFSI/t‐BP additive, we could fabricate more efficient mesoscopic MAPbI3 perovskite solar cells with smaller hysteresis with respect to scan direction due to Li mediated additional hole conduction. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
117.
Dr. Lubna Ghani Dr. Seonghoon Kim Dr. Haoqing Wang Hyun Sung Lee Dr. Jonas S. Mortensen Dr. Satoshi Katsube Dr. Yang Du Dr. Aiman Sadaf Dr. Waqar Ahmed Prof. Bernadette Byrne Prof. Lan Guan Prof. Claus J. Loland Prof. Brian K. Kobilka Prof. Wonpil Im Prof. Pil Seok Chae 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(21):e202200116
Membrane proteins are of biological and pharmaceutical significance. However, their structural study is extremely challenging mainly due to the fact that only a small number of chemical tools are suitable for stabilizing membrane proteins in solution. Detergents are widely used in membrane protein study, but conventional detergents are generally poor at stabilizing challenging membrane proteins such as G protein-coupled receptors and protein complexes. In the current study, we prepared tandem triazine-based maltosides (TZMs) with two amphiphilic triazine units connected by different diamine linkers, hydrazine (TZM−Hs) and 1,2-ethylenediamine (TZM−Es). These TZMs were consistently superior to a gold standard detergent (DDM) in terms of stabilizing a few membrane proteins. In addition, the TZM−Es containing a long linker showed more general protein stabilization efficacy with multiple membrane proteins than the TZM−Hs containing a short linker. This result indicates that introduction of the flexible1,2-ethylenediamine linker between two rigid triazine rings enables the TZM−Es to fold into favourable conformations in order to promote membrane protein stability. The novel concept of detergent foldability introduced in the current study has potential in rational detergent design and membrane protein applications. 相似文献
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119.
Sun Joo KimTae Hong Jeon Im Sook MinIn Su Kim Young Hoon Jung 《Tetrahedron letters》2012,53(28):3680-3682
A concise asymmetric total synthesis of (S)-dapoxetine from commercially available 3-chloropropiophenone is described. The key step includes a highly stereoselective amination of chiral benzylic ether, with the retention of stereochemistry, using chlorosulfonyl isocyanate. 相似文献
120.