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991.
The dynamic mechanical behavior and structural characteristics of polymerization bis(4-(4-ethynylphenoxy)phenyl)sulfine(ESF) and its polymers were investigated by means of tcrsional braid analysis(TBA) and infrared spectroscopy.Results show that the multiple transitions including the melting,low-temperature and high-temperature reactions of ESF oligomers,glass transition and decomposition reaction of resulted polymer can be characterized in the TBA spectra.The glass transition tempe: atures and structural characteristics of ESF polymers depend upon the conditions of polymerization. 相似文献
992.
993.
Zhi-Hao Yu Xingshu Li Dr. Fugui Xu Xi-Le Hu Dr. Jiatao Yan Nahyun Kwon Guo-Rong Chen Dr. Tingting Tang Dr. Xiaojing Dong Prof. Yiyong Mai Prof. Daijie Chen Prof. Juyoung Yoon Prof. Xiao-Peng He Prof. He Tian 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3687-3693
With the ever-increasing threat posed by the multi-drug resistance of bacteria, the development of non-antibiotic agents for the broad-spectrum eradication of clinically prevalent superbugs remains a global challenge. Here, we demonstrate the simple supramolecular self-assembly of structurally defined graphene nanoribbons (GNRs) with a cationic porphyrin (Pp4N) to afford unique one-dimensional wire-like GNR superstructures coated with Pp4N nanoparticles. This Pp4N/GNR nanocomposite displays excellent dual-modal properties with significant reactive-oxygen-species (ROS) production (in photodynamic therapy) and temperature elevation (in photothermal therapy) upon light irradiation at 660 and 808 nm, respectively. This combined approach proved synergistic, providing an impressive antimicrobial effect that led to the complete annihilation of a wide spectrum of Gram-positive, Gram-negative, and drug-resistant bacteria both in vitro and in vivo. The study also unveils the promise of GNRs as a new platform to develop dual-modal antimicrobial agents that are able to overcome antibiotic resistance. 相似文献
994.
Pengfei Zhang Dr. Chunyang Yu Yucheng Yin Jörn Droste Sina Klabunde Prof. Michael Ryan Hansen Prof. Yiyong Mai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16497-16503
Development of high-performance photocatalysts for the conversion of amines is of great importance, but has remained a challenging task. Here, a bis-anthracene fused porphyrin ( AFP ) was synthesized in a high yield by a facile synthetic protocol, which involves a Suzuki coupling for the conjugation of two anthracene groups with a porphyrin ring, followed by oxidative cyclodehydrogenation. When serving as a photocatalyst, AFP exhibits an outstanding photocatalytic performance for the visible-light-induced aerobic oxidation of amines to imines at ambient conditions. Density functional theory calculations revealed that the low energy band gap, caused by the large planar and π-extended porphyrin structure of AFP , contributed to its high photocatalytic performance. 相似文献
995.
Mai Tsubamoto Toan Khanh Le Dr. Minghua Li Dr. Taku Watanabe Dr. Chiemi Matsumi Dr. Prakash Parvatkar Prof. Dr. Hiroshi Fujii Prof. Dr. Nobuo Kato Prof. Dr. Jiazhi Sun Prof. Dr. Junko Ohkanda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(59):13531-13536
Unusual lipid modification of K-Ras makes Ras-directed cancer therapy a challenging task. Aiming to disrupt electrostatic-driven protein–protein interactions (PPIs) of K-Ras with FTase and GGTase I, a series of bivalent dual inhibitors that recognize the active pocket and the common acidic surface of FTase and GGTase I were designed. The structure-activity-relationship study resulted in 8 b , in which a biphenyl-based peptidomimetic FTI-277 was attached to a guanidyl-containing gallate moiety through an alkyl linker. Cell-based evaluation demonstrated that 8 b exhibited substantial inhibition of K-Ras processing without apparent interference with Rap-1A processing. Fluorescent imaging showed that 8 b disrupts localization of K-Ras to the plasma membrane and impairs interaction with c-Raf, whereas only FTI-277 was found to be inactive. These results suggest that targeting the PPI interface of K-Ras may provide an alternative method of inhibiting K-Ras. 相似文献
996.
Quyen Vu Thi Minh Le Thi Hong Huyen Vu Thi Thu Anh Nguyen Mai Hue Nguyen Thi Dao Phi Thi Linh Nguyen Thuy Van Cuong Pham Huong Doan Thi Mai 《Chemistry of Natural Compounds》2022,58(4):704-707
Chemistry of Natural Compounds - Analysis of an antimicrobial extract prepared from the culture broth of the marine-derived actinomycete Nocardiopsis synnemataformans (HT06 strain) led to the... 相似文献
997.
Zhang Xiaoxue Årstøl Erland Nymark Marianne Fages-Lartaud Maxime Mikkelsen Øyvind 《Journal of Cluster Science》2022,33(6):2407-2417
Journal of Cluster Science - The development of antifouling coating for sensor is desirable because the biofilm can shorten sensor’s life and cause inaccurate reading. In this study, a facile... 相似文献
998.
Li Guoqiang Li Jin Cui Qian Mai Wanshan Zhang Ziqiong Zhang Kaikai Nie Renfeng Hu Wei 《Journal of Solid State Electrochemistry》2020,24(10):2427-2439
Journal of Solid State Electrochemistry - For the rational design of heteroatom-doping carbon catalysts toward the oxygen reduction reaction (ORR), various structure-wise and porous... 相似文献
999.
Mechanism and kinetics of the thermal pyrolysis of ethyl 2-furoate were studied in a wide range of conditions (ie, 500-1500 K and 1-7600 Torr) using the accurate dual-level theory CCSD(T)&MP2(FC)//B3LYP/aug-cc-pVTZ and state-of-the-art Rice-Ramsperger-Kassel-Marcus based master equation rate model including hindered internal rotation and tunneling treatments. The predicted rate coefficients are found to be in accordance with the experimental data. The mechanism details are revealed as (i) the major decomposition channel occurs via a six-center transition state with the barrier energy of 48.3 kcal/mol at 0 K, leading to the formation of C2H4 and 2-furoic acid and (ii) pressure has a slightly positive effect on the rate constant, particularly at the high temperature. Also, the reactivity of ethyl 2-furoate toward OH radicals was discussed in the first place. 相似文献
1000.
Shasha Li Jianping Pan Xiaoxue Wu Yanghe Fu Qiang Xiao Fumin Zhang Weidong Zhu 《应用有机金属化学》2019,33(12)
Metal–organic frameworks (MOFs) have recently been identified as versatile sacrificing templates to construct functional nanomaterials for heterogeneous catalysis. Herein, we report a thermal transformation strategy to directly fabricate metal Pd nanoclusters inlaid within a ZrO2@nitrogen‐doped porous carbon (Pd/ZrO2@CN) composite using Pd@NH2‐UiO‐66(Zr) as a precursor that was pre‐synthesized by a one‐pot hydrothermal method. The developed Pd/ZrO2@CN as a robust catalyst delivered remarkable stability and activity to the catalytic hydrogenation of 2,3,5‐trimethylbenzoquinone (TMBQ) to 2,3,5‐trimethylhydroquinone (TMHQ), a key reaction involved in vitamin E production. The hydrogenation was carried out at 110 °C with 1.0 MPa H2, and it resulted in 98% TMHQ yield as the sole product over five consecutive cycles, outperforming the analogue Pd/ZrO2@C without nitrogen doping templated from Pd@UiO‐66(Zr). The excellent catalytic properties of Pd/ZrO2@CN likely originated from the highly stable ultrafine Pd nanoclusters inlaid within ZrO2@CN matrix on account of the strong interaction between N and Pd, as well as on the Lewis acidity of ZrO2, which was beneficial to the hydrogenation. 相似文献