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Dandan Guo Xiaowei Liu Aolin Zhang Mengnan Ruan Zhifeng Liu Zhe Wang 《Journal of polymer science. Part A, Polymer chemistry》2024,62(3):536-546
Dielectric elastomers (DEs) require high drive voltages to obtain large actuated strain, which limits their application in the biological field. In this work, we enhanced the dielectric properties of natural rubber (NR) composites by using core–shell structured (CaCu3Ti4O12)x@(BaTiO3)(1−x) (CCTOx@BT(1−x)) high-dielectric particles with an buffer layer, and adjusted the thickness of the BT buffer layer by adjusting the addition of titanate during the preparation process, and then observed the relationship between the dielectric properties of NR composites and the thickness of the BT buffer layer. In addition, we modified the CCTO0.75@BT0.25 fillers surface with silane coupling agent KH560 to enhance the interfacial interaction between the inorganic fillers and polymeric matrix to obtain better dispersion and greater dielectric properties. As a result of the optimization of the CCTO0.75@BT0.25@KH560 structure, the actuated strain performance is greatly improved. The actuated strain of 5 per hundred rubber (phr) CCTO0.75@BT0.25@KH560/NR is 16.3% at 74.03 kV/mm, which is 6.52 times higher than the actuated strain obtained by NR (2.5%) at 50.28 kV/mm. This work presents a method to optimize the structure of core–shell fillers by modulating the buffer layer, and provides a new idea for further preparation of dielectric elastomer materials with large actuated strain at low voltage. 相似文献
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Determination of Thermal History by Photoluminescence of Core‐Shelled Quantum Dots Going Through Heating Events 下载免费PDF全文
Yucheng Lan Hui Wang Nitin Skula Xiaoyuan Chen Yalin Lu Gang Chen Zhifeng Ren 《Particle & Particle Systems Characterization》2015,32(1):65-71
A kind of novel thermal history nanosensors are theoretically designed and experimentally demonstrated to permanently record thermal events. The photoluminescence (PL) spectrum of core‐shelled quantum dots (QDs) CdSe/ZnS irreversibly shifts with heating histories (temperature and duration) of thermal events. The induced PL shift of the QDs CdSe/ZnS is employed to permanently record thermal histories. We further model a kind of thermal history nanosensor based on the thermal‐induced phenomena of core‐shelled QDs to permanently record thermal histories at microscale and demonstrate to reconstruct temperature and duration of heating events simultaneously from PL spectra of the QDs. The physical mechanism of the sensors is discussed. 相似文献
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文章对5种碳五位(C5)的不同取代基海因的质子北合能(PA),在亚稳状态下采用“动能法”进行了研究。以5,5-甲基海因作为参照,确定了5种样品亲质子能的顺序。 相似文献
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Kim SN Kuang Z Slocik JM Jones SE Cui Y Farmer BL McAlpine MC Naik RR 《Journal of the American Chemical Society》2011,133(37):14480-14483
Peptides identified from combinatorial peptide libraries have been shown to bind to a variety of abiotic surfaces. Biotic-abiotic interactions can be exploited to create hybrid materials with interesting electronic, optical, or catalytic properties. Here we show that peptides identified from a combinatorial phage display peptide library assemble preferentially to the edge or planar surface of graphene and can affect the electronic properties of graphene. Molecular dynamics simulations and experiments provide insight into the mechanism of peptide binding to the graphene edge. 相似文献
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A novel and sensitive chemiluminescence (CL) method for the determination of aminomethylbenzoic acid and aminophylline coupled with flow-injection analysis (FIA) technique is developed in this paper. It is based on the inhibition effect of the studied drugs on the chemiluminescence emission of N-bromosuccinimide-luminol (NBS-luminol) system. Under the optimum conditions, the decreased CL intensity is linear with the concentration of aminomethylbenzoic acid in the range of 2×10−8 to 1.0×10−6 g ml−1 and with the concentration of aminophylline in the range of 1×10−7 to 7.0×10−6 g ml−1, respectively. The detection limit is 7.0×10−9 g ml−1 for aminomethylbenzoic acid (3σ) and 3.4×10−8 g ml−1 for aminophylline (3σ). The relative standard deviations (R.S.D.) for 11 parallel measurements of 2.0×10−7 g ml−1 aminomethylbenzoic acid and 1.0×10−6 g ml−1 aminophylline are 2.6 and 3.0%, respectively. The proposed methods have been applied for the determination of the studied drugs in their pharmaceutical formulations with satisfactory results. The possible use of the proposed system for the determination of aminomethylbenzoic acid in plasma sample was also tested. The possible inhibition mechanism of aminomethylbenzoic acid and aminophylline on luminol-NBS system was discussed briefly. 相似文献
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Luminol-type compounds can be used as chemiluminescent (CL) derivatization reagents for amines, carboxylic acids and protein. Copper chelate diperiodatocuprate(III) (K5[Cu(HIO6)2], DPC) was synthesized by complexation of copper at trivalent oxidation state and periodate in a strong basic medium. It was found that DPC can greatly enhance the reaction between luminol-type compounds and H2O2 to produce very strong CL emission. Based on this fact, a rapid CE method combined with high-sensitive end-column CL detection was established to simultaneously analyze luminol and N-(4-aminobutyl)-N-ethylisoluminol (ABEI) with wide concentration range of 3.0-300 nmol/L in 5 min. The RSDs of the signal intensity and the migration time were less than 3.9 and 7.0% for a standard sample containing 100 nmol/L luminol and ABEI (n=5), respectively. The investigation implies that DPC is a promising sensitizer for CE-CL detection of a great variety of biomolecules and drugs in biological samples after derivatization using luminol derivatives. 相似文献
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The highly enantioselective Michael addition of malonates to α,β-unsaturated ketones in water was reported to be catalyzed by a primary-secondary diamine catalyst containing a long alkyl chain. This asymmetric Michael addition process was found to be effective for a variety of α,β-unsaturated ketones. 相似文献