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排序方式: 共有237条查询结果,搜索用时 328 毫秒
51.
Hatice Kaplan Can 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(1):26-33
The binary copolymerization of maleic anhydride (MA) and N-vinyl caprolactam (VCL) or considered as acceptor (A)?donor (D) monomer systems were used (MA:VCL) 50:50 in BPO (0.5%) as an initiator at 70°C under nitrogen atmosphere. The functional copolymers, having a combination of rigid/flexible linkages and an ability of complex-formation with interlayered surface of organo-silicate, and their nanocomposites have been synthesized. Interlamellar in situ complex-radical copolymerization of intercalated monomer complexes of MA and VCL undergoes with stearyl amine surface modified montmorillonite (O-MMT) and monomer mixtures. Charge transfer complex formation was followed and identified by UV-Vis-NIR spectroscopy. Equilibrium constant (KAD) molar absorption coefficient (?AD)) of the complex were determined by the Benesi-Hildebrand, Scott and Ketaalar equations respectively. The results show that copolymerization of MA:VCL system was preceded via alternating copolymerization mechanism. Obtained functional alternating copolymer and copolymer/O-MMT nanostructures were characterized by XRD and TEM. 相似文献
52.
Murat Ates 《Journal of Solid State Electrochemistry》2016,20(6):1509-1526
This review article investigates the hot topics by presenting the latest advances on graphene-based nanostructures for supercapacitors. In literature, many scientists have studied the nanomaterials and combination of conducting polymers in supercapacitor (SC) devices. The main aim of this review article is to present the higher capacitance, and higher power and energy density performances of the SC devices, which includes the active materials of carbon-based materials, metal oxides, conducting polymers, nanocomposites, etc. Many conventional techniques have already been used such as photolithography, inkjet printing, etc. Each of these methods has specific advantages and some drawbacks, with some working better in different environments. Among various nanoscaled materials, nanocrystal oxides of transition metals play an important role in advanced materials development. In addition to design of active material, symmetric and asymmetric supercapacitor device fabrication is also directly effect to obtain a higher capacitance, energy and power density performances. Therefore, this review article focuses on supercapacitor technology in new developments, such as design of active materials, device fabrication, etc. 相似文献
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U. Ceren Başköse Sevgi Haman Bayarı Semran Sağlam Hacı Özışık 《Central European Journal of Chemistry》2012,10(2):395-406
The conformational analysis of rasagiline [N-propargyl-1(R)-aminoindan] was performed by the density functional theory (DFT) B3LYP method using the 6–31++G (d,p) basis set. A single
point energy calculations based on the B3LYP optimized geometries were also performed at MP2/6-31++G (d, p) level. The vibrational
frequencies of the most stable conformer of rasagiline was calculated at the B3LYP level and vibrational assignments were
made for normal modes on the basis of scaled quantum mechanical force field (SQM) method. The influence of mesylate and ethanedisulfonate
salts on the geometry of rasagiline free base and its normal modes are also discussed.
相似文献
56.
The present study was conducted to investigate the contribution of conceptual change texts accompanied by concept mapping instruction to 10th— grade students' understanding of the human circulatory system. To determine misconceptions concerning the human circulatory system, 10 eleventh-grade students were interviewed. In the light of the findings obtained from student interviews and related literature, the Human Circulatory System Concepts Test was developed. The data were obtained from 26 students in the experimental group taught with the conceptual change texts accompanied by concept mapping, and 23 students in the control group taught with the traditional instruction. Besides treatment, previous learning in biology and science process skills were other independent variables involved in this study. Multiple Regression Correlation analysis revealed that science process skill, the treatment, and previous learning in biology each made a statistically significant contribution to the variation in students' understanding of the human circulatory system. It was found that the conceptual change texts accompanied by concept mapping instruction produced a positive effect on students' understanding of concepts. The mean scores of experimental and control groups showed that students in the experimental group performed better with respect to the human circulatory system. Item analysis was carried out to determine and compare the proportion of correct responses and misconceptions of students in both groups. The average percent of correct responses of the experimental group was 59.8%, and that of the control group was 51.6% after treatment. 相似文献
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The aim of this study is to efficiently utilize catalytic properties of silver nanoparticles and nitrogen doped graphene and their combined synergistic effect. For this purpose, nitrogen doped reduced graphene oxide-silver (NrGO-Ag) nanocomposites were synthesized by a facile, environmentally friendly, one-pot hydrothermal method for the first time and characterized by UV–Vis, FTIR, XRD, XPS, SEM, and TEM. Catalytic activity of the synthesized nanocomposites was tested against 4-nitrophenol (4-NP) and methylene blue (MB) reduction reactions in the presence of NaBH4. Total degradation was achieved in both reactions in 210 and 44 s, and pseudo first order reaction rate constants were calculated as 0.0071 and 0.0322 s−1 for 4-NP and MB reduction reactions, respectively. 相似文献
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Transition Metal Chemistry - New double-armed benzo-15-crown-5 compound (L) was successfully synthesized from 4’,5’-bis(bromethyl)benzo-15-crown-5 with 2,2’-dipyridylamine. The... 相似文献