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71.
Graphene composites with metal or metal oxide nanoparticles have been extensively investigated owing to their potential applications in the fields of fuel cells, batteries, sensing, solar cells, and catalysis. Among them, much research has focused on supercapacitor applications and have come close to realization. Composites include monometal oxides of cobalt, nickel, manganese, and iron, as well as their binary and ternary oxides. In addition, their morphological control and hybrid systems of carbon nanotubes have also been investigated. This review presents the current trends in research on metal oxide/graphene composites for supercapacitors. Furthermore, methods are suggested to improve the properties of electrochemical capacitor electrodes. 相似文献
72.
Molecular Orbital Controlling Donor Moiety for High‐Efficiency Thermally Activated Delayed Fluorescent Emitters 下载免费PDF全文
A new donor moiety, 7,7,13,13‐tetramethyl‐7,13‐dihydro‐5H‐indeno[1,2‐b]acridine (IAc), was developed to control the highest occupied molecular orbital (HOMO) dispersion of thermally activated delayed fluorescent (TADF) emitters. The IAc unit expanded the HOMO dispersion of the emitters and increased the quantum efficiency of the TADF devices up to 20.9 %. 相似文献
73.
[reaction: see text] The enantioselective synthesis of (-)-belactosin C and derivatives was accomplished in a concise manner employing the tandem, Mukaiyama aldol-lactonizaton (TMAL) process. One approach involved a distal double diastereoselective TMAL reaction with a dipeptide glyoxamide, whereas a second approach involved amide coupling of a dipeptide with a beta-lactone carboxylic acid, obtained via the TMAL process employing a chiral silyl ketene acetal. Notable improvements in diastereoselectivity were achieved in a proximal double diastereoselective TMAL process. 相似文献
74.
The combinatorial fluorescent dapoxyl dye library was prepared by both solution- and solid-phase synthesis, generating 80 unique dapoxyl derivatives. A fluorescence-based screening toward human serum albumin (HSA) found one highly sensitive HSA binder ( A41-S) with over 55-fold intensity change. Displacement assay showed the selective binding of A41-S to the site I of HSA, addressing its potential to be a highly selective and sensitive HSA probe. 相似文献
75.
Adsorption of cephalosporin C in a column charged with a nonionic polymeric sorbent, SP850, was studied at various pH values to assess the effect of pH on the dynamic behavior in column adsorbers. Since cephalosporin C is amphoteric, the fractions of each ionic form were calculated from the pK values at a given solution pH. Single-species isotherm parameters for each ionic form were simultaneously extracted from all sets of adsorption equilibrium data measured at several pH values. The mutual interaction between different ionic forms on SP850 was described by a competitive adsorption, namely the ideal adsorbed solution theory (IAST). This treatment made it possible to simulate the dynamic behavior of cephalosporin C at low pH values properly by a dynamic model which was incorporated with the mutual competitive adsorption. 相似文献
76.
Sang‐Wook Park Seung‐Hyeun Park Wonho Kim Dong‐Soo Suh In‐Joe Sohn 《Journal of polymer science. Part A, Polymer chemistry》2000,38(19):3543-3549
The phase‐transfer catalyzed graft copolymerization of methyl methacrylate onto polychloroprene was carried out using tricaprylylmethylammonium chloride as a phase‐transfer catalyst in a two‐phase system of an aqueous Na2S2O8 solution and toluene at 55 °C under a nitrogen atmosphere. The initial rate of graft copolymerization was expressed as the combined terms of quaternary onium cation and peroxydisulfate anion in the aqueous phase rather than the fed concentrations of catalyst and Na2S2O8. The observed initial rate of graft copolymerization was used to analyze the graft copolymerization mechanism with a cycle phase‐transfer initiation step in the heterogeneous liquid–liquid system. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3543–3549, 2000 相似文献
77.
78.
We report on the femtosecond laser micromachining of photo-induced embedded diffraction grating in flexible Poly (Dimethly Siloxane) (PDMS) plates using a high-intensity femtosecond (130 fs) Ti: sapphire laser (λp = 800 nm). The refractive index modifications with diameters ranging from 2 μm to 5 μm were photo-induced after the irradiation with peak intensities of more than 1 × 1011 W/cm2. The graded refractive index profile was fabricated to be a symmetric around from the center of the point at which femtosecond laser was focused. The maximum refractive index change (Δn) was estimated to be 2 × 10−3. By the X-Y-Z scanning of sample, the embedded diffraction grating in PDMS plate was fabricated successfully using a femtosecond laser. 相似文献
79.
Sung‐Nak Choi Sang‐Yub Kim Hae‐Wook Ryu Yong‐Min Lee 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(12):m504-m506
In the title compound, [HgCl2(C15H26N2)], the chiral alkaloid (6R,7S,8S,14S)‐(−)‐l ‐sparteine acts as a bidentate ligand, with two Cl− ligands occupying the remaining coordination sites, producing a distorted tetrahedron. The N—Hg—N plane is twisted by 81.1 (2)° from the Cl—Hg—Cl plane. The mid‐point of the N⋯N line does not lie exactly on the Cl—Hg—Cl plane but is tilted towards one of the N atoms by 0.346 Å. Similarly, the mid‐point of the Cl⋯Cl line is tilted toward one of the Cl atoms by 0.163 Å. The packing structure shows that the complex is stabilized by two interatomic Cl⋯H contacts involving both Cl atoms and the methylene or methine H atoms of the (−)‐sparteine ligand. 相似文献
80.
Multi-branched gold nanoparticles were synthesized in high-yield through the reduction of HAuCl(4) by using hydrazine as a reducing agent. Practically 100% of the particles have numerous branches. The high reduction capability of hydrazine is found to be crucial for the formation of these branched gold nanoparticles. Their size can be controlled from 20 to 130 nm by varying the amounts of hydrazine. The prepared nanoparticles exhibit efficient surface-enhanced Raman scattering (SERS) properties and the SERS activity of the particles depends on the aspect ratio of their branches, which are most likely related to a great increase in the localized electromagnetic field enhancement from their unique sharp surface features arising from the branches. 相似文献