纳米团簇的超分子自组装

在纳米材料的应用过程中, 纳米团簇或纳米粒子的组装将是非常关键的一步。纳米团簇的超分子化学组装方法可分为两类, 即胶态晶体法和模板法。胶态晶体法是利用胶体溶液的自组装特性将纳米团簇组装成超晶格, 可得到二维或三维有序的超晶格。模板法是利用纳米团簇与组装模板间的识别作用来带动团簇的组装, 可应用的模板有固体膜、单分子膜、有机分子、生物分子等。其中, 单分子膜模板是研究最多也是最为成熟的一种; 生物分子间严密的分子识别功能使其成为非常有发展前途的组装模板, 而且用生物分子模板有可能实现不同纳米团簇间的组装。     

Efficient Electroluminescence from Excimers of 1,3,6,8‐Tetrakis(3,5‐dimethylphenyl)pyrene

Excimers are generally considered as detrimental to OLEDs. For pyrene‐based chromophores, however, this is not always true. In this contribution, two new methylated tetraphenylpyrenes, 1,3,6,8‐tetra‐o‐tolylpyrene (TTPy) and 1,3,6,8‐tetrakis(3,5‐dimethylphenyl)pyrene (TDMPPy), were synthesized through Suzuki coupling reactions. TDMPPy absorbs and emits light at longer wavelengths than TTPy due to its more planar conformation and thus better conjugation. TDMPPy is prone to excimer formation, thus leading to a strong bathochromic shift (84 nm) in the photoluminescence spectrum of its film. TDMPPy exhibits efficient electroluminescence originating from pyrene excimers, affording a maximum luminance of 26 670 cd m^?2 and a current efficiency as high as 10.8 cd A^?1 in a non‐doped OLED (ITO/PEDOT:PSS (50 nm)/NPB (30 nm)/TDMPPy (30 nm)/TPBI (40 nm)/Ca:Ag).     

Bi‐Directional Electrocatalytic Detection of Dopamine at an Electrode Modified with Ferrocene‐Filled Carbon Nanotube Peapods

A glassy carbon electrode (GCE) was modified with nanopeapods formed by ferrocene filled single‐walled carbon nanotubes (Fc@SWNTs). The modified electrode showed bi‐directional electrocatalysis toward dopamine (DA), which suggested a synergistic effect of ferrocene and carbon nanotubes. Bi‐directional detection of DA was realized based on the modified electrode.     

Components reduction regularity results for the Navier–Stokes equations in general dimensions

We consider the Cauchy problem of the Navier–Stokes equations in arbitrary dimensions, and establish several new components reduction regularity criteria.     

Global regularity criterion for the Navier‐Stokes equations based on the direction of vorticity

We study the regularity criterion for the Navier‐Stokes equations and show that the (β₁,β₂,β₃)‐Hölder continuity assumption in (x₁,x₂,x₃) on the direction of the vorticity ensures the regularity of the solution. This may be viewed as an extension of many previous results, since some of the β_i can be arbitrarily small.     

Novel, yellow-emitting anthracene/fluorene oligomers: synthesis and characterization

A novel series of highly soluble and strongly yellow fluorescent with well-controlled, alternative anthracene, and fluorene units were successfully synthesized by a Pd/Cu-catalyzed Sonogashira coupling reaction and characterized. Their thermal stabilities, electrochemical behaviors, and photophysical properties were investigated. These oligomers might be used as models to study structure-property relationship for their corresponding polymers and applied in optoelectronics devices as materials themselves.     

Achieving Efficient Multichannel Conductance in Through-Space Conjugated Single-Molecule Parallel Circuits

Constructing single-molecule parallel circuits with multiple conduction channels is an effective strategy to improve the conductance of a single molecular junction, but rarely reported. We present a novel through-space conjugated single-molecule parallel circuit (f-4Ph-4SMe) comprised of a pair of closely parallelly aligned p-quaterphenyl chains tethered by a vinyl bridge and end-capped with four SMe anchoring groups. Scanning-tunneling-microscopy-based break junction (STM-BJ) and transmission calculations demonstrate that f-4Ph-4SMe holds multiple conductance states owing to different contact configurations. When four SMe groups are in contact with two electrodes at the same time, the through-bond and through-space conduction channels work synergistically, resulting in a conductance much larger than those of analogous molecules with two SMe groups or the sum of two p-quaterphenyl chains. The system is an ideal model for understanding electron transport through parallel π-stacked molecular systems and may serve as a key component for integrated molecular circuits with controllable conductance.     

Serrin-type regularity criterion for the Navier-Stokes equations involving one velocity and one vorticity component

We consider the Cauchy problem for the three-dimensional Navier-Stokes equations, and provide an optimal regularity criterion in terms of u₃ and ω₃, which are the third components of the velocity and vorticity, respectively. This gives an affirmative answer to an open problem in the paper by P. Penel, M.Pokorný (2004).