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The self-assembly of Oxi-SWNTs, based on terpyridineCu(II) coordination, produces a thermally stable, neutral [(Oxi-SWNT)(tpyCu(II))m]n nanocomposite possessing notable luminscence properties; quantitative disassembly occurred by treatment with aqueous KCN.

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Reasonable control of the pore sizes of supercapacitor electrode materials ensures the desolvation of electrolyte ions to significantly improve the capacitance.

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Lithium-sulfur (Li-S) batteries have attracted increasing attention due to their high theoretical capacity, being a promising candidate for portable electronics, electric vehicles and large-scale energy storage. The interactions of bilayer structured graphitic CN (bi-CN) with S, lithium polysulfides (LiPSs), 1,3-dioxolane, 1,2-dimethoxyethane and tetrahydrofuran ether-based solvents have been studied using first-principles calculations. It has been found that the (micropore-scale) interlayer of bi-CN shows intimate contact and strong binding with S and LiPSs due to the formation of chemical Li-N bonds. The incorporation of soluble LiPSs by the wrinkled layers of bi-CN with 5.5-7.2 Å interlayer pores can suppress the shuttling effect. The interlayer ultramicropores with interlayer distances of <4 Å can accommodate the small LiS and LiS molecules, and impede the irreversible reaction between the solvents and the LiPSs. The calculated energy gap of bi-CN decreases to be narrow during lithiation. Our results can provide a guideline for promoting the electrochemical performance of microporous g-CN/sulfur composites for Li-S batteries.

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Shear wave propagation provides rich information for material mechanical characterization, including elasticity and viscosity. This Letter reports tracking of shear wave propagation in turbid media by laser-speckle-contrast analysis. The theory is described, and a Monte Carlo simulation of light shear wave interaction was developed. Simulation and experiments on tissue-mimicking phantoms agree well and show tracking of shear wave at the phantom surface and at depth as well as multiple shear waves interacting within the object. The relationship between speckle contrast value and shear wave amplitude is also investigated. . Optical observation of tissue response to acoustic radiation force and associated shear wave generation was previously reported in [4,5]. In this Letter, we present a method to track the shear wave propagation in optically turbid media by laser speckle contrast analysis. Part of our experimental method was discussed in [6], where the shear wave speed was tracked in phantoms of varying elasticity. A coherent green laser was used, and the speckle patterns were received on a CCD camera. Transient shear waves were generated by acoustic radiation force a distance away from laser axis at depth in phantoms. The shear wave was tracked using the timeresolved CCD speckle-contrast difference. In this Letter, we first describe the theoretical basis of this experimental method, then a Monte Carlo simulation system is developed for the first time and verified by experiments. We also show shear wave imaging at the phantom edge using local speckle contrast analysis. In addition, multiple shear waves are simultaneously observed through speckle-contrast detection for the first time, and the relationship between CCD speckle-contrast difference and shear wave amplitude is also studied.Previous theoretical contributions that explain the interaction of ultrasound and (multiply) scattered light are available in the literature [7][8][9]. Generally, two mechanisms are thought to be responsible for the ultrasound modulation of light: first, the phase change due to displacement of optical scatterers by ultrasound; second, the phase change due to alteration of the optical refractive index by compression and rarefaction of ultrasound. However, when light interacts with a transient shear wave alone, there are two major differences: (1) the shear wave pressure is small, and therefore little alteration of optical refractive index occurs. As a consequence, the second modulation mechanism may be neglected; (2) the shear wave period is much longer than the ultrasound period and is comparable and most likely longer than the light integration time on the detector. Below we describe a framework that can be used to explain the mechanism of tracking shear waves with CCD speckle-contrast analysis.A stochastic explanation of CCD speckle analysis was provided [10,11]. The CCD speckle contrast is defined by C σ∕Ī, where σ andĪ are the standard deviation and the mean of CCD pixel intensities. From first-and second-order statistical analys...