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Rhenium diselenide (ReSe2) has attracted great interest due to its unique anisotropic structure and unusual in-plane anisotropic electrical and optical properties. However, efficient fabrication of large-area and high-quality 2D ReSe2 continuous films has become an increasingly important challenge. In this work, centimeter-scale 2D ReSe2 continuous films with the layer number varying from monolayer to 12 layers were successfully grown on a mica substrate using our space-confined CVD system via changing the position of the substrate. The fluorescence quenching effect and surface enhanced Raman scattering (SERS) effect on 2D ReSe2 films with different layer numbers were investigated using rhodamine 6G (R6G) dye molecules as a Raman probe. The large-area ReSe2 films show the layer-number-dependent nature of the SERS effect and a robust suppression effect of fluorescence. Our work explores the practical application of 2D ReSe2 films for molecular detection via the SERS technique. [ABSTRACT FROM AUTHOR]

This paper presents two hybrid strategies for robot visual servoing. Two specific image constraints, the image singularities and image local minima, are considered in both strategies. The hybrid motion control strategy consists of a local switching control between the image-based and position-based visual servoing for direct avoidance of image singularities and image local minima. The hybrid motion planning strategy consists of an artificial potential field-based global hybrid trajectory planner, where a complete set of Cartesian, image, and robot joint constraints under a complex visual servoing scenario are considered. In this strategy, the image singularities are resolved using the damped-least-square-based joint trajectory planning, while the image local minima are evaluated only along the planned image trajectories and automatically avoided in the image-based trajectory tracking. Two global planning methods are considered. In the first method, the end-effector trajectory is directly planned with respect to the stationary target object frame, which provides a much shorter translational path compared with the local planning method. In the second method, the target trajectory is planned with respect to the current end-effector frame, which minimizes the chances of image trajectories leaving the camera field of view. Simulation and experimental results are given to demonstrate the efficiency of the two hybrid strategies. Index Terms--Artificial potential field, switching control, trajectory planning, visual servoing.

In this study, the controlled-layer and large-area two-dimensional (2D) rhenium disulfide (ReS2) thin films were grown on mica substrates by chemical vapor deposition method using S powder and Re-Te powder as starting materials. The morphology, thickness and crystallographic structure of 2D ReS2 thin films were investigated using optical microscope (OM), field emission scanning electronic microscope (SEM), atomic force microscopy (AFM) and Raman spectroscopy, respectively. In order to study the layer-dependent electrical transport property of 2D ReS2 thin films, the back-gated field effect transistors (FETs) based on 2D ReS2 thin films with different layer number and different channel lengths were prepared. The dependence relationship between carrier mobility and layer number of 2D ReS2 thin films were studied and discussed. Results show that the controlled-layer and substrate-scale ReS2 thin films can be grown on mica substrate at temperature of 650 °C. The layer number of 2D ReS2 thin films can be adjusted from 1 to 10 layers by changing the location of the substrate. The carrier mobility of 2D ReS2 thin films increases with an increasing number of layers (from 1 to 5 layers) and to be saturated when further increase the number of layers. [ABSTRACT FROM AUTHOR]

Abstract: The presented contribution aims at investigating the role of nano-TiO2 dispersibility in affecting the performance of PVDF-HFP based composite polymer electrolytes (CPEs) for Li-ion cells. Four types of polymer electrolytes containing pristine PVDF-HFP gel polymer electrolyte (GPE), PVDF-HFP/nano-TiO2 CPE, PVDF-HFP/nano-TiO2-PMMA CPE and PVDF-HFP/high-dispersed nano-TiO2-PMMA CPE membranes are obtained by phase inversion. The effect of nano-TiO2 dispersibility on performances of PVDF-HFP based CPEs in terms of ionic conductivity, C-rate and cycling performance is investigated. The results demonstrate that the dispersibility of nano-TiO2 is a key factor to affect the performance of PVDF-HFP based CPEs, and the improvement of the dispersibility of nano-TiO2 can remarkably enhance the electrochemical performances of cells assembled with the corresponding CPEs. [Copyright &y& Elsevier]

Rhenium diselenide (ReSe 2 ) has attracted great interest due to its unique anisotropic structure and unusual in-plane anisotropic electrical and optical properties. However, efficient fabrication of large-area and high-quality 2D ReSe 2 continuous films has become an increasingly important challenge. In this work, centimeter-scale 2D ReSe 2 continuous films with the layer number varying from monolayer to 12 layers were successfully grown on a mica substrate using our space-confined CVD system via changing the position of the substrate. The fluorescence quenching effect and surface enhanced Raman scattering (SERS) effect on 2D ReSe 2 films with different layer numbers were investigated using rhodamine 6G (R6G) dye molecules as a Raman probe. The large-area ReSe 2 films show the layer-number-dependent nature of the SERS effect and a robust suppression effect of fluorescence. Our work explores the practical application of 2D ReSe 2 films for molecular detection via the SERS technique.

We proposed an approach to precisely control the density of tethered chains on solid substrates using PEO-b-PS and PLLA-b-PS. As the crystallization temperature Tx increased, the PEO or PLLA lamellar crystal thickness d(L) increased as well as the reduced tethering density sigma; of the PS chains. The onset of tethered PS chains overcrowding in solution occurs at sigma(*) approximately 3.7-3.8 as evidenced by an abrupt change in the slope between (d(L))(-1) and Tx. This results from the extra surface free energy created by the tethered chain that starts to affect the growth barrier of the crystalline blocks.