Activity-assisted barrier-crossing of self-propelled colloids over parallel microgrooves

We report a systematic study of the dynamics of self-propelled particles (SPPs) over a one-dimensional periodic potential landscape, which is fabricated on a microgroove-patterned polydimethylsiloxane (PDMS) substrate. From the measured non-equilibrium probability density function of the SPPs, we find that the escape dynamics of the slow-rotating SPPs across the potential landscape can be described by an effective potential, once the self-propulsion force is included into the potential under the fixed angle approximation. This work demonstrates that the parallel microgrooves provide a versatile platform for a quantitative understanding of the interplay among the self-propulsion force, spatial confinement by the potential landscape, and thermal noise, as well as its effects on activity-assisted escape dynamics and transport of the SPPs

Holey Silicon as an Efficient Thermoelectric Material

This work investigated the thermoelectric properties of thin silicon membranes that have been decorated with high density of nanoscopic holes. These ?holey silicon? (HS) structures were fabricated by either nanosphere or block-copolymer lithography, both of which are scalable for practical device application. By reducing the pitch of the hexagonal holey pattern down to 55 nm with 35percent porosity, the thermal conductivity of HS is consistently reduced by 2 orders of magnitude and approaches the amorphous limit. With a ZT value of 0.4 at room temperature, the thermoelectric performance of HS is comparable with the best value recorded in silicon nanowire system

Holey Silicon as an Efficient Thermoelectric Material

This work investigated the thermoelectric properties of thin silicon membranes that have been decorated with high density of nanoscopic holes. These ?holey silicon? (HS) structures were fabricated by either nanosphere or block-copolymer lithography, both of which are scalable for practical device application. By reducing the pitch of the hexagonal holey pattern down to 55 nm with 35percent porosity, the thermal conductivity of HS is consistently reduced by 2 orders of magnitude and approaches the amorphous limit. With a ZT value of 0.4 at room temperature, the thermoelectric performance of HS is comparable with the best value recorded in silicon nanowire system

Simple Electroosmotic Pump and Active Microfluidics with Asymmetrically Coated Microelectrodes

Electroosmotic pumps can deliver liquid without moving parts, making them suitable for microfluidic and lab‐on‐chip systems. Previously, alternating current electroosmotic pumps were constructed using pairs of coplanar asymmetrical interdigitated microelectrodes on the same substrate. In this work, a simpler micropumping system is developed, separating the electrodes on two substrates and breaking the symmetry by half‐depositing electrodes with 3D microstructures. Numerical simulation models of the pumping system and experimental velocity profiles are used to explain the fluid motion mechanism and structure‐dependent pumping performance. In addition to its efficiency and simplicity, this new pumping system also allows for the creation of a microvortex device and an active microfluidics device. This scalable micropumping system provides a way to pump liquids at microscopic or macroscopical scale in complex microfluidics systems

Molecular Engineering on Kinetics‐Driven Self‐Assembled Monolayers Working as Auxiliary Layers on Dielectrics in Organic Field‐Effect Transistors

Abstract Self‐assembled monolayers (SAMs) are a class of quasi‐2D materials adhesive to the substrate by chemisorption. Due to their transparency, diversity, stability, sensitivity, selectivity, and great potential in surface passivation, SAMs have been extensively investigated and applied in various functional devices, particularly in organic field effect transistors (OFETs). Among all the processing methods, kinetic‐driven spin‐coating is frequently used for the SAM preparation due to its high efficiency and low cost. However, the importance of SAM quality and its relationship to device performance has not been studied in detail, hindering the new SAM development and device optimization. In this study, SAMs prepared by kinetic‐driven spin‐coating are carefully investigated in terms of their surface morphology, density, and regularity, and proposed a correlation model between chemical structure and SAM quality. Additionally, the prepared SAMs are utilized as auxiliary layers on dielectrics and analyzed their effects on OFET properties. Through these investigations, a sequential relationship is established between chemical structure, SAM quality, and device performance, which can provide efficient feedback for system optimization

How Can the Sustainable Motivational Effect of Equity Incentives on Corporate Performance Be Exploited?—A Study Based on the Moderating Effect of Aspiration Level

How equity incentives affect corporate performance has become a consensus. However, the question of how to maximize the sustainable incentive effect of equity incentives on corporate performance and avoid “short-sighted” behavior under equity incentives has not yet been resolved. This research re-examines the sustainable incentive of equity incentives and examines the moderating role of aspiration levels based on the behavioral theory of the firm and the prospect theory. Applying panel data comprised 9588 observations from Chinese A-share listed companies spanning the period from 2011 to 2019, this study found that there is an inverted U-shaped relationship between equity incentives and corporate performance. Aspiration surplus negatively moderates the curvilinear inverted U-shaped relationship. As the level of aspiration surplus changes from low to high, the curvilinear relationship between equity incentives and corporate performance is weakened. Aspiration loss positively moderates the curvilinear inverted U-shaped relationship. As the level of aspiration loss changes from low to high, the curvilinear relationship between equity incentives and corporate performance is enhanced. This study demonstrates the importance of aspiration level between equity incentives and corporate performance, guiding firms to focus on the implementation scenario as an influencing factor in order to improve the sustainable incentive effect of equity incentives

How Can the Sustainable Motivational Effect of Equity Incentives on Corporate Performance Be Exploited?—A Study Based on the Moderating Effect of Aspiration Level

How equity incentives affect corporate performance has become a consensus. However, the question of how to maximize the sustainable incentive effect of equity incentives on corporate performance and avoid “short-sighted” behavior under equity incentives has not yet been resolved. This research re-examines the sustainable incentive of equity incentives and examines the moderating role of aspiration levels based on the behavioral theory of the firm and the prospect theory. Applying panel data comprised 9588 observations from Chinese A-share listed companies spanning the period from 2011 to 2019, this study found that there is an inverted U-shaped relationship between equity incentives and corporate performance. Aspiration surplus negatively moderates the curvilinear inverted U-shaped relationship. As the level of aspiration surplus changes from low to high, the curvilinear relationship between equity incentives and corporate performance is weakened. Aspiration loss positively moderates the curvilinear inverted U-shaped relationship. As the level of aspiration loss changes from low to high, the curvilinear relationship between equity incentives and corporate performance is enhanced. This study demonstrates the importance of aspiration level between equity incentives and corporate performance, guiding firms to focus on the implementation scenario as an influencing factor in order to improve the sustainable incentive effect of equity incentives

Optimization of Deposition Parameters for MPCVD Diamond Coatings Grown on WC-Co Substrates Using Taguchi and Analytic Hierarchy Process Method

In this study, substrate temperature (t), total pressure (p), methane flow (M) and carbon dioxide flow (C) were considered to deposite diamond coatings on WC/Co (6wt.%) substrates under CH4/H2/CO2 atmosphere. The Taguchi method and AHP method were used to determine the parameter plan and the sequence of the parameter plan, respectively. The results showed that three schemes with better parameters could be determined through the Taguchi method, the best parameters with t=750 ℃, p=6 kPa, M=7 mL/min, C=4 mL/min could be choosed based on AHP analysis and the best parameters could be verified through experiment.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author