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In this paper, we investigate the impact of driving current and environmental conditions on a commercially available 0.13‐inch InGaN‐based green‐colored Micro‐LED display with a resolution of 640 x 480 pixels. Through comprehensive testing, we aim to provide insights into the performance characteristics of Micro‐LEDs under various operational scenarios. [ABSTRACT FROM AUTHOR]

The purpose of this work was to investigate the thermodynamic characteristics of carbon dioxide (CO2) adsorption on a promising nitrogen‐doped biochar at constant temperature and isopiestic pressure. The biochar was prepared as a CO2 adsorbent based on catalytic pyrolysis of pristine coconut shells using urea as the nitrogen source and moderate temperature ionic liquid as a catalyst. The results showed that CO2 adsorption on the biochar was a spontaneous, dominantly physical, exothermic, and entropy decrement process that could be well described by the slip model and the dual‐site Langmuir model. Those thermodynamic parameters, including interface potential, exhibited a series of interesting tendencies with the changes in adsorption temperature and pressure. Under the conditions of 273 K and 100 kPa, the adsorption capacity and the interface potential were 4.6 mmol/g and −16.7 J/g, respectively. And the site energy ranged from 2.57 to 5.13 kJ/mol in the test conditions, which became narrow with increasing temperature. The temperature exhibited positive effects on interface potential, enthalpy change, entropy change, enthalpy change, internal energy change but negative effects on adsorption capacity, Gibbs free energy change, and Helmholtz free energy change. Interestingly, the pressure exhibited the opposite effect trends. The peak pressure with maximum temperature effect at a given temperature and the peak temperature with maximum pressure effect at a given pressure were found to exist for some thermodynamic parameters. These exhibited a different but significantly beneficial perspective to understand the mass and energy transfer during CO2 adsorption on the biochar at constant temperature and isopiestic pressure, which have rarely been reported before. [ABSTRACT FROM AUTHOR]

Serial robots have been successful in numerous applications; however, their limited motion accuracy hinders the potential for high precision robotic machining. Among the many sources of error in robot movement, non-linearities at robot joints, namely backlash and stiction/friction, are yet to be thoroughly investigated and addressed. When a robot joint reverses, backlash-induced excitation switches direction and stiction induces localized errors that occur over a short duration. Together, backlash and stiction from joint reversal lead to significant positional errors. This paper closes the research gap by proposing feedforward backlash and stiction compensation with a focus on suppressing errors during joint reversals. The controllers are designed using experimental studies of robot joints and the nominal tool centre point (TCP) trajectories. Based on the robot kinematics, the strategy interpolates the nominal trajectories to ensure accurate identification of joint reversals along the path, and therefore provides optimal error compensation with minimum latency. The performance of the controller is evaluated in single axis tests for suppressing backlash in static conditions and in multi-axis path tests for suppressing backlash and stiction in continuous motions. The experimental results show that the feedforward compensation greatly improves the robot accuracy during joint reversal, reducing errors by more than 70%. [ABSTRACT FROM AUTHOR]

With a purpose of extending the application of β-cyclodextrin (β-CD) for gas adsorption, this paper aims to reveal the pore formation mechanism of a promising adsorbent for CO2 capture which was derived from the structural remodeling of β-CD by thermal activation. The pore structure and performance of the adsorbent were characterized by means of SEM, BET and CO2 adsorption. Then, the thermochemical characteristics during pore formation were systematically investigated by means of TG-DSC, in situ TG-FTIR/FTIR, in situ TG-MS/MS, EDS, XPS and DFT. The results show that the derived adsorbent exhibits an excellent porous structure for CO2 capture accompanied by an adsorption capacity of 4.2 mmol/g at 0 °C and 100 kPa. The porous structure is obtained by the structural remodeling such as dehydration polymerization with the prior locations such as hydroxyl bonded to C6 and ring-opening polymerization with the main locations (C4, C1, C5), accompanied by the release of those small molecules such as H2O, CO2 and C3H4. A large amount of new fine pores is formed at the third and fourth stage of the four-stage activation process. Particularly, more micropores are created at the fourth stage. This revealed that pore formation mechanism is beneficial to structural design of further thermal-treated graft/functionalization polymer derived from β-CD, potentially applicable for gas adsorption such as CO2 capture. [ABSTRACT FROM AUTHOR]

Serial-link industrial robots that feature small footprints and large working volumes have been used widely in various applications. However, their low-stiffness-induced vibration hinders application in precision robotic machining processes. In robotic milling, the spindle may experience chatter, leading to unsatisfactory surface finishes. Moreover, the chatter frequency varies, depending on the robot pose and its underlying stiffness and inertia characteristics, which is likely to be outside of the controlled robot system bandwidth. One solution is to use inertial actuators close to the source of excitation on the robot to generate forces that counteract the vibration. This paper advances matters by employing optimised H∞ control strategies for improved effectiveness and robustness to perform active vibration suppression. The strategies are independent of tool paths and take account of different robot poses, hence the variability of the robot dynamic characteristics. Performance is assessed against that of standard velocity feedback controllers in eccentric mass experiments and milling tests. The experimental results show that within a relatively large work-plane (500 mm × 500 mm), H∞ controllers greatly improve machining capability and reduce machining errors by up to 85%. [ABSTRACT FROM AUTHOR]