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A photoredox/copper cocatalyzed domino cyclization of oxime esters with TMSCN has been developed. A range of structurally novel tetrasubstituted pyrazines have been obtained. This method features high bond-forming efficiency, high step economy, broad substrate scope, and gram-scale synthesis. Moreover, preliminary bioactivity evaluation of pyrazine products shows their promising antifungal activities.

A novel and efficient photoredox/copper cocatalyzed domino cyclization of oxime esters, aldehydes, and amines has been achieved, affording a broad range of fully substituted 1H-imidazoles in good yields.

With the expanding demand to meet specific safety requirements, a new definition of the architecture at the system level is required to keep the powertrain system still operational after the fault emerge of some sensors. This work proposes a fail-operational architecture by integrating battery management and motor control system, which implements heterogeneous sensor signal reconstruction and model-based signal estimation for redundant signal generation and adopts random forest for signal arbitration. The proposed architecture can reduce the system failure rate and allow a fault-toleration of up to three sensors at any given time without increasing costs. Finally, the proposed architecture was verified by comparing the fault detection performance among three arbitration algorithms in a model in the loop (MIL) platform.

A capacitive tactile sensor based on conventional four-planar-capacitor arrangement was advanced in electrode arrangement. The advanced design enhanced the spatial resolution of the tactile sensing unit without sacrificing its sensitivity because the sizes of the four capacitors were not altered. Results indicated that the spatial resolution was enhanced for more than doubled with normal force sensitivity of 3.261 pF/N and the average detection tolerance of the shear angle negligible. This work provided a solution to existing conventionally designs and existing capacitive tactile sensors to enhance the spatial resolution simply by algorithms instead of by any laborious physical modifications.

Even when made by brittle materials, awl-shaped serpentine microsprings (ASSMs) were found to have a nonlinear displacement&ndash, force relationship similar to springs made by ductile material. It is found that the nonlinear displacement&ndash, force relationship is due to the geometry and dimensions of the ASSMs. The geometric effect of the nonlinear force-displacement relationship of ASSMs for in-plane motion was investigated. A theoretical solution was derived to analyze this nonlinearity. By successfully fabricating and measuring an ASSM, the theoretical results agreed well with the experimental results. The results indicated that ASSMs have a nonlinear force-displacement relationship, which is similar to that of hardening springs. The taper angle has a significant effect on the nonlinear displacement of ASSMs. When the taper angle was small, no obvious effect appeared on the nonlinearity of the microsprings with different numbers of turns. When the beam length increased, the critical force for nonlinear deflection decreased.

An asymmetric (4 + 1) annulation of α-nitro cinnamates with Morita-Baylis-Hillman (MBH) acetates catalyzed by α-isocupreine is reported. It provides chiral isoxazoline N-oxides in moderate to good yields with 88-99% ee, and represents the first catalytic asymmetric (4 + 1) annulation of activated nitroalkenes with in situ generated ammonium ylides. It also affords a practical and efficient access to chiral isoxazoline N-oxides.

Tea polysaccharides (TPS) are regarded as some of the main bioactive constituents of tea made from the leaves and buds of the tea plant ( Camellia sinensis L.). An increasing number of studies have demonstrated that TPS can reduce the risk of type 2 diabetes, obesity, and other metabolic diseases. However, the potential mechanisms responsible for antidiabetic and antiobesogenic activities of TPS remain unclear. Therefore, the cellular and physiological mechanisms that underlie the antidiabetic and antiobesogenic effects, including antioxidant and anti-inflammation effects, inhibition of digestive enzymes, prevention of macronutrient absorption, and expression of gene and protein, were summarized in this review. Furthermore, the gastrointestinal functions of TPS and the role of gut microbiota in the prevention and treatment of metabolic diseases were discussed. It is expected that the present review will be helpful for enhancing our knowledge about the health-promoting effects of TPS on metabolic diseases and stimulating further works on TPS.

A metal-free direct aerobic oxyphosphorylation of alkenes with H-phosphine oxides has been developed utilizing visible light photoredox catalysis. A variety of β-ketophosphine oxides have been obtained in good yields from simple olefins under air with inexpensive rhodamine B as the non-metallic photocatalyst. This method provides a mild, green, and practical synthetic approach to valuable β-ketophosphine oxides.

In the development of artificial electronic skin (e-skin), a flexible tactile sensor is a critical component that imitates human skin response to dynamic and static stimuli. In this study, we developed a novel multifunctional tactile sensor to mimic human skin with high force sensitivity, high flexibility, and temperature measurable performance. The unique geometry of the interlocked structures enabled differentiation between different mechanical stimuli, including pressure, bending and torsion forces. The substrate was flexible because of the material properties of the polydimethylsiloxane (PDMS) layer. The top electrode and bottom electrode layers were interlocked by high-aspect-ratio zinc oxide nanorods (NRs), which were grown vertically on the PDMS surface, providing high sensitivity for the measurement of contact force and environmental temperature. Moreover, the sensor was applied for measuring and monitoring arterial pulse pressure. Thus, we successfully fabricated a 3 × 3 sensor array with multiple functions, which were verified through experiments. In the future, the proposed tactile sensor can be used in wearable health care devices, flexible interfaces, and bionic robotic skins in the industry.

An amine-catalyzed reaction between Morita–Baylis–Hillman (MBH) acetates and isatins to provide facile access to structurally interesting 3-hydroxyoxindoles in moderate to good yields with diastereomeric ratios of 1:1 has been developed. A wide variety of isatin derivatives were tolerated under the conditions of this tandem reaction. Notably, the inert homoallylic methyl group of MBH acetate 1 was directly involved in the bond formation step, which was followed by a [4+2] annulation under mild conditions to lead to the desired products.

A series of polysubstituted furans and dihydrofurans have been prepared from readily available oxodienes and bromonitromethane in modest to excellent yields. This facile synthetic method is developed on the basis of proprietary properties of nitro group such as strong electron-withdrawing ability and cleavability. The conversion of nitro-substituted dihydrofurans to furans is presumably realized by elimination of HNO 2 under the aid of DABCO.

In this study, the spatial resolution of a capacitive tactile sensor was enhanced more than fourfold without sacrificing the sensitivity and functionality of the sensor, compared with conventional sensors with a planar capacitance arrangement. Through the vertical stacking of two capacitors with a shared electrode, the spatial resolution was at least doubled in both x- and y-directions, and the overall density of the sensing unit was more than quadrupled for arbitrary application sizes. In addition to shear angle detection, sensing demonstrations were performed on the normal and shear forces with theoretical designs, numerical evaluations, and empirical examinations. The proposed capacitive tactile sensor has a simplified manufacturing process and an efficient detection method realized by the shared electrode, in addition to the enhanced spatial resolution. This novel design can be applied to automatic robots for grasping tiny objects because the spatial resolution can be enhanced by simply replacing the four capacitors in a conventional planar arrangement with two vertically stacked capacitors as a universal solution.

A phosphine-catalyzed [4 + 2] annulation of α-substituted allenoate with exocyclic alkene moiety of oxindoles or indan-1,3-diones has been developed. Thus, under the catalysis of PPh3 (20 mol%), a series of spirooxindole- or spiroindan-1,3-dione-cyclohexenes have been obtained in moderate to excellent yields and regioselectivity from the annulations of α-methyl allenoates with 3-methyleneoxindoles or 2-methyleneindan-1,3-diones. This method offers an easy access to structurally novel spirocyclohexenes.

This paper is aimed to propose a decoupled self-tuning proportional plus integral (PI) controller with simple law for an idling stop system applied to scooters. An integrated starter generator (ISG) of the idling stop system is designed with a high efficiency permanent magnet synchronous motor (PMSM). The PMSM used as an ISG must have a high torque characteristic to ensure that the engine can be accelerated up to firing speed. A conventional and useful control algorithm named PI control is unable to handle motor current very well for dynamic load, parametric variation, and external disturbance, especially in a vehicle application. Therefore, a robust algorithm for current control in an ISG is proposed. The decoupled selftuning PI controller based on the Lyapunov stability theorem is utilized to guarantee the control performance. Numerical simulations demonstrate the effectiveness of the proposed control algorithm. Experimental results show that the engine of a 150 cm3 scooter can be cranked to reach firing speed by a ISG within 0.1−0.2 second. The proposed method is simple, robust, as well as stable for idling stop system, and can be effectively implemented.

An integrated starter generator is widely used in vehicles. In this study, the goal is to maintain an integrated starter generator system working accurately and respond instantaneously during sensors failure. A redundant signal is established by signal reconstruction and estimation method. To switch among multi-signal sources, a signal arbitration is done based on random forest algorithm. The accuracy of fault diagnosis is higher than 99.82%, and 14 kinds of signals failure can be identified.

This study presents a MEMS IR-laser beam scanning system consisted of the micro Fresnel lens and linear comb actuators. The merits of this study is to fabricate and further integrate the binary phase Fresnel lens, micro springs, and micro electrostatic actuators through the silicon micromachining processes to achieve the proposed IR-laser beam scanning system. Thus, the difficulty and problem resulted from assembly can be prevented. The proposed IR-laser beam scanner is a spring-mass system driven by linear comb-drive actuators, and operates at the resonant frequency to enlarge the scanning angle. Measurements indicate the scanner has a resonant frequency of ~2 kHz (exceeds the millisecond minimum response time requirement for application), and a displacement of greater than ±20μm at a driving voltage of V DC =12.5V, V pp =18V. Moreover, the 1550 nm infrared laser beam has a deflection angle of ±6.84°.

A capacitive tactile sensing unit with an asymmetric electrode arrangement to support tolerable angle detection errors (ADEs) in processes and operations was proposed and demonstrated in this study. Each capacitor in the sensing unit contains one fan-shaped electrode on top and one square-shaped electrode at the bottom with an intentional shift on the xy-plane, which alleviated the rotational misalignment and suppressed shear force ADE from more than 2.5° to less than 0.4°. The suppression of the ADE was realized by enlarging the sector angle of the fan-shaped electrode to 100°, which provided 5° clockwise and 5° counterclockwise coverages for electrode alignment. Complete theoretical derivation of the relationships among the capacitors, design, simulation, and measurement was conducted in this research. Experimental results proved that this fan-shaped electrode design showed identical functionalities and sensitivities to those of the square-shaped electrode design for capacitive tactile sensing applications.

This study develops an automated wafer-level testing system, using visual and laser as the sensing devices, which can be the platform of MEMS measurement at wafer level. The proposed system involves the development of human-machine interface and precisely positioning control, which includes camera module for visual identification, motorized micro positioners, laser sensors for probe positioning automated, and wafer movable stage for the wafer positioning.

This work proposes an intelligent bearing fault diagnosis system using Convolutional Neural Network (CNN) in deep learning to achieve the abnormal identification of bearing vibration. In this system, the convolutional kernel in CNN can automatically extract the features of input signals and no human feature extraction and other data pre-processing are required. As a result, comparing to the traditional signal processing methods, this work has the advantages of automated end-to-end, high-accuracy and intelligent machine troubleshooting in vibration fault diagnosis of bearings.

This study presents a novel multifunctional tactile sensor to mimetic the human skin with high sensitive, flexible, and temperature measurable performances. The substrate is flexible due to the material property of the Polydimethylsiloxane (PDMS). The top electrode and bottom electrode layers are interlocked by the zinc oxide (ZnO) nanorods, which is vertically growing on the top of PDMS, providing high sensitivity for the measurement of the contact force and environment temperature. In this work, we successfully fabricated the tactile sensor array with multiple functions mentioned above by the experiments, which is expected to be employed in the artificial electronic skin (e-skin). In the future, the proposed tactile sensor can be utilized in the wearable device, flexible interface, and bionic robot skin in the industry.