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Plasma spray-physical vapor deposition (PS-PVD) enables the modulation of both the microstructure and the performance of the coating by modulating the ratio of the three phases (gas, liquid, and solid) present in the jet. Considering the observed deficiency in the erosion resistance of PS-PVD coatings, the study explores improving high-temperature erosion resistance in PS-PVD thermal barrier coatings by adjusting Ar/He flow ratios. At a plasma gas flow rate of 90 SLPM, increasing the Ar/He ratio enhances nanohardness and elastic modulus. An Ar/He ratio of 2:1 provides erosion resistance comparable to standard APS coatings. Raising the plasma flow to 120 SLPM with the same Ar/He ratio forms a dense coating with low erosion rates. The study identifies a strong correlation between the hardness of the coating and erosion resistance. Lateral cracking from high-temperature and high-speed particle erosion is identified as the primary cause of failure. • Plasma gas flow and Ar/He affect the coating's microstructure and properties. • Coating hardness positively correlates with high-temperature erosion resistance. • Coatings with different structures show distinct erosion failure modes. [ABSTRACT FROM AUTHOR]

In this paper, a common sharing method for current and flux-linkage control is proposed for high performance control of the switched reluctance motor (SRM). The proposed method not only can realize the current and flux-linkage sharing between different phases of the SRM, but also can reduce the torque ripple to a very low level. With the current-sharing method (CSM), the SRM can be controlled without any model information besides the phase number of the SRM. While with the flux-linkage-sharing method (FSM), high control performance can be achieved with inner flux-linkage loop alone. Six control parameters of the common sharing method can make the method possess high adjusting freedom. The CSM and the FSM are applied to speed control of a four-phase 8/6 SRM respectively. The speed controller is composed of the proportional plus derivative (PD) controller and adaptive linear element (Adaline) with sliding mode learning algorithm (SMLA). The comparisons between the control performance of the CSM and the FSM are given. Simulation results certify that the common sharing method can be applied to the current and flux-linkage control of the SRM effectively, and the combined controller can enhance the accuracy and robustness of the speed controller. [ABSTRACT FROM AUTHOR]

Abstract: A layer-by-layer (LBL) approach was used to assemble alternating layers of sodium alginate (ALG)/polyethyleneimine (PEI) on biaxially oriented poly(lactic acid) (BOPLA) films in order to produce bio-based all-polymer thin films with low gas permeability. Increasing the depositing of ALG and PEI from 0 to 30 layers results in large thickness variations (from 0 to 3.92μm). After 30 ALG/PEI layers are deposited, the resulting assembly has an OTR of 1.22cm3/(m2 dayatm). When multiplied by thickness, the resulting oxygen permeability (OP) is found to be less than 3.8×10−17 cm3 cm/cm2 sPa, which is almost 3 orders of magnitude lower than that of uncoated BOPLA film (1.8×10−14 cm3 cm/cm2 sPa). At the same time, the resulting multilayer-coated BOPLA films maintain high optical clarity and tensile properties. This unique barrier thin film has become a promising alternative to non-biodegradable synthetic food packaging materials. [Copyright &y& Elsevier]

Abstract: X–Z inverted pendulum is a new kind of inverted pendulum which can move with the combination of the vertical and horizontal forces. Through a new transformation, the X–Z inverted pendulum is decomposed into three simple models. Based on the simple models, sliding-mode control is applied to stabilization and tracking control of the inverted pendulum. The performance of the sliding mode control is compared with that of the PID control. Simulation results show that the design scheme of sliding-mode control is effective for the stabilization and tracking control of the X–Z inverted pendulum. [Copyright &y& Elsevier]

Abstract: The dissipative particle dynamics (DPD) is used to study the compatibilizing process of an immiscible polymer blend using a graft copolymer as a compatibilizer. Polystyrene (PS) and polyamide 6 (PA6) are chosen as the polymer components of the blend. The graft copolymer is composed of PS as the backbone and PA6 as the grafts. Mesoscale morphology, density distribution, end-to-end distance of PA6 and interfacial tension are investigated. Simulations show that the presence of a graft copolymer contributes to the formation of finer and more uniform dispersed domains by preventing them from collision and coalescence. In the presence of a graft copolymer, the density distribution is more uniform and the dynamic equilibrium of the blend morphology is reached more rapidly. For a given backbone and number of grafts per backbone, the compatibilizing efficiency of the graft copolymer first increases with increasing graft length. However, when the graft length exceeds a certain value, it starts decreasing. [Copyright &y& Elsevier]

Abstract: Micromixing of viscous systems in a stirred-tank reactor with Rushton turbine is investigated numerically. It is characterized by the product selectivity of parallel competitive reactions. Flow fields inside the reactor are determined by the Reynolds Stress Model (RSM). A computational fluid dynamics (CFD) method combining the standard E model and Finite-Rate/Eddy-Dissipation (FR/ED) model is implemented and is validated using experimental data in the literature. The simulations show that a higher agitation speed, a lower fluid viscosity and/or a feeding location closer to the discharge area of the impeller favor micromixing and the reaction rate. The trajectory of the reaction plume also influences the micromixing performance. The value of the FR/ED model parameter determined by lab-scale experiments decreases with increasing fluid viscosity. However, it is little affected by the agitation speed. These results provide useful guidelines for the scale-up of industrial reactors with complex chemical reactions. [Copyright &y& Elsevier]

Abstract: The inverted pendulum problem is one of the most important problems in control theory and has been studied excessively in control literatures. When a control system have more than two PID controllers, the adjustment of PID parameters is not an easy problem. In this paper, PID controllers are applied to the stabilization and tracking control of three types of inverted pendulum. The way how to design the PID controllers is given step by step in this paper. Simulation results prove that the way to design of PID controllers is very simple and effective. The system design not only can realize stabilization and tracking control of three types of inverted pendulum, but also have robustness to outer large and fast disturbances. [ABSTRACT FROM AUTHOR]

The development of high-performance anion exchange membranes (AEMs) has become more urgent for fuel cells. One of the critical challenges is to prepare AEMs with sufficient ion conductivity and robust alkaline endurance. In this work, bulky twisted binaphthyl units are introduced into the backbones of AEMs by a one-pot superacid-catalyzed polymerization to enhance both the conductivity and stability. The binaphthyl unit can depress the chain packing density and enlarge the free volume of the AEMs, conducing to form well-defined microphase separation and to build well-developed ion-conductive highways. The poly(binaphthyl piperidinium)-based AEM (QABNP) shows the highest OH− conductivity of 135.25 mS cm−1 superior to the poly(quaterphenyl piperidinium)-based AEM (QAQPP) (109.12 mS cm−1). Meanwhile, the QABNP AEM exhibits about 90% conductivity retention after being tested in a harsh alkaline environment (2 M NaOH at 80 °C) for 1080 h. Importantly, the QABNP based single cell possesses the highest peak power density (PPD) of 1.16 W cm−2 at a high current density of 2.37 A cm−2 with a low high frequency resistance (HFR) of 0.04 Ω cm2. This study demonstrates the merits of bulky twisted binaphthyl incorporated in a polymer backbone for improving AEM performances. [Display omitted] • The twisted poly(binaphthyl piperidinium) (QABNP) is synthesized. • Well-defined microphase separation morphology in QABNP is constructed. • High conductivity and excellent alkaline stability can be obtained. • The highest power density reaches up to 1.16 W cm−2. [ABSTRACT FROM AUTHOR]

Abstract: In this study, carbon-supported PtNi alloys with different molar ratios synthesized by borohydride reduction were evaluated as anode catalysts for sodium borohydride fuel cells. The higher angle shifts of the Pt peaks from X-ray diffraction (XRD) account for the alloy formation between Pt and Ni. The negative shift of Pt 4f XPS spectrum for PtNi(7:3)/C also indicates an electronic structural change of Pt in the alloyed PtNi/C catalyst. The cyclic voltammetry (CV) results show that the PtNi(x:10− x)/C catalysts are electrochemically active toward borohydride oxidation at the potential range between −0.6V and +0.1V vs. Hg/HgO electrode, and PtNi(7:3)/C presents the strongest peak current density among three catalysts with different molar ratios. The results of amperometric i–t curves (i–t) tests also show that the steady-state current density is the highest on PtNi(7:3)/C among alloy catalysts. The higher electrocatalytic activity of the PtNi(7:3)/C can be attributed to the alloy effect and the Pt electronic structure change due to the addition of Ni. [Copyright &y& Elsevier]