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Although high-nickel cathode materials LiNi1−x−yCoxMnyO2 (1 − x − y ≥ 0.6, NCM) have high energy density and low cost, they undergo multiple phase transitions during the charge and discharge processes, leading to material cracks and particle pulverization, thereby detaching from the aluminum foil current collector. Herein, a flexible conductive polymer poly(3,4-ethoxythioene) (PEDOT) is electrodeposited onto the LiNi0.8Co0.1Mn0.1O2 cathode electrode. PEDOT is uniformly coated on the cathode material and aluminum foil, acting as a binder it improves adhesion. It also minimizes side reactions between the cathode material and the electrolyte, boosting charge transfer on the electrode surface. Consequently, the interface impedance and charge transfer impedance of the modified electrode decreased from 35.76 and 35.91 Ω to 17.11 and 19.58 Ω, respectively. After 100 cycles at 1C rate within the voltage range of 2.8–4.3 V, the discharge specific capacity of the PEDOT-coated electrode decreases from 177.8 mA h g−1 to 155.2 mA h g−1 with a capacity retention rate of 87.28%, which is significantly higher than 72.74% of the original electrode. [ABSTRACT FROM AUTHOR]

SA516 Gr.70 steels were welded by friction stir welding (FSW) under various media of air, water, and water + CO2 cooling, and the effect of the cooling media on the microstructure and mechanical properties of joints was systematically analyzed. The nugget zone (NZ) under the air-cooling condition contained coarse bainite + martensite. Martensite was obtained by decreasing the cooling media temperature. Furthermore, tensile fracturing of the joints occurred in the basal metal (BM), and the ultimate tensile strength of the joints under various cooling media was similar to that of the BM. However, with decreasing cooling media temperature, the total elongation of the joints noticeably increased. Good strength (545 MPa) and elongation (16.8%) were obtained in the joints under the water + CO2 cooling condition since the fine martensite microstructure enhanced the plastic deformation capacity of the joints. In addition, in the NZ under water + CO2 cooling condition, good toughness of 110 J/cm2 was obtained due to a high fraction of high-angle boundaries and fine martensite. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the characteristics of the combined application of organic fertilizer and inorganic fertilizer using different tillage methods to delay the senescence of maize leaves. The yield and activities of GDH, CAT, APX, GR, and GSH enzymes in maize leaves were measured at different growth stages by using two tillage methods, three organic and inorganic combined applications (P1, P2, and P3), and four control treatments. (1) During the growth period, the R + S and R treatments were P1 treatments, with the highest enzyme activities noted for GDH, CAT, APX, GR, and GSH, which were 36.79–103.22% higher than those of CK. (2) The average yield of all R + S treatments was higher than that of R treatments, and the average yield of P1 treatment was the highest under R + S, which was 13,663.79 kg hm−2, which was 6.39%, 7.90%, and 14.67% higher than that of P2, P3, and CK, respectively, which was lower than that of R. The yield of P1 treatment was 2.53% higher. (3) There was a significant positive correlation between APX activity, CAT activity, GR activity, GDH activity, GSH activity, grain number per ear, ear length, and 100-grain weight of maize leaves at the grain filling stage, and a significant negative correlation between bald tip length and yield. The treatment details had the strongest enzyme activity and the highest yield when using the rotary tillage + subsoiling (R + S) P1 method, which was the most suitable tillage method and the best fertilizer ratio combination, which could be demonstrated and popularized in a large area in the dry farming area of spring maize in Shanxi Province. [ABSTRACT FROM AUTHOR]

The SA516 Gr.70 steel possessing excellent toughness and plasticity has been widely used in the cryogenic field. However, the appearance of coarse bainite in the heat affected zone (HAZ) of the fusion welded joint deteriorates the toughness and ductility. In this work, 4.5 mm thick SA516 Gr.70 steel was joined using shielded metal arc welding (SMAW) and friction stir welding (FSW), respectively, and the microstructure and mechanical properties of joints were investigated in detail. The Charpy energy in the HAZ in the FSW joint was 80 J/cm2, which was higher than that of the HAZ in the SMAW joint (60 J/cm2) and due to microstructure refinement. In addition, the total elongation (TE) of the SMAW joint was 17.5%, which was higher than that of the FSW joint (12.1%) and caused by a wider nugget zone with high hardness. The post-welding annealing was used to improve the toughness and ductility of the SMAW and FSW joints, and the microstructure and mechanical properties of the joints after annealing were analyzed. The toughness in the HAZ of the SMAW and FSW joints were 80 and 103 J/cm2, and the TE of the SMAW and FSW joints were 18.6% and 25.2%, respectively. Finally, the as-annealed FSW joints exhibited excellent toughness and ductility. The abovementioned excellent mechanical properties were primarily attributed to the appearance of tempering martensite, decrease in dislocation density, and fine grain. [ABSTRACT FROM AUTHOR]

Many electric vehicles connected to the grid will lead to problems such as poor stability of power grid generation. The key to solving these problems is to propose an efficient, stable, and economical valley-filling charging scheme for electric vehicles and grid users in the vehicle network system. Firstly, the convex optimization theory is used to make the grid achieve the optimization effect of valley filling. On this basis, the electricity price scheme with a time-varying coefficient as the variable is proposed to meet the single objective optimization of EV charging cost optimization, and its degree of influence on the grid valley-filling effect is analyzed. Secondly, based on the competitive relationship between EV charging cost and battery life, the P2D model is simplified and analyzed, and the attenuation law of battery capacity is quantitatively described. The multi-objective optimization problem is established to express in a Pareto matrix. Finally, the compatibility between the multi-objective optimization and grid valley charging is analyzed. The simulation results show that: (1) The convexity electricity price scheme can satisfy the requirements of various retention rates to achieve the valley-filling effect; (2) The filling effect is satisfied with the electricity price scheme that minimizes the charging cost, and the key factors affecting the filling effect are analyzed; (3) The multi-objective optimization scheme with charging cost and battery life is compatible with the valley-filling effect. [ABSTRACT FROM AUTHOR]

Compliant constant-force mechanisms (CCFMs) are compliant mechanisms that provide nearly constant forces over prescribed deflection ranges. This study proposes a topology optimization method for designing hinge-free compliant constant-output-force mechanisms. Bifurcation cause the objective function to oscillate, leading to convergence failure. Therefore, a constraint for preventing bifurcation in constant-output-force mechanisms is proposed. Moreover, a minimum scale constraint method that extends the design domain is utilized in the proposed optimization algorithm. The relationship between the minimum length scale and the force variation in the optimized CCFM is obtained and discussed, and an optimized CCFM is fabricated and tested. The optimized CCFM exhibits a force variation of 0.7% over a constant-force stroke of 26% of the CCFM length and is thus competitive among recently proposed CCFMs. [ABSTRACT FROM AUTHOR]