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Objective: Through video analysis, TGMD-3 and BTS three-dimensional infrared motion capture test, explore the development characteristics of 3~6 years old children's throwing action' scientifically guide children's throwing activities, and promote the development of children's movements. Methods: The independent sample T test was used to compare the differences between boys and girls; the one-way ANOVA was used to compare the differences among different age groups; the two-way analysis of variance was used to compare the differences between different ages and stages. Results: (1) The scores of children at different ages and stages were very significant (P<0.001), and the difference between boy and girl Was not significant (P>0.05), and the boys was slightly higher than girls. (3)3~6 years old children showed significant phase main effect (P<0.05) in shoulder flexion, shoulder internal rotation, elbow flexion, wrist flexion, pelvic tilt, upper body rotation, and pelvic rotation. There was not significant at the age effect. Conclusion: (1) The 3-6 year old children's throwing action did not increase linearly with age, and age was not the only benchmark. (2) The 3-year-old group is mainly distributed in the first two stages, and should focus on guiding the arms backwards and legs to move forward; The 4-year-old group is mainly distributed in the first three stages, and The focus of the guiding its footsteps and layering turning; the 5-year-old group is mainly distributed in the second, third an(i fourth stages, and should focus on guiding its stratified body and systemic coordination. (3) The second stage is the bottleneck in the development of preschool children's throwing action, and it is necessary to guide its breakthrough. (4) The characteristics of the 3~6-year-old children's throwing action were: The first stage relies on the elbow and the wrist to brake. The second stage leans forward on the upper. The third stage leans forward and tilts. Force; The fourth stage relies on the force generated by the body forward. The fifth stage is the systemic coordination. The common feature is that the elbow joints are not completely extended. [ABSTRACT FROM AUTHOR]

(NH4)2RuCl6is an important precursor in the synthesis of Ru powder with high-purity requirement. In this study, high-purity (>99.999 wt%) micro-sized (NH4)2RuCl6pieces were synthesized by distillation and precipitation from crude Ru powder. Then, the thermal decomposition behavior of the (NH4)2RuCl6pieces was investigated. The decomposition process included two stages. First, (NH4)2RuCl6was decomposed from 255.0°C to 314.0°C, with the endothermic peak located at 309.4°C. At this stage, HCl and NH3were released, while the dense micro-pieces were transformed to loosened micro-pieces due to the thermal decomposition. Then, the solid phase [(NH3)4Ru3Cl12] kept decomposing from 314.0°C to 352.7°C, HCl and N2were released, and agglomerated Ru particles were achieved. Thermogravimetric analysis-differential thermal analysis-mass spectrum coupling (TG-DTA-MS) was used to monitor the thermal decomposition process and identify the released gaseous phases, respectively. The solid phases in different stages were characterized by high-temperature X-ray diffraction (HTXRD). A good understanding of the processing and thermal decomposition of (NH4)2RuCl6is crucial in the creation of Ru products.

Pt-based high-entropy-alloy nanoparticles (HEA-NPs) have excellent physical and chemical properties due to the diversity of composition, complexity of surface structure, high mixing entropy, and properties of nanoscale, and they are used in a wide range of catalytic applications such as catalytic ammoxidation, the electrolysis of water to produce hydrogen, CO2/CO reduction, and ethanol/methanol oxidation reaction. However, offering a facile, low-cost, and large-scale method for preparing Pt-based HEA-NPs still faces great challenges. In this study, we employed a spray drying technique combined with thermal decomposition reduction (SD-TDR) method to synthesize a single-phase solid solution from binary nanoparticles to denary Pt-based HEA-NPs containing 10 dissimilar elements loaded on carbon supports in an H2atmosphere with a moderate heating rate (3 °C/min), thermal decomposition temperature (300–850 °C), duration time (30 min), and low cooling rate (5–10 °C/min). The Pt autocatalytic behavior was found and investigated, confirming that Pt element could decrease the reduction temperature of other metals via autocatalytic behavior. Therefore, using the feature of Pt autocatalytic behavior, we have achieved Pt-based HEA-NPs at a minimum temperature of 300 °C. We not only prepared a series of Pt-based HEA-NPs with targetable ingredient, size, and phase using the SD-TDR method but also proved the expandability of the SD-TDR technique by synthesizing Pt-based HEA-NPs loaded on different supports. Moreover, we investigated methanol oxidation reaction (MOR) on as-synthesized senary PtCoCuRuFeNi HEA-NPs, which presented superior electrocatalytic performance over commercial Pt/C catalyst.