The instability of the motion layer of fertilizer particle influences the precision and the accuracy of the amount of fertilizer application in the working process of fluted-roller fertilizer applicator. The characteristics of the motion layer were investigated, and a systematic scheme was proposed for designing the structures of fertilizer-filling cavity, fertilizer-filling surface and fertilizer-delivery cavity. The key parameters of the structure were studied by discrete element method. It was figured out that to ensure the smooth operation of fertilizer applicator, the fertilizer-filling angle was 105°, fertilizer-contact angle should be large than 100°, and the fertilizer-resistance angle should be smaller than 35°. Moreover, the stability of fertilizer motion morphology was investigated to verify the design. The results showed that when the roll rotational speed was larger than 120 deg/s, compared with the conventional design the CV of the amount of fertilizer application was reduced from 1.5%-3.5% to 0.5%-1.0%, and the accuracy of the fertilizer discharge was improved with the square of the correlation coefficient between the amount of fertilizer application and the roll rotational speed was larger than 0.999. It was deduced from the results that the precision and accuracy of the amount of fertilizer application are improved via eliminating the driving layer and enhancing the stable filling and conveying of the forced layer.

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Using natural light energy to convert water into hydrogen is of great significance to solving energy shortages and environmental pollution. Due to the rapid recombination of photogenerated carriers after separation, the efficiency of photocatalytic hydrogen production using photocatalysts is usually very low. Here, efficient CdZnS nanoparticles@Ti3C2Tx MXene nanosheet heterojunction photocatalysts have been successfully prepared by a facile in situ growth strategy. Since the CdZnS nanoparticles uniformly covered the Ti3C2Tx Mxene nanosheets, the agglomeration phenomenon of CdZnS nanoparticles could be effectively inhibited, accompanied by increased Schottky barrier sites and an enhanced migration rate of photogenerated carriers. The utilization efficiency of light energy can be improved by inhibiting the recombination of photogenerated electron-hole pairs. As a result, under the visible-light-driven photocatalytic experiments, this composite achieved a high hydrogen evolution rate of 47.1 mmol h−1 g−1, which is much higher than pristine CdZnS and Mxene. The boosted photocatalytic performances can be attributed to the formed heterojunction of CdZnS nanoparticles and Ti3C2Tx MXene nanosheets, as well as the weakened agglomeration effects.