For self-catalyzed nanowires (NWs), reports on how the catalytic droplet initiates successful NW growth are still lacking, making it difficult to control the yield and often accompanying a high density of clusters. Here, we have performed a systematic study on this issue, which reveals that the effective V/III ratio at the initial growth stage is a critical factor that governs the NW growth yield. To initiate NW growth, the ratio should be high enough to allow the nucleation to extend to the entire contact area between the droplet and substrate, which can elevate the droplet off of the substrate, but it should not be too high in order to keep the droplet. This study also reveals that the cluster growth between NWs is also initiated from large droplets. This study provides a new angle from the growth condition to explain the cluster formation mechanism, which can guide high-yield NW growth.

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Stock prediction is a vital and difficult topic where researchers have explored plentifully. Because of some characteristics of the stock market, like high noise and strong nonlinearity, it is quite hard to forecast the price of stock accurately. Long Short-Term Memory neural network (LSTM) uses input gate, output gate and forgetting gate to control information, and shows excellent performance in processing temporal information.

The liquefied petroleum gas (LPG) cylinder incineration test is an important part of the cylinder periodic inspection to clean up the residual gas and ensure the safety of subsequent inspection items. However, the cylinder needs to be incinerated several times due to the uneven temperature distribution of the cylinder, leading to low incineration efficiency and waste of energy. In this study, a cylinder incineration test is experimentally investigated and a computational fluid dynamics (CFD) model is established to analyze the influence of incinerator structure parameters and cylinder types on the temperature uniformity of the cylinder. The results show that the temperature distribution of the middle surface of the cylinder is most uneven. With the increase of the burner nozzle diameter and the incinerator diameter, the standard deviation of temperature decreases at first and then increases, and the minimum is reached at 150 mm and 530 mm, respectively. The optimized design is found to have a better temperature uniformity of the cylinder with the burner nozzle angle of 0?. The optimal incinerator diameter for different types of LPG cylinders is different and decreases as the cylinder diameter decreases.