Electrospray deposition(ESD) as a patterning method of nanoparticles deposited on a substrate has attracted much attention due to several advantages over other methods.However,obtaining an optimum ESD processing condition for nanoparticle pattern relies much on trial experiments because of the lack of reliable numerical simulation.In this study,the deposition characteristics of nanoparticle generated by electrospray were investigated by using a three-dimensional Lagrangian model.Three important process parameters,including solution dielectric constant,applied voltage and surface charge density on mask were considered by fixing the geometrical parameters of the ESD device.Simulation result showed that under the condition of without a mask,the spray diameter increases with increasing solvent dielectric constant,and higher applied voltage makes the spray area wider.Controllability of focusing by changing surface charge density on the mask was confirmed:higher surface charge density on the mask results in more focused deposition.Validity of the numerical simulation developed in this study was verified by comparison with experimental data. 相似文献
In gas-insulated equipment, partial over-thermal faults may occur due to poor contact and other reasons. The main insulation medium SF6 may decompose under over-thermal conditions and produce harmful products such as SO2 and HF, which can damage the equipment and reduce the insulation strength of the equipment. The method of decomposition component analysis can monitor the operating status of equipment without interference from machinery, noise and optics, and provide early warning or reminder of faults, but the premise is that the decomposition mechanism of SF6 must have been fully and in-depth understood. In the decomposition process of SF6, O2 has a significant effect, but the mechanism of the effect is still unclear. Based on the isotope tracing method, this paper uses 18O2 instead of ordinary O2 for overheating experiments. Through the quantitative detection of the labeled products in the product and the abundance of 18O isotope in the products, the effect of O2 on the formation of the main decomposition products was analyzed. The work makes the reaction process and mechanism of SF6 with trace oxygen under over-thermal conditions basically clear, which provides an important theoretical basis for on-line monitoring and fault diagnosis of equipment based on chemical analysis methods.
A technology credit guarantee policy has been established to provide financial support to technology-based SMEs with a limited asset base. For an effective technology credit guarantee policy, risk management is essential. In this paper, we investigate a survival model that predicts start-up SMEs’ loan default probability at a given time based on technology attributes along with the economic environment and the firm’s characteristics at the time of the technology credit guarantee fund application. This, in turn, is used for the estimation of the technology fund risk along with a stress test. Our work is expected to contribute to reducing the risks associated with technology financing. 相似文献