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The techniques of Active Space Experiments (ASE) include the particles injection and electromagnetic beams emission into geospace from ground or space. Based on the mechanism of the interaction between dusty particles and plasmas in ionosphere, this paper analyses the effect of particle shape on the charge effects of plasma. The processes of superfine particles injection and particle clouds formation are also discussed. This paper presents some results from theoretical analysis, experimental results and numerical simulations. The results show that the well-organized local space structure of nanoscale slender particles cloud display scattering effect to electromagnetic waves along with stronger electron adsorption capacity. The results also show that the nanoscale particles behave the shorter relaxation time than the microscale particles and in mesosphere a particles cloud of 800 meter scale can be produced using the injections method.

APPJs are typically composed of bullet-like plasma volumes travelling with velocities of $10 ^{4-6}\mathrm {m} /\mathrm {s}$, which is close to the propagation velocity of traditional streamers. However, in contrast to the traditional streamers, which propagate in a stochastic manner, plasma bullets have been found to exhibit high repeatability, i.e., propagating the same distance after the same delay time. To understand the high repeatability of the plasma bullets, lots of work has been carried out recently. According to all the studies reported, it is believed that the repeatability of the plasma bullets might be related to background ionization level which is reflected by the density of seed electrons $( n_{seed})$in the gas channel. However, it is not known how high the seed electrons $n_{seed}$is needed for the plasma bullets to propagate in repeatable mode. Besides, when the plasma bullets exhibit random behavior, there are two potential reasons that could result in the unrepeatability, one is the randomness of the ignition and another one is the inconsistence of the propagation speed. This is not clear either.

A 2-D Hybrid numerical model was set up to simulate the process of interaction between large-volume electron-beam-generated plasmas and air flow. High energy electrons were simulated by Monte Carlo numerical method. Low-energy electrons and the ions species excited by collisions were considered by fluid model and simulated by finite-element method. It shows that the air flow can affects the space distribution of low-energy electron density by the convection and transport of ions species. And the influence of the electron beam to the air flow field is only existed in small-scale phenomenon. The velocity field of the far-field air flow is disturbed below 1%. But the electron beam have important effects on the property of boundary layers and the turbulent intensity of the fluid field.

Atmospheric-pressure non-equilibrium plasma jets have recently received a major attention due to their widespread applications in surface and materials processing, biomedical engineering, and medicine. The discovery of fast-propagating plasma bullets opens an ex citing possibility to control sm all bits of plasma sover sub-microsecond and possibly even nanosecond t ime scales. However, this fascinating phenomenon is still challenging to control and is far from being understood despite of a few mechanisms proposed.

Atmospheric pressure non-equilibrium plasma jets (APNP-Js) generate plasmas in open space rather than in confined discharge gaps and are promising for applications in materials processing, nanotechnology, and plasma medicine. High-speed photographs have shown that the plasma plumes are in fact composed of bullet-like plasma volumes travelling at speeds of 104-105 m/s. It is now generally agreed that the plasma bullets are similar to cathode-directed streamers1. For the propagation of cathode-directed streamers, free electrons ahead of the streamer front are needed; Photo-ionization is one of the key mechanisms to produce these free electrons. The existing theoretical models suggest possible critical roles of the local electric field induced by space charges, as well as photo-ionization and residual electron effects. However, we are not aware of experimental reports on the effect of photo-ionization on the plasma bullet propagation.

Room temperature atmospheric pressure plasma jets (RTAPP-Js) have widespread biomedical and health care applications in pathogen inactivation, wound healing, blood coagulation, and interventional oncology, to mention just a few. The overwhelming majority of the existing RTAPP-Js rely on external power (e.g., generators or wall power) and gas feed (e.g., He or Ar gas) supply. This limits their utility in mobile handheld devices for point-of-care applications, e.g., in natural disaster rescue and military combat operations, treatments in remote locations, etc. Moreover, treatment efficacy of such devices should be comparable or superior to current equipment. Recently, Pei et al. have developed a handheld RTAPP-Js (named “Plasma Flashlight”) powered by a 12 V DC battery1. The plasma source does not rely on any external power or feedstock gas supplies. In this report, we quantitative measured the O3 density of the Plasma Flashlight by absorption spectroscopy which was performed with a standard mercury lamp. Atom O and OH radicals that play a crucial role in the inactivation process were measured using the laser-induced fluorescence (LIF) technology. The distribution of Atom O and OH radicals in the plasma plum was also studied.

In recent years, with the popularization of higher education development and the scale of in school students is expanding, Currently in the international it is a general trend of implementing the hierarchical teaching in high school. Based on mission and the current status of the university education, with professional basis requirements of subject settings, this paper discusses practical ideas that the part of professional implements the hierarchical teaching model and disciplines building ideas of classification of teaching management. Through research summarized thus bringing the direction of change in educational administration, meanwhile, the implementation of specific policies for hierarchical teaching the corresponding hierarchical management solutions and suggestions in improving the quality of teaching to enhance students' enthusiasm and creativity, promote development of individual students has a positive reference.

Using the achievements of design based research (DBR) for reference, a novel practical teaching model is presented considering the characteristics of ordinary college students. It creates contest, research and application types teaching environments to keep the stimulation on studying interest. For emphasizing actual teaching and learning effects, multi-level iteration cycles featured by testing are designed to drive teaching process. The model is applied successfully in algorithm course. Specially, the contest-type teaching environment combined with ACM/ICPC has significant effect on improving students' ability of solving problem.