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The 12C+12C fusion reaction was studied in the range of E c.m.=8.9 to 21 MeV using the active-target Time Projection Chamber. With full information on all tracks of the reaction products, cross sections of the 12C(12C,8Be)16Og.s. channel and the 12C(12C,3α)12C channel could be measured down to the level of a few milibarns. The 12C(12C,8Be)16Og.s. reaction channel was determined to be 10 mb at E c.m.=11.1 MeV, supporting the direct α transfer reaction mechanism. The 12C(12C,3α)12C reaction channel was studied for the first time using an exclusive measurement. Our result does not confirm the anomaly behavior reported in the previous inclusive measurement by Kolata et al. [Phys. Rev. C 21, 579 (1980)]. Our comparisons with statistical model calculations suggest that the 3α channel is dominated by the fusion evaporation process at E c.m. > 19 MeV. The additional contribution of the 3α channel increases the fusion reaction cross section by 10% at energies above 20 MeV. We also find that an additional reaction mechanism is needed to explain the measured cross section at E c.m. < 15 MeV at which point the statistical model prediction vanishes.

The microstructure and properties of high nitrogen stainless steel welded joints under different flash currents were studied by flash butt welding. The results show that, the flash welding parameters have obvious influence on the joint structure and mechanical properties. The joint is organized into symmetrical distribution, and the grains obtained in the interface area are small, mostly pearlite and ferrite. With the increase of flash current, grain coarsening in overheated zone (OZ) and welding zone (WZ) of joint, which was mainly attributed to the increase of welding heat input. Martensite exists on both sides of the weld, in which the hardness reaches the peak. The tensile strength of welded parts can reach up to 97% of the base material, and the fracture is in the form of ductile fracture.

By the analytical method of system engineering, the air-to-ground precise strike system is set up. Using DoDAF (Department of Defense Architectural Framework, DoDAF), the concept of air-to-ground precision strike is built. The organization is definite and the capability requirement is analyzed. On the basis, the intelligent applications of command and control system, aircraft platform and guided munition are summarized. At last, some suggestion is put forward for the intelligent development of air-to-ground precision strike system.

In this study, the development of air ammunition was reviewed and the new technologies in weapons were summarized, the applications of distribution and synergy technology are proposed in air ammunition. Two representative types of operation were developed to use in battlefield, and the influences of weapons development in the future was analyzed.

The development of the aviation ammunition system has evolved from equipment-based capacity-based. The mapping relations of aviation ammunition mission-ability-weaponry and the capacity-need of different mission are analyzed in this paper. Foreign ammunition development trends and capacity-supported are discussed. Based on the advantages and disadvantages of foreign weapon system architecture, the DODAF (Department of Defense Architecture Framework) and Agent-based system construction strategy is used in the modeling process. This method can provide a certain reference for aviation ammunition architecture.

The Ion Source Group at IMP has been undertaking a series of high intensity ion beam R&D projects. The first project is the development of the intense proton source and its low energy beam transport system (LEBT) for China Initiative Accelerator Driven Sub-Critical reactor (CiADS). The specific characteristics of the proton source are long-term reliability and flexible beam manipulation for the commissioning need of the Superconducting radio-frequency (SRF) accelerators. The LEBT is used to deliver 35 keV H+ beam to the entrance of a 2.1 MeV RFQ . And then the 2.1 MeV proton beam is further accelerated by the superconducting cavities to 25 MeV and eventually goes into a high power beam dumper. Another project is the development of the intense ion source for Jinping Underground Nuclear Astrophysics experiments (JUNA). The ion source was expected to provide 10 emA H+, 10 emA He+ or 2.5 emA He2+ beams for the study of (p, γ), (p, α), (α, p) and (α, γ) reactions in the first phase of the JUNA project. The main challenges of the ion source for JUNA project are production of intense He2+ beam, control of the beam contaminations and beam commissioning a wide beam energy range (70~800 keV) . In this paper, the studies of these intense beam injector systems, for instance, beam intensities, species and ratio, beam transmission efficiency in the LEBT and also the beam optics matching to the downstream accelerator systems will be presented.

Large scale wind turbines lead to increasing blade lengths and weights, which presents new challenges for blade design. This paper selects NREL S809 airfoil, uses the parameterized technology to realize the flexible trailing edge deformation, researches the static aerodynamic characteristics of wind turbine blade airfoil with flexible deformation, and the dynamic aerodynamic characteristics in the process of continuous deformation, analyses the influence of hinge point position on flexible flap aerodynamic performance, in order to further realize the flexible wind turbine blade design and provides some references for the active control scheme. The results show that compared with the original airfoil, proper trailing edge deformation can improve the lift coefficient, reduce the drag coefficient, and thereby more efficiently realize flow field active control. With hinge point moving forward, total aerodynamic performance of flexible flap improves. Positive swing angle can push the transition point backward, thus postpones the occurrence of the transition phenomenon.