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The greatest challenge of electrostatic levitation for containerless material processing is the stable control of charged material during heating. Recently, high-precision self-adaptive control of electrostatic levitation has been achieved in China's Space Station. Based on the 1D and 3D co-simulation analysis, an optimal scheduling of control strategies of sample release and retrieval in space is developed. Both simulation results and on-orbit experiments demonstrated that the inversion of surface charge is responsible for the heating induced material instability. On-orbit experiments indicated that under laser illuminations, the net surface charge of metal Zr changed from positive to negative at 900 K and from negative to positive at 1300 K. The possible physical mechanism of the charge inversion of heated material is discussed. [ABSTRACT FROM AUTHOR]

With the construction and future operation of the China Space Station (CSS), requirements of extensive preliminary ground experiments for projects onboard CSS, as well as those of scientific experiments utilizing ground-based short-term microgravity facilities, are increasing rapidly. A new microgravity experiment facility with electromagnetic launch is proposed and built by the Technology and Engineering Center for Space Utilization of Chinese Academy of Sciences. The design details of electromagnetic microgravity facility are introduced in this paper. This facility is mainly composed of double layered tower, linear induction motors, experimental capsule, energy storing device, high-power converters, electrical control system and electromagnetic release device. Then the microgravity level of the experimental payload achieved is evaluated through the analysis of kinematics and dynamics. The results of analysis indicate that the microgravity level of 10–5 g can be achieved for 4 s and optional gravity level from 10–5 g to 1 g can be created. With the drive concept, this facility will be capable of performing that the interval time between two experiments is less than 10 min. The acceleration and deceleration of experimental capsule can be controlled within 5 g through electromagnetic accelerating and electromagnetic braking. Physical verification and simulation tests are carried out on key technologies such as principle of electromagnetic launch, linear motor control, and electromagnetic release, which prove the effectiveness of the technical feasibility. [ABSTRACT FROM AUTHOR]

The V R I passbands light curves of V344 Lac were presented and analyzed by using the latest version of the W-D code. The observed spectrum reveals that V344 Lac is not an A3 type but would be a later F type star according to the yielded temperature. The results of solution show that V344 Lac is an A-subtype contact binary, with a moderate photometric mass ratio of 0.387 ± 0.003 and a moderate contact factor of 44.6 ± 3.0 % . Based on the parallax given by Gaia, the parameters of the components are estimated as: M 1 = 1.16 M ⊙ , M 2 = 0.45 M ⊙ , R 1 = 1.31 R ⊙ , R 2 = 0.88 R ⊙ , L 1 = 2.512 L ⊙ , L 2 = 1.057 L ⊙ . The period investigation indicates that V344 Lac may have an eccentric orbital oscillation, with P 3 = 12.4 ± 0.5 yr , A 3 = 0.0020 ± 0.0002 d , and e = 0.38 ± 0.16 . Analysis shows such oscillation would be caused by a magnetic activity which can be explained by the Applegate mechanism. Meanwhile, according to the value of l 3 and the estimated physical parameters of V344 Lac, the mass of the third companion may be 0.79 M ⊙ . This third body could be a wide company. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) sea-urchin-like hierarchical TiO microspheres were synthesized by a template-free hydrothermal method. The effects of preparation parameters on the microstructure of 3D sea-urchin-like hierarchical TiO were investigated using scanning electron microscopy (SEM), transmission electron microscopy, X-ray diffractometer, energy-dispersive X-ray spectrometer and Brunauer-Emmett-Teller technologies. The growth mechanism and photocatalytic activity of 3D sea-urchin-like TiO microspheres were discussed. The results of electron microscopy characterizations SEM showed that the microspheres were consisted of numerous one-dimensional (1D) nanorods. A three-step growth model: oxygenated to be 1D nanorods, self-assembly and protonation, was proposed to illustrate the growth mechanism of sea-urchin-like structures. The synthesized 3D sea-urchin-like hierarchical TiO microspheres exhibited a better photocatalytic activity for photodegradation of rhodamine B under sunlight irradiation compared to that of P25, which was attributed to the special 3D hierarchical nanostructure, the increased number of surface active sites and anatase crystal structure. [ABSTRACT FROM AUTHOR]