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In view of the shortcomings of existing satellite navigation systems in deep-space performance, candidate architectures which utilise libration point orbits in the Earth-Moon system are proposed to create an autonomous satellite navigation system for lunar missions. Three candidate constellations are systematically studied in order to achieve continuous global coverage for lunar orbits: the Earth-Moon L 1,2 two-satellite constellation, the EarthMoon L 2,4,5 three-satellite constellation and the Earth-Moon L 1,2,4,5 four-satellite constellation. After a thorough search for possible configurations, the latter two constellations are found to be the simplest feasible architectures for lunar navigation. Finally, an autonomous orbit determination simulation is performed to verify the autonomy of the system and two optimal configurations are obtained in a comprehensive consideration of coverage and autonomous orbit determination performance. K E Y WO R D S 1. Libration point orbits.2. Satellite navigation. 3. Constellation coverage. 4. Autonomous orbit determination.

The ability of intelligent unmanned platforms to achieve autonomous navigation and positioning in a large-scale environment has become increasingly demanding, in which LIDAR-based Simultaneous Localization and Mapping (SLAM) is the mainstream of research schemes. However, the LIDAR-based SLAM system will degenerate and affect the localization and mapping effects in extreme environments with high dynamics or sparse features. In recent years, a large number of LIDAR-based multi-sensor fusion SLAM works have emerged in order to obtain a more stable and robust system. In this work, the development process of LIDAR-based multi-sensor fusion SLAM and the latest research work are highlighted. After summarizing the basic idea of SLAM and the necessity of multi-sensor fusion, this paper introduces the basic principles and recent work of multi-sensor fusion in detail from four aspects based on the types of fused sensors and data coupling methods. Meanwhile, we review some SLAM datasets and compare the performance of five open-source algorithms using the UrbanNav dataset. Finally, the development trend and popular research directions of SLAM based on 3D LIDAR multi-sensor fusion are discussed and summarized.

In situ growth of ZnO nanorod arrays on cotton cloth (ZnO/CC) was proposed to remove uranium (VI) from aqueous solution. The as-prepared adsorbent is easy separation from the reaction medium after adsorption. The effect factors for uranium adsorption, such as solution pH, initial U (VI) concentration, contact time, and temperature have been systematically investigated. The maximum adsorption capacity of uranium (VI) which was calculated by the Langmuir model at pH=5.0 and T=298 K is 431.03 mg g -1 , exhibiting its excellent uranium adsorption properties. It was observed that the kinetic data fit well to the pseudo-second-order kinetic model indicating that the rate-limiting step of adsorption process is chemical adsorption. Moreover, thermodynamic parameters [ΔH 0 =20.26 kJ mol -1 ΔG 0 =-5.66 kJ mol -1 (298 K) ΔS 0 =86.98 J mol -1 K -1 ] reveal that the uranium adsorption is endothermic and spontaneous. Therefore, the ZnO/CC is a potential adsorbent for recovery of uranium (VI) from aqueous solution.

There are several kinds of Chinese herbal medicines originating from diverse sources. However, the rapid taxonomic identification of large quantities of Chinese herbal medicines is difficult using traditional methods, and the process of identification itself is prone to error. Therefore, the traditional methods of Chinese herbal medicine identification must meet higher standards of accuracy. With the rapid development of bioinformatics, methods relying on bioinformatics strategies offer advantages with respect to the speed and accuracy of the identification of Chinese herbal medicine ingredients. This article reviews the applicability and limitations of biochip and DNA barcoding technology in the identification of Chinese herbal medicines. Furthermore, the future development of the two technologies of interest is discussed.

We consider a highly unconventional superconducting state with chiral d-wave symmetry in doped graphene under strain with the Gutzwiller–RVB method in the momentum space. It is shown that flat bands emerge in the normal state for reasonable strain. As a result, the superconducting critical temperature is found to be linearly proportional to the strength of the electron–electron interaction. Furthermore, the chiral d-wave superconducting state is shown with coexistence of the charge density wave and the pair density wave. There are different coexisting states with those orders under different doping levels.

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