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China's first Mars exploration mission will carry out comprehensive global surveys of the planet from data collected by instruments carried in orbit and roving on the planet itself. Goals of the mission include detailed inspections and surveys of key areas on the surface of Mars. One of the main scientific payloads installed on the orbiter is the moderate resolution camera. Its mission is to image the surface of Mars sufficiently to produce a global remote sensing image map of the planet, and to explore and record changes to the topography of Mars, including major geological structures, and to advance research on topography and geomorphology in general. The moderate resolution camera uses a lightweight and compact integrated design; its primary components are an optical module, a focal plane module, a camera control module, a power and interface module, a camera support module, a thermal control module, and a reference module. Radiometric calibration, color calibration, and geometric calibration have been carried out to ensure that the camera can acquire sufficient accurate data to complete mission goals. This paper introduces the camera's detection mission, its system composition, and its working principle; it also describes the camera's ground calibration tests and their results, and provides a reference for processing the camera's scientific data and for future applications.

Heavy metals have a great influence on the deNOx efficiency of catalysts. The 3Mn10Fe/Ni catalyst that used nickel foam (Ni) as the carrier, Mn and Fe as the active components, and Co as a trace auxiliary was prepared using an impregnation method. The catalysts poisoned by Pb or Zn and Co-modified catalysts with Pb or Zn poisoning were studied. The addition of Pb or Zn significantly decreases the deNOx activity of the 3Mn10Fe/Ni catalyst due to the decrease in the content of high-valence metal elements such as Fe3+ and Mn4+, lattice oxygen concentration, reduction performance, acidity, and the number of acid sites. However, after Co modification, the deNOx activity of the poisoned catalysts can be improved effectively because the strong interaction between Pb or Zn and lattice oxygen is weakened, and the contents of lattice oxygen, high valence metal elements, reduction ability, and the number of acid sites increase.

Alkaline K poisoned and Co-modified catalysts were prepared using Fe and Mn as active components, nickel foam as a carrier, and Co as a trace additive. The de-NOx performance of the 3Mn10Fe/Ni catalyst under alkaline K poisoning conditions and the effect of Co modification on K resistance were studied. The results show that after the addition of K, the synergistic effect between Ni and Mn/Fe weakens, and the redox capability decreases, due to the decrease in NiO/Ni, Fe3+, Mn4+, lattice oxygen ratio, unsaturated Ni atom content on the catalyst surface and structure defects of Ni–Mn/Fe composite oxides. Bronsted acid sites decrease significantly, which decreases the low temperature de-NOx activity of the catalyst. The NiO/Ni ratio, Fe3+, Mn4+, and lattice oxygen content increase after Co modified the 0.3K3Mn10Fe/Ni catalyst. The synergistic effect between Ni and Mn/Fe increases, and the redox capability is also promoted. Owing to the significant increase in Bronsted acid sites, the K poisoning resistance of the 3Mn10Fe/Ni catalyst also increases dramatically. When the Co addition amount is 0.2%, the optimal K resistance property of the 3Mn10Fe/Ni catalyst was achieved, and its de-NOx activity reached 98% at 220 °C.

Chang'e-3 was China's first soft-landing lunar probe that achieved a successful roving exploration on the Moon. A topography camera functioning as the lander's "eye" was one of the main scientific payloads installed on the lander. It was composed of a camera probe, an electronic component that performed image compression, and a cable assembly. Its exploration mission was to obtain optical images of the lunar topography in the landing zone for investigation and research. It also observed rover movement on the lunar surface and finished taking pictures of the lander and rover. After starting up successfully, the topography camera obtained static images and video of rover movement from different directions, 360 degrees panoramic pictures of the lunar surface around the lander from multiple angles, and numerous pictures of the Earth. All images of the rover, lunar surface, and the Earth were clear, and those of the Chinese national flag were recorded in true color. This paper describes the exploration mission, system design, working principle, quality assessment of image compression, and color correction of the topography camera. Finally, test results from the lunar surface are provided to serve as a reference for scientific data processing and application.

Doppler asymmetric spatial heterodyne spectroscopy (DASH) technique has developed rapidly in passive Doppler-shift measurements of atmospheric emission lines over the last decade. With the advantages of high phase shift sensitivity, compact, and rugged structure, DASH is proposed to be used for celestial autonomous navigation based on Doppler radial velocity measurement in this work. Unlike atmospheric emission lines, almost all targeted lines in the research field of deep-space exploration are the absorption lines of stars, so a mathematical model for the Doppler-shift measurements of absorption lines with a DASH interferometer is established. According to the analysis of the components of the interferogram received by the detector array, we find that the interferogram generated only by absorption lines in a passband can be extracted and processed by a method similar to the approach to studying the emission lines. In the end, numerical simulation experiments of Doppler-shift measurements of absorption lines are carried out. The simulation results show that the relative errors of the retrieved speeds are less than 0.7% under ideal conditions, proving the feasibility of measuring Doppler shifts of absorption lines by DASH instruments.

The terrain camera (TCAM) and panoramic camera (PCAM) are two of the major scientific payloads installed on the lander and rover of the Chang'e 3 mission respectively. They both use a Bayer color filter array covering CMOS sensor to capture color images of the Moon's surface. RGB values of the original images are related to these two kinds of cameras. There is an obvious color difference compared with human visual perception. This paper follows standards published by the International Commission on Illumination to establish a color correction model, designs the ground calibration experiment and obtains the color correction coefficient. The image quality has been significantly improved and there is no obvious color difference in the corrected images. Ground experimental results show that: (1) Compared with uncorrected images, the average color difference of TCAM is 4.30, which has been reduced by 62.1%. (2) The average color differences of the left and right cameras in PCAM are 4.14 and 4.16, which have been reduced by 68.3% and 67.6% respectively.

We report a joint theoretical and experiment analysis of an industrial cold-storage unit for a large-scale poultry processing enterprise in the Central Plains Economic Zone of China. The flow field inside the unit was analyzed using computational fluid dynamics, which identified an optimum forced air supply of 2.05 m s-1. The defrosting cycle was then optimized experimentally, resulting in an improved defrosting method and a monthly saving of 5,530 RMB in electricity costs. Furthermore, we achieved a reduction in the temperature variation of 1.82% and in the coefficient of performance variation of 1.89%. The refrigerating capacity and electricity costs per unit of production were decreased by 8.30% and 10.20%, respectively.