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As the only H2 resource on aircraft from the steam reforming of the jet fuels on board, catalytic steam reforming of JP-10 (one of Jet fuels) over nickel-based catalyst Ni/SBA-15 were first carried out in a fixed bed tube reactor to produce hydrogen on-site or on board. A series of Ni/SBA-15 catalysts with different Ni content (3, 5, 8 and 10.8 wt%) were prepared by a modified incipient wetness impregnation method with addition of sucrose as ligand. And the effect of operation conditions of temperature (630–700 °C), nickel loading, liquid hour space velocity (LHSV = 5, 10, 15 ml/gcat·h), steam to carbon molar ratio (S/C = 3, 5) on the catalytic activity and selectivity was investigated. It was found that 8Ni/SBA-15 was the optimal catalyst for steam reforming of JP-10 even with a higher LHSV and fuel gas concentration, and approximately 100% conversion of JP-10 with over 80% selectivity to hydrogen under the recommended experimental conditions of 680 °C, S/C of 5, LHSV of 10 ml/gcat·h. The catalytic activity of 8Ni/SBA-15 dropped slowly to 84% after 6.5 h in the stability test and the carbon deposited was less with just 6% mass loss from TGA measurement (coke deposition rate 0.01gC/gcath), which ascribed to possible reasons including confine effect of mesochannel of SBA-15, strengthened structure of mesochannels due to embeded Ni particles, and higher temperature to suppress the main carbon producing reaction.

The key technologies such as accident monitoring, installation and positioning, and signal abnormality of Nuclear Instrumentation System (hereinafter referred to as RPN) is studied in this paper. Through analyzing the requirements of post-accident monitoring laws and regulations, the compensation ionization chamber monitoring technology and fission chamber monitoring technology are deeply studied. The positioning mechanism of detector components is analyzed, and the positioning technical characteristics of “push-pull trolley type” and “bucket type” are systematically studied. The signal abnormality phenomenon is analyzed, and the equivalent circuit diagram and fault tree are established to analyze the technical causes of signal abnormality. Through the research on the key technologies, an advanced system scheme is independently realized. The independent scheme adopts fission chamber accident monitoring technology, realizes “bucket type” installation of detector components, and adopts measures such as improving gateway redundancy to ensure reliable and safe operation of the unit. The autonomous scheme has been applied to an advanced third-generation pressurized water reactor in China, and the research results have certain reference value for the research and design improvement of other reactors.

The positioning technology of nuclear instrument system (RPN) detector in nuclear power plant is researched. By analyzing the requirements of radial arrangement, axial arrangement, detector measurement, operation and maintenance, environmental conditions and so on, an advanced detector bucket positioning scheme is studied and independently formed through systematic comparison of the technical characteristics of “push-pull trolley” and “bucket” positioning. The formed positioning scheme can realize the operation and maintenance of reactor plant operation platform of detector assembly, effectively reduce the irradiation of operation and maintenance personnel and greatly reduce the layout space of the reactor plant. The positioning technology has been applied to the advanced three-generation pressurized water reactor in China. The research results have certain reference value for the positioning research and design improvement of RPN detector for other reactor types.

The Frisch-grid CdZnTe detector is a kind of unipolar detector, which can solve the problem of low resolution of planar CdZnTe detectors caused by the poor charge transport of holes. In this paper, high-quality CdZnTe crystals grown by traveling heater method were adopted to develop Frisch-grid CdZnTe detectors. The Geant4 software was adopted to simulate the interaction process of various γ -rays in CdZnTe detectors with different thickness. The Comsol software was used to simulate the structural and material parameters on the weighting potential and energy spectra of Frisch-grid CdZnTe detectors. According to the simulation results, the Frisch-grid CdZnTe detectors were fabricated, and the energy spectra of the detectors under different bias and shaping time were studied experimentally. The 4 × 4 array module of Frisch-grid CdZnTe detectors was designed, whereby the detection efficiency and energy spectra of the array module were studied with the Rena-3 readout ASIC.

Anammox is known as a cost-effective approach to nitrogen removal from ammonium-rich wastewater. However, the eco-physiological characteristics of anammox population have not well been understood so far, which has obstructed the practical application of anammox process. In the present research work, an enrichment culture of anammox population was collected from an expanded granular sludge bed (EGSB) reactor, and the anammox activity was evaluated by various pH, temperature and reactant density, progressively. The results showed that the optimal ecological amplitude of pH and temperature for the anammox population was ranged from 7.0-7.5 and 30°C-35°C, respectively. To make anammox process more efficient, the density of NH4+-N and NO2−-N should be around 10.0 and 4.0 mmol·L−1, respectively. It was found that anammox population was more sensitive to NO2−-N density than NH4+-N density, and then NO2−-N density was proposed as a key indicator to practicing anammox process in engineering. With the findings, the present research will be significant in practicing annamox process.