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Monolithic catalysts have attracted attention as a substitute for particulate catalyst beds in gas-liquid-solid three-phase reactions. In this work, carbon gel monoliths with a microhoneycomb structure (carbon gel microhoneycombs, CMHs) were synthesized, and Pt particles with an average particle diameter of 3.0 nm were supported on them in a highly dispersed state through the incipient wetness method. In addition, it was confirmed that the supported Pt shows a high resistance to sintering. Hydrogenation of p-nitrophenol was carried out in order to evaluate the catalytic activity of Pt/CMHs in three-phase reactions. As a result, Pt/CMHs showed a high catalytic activity even at ambient temperature and normal pressure. Furthermore, the hydrogenation reaction significantly proceeded even when hydrogen was provided at the minimum flow rate required to complete the reaction. Since Pt/CMHs showed higher reaction activity than the same catalyst in the form of particles, it was concluded that the efficiency of three-phase reactions can be significantly improved by using monolithic catalysts with a microhoneycomb structure.

With the continuous development of deep oil and gas, minerals, geothermal resources, and other resources, there are increasingly more stringent requirements for equipment. In particular, the ultra-high-pressure dynamic seals of deep mining device need to be developed. Therefore, considering the use of dynamic seals in unique deep mining environments, an ultra-high-pressure rotating combined dynamic seal was designed and developed and its sealing performance was experimentally measured and analyzed. The results show that the experimental device can operate stably under a pressure of up to 150 MPa and a rotating speed of 76 r/min, and can also operate normally under a rotating speed of up to 140 r/min and a sealing pressure of 120 MPa. During the operation of the ultra-high-pressure rotating combined dynamic seal, the sealing ring does not show obvious damage, which vouches for its sealing performance. No leakage of flow and pressure was detected in the all seal structures within the sealing pressure range of 0∼150 MPa. Therefore, the dynamic sealing performance of the device is intact under ultra-high-pressure conditions and can be applied in deep mining environments at a certain depth. The research and development of this device can aid future deep energy exploration and exploitation.

Pressure - and temperature-dependent luminescence properties of 3F3/2 → 4I9/2 transition of Nd3+:GdTaO4 were studied for potential applications in optical sensing. Two isolated emission lines correspond to 3F3/2(R2, 1) → 4I9/2(Z5) transitions, locates at 920 and 927 nm under ambient condition, are very sensitive to pressure with coefficients of −15.6 and −14.5 cm−1/GPa determined in a pressure range up to about 9 GPa. The luminescence intensity ratio between the two emission lines exhibits a large dependence with temperature in a range from 80 to 620 K, the corresponding temperature sensitivity at room temperature is similar to that of Nd3+:YAG. These advantages, together with the other observed features of high stable position relationship under pressure and low thermal shifts for the two emission lines indicate that, Nd3+:GdTaO4 is a promising candidate to be used as pressure and temperature sensors in the near-infrared spectral range.