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Low infrared emissivity coating with good thermal resistance was prepared by using Ni20Cr alloy particles and inorganic silicate as pigments and binders, respectively. The effects of size, shape, and annealing temperature of Ni20Cr alloy particles on infrared emissivity of the coatings were systematically investigated. The results indicate that the composite coatings can exhibit low emissivity (0.49) and good thermal stability property. Ni20Cr alloy particles with tens of micron-sized, flaky, and fine crystal structure can be propitious for decreasing the infrared emissivity of the composite coatings. In addition, the thermal stability properties of the composite coatings were measured in air to explore the effect of high-temperature environment on the infrared emissivity. The measured results show that the composite coatings can exhibit a favorable thermal stability property below 800 °C and still possess low emissivity when the test temperature is below 500 °C, due to the Si–O–Si cross-linking network structure and the mechanical interlocking between the coating and substrate.

Since the environment for the CBM development in China has been changing in recent years, it is necessary to re-consider the relevant strategies. Through investigations, surveys, geologic assessment, strategic decision-making and other techniques, the strategies for CBM development in China were discussed in respect to present situations, opportunities, challenges, proved reserves, producing reserves, strategic principles, strategic countermeasures, time-spatial allocation of strategies, risk assessments, and elimination of relevant risks. Some research results were obtained. Firstly, still in its initial development stage with fast growth, the CBM industry in China has made outstanding achievements in six aspects and also faces challenges in six aspects. Secondly, strategic focus can be summarized as constructing six CBM production bases in Qinshui, Eastern margin of Ordos Basin, Southwest China, Changqing, Northwest China, and Northeast China, respectively, according to the principles of “steadily developing middle-high rank coals, accelerating the development of low-rank coals and strengthening the comprehensive utilization of mining gas wells”. It is expected that the producing reserves and peak-production rate will be 3–4 trillion m3 and 35–45 billion m3/a, respectively. Thirdly, major strategic risks in CBM development in China include low productivities of individual wells, improper understandings of geologic conditions, decline in investments and lack of technical reserves. To eliminate these risks, it is necessary to reinforce work in the following five aspects, namely, strengthening comprehensive exploration and development of coal-bearing formations, creating favorable environments for the development of private oil companies, expanding spaces for the growth of technical service companies, conducting more researches for the development of innovative technologies in more areas and intensifying law enforcement.