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In the operation of direct air-cooled units, there are many factors that affect the safety and economy of the unit. The “hot air recirculation” and “backfill” phenomena caused by lateral wind, the influence of high ambient wind on the heat transfer performance of the air cooling unit near the windshield wall, and the “hot air recirculation” phenomenon caused by the back wind of the furnace, these may affect the direct air cooling unit. Safe and economical operation. Through carrying out on-site test research, collecting the actual operating conditions of the unit operation, the organic combination of laboratory simulation data and actual data is provided to provide a strong basis for the development of corresponding technologies.

We first consider the zeros of a big class generalized q-difference polynomials in entire function which come from the Hayman problem. Second, we research about uniqueness result of the class q-difference polynomials in entire function which share a value. Our results improved or generalize the previous known results.

In this paper, we find the entire solutions of two classes of nonlinear difference equations when the solution is an exponential polynomial by using the new obtained Clunie Lemma. Some examples are given to show the existence of the solutions.

This project takes the flue at the tail of Fujian Kemen Power Generation Company as the research object. Calibration factor, precise flow value, etc. Through the above analysis, it is concluded that the ultrasonic flowmeter has high requirements on the location selection, and the measurement result is closer to the true value. The matrix type flowmeter is easy to arrange, and the location selection sensitivity is low; the single point pitot tube flowmeter has poor accuracy and is not recommended.

The experimental bench for the pyrolysis characteristics of single droplets of urea solution was established to analyze the variation characteristics of the whole process of single droplet evaporation pyrolysis. The results show that there are a large number of bubbles in the droplets which are very favorable for pyrolysis, the pyrolysis energy and atomization degree are insufficient, leading to the formation of intermediate products, greatly reducing the efficiency of denitrification. Based on the experimental data, the urea pyrolysis system was developed and designed for the SCR denitrification project of a coal-fired boiler in a thermal power plant, and key equipment was optimized, including urea storage and supply system, denitration reactor system, spray gun device, pyrolysis furnace body, etc. The system was put into operation. After that, the NOx concentration was reduced from 250mg/Nm3 to 20 mg/Nm3, and the denitration efficiency reached over 90%. The project has strong engineering application value.

The Sanjiangyuan area is famous as the Chinese water tower, it is a transition zone of semi-humid, semi-arid and arid area. An area of about 400,000 square kilometers and the water source of billions of people, also the ecological barrier of the whole of Asia's economic and social development.Based on the daily rainfall data of 13 meteorological stations in Sanjiangyuan area from 1985 to 2015, the rainfall indexes such as the rainy season from the beginning and the ending of the rainy season were extracted. And the trend of rainy season in the study area was analyzed. The results show that the daily rainfall in the Sanjiangyuan area accounts for more than 50% of the annual rainfall; the onset of the rainy season in the eastern part of Sanjiangyuan has a delayed trend and the central area has a tendency to advance; the number of days in the rainy season has decreased in the past 30 years, reduced 4d. There is a positive correlation between the starting date of rainy season and the average rainfall in the rainy season. The changes of these rainy seasons are of great significance to the economic development and ecological protection of the region.

In this paper, the influence of the active layer nanomorphology on device performance for ternary PbS(x)Se(1-x) quantum dot-based solution-processed infrared photodetector is presented. Firstly, ternary PbS(x)Se(1-x) quantum dots (QDs) in various chemical composition were synthesized and the bandgap of the ternary PbS(x)Se(1-x) QDs can be controlled by the component ratio of S/(S + Se), and then field-effect transistor (FET) based photodetectors Au/PbS0.4Se0.6:P3HT/PMMA/Al, in which ternary PbS0.4Se0.6 QDs doped with poly(3-hexylthiophene) (P3HT) act as the active layer and poly(methyl methacrylate) (PMMA) as the dielectric layer, were presented. By changing the weight ratio of P3HT to PbS0.4Se0.6 QDs (K = M(P3HT):M(QDs)) in dichlorobenzene solution, we found that the device with K = 2:1 shows optimal electrical property in dark; however, the device with K = 1:2 demonstrated optimal performance under illumination, showing a maximum responsivity and specific detectivity of 55.98 mA W(-1) and 1.02 × 10(10) Jones, respectively, at low V(DS) = -10 V and V(G) = 3 V under 980 nm laser with an illumination intensity of 0.1 mW cm(-2). By measuring the atomic force microscopy phase images of PbS0.4Se0.6:P3HT films in different weight ratio K, our experimental data show that the active layer nanomorphology has a great influence on the device performance. Also, it provides an easy way to fabricate high performance solution-processed infrared photodetector.