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This study investigates the use of calcium-based slurry for simultaneous removal NO and SO2 from oxy-fuel combustion flue gas, and recovery of the sulfur and nitrogen species in resulting solutions. The experiments were performed in a bubbling reactor in a transient mode under the pressure of 20 bar. The various influencing factors including the CaO amount, carrier gas (N2/CO2), and absorption time on the simultaneous NO and SO2 removal process, and the solution products were studied comprehensively. The results show that the NO2 removal efficiency can be improved by the presence of CO2, and the gas phase HNO2 produces in this process. The addition of CaO has positive effects not only on the NO2 removal efficiency but also on the formation of stable HNO3. With the presence of CO2, CaCO3 is formed in a solution initially. With the decrease of pH, CaCO3 is gradually converted to CaSO4, and in particular CaCO3 can be fully avoided through decreasing the pH of an absorption solution to 1.14. At the same time, the formation of unstable S(IV) and NO2- can be prevented when the solution pH is lower than 1.37. The nitrogen and sulfur compounds in the absorption solution (at pH 1.14) were further separated by the addition of different amounts of CaO. In particular, 95% of SO42- finally can be recovered in the form of CaSO4.2H2O with nitrogen in solution existing as NO3- by controlling the Ca/S ratio at 4.70. The effectiveness of calcium-based slurry on the removal and recovery of SO2 and NO is confirmed.

In order to solve the problems of inaccurate and untimely monitoring and high false alarm rate in the current monitoring of the tower pole tilt attitude, this paper proposes a technology for monitoring the tower pole tilt attitude based on RTK technology of Beidou reverse network. This method uses reverse network RTK differential positioning algorithm, which can improve the positioning accuracy of the low-cost Beidou/GNSS positioning terminal and make the positioning accuracy of the tower pole tilt monitoring reach the millimeter level. In this paper, the tilt attitude information of the transmission line tower is measured and calculated by using the height and position information of the transmission line tower, and then the risk assessment is carried out, so as to control the tilt attitude and assess the risk of the transmission line tower. The actual test results show that the method can obtain the information of the tilt attitude of transmission tower pole accurately and reliably, and can be used to evaluate it, which meets the requirements of intelligent, accurate and digital management.

Gasoline, as one of the flammable liquids, is used commonly in arson. Due to its typical fluidity and permeability, particular burn patterns can be formed in fire scene. In order to provide references for fire investigators to collect trace evidences and identify fire cause accurately, the burn patterns on different flooring materials are investigated in this paper. Two polymer flooring materials (Polypropylene fiber and Polyvinyl chloride coil) were selected in the experiments to study the burn pattern characteristics by simulating the fire scene. By comparing the difference of the burning pattern with and without gasoline, rules of pattern characteristics on different material surface have been summarized. Meanwhile, fire extinguishing style was considered in this work. The results show that the burn pattern characteristics become remarkably different when the flooring materials loaded by gasoline. In addition, fire extinguishing style has a great impact on the burn patterns, such as the carbonized degree, the residual shape and the fire traces. It is believed that the results in this paper would provide important guidance for investigation on arson which applied gasoline as the combustion improver.

To reduce the error and faster classification by mechanizing in classifying the potato shape and size through machine vision using the extraction of characters procedure to identify the size, and using the shape detection procedure to identify the shape. Test results in potato size detection revealed 40/191 = 0.210mm/pixel as length scale or calibration factor (40/M) where 40 is the table tennis ball size (40mm) and 191 as image pixels table tennis (M); measurement results revealed that between the algorithm results and the manual measurements, the absolute error was

Carbon Capture, Utilization and Storage (CCUS) is one of the key technologies for realizing large-scale low-carbon utilization of coal-fired power plants in service. How to evaluate its economics is crucial to the decision-making of traditional coal-fired power enterprises. This paper analyzes the changes in the physical, emission and economic parameters of in-service coal-fired power plants without and with the CCUS retrofit. A method for evaluating the economic feasibility of coal-fired power plants retrofitting based on net cash flow is proposed, which compares the impact of CCUS retrofit on the net present value of the remaining life cycle of the power plant. The impact of uncertain parameters such as carbon dioxide sales unit price, carbon capture device operating cost, free carbon quota, and carbon emission right price on the evaluation results are analyzed.

Air pollution in Beijing-Tianjin-Hebei region has caused widespread concern. In winter, the combustion of fossil fuel produces a very high proportion of fine particulate matter in the air. However, the vegetation coverage is relatively low. The dust retention of evergreen plants is particularly important for improving air quality. In this study, five evergreen species were selected, and the effects of leaf stomatal characteristics (stomatal width, stomatal length and stomatal density) of greening plants in winter on leaf dust retention were explored. The results showed that: (1) The highest percentage of PM10, PM2.5, and PM1 were retained by Yucca gloriosa, followed by Buxus sinica and Phyllostachys propinqua (2) There was a positive correlation between stomatal density, stomatal width and TSTP, while the correlation between stomatal length and TSTP was low. Our study can provide scientific guidance for plant planning to improve urban air pollution.

With the acceleration of urbanization, air pollution is getting worse especially during winter, which causes serious threat to people’s health. Large numbers of studies showed that green plants had a significant species on the retention of particulate matters. In view of this, this study selected five evergreen plants to explore the dust retention amounts of PM10, PM2.5, PM1 per unit leaf area and the microstructure of leaf surface. The results showed that: 1. Within the unit leaf area: the dust retention amount (PM10, PM2.5, PM1) of Yucca gloriosa was the highest, followed by Buxus sinica, and that of Ligustrum lucidum, Buxus megistophylla and Phyllostachys propinqua was relatively few. 2. The roughness of the leaf surface, the waxy layer, the stomata protruded, the number of stomata, stomata density, and stomatal opening and closing degree would affect the retention of particulate matter. The results obtained scientific guidance for plants collection in landscape greening with brilliant dust retention ability, and maximized the ecological effect of greening plants to mitigate air pollution.

The key problem for flanging forming of square tributary junction on spherical shell is to determine the shape and sizes of prefabricated hole. In order to investigate precise shape and sizes of the prefabricated hole, an optimized design model was established. The flanging forming process was simulated using the software of FE-simulation and the target function for optimized design was calculated based on results of the simulations. In order to increase the convergence rate of the optimized design, a mathematical model of prefabricated hole for flanging forming on spherical shell was established, the results were used as initial values for optimized design. To verify its accuracy, the optimized design was carried out on a typical flanging forming of square tributary junction on spherical shell. The results of the optimized design meet the technological requirements.