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As a result of incorrect operation causing the stall of primary fan, the pressure of primary air continuously decreased. Therefore, the combustion stability in boiler has been disturbanced greatly, and the generation unit trips due to water-coal ratio imbalance. In this paper, the stall accident resulted from incorrect operation have been analyzed, and correct operation for the fan have been put forward. Namely, the precursory phenomena of stall can be found and eliminated. Correct operations can keep the pressure of primary air stable. It is concluded that adopting the suitable water-coal ratio and air-coal ratio are helpful to keep the unit on safe.

The supercritical turbine, changed low pressure rotor’s blade in site, bear vibration over-proof seriously because of unbalance, reached rated speed after dynamic balance in site. The vibration of low pressure Ⅱshaft’s bear was still over-proof. And the bear vibration phase was anti-phase with the shaft vibration not only anti-phase but also in-phase. It was found that the bear vibration was highly related with the anti-phase component of shaft vibration after running date analysis. And the bear vibration was reduced obviously after the anti-phase component of shaft’s residual unbalanced mass reduced by dynamic balance in site.

Braided composite tubular structures are of interest as viable energy absorbing components to improve vehicle passive safety. Unfortunately, there are many difficulties in predicting the crash response of braided composite tubes. In this study, a progressive failure model for braided composite materials, which had been implemented as a user material model in ABAQUS/Explicit, was used to simulate the axial crash response of braided composite tubes. It was shown that the model adequately captured the failure characteristics (such as matrix cracking, fiber fracturing and delamination) and energy absorption of braided composite tubes under axial compression. In addition, the simulation results show that braided composites have higher energy absorption performance compared to traditional metals.

The energy flow process in iron & steel factory is composed of the production, conversion, using of all sorts of energy and waste gas removing. In accordance with the energy flow process, make use of the law of energy conservation and conversion, the energy flow diagram from the energy-consumption analysis, and it is constructed. The energy flow analysis model of iron & steel is designed based on the energy flow diagram. To adopt comparison method, the influence of each process energy-consumption on the energy consumption of iron and steel enterprise also discussed.

Related to the technological field of Photographing and Shooting Support Device, a Photographing and Shooting Device Delivery System includes shooting track and its Device Case. A shooting track covers at least a set of track-flexible track units. Each single unit in the meantime owns two main tracks and at least two horizontal track axes which inset between the two main tracks. The horizontal track axis can meet the needs of the length-adjustment devices in stretching out and drawing back the length of axes. A single Shooting Track Device Case consists of a Roker, Case itself, two Pulley Mechanisms that attached to the bottom of the Case, as well as a position device that has the Rocker fixed. The Rocker can take apart and connect with the Case through Position Device. At least one axis moving mechanism is attached to the Pulley Mechanism Device, which can collapse the length in order to the change of axis. In doing so, it will not only cut down the expense but also save labor. By replacing the tripod spider in positioning through the Rocker, it can boost enormous convenience, make shooting in a low angle into a reality, and occupies relatively a smaller space compared with the tripod spider.

Photodegradation ofp-nitrophenol catalyzed by ZnO/MWCNTs composite in water was investigated. The effects of pH, irradiation time, catalyst loading, initial substrate concentration and MWCNTs content on the degradation were investigated. Experiment results revealed that the optimal conditions were ap-nitrophenol concentration of 60.0 mg/L at pH 5.0 with catalyst loading of 10.0 g/L under solar irradiation for the illumination of 180 min. The highest efficiency on photodegradation ofp-nitrophenol can be achieved with an optimal MWCNTs/ZnO mass ratio of 0.16%. Possible decomposing mechanisms were also discussed. The repeatability of photocatalytic activity was tested. The photocatalyst was used ten cycles with degradation efficiency still higher than 95%. The results of the study showed the feasible and potential use of ZnO/MWCNTs composite in degradation of toxic organic pollutants.

Carbon dioxide curing was adopted to accelerate the hydration of foam concrete samples with a lower bulk density level of around 450 kg/m3 and a higher level of around 1150 kg/m3. The bending strength, compressive strength and ultrasonic transmission velocity of carbonated harden foam concrete were tested, the hydration products were analyzed by means of XRD and TG/DSC. The results show as: (1) By comparing with standard curing samples, there are more than 47% increments of specific strengths of carbonated foam concrete with the higher density level at a certain curing time before 14d. However, for the lower density level one, there is just a significant improvement of specific bending strength obtained before 7d. (2) The carbonated foam concretes with the lower density level show lower ultrasonic transmission velocity than standard curing ones. The velocities have hardly difference for both carbonated and standard curing samples with the higher density level. (3) Vaterite can’t be found in carbonated foam concrete with the lower density level at curing time before 28d, while it becomes a common phase in 3d’s carbonated sample with the higher density level. Vaterite was considered to be an important factor that influences the ultrasonic transmission velocity.

Carbonation curing was adopted to accelerate the hydration of foam concrete with lower density of around 450 kg/m3. After standard curing in mold for 2d, the foam concrete samples were marked into two groups. The first one is directly cured in ‘Carbonation Test Chamber for Concrete’ with CO2 concentration 20%, RH 70% and temperature 20°C (it was called ‘carbonation curing’) for 3d to 56d. The second one is cured in ‘Standard Curing Room for Concrete’ with RH ≥95% and temperature 20°C (it was called ‘standard curing’) for 7d, and then at carbonation curing for 3d, 7d and 21d. The strengths of harden foam concrete were tested, the hydration products were analyzed by means of XRD and TG/DSC. The results were compared with those of standard curing samples. It indicates that foam concrete with lower density is easier to be carbonated; the hydration of both C3S and C2S accelerates by carbonation curing, which results in higher early strength improvement. Vaterite is popular in the second group of samples, while it only appears in the first group of sample with longer carbonation time of 56d. Vaterite was considered to be formed from the further carbonation of CxSHy.

Formation of sulfuric acid aerosol form a binary mixture of sulfuric acid and water is one of the most important process of secondary particles formation in troposphere, which can seriously affect the atmospheric radiation balance and climate change directly or indirectly, therefore, in this research, secondary aerosol generation by photo oxidation by UV of SO2 containing model air in a flow reactor was investigated experimentally, and the particle size distribution was measured by differential mobility analyzer and Faraday cup electrometer (DMA-FCE) system. Experiments were carried out at various ambient pressure and residence time, and the temperature of reactor was kept at 25, the experiment aims to find out the impact of pressure on this system. The results showed that in low pressure, the growth of aerosol particles was enhanced due to the increase of Brownian coagulation coefficient.