A high energy digital radiography （DR） testing system has generated diverse scientific and technological interest in the field of industrial non-destructive testing. However, due to the limitations of manufac-turing...
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A high energy digital radiography （DR） testing system has generated diverse scientific and technological interest in the field of industrial non-destructive testing. However, due to the limitations of manufac-turing technology for accelerators, an energy fluctuation of the X-ray beam exists and leads to bright and dark streak artifacts in the DR image. Here we report the utilization of a new software-based method to correct the fluctuation artifacts. The correction method is performed using a high pass filtering operation to extract the high frequency information that reflects the X-ray beam energy fluctuation, and then subtracting it from the original image. Our experimental results show that this method is able to rule out the artifacts effectively and is readily implemented on a practical scanning system.
α-Fe2O3 nanorod arrays were fabricated by a low-temperature aqueous chemical growth (ACG) technique and followed by an annealing process. For the surface doping of α-Fe2O3 nanorods, β-FeOOH nanorods obtained via AC...
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Radiation distribution study is of importance for the design and the optimization of fluidized photocatalytic tubular reactor which has been developed for photocatalytic hydrogen production under direct solar light. I...
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Radiation distribution study is of importance for the design and the optimization of fluidized photocatalytic tubular reactor which has been developed for photocatalytic hydrogen production under direct solar light. In the present study, the radiation distribution in such reactor was successfully simulated by adopting Monte Carlo method and the six-flux radiation absorption-scattering models. Both the incident angles of light around the reactor and the concentration distribution of photocatalyst were taken into account. Our analysis indicates that the angles and the intensity of the incident rays significantly affect the radiation distribution. Moreover, it was also found that the equilibrium radiation distribution has a close relationship with the density distribution of the photocatalysts. The simulated results are expected to be helpful for obtaining the optimal operating parameters for solar photocatalytic hydrogen production.
A model for wave properties, such as wave velocity and amplitude in churn flow has been developed in this paper. The results demonstrate that the wave behavior differs from that in annular flow. In addition, the criti...
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A model for wave properties, such as wave velocity and amplitude in churn flow has been developed in this paper. The results demonstrate that the wave behavior differs from that in annular flow. In addition, the critical amplitude A c decreases with the increase in gas flow rate. Moreover, the maximum amplitude A max decreases with the increasing of gas mass flux but increase with the increasing of liquid mass flux. The average absolute deviations (AAD) for A c and A max are 16.29% and 7.10%, respectively.
In order to improve the accuracy of interface capturing and keeping the computational efficiency, an adaptive VOF method on unstructured grid is proposed in this paper. The volume fraction in each cell is regarded as ...
In order to improve the accuracy of interface capturing and keeping the computational efficiency, an adaptive VOF method on unstructured grid is proposed in this paper. The volume fraction in each cell is regarded as the criterion to locally refine the interface cell. With the movement of interface, new interface cells (0 ≤ f ≤ 1) are subdivided into child cells, while those child cells that no longer contain interface will be merged back into the original parent cell. In order to avoid the complicated redistribution of volume fraction during the subdivision and amalgamation procedure, a predictor‐corrector algorithm is proposed to implement the subdivision and amalgamation procedures only in empty or full cell ( f = 0 or 1). Thus volume fraction in the new cell can take the value from the original cell directly, and the interpolation of the interface is avoided. The advantage of this method is that the re‐generation of the whole grid system is not necessary, so its implementation is very efficient. Moreover, an advection flow test of a hollow square was performed, and the relative shape error of the result obtained by adaptive mesh is smaller than those by non‐refined grid, which verifies the validation of our method.
Radiation distribution study is of importance for the design and the optimization of fluidized photocatalytic tubular reactor which has been developed for photocatalytic hydrogen production under direct solar light. I...
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Radiation distribution study is of importance for the design and the optimization of fluidized photocatalytic tubular reactor which has been developed for photocatalytic hydrogen production under direct solar light. In the present study, the radiation distribution in such reactor was successfully simulated by adopting Monte Carlo method and the six-flux radiation absorption-scattering models. Both the incident angles of light around the reactor and the concentration distribution of photocatalyst were taken into account. Our analysis indicates that the angles and the intensity of the incident rays significantly affect the radiation distribution. Moreover, it was also found that the equilibrium radiation distribution has a close relationship with the density distribution of the photocatalysts. The simulated results are expected to be helpful for obtaining the optimal operating parameters for solar photocatalytic hydrogen production.
Nickel and antimony doped tin dioxide (NATO) coated titanium electrodes are prepared and tested for electrochemical treatment of pentachlorophenol (PCP). The effect of nickel content on the electrochemical activity is...
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Nickel and antimony doped tin dioxide (NATO) coated titanium electrodes are prepared and tested for electrochemical treatment of pentachlorophenol (PCP). The effect of nickel content on the electrochemical activity is studied using PCP as target organic waste. The nickel content has an optimized value for the activity. The NATO is characterized and the relationship between activity and oxygen to tin atomic ratio is discussed.
The present work reports the renewable hydrogen production by an anaerobic photocatalytic reforming of formic acid over CdS sensitized Na2Ti2O4(OH)2 nanotubes. the Na2Ti2O4(OH)2 nanotube was prepared and charactered b...
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The present work reports the renewable hydrogen production by an anaerobic photocatalytic reforming of formic acid over CdS sensitized Na2Ti2O4(OH)2 nanotubes. the Na2Ti2O4(OH)2 nanotube was prepared and charactered by X-ray diffraction, UV-visible absorption, transmission electron microscopy, etc. The activity of the catalyst in formic acid was investigated. The greatest photocatalytic reforming activity of formic acid occurs as the formic acid initial concentration is 20 v.%. A probable mechanism for the photocatalytic reforming process was proposed and discussed.
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