The degradation and mineralization of aniline （AN） using ozone combined with Fenton reagent （O3/Fenton） in a rotating packed bed （RPB） was proposed in this study, and the process （RPB-O3/Fenton） was compared w...The degradation and mineralization of aniline （AN） using ozone combined with Fenton reagent （O3/Fenton） in a rotating packed bed （RPB） was proposed in this study, and the process （RPB-O3/Fenton） was compared with conventional O3/Fenton in a stirred tank reactor （STR-O3/Fenton） or single ozonation in an RPB （RPB-O3）, Effects of high gravity factor, H2O2 dosage, H2O2 dosing method and initial pH on the AN mineralization efficiency were investigated in the RPB-O3/Fenton process, In addition, the behavior of Fe（Ⅱ） was monitored at different H2O2 dosing methods and pH values. Finally, the optimal operation conditions were determined with high gravity factor of 100, initial pH of 5, Fe（Ⅱ） concentration of 0.8 mmol·L-1 and H2O2 dosage of 2.5 ml. Under these conditions, for aniline wastewater at the volume of I L and concentration of 200 mg· L- 1 ,a fast and thorough decay of AN was conducted in 10 min, and the TOC removal efficiency reached 89% in 60 min. The main intermediates of p-benzoquinone, nitrobenzene, maleic acid and oxalic acid were identified by liquid chromatography/mass spectroscopy （LC/MS）, and the degradation pathways of AN in RPB-O3/Fenton system were proposed based on experimental evidence. It could be envisioned that high-gravity technology combined with O3/Fenton processes would be promising in the rapid and efficient mineralization ofwastewater.展开更多
To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats wer...To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats were divided into 2 groups, 20 for normobaric, hypoxic conditions and the other 40 for hypobaric, hypoxic conditions. For each group, the pulmonary arterial pressure and carotid arterial pressure indicators of rats were examined by using the physiological multi-detector, and the pulmonary vascular changes in the structure were observed. Results： The normobaric/hypobaric hypoxic with high carbon dioxide environment can promote the formation of pulmonary hypertension and accelerate changes in pulmonary vascular remodeling, and promote the right ventricular hypertrophy. Conclusion： Clinical applications showed that the animal experimental cabin has observed and controlled accurately. The result was safe, reliable and reproducible. The cabin can successfully establish the pulmonary hypertension model in normobaric/hypobaric hypoxic with high carbon dioxide environment, and in order to study the physiological mechanism of a variety of circulation and respiratory diseases caused by lack of oxygen, which provided an experimental technology platform for clinical research.展开更多
Including information of the current road surface conditions can significantly improve the effectiveness of an AEB （automated emergency braking） system to avoid accidents or reduce the injury severity in rear-end cr...Including information of the current road surface conditions can significantly improve the effectiveness of an AEB （automated emergency braking） system to avoid accidents or reduce the injury severity in rear-end crashes. A method to estimate the friction potential based on on-board sensor information is shown in this work. This work expands the scope of existing investigations on whether the accuracy needed for the warning and intervention strategies of AEB can be reached with the proposed method. First, the bandwidth of surface conditions investigated is extended by including low friction surfaces comparable to ice. Second, situations of changing surface conditions and wheel-individual surface conditions were evaluated. Finally, estimation based on different sensor sets was conducted with regard to series application. The investigations are based on measurements performed on a proving ground. The main emphasis was placed on estimation during longitudinal driving conditions. The used sensors include advanced vehicle dynamics measurement equipment as well as standard on-board sensors of the vehicle.展开更多
Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the...Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the ISO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RMS) of vertical vibrations. However, the effect of the payload is not considerable on the RMS. Moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.展开更多
The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project （Transition Location Effect on Shock Wave Boundary Layer Interaction）. The e...The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project （Transition Location Effect on Shock Wave Boundary Layer Interaction）. The experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor profile. The two cases are investigated： without and with boundary layer tripping device. In the fwst case, boundary layer is laminar up to the shock wave, while in the second case the boundary layer is tripped by the step. Numerical results carried out by means of Fine/Turbo Numeca with Explicit Algebraic Reynolds Stress Model including transition modeling are compared with schlieren, Temperature Sensitive Paint and wake measurements. Boundary layer transition location is detected by Temperature Sensitive Paint.展开更多
In order to develop a wall function boundary condition for high-speed flows so as to reduce the grid-dependence of the simula- tion for the skin friction and heat flux, a research was performed to improve the compress...In order to develop a wall function boundary condition for high-speed flows so as to reduce the grid-dependence of the simula- tion for the skin friction and heat flux, a research was performed to improve the compressible wall function boundary condition proposed by Nichols. Values of parameters in the velocity law-of-the-wall were revised according to numerical experiments and the expression of temperature law-of-the-wall was modified based on theoretical analysis and numerical simulation. Be- sides, the formula of the heat conduction term in near-wall region was derived so that the coupling between the wall function boundary condition and CFD code was realized more accurately. Whereafter, the application study of the modified wall func- tion was carried out. The numerical case of supersonic turbulent boundary layer on a flat plate illustrated that the modified wall function produces reasonable results of skin friction and heat flux, and profiles of velocity, temperature and turbulent eddy viscosity for coarse grids with the initial wall spacing of y＋〈400, and that the modifications to the original wall function can obviously improve the simulation precision. As for the application of separation flows, it was found from the numerical cases of supersonic cavity flow and hypersonic axisymmetric compression comer that the compressible velocity law-of-the-wall originally established based on the fully-developed attached turbulent boundary layer approximately holds in the near-wall re- gion inside the separation flows, which ensures that reliable skin friction and heat flux can be given by the wall function inside the separation flows, while for the region near separation and reattachment points, the wall function gives results with a rela- tively large error, because the velocity law-of-the-wall used in the wall function takes on obvious deviation from the real ve- locity profiles near the separation and reattachment points.展开更多
基金Supported by the National Natural Science Foundations of China(U1610106)Shanxi Excellent Talent Science and Technology Innovation Project(201705D211011)+1 种基金Specialized Research Fund for Sanjin Scholars Program of Shanxi ProvinceNorth University of China Fund for Distinguished Young Scholars
文摘The degradation and mineralization of aniline （AN） using ozone combined with Fenton reagent （O3/Fenton） in a rotating packed bed （RPB） was proposed in this study, and the process （RPB-O3/Fenton） was compared with conventional O3/Fenton in a stirred tank reactor （STR-O3/Fenton） or single ozonation in an RPB （RPB-O3）, Effects of high gravity factor, H2O2 dosage, H2O2 dosing method and initial pH on the AN mineralization efficiency were investigated in the RPB-O3/Fenton process, In addition, the behavior of Fe（Ⅱ） was monitored at different H2O2 dosing methods and pH values. Finally, the optimal operation conditions were determined with high gravity factor of 100, initial pH of 5, Fe（Ⅱ） concentration of 0.8 mmol·L-1 and H2O2 dosage of 2.5 ml. Under these conditions, for aniline wastewater at the volume of I L and concentration of 200 mg· L- 1 ,a fast and thorough decay of AN was conducted in 10 min, and the TOC removal efficiency reached 89% in 60 min. The main intermediates of p-benzoquinone, nitrobenzene, maleic acid and oxalic acid were identified by liquid chromatography/mass spectroscopy （LC/MS）, and the degradation pathways of AN in RPB-O3/Fenton system were proposed based on experimental evidence. It could be envisioned that high-gravity technology combined with O3/Fenton processes would be promising in the rapid and efficient mineralization ofwastewater.
文摘To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats were divided into 2 groups, 20 for normobaric, hypoxic conditions and the other 40 for hypobaric, hypoxic conditions. For each group, the pulmonary arterial pressure and carotid arterial pressure indicators of rats were examined by using the physiological multi-detector, and the pulmonary vascular changes in the structure were observed. Results： The normobaric/hypobaric hypoxic with high carbon dioxide environment can promote the formation of pulmonary hypertension and accelerate changes in pulmonary vascular remodeling, and promote the right ventricular hypertrophy. Conclusion： Clinical applications showed that the animal experimental cabin has observed and controlled accurately. The result was safe, reliable and reproducible. The cabin can successfully establish the pulmonary hypertension model in normobaric/hypobaric hypoxic with high carbon dioxide environment, and in order to study the physiological mechanism of a variety of circulation and respiratory diseases caused by lack of oxygen, which provided an experimental technology platform for clinical research.
文摘Including information of the current road surface conditions can significantly improve the effectiveness of an AEB （automated emergency braking） system to avoid accidents or reduce the injury severity in rear-end crashes. A method to estimate the friction potential based on on-board sensor information is shown in this work. This work expands the scope of existing investigations on whether the accuracy needed for the warning and intervention strategies of AEB can be reached with the proposed method. First, the bandwidth of surface conditions investigated is extended by including low friction surfaces comparable to ice. Second, situations of changing surface conditions and wheel-individual surface conditions were evaluated. Finally, estimation based on different sensor sets was conducted with regard to series application. The investigations are based on measurements performed on a proving ground. The main emphasis was placed on estimation during longitudinal driving conditions. The used sensors include advanced vehicle dynamics measurement equipment as well as standard on-board sensors of the vehicle.
文摘Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the ISO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RMS) of vertical vibrations. However, the effect of the payload is not considerable on the RMS. Moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.
基金supported by the 7 EU framework project and was carried out within the research project with the acronym TFAST(Transition Location Effect on Shock Wave Boundary Layer Interaction)supported by CI TASK and PL-Grid Infrastructure
文摘The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project （Transition Location Effect on Shock Wave Boundary Layer Interaction）. The experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor profile. The two cases are investigated： without and with boundary layer tripping device. In the fwst case, boundary layer is laminar up to the shock wave, while in the second case the boundary layer is tripped by the step. Numerical results carried out by means of Fine/Turbo Numeca with Explicit Algebraic Reynolds Stress Model including transition modeling are compared with schlieren, Temperature Sensitive Paint and wake measurements. Boundary layer transition location is detected by Temperature Sensitive Paint.
基金supported by the National Natural Science Foundation of China(Grant No.11202014)
文摘In order to develop a wall function boundary condition for high-speed flows so as to reduce the grid-dependence of the simula- tion for the skin friction and heat flux, a research was performed to improve the compressible wall function boundary condition proposed by Nichols. Values of parameters in the velocity law-of-the-wall were revised according to numerical experiments and the expression of temperature law-of-the-wall was modified based on theoretical analysis and numerical simulation. Be- sides, the formula of the heat conduction term in near-wall region was derived so that the coupling between the wall function boundary condition and CFD code was realized more accurately. Whereafter, the application study of the modified wall func- tion was carried out. The numerical case of supersonic turbulent boundary layer on a flat plate illustrated that the modified wall function produces reasonable results of skin friction and heat flux, and profiles of velocity, temperature and turbulent eddy viscosity for coarse grids with the initial wall spacing of y＋〈400, and that the modifications to the original wall function can obviously improve the simulation precision. As for the application of separation flows, it was found from the numerical cases of supersonic cavity flow and hypersonic axisymmetric compression comer that the compressible velocity law-of-the-wall originally established based on the fully-developed attached turbulent boundary layer approximately holds in the near-wall re- gion inside the separation flows, which ensures that reliable skin friction and heat flux can be given by the wall function inside the separation flows, while for the region near separation and reattachment points, the wall function gives results with a rela- tively large error, because the velocity law-of-the-wall used in the wall function takes on obvious deviation from the real ve- locity profiles near the separation and reattachment points.
