Since the impounding of the Three Gorges Reservoir, the channel of the Yangtze River has become a busy watercourse and the probability of landslide-induced tsunamis has increased. In the case of landslide-induced tsun...Since the impounding of the Three Gorges Reservoir, the channel of the Yangtze River has become a busy watercourse and the probability of landslide-induced tsunamis has increased. In the case of landslide-induced tsunamis in the Three Gorges Reservoir, even after shipping closures in advance,there are still facilities and objects in urgent need of protection within the risk zone of the watercourse,such as wharfs, marine fueling stations, berthed ships.The emergency protection against and decay of landslide-induced tsunamis in inland watercourses is a new challenge. In this study, 37 sets of wave decay experiments were conducted with the hydromechanics numerical method. The wave decay efficiencies of common simple structures including submerged horizontal plate, horizontal plate on the water surface,inclined thin plate and cross-plates in coastal areas were compared and analyzed. Cross-plates structure showed better wave decay capacity than other simple plates. The wave decay performance of cross-plates was related to five modes of energy dissipation and transformation, namely run-up/run-down, overtopping,reflecting, return flow and disturbed wave orbital path. The type of wave had little relation with the decay performance of cross-plates, but a strong correlation with cross-plates structure, especially the height of the vertical emerged plate. The best decay performance was observed when the ratio of wave amplitude to emerged vertical plate height was between 1 and 1.5, which can reduce up to about 80%of the incoming wave amplitude. Finally, the emergency way of cross-plates applied to the decay of landslide-induced tsunami in river course is discussed.This study provides a conceptual reference for related studies to practice the attenuation of landslide-induced tsunami in reservoirs.展开更多
[ Objective] To observe sub-chronic toxicity of Tephrosia canadida DC. in mice and thus to evaluate their safety to be used as protein feed resources. [ Methed]Sixty-four 6-week-old healthy Kunming mice weighing about...[ Objective] To observe sub-chronic toxicity of Tephrosia canadida DC. in mice and thus to evaluate their safety to be used as protein feed resources. [ Methed]Sixty-four 6-week-old healthy Kunming mice weighing about 25 g were randomly divided into four groups （ n = 16）, half male and half female. Mass ratios of basic diet to leaf meal of Tephrosia canadida DC. in group A, group B, group C and group D were 10：0, 4：1, 3：2 and 2：3, respectively. After 35-d feeding, the effects of Tephrosia canadida DC. on growth, blood and organs of mice were observed. [ Resultl Dudng the trial, all mice had normal activities, and no death and no abnormal blood index were observed. All organs of the mice in the experimental groups had no visible pathological lesion, and organ indexes had no significant difference between the experimental groups and the control group. Except that slightly abnormal histological changes appeared in liver and kidney of the mice in the group C and D, no histological change was ob- served in other organs of the experimental mice. [ Conclusion] Tephrosia canadida DC. have no adverse effects on mice, which provides a refer- ence for research about their safety in feed of other animals.展开更多
This paper compares analytical and numerical methods by taking the forecasting of water yield of deep-buried iron mine in Yanzhou, Shandong as an example. Regarding the analytical method, the equation of infinite and ...This paper compares analytical and numerical methods by taking the forecasting of water yield of deep-buried iron mine in Yanzhou, Shandong as an example. Regarding the analytical method, the equation of infinite and bilateral water inflow boundary is used to forecast the water yield, and in the case of numerical simulation, we employed the GMS software to establish a model and further to forecast the water yield. On the one hand, through applying the analytical method, the maximum water yield of mine 1 500 m deep below the surface was calculated to be 13 645.17 m3/d; on the other hand, through adopting the numerical method, we obtained the predicted result of 3 816.16 m3/d. Meanwhile, by using the boundary generalization in the above-mentioned two methods, and through a comparative analysis of the actual hydro-geological conditions in this deep-buried mine, which also concerns the advantages and disadvantages of the two methods respectively, this paper draws the conclusion that the analytical method is only applicable in ideal conditions, but numerical method is eligible to be used in complex hydro-geological conditions. Therefore, it is more applicable to employ the numerical method to forecast water yield of deep-buried iron mine in Yanzhou, Shandong.展开更多
基金funded by the National Natural Science Foundation Project of China(41372321)China Geological Survey Project(121201009000150018)
文摘Since the impounding of the Three Gorges Reservoir, the channel of the Yangtze River has become a busy watercourse and the probability of landslide-induced tsunamis has increased. In the case of landslide-induced tsunamis in the Three Gorges Reservoir, even after shipping closures in advance,there are still facilities and objects in urgent need of protection within the risk zone of the watercourse,such as wharfs, marine fueling stations, berthed ships.The emergency protection against and decay of landslide-induced tsunamis in inland watercourses is a new challenge. In this study, 37 sets of wave decay experiments were conducted with the hydromechanics numerical method. The wave decay efficiencies of common simple structures including submerged horizontal plate, horizontal plate on the water surface,inclined thin plate and cross-plates in coastal areas were compared and analyzed. Cross-plates structure showed better wave decay capacity than other simple plates. The wave decay performance of cross-plates was related to five modes of energy dissipation and transformation, namely run-up/run-down, overtopping,reflecting, return flow and disturbed wave orbital path. The type of wave had little relation with the decay performance of cross-plates, but a strong correlation with cross-plates structure, especially the height of the vertical emerged plate. The best decay performance was observed when the ratio of wave amplitude to emerged vertical plate height was between 1 and 1.5, which can reduce up to about 80%of the incoming wave amplitude. Finally, the emergency way of cross-plates applied to the decay of landslide-induced tsunami in river course is discussed.This study provides a conceptual reference for related studies to practice the attenuation of landslide-induced tsunami in reservoirs.
文摘[ Objective] To observe sub-chronic toxicity of Tephrosia canadida DC. in mice and thus to evaluate their safety to be used as protein feed resources. [ Methed]Sixty-four 6-week-old healthy Kunming mice weighing about 25 g were randomly divided into four groups （ n = 16）, half male and half female. Mass ratios of basic diet to leaf meal of Tephrosia canadida DC. in group A, group B, group C and group D were 10：0, 4：1, 3：2 and 2：3, respectively. After 35-d feeding, the effects of Tephrosia canadida DC. on growth, blood and organs of mice were observed. [ Resultl Dudng the trial, all mice had normal activities, and no death and no abnormal blood index were observed. All organs of the mice in the experimental groups had no visible pathological lesion, and organ indexes had no significant difference between the experimental groups and the control group. Except that slightly abnormal histological changes appeared in liver and kidney of the mice in the group C and D, no histological change was ob- served in other organs of the experimental mice. [ Conclusion] Tephrosia canadida DC. have no adverse effects on mice, which provides a refer- ence for research about their safety in feed of other animals.
文摘This paper compares analytical and numerical methods by taking the forecasting of water yield of deep-buried iron mine in Yanzhou, Shandong as an example. Regarding the analytical method, the equation of infinite and bilateral water inflow boundary is used to forecast the water yield, and in the case of numerical simulation, we employed the GMS software to establish a model and further to forecast the water yield. On the one hand, through applying the analytical method, the maximum water yield of mine 1 500 m deep below the surface was calculated to be 13 645.17 m3/d; on the other hand, through adopting the numerical method, we obtained the predicted result of 3 816.16 m3/d. Meanwhile, by using the boundary generalization in the above-mentioned two methods, and through a comparative analysis of the actual hydro-geological conditions in this deep-buried mine, which also concerns the advantages and disadvantages of the two methods respectively, this paper draws the conclusion that the analytical method is only applicable in ideal conditions, but numerical method is eligible to be used in complex hydro-geological conditions. Therefore, it is more applicable to employ the numerical method to forecast water yield of deep-buried iron mine in Yanzhou, Shandong.
