A new type of airtight wall with the combination of foamed concrete and pier support was designed in this study. Based on the theories and models related to the foamed concrete and blasting shock load, using the numer...A new type of airtight wall with the combination of foamed concrete and pier support was designed in this study. Based on the theories and models related to the foamed concrete and blasting shock load, using the numerical analysis method, this study obtains the new material's mechanical and destruction laws through analyzing its reaction to different conditions of load (mining and shock waves), airtight wall thickness (1.2, 1.5, 1.8, 2.1 m) and steel pipe diameters (400, 450, 500 and 600 mm). The results show that: ①foamed concrete can have very good suspension, and the pier column support is the main carrier of roof pressure; ② the damaged area of foamed concrete decreases as the foamed concrete thickness increases. Under impact loading, the thickness of the foamed concrete wall plays a more obvious role in retaining its integrity; ③under the same mining pressure, the damage area increases as the steel pipe diameter increases; ④ with additional mining stress increase, under whether static load or impact load, the stress on the foamed concrete and steel pipe will also increase gradually, therefore the actual airtight wall design will need to be based on specific circumstances in steel stress.展开更多
Based on trajectory equations of gas bubble,an eddy-bubble interaction(EBI)model was developed. This model considered the effect of non-drag forces and took the eddy-bubble interaction time as the refreshing time scal...Based on trajectory equations of gas bubble,an eddy-bubble interaction(EBI)model was developed. This model considered the effect of non-drag forces and took the eddy-bubble interaction time as the refreshing time scale of turbulent fluctuations.The relationship between the crossing-eddy time and the eddy lifetime was discussed,and the predicted distributions of radial,axial velocities of bubbles and gas holdup were also given. Compared with eddy lifetime(EL)model,the EBI model gives somewhat smaller axial velocity in the upper circulation region and larger velocity in the lower circulation region,causing that fewer bubbles reach the lower circulation region and gas holdup becomes higher in the upper circulation region.The predicted gas holdup by the EBI model approaches closer to the experimental data in the discharge stream region.展开更多
Blistering cupping therapy, as a new type of cupping therapy, has attracted more and more attention of clinical doctor and scholars in home and abroad. Blistering cupping therapy achieves better effects through the fo...Blistering cupping therapy, as a new type of cupping therapy, has attracted more and more attention of clinical doctor and scholars in home and abroad. Blistering cupping therapy achieves better effects through the formation of blistering fluid after suction. However, it is still controversial whether cupping induced blisters are beneficial to recovery of diseases, and the mechanism is still not completely clear. Here on the basis of the traditional cupping method, we aimed to identify the mechanism of blistering cupping from the levels of biomechanics and molecular biology. The negative pressure attraction induced by cupping suck should be of value in increasing pain threshold and relieving pain as well as improving the blood circulation and metabolism. Furthermore, the blistering fluid induced by cupping was the inflammatory substance actually that discharged through the superficial lymphatic vessels, including immunoglobulin, lysozyme, erythrocytes, etc. which could cause the autogenetic inflammatory reaction of selected cupping area, and further activated certain immune pathways including anti-oxidation, anti-apoptosis, tissue repairing and metabolic regulation. Besides, the formation of scar induced by blistering cupping was not only the result of excessive inflammatory response, but also involved in mobilizing the immune response.展开更多
文摘A new type of airtight wall with the combination of foamed concrete and pier support was designed in this study. Based on the theories and models related to the foamed concrete and blasting shock load, using the numerical analysis method, this study obtains the new material's mechanical and destruction laws through analyzing its reaction to different conditions of load (mining and shock waves), airtight wall thickness (1.2, 1.5, 1.8, 2.1 m) and steel pipe diameters (400, 450, 500 and 600 mm). The results show that: ①foamed concrete can have very good suspension, and the pier column support is the main carrier of roof pressure; ② the damaged area of foamed concrete decreases as the foamed concrete thickness increases. Under impact loading, the thickness of the foamed concrete wall plays a more obvious role in retaining its integrity; ③under the same mining pressure, the damage area increases as the steel pipe diameter increases; ④ with additional mining stress increase, under whether static load or impact load, the stress on the foamed concrete and steel pipe will also increase gradually, therefore the actual airtight wall design will need to be based on specific circumstances in steel stress.
基金Supported by the National Natural Science Foundation of China(20776121) the Scientific Fund of Hunan Provincial Education Department(07C765 07C744)
文摘Based on trajectory equations of gas bubble,an eddy-bubble interaction(EBI)model was developed. This model considered the effect of non-drag forces and took the eddy-bubble interaction time as the refreshing time scale of turbulent fluctuations.The relationship between the crossing-eddy time and the eddy lifetime was discussed,and the predicted distributions of radial,axial velocities of bubbles and gas holdup were also given. Compared with eddy lifetime(EL)model,the EBI model gives somewhat smaller axial velocity in the upper circulation region and larger velocity in the lower circulation region,causing that fewer bubbles reach the lower circulation region and gas holdup becomes higher in the upper circulation region.The predicted gas holdup by the EBI model approaches closer to the experimental data in the discharge stream region.
文摘Blistering cupping therapy, as a new type of cupping therapy, has attracted more and more attention of clinical doctor and scholars in home and abroad. Blistering cupping therapy achieves better effects through the formation of blistering fluid after suction. However, it is still controversial whether cupping induced blisters are beneficial to recovery of diseases, and the mechanism is still not completely clear. Here on the basis of the traditional cupping method, we aimed to identify the mechanism of blistering cupping from the levels of biomechanics and molecular biology. The negative pressure attraction induced by cupping suck should be of value in increasing pain threshold and relieving pain as well as improving the blood circulation and metabolism. Furthermore, the blistering fluid induced by cupping was the inflammatory substance actually that discharged through the superficial lymphatic vessels, including immunoglobulin, lysozyme, erythrocytes, etc. which could cause the autogenetic inflammatory reaction of selected cupping area, and further activated certain immune pathways including anti-oxidation, anti-apoptosis, tissue repairing and metabolic regulation. Besides, the formation of scar induced by blistering cupping was not only the result of excessive inflammatory response, but also involved in mobilizing the immune response.