The deterioration of a deep shaft insert at the Xing'an Coal Mine was analyzed by studying the physical and mechanical properties of the rock located at key positions relative to the shaft. Factors that influence ...The deterioration of a deep shaft insert at the Xing'an Coal Mine was analyzed by studying the physical and mechanical properties of the rock located at key positions relative to the shaft. Factors that influence shaft stability were obtained. The numerical simulation program FLAC3D was used to simulate the destruction of the deep shaft insert. Two different support methods were analyzed by simulation. The simulations demonstrate that a single stiffness support is inappropriate for this shaft insert. The appropriate support method is an integrated coupling method of rigid and flexible supports. The flexible support is applied first and then the rigid support is second. Engineering practice in the Xing'an Coal Mine shows that this technology can effectively control deep-shaft insert deterioration. This support approach provides an important direction for future project design and construction, as well.展开更多
This study aimed to investigate the effects of different process parameters on the physical properties, in vitro dissolution rate, and short and long-term stability of diclofenac potassium（DFP） granules and capsules...This study aimed to investigate the effects of different process parameters on the physical properties, in vitro dissolution rate, and short and long-term stability of diclofenac potassium（DFP） granules and capsules. DFP granules exhibited low total amounts of impurities when prepared through the wet granulation method using a granulating solvent with a low water/ethanol ratio. The impurities of the wet DFP mass dried at 70 ℃ were higher than those dried at 50 ℃ or 60 ℃. DFP granules were stable under strong light exposure during preparation. DFP granules prepared using a granulating solvent with a 1：4 water/ethanol ratio had a relatively smaller particle size and higher angle of repose than those prepared using granulating solvents with other water/ethanol ratios. The dissolution rate of DFP capsules prepared using four different water/ethanol ratios was less than 2% after 10 min of dissolution and increased to 95% within 30 min of dissolution. The total amount of drug impurities of DFP capsules prepared using a granulating solvent with 1：4 water/ethanol ratio was considerably lower than those of DFP capsules prepared using a granulating solvent with a 1：0 water/ethanol solvent ratio. Regardless of the water/ethanol ratio, the capsules showed poor stability when exposed to high temperature（60 ℃） and strong light（4500±500 Lux） for 10 days, but were relatively stable at high humidity（92.5% RH）. The results of the long-term stability（25±2 ℃ and 60%±10% relative humidity） study showed that DFP granules were more stable than DFP capsules, and were stable for 12 months. The type of encapsulating material did not affect the 2-month stability of DFP. DFP granules are sensitive to granulating solvent and drying temperature and DFP capsules should be stored away from high temperature and strong light.展开更多
基金provided by the Major Program of the National Natural Science Foundation of China (No.50490270)the National Basic Research Program of China (No.2006CB 202200)the Innovation Term Project of the Ministry of Education of China (No.IRT0656)
文摘The deterioration of a deep shaft insert at the Xing'an Coal Mine was analyzed by studying the physical and mechanical properties of the rock located at key positions relative to the shaft. Factors that influence shaft stability were obtained. The numerical simulation program FLAC3D was used to simulate the destruction of the deep shaft insert. Two different support methods were analyzed by simulation. The simulations demonstrate that a single stiffness support is inappropriate for this shaft insert. The appropriate support method is an integrated coupling method of rigid and flexible supports. The flexible support is applied first and then the rigid support is second. Engineering practice in the Xing'an Coal Mine shows that this technology can effectively control deep-shaft insert deterioration. This support approach provides an important direction for future project design and construction, as well.
基金National Natural Science Foundation of China(Grant No.81373333,81311140267)
文摘This study aimed to investigate the effects of different process parameters on the physical properties, in vitro dissolution rate, and short and long-term stability of diclofenac potassium（DFP） granules and capsules. DFP granules exhibited low total amounts of impurities when prepared through the wet granulation method using a granulating solvent with a low water/ethanol ratio. The impurities of the wet DFP mass dried at 70 ℃ were higher than those dried at 50 ℃ or 60 ℃. DFP granules were stable under strong light exposure during preparation. DFP granules prepared using a granulating solvent with a 1：4 water/ethanol ratio had a relatively smaller particle size and higher angle of repose than those prepared using granulating solvents with other water/ethanol ratios. The dissolution rate of DFP capsules prepared using four different water/ethanol ratios was less than 2% after 10 min of dissolution and increased to 95% within 30 min of dissolution. The total amount of drug impurities of DFP capsules prepared using a granulating solvent with 1：4 water/ethanol ratio was considerably lower than those of DFP capsules prepared using a granulating solvent with a 1：0 water/ethanol solvent ratio. Regardless of the water/ethanol ratio, the capsules showed poor stability when exposed to high temperature（60 ℃） and strong light（4500±500 Lux） for 10 days, but were relatively stable at high humidity（92.5% RH）. The results of the long-term stability（25±2 ℃ and 60%±10% relative humidity） study showed that DFP granules were more stable than DFP capsules, and were stable for 12 months. The type of encapsulating material did not affect the 2-month stability of DFP. DFP granules are sensitive to granulating solvent and drying temperature and DFP capsules should be stored away from high temperature and strong light.
