The impact of initial guess and grid resolutions on the analysis and prediction has been investigated over the Indian region. For this purpose, an univariate objective analysis scheme and a primitive equation barotrop...The impact of initial guess and grid resolutions on the analysis and prediction has been investigated over the Indian region. For this purpose, an univariate objective analysis scheme and a primitive equation barotropic model have been used. The impact of initial guess and the resolutions on analysis and prediction is discussed.展开更多
In order to probe the mechanism of the phenomena of seismic electromagnetic radiation (EMR), we have completed field experiment on EMR caused by explosiom of rocks. In the experiments, the data of medium lo...In order to probe the mechanism of the phenomena of seismic electromagnetic radiation (EMR), we have completed field experiment on EMR caused by explosiom of rocks. In the experiments, the data of medium low freguency (<5000 Hz) EMR caused by 26 explosion tests of small dimension rocks have been obtained. This paper shows some representative observational results of the field experiment. The observational results show that, nearly 20 points of the 26 explosive points, the EMR phenomena are recorded at various degrees in the related explosive processes. The EMR intensities decay with the distance from explosive origins and increase with the explosive energy. The EMR records have certain repeatability (under the same condition), complexity( multiple EMR effects caused by one explosion) and regional characteristics such as rock structure and observational direction etc.展开更多
Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the ...Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the 11th Five-Year Plan, to build the resource-conservation and environment-friendly society during the 11th Five-Year Plan period (2006-2010), it is crucial to implement the policy of "Large (units) In and Small (units) Out (LISO)" (i.e., replacing small units with large ones) and accelerate the retirement of small thermal units. According to the statistics, the power industry has made a significant progress in SO2 emission reduction during the first half of 2007. Specifically, with 18.3% growth in power generation, the SO2 emission was reduced by 5.2% compared with the same period in 2006. By the end of July 2007, the retired small units have totaled 6950 MW, 85% of which belongs to the five major power generation groups such as Guodian and Huadian. In this article, the achievements and remaining issues in Henan, Jiangsu, Sichuan Power Companies and East China Grid Company were presented and discussed thoroughly.展开更多
Twenty-four New Zealand white rabbits were plated on their intact left tibiae with stainless steel plates and 4 animals served as controls. The plates were removed 2 months after implantation in 20 plated animals. Of ...Twenty-four New Zealand white rabbits were plated on their intact left tibiae with stainless steel plates and 4 animals served as controls. The plates were removed 2 months after implantation in 20 plated animals. Of them, 4 were sacrificed immediately after plate removal and the other 16 were killed in successive groups with 4 in each group 1,2,3 and 4 months after plate removal respectively. The remaining 4 plated animals were killed at 6 months after implantation. Bone samples under the plates were harvested and prepared for polarized light microscopy to investigate the repair of the regional osteoporosis induced by rigid implant. The results indicated that the regional osteoporosis could recover gradually after plate removal. The repair process manifested itself mainly as the repair of resorption cavities and the remodeling of collagen fibers. The orientation of the collagen fibers remained disorganized when the resorption cavities had been repaired. It is suggested that delayed restoration of bone structure might be one of the potential causes of refracture after removal of the rigid implant.展开更多
In this study, we employ two regional climate models(RCMs or RegCMs), which are RegCM4 and PRECIS(Providing Regional Climates for Impact Studies), with a horizontal grid spacing of 25 km, to simulate the precipitation...In this study, we employ two regional climate models(RCMs or RegCMs), which are RegCM4 and PRECIS(Providing Regional Climates for Impact Studies), with a horizontal grid spacing of 25 km, to simulate the precipitation dynamics across China for the baseline climate of 1981–2010 and two future climates of 2031–2060 and 2061–2090. The global climate model(GCM)—Hadley Centre Global Environment Model version 2-Earth Systems(HadGEM2-ES) is used to drive the two RCMs. The results of baseline simulations show that the two RCMs can correct the obvious underestimation of light rain below 5 mm day^-1 and the overestimation of precipitation above 5 mm day^-1 in Northwest China and the Qinghai–Tibetan Plateau, as being produced by the driving GCM. While PRECIS outperforms RegCM4 in simulating annual precipitation and wet days in several sub-regions of Northwest China, its underperformance shows up in eastern China. For extreme precipitation, the two RCMs provide a more accurate simulation of continuous wet days(CWD) with reduced biases and more realistic spatial patterns compared to their driving GCM. For other extreme precipitation indices, the RCM simulations show limited benefit except for an improved performance in some localized regions. The future projections of the two RCMs show an increase in the annual precipitation amount and the intensity of extreme precipitation events in most regions. Most areas of Southeast China will experience fewer number of wet days, especially in summer, but more precipitation per wet day(≥ 30 mm day^-1). By contrast, number of wet days will increase in the Qinghai–Tibetan Plateau and some areas of northern China. The increase in both the maximum precipitation for five consecutive days and the regional extreme precipitation will lead to a higher risk of increased flooding. The findings of this study can facilitate the efforts of climate service institutions and government agencies to improve climate services and to make climate-smart decisions.展开更多
To study the influence of back feeding particles on gas-solid flow in the riser, this paper investigated the flow asymmetry in the solid entrance region of a fluidized bed by particle concentration/velocity measuremen...To study the influence of back feeding particles on gas-solid flow in the riser, this paper investigated the flow asymmetry in the solid entrance region of a fluidized bed by particle concentration/velocity measurements in a cold square circulating fluidized beds (CFB). The pressure drop distribution along the riser and the saturation carrying capacity of gas for Geldart-B type particles were first analyzed. Under the condition of u0 = 4 m/s and Gs = 21 kg/(m^2 s), the back feeding particles were found to penetrate the lean gas-solid flow near the entrance (rear) wall before reaching the opposite (front) wall, thus leading to a relatively denser region near the front wall in the bottom bed. Higher solid circulation rate (u0 =4 m/s, Gs = 33 kg/(m^2 s)) resulted in a higher particle concentration in the riser. However the back feeding particles with higher momentum increased the asymmetry of the particle concentration/velocity profile in the solid entrance region. Lower air velocity (u0 =3.2 m/s) and Gs =21 kg/(m2 s), beyond the saturation carrying capacity of gas, induced an S-shaped axial solid distribution with a denser bottom zone. This limited the penetration of the back feeding particles and forced the flnidizing air to flow in the central region, thus leading to a higher solid holdup near the rear wall. Under the conditions of uo = 4 m/s and Gs = 21 kg/(m^2 s), addition of coarse particles (dp= 1145 μm) into the bed made the radial distribution of solids more symmetrical.展开更多
文摘The impact of initial guess and grid resolutions on the analysis and prediction has been investigated over the Indian region. For this purpose, an univariate objective analysis scheme and a primitive equation barotropic model have been used. The impact of initial guess and the resolutions on analysis and prediction is discussed.
文摘In order to probe the mechanism of the phenomena of seismic electromagnetic radiation (EMR), we have completed field experiment on EMR caused by explosiom of rocks. In the experiments, the data of medium low freguency (<5000 Hz) EMR caused by 26 explosion tests of small dimension rocks have been obtained. This paper shows some representative observational results of the field experiment. The observational results show that, nearly 20 points of the 26 explosive points, the EMR phenomena are recorded at various degrees in the related explosive processes. The EMR intensities decay with the distance from explosive origins and increase with the explosive energy. The EMR records have certain repeatability (under the same condition), complexity( multiple EMR effects caused by one explosion) and regional characteristics such as rock structure and observational direction etc.
文摘Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the 11th Five-Year Plan, to build the resource-conservation and environment-friendly society during the 11th Five-Year Plan period (2006-2010), it is crucial to implement the policy of "Large (units) In and Small (units) Out (LISO)" (i.e., replacing small units with large ones) and accelerate the retirement of small thermal units. According to the statistics, the power industry has made a significant progress in SO2 emission reduction during the first half of 2007. Specifically, with 18.3% growth in power generation, the SO2 emission was reduced by 5.2% compared with the same period in 2006. By the end of July 2007, the retired small units have totaled 6950 MW, 85% of which belongs to the five major power generation groups such as Guodian and Huadian. In this article, the achievements and remaining issues in Henan, Jiangsu, Sichuan Power Companies and East China Grid Company were presented and discussed thoroughly.
文摘Twenty-four New Zealand white rabbits were plated on their intact left tibiae with stainless steel plates and 4 animals served as controls. The plates were removed 2 months after implantation in 20 plated animals. Of them, 4 were sacrificed immediately after plate removal and the other 16 were killed in successive groups with 4 in each group 1,2,3 and 4 months after plate removal respectively. The remaining 4 plated animals were killed at 6 months after implantation. Bone samples under the plates were harvested and prepared for polarized light microscopy to investigate the repair of the regional osteoporosis induced by rigid implant. The results indicated that the regional osteoporosis could recover gradually after plate removal. The repair process manifested itself mainly as the repair of resorption cavities and the remodeling of collagen fibers. The orientation of the collagen fibers remained disorganized when the resorption cavities had been repaired. It is suggested that delayed restoration of bone structure might be one of the potential causes of refracture after removal of the rigid implant.
基金Supported by the National Key Research and Development Program of China(2018YFA0606204)National Natural Science Foundation of China(51761135024 and 41671113)+1 种基金UK–China Research and Innovation Partnership Fund through the Met Office Climate Science for Service Partnership(CSSP)China as part of the Newton Fund(P106409)Social Development Project of Science and Technology Commission of Shanghai Municipality(19DZ1201500)。
文摘In this study, we employ two regional climate models(RCMs or RegCMs), which are RegCM4 and PRECIS(Providing Regional Climates for Impact Studies), with a horizontal grid spacing of 25 km, to simulate the precipitation dynamics across China for the baseline climate of 1981–2010 and two future climates of 2031–2060 and 2061–2090. The global climate model(GCM)—Hadley Centre Global Environment Model version 2-Earth Systems(HadGEM2-ES) is used to drive the two RCMs. The results of baseline simulations show that the two RCMs can correct the obvious underestimation of light rain below 5 mm day^-1 and the overestimation of precipitation above 5 mm day^-1 in Northwest China and the Qinghai–Tibetan Plateau, as being produced by the driving GCM. While PRECIS outperforms RegCM4 in simulating annual precipitation and wet days in several sub-regions of Northwest China, its underperformance shows up in eastern China. For extreme precipitation, the two RCMs provide a more accurate simulation of continuous wet days(CWD) with reduced biases and more realistic spatial patterns compared to their driving GCM. For other extreme precipitation indices, the RCM simulations show limited benefit except for an improved performance in some localized regions. The future projections of the two RCMs show an increase in the annual precipitation amount and the intensity of extreme precipitation events in most regions. Most areas of Southeast China will experience fewer number of wet days, especially in summer, but more precipitation per wet day(≥ 30 mm day^-1). By contrast, number of wet days will increase in the Qinghai–Tibetan Plateau and some areas of northern China. The increase in both the maximum precipitation for five consecutive days and the regional extreme precipitation will lead to a higher risk of increased flooding. The findings of this study can facilitate the efforts of climate service institutions and government agencies to improve climate services and to make climate-smart decisions.
基金supported financially by the Ministry of Science of China under the National Key Technology R&D Program of China (Contract No.:2006BAA03B01-07)
文摘To study the influence of back feeding particles on gas-solid flow in the riser, this paper investigated the flow asymmetry in the solid entrance region of a fluidized bed by particle concentration/velocity measurements in a cold square circulating fluidized beds (CFB). The pressure drop distribution along the riser and the saturation carrying capacity of gas for Geldart-B type particles were first analyzed. Under the condition of u0 = 4 m/s and Gs = 21 kg/(m^2 s), the back feeding particles were found to penetrate the lean gas-solid flow near the entrance (rear) wall before reaching the opposite (front) wall, thus leading to a relatively denser region near the front wall in the bottom bed. Higher solid circulation rate (u0 =4 m/s, Gs = 33 kg/(m^2 s)) resulted in a higher particle concentration in the riser. However the back feeding particles with higher momentum increased the asymmetry of the particle concentration/velocity profile in the solid entrance region. Lower air velocity (u0 =3.2 m/s) and Gs =21 kg/(m2 s), beyond the saturation carrying capacity of gas, induced an S-shaped axial solid distribution with a denser bottom zone. This limited the penetration of the back feeding particles and forced the flnidizing air to flow in the central region, thus leading to a higher solid holdup near the rear wall. Under the conditions of uo = 4 m/s and Gs = 21 kg/(m^2 s), addition of coarse particles (dp= 1145 μm) into the bed made the radial distribution of solids more symmetrical.