A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger ...A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger diameter cylindrical structure, a set of values is derived also for the critical stability indices of the large diameter cylinder sunken to the sandy seabed.展开更多
Spray cooling is an effective tool to dissipate high heat fluxes from hot surfaces. This paper thoroughly investigates the effects of spray parameters on the cooling time and cooling rate under varying inlet pressure ...Spray cooling is an effective tool to dissipate high heat fluxes from hot surfaces. This paper thoroughly investigates the effects of spray parameters on the cooling time and cooling rate under varying inlet pressure using water as the coolant. Cylindrical samples of stainless steel with constant diameter, D = 25 mm, and thickness δ: 8.5 mm, 13 mm, 17.5 mm and 22 mm were investigated. Critical droplet diameter to achieve an ultrafast cooling rate of 300°C/s was estimated by using analytical model for samples of varying thickness. At an inlet pressure of 0.8 MPa, maximum cooling rates of 424.2°C/s, 502.81°C/s and 573.1°C/s were achieved for wall super heat ΔT = 600°C, 700°C and 800°C respectively.展开更多
The effect of (Pt-loaded)TiO2 crystallite diameter (i.e. Scherrer size) on the photocatalytic water splitting rate was investigated. (Pt-loaded)TiO2 powders with a wide range of crystallite diameters from about 16 to ...The effect of (Pt-loaded)TiO2 crystallite diameter (i.e. Scherrer size) on the photocatalytic water splitting rate was investigated. (Pt-loaded)TiO2 powders with a wide range of crystallite diameters from about 16 to 45 nm with a blank region between about 23 and 41 nm were prepared by various annealing processes from an identical TiO2 powder. Water splitting experiments with these powders were carried out with methanol as an oxidizing sacrificial agent. It was found that the photocatalytic water splitting rate was sensitively affected by the crystallite diameter of the (Pt-loaded)TiO2 powder. More concretely, similar steep improvements of photocatalytic water splitting rates from around 15 and a little over 2 to about 30 μmol·m-2hr-1?were obtained in the two (Pt-loaded)TiO2 crystallite diameters ranging from 16 to 23 and from 41 to 45 nm, respectively.展开更多
Dipterocarps tree species are the key species in most tropical forests because of their economic and ecological value in nature. The present study was carried out to determine the population structure and spatial patt...Dipterocarps tree species are the key species in most tropical forests because of their economic and ecological value in nature. The present study was carried out to determine the population structure and spatial pattern distribution of critically endangered dipterocarps trees in Mt. Malindang. A total of 638 individuals belonging to 86 species among the 62 genera were recorded at all sites. The highest diversity index was recorded in the elevation range of 700 - 900 masl (3.53). Dipterocarpaceae family had the highest importance value (157.66) among the families recorded in this study. Seven dipterocarp tree species were recorded in this study. Shorea negrosensis Foxw, Shorea polysperma (Blanco) Merr., and Shorea contorta S.Vidal, Shorea squamata (Turcz.) Benth. & Hook.f. ex DC. are listed as critically endangered and Dipterocarpus grandiflorus (Blanco) Blanco as Vulnerable. Soil moisture has a great influence on Anisoptera thurifera (Blanco) Blume, whereas light is positively correlated with Shorea polysperma and negatively correlated with elevation. Diameter-class distribution of critically endangered dipterocarps tree species showed an interrupted growth pattern and because a fewer number of seedlings or saplings were found in each species, this suggested that regeneration is not good. However, threats and disturbances such as illegal poaching, slash and burn, roads, and land conversion to agricultural crops and settlements contribute to the declining population of critically endangered dipterocarps species. Thus, conservation, protection and prioritization management activities in Mt. Malindang are needed.展开更多
目的:分析超声在重症患者不同部位下下腔静脉内径及塌陷指数中的应用价值。方法:选取2022年1月—2023年1月入住上饶市人民医院重症监护室(Intensive Care Unit,ICU)45例患者,超声监测患者剑突下及右侧腹腋中线图像,测量患者不同部位下...目的:分析超声在重症患者不同部位下下腔静脉内径及塌陷指数中的应用价值。方法:选取2022年1月—2023年1月入住上饶市人民医院重症监护室(Intensive Care Unit,ICU)45例患者,超声监测患者剑突下及右侧腹腋中线图像,测量患者不同部位下随着不同呼吸周期时下腔静脉内径,并计算下腔静脉塌陷指数(inferior vena cava collapsibility index,IVC-CI),分析其是否具有统计学上的相关性。结果:本研究共45例患者同时获得剑突下及右侧腹腋中线图像;吸气末、呼气末右侧腹腋中线位置的下腔静脉内径值均显著高于剑突下位置的下腔静脉内径值,差异均有统计学意义(P<0.05);吸气末与呼气末下剑突下及右侧腹腋中线位置的下腔静脉长径、下腔静脉短径、IVC-CI比较差异均无统计学意义(P>0.05);吸气末与呼气末状态下,剑突下下腔静脉长径、下腔静脉短径、IVC-CI与右侧腹腋中线位置的下腔静脉长径、下腔静脉短径、IVC-CI均显著正相关(P<0.05)。结论:不同呼吸状态下,不同部位下腔静脉长径、下腔静脉短径、IVC-CI具有良好的相关性,可互相替代测量,值得临床重视。展开更多
文摘A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger diameter cylindrical structure, a set of values is derived also for the critical stability indices of the large diameter cylinder sunken to the sandy seabed.
文摘Spray cooling is an effective tool to dissipate high heat fluxes from hot surfaces. This paper thoroughly investigates the effects of spray parameters on the cooling time and cooling rate under varying inlet pressure using water as the coolant. Cylindrical samples of stainless steel with constant diameter, D = 25 mm, and thickness δ: 8.5 mm, 13 mm, 17.5 mm and 22 mm were investigated. Critical droplet diameter to achieve an ultrafast cooling rate of 300°C/s was estimated by using analytical model for samples of varying thickness. At an inlet pressure of 0.8 MPa, maximum cooling rates of 424.2°C/s, 502.81°C/s and 573.1°C/s were achieved for wall super heat ΔT = 600°C, 700°C and 800°C respectively.
文摘The effect of (Pt-loaded)TiO2 crystallite diameter (i.e. Scherrer size) on the photocatalytic water splitting rate was investigated. (Pt-loaded)TiO2 powders with a wide range of crystallite diameters from about 16 to 45 nm with a blank region between about 23 and 41 nm were prepared by various annealing processes from an identical TiO2 powder. Water splitting experiments with these powders were carried out with methanol as an oxidizing sacrificial agent. It was found that the photocatalytic water splitting rate was sensitively affected by the crystallite diameter of the (Pt-loaded)TiO2 powder. More concretely, similar steep improvements of photocatalytic water splitting rates from around 15 and a little over 2 to about 30 μmol·m-2hr-1?were obtained in the two (Pt-loaded)TiO2 crystallite diameters ranging from 16 to 23 and from 41 to 45 nm, respectively.
文摘Dipterocarps tree species are the key species in most tropical forests because of their economic and ecological value in nature. The present study was carried out to determine the population structure and spatial pattern distribution of critically endangered dipterocarps trees in Mt. Malindang. A total of 638 individuals belonging to 86 species among the 62 genera were recorded at all sites. The highest diversity index was recorded in the elevation range of 700 - 900 masl (3.53). Dipterocarpaceae family had the highest importance value (157.66) among the families recorded in this study. Seven dipterocarp tree species were recorded in this study. Shorea negrosensis Foxw, Shorea polysperma (Blanco) Merr., and Shorea contorta S.Vidal, Shorea squamata (Turcz.) Benth. & Hook.f. ex DC. are listed as critically endangered and Dipterocarpus grandiflorus (Blanco) Blanco as Vulnerable. Soil moisture has a great influence on Anisoptera thurifera (Blanco) Blume, whereas light is positively correlated with Shorea polysperma and negatively correlated with elevation. Diameter-class distribution of critically endangered dipterocarps tree species showed an interrupted growth pattern and because a fewer number of seedlings or saplings were found in each species, this suggested that regeneration is not good. However, threats and disturbances such as illegal poaching, slash and burn, roads, and land conversion to agricultural crops and settlements contribute to the declining population of critically endangered dipterocarps species. Thus, conservation, protection and prioritization management activities in Mt. Malindang are needed.