Size-fractionated 210Po and 210Pb, in the size fractions >0.4 μm, >2 μm and >10 μm, were examined to determine the seasonal variability of particulate fluxes in Xiamen Bay. Good correlations between 210Po ...Size-fractionated 210Po and 210Pb, in the size fractions >0.4 μm, >2 μm and >10 μm, were examined to determine the seasonal variability of particulate fluxes in Xiamen Bay. Good correlations between 210Po and particulate organic carbon (POC) or non-Particulate Organic Matter (nPOM) suggested that 210Po can be used to trace the export fluxes of POC and nPOM. Both steady-state (SS) model and nSS model were used to evaluate fluxes of size-fractionated 210Po, results showed that nSS model was better than the SS model in coastal areas. Based on the nSS model, size-fractionated POC fluxes decreased with increasing particle size. For the particle size studied, maximum POC fluxes occurred in autumn, followed by spring, winter, and summer. Fluxes of nPOM were an order of magnitude higher than the corresponding size-fractionated POC fluxes. Differences between size-fractionated nPOM fluxes indicated that hydrodynamic conditions were the main factor regulating transportation of particulate out of the inner Bay. In winter most particulates, including >10 μm particles, were transported under the strongest hydrodynamic conditions. In contrast, only a fraction of the <2 μm particulates were transported from the inner Bay in spring. This study suggested that 210Po is a powerful tracer of seasonal particulate export in coastal seas.展开更多
This paper deals mainly with pneumatic measurements on a radial turbine nozzle cascade. The fill radial cascade guarantees the exit flow field periodicity downstream of it. A special traversing mechanism with a five -...This paper deals mainly with pneumatic measurements on a radial turbine nozzle cascade. The fill radial cascade guarantees the exit flow field periodicity downstream of it. A special traversing mechanism with a five - hole conical probe moving along a circular path behind the cascade was used for flow field investigation in this type of cascade with very low aspect ratio. The analyses of results of 2D and 3D pneumatic measurements including loss coefficient values are presented.展开更多
基金Supported by the National Natural Science Foundation of china (Nos. 40576037, 40606022, 90411016)China Ocean Mineral Resources R & D Association (COMRA) Project (DYXM-115-01-3-04)
文摘Size-fractionated 210Po and 210Pb, in the size fractions >0.4 μm, >2 μm and >10 μm, were examined to determine the seasonal variability of particulate fluxes in Xiamen Bay. Good correlations between 210Po and particulate organic carbon (POC) or non-Particulate Organic Matter (nPOM) suggested that 210Po can be used to trace the export fluxes of POC and nPOM. Both steady-state (SS) model and nSS model were used to evaluate fluxes of size-fractionated 210Po, results showed that nSS model was better than the SS model in coastal areas. Based on the nSS model, size-fractionated POC fluxes decreased with increasing particle size. For the particle size studied, maximum POC fluxes occurred in autumn, followed by spring, winter, and summer. Fluxes of nPOM were an order of magnitude higher than the corresponding size-fractionated POC fluxes. Differences between size-fractionated nPOM fluxes indicated that hydrodynamic conditions were the main factor regulating transportation of particulate out of the inner Bay. In winter most particulates, including >10 μm particles, were transported under the strongest hydrodynamic conditions. In contrast, only a fraction of the <2 μm particulates were transported from the inner Bay in spring. This study suggested that 210Po is a powerful tracer of seasonal particulate export in coastal seas.
基金supported by the Project KONTAKT #ME 08025 monitored by the Ministry of Education of the Czech Republicthe grant No101/08/0623 supported by the Czech Science Foundation
文摘This paper deals mainly with pneumatic measurements on a radial turbine nozzle cascade. The fill radial cascade guarantees the exit flow field periodicity downstream of it. A special traversing mechanism with a five - hole conical probe moving along a circular path behind the cascade was used for flow field investigation in this type of cascade with very low aspect ratio. The analyses of results of 2D and 3D pneumatic measurements including loss coefficient values are presented.
