the narrow bed
2.Abstract: The Qiantang Estuary with violent hydrodynamic conditions is well known for its tidal bore.The regulation of the estuary in the past,especially the progress since the founding of new China are reviewed.The principles of the regulation and planning of the Qiantang Estuary formulated in 1960s are expounded,i.e.,to narrow the river to reduce the tidal prism,and to increase the ratio of the river flow to tidal discharge.The experience of estuary regulation/reclamation is summarized,especially the engineering measures to protect the groin head and to use polder dykes as sea defense works.Finally,the effect is analyzed of the large-scale constraction/reclamation in the estuary on the tides,flooding high water level,estuary bed and the northern deep waterway in the Hangzhou Bay.
3.Abstract: In order to caluculate the movement of flow and sediment in curved,narrow and long channelshe body-fitted coordinate is introduced.By regional transformation,arbitrary physical domains may be transformed into regular computational fields.A new model of suspended transport is also developed,it can describe the exchange mechanism between suspended load and bed materials.The comprehensive model is verified by observed data at Jiulongtan in the Yangtze River.
4.Twelve narrow fractions of uranium ore sand and slime with average diameters dp= 32-460μm(35 to 600 mesh) and densities ρs = 2.58-2.63g/cm3 were fluidized at ambient temperature with water. Bed expansion relation for flui-dization was determined experimentally in the range of voidage ε = 0.530-0.957. The obtained curves for IgRe versus 1 + lgε are all nonlinear.
