The numerical simulation and physical experiments indicate that the motion of sediment clouds can be divided into three stages: accelerating-falling, separating-diffusion and horizontal-spreading. There are marked differences of the clouds area, concentration change and moving velocity of front between each stage.
On the basis of researched documents,the paper has concluded the major factors of expansion of city-size that they are national and foreign investments and hierarchy of cities by means of regression analysis.
On the basis of researched documents, concluded that the major factors of expansion of city-size are national and foreign investments and hierarchy of cities by means of regression analysis.
(3) An ideal dominant species in the early successional stage were annuals with stable seed pool, CR_life strategy, S_regeneration strategy, and strong competitive ability on relatively poor soil, while perennials capable of intensive lateral spread and colonal ability, requiring high nutrient supply, and having C_life strategy would be the dominant species in the subsequent stages.
The extended dendritic arbor of APCs and ILNs (dorsal spread up to 10-20 μm below surface, horizontal spread up to 1100-1500 μm) enables these cells to sample visual information from a wide area of the visual field.
The rate of local recurrences was related to the horizontal spread of the tumor (insular/circular, largest tumor diameter), to the macroscopic pattern of growth, and to the Dukes classification.
Although further studies are needed to evaluate the role of these genes in the horizontal-spreading defective phenotype, our data clearly indicate that mutations in these genes do not affect the oncogenicity of MDV.
In the paddy field, the mycelial development of Pellicularia sasakii (Shirai) Wei on the rice plant was closely related to a number of factors especially to the growth stage of the plant and the prevailing climatic condition. Generally, the mycelium developed very scanty before the pregnancy period. Henceforth, the mycelial development was greatly accelerated. The deveIopment reached a maximum at about 10 days before or after the heading. For the early rice varieties the mycelial development ceased at the r...
On the basis of crustal structure,focal mechanism,seismicity and geophysical research,the authors suggest that in North China exists gravitational lateral spreading of the crustal substances mainly from SW to NE.In this paper,fundamental characteristics of such a mass spreading as well as its relation to recent tectonic motion and seismic activity are presented.It is shown that gravity is to contribute to recent tectonic motion and seismic activity in this area.
The fatigue crack propagation in steel 16Mn under various heattreatmentconditions has been studied in this paper. The threshold value △A_(th) andthe requirement of mechanics for the transition from stage Ⅱ_a to Ⅱ_bin fatigue crack propagation has been analysed in view of plasticdeformation constraint, ferrite grain size and microscopic fracture me-chanism. The significance of fatigue crack propagation parameters inengineering application has also been discussed. It has been identifiedthat the threshold valu...