Based on the concept of the open set relative to a subbase for the topology,this paper defines the locally connectedness relative to a subbase and the locally Path connectedness relative to a subbase,and obtain their basic properties,which genera-lize locally connectedness in a general topology.

The definitions of interior and closure of a set about a subbase for a topological space are introduced in this paper,and then some properties of them are discussed;the agreeable condition of the topology determined by the closure operation,interior operation and subsetfamily is gained.

The interior and the closure of a subset relative to a subbase for the topology are introduced to study the relationships between the rough sets and the topological space.

Under the natural ecological condition of rape field cultivation,effect on rape soil and dissolution in the base ions of K,Na,Ca and Mg with different pH of simulated acid rain was investigated by spraying and soil columns leaching experiments.

Significant correlation between the total amount of four kinds of base ions in the leacheate and concentration of H + of acid rain is evident.

The effects of simulated acid rain on releasing base cations of red soil were studied with leaching experiments.

The results showed that amounts of leaching base cations increased obviously when the pH value of simulated acidic rain was lower than 3.

The releasing characteristics and mechanism of base ions in four types of typical soils(yellow soil,grey-brown purplish soil,red-brown purplish soil,red purplish soil),which were collected from the Three Gorges Reservior Region,are studied by simulated acid rain leaching of soil columns equipment indoor.

Effect of ionic groups on the surface and the interfacial adhesion properties of poly(p-phenylene benzoxazole) (PBO) fiber;