很短的距离

First, the speed of the reaction between mud acid and rock is very fast, the effective distance of acid is short, active acid can not reach deep formation.

首先，高温下常规土酸与地层矿物反应速度极快，酸液有效作用距离短，活性酸不能到达地层深部；其次，HF与铝硅酸盐的化学反应不是简单的一次反应，其副产物氟硅酸和氟铝化物还可与铝硅酸盐发生二次反应和三次反应，形成一系列不溶性的沉淀物，对储层造成严重伤害；第三，高温情况下酸液对井下管柱及工具腐蚀性很强，对缓蚀剂性能要求高。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。