The job of a manager is the constant concentration.

一个管理者要做的就是时刻保持注意力集中。

The paper introduces a automatically controlling method which is able to maintain constant concentration of the pulp discharged from a concentrator through example.

根据具体事例，介绍了一种能使普通浓密机的排矿浓度保持恒定的自动控制方法。

So this is where the concentration of B is roughly constant over time.

那么这是B的浓度，粗略地随时间变化保持常量。

In response to the appearance of such variants in the cell population the concentration of the toxic chemical in the growth medium is increased, thus keeping the selection pressure constant.

为应对细胞污染中出现的变异，有毒物质的浓度是逐步增加的，以此保证筛选力度的稳定。

In other words, the concentration of at any time is given by the initial concentration, t minus the rate constant times time.

换句话说，任意时刻A物质的浓度等于初始浓度，减去常数乘以时间。