low-activity meaning in English

弱放射性的

Since sunspot number is closely related to solar activities like flares and coronal mass ejection , the sun might have entered a low - activity state for a rather long period of time during these minimums
由于太阳黑子数目与如耀斑和日冕抛射等太阳活动关系密切，在上述太阳黑子极小期内，太阳的活动可能沉寂了一段长时间。
An experiment to evaluate the activity value of fly - ash used as a material for highway base course is also put forward , which can be adapted easily in highway engineering . based on field road investigation sa well as above results , all behaviors of low - activity fly - ash as highway semi - rigid base course material are tested , and the strength forming principles of lime - flyash mixtures are studied by means of dta , x - ray and sem analysis
在此基础上，通过大量室内试验结合试验路的研究，测定了低活性粉煤灰在半刚性基层中的各种路用性能；最后通过差热分析、 x一射线衍射分析及电镜微观结构分析就二灰混合料的强度形成原理进行了论述。