In order to elaborate the app licability of osl to loess , especially single aliquot regenerative protocol ( sar ) , involving stimulation of the same disc with an infra - red laser diode followed by blue leds to polymineralic fine - grains of loess , such explanations as light bleaching , preheat , anomalous fading , prior - ir exposure were investigated in this paper . for drawing adequate coarse grains from loess , quartz and feldspars , as well as loess , were etched by hydrofluoric acid and fluorosilicic acid . the sequence of ages of holocene loess in weihe rivier basin has been established by single - aliquot ( sar ) and multiple - aliquot using fine - grains and sar using coarse - grains 本文通过渭河流域全新世黄土的光晒退实验，地表黄土样品的d _ e值测定，细颗粒单片的预热、反常衰退、红外暴露实验，说明释光测年在全新世黄土中应用的可行性及单片再生剂量法( sar )在黄土细颗粒中的适用性；为了从黄土中分离出足够的粗颗粒，进行了纯石英和长石的氢氟酸( hf )和氟硅酸( h _ 2sif _ 6 )溶蚀实验，黄土粗颗粒石英溶蚀分离实验；通过细颗粒单片、多片的blsl 、 irsl和post - irosl ，热释光，及粗颗粒石英的blsl的年代测定，选择适于全新世黄土的释光测年方法，并建立了渭河流域全新世黄土的年代序列。
Then , using the large - scale coarse grained soil test system , the relative density and direct shear characteristics of sand - gravel mixtures in different size distribution were tested . and the soc affecting mechanism derived from non - uniform granular material was discussed . the phenomenon can be observed that , along with the increase of non - uniform degree , the accumulate structure will become more complex , and the sliding resistance among sands will grow accordingly 在此基础上，利用大型粗颗粒实验系统，测定不同非均匀系数沙石材料的相对密度和直剪特性，探讨了颗粒非均匀程度对自组织临界性影响的具体物理力学机制：随着非均匀度的增大，散粒堆积体的颗粒结构空间分布堆积方式的多样性增大，颗粒滑动的摩擦耗能增加。
