return coupling

The sensitivity of the system can be further improved through coupling GRIN lens, expanding beam to increase the collecting efficiency of return light on detection arm and limiting the system bandwidth by use of bandpass filter.

通过耦合GRIN透镜和扩束增大探测臂的回光收集率，以及采用带通滤波器限制系统带宽，进一步提高了系统灵敏度。

It is equipped with asphalt return tube, anti-puffing pressure vent valve, anti-aging overhead nitrogen valve, thermometer, volumeter and output asphalt rapid discharge valve and coupling.

配备沥青溢流管、防冒液呼吸阀、防老化顶置充氮阀、温度计、容量计和输出沥青的快速卸料阀及接耦。

The study concludes that the municipal water has basic natures of coupling, integration, level variation and dynamic, and economic and technical characteristics of regional monopoly, quasi-public goods, externalities, capital-intensive investment and a long period of return.

研究认为城市水务产业具有耦合性、整体性、层次性和动态性的基本属性；具有区域垄断性、准公共物品性、外部性、资本密集和投资回收期长等技术经济特征。