Abstract: A housing structure for an optical module includes a housing and a heat dissipation component. The heat dissipation component includes a heat dissipation bottom plate and heat dissipation fins thereon. The housing structure has two opposing air guide ports, and the heat dissipation component is inside the housing. The heat dissipation fins are between the two air guide ports, and adjacent heat dissipation fins form a heat dissipation channel. Guide channels are between the heat dissipation channel and the air guide ports, and connect the heat dissipation channel to the air guide ports. This housing structure facilitates heat dissipation and inhibits solder paste to overflow through the air guide, thus avoiding contamination of the housing. The solder paste remains inside the housing, and does not affect the measurement accuracy or real-time monitoring function of temperature sensors on the housing.

Abstract: A gray control rod having a neutron absorber comprising terbium and dysprosium is provided. The neutron absorber comprises at least one first component and at least one second component, the reactivity worth of the first component increases as the service time of the neutron absorber increases, the reactivity worth of the second component decreases as the service time of the neutron absorber increases; the reactivity worth of the neutron absorber varying no more than 15% within the service time of the neutron absorber. By using the first component and the second component to form the neutron absorber, and adjusting the proportion of the respective components in the neutron absorber, the neutron absorber having a substantially planar reactivity worth loss characteristic can be obtained. The gray control rod and the assembly having required reactivity controlling ability can be obtained by increasing or decreasing the material dosage of the neutron absorber.

Abstract: A heat pipe based passive residual heat removal system for a spent fuel pool (3). Partitions (6) are arranged around an inside of the spent fuel pool. Evaporation-end heat pipes (4) are arranged between the outside of the partitions and an inner wail of the pool. The evaporation-end heat pipes have outlets that extend beyond the pool and are connected to an Inlet of an ascending pipe (10), and have inlets connected to an outlet of a descending pipe (5). Condensation-end heat pipes (7) have inlets connected to an outlet of the ascending pipe, and have outlets connected to an inlet of the descending pipe. The heat pipes cool the spent fuel pool. A heat exchange by phase change of working medium in the heat pipe leads to heat exchange of low temperature difference and high efficiency, relying on density difference for natural circulation drive.

Abstract: A gray control rod, a neutron absorber thereof and a gray control rod assembly. The neutron absorber comprises at least one first component and at least one second component, the reactivity worth of the first component increases as the service time of the neutron absorber increases, the reactivity worth of the second component decreases as the service time of the neutron absorber increases; the reactivity worth of the neutron absorber varying no more than 15% within the service time of the neutron absorber. By using the first component and the second component to form the neutron absorber, and adjusting the proportion of the respective components in the neutron absorber, the neutron absorber having a substantially planar reactivity worth loss characteristic can be obtained. The gray control rod and the assembly having required reactivity controlling ability can be obtained by increasing or decreasing the material dosage of the neutron absorber.

Abstract: A heat pipe based passive residual heat removal system for a spent fuel pool has a plurality of partitions (6) arranged around the inside of a spent fuel pool (3), wherein the heights of the partitions (6) are all lower than the height of the spent fuel pool (3); a plurality of evaporation-end heat pipes (4) are arranged between the outside of the partitions (6) and an inner wall of the spent fuel pool (3), and these evaporation-end heat pipes (4) are divided into several groups. Top outlets of each group of evaporation-end heat pipes (4) are extended beyond the spent fuel pool (3) and are connected to an inlet of an ascending pipe (10). An outlet of the ascending pipe (10) is connected to top inlets of a group of condensation-end heat pipes (7) comprising a plurality of condensation-end heat pipes. Bottom outlets of the group of condensation-end heat pipes (7) are connected to an inlet of a descending pipe (5).