Transient Safety Analysis of Small Leaded-Bismuth Cooled Fast Reactor

Based on the multi-channel thermal model and the power model, the calculation code which could be used in the transient safety analysis of fast reactor was developed in unprotected overpower accident, unprotected loss of flow accident and unprotected loss of hot sink accident in the paper. By this code, the core reactivity, power and thermal parameter changes with time in different accident cases were calculated and the core neutronics and thermal-hydraulics performance was analyzed. The results indicate that the core design has safety features when accident happens.     

Studies on LLFP transmutation in a pressurized water reactor

A systematic study on the long-lived fission product (LLFP) transmutation in a pressurized water reactor (PWR) is performed, aiming at an optimal transmutation strategy for present nuclear energy development. The LLFPs selected in the analysis include ⁹⁹Tc and ¹²⁹I discharged from light water reactors (LWRs). The isotope ¹²⁷I is also considered to avoid the difficulties in isotopes separation. To minimize the negative impacts of LLFPs on the core performance and safety parameters, metallic technetium or MgI₂ target pins mixed with ZrH₂ are designed and investigated. Through the numerical analysis on equilibrium cycles, the transmuted amounts of ⁹⁹Tc and ¹²⁹I equal to the yields from 1.94 and 4.22 PWRs with a power of 1000 MWe, respectively. Numerical results indicate that both ⁹⁹Tc and ¹²⁹I can be transmuted conveniently in present PWRs in the form of target pins.     

Neutronics analysis of minor actinides transmutation in a fusion-driven subcritical system

The minor actinides (MAs) transmutation in a fusion-driven subcritical system is analyzed in this paper. The subcritical reactor is driven by a tokamak D-T fusion device with relatively easily achieved plasma parameters and tokamak technologies. The MAs discharged from the light water reactor (LWR) are loaded in transmutation zone. Sodium is used as the coolant. The mass percentage of the reprocessed plutonium (Pu) in the fuel is raised from 0 to 48% and stepped by 12% to determine its effect on the MAs transmutation. The lesser the Pu is loaded, the larger the MAs transmutation rate is, but the smaller the energy multiplication factor is. The neutronics analysis of two loading patterns is performed and compared. The loading pattern where the mass percentage of Pu in two regions is 15% and 32.9% respectively is conducive to the improvement of the transmutation fraction within the limits of burn-up. The final transmutation fraction of MAs can reach 17.8% after five years of irradiation. The multiple recycling is investigated. The transmutation fraction of MAs can reach about 61.8% after six times of recycling, and goes up to about 86.5% after 25.     

基于磁控形状记忆合金的伺服阀驱动器

磁控形状记忆合金(MSMA)是一种新型的具有形状记忆功能的功能材料。用这种材料制成的驱动器具有响应频响高、驱动力大、可控位移大等特点,特别适合于制造高精度大位移运动与位置控制驱动器。根据MSMA以上优点,研究基于MSMA的先导式伺服阀驱动器,设计出一种新型的驱动器结构:用弹簧恢复MSMA形变,直流绕组产生偏磁磁场,励磁绕组提供可控磁场。通过已有数据分析了材料静态特性,用MATLAB软件进行数据分析并且仿真,得到材料的驱动力及位移与时间的关系,验证了结构设计的合理性。     

基于ARM和GPRS的数据采集传输仪系统设计

文章设计了一种以ARM单片机为核心、采用GPRS作为无线传输方式的数据采集传输仪,此设备通过串口与传感器进行通信实现采集数据,然后通过GPRS模块把传感器数据发送到控制中心.文章首先介绍了ARM处理器的优点和GPRS无线传输的特点,然后重点介绍了数据采集传输仪的硬件系统,并对设计重点做了详细分析,最后对此数据采集仪的技术优势和潜在应用做了分析和展望.     

微生物及其酶法生产稀有L-戊糖

L-戊糖是高价值的稀有糖,是制备抗病毒药物的重要手性前体分子。微生物合成或者酶生物催化是生产非天然稀有单糖的富有吸引力的技术手段,本文综述了微生物及酶法合成几种稀有L-戊糖的研究进展,展望了稀有L-戊糖的市场前景。     

一种新型的移动闪光焊轨机供电系统

针对传统柴油发电机组给移动闪光焊轨机供电的不足,提出一种新型移动闪光焊轨机供电系统.通过分析移动闪光焊轨机工作特性,提出采用超级电容器与双向DC/DC功率变换器连接后通过开关与蓄电池组并联,构成蓄电池-超级电容混合储能供电系统应用于驱动移动闪光焊轨机工作.建立了其复合储能系统仿真模型并进行测试,同时通过系统样机的产品开...     

基于组态王的远程油气管线阀门监控系统

自动化监控组态软件是一个工程监控和数据采集系统。本文介绍了KingView6．5的主要功能，给出了一个利用KingView6．5实现的远程油气管线监控系统，详细阐述了系统的组成结构、软件功能，通过实例说明其开发过程。实践证明，该系统图形界面友好，可靠性高，操作方便，安全稳定，应用效果好。     

钙钛矿型复合氧化物LaFeO3纳米材料的穆斯堡尔谱研究

在室温下用Mossbauer谱研究了具有不同晶粒尺寸、不同压力下压实的纳米晶材料LaFeO_3。结果表明,70nm的常规LaFeO_3晶粒呈反铁磁性结构,12.4nm的LaFeO_3纳米晶是较弱的反铁磁结构和较强的超顺磁结构的叠加。纳米晶材料的界面/体相和超精细磁场随着压实力而改变。16nm的LaFeO_3纳米晶的所有变化均小于12.4nm的LaFeO_3纳米晶的变化。转靶XRD结果表明,经过不同压力压实的样品发生了晶粒碎化、晶间接触及位错等现象。     

涟钢30m2和40m2烧结机自动配料控制系统

介绍烧结机的配料系统采用ＰＬＣ加上位管理机来改造原有手工操作,收到了较好的效果。具体介绍自动配料控制系统的组成,ＰＬＣ和称量控制仪表的选择,系统的控制与操作,还介绍了系统软件功能及特点,系统抗干扰措施。