全预应力混凝土板长期挠度的计算

文本考虑了混凝士收缩、蠕变和钢筋松弛的相互影响,用拟协调元法进行预应力混凝土双向板的挠度计算,编制成电算程序,并给出了算例。     

Thermal analysis of the CSNS H－ ion source

There are two cooling systems to maintain the thermal stability of the CSNS H^- ion source during its operation： Air-cooling in the source body of the discharging chamber and water-cooling in the flange on which the discharging chamber is installed. The optimal cooling parameters to ensure the operation of the H^- ion source are determined through a thermal analysis. In addition, a transient analysis is also performed to know exactly the transient temperature variation during the whole 40 ms period of the pulsed mode operation of the ion source.     

Introduction to the overall physics design of CSNS accelerators

The China Spallation Neutron Source (CSNS) is an accelerator-based facility. The     

电动桥式起重机负载升降过程的系统动力学模拟

从系统的角度考虑电动桥式起重机起升机构工作过程中的动力学模拟问题。首先,由系统的拉格朗日函数、约束条件和电机的磁共能定义修正的拉格朗日函数;随后,应用Hamilton原理和三相感应电机瞬态模型得出起升机构工作过程中电动桥式起重机系统的运动方程。为验证模型的效果,本文还进行了转子串电阻速度控制系统控制下的32t电动桥式起重机吊运额定负载下降过程的数值模拟,分析了高速浮动轴扭转刚度以及制动过程中转子电阻的配置方案对系统动力响应的影响。模拟结果表明,制动过程中起升机构高速浮动轴所受载荷远大于起动过程中所受载荷,制动开始时在电机转子电路中增加一级较大的外串电阻有利于减小下降制动阶段系统中的动载。     

超导质子直线加速器的分段研究

对超导直线加速器的分段进行了详细的研究.包括超导加速器的分段原则的讨论,对称性分段和非对称性分段的讨论.超导加速腔的加速单元数及设计值β_G的确定,加速器的能量增益的确定.     

Design and development of the CSNS ion source control system

Now that the CSNS ion source test stand has been stably working for years, an online control system for the CSNS ion source which aims to be more stable and reliable is now under development. F3RP61-2L, a new PLC CPU module running an embedded Linux system, is introduced to the system as an IOC, to function together with the I/O modules of FA-M3 PLC on the PLC-bus. The adoption of the new IOC not only simplifies the architecture of the control system, but also improves the data transmission speed. In this paper, the design and development of the supervisory and control system for the CSNS ion source are described.     

测定饲料中喹乙醇含量的反相高效液相色谱法

建立了高效液相色谱法测定饲料中喹乙醇含量的方法 ;饲料用甲醇 -水提取 ,在380nm波长下检测 ,色谱柱为NOVA_PakC18(3.9mm×150mm ,4μm) ,流动相为甲醇 -水 (体积比为10∶90) ,流速为1.0mL/min ,喹乙醇质量浓度在2.5～20.0mg/L范围内与峰面积呈良好线性关系 ,相对标准偏差为1.2 %～1.6 % ,回收率为97 %～101%。     

固相萃取/超高效液相色谱-串联质谱测定水果中5种植物生长调节剂残留量

建立了固相萃取/超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定水果中6-苄基腺嘌呤(6-BA)、噻苯隆、氯吡脲、多效唑和烯效唑5种植物生长调节剂残留量的分析方法。水果样品经乙腈提取,NH2固相萃取小柱进行富集、净化,以二氯甲烷-甲醇(92∶8)为洗脱溶液,浓缩定容后,用Waters ACQUITY UPLC BEH C18(50 mm×2.1 mm,1.7μm)色谱柱分离,流速0.3 m L/min,以水-甲醇为流动相梯度洗脱,于UPLC-MS/MS仪多反应监测(MRM)模式测定,基质匹配标准溶液外标法定量。结果表明,5种植物生长调节剂在5~500 ng/m L浓度范围内呈良好的线性关系,相关系数(r2)为0.996 1~0.999 6。在0.004,0.02,0.1 mg/kg加标水平下,方法的回收率为75.6%~110.5%,相对标准偏差(RSD)为1.2%~12.8%,方法检出限(LOD,S/N≥3)为0.001~0.002 mg/kg,定量下限(LOQ,S/N≥10)为0.003~0.006 mg/kg。该方法操作简便、灵敏度高、准确可靠,适用于水果中5种植物生长调节剂残留量的同时测定。