流动注射化学发光法测定丁香酚

发现丁香酚对鲁米诺 二甲亚砜 氢氧化钠化学发光体系的抑制作用 ,在此基础上首次建立了测定丁香酚的化学发光分析法。该法灵敏度高、线性范围宽、操作简单 ,测定丁香酚的线性范围为 5× 10 -9～ 1× 10 -6g/mL ,检出限为 2 .97× 10 -9g/mL (S/N =3) ,对 5× 10 -7g/mL的丁香酚标准溶液进行 11次平行测定 ,相对标准偏差 (RSD)为 1.6 3%。该法用于中药丁桂儿脐贴中丁香酚的测定 ,其回收率为 93.3%～ 98.3% ,结果令人满意。通过对化学发光光谱、紫外可见吸收光谱的研究 ,提出其抑制作用机理可能是丁香酚与鲁米诺竞争消耗由二甲亚砜 氢氧化钠 O2 体系产生的O· -2 ,从而使化学发光强度降低     

氢气扩散火焰中辐射源项湍流脉动特征的PDF模拟

采用κ-ε湍流模型、标量联合的概率密度函数(PDF)输运方程和层流火焰面模型相结合,模拟氢气自由扩散火焰中辐射源项湍流脉动特征.给出了主燃区内辐射源项湍流脉动的频率图.辐射源项的样本点分布集中,大约95%以上的样本落在其系综的±3倍方差以内,频谱图为单峰.     

颗粒Reynolds正应力轨道模型及后台阶两相流动数值模拟

用随机过程理论建立气固两相耦合脉动量Lagrange方程,并建立了气固两相流随机颗粒轨道模型中颗粒Reynolds正应力的Lagrange方程.将新的模型运用于各向同性的湍流衰减的流场中,模拟颗粒的湍流扩散特性,与文[1]中的模型和实验结果作比较,并使用新模型模拟了后台阶两相流动.     

A prototype MRPC beam test for the BESⅢ ETOF upgrade

A prototype multi-gap resistive plate chamber (MRPC) with a 2×6 gap structure is developed for the upgrading of the endcap time-of-flight (ETOF) detector in the Beijing Spectrometer (BESⅢ). The prototype MRPC is tested in the E3 beam line of the Beijing Electron Positron Collider (BEPC) with secondary charged particles (π and p, etc) of 600 MeV/c. The test results show that the time resolution of the MRPC can reach 50 ps and that the detection efficiency is greater than 98%.     

Optimization of the three-dimensional electric f ield in IH-DTL

The tuning process of the three-dimensional electric field near the beam axis is very important in the optimization of the Interdigital H-mode Drift Tube Linac (IH-DTL). The tuning of the longitudinal field distribution, the Kilpatrik (Kp) factor, and the transverse dipole field have been discussed in detail, combined with the radio-frequency tuning process of the 53.667 MHz short IH-DTL cavity, which was designed to accelerate ²³⁸U³⁴⁺ from 0.143 MeV/u to 0.289 MeV/u in the SSC-Linac injector project at the Institute of Modern Physics. The flatness criterion and the tube tuning method are discussed in order to meet the beam dynamics requirements. In the tube tuning process, the energy gain error in the cells should be reduced to less than ±2%, and the Kp factor should be reduced to 1.6. The transverse dipole field and the method that uses a "plunger" to dismiss this dipole field are evaluated. The experience gained from the first cavity optimization benefits the tuning process of the three remaining IH-DTL cavities in the SSC-Linac project.     

Low temperature testing and neutron irradiation of a swept charge device on board the HXMT satellite

We present the low temperature testing of an SCD detector, investigating its performance such as readout noise, energy resolution at 5.9 keV and dark current. The SCD's performance is closely related to temperature, and the temperature range of -80 ℃ to -50 ℃ is the best choice, where the FWHM at 5.9 keV is about 130 eV. The influence of the neutron irradiation from an electrostatic accelerator with fluence up to 1×10⁹ cm^-2 has been examined. We find the SCD is not vulnerable to neutron irradiation. The detailed operations of the SCD and the test results of low temperature are reported, and the results of neutron irradiation are discussed.     

强背景下模糊闪烁成像目标探测与跟踪

 强背景下空中运动目标主要表现为边缘残缺、模糊,甚至出现闪烁、间断等复杂成像特性,这成为制约目标探测和成像跟踪的瓶颈问题。结合跟踪过程反馈信息来确定目标点扩展函数,利用一种新的Ben-Ezra图像复原模型,解决了目标运动模糊的图像复原问题;采用基于特征伴随值的相似性判断方法,构造联结机制的联想网络模型,来解决目标闪烁和残缺特征的联想问题。对提出的方法进行了图像序列的仿真,取得了较好的实验结果。     

一种非定常N-S方程并行求解设计

为了解决计算流体力学(CFD)中非定常计算与越来越大的计算量,并行计算已成为一种现实有效的选择.论文首先研究了一种并行区域分解策略,该策略简单而高效,但需要算法配合.为此,采用了一种与并行完全兼容的隐式方法DP-LUR方法.通过双时间步长法,将DP-LUR方法延伸应用到非定常计算中而不改变其原有的性质.最后分析了并行编程中的主要难点,提出解决方法,即采用中间数据分离节点下标与处理,并给出了并行程序的总体结构.     

强激光对典型激光制导光电探测器的干扰效应研究

为了达到对激光制导武器的有效干扰目的,需要分析强激光对典型激光制导光电探测器的干扰效应。理论分析和数值计算表明四象限光电二极管和成像型CCD的光学饱和阈值较低,很容易达到光学饱和。在功率密度10MW/cm2,脉冲宽度5ns的单脉冲激光辐照下即可产生300K的温升,在多脉冲温升的累积作用下,光电探测器的基底材料很容易达到熔点,从而造成不可逆的永久损伤。     

Installation and cosmic ray test of the high voltage system of the BESⅢ drift chamber

After examination of the designed high voltage power supply system of the BESⅢ drift chamber in the beam test of the full length prototype of drift chamber, a full system covering all the channels of high voltage was installed. The system's training and the high voltage value adjustment were carried out in the cosmic ray test of the BESⅢ drift chamber. The cosmic ray test for the full system and its final installation on the BESⅢ drift chamber were reported. The full system of high voltage power supply works stably and reliably.