Theoretical Study on Equation of State of Porous Mo and Sn

We present a first-principles scheme to investigate the equation of state （EOS） of porous materials, based on our recently developed modified mean-field potential approach. By taking the effect of the structural parameters on the free energy into account, we calculate the total energy of materials with initial different densities and then study the EOS of porous Mo and Sn as a prototype. The calculated results are in good agreement with the experimental data available, which demonstrates that our scheme is suitable for investigating EOS of porous materials over a wide r~nge of porosities and pressures.     

氢氘物态方程研究进展

针对近二十多年的氢氘物态方程理论研究工作进行了综述分析,结合本课题组改进的自由能模型、直接量子蒙特卡洛和量子分子动力学方法的模拟结果,对多个研究小组采用不同方法获得的氢氘宽区物态方程数据进行了定量评估分析。结果表明:在当前理论框架下,仅基于第一原理数值模拟得到的氢氘物态方程能够描述的热力学相空间有限;多模型集成的H-REOS.3数据库在105K以下温度与数值模拟结果的相对差别较大,且数据稀少,二者均不能满足工程应用需求。建议采用基于半经验模型的宽区域物态方程研究方法,即结合高精度的实验研究、数值模拟和解析模型,构建满足工程应用需求的氢氘宽区实用物态方程。     

激光诱导荧光毛细管电泳法优化随机寡核苷酸文库聚合酶链反应扩增的条件

寡核苷酸文库的聚合酶链反应(PCR)扩增是指数富集系统配基进化技术(SELEX)筛选适配子技术中的重要步骤.本研究采用毛细管电泳技术结合激光诱导荧光检测器(CE-LIF),通过对双链产物、PCR副产物以及剩余引物的考察,研究了寡核苷酸文库PCR扩增时的影响因素,并对其进行优化.结果表明,随机寡核苷酸文库的扩增与传统均一模板的扩增显著不同,其在扩增十几个循环时产物就达到最大值;此外,初始模板数、退火温度、DNA聚合酶浓度等条件也有所不同.因此, 在进行SELEX筛选之前必须对文库PCR条件进行详细优化.本研究中N39文库优化后的PCR扩增条件为:初始模板的量为105个分子,DNA聚合酶浓度0.05 U/μL,退火温度70 ℃,18个循环.本研究为利用SELEX技术有效筛选适配子,降低筛选的假阳性及提高特异性提供了参考依据.     

机动目标跟踪的自适应相互作用多模型算法

 针对目标跟踪中的目标机动问题提出了一种“基于自适应相互作用多模型”的算法。使用不同的几个子模型来描述目标的运动状态，各个模型有自己的随目标估计状态和当前测量值变化的模型概率,并且各模型之间能通过马尔可夫链的控制自动平滑切换。仿真实验表明了该算法能很好地适应目标的机动，即使采用两个子模型来描述目标的运动，跟踪精度也比较好。     

Mean-field potential calculations of high-pressure equation of state for BeO

A systematic study of the Hugoniot equation of state, phase transition, and the other thermodynamic properties including the Hugoniot temperature, the electronic and ionic heat capacities, and the Gruneisen parameter for shockcompressed BeO, has been carried out by calculating the total free energy. The method of calculations combines first-principles treatment for 0 K and finite-T electronic contribution and the mean-field-potential approach for the vibrational contribution of the lattice ion to the total energy. Our calculated Hugoniot is in good agreement with the experimental data.     

金属铍热力学性质的理论研究

使用第一性原理方法结合平均场模型研究了压力从0到150GPa、温度从0到1500K，金属铍六角密排结构(hcp)的热力学性质，包括铍的常态性质，等温高压物态方程，以及常压下平衡体积、体弹模量随温度的变化，Hugoniot曲线等.0K物态方程由广义梯度近似下的密度泛函理论计算，粒子热运动的贡献由平均场模型计算.由于铍的Debye温度比较高，计算自由能时考虑了零点振动能修正.计算结果与已有的静力学和冲击波实验数据符合得非常好. 关键词： 热力学性质 物态方程 第一原理计算     

Anisotropic and mutable magnetization in Kondo lattice CeSb_2

We have systematically studied the behaviors of the resistivity and magnetization of CeSb_2 single crystals as a function of temperature and external field. Four anomalies in the resistivity/magnetization-versus-temperature curves are observed at low magnetic field. They are located at 15.5 K, 11.5 K, 9.5 K, and 6.5 K, corresponding to the paramagnetic–magnetically ordered state(MO), MO-antiferromagnetic(AFM), AFM–AFM, and AFM–ferromagnetic(FM) transitions, respectively.The anomaly at 9.5 K is only visible with H‖[010] by magnetic susceptibility measurements, indicating that the AFM–AFM transition only happens along [010] direction in ab-plane. The four magnetic transitions are strongly suppressed by high external field. Finally, the field-temperature phase diagrams of CeSb_2 with different orientations of the applied field in ab-plane are constructed and indicate the highly anisotropic nature of the magnetization of CeSb_2.     

无胶筛分毛细管电泳法测定猕猴血浆中的反义寡核苷酸药物癌泰得

采用两步固相萃取(SPE)法结合无胶筛分毛细管电泳(NGCE)技术建立了猕猴血浆中的反义寡核苷酸药物癌泰得的定量分析方法。优化并确定了SPE的相关条件(阴离子交换柱,上样缓冲液pH值为9.0,上样体积及洗脱体积分别为5 mL和3 mL)和NGCE的分析条件(灌胶时间为30 min,分离电压为24 kV)。在优化的条件下,猕猴血浆中癌泰得在1.95～250 mg/L范围内呈良好的线性关系,定量限(LOQ)为1.95 mg/L。批内准确度为93.38%～100.71%,批内相对标准偏差＜11%;批间准确度为89.46%～103.46%,批间相对标准偏差＜9%。在不同条件(室温下存放4 h; 4 ℃下存放24 h;反复冻融（-80 ℃至室温）2次;-80 ℃下保存1个月)下癌泰得在猕猴血浆中的稳定性良好。已将该方法成功地应用于癌泰得的猕猴药代动力学研究。     

Multi-phase-field simulation of austenite peritectic solidification based on a ferrite grain

A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary austenite on the surface of the ferrite equiaxed crystal grain are used as the initial conditions. The simulation shows the multiple interactions of ferrite, austenite, and liquid phases, and the effects of carbon diffusion, which presents the non-equilibrium dynamic process during Fe-C peritectic solidification at the mesoscopic scale. This work not only reveals the influence of the austenite nucleation position, but also clarifies the formation mechanism of liquid phase channels and molten pools. Therefore, the present study contributes to the understanding of the micro-morphology and micro-segregation evolution mechanisms of Fe-C alloy during peritectic solidification.     

两种重组抗CD20人源化单克隆抗体定量分析方法的比较及其在药代动力学研究中的应用

采用酶联免疫吸附分析(ELISA)与基于Wil2-S细胞的流式细胞术(FCA)两种方法对生物基质中的重组抗CD20人源化单克隆抗体(rh-anti-CD20zumab)进行定量分析,并对两种方法进行系统比较。方法学验证结果表明,两种方法均具有良好的特异性、精密度和准确度,但定量范围存在明显差异。ELISA法批内和批间精密度均小于19.5%,准确度为-18.2%~17.6%;FCA法批内和批间精密度均小于19.0%,准确度为-18.9%~18.4%。二者定量范围分别为0.04~5.0 mg/L和3.1~200 mg/L,ELISA法的灵敏度显著高于FCA法。利用两种方法测定猕猴静脉滴注rh-anti-CD20zumab后的血药浓度-时间变化并进行药代动力学(PK)分析。结果表明,在给定剂量下,通过两种方法获得的PK结果具有良好的一致性。FCA法是一种细胞表面抗原靶向性抗体类药物PK研究及药效动力学(PD)研究的快捷、理想的方法。