用标准件对梯度磁场定标

就标准厚度卡片在霍尔传感器的定标方面的应用作了有益的探讨。在纵向测量微小长度时,霍尔片处于磁场边缘位置,其对磁场的梯度更大,即灵敏度更高,且靠中心位置的线性更好。     

基因组重排问题的一个近似算法

分子生物学中基因无方向的反向基因组重排问题在数学上已被证明是一个NP困难问题．基于断点图的概念，给出一个时间复杂性为O(max{b^(π)，nb(π)})，空间复杂性为0(n)的求其近似最优解的算法．其中n为基因组中基因个数，π=(π1,π2，…，πn)表示n个基因的一种排列，b(π)表示排列π中的断点数．数据实验的结果表明，该近似算法可以求得较好的结果．     

并行“冒泡”排序算法的改进

并行“冒泡”排序算法的改进黄干平（武汉大学计算机科学系,武汉,４３００７２）关键词排序,并行算法,冒泡中国法分类号ｗ３０１．６ＰＢＳＭ并行排序算法是对ＫａｚｕｈｉｒｓＳａｄｏ和ＹｏｓｈｉｈｉｄｅＩｇａｒａｓｈ的并行“冒泡’书ｒ序算法’“的改进,其并行...     

液相组合合成的纯化方法

综述了近8年来液相平行合成和组合合成中应用的不同技术, 包括可溶性载体、氟合成技术、离子液体、固相试剂树脂以及低聚乙烯二醇(OEG)衍生物的应用等几方面内容. 论述了它们的基本原理以及相关的应用实例, 并着重强调了目标化合物的分离纯化方法.     

Performance of a sound card as data acquisition system and a lock-in emulated by software in capillary electrophoresis

The performance of fluorescence detectors in capillary electrophoresis is maximized when the excitation light intensity is modulated in time with optimal frequencies. This is especially true when photomultiplier tubes are used to detect the fluorescent light. The photomultiplier tube amplified raw output signal can in principle be captured directly by a personal computer sound card (PCSC) and processed by a lock-in emulated by software. This possibility is demonstrated in the present work and the performance of this new setup is compared with a traditional data acquisition system. The results obtained with this “PCSC and lock-in emulated by software” were of the same quality or even better compared to that obtained by conventional time integrators (Boxcars) and data acquisition boards. With PCSC the limits of detection (LOD) found for both naphthalene-2,3-dicarboxaldehyde-derivatized tyrosine and alanine were 3.3 and 3.5 fmol (injection of 5 nL of samples at 0.66 and 0.70 μmol/L), respectively. This is at least three times better compared to conventional systems when light emitting diodes (LEDs) are used as the excitation source in fluorescence detectors. The PCSC linear response range was also larger compared to conventional data acquisition boards. This scheme showed to be a practical and convenient alternative of data acquisition and signal processing for detection systems used in capillary electrophoresis.     

缩短单点作业时间影响因素的排序研究

提出国家电网公司在实施设备的检修作业时尽量减少停电时间,以实现电缆线路状态的有效监控的重要意义.分析缩短单点作业时间的末端影响因素.提出三角模糊集、指数模糊集用于权重设置的具体途径,应用OWA算子于因素排序评价数值的加权,并拓展其基本原理和方法,使其对极端评分值有所抑制对中间评分值有所提升.以上海市电力公司检修公司为研究背景,应用直觉模糊集及其IFHA集成方法于缩短单点作业时间的末端影响因素评价指标排序,并得出u_≥u_≥u_1u_4u_6≥u_2u_3的结论.     

Computational modelling of multi-material energetic materials and systems

ABSTRACT

In this paper, we present a systematic roadmap for developing a robust and parallel multi-material reactive hydrodynamic solver that integrates historically stable algorithms with new and current modern methods to solve explosive system design problems. The Ghost Fluid Method and Riemann solvers were used to enforce appropriate interface boundary conditions. Improved performance in terms of computational work and convergence properties was achieved by modifying a local node sorting strategy that decouples ghost nodes, allowing us to set material boundary conditions via an explicit procedure, removing the need to solve a coupled system of equations numerically. The locality and explicit nature of the node sorting concept allows for greater levels of parallelism and lower computational cost when populating ghost nodes. Non-linear numerical issues endemic to the use of real Equations of State in hydro-codes were resolved by using more thermodynamically consistent forms allowing us to accurately resolve large density gradients associated with high energy detonation problems at material interfaces. Pre-computed volume tables were implemented adding to the robustness of the solver base.     

基于实时无标记技术研究流式分选后细胞活性的检测方法

利用流式细胞法、细胞计数试剂盒（CCK-8）法、实时细胞功能分析（RTCA）法分别检测分选前后细胞的活性,综合比较了3种方法的检测原理、操作特点等。结果显示,流式细胞法测得的分选后细胞凋亡率为（3.85 ± 0.008）%,分选前细胞凋亡率为（14.09 ± 0.021）%,分选后细胞凋亡率低于分选前,具有统计学差异（P < 0.05）;分选前后的活细胞比例显示,分选后活细胞比例高于分选前,具有显著性统计学差异（P < 0.001）。CCK-8法测得的分选后细胞活性高于分选前,具有显著性统计学差异（P < 0.001）;RTCA法测得的分选后细胞连续增殖活性明显高于分选前,具有极显著性统计学差异（P < 0.000 1）。结果显示,相较于CCK-8法和流式细胞法,RTCA法的细胞用量少、可回收,操作简便,无需标记,检测灵敏度高,可获得实时动态的细胞生长曲线,适合研究分选后细胞长效动态的活性变化,可为基础和临床分选后活细胞的功能研究提供检测手段。     

Zn2+‐Regulated Self‐Sorting and Mixing of Phosphates and Carboxylates on the Surface of Functionalized Gold Nanoparticles

Herein, we describe the self‐sorting of phosphate‐ and carboxylate‐containing molecules on the surface of monolayer‐protected gold nanoparticles. Self‐sorting is driven by selective interactions between the phosphate probe and Zn²⁺ complexes in one monolayer; these interactions force the carboxylate probe to move to a second type of nanoparticle. This process effectively separates the probes and causes their localization in well‐defined spaces surrounding the nanoparticles. The removal/addition of Zn²⁺ metal ions from the system is used to convert the system from an ordered to a disordered state and vice versa. The possibility to control the location and transport of populations of molecules in a complex mixture creates new perspectives for the development of innovative complex catalytic systems that mimic nature.