Molar conductivity calculation of Li-ion battery electrolyte based on mode coupling theory

A method is proposed to calculate molar conductivity based on mode coupling theory in which the ion transference number is introduced into the theory. The molar conductivities of LiPF6, LiClO4, LiBF4, LiAsF6 in PC (propylene carbonate) are calculated based on this method. The results fit well to the literature data. This presents a potential way to calculate the conductivities of Li-ion battery electrolytes.     

Fluorescent sensors for the enantioselective recognition of mandelic acid: signal amplification by dendritic branching

Novel chiral bisbinaphthyl compounds have been synthesized for the enantioselective fluorescent recognition of mandelic acid. By introducing dendritic branches to the chiral receptor unit, the fluorescence signals of the receptors are significantly amplified because of the light-harvesting effect of the dendritic structure. This has greatly increased the sensitivity of the sensors in the fluorescent recognition. Study of the three generation sensors demonstrates that the generation zero sensor is the best choice for the recognition of mandelic acid because of its greatly increased fluorescence signal over the core and its high enantioselectivity. This sensor is potentially useful for the high throughput screening of chiral catalysts for the asymmetric synthesis of alpha-hydroxycarboxylic acids.     

甘薯开花规律的观察

对甘薯的开花规律作了观察．结果表明,一个植株的花序有30－75个,开花顺序有先后．在一个植株上,花是从下而上开放的;在一个花序上,花由内向外开放,它的开花情况符合两种模式图．从每一个植株纵向开花来看,花是从下而上呈螺旋报开放．     

New bounds on time and number of processors for multiprocessor optimal schedules

Two problems for task schedules in a multiprocessor parallel system are discussed in this paper:

1. Given a partially ordered set of tasks represented by the vertices of an acyclic directed graph with their corresponding processing times, derive the lower bound on the minimum time(LBMT) needed to process the task graph for a given number of processors.
2. Determine the lower bound on minimum number of processors(LBMP) needed to complete those tasks in minimum time. It is shown that the proposed LBMT is sharper than previously known values and the computational aspects of these bounds are also discussed.

     

气相色谱质谱法快速测定人血浆中克仑特罗

血浆样品经0.01mol·L-1盐酸和无水乙醇浸取,在碱性条件下用氯仿萃取,GG-MS-选择离子测量法测定,外标法定量。在选定的色谱条件下,盐酸克仑特罗的检出限为0.05ng,线性范围为0.1-100ng,方法的平均回收率为95.6％,RSD小于6.82％(n=6)。该法毋需衍生化,基质无干扰,简便可靠,适用于生物材料中克仑特罗的快速分析。     

Continuous electrophoretic separation of106Ru species in sea water and uptake of the separated fractions by sea algae

¹⁰⁶Ru chloro and nitrosyl-nitrato complexes in sea water were separated into several species by continuous electrophoresis on a filter paper curtain. Biological uptake experiments were carried out on sea algae Fucus virsoides with fractionated¹⁰⁶Ru chloro and nitrosyl-nitrato complex species in sea water. The biological uptake of¹⁰⁶Ru chloro complex species was about 8 times higher than the uptake of¹⁰⁶Ru nitrosyl-nitrato species. Electrophoretically most mobile electrically positively charged cationic species in both systems also showed about 8 times higher biological uptake than the most mobile negatively charged anionic species. A close relation of the biological uptake to the sign of the electrical charge and the electrophoretic mobility of the species is demonstrated. The results are discussed with respect to possible danger to the biological environment as a consequence of the aging of ruthenium species in sea water resulting from¹⁰⁶Ru waste disposal to the sea from a nuclear reprocessing plant. On leave of absence from the National Institute of Radiological Sciences, 9-1, 4-chome, Anagawa, Chiba-shi, Japan, on a fellowship from The Science and Technology Agency of the Japanese Govemment.     

工艺规划中的组合优化问题

为了解决在工艺规划的诸多环节（如工步排序、机床负荷分配、切削参数选择等）普遍存在的组合优化问题，在分析传统方法缺陷的基础上，把一种先进的优化算法——模拟退火算法应用到工艺规划中，并针对加工中心上工步排序这一典型问题，建立组合优化数学模型，对该算法在工艺规划中的运用机理作了详细论述。结果表明，该算法把概率引入到启发式方法中，避免了陷入局部最优点的缺陷，在优化结果和计算时间方面都有明显优于常规方法，有效地提高了工艺规划系统的优化能力。     

DRDOS攻击及其防范

DOS攻击是一种常见、有效而简单的网络攻击技术,而且DOS攻击的手法也在不断发展,现已出现了威胁更大的DDOS和DRDOS。主要介绍了DDOS和DRDOS攻击的概念和原理,并提出了针对整个系统的防范对策。