Fast and accurate measurement of diffusion coefficient by Taylor’s dispersion analysis

This investigation aimed at improving the performance of Taylor’s dispersion analysis for the fast and accurate measurement of diffusion coefficient of a minute solute in various solvents. The investigation was carried out on a capillary electrophoresis instrument by monitoring the UV absorption peak of a solute pulse and calculating the diffusion coefficient by peak efficiency. With L-phenylalanine as a main testing solute, some key factors were afterward disclosed including especially the capillary size, carrier flow velocity, injection volume and capillary conditioning. Peak tailing, large volume of sample injection and slow migration were found to underestimate the diffusion coefficient while very fast migration and high sample concentration caused overestimation. At a moderate flow velocity of 0.1―1 cm/s with a capillary of 72.44 μm I.D.×60 cm (50 cm effective) maintained at 25℃, the diffusion coefficient of aqueous L-phenylalanine was determined, giving a value of 7.02×10-6 cm2/s with error <2% and relative standard deviation <0.2% (n=3). The method was shown to be applicable to the measurement of various samples such as aqueous phenylalanine, acetone, phenol, toluene and benzene, and nonaqueous benzene (in ethanol or 1-butanol).     

成人型Still’s病人1例

患女,３９岁,以“间断发热１月”之主诉入院。１月前,无明显诱因开始发烧,体温３８－３９℃之间,伴头痛及全身不适,在外院曾予青霉素,氨苄青霉素常规量治疗８天后热退。退热后患者一般情况可,无明显痛苦表情,谈笑自如。２天前再次发烧,体温３９．７－４１℃,改用先锋霉素Ｖ常规量治疗２天,体温不降,遂来我院就诊。发病以来,无四肢关节肿胀及晨僵,无肌痛、肌无力、无胸闷、气短、无咳嗽、咳痰及盗汗、无腹痛、腹泻、二便正常。查体：Ｔ３８．５℃,Ｐ９０次／分,Ｒ２０次／分,Ｂｐｌ６／１０ＫＰａ,腹部散在十几个皮疹,颌…     

Measuring radial Young’s modulus of DNA by tapping mode AFM

Based on tapping mode AFM imaging, a method was demonstrated to evaluate compression elasticity of single double-stranded DNA (dsDNA) molecules in the force region. With images under ambient conditions, Young’s moduli of dsDNA in compression were calculated. Results demonstrated that Young’s moduli of dsDNA can be simply deduced according to the proposed model. The method can also be used to evaluate the compression elasticity of similar soft nanomaterials.     

Gomory’s Method Based on the Objective Equivalent Face Technique

0 IntroductionMyaenayrs co hmavpeuta rtieovneaalled ex tpherati m leinntesar in pr tohgera pmamstin gtw ebantsyebranch-and-bound algorithm with cuts is currently the mostsuccessful tool for attacking combinational and linear integerprogramming problems without any given structure.Such al-gorithms ,are well-known as cutting plane ones , and morespecifically branch-and-cut ones , which have become verypopular toolsin recent years for solvinginteger and mixed-in-teger programs to opti mality (see…     

Nature or Nurture—On the Development of Children’s Language

Referring to children’s development,especially the development of children’s language,there is a question that people are very interested in,that is,does the development of children’s language on earth depend on innate inheritance or postnatal environment? In order to answer this question,this paper begins with the definition of the development of children’s language,then,expounds some theories on language acquisition,finally,finds out the crucial factors influencing the development of children’s language.     

Robust SLAM using square-root cubature Kalman filter and Huber’ s GM-estimator

Mobile robot systems performing simultaneous localization and mapping ( SLAM) are generally plagued by non-Gaussian noise.To improve both accuracy and robustness under non-Gaussian meas-urement noise, a robust SLAM algorithm is proposed.It is based on the square-root cubature Kal-man filter equipped with a Huber’ s generalized maximum likelihood estimator ( GM-estimator) .In particular, the square-root cubature rule is applied to propagate the robot state vector and covariance matrix in the time update, the measurement update and the new landmark initialization stages of the SLAM.Moreover, gain weight matrices with respect to the measurement residuals are calculated by utilizing Huber’ s technique in the measurement update step.The measurement outliers are sup-pressed by lower Kalman gains as merging into the system.The proposed algorithm can achieve bet-ter performance under the condition of non-Gaussian measurement noise in comparison with benchmark algorithms.The simulation results demonstrate the advantages of the proposed SLAM algorithm.     

Mycielski’s图的Co-PI指标

令G是一个图,u是图G的一个顶点, TG（ u）是图G当中除了u以外的其余顶点到点u的距离之和, T（ u）＝TG（ u）＝∑u∈V dG（u,v）,Co-PI指标定义为：Co -PIv（G）＝∑uv∈E（G） T（ u）-T（ v）。文章给出了一些Mycielski’ s图的Co-PI指标的计算公式。     

Management Communication in University’s Digital Library

IntroductionAmericanfuturologistNaisbitthadsaid :“Futurecompetitionisthecompetitionofmanagement,thefocusofwhichistheeffectivepersonnelcommunicationandcross organizationalcommunication.”[1]Communicationisthetransferringprocessofinformation ,knowledgeandemotionamongindividualsandgroups,throughwhichaf fectothers’attitudesandfeelings,andeventuallyaffecttheirbehaviors.Forknowledgehasbeentheprimacyele ment,managementcommunicationinknowledgeeconomicagesismoreimportantthananyotherepoch ,whosestyle…     

P?un’s systems as models of economic systems

In the paper a concept for modeling the economic systems by the formalism of P?un’s systems is proposed. The main idea is to represent economic systems as homomorphic images of Petri nets corresponding to the (super) cells of P?un’s systems.     

P?un’s systems as models of economic systems

In the paper a concept for modeling the economic systems by the formalism of P?un’s systems is proposed. The main idea is to represent economic systems as homomorphic images of Petri nets corresponding to the (super) cells of P?un’s systems.     

Tobin’s Q与股票价格相互关系的实证研究

自从1969年詹姆斯·托宾提出Tobin’s Q理论以来,大量的文献研究Tobin’s Q作为成长性指标的内在经济含义。本文选取2003年至2006年间上证180与深证100指数成份股作为研究对象,考察Tobin’s Q与我国股票价格的相互关系。研究发现,对于我国股市而言,在2003至2006年这段时期内,Tobin’s Q与股票价格的关系要分为两个阶段,2003、2004年,Tobin’sQ与股票价格相关性不是很明显;2005、2006年,Tobin’s Q与股票价格呈现明显的正相关性。     

Least Privileges and Role’s Inheritance of RBAC

0 IntroductionRoalse -abna asletder ancacteisvse caonndt rsoulp p(lRemBeAnCt) t oh tahse b tereandi tcioonnsaild edries-dcretionary and mandatory access controls (DAC and MAC) .In RBAC,permissions are associated withroles ,and users aremade members of appropriate roles thereby acquiring theroles’permissions[1-4]. Unfortunately,since thereis still lackof specific definition and the necessary formalization forRBAC[5],the well-known security principles and the inherit-ance of roles cannot…     

厚尾噪声条件下星凸形扩展目标student’s t滤波器

针对非线性非高斯厚尾噪声条件下的不规则形状的扩展目标跟踪问题,提出了基于随机超曲面模型(RHM)的星凸形扩展目标student’s t滤波算法.首先,在带有非高斯厚尾过程噪声和厚尾量测噪声的系统中, 基于student’s t分布给出鲁棒student’s t滤波器.其次,利用随机超曲面模型描述任意星凸形扩展目标的量测源分布, 提出带厚尾噪声的星凸形扩展目标student’s t滤波器.最后通过仿真验证了所提方法的正确性和有效性.     

层次化的K.Fan’s Theorem

在L-拓扑空间中,对任意LF集,我们利用层次化的K.Fan’s Theorem定义了一种层次连通并研究了其基本性质.     

改进的Fan’s代数方法及其应用

借助计算机符号系统Maple,利用改进的Fan’s代数方法求解（2＋1）维NNV方程,得到了一系列显式精确解,包括孤立波解、类孤立波解、纽结波解、奇异纽结波解和三角函数周期解.     

一类光滑Chua’s电路的自适应同步

本文讨论了一种变形的光滑Chua’s电路的同步控制问题.当从动系统对主动系统的参数未知时,采用Lyapunov稳定性理论和自适应设计方法,设计出一个自适应控制器.通过该控制器,实现了主从系统间的自适应同步.仿真结果表明该设计方法是有效的.     

Infection of SARS-CoV on juvenile and adult Brandt’s vole Microtus brandtii

In the spring of 2003, severe acute respiratory syndrome (SARS) suddenly broke out in many countries of the world, especially China. About 8400 probable cases of SARS were identified worldwide and about 800 patients died. SARS not only caused severe panic all over the world, but also brought huge losses to global economy. SARS is recognized as a new kind of respiratory disease, caused by a novel coranovirus, SARS-CoV. It is characterized by pneumonic infection and pathological change.…     

Moran’s I指数与DEM 网格大小关系的研究

数字高程模型(Digital Elevation Model,简称DEM)作为真实地形的一种数字化模拟,网格间存在着某种空间自相关性.Moran’s I是一种常见的空间自相关程度量化指标.为了研究Moran’s I与DEM网格大小之间的关系,文章在分辨率为30 m×30 m的DEM上随机选取了35个采样点.又以每个采样点为中心,选取n×n(n=3,5,7,…,25)大小的DEM网格,计算并记录对应于每个网格的Moran’s I指数值,绘出各采样点的Moran’s I指数值随n变化的曲线.研究发现:大多数采样点的Moran’s I曲线呈现出一致的变化趋势;同时发现少数采样点的Moran’s I曲线出现局部的变化异常.对这些异常进行分析后发现,Moran’s I值随n变化的趋势与DEM网格高程值的离散程度(地形)有关.     

Poet’s Escapism and Speaker outside the Poem——William and Dorothy in Composed Upon Westminster Bridge,Sept.3,1802

This paper analyses the author’s escapism In this Composed Upon Westminster Bridge, Sept. 3, 1802 ,and conclusion is reached that the poet wrote this particular poem for his beloved sister. And the sister ’s calmness and complacency came to be the best pill to heal the wounds of the poet.