Applications of operator identities to the multiple q-binomial theorem and q-Gauss summation theorem

In this paper, we first give an interesting operator identity. Furthermore, using the q-exponential operator technique to the multiple q-binomial theorem and q-Gauss summation theorem, we obtain some transformation formulae and summation theorems of multiple basic hypergeometric series.     

Threshold behaviour of a stochastic SIR model

In this paper, we investigate the threshold behaviour of a susceptible-infected-recovered (SIR) epidemic model with stochastic perturbation. When the noise is small, we show that the threshold determines the extinction and persistence of the epidemic. Compared with the corresponding deterministic system, this value is affected by white noise, which is less than the basic reproduction number of the deterministic system. On the other hand, we obtain that the large noise will also suppress the epidemic to prevail, which never happens in the deterministic system. These results are illustrated by computer simulations.     

SWEIA艾滋病毒传染模型及应用

人类免疫缺陷病毒(HIV)是一种严重威胁生命的病毒,感染艾滋病毒患者一般经历四个阶段:i)艾滋病毒阴性的窗口期(W);ii)阳性的无症状潜伏期(E);iii)有症状期(Ⅰ);以及iv)移除阶段(A).为深入研究艾滋病传播过程,建立SWEIA艾滋病毒传染模型,定义基本再生数,分析无病与地方病平衡点的存在性和局部稳定性,根据2004至2015年中国艾滋病患者数据,采用遗传算法对SWEIA模型中参数进行估计.通过对基本再生数敏感性分析以及模型数值随参数不同而产生的变化,揭示艾滋病窗口期的接触率是影响艾滋病流行的主要原因之一.     

关于电学基础课程物理量的量纲与单位的讨论

本文从“量”的等式观点出发,阐述了电学基础课程相关物理量的量纲与单位问题,包括将已知量代入方程的方法,导出量纲与导出单位,标准函数的量纲等。特别指出,单位冲激函数的量纲是倒时间量纲,单位阶跃特性s(t)与单位冲激特性h(t)都是响应与激励量值的某种比值,它们都不具有电压或电流的量纲,不是普通意义上的响应。唯此,卷积积分公式的量纲才能平衡。本文目的是激发广大教师在课程教学中努力探索量纲问题的积极性。     

仲辛基苯氧基乙酸基本常数的测定

在 2 5℃ ,利用两相滴定法测定了仲辛基苯氧基乙酸 (CA 1 2 )在水中的溶解度S ,离解常数Ka,庚烷中的二聚常数K2 和水 庚烷两相间的分配常数Kd 。实验测得S =1 .40× 1 0 - 4mol L ,Ka=3 .0 2×1 0 - 4,K2 =3 .5 6× 1 0 2 ,Kd=4.0 6× 1 0 2 。     

Identification of Genetic Product — Gm-Csf by Hplc-Esims

ABSTRACT

The genetic product, granulocyte-macrophage colony stimulating-factor (GM-CSF) biosynthesized in this university, is identified through techniques of HPLC and ESIMS in the present study. Results indicate that the experimental molecular weight for the product protein is in agreement with the expected one. Partial sequences are inferred from the tryptic peptide map of product protein. Combining the partial sequence and molecular weights of tryptic peptides, the product protein of GM-CSF has been verified through the Swiss-Prot protein database with satisfactory results.     

胺型键合反相固定相的制备及评价

首次将一种新型硅烷偶联剂--β-（3，4-环氧环已基）乙基三甲氧基硅烷（β-ECTS）与辛胺反应，然后再键合到硅胶上，得到了胺型键合固定相，并用元素分析、^13C固体核磁共振、红外光谱进行了表征。以甲醇和水为二元流动相，用包括碱性、酸性和中性有机化合物在内的混合物对该固定相进行评价，并考察了该填料的适用pH范围及水解稳定性。结果表明，该固定相具有较好的色谱性能，且在pH=2-8之间稳定性能良好，可有效地用于碱性化合物的分析分离。     

DTA and FT-IR analysis of the rehydration of basic magnesium carbonate

The rehydration characteristics of a commercially produced hydromagnesite and two basic magnesium carbonates synthetically produced from Mg(OH)₂, are presented. The products were dehydrated and dehydroxylated at 325°C before rehydration was attempted. DTA and FT-IR were used to follow the structural changes that occurred during the rehydration processes. The results obtained for the commercially and synthetically produced hydromagnesite products indicated that the original symmetry of the groups was reclaimed during rehydration. This was not observed for the synthetically produced unidentified basic magnesium carbonate product. This investigation provides insight into the rehydration characteristics of a select group of basic magnesium carbonates. This revised version was published online in July 2006 with corrections to the Cover Date.     

New methods for data analysis of isothermal titration calorimetry

Heat divided by ligand concentration vs. heat, similar to the Scatchard plot, was introduced to obtain the equilibrium constant (K) and the enthalpy of binding (DH) using isothermal titration calorimetry data. Values of K and DH obtained by this linear pseudo-Scatchard plot for a system with a set of independent binding sites (such as binding fluoride ions on urease and monosaccharide methyl a-D-mannopyranoside on concavalin A) were remarkably like that obtained from a normal fitting Wiseman method and other our technical methods. On applying this graphical method to study the binding of copper ion on myelin basic protein (MBP), a concave downward curve obtained was consistent with the positive cooperativity in the binding. A graphical fitting by simple method for determination of thermodynamic parameters was also introduced. This method is general, without any assumption and restriction made in previous method. This general method was applied to the product inhibition study of adenosine deaminase. This revised version was published online in July 2006 with corrections to the Cover Date.