卤代苯甲酸-TPTZ铽配合物的合成、表征及荧光性能

分别以对溴苯甲酸和对碘苯甲酸为第一配体,2,4,6.三吡啶基三嗪(TPTZ)为第二配体,以铽为中心,La3+、Y3+、Cd3+为掺杂离子,合成了8种铽及其掺杂配合物,对其进行了C、H、N元素分析及稀土络合滴定、紫外光谱、红外光谱和荧光光谱测定.推测配合物的组成为:Tb(P-BrBA)3(TPTZ)·2H2O和Tb(P-...     

A computer model of pulse wave and input impedance in human arteries

To predict the propagation of pressure and flow pulses in arterial system and the variation of vascular input impedance, a branched and tapered tube model is studied through one-dimensional transient flow analysis. Coupling the continuity and momentum equations yields a group of quasilinear hyperbolic partial differential equations which can be solved numerically by using the method of characteristics. Several boundary conditions of the arterial system are also simplified suitably. The propagation of the pulses of the arterial system and the vascular input impedance is calculated on computer by using the dimensions and the physiological data of the arterial system. The results point out that the pressure and flow pulses of the arterial system and the vascular input impedance produced by this theoretical model is consistent quite well with the experimental results published.     

人体体动脉脉搏波和输入阻抗的计算机模拟

本文通过对具有连续出流的分支、锥削管的一维非线性瞬态流分析,研究了人体体动脉中压力和流量脉搏波的传输和血管输入阻抗的变化规律.通过耦合支配着动脉中脉搏波传播的连续性方程和运动方程,文章导得了一组可以用特征线法求解的拟线性双曲型偏微分方程组.同时,对血管系统中常见的几种边界条件进行了适当的处理.文章利用血管几何参数和物理参数的生理实验数据,对血管系统的脉搏波传播和输入阻抗进行了计算机模拟.结果表明,从本文提出的分析模型得到的压力和流量波形以及输入阻抗与有关文献公布的实验结果吻合得相当好.     

用循环图构造可靠通讯网络

本文得到了５度、７～１５度连通循环图的连通度等于其度数的充要条件。从而可用循环图构造可靠通讯网络。     

A COMPUTER MODEL OF PULSE WAVE AND INPUT IMPEDANCE IN HUMAN ARTERIES

To predict the propagation of pressure and fiow pulses in arterial system and the variation of vascular input impedance, a branched and tapered tube model is studied through one-dimensional transient flow analysis. Coupling the continuity and momentum equations yields a group of quasilinear hyperbolic partial differential equations which can be solvednumerically by using the method of characteristics. Several boundary conditions of the arterial system are also simplified suitably. The propagation of the pulses of the arterial system and the vascular input impedance is calculated on computer by using the dimensions and the physiological data of the arterial system. The results point out that the pressure and flow pulses of the arterial system and the vascular input impedance produced by this theoretical model is consistent quite well with the experimental results published.     

杂多酸催化剂上甲醇转化为烃的研究

Keggin型杂多酸化合物的热稳定性高,又具有强酸性和氧化还原性,故其催化作用很引人注目.由于其结构上的特点,反应物分子能出入催化剂的体相内部,因而体相中的活性中心也起作用,被称作“假液相”催化.杂多酸用于甲醇催化转化为烃的反应有不少研究.据报道,12-钨磷酸(H_3PW_(12)O_(40))和12-钨硅酸(H_4SiW_(12)O_(40))、12-钨磷酸铜(Cu_(3/2)PW_(12)O_(40))对甲醇转化反应都有相当高的活性.1,4-二嗪和1,3,5-三嗪的12-     

新型蒙脱土修饰膨胀石墨电极对苯胺的电化学检测

以十二烷基二甲基苯甲基氯化铵为层间模板剂、四乙氧基硅烷为插层剂制备了插层蒙脱土(MMT),相比于未经插层改性的MMT,插层MMT的比表面积显著增大.利用插层MMT对膨胀石墨进行修饰,从而制备了新型MMT修饰膨胀石墨电极,采用差分脉冲伏安法对苯胺进行测定.结果表明:苯胺在经过插层MMT修饰后的膨胀石墨电极上的氧化峰电流大幅度提高.苯胺的氧化峰电流与其浓度在10～1 000 μmol/L范围内呈现良好的线性关系,检出限为6.05 μmol/L,并且常见物质对苯胺的检测并无干扰.用5支插层MMT修饰膨胀石墨电极平行测定1.0 mmol/L苯胺溶液,相对标准偏差(RSD)为3.83％.采用该修饰电极进行空白加标回收实验,回收率为96％～101％.     

对氯苯甲酸-2,4,6-三吡啶基三嗪稀土配合物的合成、表征及发光性能

以对氯苯甲酸为第一配体,2,4,6-三吡啶基三嗪(TPTZ)为第二配体,分别以铕、铽和镝为中心,合成了10种稀土配合物,并进行了元素分析、稀土络合滴定、等离子光谱、紫外光谱、红外光谱和发光光谱测定。配合物的组成为:RE(p-ClBA)3(TPTZ).2H2O和RE0.5Ln0.5(p-ClBA)3(TPTZ).2H2O(RE=Eu3+,Tb3,+Dy3+;Ln=La3,+Gd3,+Y3;+p-ClBA=对氯苯甲酸根;TPTZ=2,4,6-三吡啶基三嗪),均为非电解质;对氯苯甲酸的羧基氧原子与稀土离子配位,2,4,6-三吡啶基三嗪以主配位点上的3个氮原子与稀土离子配位;铕配合物的发光强度大于铽配合物的,镝配合物发光最弱;在上述3种发光稀土配合物中分别掺入发光惰性稀土离子镧、钆及钇后,发光强度有不同改变,掺入镧可明显增强铕、铽的发光强度,钆可敏化铕、铽和镝的发光,而钇的敏化作用较弱。表明:掺杂配合物并不完全是两种简单配合物的机械混合,而是有混配配合物生成。     

硫氮共掺杂碳量子点荧光识别Pb~(2+)

以L-半胱氨酸为碳源、硫源及氮源,一步水热法制得水溶性好、稳定性高的硫氮共掺杂碳量子点SN-CDs。基于Pb~(2+)对其荧光的淬灭作用,构建了高选择性与高敏感度的荧光探针,可应用于Pb~(2+)的快速检测。运用透射电镜、紫外-可见吸收光谱、Fourier红外光谱和荧光光谱表征了SN-CDs的结构及光学性能。结果表明,Pb~(2+)浓度在2～50μmol/L范围内,与SN-CDs的荧光淬灭率之间呈良好的线性关系,相关系数为0.9992,检出限为0.2μmol/L。方法用于自来水中Pb~(2+)的测定,回收率为94.7%～100.7%。