PVP/Pd/IrO_2/Nafion修饰微电极用于成纤维细胞中一氧化氮释放的研究

采用PVP/Pd/IrO_2/Nafion修饰电极对成纤维细胞中NO的释放情况进行了研究 。结果表明,在正常状态下,采用NO前体L-精氨酸和乙酰胆碱对成纤维细胞进行刺 激后没有NO的释放;当用脂多糖进行诱导后,则释放出高浓度的NO,加入L-精氨酸 和乙酰胆碱都促进了NO的合成,而L-NNA的加入则逆转了L-精氨酸和乙酰胆碱的作 用。     

Sodium atom in strong magnetic fields：a pseudospectral approach

Energies and wavefunctions of low-lying states and Rydberg states for the sodium atom in uniform magnetic fields varying from 0 to 10^5T are calculated using a pseudospectral approach with a model potential in spherical coordinates. The energies are comparable with experimental results as well as those obtained by other calculations. The spectra of oscillator strength are worked out. The evolution of them with the magnetic field is shown.     

The isolated critical value phenomenon in local－global riddling bifurcation

A chaotic synchronized system of two coupled skew tent maps is discussed in this paper. The locally and globally riddled basins of the chaotic synchronized attractor are studied. It is found that there is a novel phenomenon in the local－global riddling bifurcation of the attractive basin of the chaotic synchronized attractor in some specific coupling intervals. The coupling parameter corresponding to the locally riddled basin has a single value which is embedded in the coupling parameter interval corresponding to the globally riddled basin, just like a breakpoint. Also, there is no relation between this phenomenon and the form of the chaotic synchronized attractor. This phenomenon is found analytically. We also try to explain it in a physical sense. It may be that the chaotic synchronized attractor is in the critical state, as it is infinitely close to the boundary of its attractive basin. We conjecture that this isolated critical value phenomenon will be common in a system with a chaotic attractor in the critical state, in spite of the system being discrete or differential.     

关于数列{2~n}

易知等比数列{2~n}前n项的和为S_n=a_(n+1)-2。对于这个关系式,我们有三点联想。 (一)简便求和。若a_5=32,则S_4=30。 (二)判定由关系式a_(n+1)=rS_n+S给出的数列是否为等比数列。事实上a_(n+1)=rS_n+S (1) a~n=rS_(n-1)+S (2) (1)-(2)得a_(n+1)-a_n=r(s_n-S_(n-1))=ra_n a_(n+1)/a_n=r+ 因此,r≠-1,a_1=S,{a_n}为等比数列。 (三)等比数列前n项和公式的新法推导。     

X射线荧光滤纸片法分析稀土样品谱线间干扰系数的求得和应用

X射线荧光谱法分析稀土元素时,采用滤纸片法制样,引起测量误差的问题报道中已有讨论。由于滤纸上吸附样品量仅1—2mg,一般认为基体效应可以忽略,但稀土元素谱线间的干扰是严重的问题。本文主要是探讨稀土元素谱线间干扰系数的求得及将其应用于混合稀土样品分析。     

常微分方程解的存在唯一性定理教学研究

探讨了常微分方程初值问题解的存在唯一性定理教学策略.为便于教学和有利于学生理解并掌握其思想方法,对定理证明过程的表述作了命题化处理,给出了Picard逐步逼近法的应用实例,提出了教学讨论与知识拓展的一些有益内容.     

基于电化学引发的迈克尔加成反应:终端邻苯氢醌与金属离子络合的电化学行为研究

氢醌/醌型化合物的界面电化学行为研究引起了广泛的关注,而实现该类型电子媒介体在电极表面的高效固载是研究其界面电化学行为的关键.本研究将自组装技术与电化学技术相结合,采用电化学引发的迈克尔加成反应,成功实现了表面受限的氧化还原媒介体氢醌/醌在金电极表面的稳定高效固载.电化学引发迈克尔加成反应作为一种更加灵活与方便的策略,既可以实时监控电活性物质在电极表面固载的动力学过程,又容易调控固载在电极表面的电活性物质的量.     

(±)-Yaequinolone A2的简洁全合成

由廉价的邻氨基苯甲酸为起始原料经6步反应以27.8%的总产率首次合成了2-喹啉酮类生物碱(±)-yaequinolone A2,关键步骤为MOM保护的α-羟基酰胺进行的高非对映选择性分子内aldol 反应。