亚甲基蓝化学吸附动力学的SERS研究

用硝酸刻蚀银表面ＳＥＲＳ技术研究了亚甲基蓝在较稀浓度时的化学吸附动力学，对不同振动模式计算了吸附动力学参数，结果表明，亚甲基蓝在银表面上吸附均匀，吸附过程中没有吸附形态间的转化。在亚甲基蓝浓度较高时，我们观察到了与浓度较稀时明显不同的行为，并提出了可能的解释。另外，还考察了Ｃｌ＾－离子对亚甲基蓝在银表面上吸附形态的影响，观察到由“平躺”方式向“独立”方式的转变。     

功能化荧光碳纳米点的一步法制备及其光谱研究

以肝素钠为碳源,采用水热法一步制备了表面功能化的荧光碳纳米点。利用透射电镜、红外光谱、光电子能谱及荧光发射光谱对其形貌、结构和光致发光性质进行了测试分析。研究结果表明,碳纳米点具有较为均一的尺寸和较强的荧光,并且保留了碳源中大量的官能团。制备得到的碳纳米点可应用于Cu2+的检测,显示了其作为离子传感器材料的潜在应用价值。     

铁氰化钆修饰电极对鸟嘌呤的电催化氧化及应用

用电化学沉积法制备了稀土铁氰化钆修饰玻碳电极(GdHCF/GC/CME),考察了该电极对鸟嘌呤的电催化氧化性能,同时根据Fenton反应产生的羟基自由基对鸟嘌呤的氧化作用和修饰电极氧化作用之间的竞争机理,对抗坏血酸清除羟基自由基进行了初步评价.实验结果表明,修饰电极对鸟嘌呤具有很好的电催化氧化性能.在HAc-NaAc缓冲液(pH=5.1)中,鸟嘌呤在1.0×10-6～4.6×10-5 mol/L浓度范围内与其氧化峰电流呈良好的线性关系,其线性回归方程为Ip(μA)=0.1112C 2.8715,r=0.9889;检出限为3.3×10-7 mol/L.以此电极评价抗坏血酸对羟基自由基的清除作用,取得了较好的效果,为羟基自由基清除剂的筛选提供了一种新的方法.     

Functionalized magnetic nanoparticles for drug delivery in tumor therapy

The side effects of chemotherapy are mainly the poor control of drug release. Magnetic nanoparticles(MNPs) have super-paramagnetic behaviors which are preferred for biomedical applications such as in targeted drug delivery, besides, in magnetic recording, catalysis, and others. MNPs, due to high magnetization response, can be manipulated by the external magnetic fields to penetrate directly into the tumor, thus they can act as ideal drug carriers. MNPs also play a crucial role in drug delivery system because of their high surface-to-volume ratio and porosity. The drug delivery in tumor therapy is related to the sizes, shapes, and surface coatings of MNPs as carriers. Therefore, in this review, we first summarize the effects of the sizes, shapes, and surface coatings of MNPs on drug delivery, then discuss three types of drug release systems, i.e., p H-controlled, temperature-controlled, and magnetic-controlled drug release systems, and finally compare the principle of passive drug release with that of active drug release in tumor therapy.     

Capacitance performances of supramolecular hydrogels based on conducting polymers

The capacitance performances of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT-PSS) supramolecular hydrogels have been investigated systematically. The materials show a specific capacitance of 67 F/g and display excellent rate capability at the scan rate as high as 5000 m V/s in the cyclic voltammogram measurements, accompanied by good cycle stability. On the basis of the measurements of the microscale morphologies, specific areas and electrical conductivities, the mechanisms for the improvement of the electrochemical properties are discussed and ascribed to the novel porous microstructures of the hydrogels and the synergetic effect of the rigid PEDOT and soft PSS components. Furthermore, polyaniline(PAn) is compounded with the PEDOT-PSS hydrogels through an interfacial polymerization process, endowing the hydrogel materials with a higher specific capacitance of 160 F/g at the scan rate of 5000 m V/s. The significance of this work lies in the demonstration of a novel method to solve the problems of conducting polymers in electrochemical applications.     

如何讲授体型缩聚中凝胶点预测公式的实际应用

在高分子化学中,形成网络结构的交联作用具有很大的实用意义,因为交联的体型聚合物具有很高的耐热性和优良的机械性能。由于具有受热后软化而不能再流动,故称之为热固性聚合物。一种聚合物一般在实际应用之前要加工成型以得到所需的材料,如在加工之前即已发生凝胶固化,则该聚合物实际上已无法使用。因此,我们在进行体     

聚硅烷研究进展：（I）聚硅烷的合成及应用

聚硅烷的合成及应用因可溶性聚硅烷的发现而成为聚合物研究的又一热点。本文综述了聚硅烷合成与应用的近期发展。     

含苄氨基结构的有机硅单体的合成及固定化的研究

合成了五种含有苄氨基结构的有机硅单体:XCH_2--CH_2 CH_2Si(OCH_3)_3(X=-NH(CH_2)_2CH_3、-NH(CH_2)_3CH_3、-N(C_2H_5)_2、-NH(CH_2)_2NH_2和-NH_2).红外光谱、核磁共振及硅元素分析证实了所合成的单体具有预期的化学结构.通过硅官能团的反应,这些单体可以固定在气相二氧化硅表面而制成载有苄氨基结构的二氧化硅.固定化产物的漫反射红外光谱证实了这点.同时,对水溶液中微量Cu~(2+)吸附的结果表明,固定化产物对Cu~(2+)的捕集均有一定效果而以X=-NH(CH_2)_2CH_3及-NH(CH_2)_2NH_2的为最佳.     

CO氢化合成乙醇反应的过渡应答研究——Ⅱ. 改性Rh/Al2O3催化剂上的反应动力学研究

本文用过渡应答技术研究CO在改性Rh/Al_2O_3催化剂上常压氢化合成乙醇的表面反应机理。结果表明: 1. 在Rh/Al_2O_3催化剂中添加K元素能显著地增加合成乙醇反应的活性和选择性; 2. 乙醇的生成取决于表面上相邻两个含氧中间体的密度而与气相中的H_2或CO浓度无关。反应倾向于ANDERSON的缩聚机理。在此反应机理的基础上, 由应答曲线的数据, 根据MARQUARDT非线性优化技术以及RUNG-KUTTA-GILL数值积分法计算了所有基元步骤的反应速率常数。