蒙脱石修饰碳糊电极测定氨基酸的研究：Ⅱ.酪氨酸的测定

本文报道蒙脱石修饰碳糊电极测定酪氨酸，在０．００１ｍｏｌ／Ｌ ＫＣｌ－ＨＣｌ（ｐＨ＝２．０）溶液中开路富集，介质交换后微分脉冲阳极溶出伏安法测定，在０．５－２．５μｇ／ｍｌ范围内有线性，检测限为６３ｎｇ／ｍｌ。可避免其他氨基酸，微量元素和常量金属元素的干扰，直接用于氨基酸药物样品的分析，获得了满意的结果，还对酪氨酸在电极上的反应机理进行了探讨。     

二氧化碳多相催化加氢的新进展

就近年来关于ＣＯ２活化、几个重要的ＣＯ２多相催化加氢反应及廉价氢的供给的研究进展进行综述。参考文献３４篇。     

一种用于空气中二氧化碳现场测定的新方法

一种用于空气中二氧化碳现场测定的新方法于爱民，杨广德，王锐，金钦汉（吉林大学化学系，长春１３００２３）关键词微波诱导等离子体，离子化检测器，气相色谱仪，二氧化碳二氧化碳在植物生长代谢及其生态平衡过程中起着重要作用，现场测定二氧化碳是目前农业、环境科学...     

On the physical adsorption of gases on carbon materials from molecular simulation

In this paper we present a series of work covering a range of aspects relating molecular simulation to experiment. The importance of surface mediation type effects to the adsorption of simple and complex gases is demonstrated. Coupled with the adsorption of simple gases is their projection area when used for surface area determination. The pressure dependence of a projection area is demonstrated for argon at 77 and 87.3 K. A simple model is used to account for the degree of graphitisation of a surface is demonstrated and used to account for the isosteric heat behaviour of non-graphitised carbon blacks. Turning from surfaces to porous solids, an alternative treatment of experiment data (either sub or super critical) is presented that avoids the ambiguity of excess amounts adsorbed. Using this method one is able to obtain pore size distributions and amounts adsorbed without relying on such things as helium expansion volumes. Since this type of method is usually applied to composite solids we also demonstrate the correct method for calculating the heat of adsorption using independent sets of simulations. The final topic covered in this paper is an example of the information that can be gained from the heat capacity of an adsorbed phase.     

LIGHT-SCATTERING STUDY OF POLYELECTROLYTE HOLLOW CAPSULES

Silver halide (AgX) microcrystal was used as template to synthesize hollow polyelectrolyte capsules. These hollow capsules were characterized by laser light scattering (LLS) used to measure the size of the capsules in solution. The ratio of hydrodynamic radius (Rh) from dynamic LLS to the radius of gyration (Rg) from static LLS is almost unity, revealing that the entities are hollow in solution. The results suggest that the LLS method can be regarded as a good complement to the confocal laser scanning microscopy (CLSM) method for the characterization of small hollow capsules, and it possesses the advantage of not needing fluorescence labeling.     

Biocomposites of covalently linked glucose oxidase on carbon nanotubes for glucose biosensor

The formation of covalently linked composites of multi–walled carbon nanotubes (MWCNT) and glucose oxidase (GOD) with high-function density for use as a biosensing interface is described. The reaction intermediates and the final product were characterized by using FT–IR spectroscopy, and the MWCNT-coated GOD nanocomposites were examined by atomic force microscopy (AFM) and transmission electron microscopy (TEM). Interestingly, it was found that the GOD–MWCNT composites are highly water soluble. Electrochemical characterization of the GOD–MWCNT composites that were modified on a glassy carbon electrode shows that the covalently linked GOD retains its bioactivity and can specifically catalyze the oxidation of glucose. The oxidation current shows a linear dependence on the glucose concentration in the solution in the range of 0.5–40 mM with a detection limit of 30 μM and a detection sensitivity of 11.3 μA/mMcm². The present method may provide a way to synthesize MWCNT related composites with other biomolecules and for the construction of enzymatic reaction-based biofuel cells and biosensors. Supported by grants from the National Natural Science Foundation of China (NSFC, No. 20125515; 90206037; 20375016) and the Natural Science Foundation of Jiangsu Province (Grant No. BK 2004210)     

碳糊电极阳极溶出法测定中药甘草中桑色素

用碳糊电极阳极溶出法测定桑色素的含量。在0.15mol·L-1NH4Cl 氨水缓冲溶液的介质中富集120s,桑色素在+0.10V(vs.SCE)左右出现阳极溶出峰。其峰电流的大小与桑色素的浓度呈线性关系。线性范围为4.00×10-6～1.40×10-5mol·L-1,相关系数为0.9996,检出限可达1.00×10-6mol·L-1,回收率为99.87%～102.01%。此法不用汞电极,灵敏度高,操作方便、快捷,成功地用于甘草提取物中桑色素的测定。     

6—磺酰氯香豆素用作发光标记物的初探

过量C6SCl与丙氨酸在pH 9.11(H_3BO_3-NaOH)缓冲体系中,40℃反应40min,经乙酸乙酯萃取分离后,点样在层析聚酰胺膜上,用甲酸+水(1+1)展开,衍生产物得到很好的分离。斑点经1 mol·L~(-1)NaOH喷雾,紫外灯预光照10 min和干燥后,荧光强度与在4～60×10~(-11)mol范围内的丙氨酸量呈良好线性关系。在滤纸基质上,以Pb(AC)_2作重原子微扰剂,标记产物还能产生较强的室温磷光发射。研究表明,C6SCl不仅能作为氨基酸等的荧光标记物,而且可望作为其室温磷光的标记物。     

具有平整表面的定向纳米碳管膜的制备

为了获得表面平整的定向纳米碳管，通过化学及物理的方法将纳米碳管膜进行反转，使其原来的AAO模板底面成为新的表面，用溶液逐步去除表面的铝和氧化铝后，获得了平整的定向纳米碳管膜表面，从而可将其作为工作面使用. 还比较了5％NaOH和6%H₃PO₄＋1.8%H₂CrO₄溶液去除氧化铝的效果.