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51.
52.
J. Martinez Salazar R. K. Bayer T. A. Ezquerra F. J. Baltá Calleja 《Colloid and polymer science》1989,267(5):409-413
The morphology and structure of high molecular weight linear polyethylene (M
w 450000) filled with carbon black and processed using molds that introduce an elongational flow component during injection molding has been examined using electron microscopy and x-ray diffraction techniques. The study of fracture surfaces reveals the display of shish-kebabs oriented along the injection direction with segregated longitudinal channels of carbon black particles. Molecular and lamellar changes in orientation are, furthermore, studied across the thickness of the moldings. It is shown that addition of carbon black particles to injection-molded polyethylene induces significant changes in lamellar orientation. Thus, while lamellar overgrowth proceeds perpendicular to the fiber axes within carbon free channels, lamellae grow randomly within carbon-enriched regions where flow is less pronounced. 相似文献
53.
蒙脱石修饰碳糊电极测定氨基酸的研究:Ⅱ.酪氨酸的测定 总被引:13,自引:1,他引:13
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。 相似文献
54.
二氧化碳多相催化加氢的新进展 总被引:4,自引:0,他引:4
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。 相似文献
55.
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... 相似文献
56.
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. 相似文献
57.
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) 相似文献
58.
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。 相似文献
59.
60.
《Electroanalysis》2004,16(12):994-1001
The interfacial behavior of electrodes fabricated from carbon film resistors of 2 and 20 Ω in supporting electrolyte solutions of varying pH used in electroanalytical experiments has been characterized by electrochemical impedance spectroscopy with complementary cyclic voltammetric experiments. Equivalent circuits are proposed to fit the experimental data and the influence of electrode pretreatment has also been investigated. 相似文献