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61.
T. Cserháti 《Biomedical chromatography : BMC》2009,23(2):111-118
The newest results in the employment of carbon‐based composites in various chromatographic techniques such as gas–liquid chromatography, high‐performance liquid chromatography and electrically driven separation techniques for the separation, quantitative determination and identification of a wide variety of compounds in complicated matrices are compiled. The results are concisely described and critically evaluated. The future trends in the application of carbon‐based compounds in the chromatographic separation methods are briefly discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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在金属层表面引入微结构以实现对Z箍缩等离子体形成和发展过程中不稳定性的调控具有重要研究价值.在“强光一号”装置上(峰值电流~1.4 MA,上升时间~100 ns),开展了针对具有一维周期性凹槽调制结构的金属薄膜的电爆炸实验研究.实验负载采用外推型平面结构,基底为30μm厚铝膜,刻蚀周期为2 mm,刻蚀深度约为10μm.通过激光阴影成像、激光干涉成像和可见光自辐射成像等系统进行联合诊断.实验结果表明刻蚀结构对等离子体发展过程的不稳定性特征产生了明显调制作用,原本征波长也受到抑制,微结构周期对不稳定结构波长产生趋同效应;未刻蚀一侧边界层同样受刻蚀层结构的影响,在不稳定结构上表现出相似形貌,且内外侧不稳定性特征的耦合关联性增强;刻蚀凹槽处在爆炸过程中膨胀更为迅速,形成的表面等离子体结构与初始结构反相;在刻蚀结构的几何突变处会形成细长的等离子体喷流,在二分之一刻蚀波长处出现波谱特征峰.理论分析表明电流密度调制造成电热不稳定性分布改变是调控作用产生的重要原因. 相似文献
64.
Q.G. Meng H.Y. Fang J.G. Yang S.D. Ji 《Theoretical and Applied Fracture Mechanics》2005,44(2):178-186
By analyzing the shape of twin wire welding’s arcs and the track of droplets’ transition, the phenomenon that the twin wire welding’s fore arc and rear arc all deflect to the middle of the two arcs is found. Based on this the double ellipsoid heat source model is amended, and a heat source model which can apply to calculate the twin wire welding’s temperature field is put forward. This model is testified by actual experiment of temperature sampling. By comparing the temperature field of twin wire welding and single wire welding, the results show that twin wire welding has slender weld pool the end part of which is ellipsoid, and its HAZ is narrower than that of single wire welding. So, twin wire welding can not only reduce the Al alloy generating hot crack, but can also weaken the “overaging” softened phenomenon of heat treated strengthening Al alloy. In the end, the evolving rules of 2219 Al alloy’s longitudinal and transverse stress when welded with twin wire welding are analyzed. 相似文献
65.
Wear-resistant coatings were prepared on the surface of the Q235 low-carbon steel plate by HVAS with the carbonitride alloying self-shielded flux-cored wire. Detection and analysis on the microstructure and properties of the coatings were carried out by using scanning electron microscope, microhardness tester and wear tester. The forming, the wear resistance and its mechanism of the coatings were studied. The results show that the coatings have good forming, homogeneous microstructure and compact structure. The coatings have good hardness, the average microhardness value reaches 520 HV0.1, and the highest value is up to about 560 HV0.1. As a result, the coatings have good abrasive wear performance and adhesion strength. 相似文献
66.
An electrically heated microelectrode chip (HMEC) was designed and the Ru(bpy)32+/carbofuran electrochemiluminescence (ECL) systems were applied to characterize the performance of the HMEC. The ECL intensities increase at elevated electrode temperature, and the detection limit at 60°C (electrode surface temperature) was about 10 times lower than that at 30°C. The results indicate that new heated electrode can be handled easily and can be mass produced, the difference between the electrodes was little. The stability of the HMEC was good since the electrode surface can hardly be destroyed during detection and storage. 相似文献
67.
We discuss theoretically the transport of a light pulse along a quantum wire made of a nonlinear ionic crystal. Under the adiabatic approximation, the propagation of the axial component of the electric field along the quantum wire has soliton properties and its distribution in the cross section of the quantum wire still approximately satisfies the Bessel equation. The size effect of the quantum wire on the dispersion relation of the polaritons is also discussed. 相似文献
68.
本文介绍在分子束外延系统中,沿[311]面原位生长GaAs/AIAs量子线结构的一种简单方法及其拉曼和发光特性。这一方法能克服目前纳米尺度光刻技术的困难,因此,是一种制备低维样品的有希望的方法。 相似文献
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