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41.
42.
Two published procedures for glass capillary column production are applied to produce capillaries for chromatography of polar natural compounds. Soda lime glass capillaries, after leaching with aqueous HCL, are either treated with colloidal silicic acid or with barium carbonate and coated with either Silar 7CP or SE 52. A test mixture as well as polar carbohydrate and peptide mixtures are chromatographed on the different columns and their chromatographic properties are evaluated. Combined capillary gas chromatography-electron impact and chemical ionization mass spectrometry are used for identification of the peptide sequence. 相似文献
43.
M. -L. Tan Y. H. Qian I. Goldhirsch S. A. Orszag 《Journal of statistical physics》1995,81(1-2):87-103
Many continuum theories for granular flow produce an equation of motion for the fluctuating kinetic energy density (granular temperature) that accounts for the energy lost in inelastic collisions. Apart from the presence of an extra dissipative term, this equation is very similar in form to the usual temperature equation in hydrodynamics. It is shown how a lattice-kinetic model based on the Bhatnagar-Gross-Krook (BGK) equation that was previously derived for a miscible two-component fluid may be modified to model the continuum equations for granular flow. This is done by noting that the variable corresponding to the concentration of one species follows an equation that is essentially analogous to the granular temperature equation. A simulation of an unforced granular fluid using the modified model reproduces the phenomenon of clustering instability, namely the spontaneous agglomeration of particles into dense clusters, which occurs generically in all granular flows. The success of the continuum theory in capturing the gross features of this basic phenomenon is discussed. Some shear flow simulations are also presented. 相似文献
44.
Joël Delville 《Applied Scientific Research》1994,53(3-4):263-281
Experiments are performed in an incompressible plane turbulent mixing layer, using various hot wire rake configurations. From these experiments, the Proper Orthogonal Decomposition is applied for kernels where the space-time correlation tensor is evaluated over different spatial meshes and velocity components configurations. The resulting decompositions are then discussed in terms of characterization of the organization of the flow for various scalar or vectorial approaches of the POD. An incrtial range law is evidenced. The instantaneous contribution of the first modes of the POD to the organization of the flow is analyzed. A dynamical behavior for the organization of the flow is observed from the correlation between the first two modes contribution. 相似文献
45.
Some polymer melts (of high viscosity ) can wet completely the surface of a non miscible, simple liquid. We discuss here the laws of spreading for a macroscopic droplet of this type, when the internal friction of the droplet dominates. We predict a droplet radius increasing liket
1/4 wheret is the spreading time, or equivalently a droplet curvature decreasing liket
–1. The droplet should be surrounded by a precursor film, which is not discussed in the present note. 相似文献
46.
在一个石英反应室内,让激光解离的Ni^+与连续喷入的酯类化合物分子束流反应,生成的产物离子经飞行时间质谱仪检测,研究了Ni^+与乙酸乙酯、乙酸丙烯酯、乙酸乙烯酯、乙酸丁酯的气相反应。根据如下机理满意的解释了发生的反应:(1)Ni^+与酯形成激发态络合物;(2)β-H迁移至烃氧基的氧上形成Ni^+的双配体化合物离子;(3)失去一中性配体分子得Ni^+的单配体化合物离子。由酯的ΔH离和D(Ni^+-A 相似文献
47.
High-quality online course materials were reconstructed through feedback from undergraduate students and online data analysis regarding constructed learning materials on the Chao Xing Learning Platform. They were used for studying organic chemistry courses online and offline in university for nationalities. This model, based on student-centered teaching, can effectively transform students from passively accepting knowledge to actively learning and internalizing knowledge. This strategy can also enhance the students' learning initiative and the effects of learning, and hopefully be helpful to the universities in multi-ethnic areas in developing fundamental disciplined construction of organic chemistry and other courses. 相似文献
48.
一种新型的表面声波阻抗传感器及其在液相体系中的应用姚守拙,陈康,刘德忠,聂利华(湖南大学化学化工系,长沙,410082)关键词表面声波,阻抗传感器,液相应用表面声波传感器(SAWS)具有较高的灵敏度和检测精度,已广泛应用于气体微量组分分析、色谱检测和... 相似文献
49.
分形理论及其在高分子科学中的应用 总被引:6,自引:0,他引:6
介绍了分形的基本概念,分形维数的定义及计算方法,讨论了近年来分形理论在高分子科学研究方面的一些应用,内容主要包括高分子溶液、高分子材料的磨损,断裂及界面,高分子结晶过程、导电高分子等。 相似文献
50.
In this review, we summarize the number of scientific publications in the field of FP/FA sensor in recent five years, and introduce the recent progress of FP/FA sensor based on nanomaterial. The various analytical applications of FP/FA sensor based on nanomaterial are discussed. We also provide perspectives on the current challenges and future prospects in the promising field. 相似文献