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11.
脂肪乳剂Intralipid代谢产物的高效液相色谱测定   总被引:2,自引:0,他引:2  
夏立钧  吴海福 《分析化学》1994,22(8):759-762
本文介绍了利用HPLC色谱柱前衍生化技术简便,正确和灵敏地测定血清中游离脂肪酸的方法。在最佳条件下,一些脂肪酸的最低检知量为0.04μg。方法已用于脂肪乳剂Intralipid在诱发急性坏死性胰腺炎动物体内代谢产物测定。  相似文献   
12.
In this paper, based on the Hirota bilinear method and symbolic computation approach, multiple-order rogue waves of (2+1)-dimensional Boussinesq type equation are constructed. The reduced bilinear form of the equation is deduced by the transformation of variables. Three kinds of rogue wave solutions are derived by means of bilinear equation. The maximum and minimum values of the first-order rogue wave solution are given at a specific moment. Furthermore, the second-order and third-order rogue waves are explicitly derived. The dynamic characteristics of three kinds of rogue wave solutions are shown by three-dimensional plot.  相似文献   
13.
为了研究光束相干合成中偏振态的特性,取理想矩形光束进行模拟分析。通过改变偏振态的退偏率、偏振态夹角、参与合成的子束数目等,观察光场在远场叠加的合成效果。讨论了这些因素对远场合成效果的光强分布、峰值功率密度、光束质量因子等的影响。模拟结果显示:当退偏率小于10%、偏振态夹角小于18时,合成后光束质量因子小于1.1。  相似文献   
14.
The spectral radiation characteristic of a non-luminous flame is analyzed. The apparatus and the calibration procedure based on infrared emission spectrometry for measurements of the flame are introduced.The influence of background radiation and stray light on the measurement results could be reduced and suppressed by the design of thermolator and digital lock-in technique. A blackbody cavity was used as reference emission source to calibrate the system that completed absolute measurement. The spectral measurement range is 1-20 μm. The least measuring distance and the lowest power detected at the entrance pupil are 550 mm and 10-9 W/cm2, respectively. The experimental results show that the measure error is less than 10%.  相似文献   
15.
Mekhankov and Fedyanin have obtained two soliton solutions for the non-linear S3 equation. We now find a set of new solutions of the same equation, which includes solutions of plane wave, amplitude modulation, quasi-soliton and soliton type.  相似文献   
16.
The distribution of variants and three-dimensional (3D) configurations of the heterogeneously formed S (Al2CuMg) precipitates at dislocations, grain boundaries and the Al20Cu2Mn3 dispersoid/Al interfaces were studied in this research. By means of high resolution transmission electron microscopy, we systematically investigated the orientation relationships (ORs) between these heterogeneously formed S precipitates and the Al matrix, and further unraveled that the preferred orientation of S variants at grain boundaries and at dispersoid/Al interfaces are respectively associated with the OR between the precipitate habit plane and the grain boundary plane, and the OR between the precipitate habit plane and the interface plane. The inherent characteristic of the crystal structure of the S phase, i.e. the symmetry of the pentagonal subunit, was considered to be the fundamental factor determining the preference of the variant pair. By using high angle annular dark field scanning transmission electron microscopy tomography, we successively obtained the 3D reconstruction of the S precipitates at these defects. Both the morphology of an individual S precipitate and the overall configuration of the S precipitates nucleated at these defects can be clearly observed without misunderstandings induced by the overlap and projection effects of the conventional two-dimensional methods.  相似文献   
17.
In this paper, the compatibility between the gauge transformations and the additional symmetry of the constrained discrete Kadomtsev-Petviashvili hierarchy is given, which preserves the form of the additional symmetry of the cdKP hierarchy, up to shifting of the corresponding additional flows by ordinary time flows.  相似文献   
18.
Let l be a given nonzero integer.The authors give an explicit characterization of the positive integer k that makes the Diophantine equation x2-kxy+y2+lx=0 have infinitely many positive integer solutions(x,y).  相似文献   
19.
In this study, rice husk, an abundant agricultural byproduct, was utilized as an alternative silica source for the synthesis of MCM-22. The zeolite with high crystalline was synthesized using a three-stage varying-temperature hydrothermal method. The prepared silica and MCM-22 were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the duration required for zeolite crystallization was significantly decreased under varying-temperature conditions. The MCM-22 was in the form of thin platelet-like crystals, and no amorphous material existed in the framework of the MCM-22 after calcination and ammonium exchange. Cationic brilliant red 5GN, a basic dye used in the wool and blanket factories for fiber dyeing, was selected as the adsorptive to study the adsorption performance of the MCM-22. Adsorption experiments indicated that the maximum extent of adsorption was obtained at pH of 10, contact time of 60 min, and MCM-22 dose of 1.0 g/L. The adsorption kinetic has been described by first-order and pseudo-second-order models. It was observed that the rate of dye adsorption followed pseudo-second-order model.  相似文献   
20.
中学化学教师新课标培训前的调查分析与对策   总被引:2,自引:2,他引:0  
曾懋华 《化学教育》2005,26(2):45-47
为了迎接大规模的中学化学教师新课标培训,探索新课标培训的新思路和新方法,根据现代教育发展的需要,通过对粤北山区中学化学教师新课标培训前的现状进行调查与分析,对中学化学教师新课标培训的模式、存在的问题、解决方法等内容作了比较全面的探讨,提出了相应的对策。  相似文献   
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