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41.
硕士研究生毕业论文评阅及其分析 总被引:1,自引:0,他引:1
通过对硕士研究生毕业论文进行客观评估,指出了研究生论文中表现出的一些共性问题,在此基础上提出了进一步提高研究生培养质量的若干建议。 相似文献
42.
本文介绍了I/O映照记忆模型自学习控制的理论和方法,并用其为具有重大节能意义的泵类、风类机类等交流调速装置设计通用的智能控制器,以实现对期望转速的跟踪控制.文中给出了统一的系统模型描述、学习控制原理及初值控制的处理方法. 相似文献
43.
For the major, minor and trace element analysis of the inorganic compounds of a Ruhr-Saar coal different preparation techniques are investigated with X-ray fluorescence analysis, electron microprobe and classical wet chemical methods minimizing sample weight at standard preparation times and analytical accuracies. Considering accuracy as well as preparation efforts, determinations by electron microprobe on small sample amounts (<50 mg) proved to be superior to the other methods.Abbreviations AAS
atomic absorbtion spectrometry
- EMA
electron microprobe analysis
- IC
ion chromatography
- ISE
ion sensitive electrode
- PHOT
photometry
- WCA
wet chemical analysis
- XRF
X-ray fluorescence analysis
- LTA
low temperature plasma ashing
- HTA
high temperature ashing
- l.o.i.
loss on ignition 相似文献
44.
Summary Based on a thorough knowledge of the actual system precision significance testing of the primary eigen values, resulting from principal component analysis of the two-dimensional data array of HPLC with photodiode-array detection, is a powerful means to uncover unresolved chromatographic peaks. The implementation of this chemometric technique for assuring peak homogeneity and results showing the efficiency for two-component peaks in regard to spectral characteristics, chromatographic resolution and absorbance ratio of the investigated compounds are presented. 相似文献
45.
The strategy to identify cadmium deactivation mechanism in Arabidopsis thaliana has been developed using selective and sensitive hyphenated techniques. Cadmium concentrations, in main parts of the plant, were determined by ICP-MS and total amount was found as 0.43-0.44 μg g−1 in leaves and 3.3-3.4 μg g−1 in roots. Speciation of the metal complexes in cells was investigated by SEC-ICP-MS in order to estimate the accumulation process. Phytochelatins, desglycyl-phytochelatins and phytochelatins homologues lacking the N-terminal γ-linked glutamic acid were extracted from plant and were identified by RPLC-ESI-MS. Two-dimensional chromatography allowed to link the metal complexes separated by SEC with isoforms of phytochelatins analyzed by high resolution RPLC and confirm their significant responsibility for metal accumulation. The potential of the cadmium complexes speciation indicates that obtained results could be reliable source of knowledge to confirm the information coming from the well-known genomic sequence of Arabidopsis and to estimate the role of γ-glutamyl transpeptidase in metabolism of glutathione. 相似文献
46.
Sample preparation in analysis of pharmaceuticals 总被引:1,自引:0,他引:1
Dragana Mutavdi Pavlovi Sandra Babi Alka J.M. Horvat Marija Katelan-Macan 《Trends in analytical chemistry : TRAC》2007,26(11):1062-1075
Sample preparation is a very important and essential step in environmental analysis. This article presents an overview of extraction methods for environmental samples, focusing especially on pharmaceuticals as there is great concern about them as pollutants. 相似文献
47.
张德礼 《中国科学B辑(英文版)》1991,(8)
In this paper, superhigh reproductive rate strains of MEV with titre more than HA8192* or TCID50 log9.7 10 have been achieved both by cultivation in cell lines with different susceptibility to MEV and by isolating and identifying in field by the author. The systematic tests proved that S18 and L12 strains of MEV are the best strains for vaccine preparation. In this study, the best means for the tissue cultivation of MEV and the most advanced technological process for the production and detection of serum-free cell-cultured MEV fluids with super-high HA titre in batches in large quantities have been established for the first time. Optimum conditions for MEV inactivation were determined, and safe and effective inactivated vaccines with mineral oil or A1(OH)3 gel adjuvant were successfully prepared with serum-free cell-cultured MEV fluids. Both vaccines with different adjuvants can be manufactured in batches in large quantities and have been widely used all over China since 1986. The change laws of the imm 相似文献
48.
Capillary electrophoresis coupled to time of flight-mass spectrometry of therapeutic peptide hormones 总被引:2,自引:0,他引:2
We have established a method for separation and characterization of a series of peptide hormones of pharmaceutical interest and wide therapeutical use by capillary electrophoresis-electrospray-mass spectrometry (CE-ES-MS) using a sheath flow interface. Several parameters were systematically investigated, such as concentration of the electrolyte, organic solvent and sheath liquid composition, gas flow rates and capillary position. Moreover, limits of detection, linearity, repeatability and day-to-day reproducibility of the proposed method were studied in order to obtain the main quality parameters. 相似文献
49.
The composition of volatile compounds produced by fruit during growth and post-harvest storage and ripening has been studied and the different headspace methods compared. Static and dynamic headspace sampling have been compared and evaluated according to their capacity to collect and concentrate volatiles from the atmosphere surrounding the fruits, and FID, MSD, and organoleptic detection have been compared. The results emphasize that the headspace sampling procedure selected is crucial to the performance of subsequent analysis. 相似文献
50.
Rafael Lucena 《Analytica chimica acta》2004,509(1):47-54
A multipurpose chamber capable of implementing a variety of continuous separation techniques is reported. The proposed module can be used in conjunction with flow manifolds coupled on-line to optical detectors in order to develop simple autoanalyzers for full sample pretreatment. The analytical applicability of such a device is discussed with specific regard to gas diffusion, dialysis, solid-phase extraction (SPE), and precipitation/dissolution techniques. Its versatility and simplicity are among the main advantages. Four different automated analyzers based on the use of the multipurpose chamber have been developed for monitoring of different quality control parameters of liquid food samples, namely, carbon dioxide in beer, ascorbic acid in fruit juice, caffeine in soft drinks and lactose, fat and protein in milk. The results obtained were compared with those provided by the existing alternatives for the same applications in terms of sensitivity and precision. 相似文献