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Shujuan Li

Publications and source records attributed to Shujuan Li.

2 recordsLinked to original sources

[Current situation and some intending problems of landscape spatial dynamic model].

Along with the rapid development of remote sensing, geographic information system, computer and other supporting technologies, model approach has become the major method of landscape dynamic study. Based on literature review, this paper analyzed the current situation and some intending problems of the development of landscape spatial dynamic model. Three kinds of models, i. e., stochastic landscape model, neighborhood rule model and landscape process model (including percolation model, individual-based landscape model and spatial ecosystem model) were mainly introduced, and their development status, existing problems and related improvement work were analyzed. The development of model test technologies, such as verification analysis, validation analysis, and sensitivity analysis, were also analyzed. Finally, this paper summed up six major problems that should be dealt with in the future development of the landscape spatial dynamic models. These problems included model arithmetic optimization, scale conversion, model complication and predigesting, model test and assessment, bringing forward of general model, and integration of the traditional model with social-economic factors.

Algorithms↗

[Simultaneous determination of the residues of pyrethriods, organochlorines and polychlorinated biphenyl congeners in unpolished rice by gas chromatography with gel permeation chromatography purification].

The separation behaviors of organochlorine pesticides, pyrethriod pesticides, polychlorinated biphenyl congeners (PCBs) and unpolished rice matrixes were systematically investigated with gel permeation chromatography (GPC) because of its outstanding capability in removing lipid and pigments from sample solutions. A separation method was proposed for the quantitative determination of 35 pesticides and PCBs in unpolished rice by GPC and gas chromatography simultaneously. Samples were extracted with ethyl acetate, purified by GPC, and then determined by gas chromatography and electron capture detection (GC-ECD). With external standard method, the recoveries of 3 standard addition levels of low, medium, high concentrations were 70.1% - 107.4%, 70.3% - 109.9%, 70.8% - 109.5%, respectively with relative standard deviations from 2.3% to 13.3%. The detection limits were 0.07 microg/kg for organochlorines and PCBs, and 0.44 microg/kg for pyrethriods.

Chromatography, Gas↗