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To understand the epidemic status of human intestinal parasitic diseases and evaluate the effect of the control program in Nanping City, so as to provide an evidence for improving the disease control.The villages were selected by the stratified cluster sampling method and the residents in these villages were surveyed for human intestinal parasitic diseases, and kindergartens were also selected and the children in these kindergartens were surveyed forIn 2007, before the control program, 9 851 residents of Nanping City were surveyed, with the parasitic infection rate of 9.10% (896 infection cases), and the infection rate ofThe infection situation of human intestinal parasites is decreased after the implementation of the control program but the infection rate is still at a high level, and the control work should be strengthened.［

The 60Co γ-ray radiation induced polymerization of butadiene in bulk and in ethanol at temperature ranging from 15 to 45°C has been studied. Hydrogen peroxide was used as initiator in some occasions. The mechanisms of polymerization in ethanol seems to fit the no-energy transfer kinetics described by Chapiro (1962) and the ratio of relative rate of free radical production of solvent/monomer Φrel is 19. When hydrogen peroxide was added to the butadiene-ethanol system the polymerization rate increased and hydroxyl terminated polybutadiene was obtained. The microstructure of polybutadiene was studied by IR and NMR spectra.

This paper reports a study of a polymer sequence, and the striking changes with stereochemical configuration in polymethyl methacrylate (PMMA) by radiation-induced polymerization. The polymer structure was investigated by means of 13 C NMR spectroscopy, showing that carbon-13 spectra were interpreted in terms of pentad sequences for the CO resonance; the spectrum reveals seven separate resonance lines, which can be assigned to the ten possible pentads. Comparison of the observed and calculated intensities of the assigned resonances indicated that the Bernoullian statistic describes the radiation-induced polymerization mechanism of the PMMA sample under study. The experimental results show the radiation induced dose and the probabilities of isotactic, syndiotactic and heterotactic triads are a function of P m , respectively. The preference of the propagation or degradation for the syndiotactic in PMMA can be found due to the activation enthalpy and dependence of radiation dose. The difference in the free activation enthalpies is from 923 cal/mol to 773 cal/mol with higher activation entropy in the growth step. Molecular weights of PMMA by various radiation dose in polymerization were determined by GPC. The authors have estimated the N -ads distinction equation, and by using this distinction equation satisfactory results have been obtained. The Bernoullian process can then be distinguished.