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The safe storage and protection of grain includes the exploitation of plant-based fumigants as a green control technology. This study first determined the fumigant toxicity of 12 traditional Chinese medicinal plants against adults of the rusty grain beetle, Cryptolestes ferrugineus (Stephens), one of the most ubiquitous and pestilent grain storage pests worldwide. Exposure to volatiles released from Illicium verum Hook. f. powder was found to be by far the most lethal. Illicium verum power and its volatiles eluent were then confirmed to be highly effective in killing both larvae and adults of C. ferrugineus. Star anise volatiles also showed good biological activity against Lasioderma serricorne (Fabricius) and Sitophilus zeamais Motschulsky, but not Tribolium castaneum Herbst. No significant differences were found in mortality of the adults of the rusty grain beetle when exposed at different temperatures ranging from 15−35°C. Gas chromatography-mass spectrometry (GC–MS) analysis showed that the main components of the eluent of star anise powder were trans-anethole (62.60%), estragole (23.70%), linalool (3.66%) and d-limonene (2.15%). In the fumigation test using synthetic standards of these four chemicals, only trans-anethole showed effective biological activity with exposure to 30 mL/L trans-anethole for 24 h resulting in 100% mortality of rusty grain beetle adults. Estragole did significantly enhance fumigant efficiency of trans-anethole. We further found that trans-anethole affects the beetles acetylcholinesterase activity, which was inhibited and decreased by 64.48% within 24 h. The results therefore show that trans-anethole, the major component of star anise volatiles contributes to its fumigant toxicity against C. ferrugineus by, at least partly, affecting its insect nervous system. Hence, star anise or its biologically active substances show very good potential to be used as a botanical insecticide to control C. ferrugineus.

Taking the auxiliary shaft proposed by Ruihai Mining Co., Ltd. as the research object, in order to study the load law of shaft lining and ingate under high stress fluid solid coupling in deep bedrock and the influence of different permeability coefficient on the stability of shaft lining and ingate surrounding rock, Midas software was used for numerical simulation analysis, and the results show that:( 1) After the shaft excavation, the pore water pressure of surrounding rock around the shaft wall and ingate decreases gradually, which is the main permeable area. After the support, the pore water pressure is obviously raised, and the water isolation effect of the supporting layer is obvious. (2) After the shaft excavation, the area near the arc surface of shaft wall tangent to Y direction shows high compressive stress, and the maximum principal stress at - 1277.5m depth is more than 150MPa. When the polar angle increases from 0 to 180 °, the maximum principal stress increases first and then decreases. (3) After the excavation of ingate, the bottom corner and arch top are stress concentration areas before and after support. ( 4) Under the action of three different permeability coefficients, the influence of permeability coefficient on pore water pressure and maximum principal stress can be ignored after supporting measures are taken. The research results provide important theoretical basis for auxiliary shaft construction design.

Elastic scattering of 10Be on a 208Pb target was measured at = 127 MeV, which corresponds to three times the Coulomb barrier. The secondary 10Be beam was produced at the Radioactive Ion Beam Line in Lanzhou of the Heavy-Ion Research Facility in Lanzhou. The angular distribution of elastic scattering in the 10Be + 208Pb system shows a typical Fresnel diffraction peak. Optical model analysis of the angular distribution was performed using the Woods-Saxon, double-folding and global potentials. With the global potential, different density distributions were used. The results indicate that different density distributions for the projectile induce distinct effects in the angular distribution.

A Neutron Time-Of-Flight (NTOF) spectrometer based on Heavy Ion Research Facility in Lanzhou (HIRFL) is developed for studies of neutron production of proton induced spallation reactions related to the ADS project. After the presentation of comparisons between calculated spallation neutron production double-differential cross sections and the available experimental one, a detailed description of NTOF spectrometer is given. Test beam results show that the spectrometer works well and data analysis procedures are established. The comparisons of the test beam neutron spectra with those of GEANT4 simulations are presented., Comment: 9 pages, 7 figures