Effects of Expansion Temperature on Seven kinds of Hoffmann Components in Mainstream Smoke

[Objective]To explore the effect of expansion temperature on the release of seven kinds of Hoffmann components(CO,NNK,NH3,HCN,BaP,crotonaldehyde and phenol)from the mainstream smoke of cigarette.[Method]The release amount of seven kinds of Hoffmann components from the mainstream smoke of cigarettes which were prepared from the cut tobacco treated under different expansion temperatures was determined.[Result]Under the same expansion model,the temperature change produced certain impact on the release amount of NH3,phenol and BAP,while had no significant influence on that of CO,NNK,HCN and crotonaldehyde;under CO2 expansion model,the release amount of seven Hoffmann components was small;the reduction of expansion temperature was good for lowering the harmful index of cigarette to a certain extent.[Conclusion]The study provides basis for optimizing the technical parameters of producing less harmful cigarette.

Strong Tracking Particle Filter Based on the Chi-Square Test for Indoor Positioning

In recent years,a number of wireless indoor positioning(WIP),such as Bluetooth,Wi-Fi,and Ultra-Wideband(UWB)technologies,are emerging.However,the indoor environment is complex and changeable.Walls,pillars,and even pedestrians may block wireless signals and produce non-line-of-sight(NLOS)deviations,resulting in decreased positioning accuracy and the inability to provide people with real-time continuous indoor positioning.This work proposed a strong tracking particle filter based on the chi-square test(SPFC)for indoor positioning.SPFC can fuse indoor wireless signals and the information of the inertial sensing unit(IMU)in the smartphone and detect the NLOS deviation through the chi-square test to avoid the influence of the NLOS deviation on the final positioning result.Simulation experiment results show that the proposed SPFC can reduce the positioning error by 15.1%and 12.3% compared with existing fusion positioning systems in the LOS and NLOS environment.

Degradation Dynamics of Pyrethroids in Cigarette Production Environment

[ Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production, the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied. [ Method ] Three kinds of pyrethroids （permethrin, cyfluthrin and c/s-cypermethrin） were adminis- trated to two media （cut tobacco and iron sheet surface） in cigarette production environment at MRLs concentration, and the first sampling was conducted at 24 d post administration. Afterwards, sampling was performed once every 7 d, with a total of six times. The degradation rates of insecticides in different media were cal- culated, and degradation models were established. [ Result ] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time, and degradation rates presented the trend of fast-slow-fast ; the degradation rates of permethrin, cyfluthrin and c/s-cypermethrin in cut tobacco at 36 d post ad- ministration were 97.14%, 88.89% and 95.38%, respectively; the degradation rates on iron sheet surface were 29.95%, 48.99% and 40. 24%, respectively. The half lives of three kinds of insecticides in cut tobacco were 1 -2 d, while those on iron sheet surface were 6 - 10 d. [ Conclusion] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time, and their degradation regularity accorded with first order kinetic equation.