Study on Absorptive Capacity to Formaldehyde and Physiological and Biochemical Changes of Scindapsus aureus Based on the Regulation of LaCl_3

[Objective] This study was to analyze LaCl3 sprayed onto Scindapsus au- reus on Chlorophyll content and plasmamembrane permeability of leaves of Scindap- sus aureus, in order to determinate a suitable dosage of LaCl3. [Method] With Scindapsus aureus as the test subject, 110 households of 20 communities in the New District of Nantong were selected to investigate formaldehyde concentration in indoor air; and effect of LaCl3 on absorptive capacity to formaldehyde of Scindapsus aureus was studied through fumigating in laboratory. Simultaneously, its physiological and biochemical mechanism of formaldehyde resistance was studied. [Result] The re- sults showed that formaldehyde pollution of indoor air was serious in the New District of Nantong, and the degree of pollution was related to the time after decoration. The suitable concentration of LaCl3 for Scindapsus aureus was 20 mg/L. The ability to ab- sorb formaldehyde of Scindapsus aureus, which was calculated by per unit leaf area, was enhanced after spraying the suitable concentration of LaCl3 by 19.75%. When Scindapsus aureus was stressed by formaldehyde, chlorophyll content decreased by 39.87%, membrane permeability and cumulative MDA amount increased by 8.17% and 56.92%, respectively, and POD activity increased by 11.32%. However, by com- paring the group pre-sprayed with LaCl3 and the group not sprayed with LaCl3 under formaldehyde stress, chlorophyll content of Scindapsus aureus reduced lessly, mem- brane permeability and MDA both increased lessly, while POD activity increased more. [Conclusion] This study provides a new thinking direction for broadening of rare earth application and control measures of indoor air pollution.

Slow driving control of tracked vehicles with automated mechanical transmission based on fuzzy logic

In order to move tracked vehicles at an extremely slowspeed with automated mechanical transmission（ AMT）,slowdriving function was added in the original system. The principle and requirement of slowdriving function were analyzed. Based on analysis of slow driving characteristic,identification of slowdriving condition and fuzzy control algorithm,a control strategy of the clutch was designed. In order to realize slowdriving,the clutch was controlled in a slipping mode as manual driving. The vehicle speed was increased to a required speed and kept in a small range by engaging or disengaging the clutch to the approximate half engagement point. Based on the control strategy,a control software was designed and tested on a tracked vehicle with AMT. The test results showthat the control of the clutch with the slowdriving function was smoother than that with original systemand the vehicle speed was slower and steadier.