High-speed tray seedling transplanting robot was developed which used two-DOF parallel mechanism as transplanting mechanism, and pneumatic manipulator as the end-effector, so it can achieve high speed of transplanting. According to transplanting seedlings from high-density plug to the low-density plug, a type of transplanting path was put forward which consists of rise, translation and decline, in this paper, it was called three-stage trajectory. Analysis the movement characteristic of each stage, make sure the stability of transplanting, then the sine motion law, quintic polynomial motion law and septic polynomial motion law were put forward as the Transplanting movement function according the analysis of movement characteristic. Compared the transplanting efficiency and stability of the three motion law through their velocity, acceleration and saltus, finally, quintic polynomial motion law was preferred as transplanting robot motion law. Transplanting experiment was taken on the developed prototype, the transplanting frequency was more than 60 per minute and the qualified rate can reach 92.71%.
A new magnetic plate-type precision seeding production line and its control system were designed based on the magnetic seed-metering principle. The control system is consisted of DVP-40ES Programmable Logic Controller and LJD-51-XB+ Mico Controller Unit. The PLC control system controls the working flow of the production line. The MCU control system controls turnover movement of the sowing board and up-and-down movement of the seed case for whole tray seed-filling and sowing. Seeding tests for the magnetic powder coated rape seeds showed that the rate of single-seeding, over-seeding and miss-seeding were 90.2778%, 4.6875% and 5.0347% respectively. The seeding speed was 257 trays per hour, an average of each tray with 14s. It meets the requirements of precision seeding. The system design is reasonable and reliable.
Yeast two-hybrid system was used to investigate the estrogenic activities of 13 kinds of representative endocrine disrupting chemicals (EDCs) and their combinary effects. Results show that the order of estrogenic potencies for these chemicals is: 17α-ethynylestradiol>diethylstilbestrol >17β-estradiol>estrone>estriol>branchedp-nonylphenol>4-t-octylphenol>bisphenol A>diethyl phthalate>4-n-nonylphenol>di-(2-ethylhexyl) phthalate>dibutyl phthalate>dimethyl phthalate. The mixture effects of multiple EDCs were compared to those obtained from individual chemicals, using the model of concentration addition. Results reveal that the estrogenicities of multicomponent mixtures of more than three (including three) of EDCs follow antagonistic effects, while there is no definite conclusion for binary systems. The less than additive effects were also confirmed in the spiked experiments conducted in the extracts of real water samples.
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