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Objective: To solve the technical problems in the design and analysis of the core parts of the mold open-closing mechanism related rod. Methods: The motion and force analysis of mold open-closing mechanism with an electric eight-bar was described in detail by using the analytical method. Results： Based on the example calculation, the relationship curve between the displacement of the slider and the crank angle was obtained, and the variation law of velocity and acceleration was further deduced. Meanwhile, the theoretical clamping force, the changing trend and the characteristics of each member force in the sheet extrusion process were analyzed. Conclusion: The method solves the implemented analysis of the electric eight-bar linkage mechanism without the need for professional software, shortening the design and prototyping cycles.

In view of the fact that there were as many as 10 to 13 layers of limestone in Taiyuan formation in Huainan and Huaibei Coalfield, the target strata of ground regional treatment was not unique, the 18413 working face in the west 4th mining area of Pan'er coal mine was taken as an example, the optimization of the target strata was studied. The requirement of water inrush coefficient was the prerequisite for optimum selection of target strata, which determined the selection range of target strata. With C3 6 limestone as the target strata, the water inrush coefficient is less than the critical value after calculation. Therefore, it is inferred that C3 6-C3 12 limestone is the potential target strata. Influencing factors such as hydrodynamic conditions, aquifer hydraulic connection, water-conducting geological structure, limestone spacing, limestone thickness and stratum injectability were the key indicators for optimum selection of target strata. However, the target strata determined by single factor analysis is incompatible with each other, which makes it difficult to achieve the optimal selection of the target strata. Therefore, the analytic hierarchy process was adopted for the optimal selection of the target strata. The optimum selection of target strata of ground regional treatment was taken as the objective layer, hydrodynamic conditions, hydraulic connection between aquifers, water-conducting geological structure, limestone spacing, limestone thickness and stratum injectability were taken as the criterion layer, and C3 6, C3 7, C3 8, C3 9, C3 10, C3 11, C3 12 limestone of Taiyuan formation were taken as the scheme layer, the analytic hierarchy process model was established. The judgment matrix of the target layer and the criterion layer, the criterion layer and the scheme layer were constructed, and the weight of each index of the criterion layer and the single factor score of each scheme of the scheme layer were calculated. The CR values were all less than 0.10 after inspection, and judgment matrices had satisfactory consistency, meeting the consistency test. The total score of each scheme was 0.177, 0.169, 0.170, 0.214, 0.103, 0.114 and 0.053, respectively, which were calculated by the hierarchy total sort. The total score of C3 9 limestone was the largest, indicating that the optimal target stratum of ground regional treatment was C3 9 limestone. The analytic hierarchy process was applied to the study on the optimum selection of target strata of ground regional treatment, and the qualitative problem was transformed into a quantitative problem, realizing the multi-factor quantitative optimum selection of target strata, and providing a new method for optimum selection of target strata.

The disintegration of nanoparticles and drug release are important and imperative for nanoparticle formulations of therapeutic agents. However, quantitatively monitoring the drug release of nanomedicines is a major challenge. In this work, boron-dipyrromethene (BDP) was applied as a model drug to study the disassembly of nanoparticles and drug release. BDP dimers with disulfide and ester bonds were synthesized, and their nanoparticles were made. The accurate analysis of bond breaking in BDP nanoparticles could not be realized by using confocal laser scanning microscopy. Hence, the possible products after bond cleavage were quantified by using liquid chromatography tandem mass spectrometry (LC-MS/MS). BDP nanoparticles could be endocytosed into cancer cells, and the disulfide bonds and ester bonds were broken to promote the disassociation of nanoparticles and BDP release. Then, near-infrared BDP nanoparticles were investigated in live mice by near-infrared fluorescence imaging and LC-MS/MS. The release of BDP was low (<10%) and BDP maintained the original dimer structure in vivo, which showed that the bond breaking for BDP nanoparticles was difficult in vivo. These results could help us understand the breaking law of disulfide bonds and ester bonds in nanoparticles and are beneficial for developing practical new drug formulations. [ABSTRACT FROM AUTHOR]