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Reed Pulp was Raw Material that Pretreated by Four Methods {ultrasonic, Microwave, N, N-Dimethyl Acetamide (DMAc) and Tetrahydrofuran (THF)}. Reed Microcrystalline Cellulose (MCC) was Prepared by the Dilute Hydrochloric Acid Hydrolysis from Pretreated Reed Pulp. the Influences of Pretreatment Methods on Crystalline Type, Crystallinity and Crystallite Size of MCC were Investigated by X-Ray Diffraction (XRD). the Results Showed that the Crystallinity of MCC with Four Pretreatment Methods was 68.45%, 62.28%, 63.21% and 69.56%, Respectively. the Average Crystallite Size of MCC Prepared by Hydrolysis after Pretreated by Dmac was the Largest. whereas, the Crystal Type of MCC was Not Changed, it was still the Cellulose Type I. Comprehensive Analysis Indicated that the Effects of MCC Prepared by Hydrolysis after Pretreated by Ultrasonic were the Best.

PO/CB (Polyolefin/Carbon Black) PTC (Positive Temperature Coefficient) composite with easy processing, low cost characteristics has been applied widely. But it suffered from a relatively short lifespan because of its NTC (Negative Temperature Coefficient) effect and low PTC intensity. In order to overcome this shortcoming, the CF was calcination-treated to prepare LDPE/CF (Low Density Polyethylene/Carbon Fiber) PTC composite. Influence of length, content and treatment method of CF on PTC properties of composites was investigated. Results showed that 0.5mm length CF in composites had higher PTC intensity than that of 2mm length CF. PTC intensity of the composites was enhanced more effectively by calcination treated CF compared to the untreated CF. The maximum PTC intensity was 8.1 when CF’s content was at 8wt%.

To evaluate the optimum administration routes of saikosaponin in the treatment of epilepsy by comparing the plasma pharmacokinetics and the brain pharmacokinetics after different administration routes of saikosaponin. After receiving saikosaponin in different administration routes, the mice were sacrificed to collect the blood and brain tissues. The acetonitrile and methanol (9∶1) were used to precipitate the plasma protein. The concentration of the SSa in mice plasma and brain was determined by UPLC-MS/MS, and the pharmacokinetic parameters, bioavailability, the brain targeting coefficient (Re) and the brain drug targeting index (DTI) were calculated with Kinetica software. The relative brain Re was 142.17% by intranasal administration, with DTI of 3.06, significantly higher than those by the injections; in addition, the brain DTI was 1.25 by gavage administration. The brain drug targeting of saikosaponin by intranasal administration was higher than that by injection and gavage administration, indicating the advantages of the intranasal administration on medicine absorption into the brain.

In this study, the changes of bullatine A in plasma and skin of mice with time in microemulsion gel and ordinary gel of Aconitum brachypodum total alkaloids were compared through UPLC-MS/MS, and their pharmacokinetic parameters were also compared and analyzed, to investigate the feasibility of microemulsion agent in the transdermal drug delivery. UPLC-MS/MS method for simultaneous determination of bullatine A in plasma and skin had high sensitivity and was in line with the pharmacokinetic study requirements for transdermal drug delivery. The main pharmacokinetic parameters for microemulsion gel in the plasma were as follows: Cmax=(37.62±14.31) μg•L⁻¹, Tmax=(3.40±1.34) h, AUC0-∞=(1 027.7±260) μg•L⁻¹•h⁻¹, MRT=(34.80±12.31) h, MRTlast=(10.68±0.57) h, t1/2=(23.11±9.20) h; main pharmacokinetic parameters for ordinary gel in the blood: Cmax=(52.23±15.90) μg•L⁻¹, Tmax=(4.00±0.00) h, AUC0-∞=(728.60±280.80) μg•L⁻¹•h⁻¹, MRT=(20.69±3.98) h, MRTlast=(9.34±0.42) h, t1/2=(14.69±3.15) h. The results showed that the microemulsion gel had more stable transdermal absorption, longer duration of action and higher bioavailability than ordinary gel, indicating that the microemulsion gel had a good and stable transdermal effect. There was no significant difference in bioavailability of bullatine A in skin between microemulsion gel and ordinary gel.

To establish UPLC-MS/MS method for determination of the recovery rate of bullatine A microdialysis probe. The concentration difference method(incremental method, decrement method) was used to measure in vitro recoveries, and the effects of perfusate pH value, flow rate, concentration, and temperature on the recovery rate were investigated to explore the feasibility of microdialysis for the pharmacokinetic study of bullatine A. The method of UPLC-MS/MS showed good linear relationship within the required range; the specificity, recovery rate and precision of chromatography met the requirements of microdialysis samples. There was no significant difference in the measured recovery rate between incremental method and decrement method. Under the same conditions, in vitro recovery rate of the probe was decreased with the increase of flow rate, and was significantly increased with the increase of temperature, but was independent of bullatine A concentrations around the probe. The results showed that, microdialysis technology can be used for the pharmacokinetic study of bullatine A, and retrodialysis method (decrement method) can be used for the determination of the in vivo recovery rate of bullatine A microdialysis.

According to the requirements of the ground demonstration test for small-sized docking mechanism, a set of ground test platform was designed, which can simulate the weightless environment of space and provide six degrees of freedom for the docking mechanism. This paper elaborated the structure and working process of the test platform, and used the way of rigid-flexible coupling to analysis the test platform in dynamics simulation by ADAMS. The mechanical properties of the platform’s key parts during the collision process were obtained