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Taking a new type of 35 pumping unit suitable for deep well mining as the research object, the mechanical analysis of its gear long ring rack transmission mechanism is carried out to solve the problems of short operation cycle and high energy consumption in deep well mining with electric submersible pump. The mechanical model of the transmission mechanism is established and the force variation law of the gear long ring rack is obtained in the process of reversing. Based on the dynamic simulation of the pumping unit operation process using Adams, the dynamic characteristics of the transmission mechanism and rollers are studied and the influence of dynamic on the pumping unit operation state is analyzed. The results show that the force of the transmission mechanism changes with the gear position in the process of commutation. During the up and down stroke, the size and direction of the force on the long ring rack are different. The rack box is overturned around its own x, y and z axes. The pneumatic counterweight of 7 t is the best counterweight of the pumping unit. The research results can provide a theoretical reference for the further improvement and optimization of the pumping unit parts.

Gold and silver nanostructures (such as Au nanorods, Ag nanoplates, nanocubes and so on) exhibit strong and tunable surface plasmon resonance in the near-infrared region (NIR). Under a certain NIR laser irradiation, noble metal nanostructrues achieve a high photo-thermal effect, which would be useful in the therapy. Au nanorods with longitudinal surface plasmon resonance (SPRL) shifting in the region of 650-1 100 nm are synthesized by a "seed" method. Ag nanoplates and nanocubes with SPR located in the region of 650-850 nm are produced by a hydrothermal method. Through adjusting laser power and irradiating time, the changes of colloids are studied under NIR laser irradiation, and then the changes are compared with that of water. Under low power laser irradiation (808 nm, <1 W), temperature of Au nanorods colloid increases to about 57 °C. While Au nanorods undergo deformation from rod to spherical particle under irradiation of high power (1 064 nm, 8 W), resulting in the disappearance of SPRL. Under 808 nm NIR laser irradiation, morphology evolutions and photo-thermal conversion of Ag nanostructures are also studied with change of power and irradiation time. Ag nanostructures have a lower photo-thermal conversion compared with that of Au nanorods colloid. Snipping and dendrite can be observed for Ag nanoplates after irradiating, while Ag nanocubes have no obvious shape change. [ABSTRACT FROM AUTHOR]

This study briefly introduces the basic theory of sterilization, the characteristics of ethylene oxide sterilization for medical devices and the key factors about sterilization effectiveness, analyzes and compares three methods used in the product release of medical devices sterilized by ethylene oxide: test for sterility, traditional release and parametric release, and focuses on the theoretical basis, feasibility, validation requirements, advantages and disadvantages of parametric release.

We induced embryogenic calli (EC) and non-embryogenic calli (NEC) from flower filaments of Vitis vinifera L. cv. Chardonnay about 10 days before full bloom. The callus were sub-cultured, observed and verified by somatic embryo induction. PCR primers for VvSUC12 and VvSCU27 were designed according to the corresponding sequences in GenBank. After RNA extraction with RNAplant for EC and NEC cell lines, we synthesized the 1st strand DNA for semi quantitative RT-PCR, and normalized the density of the bands against house-keeping gene Actin. The results of 31 cycles semi-quantitative RT-PCR showed that VvSUC12 was highly expressed in both EC and NEC, with higher expression intensity in NEC than in EC, but not reached the significant level; while the expression of VvSUC27 was only detected in EC, and the expression level was significantly lower than that of VvSUC12. We increased the semi-quantitative RT-PCR cycle number to 35 and found that VvSUC27 gene was weakly expressed in NEC, in EC the intensity of the band was increased comparing with 31 cycles, and the expression level was higher than that of NEC. The paper discussed the differential expression of the two sucrose transporters and their relationship with the sucrose in the tissue culture medium.

Anion-exchange resin, D201 was used to prepare ferulic acid from the enzymatic hydrolysate of wheat-bran and the influence of adsorption and desorption operation was researched. The optimal technology is as follows: under the room-temperature, the concentration of ferulic acid in the extraction solution is 2000 mg/L to approximately 3000 mg/L, pH and flow velocity were kept around 9.0 and 1 ml/min respectively; elution solution is composed of ethanol: water: HCl in ratio 60:36:4 (v/v), and the velocity of elution is 1 ml/min. Under optimal conditions,the recovery percent of ferulic acid from enzymatic hydrolysate exceed 97% and the purification production is in evidence.