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Type synthesis of the fully-decoupled two-rotational and one-translational parallel mechanism
Yanbin Zhang,Xuemin Wei,Shuang Zhang,Zhenzhen Chang,Yaoguang Li 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.12
Type synthesis of parallel mechanism is regarded as the theoretical basis and source for the original innovation design of mechanical devices and robots. A new method for type synthesis of the fully-decoupled two-rotational and one-translational (2R1T) parallel mechanisms with three degrees of freedom is proposed in this paper. Based on the actuation wrench screw theory, the mathematical model mapping the input and output velocity vector space of the fully-decoupled 2R1T parallel mechanism is established. The actuation wrench screws and the actuated twist screws of the corresponding branches are derived according to the mathematic model. The forms of the unactuated screws are determined in terms of the reciprocal product theory. Structural synthesis of the branch chains is realized. Then type synthesis of parallel mechanisms is completed as well and lots of novel mechanisms are obtained. Finally, a 2RUPU-PU parallel mechanism synthesized is taken as an example to analyze its mobility and kinematics. Results show that the mechanism has two-rotational and onetranslational degrees of freedom and its Jacobian matrix is a diagonal matrix, i.e., it has the fully-decoupled kinematic characteristics. Therefore, the method proposed is correct and effective to synthesize the fully-decoupled 2R1T parallel mechanisms.
Ziqiang Zhang,Yumei Liu,Xuemin Zhu,Lan Wei,Jiamin Zhu,Ke Shi,Guotao Wang,Li Pan 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.4
Previous studies have shown that the sciatic nerve has neurotrophic activity, and nerve regeneration, differentiation, and axon outgrowth can be modulated by different sciatic nerve preparations. However, numerous animals may have to be sacrificed to obtain enough sciatic nerves to make a sciatic nerve preparation. Some studies have demonstrated that the role of sciatic nerve preparations in neural differentiation depends on the neurotrophins that Schwann cells secrete, and these factors are highly conserved among different species. To reduce the use of experimental animals, in this study, we made a leachate by using the sciatic nerve of cattle and explored its effect on neuronal differentiation of rat PC12 cells (a useful model for studying neuronal differentiation). Results showed the neurite outgrowth of PC12 cells treated with the cattle sciatic nerve leachate for 3, 6, and 9 days was significantly improved, and the expressions of β3-tubulin and microtubule-associated protein 2 (two neuron-specific proteins) were increased. Moreover, the ERK1/2 signaling pathway was activated after PC12 cells were incubated with cattle sciatic nerve leachate for 9 days. Thus, a sciatic nerve leachate obtained from cattle can effectively induce neuronal differentiation of rat PC12 cells via ERK1/2 signaling pathway.
Fang, Luwei,Tian, Minglei,Yan, Xuemin,Xiao, Wei,Row, Kyung Ho Elsevier 2019 Journal of chromatography Vol.1592 No.-
<P><B>Abstract</B></P> <P>A convenient, and efficient multi-phase extraction method was used to isolate aristolochic acid from real samples. To increase the efficiency, a new dual ionic liquid-immobilized silica was used as a sorbent and the effects of the adsorption conditions were investigated. IM-BIM@Sil in a methanol/water (60:40, v/v) solution at 60 °C extracted the highest amount of aristolochic acid (16.69 mg/g) compared to the other sorbents examined. The sorbent was then applied to the multi-phase extraction of aristolochic acid. After extraction eight times, 2.4–70.9 × 10<SUP>−3</SUP> mg/g of aristolochic acid was isolated from nine real samples after several washing and elution steps. The recoveries of aristolochic acid ranged from 70.0% to 110.6% with relative standard deviations of 3.5%–9.1%, highlighting the accuracy of this method.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dual ionic liquid-immobilized silicas were created. </LI> <LI> High efficiency multi-phase extraction was applied in isolation. </LI> <LI> High adsorption amount of aristolochic acid on new sorbent. </LI> </UL> </P>