Probabilistic response of a fractional-order hybrid vibration energy harvester driven by random excitation.

The stochastic response of a fractional-order hybrid vibration energy harvester is investigated in this paper. Equivalent system can be derived by the variable transformation. Then, the probability density functions of mechanical states are obtained by the stochastic averaging technique. The good agreement between numerical simulation and analytical results demonstrates the effectiveness of the proposed method. Mean square voltage, mean square current, and mean output power are presented to illustrate the device output performance. Results imply that the hybrid vibration energy harvesting system can generate higher mean output power than that from a separate piezoelectric system and an electromagnetic system.

Pharmacokinetics of ambroxol and clenbuterol tablets in healthy Chinese volunteers.

OBJECTIVE: To investigate the pharmacokinetics of Ambroxol and Clenbuterol Tablets in Chinese healthy volunteers after a single or multiple dosages oral administration. METHODS: A total of 9 healthy adult subjects were given Ambroxol and Clenbuterol Tablets in a single dosage or multiple dosages respectively. LC/MS/MS were used for the determination of Ambroxol and Clenbuterol of in plasma. The important pharmacokinetic parameters were calculated by DAS 2.0 software (compartment model). RESULTS: Single and multiple dosage groups of Ambroxol and Clenbuterol were all fitted two-compartment model. The pharmacokinetics fitted first order kinetics process. No difference in pharmacokinetics of Ambroxol in single and multiple dosage groups volunteers was observed, Which showed no marked changes, suggesting that multiple dosing did not influence the velocity of drug metabolism. Moreover, parameters of Clenbuterol had significant difference between the single and multiple dosage groups (P<0.05), showing there was accumulation in the body. 9 subjects had completed single or multiple dosages oral administration test, with no adverse drug reactions appeared during the test. CONCLUSION: There was no obvious accumulation of Ambroxol after repeated dosing. But obvious accumulation of Clenbuterol was noted in multiple-dose administration. The established method is sensitive, accurate, reliable and specific, and it can meet the requirement of clinical pharmacokinetic trial.