Eighteen new diterpenoids, named eurifoloids A-R (1-18), including ingenane (1 and 2), abietane (3-7), isopimarane (8-12), and ent-atisane (13-18) types, along with four known analogues were isolated from Euphorbia neriifolia. Eurifoloid M (13) represents a rare class of ent-atisane-type norditerpenoid. Eurifoloids E (5) and F (6) exhibited significant anti-HIV activities, with EC50 values of 3.58 ± 0.31 (SI = 8.6) and 7.40 ± 0.94 μM (SI = 10.3), respectively.

A model reference adaptive modeling method of ball screw feed system is proposed. Using a low-level system with excellent dynamic characteristics as the reference model and ball screw feed system as the controlled object, this paper establishes model reference adaptive system by Narendra program, achieving exact match between the adjustable system and the reference model through experiment and deriving the low-level model of the ball screw feed system. Then taking the X axis of X-Y work table as an example, a second-order model of the ball screw feed system is established by this method. When 40000 pulse signals are input into the model and the ball screw feed system in 160s respectively, the output error between the two is within ± 0.005mm, thus testifying the higher accuracy of the model obtained.

The dynamic model of micro piezoelectric vibration energy harvesters is established using the theory of strain gradient, the model reflects the effect of the scale of the micro system.The expression of the output voltage is gotten through solving the model, and then the parameters are simulated, the results of simulation accord with the experimental data

Abstract: Determination of multi-elements were studied in the food cooked with medicinal herbs Ophiopogon japonicus（OJ） and Lotus seeds by ICP-AES after HNO3-H2O2 digestion with microwave. The average recoveries are in 91.7%~ 102.4% of As, Cr, Se, Cd, Cu, Mn, Zn, Al, Ba, Fe, Ni, respectively. The relative standard deviation(RSD)is less than 2.8% except Al （9.4%）and detection limit is in the range of 0. 10µg/L ~8.5µg/L except Al （79.6µg/L）. The difference was very obvious（p0.001,except As） that the elements’ content on the comparison OJ with Lotus seeds. There was rich of the trace elements Cu, Zn. The harmful element Al was on the high value（214.7µg/g）in the OJ. It is of important significance to assess the value of the food cooked with medicinal herbs by determination of multiply elements in Lotus seeds, and OJ with ICP-AES. Keyword: multi-elements, the trace elements, the harmful elements, Ophiopogon japonicus, Lotus seeds, ICP-AES