Ultrasonic technology was applied for phenolic compounds extraction from the Pinus koraiensis bark (PKB) and response surface methodology (RSM) was used to optimize the effects of processing parameters on phenolic compounds yields. When ultrasonic power 160W,three independent variables were ultrasonic extraction time (X1 20-40min), ratio of water to raw material (X2 1:20-1:40 g/mL)and ethanol concentration(X3 20%-60%), respectively.The optimal extraction conditions of phenolic compounds were determined as follows: Ultrasonic extraction time 30.61 min, ratio of water to raw material 30.79 mL/g and ethanol concentration 42.2%. Under these conditions, the experimental yield of phenolic compounds was 8.2409 ± 0.0648‰, well matched with the predicted models with the coefficients of determination (R2) of 0.9920, which was agreed closely with the predicted value (8.2963‰).
Coal gangue is a byproduct of mining process, filling the gangue in the road embankment can reduce the pollution caused by the gangue accumulation. Because the formation and type of rock is different, the performance of gangue is different. In this paper, the main types of gangue of Handan & Xingtai coal mining area was taken laboratory test, the mechanical properties and chemical properties of different gangues were compared to determine the feasibility of gangue filling in the road embankment, and the performance law of coal gangue.
Group technology is a system approach that organizes low volume production reasonably. Parts classification and coding systems are introduced mainly in this paper. And parts classification into group methods is recommended in detail. Typical parts coding and classification is described in the paper. Lastly, computer-assisted coding and classification is introduced simply.
In view of current production technology of asphalt concrete mixing plant and technology, a distributed computer control system based on PLC and field bus is developed. The compensation iteration self-learning algorithm is adopted, the compensation amount of learning algorithm of the system is designed and the course program control algorithm is presented. Therefore the precision of the system’s measurement and control is improved and the transmission error is reduced.
designed a equipment for testing the strength of seats and head restraints, the equipment can testing the seats and head restraints with the standard of GB 11550-1995 5.2. The equipment was composed of one upper cylinder elevating system, a beam elevating system, two load cylinders and a hydraulic station. In addition to designed the principle of the hydraulic system.
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