Optimization of a high-pressure pore water extraction device.
High-pressure squeezing is a technique used for the extraction of the pore water of porous materials such as sediments, soils, rocks, and concrete. The efficiency of extraction depends on the maximum pressures on the materials. This article presents the design of a high-pressure device reaching an axial pressure of 1000 MPa which has been developed to improve the efficiency of extraction. The increase in squeezing pressure implies high stresses inside the chamber, so specialized expertise was required to design a safe, functional device that could withstand pressures significantly higher than common laboratory equipment. The design includes finite element calculations, selection of appropriate materials, and descriptive construction details for the apparatus. It also includes an experimental study of the performance of the apparatus in terms of extraction efficiency.
Objective To control the quality of Herba Leonuri by studying the content of stachydrine hydrochloride in different parts of it. Method A HPLC method was developed for the content detetmination of stachydrine hydrochloride in flower, stem, leafage from Herba Leonuri. Spherisorb SCX colum was used with mobile phase of 20 mmol/L sodium dihydrogen phosphate (containing 0.04% triethylamine and 0.15% phosphoric acid). The colum temperature was 25 ℃, the detective wavelength was 192 nm. Results Stachydrine hydrochloride content was the highest in leafage and the lowest in stem. Conclusion To ensure the quality of Herba Leonuri, it is significant to choose medical material with more leafage.