Pre-pumping of coal seam gas by extraction borehole is an effective measure to manage gas. The existing study concluded that the pressure relief zone roadway difficult seal, and thus sealing depth should generally exceed roadway. Based on relationship between roughness GSI, a numerical simulation was carried out with engineering background 22200 machine tunnel E8 Sixth Mine Pingdingshan Tianan ...

In this paper, the efficiency of lipid extraction from macrophytes (Chaetomorpha linum, Ulva laetevirens, Valonia aegagrophyla, Gracilariopsis longissima, Ruppia cirrhosa) for the biodiesel production is evaluated using four different methods based on the Accelerated Solvent Extraction technique. Both wet and dried tissues are extracted and effects induced on lipid recovery by the pressure and ...

introduction thunderstorms pose a significant threat to modern societies and their assets. despite their local-scale characteristics, severe thunderstorms and associated extreme events like heavy rainfall, hail, gusts, or tornadoes can cause considerable damage to agriculture, buildings, or infrastructure, and facilities. thunderstorms are highly localized and largely stationary weather systems...

A rational approach to the development and optimization of solid-phase extraction (SPE) methods is described. The semiautomated scheme allows for the simultaneous testing of multiple chemistries using a custom multiple-sorbent 96-well method development plate. Optimized extraction conditions for up to five analytes are determined in a single 2.5-h experiment. The experiment can be tailored to d...

The main objective of the present study was to investigate the effect of solvent type and ratio as well as the extraction techniques (i.e. supercritical fluid extraction (SFE) and conventional solvent extraction) on betacyanins and antioxidant activity of the peel and fresh extract from the red pitaya (Hylocereus polyrhizus). The peel and flesh extracts obtained by SFE at 25MPa pressure and 10%...

in this work, the solubility of nicotine extracted from tobacco leaves, found in the north of iran, in supercritical carbon dioxide has been measured. also the effects of pressure, temperature, extraction dynamic time, and the organic co-solvent on the amount of nicotine extracted from tobacco leaves have been investigated. it should be stressed that in order to reduce significantly the number ...