Cafferic acid-O-methyltransferases (COMT) down-regulated transgenic and wild-type switchgrass were separated into lignocresols (LCs) and sugars by a phase separation method involving 72% sulfuric acid and cresol. The isolated LCs were characterized by FTIR, GPC, 1 H NMR and 2D-HSQC to understand potential structural modification caused by transgenic engineering lignin or phase separation treatment. No significant changes were found in terms of molecular weights and the amount of incorporated p-cresols between transgenic and wild-type switchgrass LCs. However, the compositions, ratios of syringyl (S) units to guaiacyl (G) units, were changed significantly leading to decrease in S units and increase in G units for transgenic switchgrass LC. The benzodioxane structures and 5-hydroxyguaiacyl units were observed in the 2D-HSQC implied that 5-hydroxyconiferyl alcohol was incorporated into lignin as a result of COMT-down-regulation in the transgenic process.

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Pore pressure prediction before drilling is significant on ensuring drilling safety, reasonable drilling mud density, and designing well profile. It can also reduce the drilling cost and protect the hydrocarbon reservoir. With the increasing quality of seismic data and widely application of new methods, high-resolution seismic was used to reduce the uncertainty of the pore pressure prediction in this paper. Through the past years study, workflows were developed which use the high resolution seismic for pore pressure prediction. The workflows mainly include three steps. The first step is the mechanisms analysis for pore pressure prediction. The geological genesis is the key to pore pressure prediction. Base on the geological genesis, Fillippone method was optimization and adjustment, such as seismic velocity analysis and variation rate of seismic velocity estimation based on geological consistency. After the method optimization, the overburden pressure and pore pressure will be estimated by the seismic data, integrated with regional geological data and shallow well logging data. A postmortem from southwest of Iraq is presented showing a successful well that were better predicted before the well were drilled. The prediction result accuracy error is less than 5% compared with the measured data which is tested by well drilling and this indicates that the method can greatly improve the accuracy of pressure prediction before drilling. With the increasing quality of seismic data, the high-resolution seismic data will play more and more important role in pore pressure prediction. The method integrated seismic, geological and well logging data for formation pressure prediction will reduce the uncertainty greatly.