In this paper, we obtained three dimensional digital cores using X-ray CT to describe the rock microstructure and applied the open morphology algorithm to simulate oil and formation water distribution in the pore spac...In this paper, we obtained three dimensional digital cores using X-ray CT to describe the rock microstructure and applied the open morphology algorithm to simulate oil and formation water distribution in the pore space at different water saturations during the oil-displacing water flood process. The resistivity, formation factor, and resistivity index of rocks were calculated using the finite element method （FEM） and we studied the effect of rock wettability on electrical properties. The numerical simulation results indicate that the simulated formation factor and resistivity index of the water wet rock agrees well with experiments over the whole range of water saturation and extends the traditional resistivity experiment. The rock wettablilty has a large influence on the rock resistivity index. The resistivity and saturation exponent of oil wet rock are obviously larger than three of water wet rock.展开更多
The effects of relative humidity (RH) on a printed circuit board finished with electroless nickel immersion gold (PCB-ENIG) under an adsorbed thin electrolyte layer (ATEL) were investigated in situ via the measurement...The effects of relative humidity (RH) on a printed circuit board finished with electroless nickel immersion gold (PCB-ENIG) under an adsorbed thin electrolyte layer (ATEL) were investigated in situ via the measurement of cathodic polarization curves, electrochemical impedance spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to clearly elaborate the corrosion behavior of PCB-ENIG in the atmospheric environment. Results indicated that the cathodic process of PCB-ENIG under ATEL was dominated by the reduction of dissolved oxygen, corrosion products, and H2O. The cathodic current density of PCB-ENIG increased progressively with increasing RH. Moreover, its cathodic current density in the solution was greater than that under ATEL. This result demonstrated that the diffusion process was not the controlling step during the limiting reduction of cathodic oxygen. When the polarization potentials were located in a more negative region, the cathodic polarization current density gradually decreased under 75% and 85% RH. Notably, the anodic process became the controlling step in the extremely thin liquid film during the remainder of the experiment.展开更多
基金sponsored by NSFC(Grant No.40574030)CNPC research project(Grant No.06A30102)
文摘In this paper, we obtained three dimensional digital cores using X-ray CT to describe the rock microstructure and applied the open morphology algorithm to simulate oil and formation water distribution in the pore space at different water saturations during the oil-displacing water flood process. The resistivity, formation factor, and resistivity index of rocks were calculated using the finite element method （FEM） and we studied the effect of rock wettability on electrical properties. The numerical simulation results indicate that the simulated formation factor and resistivity index of the water wet rock agrees well with experiments over the whole range of water saturation and extends the traditional resistivity experiment. The rock wettablilty has a large influence on the rock resistivity index. The resistivity and saturation exponent of oil wet rock are obviously larger than three of water wet rock.
基金Project(51271032)supported by the National Natural Science Foundation of ChinaProject(2014CB643300)supported by the National Basic Research Program of ChinaProject supported by the National Environmental Corrosion Platform,China
文摘The effects of relative humidity (RH) on a printed circuit board finished with electroless nickel immersion gold (PCB-ENIG) under an adsorbed thin electrolyte layer (ATEL) were investigated in situ via the measurement of cathodic polarization curves, electrochemical impedance spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to clearly elaborate the corrosion behavior of PCB-ENIG in the atmospheric environment. Results indicated that the cathodic process of PCB-ENIG under ATEL was dominated by the reduction of dissolved oxygen, corrosion products, and H2O. The cathodic current density of PCB-ENIG increased progressively with increasing RH. Moreover, its cathodic current density in the solution was greater than that under ATEL. This result demonstrated that the diffusion process was not the controlling step during the limiting reduction of cathodic oxygen. When the polarization potentials were located in a more negative region, the cathodic polarization current density gradually decreased under 75% and 85% RH. Notably, the anodic process became the controlling step in the extremely thin liquid film during the remainder of the experiment.
