Ion-beam-spurted dimethyl-sulfate-doped PEDOT:PSS composite-layer-aligning liquid crystal with low residual direct-current voltage

2016 ◽  
Vol 109 (10) ◽  
pp. 101901 ◽  
Author(s):  
Yang Liu ◽  
Ju Hwan Lee ◽  
Dae-Shik Seo ◽  
Xiang-Dan Li
Keyword(s):  
Liquid Crystal ◽  
Direct Current ◽  
Ion Beam ◽  
Composite Layer ◽  
Dimethyl Sulfate ◽  
Current Voltage ◽  
Direct Current Voltage

scholarly journals A Novel Technique for Determination of Residual Direct-Current Voltage of Liquid Crystal Cells with Vertical and In-Plane Electric Fields

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 816
Author(s):  
Msanobu Mizusaki ◽  
Shoichi Ishihara
Keyword(s):  
Liquid Crystal ◽  
Electric Field ◽  
Electric Fields ◽  
Direct Current ◽  
Fringe Field ◽  
Average Value ◽  
Novel Technique ◽  
Current Voltage ◽  
Direct Current Voltage ◽  
Two Peaks

Generation of residual direct-current (DC) voltage (VrDC) induces serious image sticking of liquid crystal displays (LCDs). In this study, a novel technique to determine the VrDC of LC cells is proposed. We found that the VrDC could be determined from a current-voltage (I-V) curve obtained by the application of triangular voltage. In the case of a vertically aligned twisted nematic (VTN) mode LC cell, where a vertical electric field is applied, the I-V curve shows maximum and minimum current peaks owing to rotation of an LC director, and the VrDC is able to be determined from an average value of the two peaks. On the other hand, in the case of a fringe field switching (FFS) mode LC cell, where an in-plane (lateral) electric field is applied from comb electrodes, the current peaks derived from the rotation of the LC director do not appear. Therefore, we could not adopt the same way with that of the VTN mode LC cell. However, we found that there were two minimum current peaks derived from minimum capacitances of the FFS mode LC cell, and could determine the VrDC by using these two current peaks. The proposed technique would be useful for the evaluation of the VrDC of the LCDs, where the electric field is applied both vertically and laterally.

scholarly journals Energy Flux on a Micromotor Operating under Stationary Direct Current Voltage

2021 ◽  
pp. 127197
Author(s):  
Wenyu Zhang ◽  
Kohei Ohara ◽  
Yasunao Okamoto ◽  
Erika Nawa-Okita ◽  
Daigo Yamamoto ◽  
...  
Keyword(s):  
Energy Flux ◽  
Direct Current ◽  
Current Voltage ◽  
Direct Current Voltage

Experimental Study on Direct Current Voltage Assisted Carbonated Water-Flooding Mechanism in Tight Oil Reservoir

2021 ◽  
Author(s):  
Rukuan Chai ◽  
Yuetian Liu ◽  
Yuting He ◽  
Qianjun Liu ◽  
Wenhuan Gu
Keyword(s):  
Crude Oil ◽  
Direct Current ◽  
Oil Recovery ◽  
Co2 Sequestration ◽  
Water Flooding ◽  
Current Voltage ◽  
Direct Current Voltage ◽  
Carbonated Water ◽  
Ft Icr Ms ◽  
Ft Icr

Abstract Tight oil reservoir plays an increasingly important role in the world energy system, but its recovery is always so low. Hence, a more effective enhanced oil recovery (EOR) technology is urgently needed. Meanwhile, greenhouse effect is more and more serious, a more effective carbon capture and sequestration (CCS) method is also badly needed. Direct current voltage assisted carbonated water-flooding is a new technology that combines direct current voltage with carbonated water-flooding to enhance oil recovery and CO2 sequestration efficiency, simultaneously. Experimental studies were conducted from macroscopic-scale to microscopic-scale to study the performance and mechanism of direct current voltage assisted carbonated water-flooding. Firstly, core flood experiments were implemented to study the effect of direct current voltage assisted carbonated water on oil recovery and CO2 sequestration efficiency. Secondly, contact angle and interfacial tension/dilatational rheology were measured to analyze the effect of direct current voltage assisted carbonated water on crude oil-water-rock interaction. Thirdly, total organic carbon (TOC), gas chromatography (GC), and electrospray ionization-fourier transform ion cyclotron resonance-mass spectrometry (ESI FT ICR-MS) were used to investigate the organic composition change of produced effluents and crude oil in direct current voltage assisted carbonated water treatment. Through direct current voltage assisted carbonated water-flooding experiments, the following results can be obtained. Firstly, direct current voltage assisted carbonated waterflooding showed greater EOR capacity and CO2 sequestration efficiency than individual carbonated water and direct current voltage treatment. With the increase of direct current voltage, oil recovery increases to 38.67% at 1.6V/cm which much higher than 29.07% of carbonated water-flooding and then decreases, meanwhile, CO2 output decreases to only 35.5% at 1.6V/cm which much lower than 45.6% of carbonated water-flooding and then increases. Secondly, in direct current voltage assisted carbonated water-flooding, the wettability alteration is mainly caused by carbonated water and the effect of direct current can be neglected. While both carbonated water and direct current have evident influence on interfacial properties. Herein, with direct current voltage increasing, the interfacial tension firstly decreases and then increases, the interfacial viscoelasticity initially strengthens and then weakens. Thirdly, GC results indicated that crude oil cracking into lighter components occurs during direct current voltage assisted carbonated water-flooding, with the short-chain organic components increasing and the long-chain components decreasing. Meanwhile, TOC and ESI FT ICR-MS results illustrated that CO2 electroreduction do occur in direct current voltage assisted carbonated water-flooding with the dissolved organic molecules increases and the emergence of formic acid. Conclusively, the synergy of CO2 electrochemical reduction into formic acid in aqueous solution and the long-chain molecules electrostimulation pyrolysis into short ones in crude oil mutually resulted in the enhancement of crude oil-carbonated water interaction. This paper proposed a new EOR & CCS technology-direct current voltage assisted carbonated water-flooding. It showed great research and application potential on tight oil development and greenhouse gas control. More work needs to be done to further explore its mechanism. This paper constructs a multiscale & interdisciplinary research system to study the multidisciplinary (EOR&CCS) problem. Specifically, a series connected physical (Core displacement, Contact angle, and Interfacial tension/rheology measurements) and chemistry (TOC, GS, and ESI FT ICR-MS) experiments are combined to explore its regularity and several physics (Atomic physics) and chemistry (Electrochemistry/Inorganic Chemistry) theories are applied to explain its mechanisms.

Sign in / Sign up

Export Citation Format

Share Document