9 research outputs found
Experimental Study of the Injection System for CO2 Geologic Storage Demonstration
AbstractThe worldwide issue of greenhouse gas reduction has recently drawn great attention to carbon capture and storage (CCS). Almost CCS studies have been focused in the capture technology of carbon dioxide and the geological investigation for underground storage. The study of mechanical injection system for carbon dioxide has not implemented nearly. We are intended to develop a ground system for underground injection of carbon dioxide. In this study, we made lab-scale underground injection system and implemented injection simulation test experimentally. The 10,000 ton/year pilot plant for geological storage of carbon dioxide will be designed on the base of these test results. Major components of the lab-scale underground injection system include a pressure pump and an in-line heater to bring liquid carbon dioxide into its supercritical state. Test results assure that this system readily achieves the designed injection pressure and temperature, showing satisfactory control performance
Perspectives for biocatalytic lignin utilization: cleaving 4-O-5 and C??-C?? bonds in dimeric lignin model compounds catalyzed by a promiscuous activity of tyrosinase
Background: In the biorefinery utilizing lignocellulosic biomasses, lignin decomposition to value-added phenolic derivatives is a key issue, and recently biocatalytic delignification is emerging owing to its superior selectivity, low energy consumption, and unparalleled sustainability. However, besides heme-containing peroxidases and laccases, information about lignolytic biocatalysts is still limited till date.
Results: Herein, we report a promiscuous activity of tyrosinase which is closely associated with delignification requiring high redox potentials (>1.4 V vs. normal hydrogen electrode [NHE]). The promiscuous activity of tyrosinase not only oxidizes veratryl alcohol, a commonly used nonphenolic substrate for assaying ligninolytic activity, to veratraldehyde but also cleaves the 4-O-5 and C??-C?? bonds in 4-phenoxyphenol and guaiacyl glycerol-??-guaiacyl ether (GGE) that are dimeric lignin model compounds. Cyclic voltammograms additionally verified that the promiscuous activity oxidizes lignin-related high redox potential substrates.
Conclusion
These results might be applicable for extending the versatility of tyrosinase toward biocatalytic delignification as well as suggesting a new perspective for sustainable lignin utilization. Furthermore, the results provide insight for exploring the previously unknown promiscuous activities of biocatalysts much more diverse than ever thought before, thereby innovatively expanding the applicable area of biocatalysis
Geochemistry of Geothermal Water in Pohang, Korea
ABSTRACT Hydrogeochemical and isotopic characteristics were investigated for groundwater of the Tertiary basin in southeastern part of Korea where deep drilling is in progress for geothermal investigation. According to geology, the aquifer was distinguished as alluvial, tertiary sedimentary bedrock (bedrock groundwater), and fractured volcanic rock (deep groundwater). Groundwater of each aquifer is distinctively separated in Eh-pH conditions and concentrations of Cl, F, B and HCO 3 . Deep groundwater has very low levels of 3 H and 14 C whereas alluvial groundwater has those of recent precipitation level. However one of deep groundwater show mixed characteristics in terms of hydrochemistry which indicates effect of pumping. Deep groundwaters have temperature of 38 to 43 o C whereas bedrock and alluvial groundwater have temperature less than 20 o C. Fractured basement rock aquifer has a different hydrogeological setting from the bedrock and alluvial aquifer considering hydrogeochemical and isotopic characteristics, and temperature
Three-Dimensional Numerical Simulation Of Saltwater Extraction Schemes To Mitigate Seawater Intrusion Due To Groundwater Pumping In A Coastal Aquifer System
A series of three-dimensional numerical simulations using a multidimensional hydrodynamic dispersion numerical model was performed to analyze various saltwater extraction schemes for mitigating seawater intrusion attributed to groundwater pumping in a coastal aquifer system. A steady-state numerical simulation was performed first to obtain initial (i.e., pregroundwater pumping) steady-state conditions before groundwater pumping, and then a transient-state numerical simulation was performed to obtain intermediate (i.e., postgroundwater pumping) steady-state conditions during groundwater pumping. In the subsequent series of transient-state numerical simulations as scenario and sensitivity analyses, four different saltwater extraction factors such as the amount of saltwater extraction, the number of extraction wells, the horizontal location of extraction wells, and the vertical interval of saltwater extraction were considered to determine an optimal saltwater extraction scheme for the coastal aquifer system threatened with seawater intrusion. The numerical simulation results show that seawater intrusion may be better mitigated when saltwater is extracted at 30% (up to 50%) of the groundwater pumping rate from a single extraction well, which is located horizontally midway between the pumping well and the coastline and is screened through the whole sand aquifer. © 2012 American Society of Civil Engineers
Cissus subtetragona Planch. Ameliorates Inflammatory Responses in LPS-induced Macrophages, HCl/EtOH-induced Gastritis, and LPS-induced Lung Injury via Attenuation of Src and TAK1
Several Cissus species have been used and reported to possess medicinal benefits. However, the anti-inflammatory mechanisms of Cissus subtetragona have not been described. In this study, we examined the potential anti-inflammatory effects of C. subtetragona ethanol extract (Cs-EE) in vitro and in vivo, and investigated its molecular mechanism as well as its flavonoid content. Lipopolysaccharide (LPS)-induced macrophage-like RAW264.7 cells and primary macrophages as well as LPS-induced acute lung injury (ALI) and HCl/EtOH-induced acute gastritis mouse models were utilized. Luciferase assays, immunoblotting analyses, overexpression strategies, and cellular thermal shift assay (CETSA) were performed to identify the molecular mechanisms and targets of Cs-EE. Cs-EE concentration-dependently reduced the secretion of NO and PGE2, inhibited the expression of inflammation-related cytokines in LPS-induced RAW264.7 cells, and decreased NF-κB- and AP-1-luciferase activity. Subsequently, we determined that Cs-EE decreased the phosphorylation events of NF-κB and AP-1 pathways. Cs-EE treatment also significantly ameliorated the inflammatory symptoms of HCl/EtOH-induced acute gastritis and LPS-induced ALI mouse models. Overexpression of HA-Src and HA-TAK1 along with CETSA experiments validated that inhibited inflammatory responses are the outcome of attenuation of Src and TAK1 activation. Taken together, these findings suggest that Cs-EE could be utilized as an anti-inflammatory remedy especially targeting against gastritis and acute lung injury by attenuating the activities of Src and TAK1