Permeability Modification Using a Reactive Alkaline-Soluble Biopolymer

Polymer injection has been used in reservoirs to alleviate contrasting permeability zones to enhance oil recovery (EOR). Polymer technology relies mainly on the use of polyacrylamides cross-linked by a hazardous metal or organic. Contemporary polymer plugging has investigated the stimulation of in-situ microorganisms to produce polymers (Jenneman et. al., 2000) and the use of biocatalysts to trigger gelling (Bailey et. al., 2000). The use of biological polymers are advantageous in that they can block high permeability areas, are environmentally friendly, and have potential to form reversible gels without the use of hazardous cross-linkers. Recent efforts have produced a reactive alkaline-soluble biopolymer from Agrobacterium species ATCC # 31749 that gels upon decreasing the pH of the polymeric solution. Microbial polymers are of interest due to their potential cost savings, compared to conventional use of synthetic chemical polymers. Numerous microorganisms are known to produce extracellular polysaccharides. One microbiological polymer of interest is curdlan, â - (1, 3) glucan, which has demonstrated gelling properties by a reduction in pH. The focus of this study was to determine the impact an alkaline-soluble biopolymer can have on sandstone permeability

Design Considerations for Artificial Lifting of Enhanced Geothermal System Fluids

This work evaluates the effect of production well pumping requirements on power generation. The amount of work that can be extracted from a geothermal fluid and the rate at which this work is converted to power increase as the reservoir temperature increases. Artificial lifting is an important issue in this process. The results presented are based on a configuration comprising one production well and one injection well, representing an enhanced geothermal system. The effects of the hydraulic conductivity of the geothermal reservoir, the flow rate, and the size of the production casing are considered in the study. Besides submersible pumps, the possibility of using lineshaft pumps is also discussed

Quantum frequency conversion and single-photon detection with lithium niobate nanophotonic chips

In the past few years, the lithium niobate on insulator (LNOI) platform has revolutionized lithium niobate materials, and a series of quantum photonic chips based on LNOI have shown unprecedented performances. Quantum frequency conversion (QFC) photonic chips, which enable quantum state preservation during frequency tuning, are crucial in quantum technology. In this work, we demonstrate a low-noise QFC process on an LNOI nanophotonic platform designed to connect telecom and near-visible bands with sum-frequency generation by long-wavelength pumping. An internal conversion efficiency of 73% and an on-chip noise count rate of 900 counts per second (cps) are achieved. Moreover, the on-chip preservation of quantum statistical properties is verified, showing that the QFC chip is promising for extensive applications of LNOI integrated circuits in quantum information. Based on the QFC chip, we construct an upconversion single-photon detector with the sum-frequency output spectrally filtered and detected by a silicon single-photon avalanche photodiode, demonstrating the feasibility of an upconversion single-photon detector on-chip with a detection efficiency of 8.7% and a noise count rate of 300 cps. The realization of a low-noise QFC device paves the way for practical chip-scale QFC-based quantum systems in heterogeneous configurations.Comment: 8pages, 6 figures, 1 tabl

Metabolomic profiling of Wilson disease, an inherited disorder of copper metabolism, and diseases with similar symptoms but normal copper metabolism

Abstract Background Wilson’s disease (WD) is a hereditary disorder that results in the accumulation of copper. The pathogenic mechanism is not well understood, and diagnosing the disease can be challenging, as it shares similarities with more prevalent conditions. To explore the metabolomic features of WD and differentiate it from other diseases related to copper metabolism, we conducted targeted and untargeted metabolomic profiling using ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and liquid chromatography-tandem mass spectrometry (LC-MS). We compared the metabolomic profiles of two subgroups of WD patients, namely hepatic WD (H-WD) and neurological WD (N-WD), H-WD patients and liver cirrhosis patients (who exhibit similar symptoms but have normal copper levels), and N-WD patients and Parkinson’s disease patients (who exhibit similar symptoms but have normal copper levels). Results Our pairwise comparisons revealed distinct metabolomic profiles for male and female WD patients, H-WD and N-WD patients, N-WD and Parkinson’s disease patients, and H-WD and liver cirrhosis patients. We then employed logistic regression analysis, receiver operating characteristic (ROC) analysis, and model construction to identify candidate diagnostic biomarkers that differentiate H-WD from liver cirrhosis and N-WD from Parkinson’s disease. Based on the spatial distribution of data obtained via PLS-DA analysis, we discovered variations in hydrophilic metabolites (aminoacyl-tRNA biosynthesis; alanine, aspartate, and glutamate metabolism; phenylalanine metabolism; arginine biosynthesis; and nicotinate and nicotinamide) and lipophilic metabolites (TG(triglyceride) (16:0_16:1_22:6), TG (16:0_16:0_22:6), and TG (16:0_16:1_22:5)) between H-WD and N-WD. Moreover, WD patients display metabolic traits that distinguish it from comparable conditions (liver cirrhosis and Parkinson’s disease). Conclusions Our analysis reveals significant variations in the levels of metabolites in critical metabolic pathways and numerous lipids in WD.ROC analysis indicates that three metabolites may be considered as candidate biomarkers for diagnosing WD