The current simple nanofluid flooding method for tertiary or enhanced oil recovery is inefficient, especially when used with low nanoparticle concentration. We have designed and produced a nanofluid of graphene-based amphiphilic nanosheets that is very effective at low concentration. Our nanosheets spontaneously approached the oil-water interface and reduced the interfacial tension in a saline environment (4 wt % NaCl and 1 wt % CaCl 2 ), regardless of the solid surface wettability. A climbing film appeared and grew at moderate hydrodynamic condition to encapsulate the oil phase. With strong hydrodynamic power input, a solid-like interfacial film formed and was able to return to its original form even after being seriously disturbed. The film rapidly separated oil and water phases for slug-like oil displacement. The unique behavior of our nanosheet nanofluid tripled the best performance of conventional nanofluid flooding methods under similar conditions. nanofluid flooding | amphiphilic Janus nanosheets | enhanced oil recovery | climbing film | interfacial film F inding economically viable and environmentally friendly methods to extract the huge amount of residual oil after primary and secondary recovery remains challenging for the oil and gas industry and is also of significant importance in efforts to satisfy the world's increasing energy demand. Nanofluid flooding as an alternative tertiary oil recovery method has been recently reported (1-5). Obviously, simple nanofluid flooding (containing only nanoparticles) at low concentration (0.01 wt % or less) shows the greatest potential from the environmental and economic perspective. Several corresponding oil displacement mechanisms have also been introduced, including reduction of oil-water interfacial tension (6, 7), alteration of rock surface wettability (8-10), and generation of structural disjoining pressure (11-13). However, the oil recovery factor is below 5% with 0.01% nanoparticle loading in core flooding tests in a saline environment (2 wt % or higher NaCl content). Here we show that an oil recovery factor of 15.2% is achieved by using a simple nanofluid of graphene-based Janus amphiphilic nanosheets. To our knowledge, this is the first report of applying nanofluid of amphiphilic Janus two-dimensional materials in tertiary or enhanced oil recovery. We found that in a saline environment, the nanosheets spontaneously approach the oil-water interface, reducing the interfacial tension. A climbing film emerges and encapsulates the oil phase and may carry it forward. Furthermore, we found that a solid-like film forms with strong hydrodynamic power. The film rapidly separates oil and water for slug-like oil displacement. Even though there are ways to achieve 20% enhanced recovery by complicated alkali/surfactant/polymer flooding (14) or by surfactants with added nanoparticles (5), the necessary concentrations of the chemicals and nanoparticles are much higher than 0.01 wt %. Our results provide a nanofluid flooding method for tertiary oil recovery that is compar...

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Background and Aims Hepatocellular carcinoma (HCC) is linked to immunosuppression. Relieving immunosuppression has been an attractive strategy to improve the efficacy of cancer immunotherapy. Peptidoglycan recognition protein 2 (PGLYRP2) is a pattern recognition receptor which is specifically expressed in liver and implicated in the regulation of innate immunity and immunosurveillance. However, the role of hepatic PGLYRP2 in modulating immune responses against HCC remains to be investigated. Approach and Results In this study, we investigated whether PGLYRP2 is able to influence HCC progression through regulating host antitumor immune responses. We demonstrated that PGLYRP2 was down‐regulated in HCC, which was linked with poor prognosis in patients (P < 0.001). PGLYRP2 overexpression in HCC cells significantly enhanced antitumor immune responses in immune‐competent mice and elevated immune response rates of peripheral blood mononuclear cells against HCC. Mechanistically, DNA methyltransferase 3A–mediated promoter hypermethylation was responsible for the down‐regulation of PGLYRP2 in HCC. PGLYRP2 promoted production of chemokine (C‐C motif) ligand 5 (CCL5) in HCC through binding to the CCL5 promoter, which contributed to the enhanced antitumor immunity. Conclusions We provide evidence that tumor‐derived PGLYRP2 acts as a candidate biomarker for adequate immune response against HCC and improved patient outcomes, indicating the importance of hepatic PGLYRP2 in cancer immunosurveillance and in designing immunotherapeutic approaches.

We present a comprehensive overview of the influence of water on coalbed methane production. The influence of water on coalbed methane production is associated with adsorption of water in pores, capillary condensation, micropore filling, adsorption hysteresis and its effect on methane diffusivity, coal swelling due to adsorption of water and a corresponding change in methane permeability, pore saturation by water (water imbibition into pores), and gas-water two-phase flow in the cleats. We consider methods for reducing the negative impact of water on coalbed methane production: carbon dioxide injection and microwave technology. We identify promising areas of study.

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