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Noting the “awakening” of data cognition in the governance of global cross-border data flows over the past half-century, this article calls for a deeper understanding and exploration of the cultural dynamics underlying this phenomenon from a constructivist perspective. It identifies “cultural value” as one of the key driving factors in the governance approaches of four representative countries and regions: the US, China, the EU, and Russia. We extract “attribute cognition” and “value pursuit” from the core of data culture to the center of data governance under the concept of “evaluative cognition.” By observing how policy stances change, we separate different evaluative cognitions from a complex game field through a historical and comparative analysis, and thus provide a theoretical understanding of the current intense geopolitical game around data.

With the depletion of conventional light crude oil reserves in China, the demand for heavy oil exploitation has grown, highlighting the increasing significance of enhanced heavy oil recovery. Surfactants reduce oil–water interfacial tension, modify the wettability of reservoir rocks, and facilitate the emulsification of heavy oil. Consequently, investigating the adsorption behavior of surfactants at oil–water interfaces and the underlying mechanisms of wettability alteration is of considerable importance. In this study, the surface tension of four surfactants and their interfacial tension with Gudao heavy oil were measured. Among these, BS-12 exhibited a critical micelle concentration (CMC) of 6.26 × 10−4 mol·dm−3, a surface tension of 30.15 mN·m−1 at the CMC, and an adsorption efficiency of 4.54. In low-salinity systems, BS-12 achieved an ultralow interfacial tension on the order of 10−3 mN·m−1, demonstrating excellent surface activity. Therefore, BS-12 was selected as the preferred emulsifier for Gudao heavy oil recovery. Additionally, FT-IR, SEM, and contact angle measurements were used to elucidate the interfacial adsorption mechanism between BS-12 and aged cores. The results indicate that hydrophobic interactions between the hydrophobic groups of BS-12 and the adsorbed crude oil fractions play a key role. Core flooding experiments, simulating the formation of low-viscosity oil-in-water (O/W) emulsions under reservoir conditions, showed that at low flow rates, crude oil and water interact more effectively within the pores. The extended contact time between heavy oil and the emulsifier led to significant changes in rock wettability, enhanced interfacial activity, improved oil recovery efficiency, and increased oil content in the emulsion. This study analyzes the role of surfactants in interfacial adsorption and the multiphase flow behavior of emulsions, providing a theoretical basis for surfactant-enhanced oil recovery.

Enhanced oil recovery (EOR) by in situ formation of oil-in-water emulsion in heavy oil cold production technology has received growing interest from the petroleum industry. We present an experimental study of emulsification of model oils prepared by heavy oil and its functional group compositions dissolved into toluene brought into contact with a surfactant solution. The effects of functional group composition, emulsifier concentration, temperature, pH and stirring speed on the emulsification rate of heavy oil was investigated. A second-order kinetic model characterizing the temporal variation of conductivity during the emulsification has been established. The results show that acidic and amphoteric fractions exhibit higher interfacial activity, larger emulsification rate constant and faster emulsification rate. With the increase of emulsifier concentration, the emulsification rate constant increase to the maximum value at a concentration of 0.05 mol/L before decreasing. Temperature increase benefits the emulsification rate and the activation energy of the emulsification process is 40.28 kJ/mol. Higher pH and stirring speed indicate faster emulsification rate. The heterogeneity of emulsions limits the accuracy of dynamic characterization of the emulsification process and the determination method of emulsification rate has always been controversial. The conductivity method we proposed can effectively evaluates the emulsification kinetics. This paper provides theoretical guidance for an in-depth understanding of the mechanism and application of cold recovery technology for heavy oil.

Despite the extensive research on developing robust image inpainting algorithms in recent years, there are almost no objective metrics for the quality assessment of inpainted images currently. Inspired by the feature coherence in the inpainted image and the human visual perception mechanism, this paper proposes an image inpainting quality assessment (IIQA) that takes into account both visual saliency and structural features. First, the quality issues associated with image inpainting are categorized into three aspects: incoherent structure, unreasonable texture, and other results that are inconsistent with human visual perception. These quality problems are further expressed as “regions of interest” and extracted by the visual saliency method using the natural statistics model. Subsequently, the structural features are computed based on the nonlinear diffusion of the horizontal and vertical gradient field of the inpainted image. Finally, the IIQA metric incorporates brightness, gradient similarity, structural similarity, and visual saliency is established. The quality evaluation process is conducted by comparing each patch within the inpainted region with its best match from the known region. The quantitative experimental results demonstrate the effectiveness of the proposed method, especially for images with structural discontinuity. A comparative study also shows that the Spearman rank order correlation coefficient of our method achieves 0.875 on certain databases, which outperforms existing IIQA metrics.

Surfactants are hailed as “industrial monosodium glutamate”, and are widely used as emulsifiers, demulsifiers, water treatment agents, etc., in the petroleum industry. However, due to the unidirectivity of conventional surfactants, the difficulty in demulsifying petroleum emulsions generated after emulsification with such surfactants increases sharply. Therefore, it is of great significance and application value to design and develop a novel switchable surfactant for oil exploitation. In this study, a CO2-switchable Gemini surfactant of N,N′-dimethyl-N,N′-didodecyl butylene diamine (DMDBA) was synthesized from 1, 4-dibromobutane, dodecylamine, formic acid, and formaldehyde. Then, the synthesized surfactant was structurally characterized by infrared (IR) spectroscopy, hydrogen nuclear magnetic resonance (1H NMR) spectroscopy, and electrospray ionization mass spectrometry (ESI-MS); the changes in conductivity and Zeta potential of DMDBA before and after CO2/N2 injection were also studied. The results show that DMDBA had a good CO2 response and cycle reversibility. The critical micelle concentration (CMC) of cationic surfactant obtained from DMDBA by injecting CO2 was 1.45 × 10−4 mol/L, the surface tension at CMC was 33.4 mN·m−1, and the contact angle with paraffin was less than 90°, indicating that it had a good surface activity and wettability. In addition, the kinetic law of the process of producing surfactant by injecting CO2 was studied, and it was found that the process was a second-order reaction. The influence of temperature and gas velocity on the reaction dynamics was explored. The calculated values from the equation were in good agreement with the measured values, with a correlation coefficient greater than 0.9950. The activation energy measured during the formation of surfactant was Ea = 91.16 kJ/mol.

Bone is a favorable microenvironment for tumor growth and a frequent destination for metastatic cancer cells. Targeting cancers within the bone marrow remains a crucial oncologic challenge due to issues of drug availability and microenvironment-induced resistance. Herein, we engineered bone-homing polymeric nanoparticles (NPs) for spatiotemporally controlled delivery of therapeutics to bone, which diminish off-target effects and increase local drug concentrations. The NPs consist of poly(d , l -lactic-co-glycolic acid) (PLGA), polyethylene glycol (PEG), and bisphosphonate (or alendronate, a targeting ligand). The engineered NPs were formulated by blending varying ratios of the synthesized polymers: PLGA- b -PEG and alendronate-conjugated polymer PLGA- b -PEG-Ald, which ensured long circulation and targeting capabilities, respectively. The bone-binding ability of Ald-PEG-PLGA NPs was investigated by hydroxyapatite binding assays and ex vivo imaging of adherence to bone fragments. In vivo biodistribution of fluorescently labeled NPs showed higher retention, accumulation, and bone homing of targeted Ald-PEG-PLGA NPs, compared with nontargeted PEG-PLGA NPs. A library of bortezomib-loaded NPs (bone-targeted Ald-Bort-NPs and nontargeted Bort-NPs) were developed and screened for optimal physiochemical properties, drug loading, and release profiles. Ald-Bort-NPs were tested for efficacy in mouse models of multiple myeloma (MM). Results demonstrated significantly enhanced survival and decreased tumor burden in mice pretreated with Ald-Bort-NPs versus Ald-Empty-NPs (no drug) or the free drug. We also observed that bortezomib, as a pretreatment regimen, modified the bone microenvironment and enhanced bone strength and volume. Our findings suggest that NP-based anticancer therapies with bone-targeting specificity comprise a clinically relevant method of drug delivery that can inhibit tumor progression in MM.

In challenging reservoirs where thermal recovery falls short, cold or chemical oil recovery methods are crucial. Spontaneous emulsification (SE), triggered by gentle disturbance, significantly enhances oil recovery. In elucidating SE mechanisms and kinetics, SE processes via direct contact between oil and aqueous phases without stirring were conducted. The effects of temperature, emulsifier concentration, pH, NaCl concentration, and the oil-to-water ratio on SE were investigated through droplet size analysis and turbidity measurements. Furthermore, the emulsification mechanism and derived emulsification kinetics based on turbidity data were obtained. The results underscore the feasibility of SE for oil–water systems, reducing viscous and capillary resistances without agitation. The emulsified oil mass increased with the temperature, pH, and aqueous-to-oil phase volume ratio while decreasing with the NaCl concentration. In this study, for GD-2 crude oil, the optimal emulsified oil amount occurred at a betaine surfactant (BetS-2) emulsifier concentration of 0.45%. Microscopic photo analysis indicated narrow particle size distributions and small droplets, which remained stable over time under various experimental conditions. A combined SE mechanism involving ultralow interfacial tension, interfacial turbulence due to Marangoni effects, and “diffusion and stranding” due to in situ emulsifier hydrophilicity, was speculated. Additionally, an analogous second-order kinetic equation for SE was proposed, indicating exceptional correlation with calculated and experimentally measured values. This study offers theoretical insight for enhancing oil recovery in chemical and cold production of heavy oil in oilfields.

The influence of inflow angle on the stall characteristics of a vertical axial flow pump is investigated numerically by solving the unsteady Reynolds-averaged Navier–Stokes equations. The study predicts both performance parameters and internal flow structures under varying inflow conditions. It is found that as the deflection angle decreases, both the critical and deep stall points shift toward higher flow rates. For the −30° scheme, the design efficiency and design head decrease by 16.27% and increase by 19.59%, respectively, compared to the 0° scheme. As stall develops, an axisymmetric blockage region forms at the impeller inlet, which reduces axial velocity and increases the impeller’s angle of attack. Under design conditions, a smaller deflection angle exacerbates boundary layer separation near the blade leading edge, thereby weakening the local work capacity and intensifying turbulent dissipation. Furthermore, although a reduced deflection angle promotes an earlier onset of stall, it also leads to a decrease in the instability intensity of the stall flow field. These results reveal a critical trade-off: while a smaller deflection angle promotes an earlier stall onset, it effectively mitigates the intensity of stall instability, providing crucial guidance for optimizing the hydraulic design and operational stability of vertical axial flow pumps.

A single load compression test of rock-coal-rock assemblages (RCRs) containing coal bodies with different inclinations was carried out with the research background of mining deep, large-steep coal seams. It was found that the larger the inclination angle of the coal body in the RCR samples, the larger the compaction stage of the samples and the smaller the uniaxial compressive strength value. In addition, both the maximum acoustic emission (AE) energy of the samples and the cumulative AE energy at the moment of destruction decreased with the increase of the inclination angle of the coal body in the form of exponential relativities. Also, the input energy and ultimate elastic energy of the samples at the peak stress moment decreased with increased inclination angle of the coal body. Furthermore, both of them changed with the inclination angle of the coal body in accordance with the exponential relationship; meanwhile, when the applied load exceeded the peak strength, the dissipative energy of the RCR samples increased rapidly due to the loss of load-bearing capacity. At the peak moment, the percentage of dissipated energy of the samples increased exponentially with the increase of the inclination angle of the coal body. This study has certain reference significance for the prevention and control of dynamic disasters during the mining of large angle coal seams.

The exit-hole in friction stir spot welded (FSSWed) 2024-T4 aluminum alloy joints was successfully repaired by using a three-phase secondary rectification resistance spot welding machine, which is termed as filling exit-hole based on resistance welding (FEBRW). The filling dynamic behavior of force was recorded by a device monitoring. Optical microscope (OM), electron backscatter diffraction (EBSD), and tensile shear tests and finite element modelling were conducted to investigate the repairing stages and bonding mechanisms of the repaired joints in detail. Results showed that exit-hole was completely filled and repaired experiencing three stages. Metallurgical bonding was achieved between plug and exit-hole wall in two forms, including melting bonding in the middle of the joints and partial diffusion bonding on both the upper and bottom of the joints. The highest tensile shear strength of the repaired joints was 7.43 kN, which was 36.3% higher than that of the as welded joints. Resistance welding paves an efficient way to repair the exit-hole in FSSWed joints.