In the development process of Block G in Dagang Oilfield, the air foam flooding system exhibits favorable oil displacement performance. However, affected by factors such as foam preparation technology, gas injection volume, gas injection rate and reservoir permeability heterogeneity, gas channeling is prone to occur during oil and gas production. To explore the mechanism of gas channeling in oil reservoirs and its impacts on oil and gas field development, experiments on the oil displacement performance of air foam flooding were conducted using a Brookfield viscometer, gas chromatograph and core flooding apparatus. The experiments investigated the effects of profile control agent types, gas injection modes and reservoir heterogeneity. Corresponding effective technologies for gas channeling control were also proposed. The results show that in the air foam flooding test with heterogeneous models, foam preferentially enters high-permeability layers, which increases seepage resistance and reduces water absorption index, thus achieving excellent effects of water control and oil production enhancement. Compared with conventional air foam flooding, the injection of Cr³⁺ polymer gel and hydrophobic associating polymer can effectively restrain gas channeling, and further improve the oil-increasing and water-reducing performance of air foam flooding. When the injection volume of gel plugging agent is 0.20 PV, the maximum increment of oil recovery factor reaches 15.23%; when the injection volume of polymer is 0.30 PV, the maximum increment of oil recovery factor is 11.35%.

In view of the characteristics of high salinity of injected water,high reservoir temperature and multiple reservoir layers in Block G of Dagang K Oilfield,experiments were conducted to screen temperature⁃resistant and salt⁃tolerant polymers and surfactants.On this basis,the oil displacement efficiency of polymer solutions and polymer⁃surfactant binary composite flooding systems(hereinafter referred to as polymer/surfactant binary flooding systems) was investigated using multi‐layer core models.The results show that among the three types of polymers,hydrophobically associating polymers exhibit superior viscosity enhancement. Compared with HSY and DWS,the polymer/surfactant binary flooding system formulated with DG‐1 surfactant can reduce the interfacial tension to 10⁻³ mN/m.Under the same model layer combination,the incremental oil recovery of the polymer/surfactant binary flooding system is higher than that of the polymer solution;in particular,the incremental oil recovery of the binary flooding system is 1.43% higher in the three‐layer model with a permeability ratio of 10. Under the same flooding agent condition,the mass fraction and viscosity of polymer and surfactant in the produced fluid increase with the increase of model permeability ratio.At the same permeability ratio,a larger number of model layers leads to higher waterflooding recovery,lower chemical flooding and subsequent waterflooding recovery,while the ultimate oil recovery is similar.

Polymer composites are the primary materials for water-lubricated bearings owing to their superior wear resistance, low friction coefficient, and resistance to water and corrosion. Their performance directly governs the safety, reliability, and operating costs of the bearing systems. This paper provides a systematic review of the properties of commonly used polymer composites for water-lubricated bearings and recent research progress. It focuses on analyzing the load-carrying capacity, wear resistance, and frictional behavior of different materials, while comparing their relative advantages and limitations. Finally, by addressing the current challenges with existing materials, the review proposes future research directions for high-performance water-lubricated bearing materials and suggests strategies for optimizing their design and engineering applications, aiming to offer valuable insights for further development.

Transition metal sulfides are known for their high conductivity and theoretical lithium storage capacity,making them promising materials for phase change lithium storage.However,their cycling stability needs improvement.A simple electrostatic spinning method was used to prepare composites with in situ growth of cobalt-based zeolite imidazolite backbones(Co-ZIFs) on electrostatically spun fibers,and the stabilized structure of microzonated ZIFs was exploited to achieve spatially confined domains of metal particles in an N_? heat treatment. Cobalt sulfide/carbon fiber composites (CoS/CFs) were then synthesized through a sulfidation reaction.X-ray diffraction (XRD) and Raman spectroscopy confirmed the uniform distribution of CoS particles on the carbon nanofibers.The optimized composite showed excellent lithium storage performance,maintaining a specific capacity of 584.5 mA·h/g after 250 cycles at a current density of 1 A/g.This demonstrates outstanding cycling stability and suggests promising applications in lithium storage.

Estuary bar sandstone body is also one of the most important types of oil and gas reservoirs in China,and its internal interlayers control the distribution and movement of fluid inside the reservoir and affect the overall development effect of the reservoir. Taking the fault block reservoir of Sha-2（S2） member of L11 fault block in Shinan oilfield as an example, the rock and layer type of intercalation in estuary bar sandstone body are analyzed by means of logging, core, analysis and dynamic production data, the spatial distribution law of intercalation is described, and the influence of intercalation on remaining oil distribution is expounded.The results show that the main oil layer of L11 fault block consists of mud, physical and calc interlayers, which account for 68%,21% and 11% respectively.The calc interlayers are concentrated in the distribution area of physical interlayers,and the development degree of physical interlayers is relatively high in the northeast near the provenance and the peak of the interlayer, while the development degree of mud interlayers is relatively high in the southwest far from the provenance. In the near-source direction, the fifth-order configuration interface is relatively thin, and in the far-source direction, the thickness is relatively thick, ranging from 0.60 m to 29.00 m. In the fourth-order interface, the drilling rate of interlayer is above 60%, the thickness is between 0.35 m and 4.10 m, and the inclination is less than 2.0°. The level 3 interfacial interlayer is spread no more than 3 well spacing, the thickness is less than 1.50 m, and the dip angle is 2.7° on average. Level 4 and 5 interfaces control the distribution of remaining oil,level 3 interface has little influence on the distribution of remaining oil, low injection and high production mode development effect is relatively good,high injection and low production mode development effect is relatively poor,through the injection and production mode can improve the well group oil displacement efficiency and development effect.The above results and understanding have important guiding significance for the efficient development of estuary bar sandstone reservoir.

Perovskite photovoltaic cells are considered as the most promising third generation photovoltaic products due to their high photoelectric conversion efficiency and flexible processing while the high temperature encapsulation process of traditional encapsulation materials can hardly meet the demand of high performance of perovskite photovoltaic modules.In this paper, an adhesive film material by free radical co?polymerization process was successfully synthesized.Light transmission and bonding are characterized by infrared spectroscopy and tensile testing machine,confirming that the polymer is very suitable for chalcogenide photovoltaic cell encapsulation,and that the polymer can be effectively adhered to the chalcogenide solar cell and the outer layer of the glass at 80 ℃.The polymer is suitable for the encapsulation of chalcogenide photovoltaic cells.The photoelectric conversion efficiency of the encapsulated PSCs can reach 20.59%,and the encapsulated PSCs devices show good impact resistance.

Highstrength polymer materials with excellent mechanical properties and wear?resistance have been widely used in water pumps, electric generator and other fields as a new generation of bearing materials. A high performance polyurethane/carbon fiber composite （PUE/CF） was prepared by combining chopped carbon fiber (CF) with polyurethane elastomer (PUE), and the effects of carbon fiber content on the mechanical and tribological properties of the composites were investigated. The results show that the hardness of the composite can reach 60 ~ 68 HD, the tensile strength and elongation at break can reach 54 MPa and 298% respectively. Under dry friction condition, 0.16 of friction coefficient and 0.570% of wear rate can be obtained. Under water friction condition, 0.02 of friction coefficient and 0.129% of wear rate can be obtained. In summary, the composite prepared in this paper can meet the application requirements of polymer bearing bush and have broad application prospects in the field of automobile and ship.

In recent years, the global market demand for pressure?sensitive adhesives has shown a steady growth trend. The market demand has reached about 3.5 million tons in 2021, and the estimated size of the global pressure?sensitive adhesive market in 2025 is ＄10 billion. Amid the development of pressure?sensitive adhesive technology and the increase in the application demand for pressure?sensitive adhesives, functionally modified pressure?sensitive adhesives have become a major trend in this field. Acrylate?based pressure?sensitive adhesive is the most widely used pressure?sensitive adhesive at present. Its performance has been improved after modification. Nevertheless, the modification process has some disadvantages, such as environmental pollution and low resource utilization. Since rubber has the advantages of low cost, superb mechanical properties, high and low temperature resistance, and environmental friendliness,and so on.Rubber?modified acrylate?based pressure?sensitive adhesives have become a development trend in this field. This paper summarized the development process of rubber?modified acrylate?based pressure?sensitive adhesives and outlined and compared the types of rubber and the advantages and disadvantages of modified products.