Shale gas is an important unconventional resource. The economic recovery of shale only possible when a fracture network with sufficient conductivity created by hydraulic fracturing, that, if effectively propped, connects fracturing fractures and natural fractures. Focusing on the Longmaxi in Sichuan Basin, Southwest China, we built optimization model for multi-grade based equivalent seepage theory. We then experimentally analyzed self-propped sand-propped fractures, optimized propping...

The limestone reservoir of the Da’anzhai section is main production layer Jurassic tight oil in central Sichuan, with and strongly heterogeneous rocks. In early stages, small-scale plug removal acidification techniques were mainly applied to dacite reservoir. However, using a single conversion method was not suitable for reservoirs underdeveloped fractures. To address this challenge, we conducted large-scale real-world triaxial simulation test system experiments on hydraulic fracture...

The research provided theoretical guidance and process optimization for CO 2 continuous laser ablation of PMMA sheets, had universality reference value the processing non-metallic polymer materials.

BACKGROUND Orthodontic treatment for open bite and crossbite cases is always challenging. In this paper, we demonstrate a skeletal class III patient with anterior whose problem was successfully corrected improved super-elastic Ti-Ni alloy wire (ISW). CASE SUMMARY A 19 years old male came to our clinic chief complaint of not able chew food well. Clinical examination revealed an angle malocclusion bite, spaced arch. Radiographic clinical showed pattern. We used ISW level the upper lower arch...

The ultradeep carbonate reservoir in Sichuan Basin is characterized by deep burial depth, high temperature, and strong heterogeneity. In the early stage of production, vertical well acid fracturing main stimulation method, horizontal technology not mature enough to release production capacity gas wells. Segmented wells currently faces following problems: heterogeneity leads difficulty fine segmentation; temperature requires higher performance working fluid; reaction rate between rock fast...

The effect of fiber laser welding on solute segregation and proprieties CoCrCuFeNi high entropy alloy was investigated. microstructure mechanical properties the parent metal fusion zone were comparably studied. dendrite, with elemental Cu segregated to interdendrites owing small bonding energies Fe, Co, Ni, Cr atoms. After welding, in center predominantly equiaxial grains, whereas that edge region mainly columnar crystals oriented perpendicular line. is alleviated by grain refinement molten...

Compared to conventional fracturing techniques, foam has numerous advantages, including good shear resistance, strong sand carrying capacity, low fluid loss, damage, and fast return rates. It is particularly suitable for stimulation in pressure, permeability, water-sensitive formations. Specifically, CO 2 crucial energy savings emission reductions, controlling the expansion of reservoir clay minerals, reducing crude oil viscosity, improving production water-locked reservoirs. In this paper,...

Carbonate gas reservoirs in Sichuan are deeply buried, high temperature and strong heterogeneity. Staged acid fracturing is an effective means to improve production. acidizing of ultra-deep horizontal wells faces the following problems: 1. Strong reservoir heterogeneity leads difficulty fine segmentation; 2. The well section long running too many packers increases completion risk; 3. Under temperatures, reaction speed between rock rapid action distance short; 4. fracture conductivity low...

For unconventional oil and gas reservoirs deep carbonate reservoirs, temporary plugging fracturing is an important technology to improve production. At present, the research of mainly focused on development high-performance agent, simulation fracture growth morphology test ability agent. There limited migration law agents in fractures, which affects optimization processes parameters. Through a crack sealing experimental device, taking into account influence rough cracks width, agent pressure...

Coal-assisted water electrolysis (CAWE) technology has garnered significant attention for hydrogen production due to its potential reduce energy consumption. This review introduces the background and importance of CAWE analyzes fundamental electrochemical principles, including direct indirect oxidation pathways involving redox pairs. The process requires only 2.19 kWh/m3 compared >4.1 traditional methods, showcasing savings. discusses research progress challenges in key technologies, such as...

This paper numerically studied the residual stress in a butt-welded steel pipe. A comparison of 3D pipe and axi-symmetric finite element model under condition same welding simulation parameters was carried out. The results showed that axi- symmetric share similar distribution with heat source shape parameters. However, values two concerned models were quite different. Meanwhile scale pool for almost twice bigger than model. Both experiment peak temperature along path increased during...

A heat source model is the key issue for laser welding simulation. The Gaussian not suitable to match actual weld profile accurately. Furthermore, fiber lasers are widely recognized result in good‐quality beam output, a narrower zone, less distortion, and high process efficiency, compared with other types of (such as CO 2 , Nd : YAG, diode lasers). At present, there few models welding. Most researchers evaluate only by bead width depth penetration, which keyhole nail‐like profile. This paper...

Many items of medical, aeronautical, electronic and military equipment are exposed to corrosive conditions, it is a common practice protect these in laser beam welded titanium-alloy micro-packages, which require very small precise weld zones. A range types has been applied this task, including Nd:YAG, diode (more recently) fibre lasers. Compared with other welding (LBW) processes, lasers widely recognised result lower overall heat input, narrower zone, less distortion high process...

The gas and solid residues after coal explosion contain abundant information that can reflect the reaction mechanism hazardous effects of dust explosion. To investigate characteristics products explosion, experiments were conducted in a 20 L spherical vessel. micromorphology chemical functional groups observed by scanning electron microscopy Fourier-transform infrared (FTIR) spectroscopy analysis. Moreover, composition concentration tested chromatography. results indicated with low...