Abstract: A combined remediation method of petroleum-contaminated soil includes: impurity removal pretreatment, photocatalytic pre-oxidation, stepwise thermal desorption of petroleum from soil, and high-temperature oxidation; with iron-titanium composite metal oxide (ITCMO) as a catalyst, conducting oxidation pretreatment under light conditions so that some cross-linked structures in macromolecular petroleum contaminants are broken and degraded; and conducting stepwise pyrolysis to achieve a removal rate of more than 98.00%. The new method adopts a combined remediation technology of photocatalytic pre-oxidation-stepwise pyrolysis, which realizes a relatively-high removal rate of petroleum hydrocarbons and the efficient and harmless remediation of high-concentration petroleum-contaminated soil, and remedied soil can be reused.

Abstract: A composite nitrogen huff and puff method for a bounded fault block reservoir comprises: selecting the reservoir to be developed, wherein the reservoir to which the development method is applicable is roughly screened according to the following conditions: the reservoir is a bounded fault block reservoir, buried depth<5000 m, residual oil saturation>0.5, reservoir thickness>10 m, horizontal permeability>100 mD, vertical permeability to horizontal permeability ratio>0.35, reservoir porosity>0.20, and stratigraphic dip>8°; and sequentially performing the following huff and puff phases: a nitrogen huff and puff phase, a nitrogen and water composite huff and puff phase, a nitrogen and foaming agent composite huff and puff phase, and a nitrogen and carbon dioxide composite huff and puff phase.

Abstract: A primary heating band is applied to a weld to control a microstructure and hardness of the weld and uniformity of the structure to realize micro-control of the residual stress; an auxiliary heating band is applied a certain distance away from the weld to generate compressive stress on an inner surface of the weld to realize macro-control of the compressive stress. Reinforcement with a rib plate is eliminated, and a labor intensity and a construction period are reduced. The method reduces deformation near the weld and transfers the largest deformation to a non-weld zone; by applying the auxiliary heating and strictly controlling a time interval between primary heating and auxiliary heating, the structure is improved and the welding residual stress is controlled at the same time; a local heat treatment effect is optimized, and a small tensile stress or compressive stress is generated on the inner surface of the weld.

Abstract: The invention relates to the field of drilling fluid, in particular to a saturated salt water drilling fluid of salt response type intelligent polymer and preparation method thereof. The drilling fluid contains two or more of the following components stored in admixture or separately: bentonite, NaOH, KCl, calcium carbonate, barite, NaCl, supramolecular fluid loss additive, supramolecular shear-enhancing agent, plugging agent, coating agent and water. The drilling fluid provided by the invention has the characteristics of salt response and self-assembly, can keep rheological properties such as rapid recovery of the sheared structure, low extreme high shear rate viscosity, good shear dilution property and the like in a high-salt environment, has good fluid loss reduction performance, reservoir protection performance and debris dispersion inhibition performance, and has good temperature resistance and pollution resistance performance.

Abstract: A single-point dual sensor-based leakage method and system for a gas-liquid stratified flow pipeline includes a single-point dual sensor-based leakage formula for a pipeline to be detected; installing two sensors at the same point of one end of the pipeline, a signal collected by the bottom sensor being an acoustic wave propagated by liquid in the pipeline, and a signal collected by the top sensor being an acoustic wave propagated by gas in the pipeline; processing the two acoustic waves to obtain a time difference; and substituting the acoustic velocity in a gas and the time difference into the single-point dual sensor-based leakage formula. The installation of sensors at two ends of a pipeline, avoids missing detection of leakage acoustic wave signals by a single sensor, reduces the number of installed sensors, and is low in cost, high in safety and strong in applicability to a gas-liquid stratified flow pipeline.

Abstract: The invention relates to the recovery of heavy oil reservoirs, and more particularly to a supported catalyst-assisted microwave method for exploiting a heavy oil reservoir. The method includes: (1) injecting a slug of a supported catalyst fluid into the heavy oil reservoir; (2) placing a microwave generator in the heavy oil reservoir to perform volumetric heating on an oil layer containing the supported catalyst fluid; and (3) turning off the microwave generator and injecting water into the heavy oil reservoir for subsequent displacement, where a water injection rate is 3 m/d or less.

Abstract: A laboratory device for simulating the cement sheath consolidation in the frozen soil strata includes the main body, the pressure system and the measuring system. The main body includes the fixing plate, the detachable plate and the base plate. The circular hole is provided in the center of the base. The central column or the heat insulating casing is mounted on the base through the circular hole. The fixing plate, the detachable plate, the base plate and the central column or the heat insulating casing form a cavity for preparing the core and the cement sheath. During use, the device is placed in a low temperature context, and then the frozen soil core with a hollow cylinder can be artificially fabricated. Further, the heat insulating casing holder is placed, and the cement is added to simulate the state of the cement sheath consolidation under the actual strata conditions.

Abstract: Preparation methods of a high modulus carbon fiber (HMCF) and a precursor (mesophase pitch (MP)) thereof are provided. The preparation method of MP includes: separating components with a molecular weight distribution (MWD) of 400 to 1,000 from a heavy oil raw material through size-exclusion chromatography (SEC); subjecting the components to ion-exchange chromatography (IEC) to obtain modified feedstock oil, where, the components are passed through macroporous cation-exchange and anion-exchange resins in sequence to remove acidic and alkaline components; and subjecting the modified feedstock oil to thermal polycondensation and carbonization to obtain high-quality MP with prominent spinnability. With high mesophase content, low softening point, low viscosity, and prominent meltability and spinnability, the obtained MP is a high-quality raw material for preparing HMCFs. The obtained MP can be subjected to melt spinning, pre-oxidation, carbonization, and graphitization to obtain an MP-based HMCF.

Abstract: The present disclosure discloses a core-shell structured NiSe2@NC electrocatalytic material having a general formula of NiSe2@NC. The present disclosure also provides a preparation method and use of the catalytic material. In the present disclosure, hydrazine hydrate is used as a reducing agent, selenium powders are used as a source of selenium, and a metal-organic framework (MOF) is used as a precursor. Selective selenization of mixed-linker MOFs based on mixed ligands is carried out through a hydrothermal reaction. Then, a series of adjustable N-doped carbon-coated NiSe2 nano-octahedrons are prepared through a one-step calcination reaction. By adjusting the types of mixed ligands in the MOF, carbon-coated nickel diselenide composites doped with different pyridinic-N contents can be obtained. Corresponding electrochemical tests prove that, the electrocatalytic activity has a strong correlation with the content of pyridinic-N.

Abstract: The present disclosure relates to the technical field of artificial cores, in particular to a preparation method of artificial sandstone and/or conglomerate core based on lithology and permeability control. The method comprises the following steps: mixing and molding sand particles and a cementing agent in sequence, and further adding a curing agent for performing solidification to prepare the artificial sandstone and/or conglomerate core; wherein composition of the sand particles is determined according to properties of the artificial sandstone and/or conglomerate core comprising lithology and permeability. The present disclosure combines the properties of the artificial sandstone and/or conglomerate core with the proportion of the sand particles, particularly regulates and controls the composition of the sand particles according to the lithology and permeability of the artificial sandstone and/or conglomerate core, thereby performing precise control on the artificial sandstone and/or conglomerate core.

Abstract: A pH sensitive water-absorbent resin suitable for oil well cement slurry and an application thereof are provided. The pH sensitive water-absorbent resin includes distilled water, a monomer, a mixed auxiliary agent, a crosslinking agent and an initiator, the amount of the monomer is 30% to 100% of the mass of the distilled water, the amount of the mixed auxiliary agent is 16% to 67% of the mass of the monomer, the amount of the crosslinking agent is 0.2% to 1% of the mass of the monomer, and the amount of the initiator is 0.4 to 1% of the mass of the monomer.

Abstract: The present invention relates to a lining material of a nonmetal flexible composite pipe and a preparation method. The lining material consists of the following components in the following proportions: 89.5-99.4 wt % of a polymer matrix, 0.5-10 wt % of inorganic particles and 0.1-0.5 wt % of an antioxidant. The preparation method comprises the following steps: (1) preparation of raw materials: raw materials are weighed in a mass ratio for later use; (2) compounding and plasticizing: inorganic particles, a polymer matrix and an antioxidant are added into a twin-screw extruder or a mixer at an extruding or mixing temperature of 190-360° C., and extruded and cooled for later use; and (3) pelleting: the materials after the compounding and plasticizing obtained in the step (2) are pelleted in a pelletizer to obtain the lining material of a nonmetal flexible composite pipe.

Abstract: The attenuation material composition disclosed in the present disclosure comprises a room temperature vulcanized silicone rubber, an epoxy resin, a first curing agent and a second curing agent, wherein the first curing agent comprises ethyl orthosilicate and dibutyltin oxide; and the weight ratio of the room temperature vulcanized silicone rubber to the epoxy resin is (0.1-1):1.

Abstract: A method for evaluating brittleness of a deep shale reservoir and a computer readable storage medium. The method includes determining a Rickman brittleness index of the deep shale reservoir and determining an effective pressure of the deep shale reservoir according to a pore pressure and an overlying formation pressure of the deep shale reservoir. The Rickman brittleness index is adjusted to obtain the brittleness index of the deep shale reservoir according to an exponential relationship of the brittleness index with the effective pressure of the deep shale reservoir. Inherent properties, such as rock brittle mineral content and the like, are better indicated by the Rickamn brittleness index, and then the brittleness index of the deep shale reservoir is obtained by utilizing the exponential relationship of the brittleness index with the effective pressure of the deep shale reservoir, to realize reasonable evaluation for the brittleness of the deep shale reservoir.

Abstract: The present invention relates to the field of natural gas production, and discloses a well structure for natural gas hydrate production, which comprises: a natural gas production well (12); an injection well (4) capable of extending into a geothermal reservoir and injecting a heat-carrying fluid; a high curvature connecting well (7), the inlet end of the high curvature connecting well (7) is connected to the outlet end of the injection well (4); a hydrate production horizontal well (10), which may be arranged in a shallow hydrate reservoir (9), the high curvature connecting well (7) and the hydrate production horizontal well (10) are connected by an ascending well section (8), and connected with the natural gas production well (12). With the above technical scheme, the high curvature connected well connecting the horizontal well and the vertical well can be located in the bottom layer below the hydrate reservoir, enhancing the stability and production efficiency of the gas hydrate production well.

Abstract: The present invention belongs to the field of geophysical exploration, and discloses physical seismic simulation test apparatus and method based on reflected wave field for a hydrate formation. The apparatus comprises a hydrate preparation device and a reflected acoustic wave test device, wherein the hydrate preparation device is configured to generate simulated hydrates, and the reflected acoustic wave test device is configured to continuously emit ultrasonic waves to the simulated hydrates in the generation process, process the received reflected waves to identify and extract reflection characteristic information and acoustic wave velocity change information, and continuously monitor the degree of saturation of the simulated hydrates at the same time to obtain a corresponding relationship between the reflection characteristic information and acoustic wave velocity change information and the degree of saturation of the simulated hydrates.

Abstract: The present application provides a horizontal well multi-section multi-stage reciprocating fracturing method and apparatus. The method comprises the steps of: dividing a fracturing tubular column into n fracturing sections; fracturing the first fracturing section to form a first first-stage fracture; fracturing the second fracturing section to form a second first-stage fracture; fracturing the first fracturing section again to form a first second-stage fracture; going on in this way, fracturing the nth fracturing section to form an nth first-stage fracture; fracturing the (n?1)th fracturing section again to form an (n?1)th second-stage fracture; going on in this way, at last, fracturing the nth fracturing section again to form an (n)th-stage fracture. The present method and apparatus can effectively eliminate or reduce the interference of relatively long fractures that has been generated during the horizontal well multi-section fracturing to fractures generated by subsequent fracturing.

Abstract: The present disclosure provides a multi-path combined high-low voltage plasma rock-breaking drill bit, drill bit apparatus and drilling method. The multi-path combined high-low voltage plasma rock-breaking drill bit comprises: a drill bit body, insulators, plasma generators, drilling fluid outlets, plasma integrated pipelines, a drilling fluid pipe; wherein a plurality of plasma generators are distributed on the same drill bit body; the axis of the plasma generator and the axis of the drill bit body form a certain included angle; each of the plasma generators is independently connected to the ground through its respective plasma integrated pipeline and operates independently; and drilling fluid flows out of the drilling fluid outlets, takes away the heat generated by the operation of the plasma generators, thereby cooling the plasma generators.

Abstract: Disclosed belongs to the technical field of oil and gas field development engineering, and particularly relates to a super heavy oil development method for strengthening an SAGD steam chamber to break through a low physical property reservoir. The super heavy oil development method for strengthening the SAGD steam chamber to break through the low physical property reservoir includes the following steps: (1) selection of a developed oil reservoir; (2) well distribution; (3) steam chamber forming; (4) steam chamber expansion; (5) steam chamber strengthening. The method may enhance the ability of the steam chamber to break through the low physical property reservoir, enlarge the development height of the steam chamber, and further improve the SAGD development effect of super heavy oil.

Abstract: The present disclosure provides a preparation method of an environment-friendly high-temperature resistant water-based drilling fluid plugging anti-sloughing agent, the preparation method comprises the following steps: mixing and emulsifying a styrene monomer, an acrylic monomer and an emulsifier MS-1 aqueous solution to prepare a pre-polymerization emulsion; dispersing hydrophilic monomer, cationic monomer and an emulsifier MS-1 in water, adjusting the pH to be within a range of 6.5-8.