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The challenge associated with depositing high-strength steel using the arc deposition method lies in the propensity for hardened microstructures to form during the deposition process. This hardened microstructure can lead to a decrease in material toughness and potentially cause cold cracks. Fortunately, oxide metallurgy technology is expected to address this issue. Specifically, nano oxides can refine the grain and induce the formation of intracrystalline ferrite, thereby enhancing steel's toughness. To gain a deeper understanding of this process, a study was conducted on the morphology and structure of oxygen-containing second-phase particles generated in parts made from H13 steel wire modified with Al2O3, TiO2, and SiO2. Additionally, the impact of these oxygen-containing second-phase particles on microstructure transformation was investigated. The following conclusions were drawn from the study: (1) The arc's high temperature causes complex reactions among the oxides in the molten pool, ultimately resulting in the formation of oxygen-containing second-phase particles with a unique core-shell structure. The size and composition of these particles vary within the interdendritic and intradendritic regions due to element segregation. (2) Through in-situ observations, this study discovered that oxygen-containing second-phase particles promote the nucleation of high-temperature ferrite and austenite. This promotes grain refinement and induces the formation of intracrystalline ferrite, which positively impacts material toughness. (3) The driving force for ferrite phase transformation induced by oxygen-containing second-phase particles may stem from the Mn-depleted zone surrounding the particles and the low mismatch between the VC outer layer of the particles and the ferrite.

Modulating Tankyrases (TNKS), interactions with USP25 to promote TNKS degradation, rather than inhibiting their enzymatic activities, is emerging as an alternative/specific approach to inhibit the Wnt/β-catenin pathway. Here, we identified UAT-B, a novel neoantimycin analog isolated from Streptomyces conglobatus, as a small-molecule inhibitor of TNKS–USP25 protein–protein interaction (PPI) to overcome multi-drug resistance in colorectal cancer (CRC). The disruption of TNKS–USP25 complex formation by UAT-B led to a significant decrease in TNKS levels, triggering cell apoptosis through modulation of the Wnt/β-catenin pathway. Importantly, UAT-B successfully inhibited the CRC cells growth that harbored high TNKS levels, as demonstrated in various in vitro and in vivo studies utilizing cell line-based and patient-derived xenografts, as well as APCmin/+ spontaneous CRC models. Collectively, these findings suggest that targeting the TNKS–USP25 PPI using a small-molecule inhibitor represents a compelling therapeutic strategy for CRC treatment, and UAT-B emerges as a promising candidate for further preclinical and clinical investigations.

The surfacing layer of cobalt-based alloy is prepared using the tungsten inert gas welding (TIG) process and employing the UMCo50, ST1 and ST6 filler materials. The metallographic testing, hardness, wear and corrosion testing of different surfacing layers have been carried out. Each area of the surfacing layer is characterized using the optical and scanning electron microscope (SEM). Cellular and a few columnar dendrites have been observed near the fusion line of the UMCo50 surfacing layer, and cellular structure is observed in the central region. Dendrites and cellular crystals have been observed in the ST1 and ST6 surfacing layers. The average hardness of UMCo50, ST1 and ST6 surfacing layers are 320 HV, 672.3 HV and 497.5 HV, respectively. The wear loss of the ST1, ST6 and UMCo50 surfacing layer is 2.71 mg, 4.35 mg, and 14.57 mg, respectively. The corrosion weight loss of the ST1, ST6 and UMCo50 surfacing layers are 0.0388 g, 0.0477 g and 0.0833 g, respectively.

Shale oil is of interest for unconventional oil and gas exploration and development and has abundant geological reserves. Shale reservoirs contain numerous nanopores. Understanding the adsorption state of shale oil in the nanopores of shale is beneficial to improve the recovery of shale oil. In this study, the adsorption properties of shale oil in kaolinite slit pores were investigated by molecular dynamics simulation. In order to study the adsorption characteristics of shale oil with different components, a single-component model from n-C8 to n-C15 was established, and a mixed model of n-C8 and n-C15 with different mass ratios represented different crude oil components. The results show that the adsorption capacity per unit area increases with the increase of the alkane carbon number. The adsorption capacity of alkanes on the surface of silicon-oxygen tetrahedron is greater than that on the surface of aluminium-oxygen octahedron. The interaction force between kaolinite and alkane surface increases with the increase of alkane carbon number. The alkane adsorption capacity of silicon-oxygen tetrahedron is stronger than that of aluminium-oxygen octahedron. Competitive adsorption also exists between alkane molecules. Alkanes with higher carbon numbers are more easily adsorbed on the surface of kaolinite. Light alkanes are more likely to exist in free form than heavy alkanes. Based on molecular simulations, we studied the adsorption capacity of alkanes with different carbon numbers and calculated the adsorption capacity per unit area in the pores. It provides a theoretical basis for the calculation of shale oil geological reserves.

Ti is a very important active element in brazing SiO2 ceramics by using Ag-based fillers. Therefore, a density functional theory (DFT) study was applied to investigate the influence of Ti dopant on the interfacial bonding properties of the SiO2 ceramic/Ag interface. Firstly, we built SiO2(0001)/Ag(111) interface with very small lattice misfit. The interface structure with O1 termination and hollow site was found to have maximum value of work of adhesion (Wad). Then, the Ti atoms were doped into the interface at different locations to simulate the possible diffusion sites. The energy results show that Ti atom in the Ag slab was more likely to move to the interface and form bonding with O atoms. The result supports the interface structure of SiO2/Ti-O compounds/Ag. When the coverage of Ti atoms at the interface was raised to 100%, Wad of the interface can reach as large as 16.34 J/m2. The electronic structure analysis indicates that Ti atom at interface can form strong ionic bonding with O atoms. With the increase of Ti atoms, the single Ti-O bonding is weakened with less charge transfer. However, the number of Ti-O bonding increases and the interfaces are strengthened further.

According to the downhole temperature filed, the mechanical behavior of TWIP steel for expansion tube was studied in the temperature range from 25°C to 300°C. Meanwhile, the phase and microstructure changes before and after deformation were investigated by X-ray diffractometer (XRD), optical microscope (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results indicate that yield strength, tensile strength and elongation decrease with temperature increasing. The TWIP steel is single-phase of austenite before and after deformation. Analysis on the microstructure shows that the deformation twins gradually decrease with increasing temperature. The deformation process cannot benefit from the deformation twins, which is responsible for the decreased ductility. In addition, due to the increased temperature, the stacking fault energy becomes high enough to restrain twinning, thus dislocation glide becomes the main deformation mechanism.

Wettability plays a significant role in the exploration and development of shale oil. The wettability affects the oil enrichment and restricts the selection of fracturing fluids. Shale is composed of complex minerals and organic matter. The pores composed of inorganic minerals have water wettability, while the pores composed of organic matter show the characteristics of oil wetting. The contact angle experiment and the spontaneous imbibition experiment are the most commonly used methods for characterizing wettability. The Qingshankou Formation in the Songliao Basin has thick source rocks, which is a favorable interval for shale oil exploration and development. Strengthening the wettability research in this area is of great significance for the exploration of shale oil. The wettability of different lithofacies shale in the northern Songliao Basin is seldom characterized, and there is a lack of comparative studies on contact angle and imbibition characteristics. In view of this situation, the shale of the Qingshankou Formation in the northern Songliao Basin has been classified. This article used the method of spontaneous imbibition combined with nuclear magnetic resonance to characterize the wettability of shale and analyze the influencing factors of the wettability of different shale lithofacies. Six samples with different lithological characteristics were used for this experiment. The study found that the imbibition results of samples with different lithofacies are different. The imbibition of sandy interlayer is less affected by the direction, while the imbibition of shale is more affected by the direction. The water imbibition volume of the sample is related to the content of clay minerals. The relationship of water imbibition volume in different lithofacies samples is as follows: low organic matter laminated siliceous shale > high organic matter massive clay shale > sandy interlayer > high organic matter laminated siliceous shale > high organic matter massive siliceous shale. Excessive content of clay minerals will cause shale to absorb water and expand and block pores, which is not conducive to further water imbibition by shale. The volume of oil imbibed is related to the organic carbon content. The relationship of oil imbibition volume in different lithofacies samples is as follows: high organic matter massive clay shale > high organic matter laminated siliceous shale > sandy interlayer > low organic matter laminated siliceous shale > high organic matter massive siliceous shale. The higher the total organic carbon content, the more developed the lipophilic pore network, and the more the volume of oil imbibed by the sample.

Hybrid sedimentary rocks (HSR) are a major reservoir type in unconventional oil exploration. The reservoir characteristics and controlling factors of the oil content of HSR are not clear, restricting the understanding of the storage mechanism and sweet spots within HSR. The Lucaogou Formation in the western Jimusar Sag is taken as a case study. Starting with the classification of the lithofacies system, differences in the microscopic pore structure, oil content and controlling factors of HSR reservoirs are revealed. The results show that seven lithofacies are recognized based on mineral composition, sedimentary structure, and organic matter characteristics, exhibiting rapid vertical and horizontal changes affected by the sedimentary environment. Layered mudstone lithofacies of the shallow lake mud and massive dolomitic mudstone lithofacies of dolomitic mud flats have the worst physical properties and oil content properties. However, they do have high organic matter contents and are the main source rocks of the Lucaogou Formation. The massive argillaceous siltstone and massive argillaceous dolomite lithofacies interbed frequently. Although their physical properties are moderate, “source-reservoir integrated” unconventional oil reservoirs can be formed, due to the adjacent to the source rock. Massive dolomitic siltstone, massive siltstone, and massive silty dolomite lithofacies are developed in the middle of the Lucaogou Formation, with the highest proportion of mesopores and macropores, which is indicative of good storage properties. When these lithofacies are filled with crude oil generated from source rocks at the top and bottom of the formation, “source storage adjacent” unconventional oil reservoirs be formed. The oil content is also controlled by the pore structure and specific surface area. The proportion of macropores and mesopores is positively correlated with oil content. The oil content of the samples is very low, when the specific surface area exceeds 2 m2/g. This manuscript provides a geological basis for evaluating and establishing reasonable interpretation models of HSR sweet spots.

The Ri-Qing-Wei Basin is a newly discovered Late Mesozoic rift basin on the eastern Shandong coast in recent years. Thick, continuous deposited source rocks are found in the Lingshan Island scientific drilling project. Therefore, it is necessary to evaluate the distribution and hydrocarbon generation potential of source rocks in this area. Organic geochemical experiments were carried out on samples from the core of LK-1 and outcrops in the Lingshan Island, the Laoshan area, and the Jimo Zhougezhuang area to evaluate the maturity, abundance, and type of organic matter in source rocks. The results show that the cumulative thickness of the source rocks in the study area is more than 500 m, and the TOC content is generally greater than 1.0%. The organic matter type is good (mainly type II1 and type II2 kerogen) and the Ro value is more than 2.0. The thermal evolution degree of the organic matter is high with natural gas predominantly generated. We carried out Rock-Eval, PY-GC and gold tube experiments on low-maturity samples of Laikong 2 and established a chemical kinetic model to quantitatively evaluate the study area in combination with sedimentary burial history and thermal history data. The results show that the total resources of the five sags in the study area are about 476 billion cubic meters, and the average resource intensity is about 82.2 million cubic meters/km2. Among them, the resource intensities of the Lingshan Island Sag and Laoshan Sag are 112.6 million cubic meters/km2 and 98.8 million cubic meters/km2, respectively. Studied sites are “small and fertile” and may be used as favorable exploration prospect areas.

Wettability is a significant factor in the exploration and development of shale oil. Currently, shale wettability has yet to reach a unified understanding. The contact angle is widely used in the study of shale wettability. However, the pre-treatment of the shale profoundly affects the contact angle. In this paper, the contact angle errors introduced by the pre-treatment of samples are discussed. Shale wettability is influenced by many factors, and there is not yet a systematic study of its influencing factors. Based on the above issues, the shale of the northern Songliao Basin was taken as the subject. The wettability of the different lithofacies is characterized by an improved contact angle method. The compositional characteristics of the shales and oil in the study area were analyzed. Fresh minerals, a single component of oil, and different temperature/pressure conditions were set up to investigate the influencing factors of shale wettability. The studies show that Organic matter abundance and thermal maturity have a positive correlation with oil-wet. Siliceous minerals are positively correlated with water-wet. Carbonate and clay minerals are negatively correlated with water-wet. The mineralogical composition of the shale, the composition of the oil, the characteristics of the aqueous media, the asphaltene deposits on the surface, temperature, and pressure all impact wettability. The affinity of minerals for hydrocarbons is iron minerals > carbonate minerals > clay minerals > siliceous minerals. Minerals are more hydrophilic at low salinity conditions. The deposition of non-hydrocarbons and asphaltenes renders the surface oleophilic. Increasing temperatures will reduce the hydrophilicity of the “oil-water-rock”.

Owing to the native character of the coefficient of thermal expansion (CTE) mismatch between Al2O3 and 304 stainless steel, obtaining high strength for Al2O3/304 stainless steel joints remains challenging. In this study, the residual stress of an Al2O3/304 stainless steel brazed joint was relieved using the Ag‐Cu‐Ti + boron nitride (BN) composite filler. The results indicated that the elements between the filler and base metals on both sides were mutually diffused. Moreover, reaction layers formed at the interface, connecting the Al2O3 ceramic and 304 stainless steel. The microstructure of the joint was as follows: Al2O3/Cu3Ti3O + TiCu/Ag (s, s) + Cu (s, s) + TiN + TiB2 + TiCu/Cu0.8Fe0.2Ti/TiFe2/Fe‐Cr/304 stainless steel. When the.1 wt% BN was added, the average strength of the joint reached 151 ± 10 MPa, 15% higher than the average strength of the joint only using Ag‐Cu‐Ti filler (131 ± 9 MPa). The improvement in the shear strength and reduction in the residual stress was attributed to the formation of TiN and TiB2, reducing the CTE difference and refining the microstructure. [ABSTRACT FROM AUTHOR]

Hydrocarbon vapor adsorption experiments (HVAs) are one of the most prevalent methods used to evaluate the proportion of adsorbed state oil, critical in understanding the recoverable resources of shale oil. HVAs have some limitations, which cannot be directly used to evaluate the proportion of adsorbed state oil. The proportion of adsorbed state oil from HVA is always smaller than that in shale oil reservoirs, which is caused by the difference in adsorption characteristics of liquid and gaseous hydrocarbons. The results of HVA need to be corrected. In this paper, HVA was conducted with kaolinite, an important component of shale. A new method is reported here to evaluate the proportion of adsorbed state oil. Molecular dynamics simulations (MDs) of gaseous/liquid hydrocarbons with the same temperature and pressure as the HVAs were used as a reference to reveal the errors in the HVAs evaluation from the molecular scale. We determine the amount of free state of hydrocarbons by HVAs, and then calculate the proportion of adsorbed state oil by the liquid hydrocarbon MD simulation under the same conditions. The results show that gaseous hydrocarbons adsorptions are monolayer at low relative pressures and bilayer at high relative pressures. The liquid hydrocarbons adsorption is multilayer adsorption. The adsorption capacity of liquid hydrocarbons is over 2.7 times higher than gaseous hydrocarbons. The new method will be more effective and accurate to evaluate the proportion of adsorbed state oil.

In order to refine the microstructure of Inconel 718 and achieve high performance, nanometer TiO _2 particles (nano-TiO _2 ) were adopted to modify the solidification structure. After pretreating nano-TiO _2 , oxide added 718 nickel alloy were prepared by using arc melting technology, and the microstructure and oxidation behavior were investigated in detail. The results show that the microstructures of Inconel 718 alloys with different content of nano-TiO _2 are all dendritic-like, and the size of dendrite gradually decreases and the shape tends to become equiaxed grain with the increase of TiO _2 content. The grain refinement effect is best for 0.6%TiO _2 added alloy. The precipitated phases become finer and more uniform due to grain refinement. The high temperature oxidation experiments of Inconel 718 alloy with different volume fractions of TiO _2 show that the main oxides are Cr _2 O _3 , accompanying with some Nb-Fe oxides. With the decrease of grain size, the size of oxides gradually decreases, and the oxidation layers are more and more compact, which effectively improves the oxidation resistance.

Abstract: On the basis of the characterization of microscopic pore-throats in shale oil reservoirs by high-pressure mercury intrusion technique, a grading evaluation standard of shale oil reservoirs and a lower limit for reservoir formation were established. Simultaneously, a new method for the classification of shale oil flow units based on logging data was established. A new classification scheme for shale oil reservoirs was proposed according to the inflection points and fractal features of mercury injection curves: microscopic pore-throats (less than 25 nm), small pore-throats (25−100 nm), medium pore-throats (100−1 000 nm) and big pore-throats (greater than 1 000 nm). Correspondingly, the shale reservoirs are divided into four classes, I, II, III and IV according to the number of microscopic pores they contain, and the average pore-throat radii corresponding to the dividing points are 150 nm, 70 nm and 10 nm respectively. By using the correlation between permeability and pore-throat radius, the permeability thresholds for the reservoir classification are determined at 1.00× 10−3 μm2, 0.40×10−3 μm2 and 0.05×10−3 μm2 respectively. By using the exponential relationship between porosity and permeability of the same hydrodynamic flow unit, a new method was set up to evaluate the reservoir flow belt index and to identify shale oil flow units with logging data. The application in the Dongying sag shows that the standard proposed is suitable for grading evaluation of shale oil reservoirs. Key words: shale oil, microscopic pore-throat, high pressure mercury injection, lower limit of reservoir formation, grading evaluation, Bohai Bay Basin, Dongying sag

Taking the southern Songliao Basin as the target area, the hydrocarbon expulsion volume from source rocks has been quantitatively evaluated in this paper, based on the material balance method. Employing the “Overpressure” module of PetroMod software, the overpressure history of the source rocks was evaluated. According to the relationships between hydrocarbon expulsion rate, residual organic carbon content and overpressure within the source rocks, the lower limits of expulsion from tight oil source rocks were determined: a hydrocarbon expulsion amount of 2 mg/g, residual hydrocarbon content of 0.8%, and overpressure of 1 MPa. The source rocks with hydrocarbon expulsion amounts > 8 mg/g, a residual organic carbon content > 2.0%, and overpressure > 7 MPa were defined as excellent source rocks. As a result, tight oil source rocks can be divided into three types, excellent source rocks (type I), inefficient source rocks (type II) and non-productive source rocks (type III). The actual application in the southern Songliao Basin shows that the excellent source rocks have an obvious control on the planar and vertical distribution of tight oil discoveries, areas with excellent source rocks and nearby formations are favorable for the accumulation of tight oil. Key words: tight oil, source rocks, grading evaluation, hydrocarbon expulsion, overpressure, southern Songliao Basin

In this study, the effects of Ti and Ce on the microstructure, corrosion behavior and rust resistance of invar alloys were investigated in detail. The precipitation phase which can be used as the core of heterogeneous nucleation can be formed by adding an appropriate amount of Ti and Ce, which promotes microstructure refinement and homogenization of the invar alloy. Moreover, the electrochemical behavior of invar alloys with different Ti and Ce contents was studied. The results show that with the addition of alloying elements, the self-corrosion potential of the alloy becomes positive, and the self-corrosion current decreases, indicating that the addition of Ti and Ce is beneficial for improving the corrosion properties of the alloy. This is primarily because Ti and Ce combine easily with unfavorable elements to form precipitates, which reduces the factors affecting the corrosion resistance of the alloy. The invar alloy with superior corrosion resistance was selected for the dipping test. X-ray diffraction analysis showed that the addition of Ti and Ce increased the amount of α -FeOOH and enhanced the protective effect of the antirust layer.

Fine oxide particles can play a role in refining grains and promoting nucleation in steel. In this research, a solid welding wire containing nanosized oxides was obtained by preparing a ‘master alloy’. The oxide size was studied by optical microscopy, scanning electron microscopy and transmission electron microscopy. The results show that micron-sized oxides were crushed into nanosized particles under thermal shock in the welding wire steel smelting process. The mechanical properties of deposited metals were studied by tensile and Charpy impact tests. The results demonstrate that the low-temperature impact toughness of deposited metal is effectively improved by adding oxides to wires. When the oxide content was 1%, the impact absorbed energy was 59 J at −40 °C. Compared with that of the deposited metal without oxides, the impact absorbed energy increased by 22.92%. The addition of oxides refines the original austenite grains and promotes acicular ferrite nucleation so that the deposited metal has better mechanical properties. To obtain good strength toughness matching, the welding wire with 1% oxides has the best comprehensive properties.

In order to solve the problem of the failure of the UMCo50 process burner, the orthogonal test was used to optimize the UMCo50 cobalt-based alloy TIG surfacing process, better joint performance was obtained for welding current of 120 A, surfacing speed of 12 cm min ^−1 , interpass temperature of 50 °C and surfacing layer of 2 ∼ 3 layers; Tungsten inert gas(TIG) welding and plasma transferred arc weld(PTAW) surfacing were used to surfacing UMCo50 welding wire and T800 cobalt-based alloy powder on UMCo50 base metal. The structure, hardness, high temperature wear resistance and heat corrosion resistance of the surfacing layer were compared. The results show that UMCo50 surfacing layers are α -Co (fcc) and ε -Co (hcp); T800 alloy surfacing layers are mainly Co _3 Mo _2 Si, CoMoSi, α -Co and ε -Co. The Laves phase in the T800 alloy surfacing layer significantly improves its hardness and high temperature wear resistance; Under the same test conditions, the heat and corrosion resistance of the UMCo50 surfacing layer is significantly better than that of the T800 surfacing layer.

High frequency supercapacitors (HFSCs) are promising in alternating current line filtering and adaptable storage of high-frequency pulse electrical energy. Herein, we report a facile yet integrated-circuit-compatible fabrication of HFSC electrodes by combining chemical roughening of the sputtered metal (Au) films and in situ trace loading of a pseudocapacitive material (MnOx). The developed electrode fabrication route is versatile for different substrates, and is described with the application paradigms of both on-chip (with Si/SiO2 substrate) and off-chip (without Si/SiO2 substrate, with Ti substrate as an example in this study) HFSCs. With Au/MnOx films on Si/SiO2 substrates as the working electrodes, the derived on-chip HFSC displayed satisfactory performance in high frequency applications (i.e., an areal capacitance of 131.7 µF cm−2, a phase angle of −78°, and a RC time constant of 0.27 ms, at 120 Hz).

X-ray computed tomography is an efficient method for quantitatively estimating the characteristics and heterogeneity of shales in three dimensions. A threshold is commonly used to separate pore-fractures from the background image. However, few studies have focused on the multi-component segmentation of computed tomography images. To obtain the distribution characteristics of different components in three dimensions, a segmentation method was proposed that combines a multi-Otsu thresholding algorithm with scanning electron microscopy. The gray value distributions of different components were first determined using this method. Then, the shale components were divided into several groups based on these gray values. The threshold of each component group was determined using the multi-Otsu thresholding algorithm. The computed tomography image stacks of two shale samples were processed using this segmentation method, and another computed tomography image stack was used to verify the method. The results showed that (1) the multi-component segmentation method can successfully segment computed tomography image stacks using the calculated values determined by computed tomography, which agree well with the measured values obtained from X-ray diffraction, total organic carbon, and porosity tests in the laboratory; (2) samples with similar provenances and mineral compositions have the same gray value distribution in the back scattering scanning electron microscopy and computed tomography images; (3) this method is superior in both the effectiveness and efficiency of the computed tomography image stack segmentation of samples according to the gray value distribution, as determined by samples with similar provenances and mineral compositions.

To research the characteristics and petroleum geological significance of micro pores, this paper uses Second Electron Microscope (SEM) and secondary SEM imaging capability in Field Emission SEM (FE-SEM) to characterize shale from the first member of the Cretaceous Qingshankou Formation, Songliao Basin. There are five major pore types in the shale, including matrix intercrystal, organic, dissolution, interparticle, and intracrystalline pores. In addition, there are a mass of micro-fractures of micron-submicron (nano-) scale, including dissolution, filled and interlayer fractures. The existence of complex fracture-pore systems provides an effective pathway for primary migration and it also provides ample storage space for the residual petroleum in shale, which is important for the primary migration and storage for shale oil and gas resources. Key words: Songliao Basin, shale, micro pore structure, micro fracture, reservoir