Chemical pretreatment is often used in electroless plating process to enhance the bonding of metallic coating to ceramic substrates. In order to alter the chemical pretreatment which is not suitable ...for local processing and not environmentally friendly for operating personnel, laser surface texturing (LST) was applied in electroless nickel plating on alumina in this paper.
The electroless nickel plating was carried out on alumina surfaces that were either chemically coarsened or laser textured with different pit depths. The morphology of textured alumina surfaces was characterized by optical microscope and 3D laser confocal microscope, while its surface roughness was measured by a TA620 roughness tester. The adhesive performance of nickel coatings was evaluated by indentation and scratch tests.
The results showed that laser surface texturing can improve the adhesive performance of electroless plated nickel coating on the alumina samples. The critical load of the properly laser surface textured samples is more than 2 times of that of the chemically coarsened samples. For the process of electroless nickel plating, laser surface texturing can replace traditionally chemically coarsening pretreatment, which can reduce the contact opportunity with strong acid for operating personnel.
•Laser surface texturing (LST) treatment was used as a new technology to improve adhesion of electroless coating.•LST treatment can improve the adhesion of nickel plating on alumina.•LST treatment can replace the chemical coarsening of traditional pretreatment.
Investigating the deformation mechanism of cataclastic bands in high-porosity sandstone is crucial for understanding the juxtaposition sealing ability of sandstones in a bed sequence. However, ...deformation bands that are developed in the field and rock cores do not reflect the evolutionary history of the host rock; therefore, the continuous deformation of high-porosity sandstone cataclastic bands cannot be observed. This paper analyzes the deformation mechanism that affects a cataclastic band when high-porosity sandstone faults form. Based on the latest independently developed high-pressure/low-speed ring shear experimental apparatus, the formation and evolutionary process of cataclastic bands in high-porosity sandstone were studied through the similarities among artificial cores. During the experiments, the effective normal stresses and fault displacement were used as single variables. After the experiments, plunger samples were drilled in the lateral direction, and thin sections were prepared to observe and analyze the thickness and particle characteristics of the deformation bands, thereby characterizing the deformation process of the damage zone. The experimental results reveal that high-porosity sandstone undergoes different intensities of cataclasis during the shearing process, and the evolutionary characteristics can be divided into four primary stages. The particles in the sandstone are successively subjected to rotation, rolling, cracking, cataclasis, and other changes after forced deformation. In terms of the macrostructure, a deformation band can be divided into two layers: an inner zone and an outer zone. From the host rock and the outer zone to the inner zone, the orientational arrangement of the particles along the shear direction becomes increasingly clear, and a greater displacement indicates a stronger orientational arrangement effect of the particles. In terms of the microstructures, the particle sizes in the deformation band are 2–3 orders of magnitude smaller than those in the host rock and exhibit greater roundness. With increasing shear displacement, the thickness of the cataclastic band first increases and then remains constant. With increasing effective normal stress, the thickness first decreases slightly, then increases and finally decreases slightly. Therefore, stress and displacement are important factors controlling cataclasis. The influence of displacement on cataclasis is clear at the initial stage, and stress determines the maximum intensity of cataclasis. Additionally, the increase in displacement will be favorable for roundness when the host rock is poorly sorted. These experimental results provide a theoretical basis for future studies on the effects of cataclastic bands and fluid flow.
A growing number of studies have focused on investigating circRNAs as crucial regulators in the progression of multiple cancer types. Nevertheless, the biological effects and underlying mechanisms of ...circRNAs in pancreatic ductal adenocarcinoma (PDAC) remain unclear.
Differentially expressed circRNAs between cancerous tissue and adjacent normal tissues were identified by RNA sequencing in PDAC. Subsequently, in vitro and in vivo functional experiments were performed to investigate the functional roles of circNEIL3 in PDAC tumour growth and metastasis. Furthermore, RNA pull-down, dual-luciferase reporter assays, RNA immunoprecipitation (RIP) assays, fluorescent in situ hybridization (FISH) and Sanger sequencing assays were performed to examine the circular interaction among circNEIL3, miR-432-5p and adenosine deaminases acting on RNA 1 (ADAR1).
CircNEIL3 was upregulated in PDAC and promoted the progression of PDAC cells both in vitro and in vivo. Mechanistically, circNEIL3 was shown to regulate the expression of ADAR1 by sponging miR-432-5p to induce RNA editing of glioma-associated oncogene 1 (GLI1), ultimately influencing cell cycle progression and promoting epithelial-to-mesenchymal transition (EMT) in PDAC cells. Moreover, we discovered that the circNEIL3/miR-432-5p/ADAR1 axis was correlated with the PDAC clinical stage and overall survival of PDAC patients, while ADAR1 may reduce the biogenesis of circNEIL3.
Our findings reveal that circNEIL3 facilitates the proliferation and metastasis of PDAC through the circNEIL3/miR-432-5p/ADAR1/GLI1/cell cycle and EMT axis and that its expression is regulated by ADAR1 through a negative feedback loop. Therefore, circNEIL3 may serve as a prognostic marker and a therapeutic target for PDAC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
An understanding of across-fault seals is essential for planning an injection/production strategy for a fault-bounded gas storage site. In addition, it is more likely to permit lateral leakage for a ...fault with sand self-juxtaposition windows. This paper is aimed at identifying the dynamic sealing behaviors of a sand self-juxtaposition fault on the geological and gas injection timescales. Banzhongbei gas storage site, China, was taken as a target area, and fault seals and hydrocarbon distributions within the original reservoirs were studied. The results showed that across-fault pressure differences of 0.085∼0.146 MPa (equivalent to 41.6∼71.5 m oil-column and 27.0∼46.4 m gas-column heights) were supported by sand self-juxtaposition windows on the B816 fault, and the resultant absolute permeability (5.97 × 10-2 ∼ 5.69 × 10-1 mD) of the fault was nearly 3∼4 orders of magnitude lower than the average absolute permeability of reservoirs (1.16 × 102 mD). Gas composition contrasts, between the original and injection gas coupled with dynamic pressure monitoring data, indicated that lateral leakage occurred across sand self-juxtaposition windows under the condition of high across-fault pressure difference. However, the low-permeability fault showed strong negative influence on the efficiency of fluid flow in the model calculations and prolongs the timescales of pressure-difference decayed as much as 5 orders of magnitude relative to those of nonfault model calculations. These modeled dynamic sealing behaviors of sand self-juxtaposition windows may lead to a better understanding of the relative retardation of across-fault gas flow by weak sealing faults on the gas injection/production timescale.
The eastern Liaodong Bay sub-basin is located in the northeastern Bohai Bay basin, where Cenozoic fault patterns are thought to be largely affected by the movement of the Tan-Lu strike-slip fault ...zone. Based on three-dimensional seismic data, we identify the initial timing of faulting on normal faults with various orientations in the eastern Liaodong Bay sub-basin, document the structural features and evolution of the fault system and compare the fault patterns with analog models. The basin experienced phases of extensional, strike-slip and inversion-type deformation from the Paleogene syn-rift stage to the Neogene-Quaternary post-rift stage. During the Eocene, the eastern Liaodong Bay sub-basin was in a nearly NNW-SSE oriented extensional setting, with active faults predominantly trending NE-SW to ENE-WSW. During the Oligocene, the eastern Liaodong Bay sub-basin was in a predominantly dextral strike-slip setting. In the study area, the NE-SW trending boundary faults were reactivated, and the reactivated pre-existing internal faults rotated to a more E-W trend. Some of the newly formed extensional faults were orthogonal to the eastern boundary fault F1 and were oriented NW-SE, while others were predominantly oriented E-W. The renewed minor phase of N–S extension during the Miocene caused the reactivation of some pre-existing faults striking NE-SW (boundary faults) and E-W (internal faults); the faults exhibit a bidirectional character in the post-rift section, and the later inversion caused regional compressional deformation. These results suggest that the reactivation of pre-existing faults under phases of extension, strike-slip and inversion provides a more comprehensive explanation for the fault patterns and anticlines observed in the eastern Liaodong Bay sub-basin.
•Identification of the initial faulting timing of normal faults is used to distinguish fault types.•An en echelon pattern of boundary faults formed under oblique extension.•Rootless flower-like structures developed during the strike-slip stage.•The basin experienced phases of extensional, strike-slip and inversion-type deformation.
circular RNAs (circRNAs) have been reported to play crucial roles in the biology of different cancers. However, little is known about the function of circSTX6 (hsa_circ_0007905) in pancreatic ductal ...adenocarcinoma (PDAC).
circSTX6, a circRNA containing exons 4, 5, 6 and 7 of the STX6 gene, was identified by RNA sequencing and detected by quantitative reverse transcription PCR (qRT-PCR). The biological function of circSTX6 was assessed in vitro and in vivo. The relationship between circSTX6 and miR-449b-5p was confirmed by biotin-coupled circRNA capture, fluorescence in situ hybridization (FISH) and luciferase reporter assays. The interaction of circSTX6 with Cullin 2 (CUL2) was verified by RNA-protein RNA pull-down, RNA immunoprecipitation (RIP) and western blotting assays.
circSTX6 was frequently upregulated in PDAC tissues, and circSTX6 overexpression promoted tumor proliferation and metastasis both in vitro and in vivo. Furthermore, circSTX6 expression was associated with tumor differentiation and N stage. Mechanistically, circSTX6 regulated the expression of non-muscle myosin heavy chain 9 (MYH9) by sponging miR-449b-5p. Moreover, circSTX6 was confirmed to participate in the ubiquitin-dependent degradation of hypoxia-inducible factor 1-alpha (HIF1A) by interacting with CUL2 and subsequently accelerating the transcription of MYH9.
Our findings indicate that circSTX6 facilitates proliferation and metastasis of PDAC cells by regulating the expression of MYH9 through the circSTX6/miR-449b-5p axis and circSTX6/CUL2/HIF1A signaling pathway. Therefore, circSTX6 could serve as a potential therapeutic target for the treatment of PDAC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Based on comparisons between fault growth histories and the distributions of paleo-oil and existing oil accumulations, the fault growth and linkage processes have been proposed as being critical in ...determining the location, timing, and oil preservation of “like-dipping” (with inclinations the same as those of the corresponding strata) and “oppositely-dipping” (with inclinations opposite to those of the corresponding strata) fault-bound traps in the Qi'nan area of the Huanghua Depression in Bohai Bay Basin. The critical fault throw is a key factor determining the leakage behavior and integrity of these traps. “Oppositely-dipping” fault-bound traps are developed at the throw maxima of the footwalls; these throw maxima are located at the trap crests. Once the throw exceeds the threshold, the oil columns in the traps become fully breached (emptied). “Oppositely-dipping” fault-bound traps with preserved oil are found in almost all single-layer systems (either fully preserved or fully breached). However, “like-dipping” fault-bound traps are found where interacting fault segments are hard-linked, and the throw minima are located at the trap crests. A closure bounded by a “like-dipping” reactivated fault might still retain hydrocarbons when the throw of crest is below the established threshold. “Like-dipping” fault-bound traps with preserved oil are found in single-layer and multilayer systems (either partially preserved or partially breached). Therefore, a trap integrity model is constructed on the basis of the aforementioned observations. The results of this model exhibit great consistency with the results derived from 31 drilled fault-bound traps containing petroleum fluid inclusions in the Qi'nan area. The model successfully explains the complex distributions of paleo-oil and preserved oil columns in the “like-dipping” and “oppositely-dipping” faults. In addition, the mechanisms proposed in the model may be applicable to other plays or basins.
1.The critical fault throw was a key factor in determining the leakage behavior. “Oppositely-dipping” fault-bound traps are developed at the throw maxima of the footwall, the throw maxima are located at the crest of trap. Once throw exceed the threshold, the oil columns in the traps become fully breached (empty). Therefore, the “oppositely-dipping” fault-bound traps with preserved oil are almost always found in single-layer systems (either fully preserved or fully breached). The “like-dipping” fault-bound traps are located where interacting fault segments are hard-linked, the throw minima are located at the crest of trap. A closure bounded by a “like-dipping” reactivated fault might still retain the hydrocarbon when the throw of crest is less than the threshold. Therefore, the “like-dipping” fault-bound traps with preserved oil are found in single-layer systems or multilayer systems (partially preserved and partially breached).2.A trap integrity model, comprising a series of temporal and spatial evolution of fault-bound traps and hydrocarbon vertical leakage risk, is constructed, and it effectively explains the reason behind the aforementioned discrepancies. The results of the proposed model have a good degree of consistency with the drilling results from 31 individual fault-bound traps containing petroleum fluid inclusions in the Qi'nan area.
The excavation-loose zone (ELZ) is a key factor for the design and construction of underground engineering. In this study, ground-penetrating radar (GPR), non-invasive and effective method, is ...utilized to estimate the ELZ around an excavated soft coal seam with roof and floor consisting of soft rock seams. The picture segmentation method based on the 2D maximum between-cluster variance is conducted to optimize the radargrams obtained GPR, and then the ELZ can be accurately estimated by analyzing the radargrams. The results show that the magnitude of the ELZ different along different survey lines and is distinct at different positions along the same survey line. A large ELZ is concluded to surround the two sides of the coal walls and most of the floor. Meanwhile, due to complicated geological structure, local fractured zones exist widely within the ELZ. This case study is quite useful for understanding the range of the ELZ around a soft coal seam with soft rock seams in the coal wall and floor.
•GPR was used to detect the ELZ of soft coal seams with soft roofs and floors.•The picture segmentation method was conducted to optimize the radargrams.•The ELZ extent is not only different at different survey lines, but also distinct at different distances along the same survey lines.
An evaluation system of hydrocarbon-bearing availability of fault traps was established based on the comprehensive analysis of fault segment growth history, fine reservoir anatomy and geochemistry ...tracing, with the Qikou sag in the Bohai Bay Basin as target area. The displacement/separation transform and displacement gradient method were used to prove the interpretation reliability of fault traps. The method of maximum throw subtraction was used to recover the history of fault growth and determine the availability of the forming period of fault traps. Based on the quantitative relationship between shale gouge ratio and cross-fault pressure difference of known reservoirs in southern Qikou sag, the critical shale gouge ratio of fault lateral sealing was calculated at 20%, and the quantitative evaluation chart based on the relationship of “fault throw–sand-formation ratio and hydrocarbon column height” was constructed. Based on the results of reservoir fine anatomy and quantitative fluorescence tracing test shale smear factor method is suitable for evaluating the vertical sealing of faults in the caprock of the middle submember of first member of Paleogene Shahejie Formation, and the shale smear factor critical value is 3.5. The juxtaposition thickness method is suitable for evaluating vertical sealing of faults in the caprock of the second member of Paleogene Dongying Formation, and the critical juxtaposition thickness of fault is 70–80 m. By combining four factors, the availability of fault trap interpretation, the availability of the forming period of fault trap, the availability of fault lateral sealing and the availability of fault vertical sealing, the comprehensive evaluation chart on hydrocarbon-bearing availability of fault traps in Qikou sag has been established, which provides a reasonable basis for risk assessment of fault traps.
The petrophysical property of mudstone often transforms from ductile to brittle in the process of burial-uplift. The deformation mechanism of fault in brittle and ductile mudstone caprock is ...different, which leads to the formation of different types of fault zone structure. Different methods are required to evaluate the sealing mechanism of those fault zones. Based on the caprock deformation mechanism, fault sealing mechanism, quantitative evaluation method of vertical fault sealing capacity is put forward in this study. Clay smear is formed in the process of plastic deformation and its continuity controls the sealing capacity of fault. The outcrop and oil field data have confirmed that when sealing parameter SSF is less than 4–7, the clay smear becomes discontinuous and then oil and gas go through the caprock and migrate vertically. Quantities of fractures are formed in mudstone in the process of brittle deformation. The fracture density increases with the increase of the fault displacement. When the fractures are connected, oil and gas go through the caprock and migrate vertically. The connectivity of fault depends on the displacement and the thickness of caprock. On the basis of the above, a method is put forward to quantify the connectivity of fault with the juxtaposition thickness of caprock after faulting. The research on the juxtaposition thickness of caprock after faulting of the member II of Dongying Formation in Nanpu depression and the distribution of oil and gas indicates when the juxtaposition thickness of caprock is less than 96.2 m, the fault becomes leaking vertically. In the lifting stage, with the releasing and unloading of the stress, the caprock becomes brittle generally and then forms through going fault which will lead to a large quantity of oil and gas migrate vertically.
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