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The current deep convolutional neural network models applied to coal-rock image recognition have problems such as large volume and cumbersome calculation process. It is difficult to meet real-time detection requirements, and it has poor adaptability to complex environments such as low lighting and high dust. In order to solve the above problems, a coal-rock image recognition method integrating drilling geological information is proposed. Firstly, the improved spectral residual saliency detection (ISRSD) algorithm is used to enhance the quality of coal-rock images, effectively reducing the adverse effects of complex environments on the features of coal-rock images. Secondly, the method uses the attentional VGG (AVGG) deep convolutional neural network model. The AVGG performs pruning based on VGG, adds convolutional block attention module (CBAM), and introduces adaptive learning rate adjustment strategy to efficiently extract coal-rock image features. Finally, the Bayesian model is used to integrate the features of coal-rock images with the geological information obtained from the borehole geological column chart, in order to improve the accuracy and robustness of coal-rock classification. The experimental results show that the image enhanced by the ISRSD algorithm has more prominent targets, lower color distortion, and relatively complete preservation of image features such as edges and textures. The accuracy of the AVGG model is comparable to that of the VGG model, but the average inference time, parameter count, and model size are only 15.61%, 33.44%, and 33.40% of the VGG model, respectively. Compared with using only the AVGG model to recognize coal-rock images, using the Bayesian model to fuse drilling geological information improves accuracy by 1.85%, reaching 97.31%.

Proton exchange membrane (PEM) water electrolysis is a green and sustainable method of hydrogen production. The development of efficient and economical electrocatalysts for anodic oxygen evolution reaction (OER) is the key to its large-scale commercialization. Iridium oxide catalysts supported by different manganese based oxide carriers (IrOx/Mn8O10Cl3, IrOx/β-MnO2 and IrOx/α-MnO2) were prepared by two-step synthesis method, and the content of iridium is about 55%. Compared with the commercial IrO2 and other noble metal containing electrocatalysts, the synthesized catalysts have lower overpotential and higher current density. The overpotential of IrOx/β-MnO2 is only 228 mV at the current density of 10 mA/cm2. The specific mass activity of IrOx/Mn8O10Cl3 reaches 916.7 A/gIr at 1.53V. The enhancement of OER activity is attributed to the abundant hydroxyl oxygen defects and IrIII species on the catalyst surface. The rich crystalline-amorphous interface provides a large number of active sites for the reaction. The iridium oxide/manganese based oxide catalysts reported in this paper provide new insights for the development of efficient and economical catalysts for acidic OER.

Carbonate cementation is one of the significant tightness factors in Chang 6 reservoir of the western Jiyuan (WJY) area. Based on the observation of core and thin sections, connecting-well profile analysis as well as carbon and oxygen isotope analysis, it is found that ferrocalcite is the main carbonate cements in the Chang 6 reservoir of the WJY area. The single sand body controls the development of carbonate cements macroscopically. Both carbonate cements and calcite veins hold similar diagenetic conditions: the dissolution of plagioclase is the main calcium source and the de-acidification of organic acids is the main carbon source. The diagenetic stage is identified as the mesogenetic A stage. The sedimentary environment is of low salinity. Accordingly, the development model of carbonate cementation in Chang 6 reservoir is summarized into three types: “eggshell pattern,” “cutting pattern,” and “favorable reservoir pattern.” The development degree of carbonate cementation affects the physical properties of reservoir.

Authigenic chlorite, which is frequently found in sandstone, has a controlling effect on the reservoirs in which tight oil is adsorbed during hydrocarbon filling. In this study, the content, occurrence state, timing, mechanism and influence of authigenic chlorite on the micro-occurrence states of tight oil were studied using Thin Section (TS), Fluorescent Thin Section (FTS), X-Ray Diffraction (XRD), Field Emission-Scanning Electron Microscopy (FE-SEM), Environmental Scanning Electron Microscopy (ESEM), and Energy Dispersive Spectroscopy (EDS). The results indicate: (1) a spatial coupling between chlorite development, a brackish water delta front facies depositional environment, and biotite-rich arkosic sandstone. (2) Authigenic chlorite can be divided into three types: grain-coating chlorite, pore-lining chlorite, and rosette chlorite. Chlorite forms after early compaction but before other diagenetic phases, and grows via precipitation from pore waters that contain products released during the dissolution of volcanic rock fragments and biotites. Porewater is also pressure-released from feldspars and mudstone. (3) The micro-occurrence states of tight oil can be divided into five types: emulsion form, cluster form, throat form, thin-film form, and the isolated or agglomerated particle form. (4) During hydrocarbon filling, tight oil mainly occurs on the surface of grain-coating and pore-lining chlorite in the form of a thin film, the granular or agglomerated forms are mainly enriched within the intercrystalline pores within the authigenic chlorite, and the cluster forms are mainly enriched in dissolution pores. Isolated or agglomerated particles of tight oil primarily occur in the intercrystalline pores of the rosette chlorite. (5) The specific surface area and the authigenic chlorite’s adsorption potential of authigenic chlorite control the micro-occurrence of tight oil on the surface of the chlorite and in intercrystalline pores. The adsorption capacity of chlorite lies in the following order: pore-lining chlorite intercrystalline pores > rosette chlorite > chlorite in feldspar dissolution pores > pore-lining chlorite surface > grain-coating chlorite intercrystalline pores > grain-coating chlorite surface.

Family environment affects children's reading comprehension ability. In poverty-stricken parts of rural China, some parents have been migrant workers for many years. It is common for left-behind children to have one or both parents permanently missing. This study explores the impact of parental absence on children's reading comprehension. We measured the reading comprehension of 903 children (467 left-behind and 436 parented), using the Chinese Primary School Students' Reading Comprehension Ability Scale. After controlling for the parents' levels of education, reading input, and interest variables, we found that children with absent parents had significantly lower reading comprehension scores than parented children; they struggled to understand chapter layout, the author's intentions, writing technique, evaluation, and appreciation. While children with absent fathers received the same scores as parented children, those with absent mothers received significantly lower scores. Clearly, absent mothers have a greater impact on children's reading comprehension than absent fathers.

Abstract In order to determine the activity of O-linked GlcNAc transferase (OGT), a modified coupled enzyme method was proposed. This method was based on the measurement of uridine 5'-(trihydrogen diphosphate) (UDP), a product generated in transglycosylation reaction. In the assay, UDP was coupled to the conversion of phosphoenolpyruvate to pyruvate using pyruvate kinase. Using a commercial pyruvate assay kit, the pyruvate was converted to a red terminal product, which could be photometrically measured at 570 nm or fluorometrically measured at 587 nm (Em = 535 nm) on a microplate reader. Kinetic study of a truncated recombinant mOGT and quantitative analysis of OGT in two biological samples indicated that this method was practical and competitive for quantitative analysis of OGT.

Although emerging evidence suggests that developmental dyslexia shows deficits in visual-spatial attention, previous studies have also confirmed that visual-spatial attention may be particularly important for reading among Chinese children with dyslexia. However, the visual-spatial attention deficit of dyslexic Chinese children has not been fully investigated. Therefore, the present study employed the cue-target paradigm and examined whether the earlier processing of visual-spatial attention deficit would be found in Chinese children with dyslexia. More importantly, we combined read level match design to determine the process of visual-spatial attention in Chinese children with dyslexia related to developmental delay or cognitive deficits. Results showed that developmental dyslexia (DD) group exhibited no cueing effect in the cue-target tasks when the stimulus onset synchronies (SOAs) were set to 100 ms, as compared with the children's chronological age (CA). With the cueing effect as the index, we also observed that the CA group had a robust facilitation effect in early processing of visual-spatial attention. Importantly, the DD group presented an impaired facilitation effect as the same reading level (RL) group controls when SOAs were 100 ms and 350 ms. These findings suggested that impaired facilitation effect in Chinese dyslexic children is due to a developmental delay., Author(s): Baojun Duan [sup.1] , Datao Wang [sup.1] , Wenxue Li [sup.2] , Xiaofeng Ma [sup.3] , Aibao Zhou [sup.3] [sup.4] Author Affiliations: (1) grid.412133.6, 0000 0004 1799 3571, School [...]