27 research outputs found

    Composition of soluble organic matter and its causes of No. 11 coal from Sangshuping Mine, Shaanxi Province

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    Eight samples of No.11 coal in Sangshuping Mine were used for organic geochemical study, Gas chromatography-mass spectrometry (GC-MS) and X-ray fluorescence spectrometry (XRF) were combined with the test results of proximate analysis, sulfur forms and random vitrinite reflectance, the organic matter sources and coal-forming environment of No.11 coal from the Sangshuping mine, Shaanxi Province were comprehensively analyzed. The results indicate that the total sulfur content of the coal sample is 3.29%, and the mean vitrinite oil-leaching reflectance is 2.01%, which is high-sulfur lean coal. The phase parameters of major elements indicate that the coal samples are mainly formed in reductive sedimentary environment. There are two types of carbon number distribution of n-alkanes in saturated hydrocarbon: the front peak type main carbon peak is C16, and the back peak type is main carbon C26; Combined with the distribution characteristics of ∑C22−/∑C23+、(C21+C22)/(C28+C29)、Pr/nC17、Ph/nC18 indicated that the parent material of organic matter come from aquatic organisms and higher plants. The OEP value was between 0.49 to 1.05,with an average value of 0.84, indicating that No.11 coal of Sangshuping has undergone different degrees of biodegradation. In the analysis of saturated hydrocarbon steroidal terpanes, the ratio of w(Ts)/w(Tm) is between 0.83-1.21 and w(Ts)/[w(Ts)+w(Tm)] is between 0.45-0.55, indicating that the thermal evolution degree of coal sample is high. In the analysis of aromatic compounds, the methyl rearrangement of trimethylnaphthalene and the distribution characteristics of methyl phenanthrene index are correlated with the high thermal evolution degree of coal samples. The aromatic hydrocarbons were dominated by naphthalene, phenanthrene and biphenyl series, and the sulfur-containing compounds in the trifluorene series (oxygen-fluorene, sulfur-fluorene, fluorene) are obviously higher than the oxygen-containing compounds, which also indicates the coal-forming environment under higher salinity partial reduction conditions

    NMR-Based Shale Core Imbibition Performance Study

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    Shale gas reservoirs are unconventional resources with great potential to help meet energy demands. Horizontal drilling and hydraulic fracturing have been extensively used for the exploitation of these unconventional resources. According to engineering practice, some shale gas wells with low flowback rate of fracturing fluids may obtain high yield which is different from the case of conventional sandstone reservoirs, and fracturing fluid absorbed into formation by spontaneous imbibition is an important mechanism of gas production. This paper integrates NMR into imbibition experiment to examine the effects of fractures, fluid salinity, and surfactant concentration on imbibition recovery and performance of shale core samples with different pore-throat sizes acquired from the Longmaxi Formation in Luzhou area, the Sichuan Basin. The research shows that the right peak of T2 spectrum increases rapidly during the process of shale imbibition, the left peak increases rapidly at the initial stage and changes gently at the later stage, with the peak of the left peak shifting to the right. The result indicates that water first enters the fracture system quickly, then enters the small pores near the fracture wall due to the effect of the capillary force, and later gradually sucks into the deep and large pores. Both imbibition rate and capacity increase with increased fracture density, decreased solution salinity, and decreased surfactant concentration. After imbibition flowback, shale permeability generally increases by 8.70–17.88 times with the average of 13.83 times. There are also many microcracks occurring on the end face and surface of the core sample after water absorption, which may function as new flowing channels to further improve reservoir properties. This research demonstrates the imbibition characteristics of shale and several relevant affecting factors, providing crucial theory foundations for the development of shale gas reservoirs

    NMR-Based Shale Core Imbibition Performance Study

    No full text
    Shale gas reservoirs are unconventional resources with great potential to help meet energy demands. Horizontal drilling and hydraulic fracturing have been extensively used for the exploitation of these unconventional resources. According to engineering practice, some shale gas wells with low flowback rate of fracturing fluids may obtain high yield which is different from the case of conventional sandstone reservoirs, and fracturing fluid absorbed into formation by spontaneous imbibition is an important mechanism of gas production. This paper integrates NMR into imbibition experiment to examine the effects of fractures, fluid salinity, and surfactant concentration on imbibition recovery and performance of shale core samples with different pore-throat sizes acquired from the Longmaxi Formation in Luzhou area, the Sichuan Basin. The research shows that the right peak of T2 spectrum increases rapidly during the process of shale imbibition, the left peak increases rapidly at the initial stage and changes gently at the later stage, with the peak of the left peak shifting to the right. The result indicates that water first enters the fracture system quickly, then enters the small pores near the fracture wall due to the effect of the capillary force, and later gradually sucks into the deep and large pores. Both imbibition rate and capacity increase with increased fracture density, decreased solution salinity, and decreased surfactant concentration. After imbibition flowback, shale permeability generally increases by 8.70–17.88 times with the average of 13.83 times. There are also many microcracks occurring on the end face and surface of the core sample after water absorption, which may function as new flowing channels to further improve reservoir properties. This research demonstrates the imbibition characteristics of shale and several relevant affecting factors, providing crucial theory foundations for the development of shale gas reservoirs

    Occurrence of harmful elements in the ‘high-aluminium coals’ from the Pingshuo mining district, Shanxi Province, China

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    "High-aluminous coal" is an important coal kind and widely distributed in North China in age of Permo-Carboniferous period. To explore their occurrence state, a total of 15 harmful elements (Li, Ga, In, Cd, Cr, Pb, Be, Mn, Zn, Ag, Co, Ni, Cu, Ba and U) in the No.9 coal and No.11 coal collected from Pingshuo mining district were determined by inductively coupled plasma mass spectrometry (ICP-MS) and scanning electron microscope with energy spectrum (SEM-EDX). The results showed that the content of Li, Ga, In, Pb, Ag and U were all exceed the world hard coal. In view of the result of clustering analysis within trace elements, it was found that Co, Ni, Zn, Cu, Ag and Cr were mainly associated with sulfide minerals due to their common sulfophilic property. Manganese was mainly occurred in carbonate minerals, while Ba, Cd and U were mainly associated with total minerals. In addition, Pb was related to sulfides and Be is mainly distributed in clay minerals. The enrichment of such harmful elements in Pingshuo coal was caused by the combined effect of transgression and input of terrestrial materials in the peat accumulation stage. Li, Ga, In and Ag have reached the harmful grade

    <em>Astragalus </em><em>m</em><em>embranaceus</em> Extract Activates Immune Response in Macrophages via Heparanase

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    <em>Astragalus membranaceus</em> (AM), a traditional Chinese medicinal herb, has immunoregulatory properties in many diseases. We investigated the effects and mechanism of <em>Astragalus membranaceus</em> extract (AME) in the macrophage migration and immune response mediator release. The viability of Ana-1 macrophages treated with AME was evaluated by the MTT method. The secretion and mRNA levels of IL-1β and TNF-a were measured by ELISA and RT-PCR, respectively. Macrophage migration was assayed by transwell assay. The activity of heparanase (HPA) was determined by a heparin-degrading enzyme assay. Our results didn’t show any toxicity of AME in macrophages. AME increased the activity of HPA, cell migration, mRNA levels and secretion of IL-1β and TNF-a in macrophages. Pretreatment with anti-HPA antibody reduced cell migration, secretion of IL-1β and TNF-a did not change the mRNA levels of IL-1β and TNF-a significantly in AME-treated macrophages. This suggests that AME may increase the release of immune response mediator and cell migration via HPA to activate immune response in macrophages

    Unveil the transcriptional landscape at the Cryptococcus-host axis in mice and nonhuman primates.

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    Pathogens and hosts require rapid modulation of virulence and defense mechanisms at the infection axis, but monitoring such modulations is challenging. In studying the human fungal pathogen Cryptococcus neoformans, mouse and rabbit infection models are often employed to shed light on the disease mechanisms but that may not be clinically relevant. In this study, we developed an animal infection model using the non-human primate cynomolgus monkey Macaca fascicularis. In addition, we systematically profiled and compared transcriptional responses between the infected mice and the cynomolgus monkey, using simultaneous or dual RNA next-generation sequencing. We demonstrated that there are shared but distinct transcriptional profiles between the two models following C. neoformans infection. Specifically, genes involved in immune and inflammatory responses are all upregulated. Osteoclastogenesis and insulin signaling are also significantly co-regulated in both models and disrupting an osteoclastogenesis-associated gene (OC-STAMP) or the insulin-signaling process significantly altered the host tolerance to C. neoformans. Moreover, C. neoformans was shown to activate metal sequestration, dampen the sugar metabolism, and control cell morphology during infection. Taking together, we described the development of a non-human primate model of cryptococcosis that allowed us to perform an in-depth analysis and comparison of transcriptome profiles during infections of two animal models and conceptually identify host genes important in disease responses. This study provides new insights in understanding fungal pathogenesis mechanisms that potentially facilitate the identification of novel drug targets for the treatment of cryptococcal infection

    Effects of Cd<sup>2+</sup> on Cx43 expression in Cx43-LLC-PK1 cells.

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    <p>(A–C) Time- and dose-dependent effects of Cd<sup>2+</sup> on Cx43 protein levels. Cx43-LLC-PK1 cells were treated with 35 μM CdCl<sub>2</sub> for the indicated duration (A) or exposed to the indicated concentrations of CdCl<sub>2</sub> for 6 h (C). The cellular protein was extracted and subjected to Western blot analysis of Cx43. In Western blot (A), Cx43 was detected at the molecular near 70 kDa (upper band) and 43 kDa, representing EGFP-tagged and untagged Cx43, respectively. P0, P1 and P2 denoted the nonphophorylated, phosphorylated and hyper-phosphorylated Cx43. (B) Densitometric analysis of Cx43 expression shown in A. Results were expressed as induction relative to the basal level of Cx43 (mean ± S.D., n = 3). # <i>p</i><0.01 versus untreated control. (D) Effect of Cd<sup>2+</sup> on Cx43 mRNA expression. Cx43-LLC-PK1 cells were exposed to 35 μM CdCl<sub>2</sub> for the indicated duration. Cellular RNA was extracted and subjected to Northen blot analysis of Cx43. The level of GAPDH was shown as a loading control. (E) Effect of Cd<sup>2+</sup> on Cx43-EGFP distribution. LLC-PK1 cells permanently transfected with a vector encoding Cx43-EGFP were exposed to 35 μM CdCl<sub>2</sub>. The expression and localization of Cx43-EGFP at different time points following Cd<sup>2+</sup> stimulation were shown. Note the obviously increased expression of Cx43-EGFP and shift of fusion protein from cell membrane (arrow head) to perinuclear region (white arrow) after incubation with Cd<sup>2+</sup>.</p
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