13 research outputs found

    Analytical Calculation of Coupled Magnetothermal Problem in Gas Insulated Transmission Lines

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    Gas insulated transmission lines (GIL) are a new technology for transmitting power over long distances. In this paper, an analytical method (AM) is proposed to investigate the coupled magnetothermal problem in GIL. Kelvin functions are employed to calculate the skin effect coefficients of the conductor and the enclosure. The calculated power losses are used as heat source input for the thermal analysis. Considering the convective and radiation heat transfer effects, the heat balance equations on the surface of the conductor and the enclosure are established, respectively. Temperature rise of the GIL at different operation conditions are investigated. The proposed method is validated against the finite element method (FEM). The simplicity of the approach makes it attractive for self-made software implementation in the thermal design and the condition monitoring of GIL

    Upgrading Ethanol to <i>n</i>‑Butanol in the Presence of Carbonate Catalyzed by a Cp*Ir Complex Bearing a Functional 2,2′-Carbonylbibenzimidazole Ligand

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    Upgrading ethanol to n-butanol as biofuels is an important topic for sustainable chemistry. Herein, a Cp*Ir complex bearing a functional 2,2′-carbonylbibenzimidazole ligand [Cp*Ir(2,2′-COBiBzImH2)Cl][Cl] was designed and synthesized. In the presence of a catalyst (0.1 mol %) and Cs2CO3 (6 mol %), the highest yield of updated n-butanol is up to 37% with 80% selectivity. NH units in the ligand are crucially important for the catalytic activity of the iridium complex

    Logging identification of high-quality shale of the marine-continent transitional facies: An example of the Shan 2 Member of the Daning-Jixian area in the Ordos Basin

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    On the southeastern margin of the Ordos Basin, the mineral composition of marine-continent transitional facies deposits is complex. The shale, sandstone, coal, and related lithofacies frequently interact, and the lithology changes rapidly in the vertical direction. Due to the low resolution of conventional logging method and borehole enlargement which is a common while drilling, the commonly used methods for identification of lithology including high-quality shale which is prevailing in marine shale gas evaluation are less effective for the study area. First, deconvolution technology was used to improve the resolution of natural gamma rays, gamma rays without uranium and uranium logging curves. Then, a log cross-plot was used to identify the lithology including shale of marine-continent transitional facies, and the uranium-spontaneous potential curve overlap method was proposed to identify high-quality shale from marine-continent transitional facies. The results show that the deconvolution method can effectively improve the vertical resolution of natural gamma rays, gamma rays without uranium and uranium logging curves. The cross-plot of natural gamma-density logging data has a better effect on identifying the lithology of the marine-continent transitional facies, and the cross-plot of uranium logging data and gamma ray data without uranium can further identify three types of shale lithofacies (calcareous siliceous shale, siliceous clay shale and clay shale). In the marine-continent transitional facies, the newly proposed uranium-spontanous potential overlap method is better than the traditional ΔlogR method inidentifying high-quality shale. This research can provide theoretical support for reservoir evaluation of marine-continent transitional shale gas and improve the accuracy of high-quality shale identification

    Metal-ligand cooperative iridium complex catalyzed C-alkylation of oxindole and 1,3-dimethylbarbituric acid using alcohols

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    A general and high-efficiency C-alkylation of oxindoles and barbituric acids has been developed by a Cp∗Ir complex [Cp∗Ir (2,2′-bpyO)(OH)]Na with a bipyridine-based functional ligand. In particular, H2O was selected as the solvent instead of the organic solvent in this catalytic system. Through mild reaction conditions gave a variety of corresponding alkylated heterocyclic compounds with good to excellent yields. More importantly, the gram-scale C-alkylation reaction was successfully carried out with good yield using a common route with only a single purification by column chromatography

    Recently duplicated sesterterpene (C25) gene clusters in Arabidopsis thaliana modulate root microbiota

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    Land plants co-speciate with a diversity of continually expanding plant specialized metabolites (PSMs) and root microbial communities (microbiota). Homeostatic interactions between plants and root microbiota are essential for plant survival in natural environments. A growing appreciation of microbiota for plant health is fuelling rapid advances in genetic mechanisms of controlling microbiota by host plants. PSMs have long been proposed to mediate plant and single microbe interactions. However, the effects of PSMs, especially those evolutionarily new PSMs, on root microbiota at community level remain to be elucidated. Here, we discovered sesterterpenes in Arabidopsis thaliana, produced by recently duplicated prenyltransferase-terpene synthase (PT-TPS) gene clusters, with neo-functionalization. A single-residue substitution played a critical role in the acquisition of sesterterpene synthase (sesterTPS) activity in Brassicaceae plants. Moreover, we found that the absence of two root-specific sesterterpenoids, with similar chemical structure, significantly affected root microbiota assembly in similar patterns. Our results not only demonstrate the sensitivity of plant microbiota to PSMs but also establish a complete framework of host plants to control root microbiota composition through evolutionarily dynamic PSMs

    Molecular signatures of major depression

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    Adversity, particularly in early life, can cause illness. Clues to the responsible mechanisms may lie with the discovery of molecular signatures of stress, some of which include alterations to an individual's somatic genome. Here, using genome sequences from 11,670 women, we observed a highly significant association between a stress-related disease, major depression, and the amount of mtDNA (p = 9.00 x 10(-42), odds ratio 1.33 [95% confidence interval [CI] = 1.29-1.37]) and telomere length (p = 2.84 x 10(-14), odds ratio 0.85 [95% CI = 0.81-0.89]). While both telomere length and mtDNA amount were associated with adverse life events, conditional regression analyses showed the molecular changes were contingent on the depressed state. We tested this hypothesis with experiments in mice, demonstrating that stress causes both molecular changes, which are partly reversible and can be elicited by the administration of corticosterone. Together, these results demonstrate that changes in the amount of mtDNA and telomere length are consequences of stress and entering a depressed state. These findings identify increased amounts of mtDNA as a molecular marker of MD and have important implications for understanding how stress causes the disease
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