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The oxide scale on the surface of hot‐rolled low‐carbon steel strips is subjected to isothermal reduction in 10 vol%H2–Ar and 20 vol%H2–Ar environments to simulate the reduction process that occurs in a continuous annealing furnace. The influence of hydrogen concentration on the reduction kinetics and the microstructural evolution of the oxide scale after reduction at temperatures ranging from 450 to 850 °C for a duration of 20 min are investigated in detail. The mass changes of the oxide scale in the two gases are quantified using a thermogravimetric analyzer. This data is then employed to calculate the reduction rate constant and the apparent activation energy. To examine the microstructure and element distribution, electron probe microanalysis and energy‐dispersive spectrometry are employed. An novel approach is also undertaken to assess the reduction degree of the oxide scale by measuring surface microhardness. In the findings, it is indicated that an increase in hydrogen concentration served primarily to accelerate the reduction reaction within the temperature ranges of 450–550 and 800–850 °C. Meanwhile, the mechanism of physical transformation of oxide scale, the microstructure of reduction layer, and hydrogen concentration on reduction efficiency under different reaction stages are proposed. [ABSTRACT FROM AUTHOR]

Three new constituents, 4a-hydroxy-1-methyl-4,4a,8,8a-tetrahydro-1 H-isochromene-3,7-dione (1), 1-(2-(prop-1-en-2-yl)-3-((3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2 H-pyran-2-yl)oxy)-2,3-dihydrobenzofuran-5-yl)ethan-1-one (2), and 5-(hydroxymethyl)-2,3-dihydro-1 H-pyrrolizin-1-one (3), together with 3 known flavonoids (4 - 6), 6 organic acids (7 - 12), 1 glycoside (13), and 2 terpenoids (14 - 15) were isolated from the 50 % ethanol extract of the whole plant of Senecio raphanifolius Wall. ex DC. The structures of these novel compounds were determined using high-resolution electrospray ionization–mass spectrometry and NMR, mainly using 2D NMR. The anti-inflammatory activities of compounds 1 - 3 were evaluated based on their ability to inhibit nitric oxide (NO) production in lipopolysaccharide-stimulated RAW264.7 cells. Compound 1 could reduce NO levels and had an inhibition rate of 42.86 % at 100 µM. [Display omitted] ● Novel monoterpene (1), glycoside (2), alkaloid (3) isolated from S. raphanifolius. ● Structures of compounds 1 - 3 were elucidated and determined using NMR and HR-ESI-MS. ● Compound 1 inhibited LPS-stimulated NO production in RAW264.7 cells slightly. [ABSTRACT FROM AUTHOR]

The oxidation behavior of SUS430 ferritic stainless steel is studied during isothermal oxidation at 1100 °C for 2 h under a mixture of 10, 30, and 50% water vapor and air, and oxidation kinetics curves are drawn. The surface morphology and phase composition of oxide scale are analyzed using X‐Ray diffractometer, scanning electron microscope, and energy dispersive spectrometer. The oxidation kinetic curves under three different humidities are S‐shaped and include three stages: induction period, acceleration period, and deceleration period. The controlling steps under 10% water vapor and air are nucleation and growth, while under 30% and 50% water vapor and air are both phase boundary control reactions. The induction period becomes shorter and the breakaway oxidation occurs earlier with increasing water vapor content. The structure of oxide scale produced is layered, with the outer layer being iron oxide and the inner layer being mainly the Fe–Cr spinel phase. The volatilization of Cr and the growth stress of the Cr2O3 layer cause the formation of nodules, and a large number of cracks are generated in oxide scale. The cracks provide diffusion paths, accelerating the diffusion of Fe ions and electrons, as well as the erosion of the substrate. [ABSTRACT FROM AUTHOR]

Objective To reveal the correlation between APACHE III score and sleep quality in patients in the intensive care unit (ICU). Methods This prospective, observational study included patients aged ≥18 years, who had been admitted to an integrated ICU for ≥48 h. Age, sex, Pittsburgh Sleep Quality Index (PSQI) prior to ICU, Numeric Rating Scales (NRS), noise, illumination, number of nursing interventions, Richards Campbell Sleep Questionnaire (RCSQ), and APACHE III score during sleep were evaluated. Results A total of 124 ICU patients were included, all with APACHE III scores

Three new compounds, (8S)-2,2,7,7-tetramethyl-8-hydroxymethyl-6H-indanone-(2,3-b)-2H-pyran-9-O-β-d-glucopyranoside (1), (7S,8S)-2,2,7-trimethyl-7-hydroxymethyl-8-hydroxy-2,7,8,9-tetrahydro-6H-naphtho-(2,3-b)-pyran-10-O-β-d-glucopyranoside (2), 1-deoxy-1-(3,4-dihydro-7-methyl-2,3-dioxo-1(2H)-quinoxalinyl)pentitol-6-carboxylic acid (3), as well as six known compounds (4–9), were obtained. Their structures were determined by spectroscopy and comparison with NMR data of related compounds. Absolute configurations were determined by ECD spectroscopy. The hepatoprotective effects of these compounds were investigated on HepG2 and LO2 cells lines; compounds 1, 2, and 4 displayed moderate activity. [ABSTRACT FROM AUTHOR]

The paper introduced main content, implementation of automatic control and technical difficulties of automation reformation of high-water filling system of coal mine, focused on implementation of automatic control of water-filled test tube, pulp and filling, and water washing pipe, and gave solutions of technical problems of level measurement, flow measurement, and pressure measurement. The reformed system can greatly improve filling quality and save labor costs, which has high promotional value.

In order to improve performances of control system of hydraulic support test-bed, the paper proposed a design scheme of computer control system of lifting platform of hydraulic support test-bed. It detailedly introduced design of hardware and software of each subsystem of the system, namely control subsystem of hydraulic pump station, 4-cylinder synchronization control subsystem of lifting platform and bolt control subsystem, and gave human-computer interaction interface of the system. The actual application showed that the system can finish computer control of lifting platform of hydraulic support test-bed magnificently.