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Bias flow of molten metal in slab mold caused by unstable flow from submerged entry nozzle can deteriorate the slab quality during continuous casting. In this study, a novel electromagnetic swirling flow in nozzle (EMSFN) technique, which utilizes electromagnetic force to stabilize the flow in the nozzle and subsequently control the flow in the mold, is proposed. The mechanism for controlling unstable flow through EMSFN is explored through numerical simulation and water model experiments. In the results, it is shown that the molten steel is rotated under the effect of magnetic field and flows into the mold along the upper edge of the nozzle outlet, which weakens the impact of molten steel on the bottom of nozzle and stabilizes the outflow from nozzle. The flow field is consistently symmetrical on both sides of the nozzle. The impact depth of molten steel flowing down along the narrow sides of the mold on both sides is greatly reduced. The surface velocity on both sides of the nozzle changes uniformly. The range of surface velocity variation with EMSFN is only 10% of that with a conventional nozzle. The EMSFN technique can help prevent slag entrapment and improve the flotation of inclusions and bubbles. [ABSTRACT FROM AUTHOR]

Vortex slag entrapment during ladle teeming process causes liquid steel pollution, nozzle clogging, etc. Tangential velocity of molten steel is directly related to the vortex. Herein, the tangential velocity is reduced by the electromagnetic force generated by the interaction between a static electromagnetic field and the molten steel. Through the multiphysical field simulation, influences of the electromagnetic parameter, coil structure, coil position, and ladle structure on the vortex are investigated. Results demonstrate that magnetic induction intensity is proportional to the coil ampere‐turns, thereby affecting the vortex suppression. The action region of the static electromagnetic field expands when the coil diameter increases from 180 to 360 mm; it is beneficial to reduce the vortex critical height by 37.9%. The reduction of the distance between the coil and the molten steel also promotes the vortex suppression. The coil misalignment is beneficial to fully utilize the electromagnetic field; the critical height is reduced by 15%. The tangential velocity is changed when the nozzle diameter and eccentricity are optimized, and the vortex suppression will be amplified by using the electromagnetic field. This study provides the theoretical guidance for the optimizing design of the vortex suppression utilizing the static electromagnetic field. [ABSTRACT FROM AUTHOR]

In this work, the two example rare earth‐based metal‐organic frameworks (LaIII‐based MOFs), Eu‐ETTB and Gd‐ETTB, were obtained by self‐assembly. Both materials showed extremely high proton conductivity, with the proton conductivity of Eu‐ETTB being 1.53×10−2 S cm−1 at 98 % relative humidity (RH) and 85 °C and that of Gd‐ETTB being 2.63×10−2 S cm−1 at 98 % RH and 75 °C. This was almost the best performance observed for three‐dimensional porous MOFs without post‐synthetic modification and was based on milder conditions than for most materials. Furthermore, cycle test experiments and continuous work tests showed that both materials had excellent performance both in terms of stability and durability. Water vapor adsorption experiments showed that a large number of water molecules are adsorbed the hydrogen‐bond network's being rebuilt by the adsorbed water molecules in the pore channel and thus optimizing the channels for proton transfer explained the MOF's high performance. [ABSTRACT FROM AUTHOR]

Testosterone is produced by Leydig cells (LCs) and undergoes diurnal changes in serum levels in rats, mice, and humans, but little is known in goats. The present study revealed that goat serum testosterone levels displayed diurnal rhythmic changes (peak time at ZT11.2). Immunohistochemical staining showed that BMAL1, a circadian clock protein, is highly expressed in goat LCs. ELISA revealed that both hCG (0–5 IU/ml) and 22R‐OH‐cholesterol (0–30 μM) addition stimulated testosterone synthesis in primary goat LCs in a dose‐dependent manner. Treating goat LCs with hCG (5 IU/ml) significantly increased intracellular cAMP levels. Additionally, real‐time quantitative polymerase chain reaction (PCR) analysis revealed that the circadian clock (BMAL1, PER1, PER2, DBP, and NR1D1) and steroidogenesis‐related genes (SF1, NUR77, StAR, HSD3B2, CYP17A1, CYP11A1, and HSD17B3) showed rhythmic expression patterns in goat LCs following dexamethasone synchronization. Several Bmal1‐Luc circadian oscillations were clearly observed in dexamethasone‐treated goat LCs transfected with the pLV6‐Bmal1‐Luc plasmid. BMAL1 knockdown significantly downregulated mRNA levels of PER2, NR1D1, DBP, StAR, HSD3B2, SF1, NUR77, and GATA4, and dramatically decreased StAR and HSD3B2 protein levels and testosterone production. In contrast, BMAL1 overexpression significantly increased the mRNA and protein expression levels of StAR and HSD17B3 and enhanced testosterone production. Reporter assays revealed that goat BMAL1, or in combination with mouse CLOCK, activated goat HSD17B3 transcription in vitro. These data indicate that BMAL1 contributes to testosterone production by regulating transcription of steroidogenesis‐related genes in goat LCs, providing a basis for further exploring the underlying mechanism by which the circadian clock regulates ruminant reproductive capability. [ABSTRACT FROM AUTHOR]

Ultrafine grained (UFG) steels with grain sizes around 1 micron exhibit an excellent strength‐ductility combination and have been extensively studied worldwide. Among the different grain refinement strategies, thermomechanical controlled processing (TMCP) employing dynamic transformation (DT), that is, ferrite transformation during deformation of austenite, is considered as the simplest and commercially exploitable approach to produce ultrafine ferrite (UFF) with grain size of a couple of microns or below. The present paper reviews the research history of DT and highlights the major aspects of continuous interest including the methods and evidences for identifying DT, thermodynamics and kinetics of DT, mechanism for UFF formation and the effects of some key thermomechanical parameters on DT (and UFF formation), together with an outlook for the future research, and new TMCP design for industrial application. This paper also discusses some areas remaining under debate such as the diffusional or displacive mechanism, thermodynamic modeling, and the mechanism for UFF formation, etc. [ABSTRACT FROM AUTHOR]

The grain refinement mechanism of ferrite dynamically transformed (DT) from austenite is investigated in a 10Ni-0.1C steel. For decades, it has been debated whether dynamic recrystallization (DRX) contributes to the grain refinement of DT ferrite. Here, the authors show that the role of DRX has been previously underestimated in grain refinement of ferrite and intrinsically it is the DRX that leads to ultra grain refinement of DT ferrite. The DT ferrite shows an unconventional grain growth behavior, that is, grain coarsening at an early stage of transformation with subsequent grain refinement by DRX, which strongly depends on the strain rate. The high strain concentration on fine ferrite grains within the austenite + ferrite structure produced by DT mainly contributes to the occurrence of DRX to form ultrafine-grained ferrite structures. [ABSTRACT FROM AUTHOR]

Cellular oscillators in the uterus play critical roles in the gestation processes of mammals through entraining of the clock proteins to numerous downstream genes, including growth/differentiation factor ( Gdf) 10 and Gdf15. The expression of Gdf10 and Gdf15 is significantly increased in the uterus during decidualization, but the mechanism underlying the regulation of Gdf gene expression in the uterus is poorly understood. Here, we focused on the function of the cellular oscillators in the expression of Gdf family by using uterine endometrial stromal cells ( UESCs) isolated from pregnant Per2- dLuc transgenic rats. A significant decline of Per2- dLuc bioluminescence activity was induced in in vitro decidualized UESCs, and concomitantly the expression of canonical clock genes was downregulated. Conversely, the expression of Gdf10 and Gdf15 of the Gdf was upregulated. In UESCs transfected with Bmal1-specific si RNA, in which Rev-erbα expression was downregulated, Gdf10 and Gdf15 were upregulated. However, Gdf5, Gdf7, and Gdf11 were not significantly affected by Bmal1 silencing. The expression of Gdf10 and Gdf15 was enhanced after treatment with a REV- ERB α antagonist in the presence or absence of progesterone. Chromatin immunoprecipitation- PCR analysis revealed the inhibitory effect of REV- ERB α on the expression of Gdf10 and Gdf15 in UESCs by recognizing their gene promoters. Collectively, our findings indicate that the attenuation of REV- ERB α leads to an upregulation of Gdf10 and Gdf15 in decidual cells, in which cellular oscillators are impaired. Our results provide novel evidence regarding the functions of cellular oscillators regulating the expression of downstream genes during the differentiation of UESCs. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks, porous materials, proton conduction, rare earth, tetraphenylethylene Front Cover: Two Novel Three-Dimensional Tetraphenylethylene-Based Rare Earth MOFs with Ultra-High Proton Conductivity and Performance Stability (Chem. Eur. J. 60/2022) Keywords: metal-organic frameworks; porous materials; proton conduction; rare earth; tetraphenylethylene EN metal-organic frameworks porous materials proton conduction rare earth tetraphenylethylene 1 1 1 10/28/22 20221026 NES 221026 B Eu-ETTB and Gd-ETTB were obtained by self-assembly b ; their three-dimensional frameworks provide a channel for proton conduction. [Extracted from the article]

To enhance adsorption of organic dyes like malachite green (MG) onto polymeric absorbents, we prepared carbon nanotube (CNT) filled polyaniline (PANI) composites with large surface areas by simply using entangled CNTs as porous frameworks during PANI polymerization. Adsorption behavior of the CNT/PANI composites in MG solutions was experimentally investigated and theoretically analyzed. The CNT/PANI composites exhibit much higher equilibrium adsorption capacity of 13.95 mg g−1 at an initial MG concentration of 16 mg L−1, increasing by 15% than the neat PANI, which is mainly attributed to large surface areas and strong CNT-PANI interactions of the composites. In addition, theoretical analyses indicate that the adsorption kinetics and the isothermal process of the composites can be well explained by using the Ho pseudosecond-order model and the Langmuir model, respectively. In light of their high MG adsorption and easy operation, the CNT/PANI composites have great potential as high-efficiency adsorbents for removal of dyes from wastewater. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]