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[Display omitted] • The temperature-dependent stick–slip behavior and its association with interfacial interaction were revealed. • Reduced stick–slip intensity resulted from the interfacial interaction shifting from adhesion to plastic deformation. • The digital image correlation method was employed to analyze the deformation displacement of friction pairs quantitatively. The stick–slip behavior of polymer/metal is a complex frictional issue since the properties of polymers are highly temperature-sensitive. The present study aimed to shed light on the key factors influencing the stick–slip behavior of polyamide-66/zinc-coated steel by conducting experiments at varying temperatures. The results revealed that the stick–slip behavior and interfacial interaction are temperature-dependent. The friction behavior transitioned from stick-slip to smooth sliding at 40 °C. The transition in the interfacial interaction from adhesion to plastic deformation with increased temperature was responsible for the reduction in stick–slip intensity. The reductions in both the potential energy and static friction force were believed to cause the decreased stick–slip intensity, as evidenced by the in-situ observation of the friction pairs through the digital image correlation (DIC) method. The present study could provide a comprehensive and targeted approach to suppressing the stick–slip behavior of polymer/metal over a wide range of temperatures. [ABSTRACT FROM AUTHOR]

By employing the multifunctional organic ligand, 2-(o-bromo)phenyl-4,5-imidazole dicarboxylic acid (o-H 3 BrPhIDC), two three-dimensional supramolecular complexes, [M(o-H 2 BrPhIDC) 2 (H 2 O) 2 ]·CH 3 CH 2 OH·3H 2 O (M = Zn ( 1 ); Co ( 2 )) have been successfully solvothermally synthesized, and structurally characterized by single crystal X-ray crystallography. Their proton conduction properties have been explored under different temperature and relative humidity (RH). Compounds 1 and 2 indicate high conductivity values of 1.14 × 10 −4  S·cm −1 and 3.11 × 10 −4  S·cm −1 , respectively, at 98% RH and 100 °C. The hydrogen bonding nets inside the two complexes perform a vital function in the resultant conductivity. Variable-temperature and Variable-RH experiments of both compounds reveal that the conductivity values increase with increasing temperature and RH. The proton transfer mechanisms of the complexes have been proposed in terms of the structural analyses, activation energy calculations and PXRD determinations. [ABSTRACT FROM AUTHOR]

Three metal–organic frameworks, [Ba( o -CPhH 2 IDC)] n ( 1 ), {[Ca( o -CPhH 2 IDC)(H 2 O) 2 ]·H 2 O} n ( 2 ), ( o -CPhH 4 IDC = 2-(2-carboxylphenyl)-1 H -imidazole-4,5-dicarboxylic acid) and {[Cd( m -CPhH 2 IDC)(phen)]·H 2 O} n ( 3 ) ( m -CPhH 4 IDC = 2-(3-carboxylphenyl)-1 H -imidazole-4,5-dicarboxylic acid and phen = 1,10-phenanthroline), have been solvothermally synthesized and structurally characterized by elemental analyses, IR, thermogravimetric analyses and single-crystal X-ray diffraction. Compound 1 is a (5,5)-connected 3D structure. Compound 2 displays an infinite 1D double-chain structure. Complex 3 presents a wave-like architecture by π–π interactions from neighboring zig zag chains. The imidazole-based multi-carboxylate ligand demonstrates a strong coordination ability and versatile coordination modes. Furthermore, the thermal and solid-state photoluminescent properties have also been investigated. [ABSTRACT FROM AUTHOR]

The circadian clock system plays an important role in regulating testosterone synthesis in mammals. Male Bmal1 −/− mice are infertile with low serum testosterone levels and decreased expression of testicular steroidogenic genes, suggesting that circadian clock genes regulate testosterone biosynthesis by activating steroidogenic gene transcription. However, whether the circadian clock regulates testosterone production via other genes remains unknown. Using Bmal1 −/− mice and their wild-type (WT) siblings, we aimed to identify additional genes by which the circadian clock regulates testosterone synthesis. WT and Bmal1 −/− mouse testes sections had similar normal morphologies, although there was a decrease in testicular spermatozoa in the Bmal1 −/− mice. Low serum testosterone levels were detected in the Bmal1 −/− mice. RNA sequencing identified 37 and 48 genes that were differentially expressed between WT and Bmal1 −/− mouse testes at circadian time (CT2 and CT14), respectively. The cholesterol metabolism pathway was significantly enriched in the KEGG pathway analysis, and there was lower expression of three apolipoprotein genes (Apoa1 , Apoa2 , and Apoc3) at CT2 in the testes of Bmal1 −/− mice than in those of WT mice. These decreases in Apoa1 , Apoa2 , and Apoc3 expression were verified by quantitative polymerase chain reaction analysis, which also revealed downregulation of the expression of the circadian clock (Per2 , Dbp , and Nr1d1) and steroidogenic (StAR , Cyp11a1 , and Hsd17b3) genes. The expression of circadian clock genes was relatively stable in WT mice over a 20-h period, whereas there was clear circadian rhythmic expression of Apoa1 , Apoa2 , Apoc3 , StAR , Cyp11a1 , Hsd3b2 , and Hsd17b3. Bmal1 −/− mice showed severely reduced expression of testicular circadian clock genes at three time points (CT4, CT12, and CT20), and a reduction in mRNA expression levels of Apo (Apoa1 , Apoa2 , and Apoc3) and steroidogenic (StAR , Cyp11a1 , Hsd3b2 , and Hsd17b3) genes. Oil Red O staining showed decreased lipid aggregation in the Leydig cells of Bmal1 −/− mouse testes. Considering the vital role of Apo genes in high-density lipoprotein formation and cholesterol transport, the present data suggest that the circadian clock system regulates testosterone production by orchestrating the rhythmic expression of Apo genes. These data extend our understanding of the role of the circadian clock in regulating testosterone production in mammals. • Robust rhythmic expression of apolipoprotein genes was detected in WT mice testes. • The rhythmic expression of apolipoprotein genes was lost in Bmal1 −/− mice testes. • Reduced expression of apolipoprotein genes was observed in Bmal1 −/− mice testes. • The cholesterol metabolism pathway is severely impaired in Bmal1 −/− mice testes. • Lipid accumulation in Bmal1 −/− mice Leydig cells was clearly attenuated. [ABSTRACT FROM AUTHOR]

• Mg-doped and ZnMgo-coated shell of ZnO NPs were synthesized using the sol-gel method. • The performance of QLED devices using Mg-doped ZnO NPs as ETLs was significantly improved, achieving a maximum EQE of 6.0 % and a maximum current efficiency of 8.2 cd A−1. • The device performance was further improved by utilizing Mg-doped and ZnMgO-coated ZnO NPs as ETL, which achieved a maximum EQE of 9.0 % and a maximum current efficiency of 11.5 cd A−1. ZnO nanoparticles (NPs) are considered the most promising materials for electron transport layer (ETL) in quantum dot light-emitting diodes (QLEDs). Herein, we employed a synergistic strategy of Mg doping and ZnMgO shell coating to modify the defect states and energy levels of ZnO NPs. Mg doping mitigated the exciton luminescence quenching caused by charge transfer. A ZnMgO shell was also applied to coat the Mg-doped ZnO (ZMO) NPs to passivate surface oxygen defects further. Consequently, QLEDs utilizing ZMO@ZnMgO ETL demonstrate external quantum efficiency and maximum current efficiency of 9.0 % and 11.5 cd A−1. This work shows an effective defect passivation strategy to enhance the performance of red-emitting InP-based QLEDs. A coordinated strategy of Mg doping and ZnMgO shell coating was employed to modify the defect states and energy levels of ZnO nanoparticles to improve the performance of red-emitting InP-based QLEDs. With Mg doping, the conduction band minimum of ZnO NPs shifts upward, which reduces the electron accumulation at the QD/ZnO interface and mitigates exciton luminescence quenching caused by spontaneous charge transfer at the interface. Additionally, a ZnMgO shell was applied to coat the Mg-doped ZnO (ZMO) NPs to passivate surface oxygen defects and improve the luminescence efficiency of the QLED devices. As a result, QLEDs utilizing ZMO@ZnMgO ETLs demonstrate an external quantum efficiency of 9.0 % and a maximum current efficiency of 11.5 cd A−1, which are approximately 2.4-fold higher than those of the devices with ZnO ETLs. [Display omitted] [ABSTRACT FROM AUTHOR]

In this preliminary work, a series of LaCr x Mn 1-x O 3 (x = 0, 0.25, 0.5, 0.75, 1) ceramic powders were initially synthesized by a facile solid-state reaction method. In the next step, high emissivity coatings were successfully papered by air-spraying using LaMnO 3 powder as the filler material (with the highest emissivity ε 3–5μm, 600 °C = 0.922) and phosphate as the binder phase. The morphology, structure, and infra-red emissivity of the samples were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and infra-red emissometery. High-temperature cyclic heat treatment results showed that the prepared coating has very good adhesion and excellent high-temperature resistance. A simulated furnace heating test revealed that the prepared coating can save input energy as high as 13.2%. The coating exhibited excellent energy saving performance. [Display omitted] • LaCr x Mn 1-x O 3 ceramic powders were successfully prepared by solid-state reaction. • Effect of B-site doping on the IR emissivity of the prepared powders was studied. • High emissivity coatings were papered using LaMnO 3 powder and phosphate binder. • Prepared coating with high emissivity ε 3–5 μm = 0.93 and ε 8–14 μm = 0.94 at 600 °C. • Prepared coatings showed good adhesion and excellent high-temperature resistance. [ABSTRACT FROM AUTHOR]

The circadian system performs an important role in mammalian reproduction with significant effects on hormone secretion. Nuclear receptor subfamily 1 group D member 1 (NR1D1) functions as a transcriptional repressor in the circadian system and affects granulosa cells (GCs), but how it regulates estrogen synthesis has not been clarified. We investigated the effect of NR1D1 on estrogen synthesis and found that NR1D1 was highly expressed in GCs, mainly in cell nuclei. Additionally, the expression of NR1D1 and estrogen synthesis key genes CYP19A1 , CYP11A1 and StAR showed rhythmic changes in porcine ovarian GCs. Activation of NR1D1 enhances its ability to inhibit the transcriptional activity of CYP19A1 by binding to the RORE on the CYP19A1 promoter, resulting in a decrease in estradiol content. Interference with NR1D1 can eliminate the transcriptional inhibition of CYP19A1 and promote the synthesis of estradiol. The results suggest that the hormone secretion of the ovary itself is also regulated by the biological clock, and any factors that affect the circadian rhythm can affect the endocrine and reproductive performance of sows, so the natural rhythm of sows should be maintained in production. • NR1D1 was highly expressed in granulosa cells, mainly in cell nuclei. • NR1D1 inhibits the synthesis of estradiol in granulosa cells. • NR1D1 regulates estrogen synthesis through affecting the transcription of CYP19A1. [ABSTRACT FROM AUTHOR]

In this article, a unique high infrared emissivity porous ceramic coating was prepared by slurry spraying method. In the first step, flower-like CeO 2 powder particles were synthesized by precursor pyrolysis method using Ce 2 (CO 3) 3 ·8H 2 O as the transition phase. Subsequently, flower-like CeO 2 ceramic particles (filler) and silicate (binder) were deposited by air spraying. The microstructure and phase composition of the prepared particles and the ceramic coating were examined using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and X-ray diffraction (XRD). High temperature performance of the coating was assessed by conducting prolong isothermal oxidation and thermal shock tests. Infrared emissivity of the coating was tested at 750 °C by employing infrared radiation instrument. The prepared coating exhibited excellent high temperature resistance and high infrared emissivity (ε 3-5μm = 0.887, ε 8-14μm = 0.889 and ε 2.5-19μm = 0.893) at 750 °C. This was attributed to the presence of a large number of pores (within and among CeO 2 particles) in the coating. In the end, possible mechanisms related with high infrared emissivity of the coating were discussed in detail. [Display omitted] • Unique flower-like CeO 2 particles were synthesized by precursor pyrolysis method. • Ceramic coating was prepared by air spraying using silicate and CeO 2 particles. • Prepared coating contains large number of pores due to unique structure of CeO 2. • Coating resulted in high infrared emissivity due to multiple reflections at pores. [ABSTRACT FROM AUTHOR]

Abstract Nowadays, a new concept of process utilizing dynamic ferrite transformation, which can achieve ultrafine-grained structure with a mean grain size of approximately 1 μm, has been proposed. This paper reports transformation mode of dynamic ferrite transformation and formation mechanism of ultrafine-grained structure revealed by our novel technique of in-situ neutron diffraction analysis during thermomechanical processing. Dynamic ferrite transformation occurs in a diffusional manner, whose partitioning behavior changes from para- to ortho-equilibrium with the progress of transformation. Moreover, we propose that dynamic recrystallization of dynamically-transformed ferrite is the main mechanism for the formation of ultrafine-grained structure. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

[Display omitted] • CFs, nano Fe 2 O 3 and dispersant were incorporated in the cement composites. • The maximum Seebeck coefficient of the cement composite is 1.1234 mV ∙ K - 1 . • The highest ZT is 8.51 × 10−5 even with very low addition of CFs and Fe 2 O 3 at 85 °C. • The composites have potential application in energy harvesting in infrastructures. Cement based thermoelectric materials have attracted great interest due to their fascinating prospects for harvesting, storing and further converting the absorbed ambient energy into electrical energy. In this paper, nano Fe 2 O 3 /carbon fiber (CF)/cement-based composites were fabricated by introduced nano Fe 2 O 3 , CFs and polyoxyethylene nonyl phenyl ether (TX10) into cement matrix. The thermoelectric and the mechanical properties, and the surface structures were investigated as well. The results show TX10 promoted dispersion for both of CF and nano Fe 2 O 3 particles in the cement. The nano Fe 2 O 3 /CF/cement-based composites incorporated with 0.6 (wt.) % TX10 revealed not only better thermoelectric effects, but also denser structure, higher mechanical strengths and smaller surface area than the composites with other adding levels of TX10. We report the maximum Seebeck coefficient of 1.1234 mV ∙ K - 1 and the highest thermoelectric figure of merit (ZT) of 8.51 × 10−5 (85 °C) in this work. The enhanced thermoelectric properties of the nano Fe 2 O 3 /CF/cement-based composites are appealing for potential application in energy harvesting and storing, and thus alleviating the urban heat island (UHI) effect. [ABSTRACT FROM AUTHOR]

The circadian clock and autophagy are essential biological mechanisms involved in regulating many physiological processes. Accumulating evidence has revealed that autophagic activity is regulated by the circadian clock system. However, whether autophagy regulates the circadian clock system remains unclear. In this study, rapamycin and AICAR, two classical activators of autophagy, were used to create autophagy activation models in BMAL1-dLuc U2OS cell line. The results showed that the mRNA expression of MAP1LC3B and ATG5 were significantly upregulated after autophagy activation, whereas the mRNA expression of circadian clock genes (BMAL1 , PER2 , REV-ERBα , and DBP) were significantly decreased. Consistent with these data, the relative ratio of LC3-II/LC3-I and the protein level of ATG5 were increased after rapamycin or AICAR treatment. In contrast, BMAL1 and REV-ERBα levels were decreased. Notably, the mRNA expression of circadian clock genes (BMAL1 , PER2 , REV-ERBα , and DBP) and autophagy-related genes (MAP1LC3B and ATG5) showed rhythmic expression patterns in both untreated and rapamycin/AICAR-treated U2OS cells. Moreover, the autophagy inhibitor 3-methyladenine partially reversed the inhibitory effects of autophagy on circadian clock genes expression and BMAL1-Luc oscillations. Another critical finding was that ATG5 knockout alleviates the inhibitory effect of rapamycin-mediated autophagy activation on the circadian clock oscillators in U2OS cells. Collectively, our data indicate that autophagy activation attenuates the circadian clock oscillators in U2OS cells via the ATG5 pathway. • Autophagy activation results in damped circadian clock genes expression in U2OS cells. • 3-Methyladenine alleviates the inhibition of autophagy on BMAL1-Luc oscillations. • ATG5 knockout attenuates the inhibitory effect of autophagy activation on cell clock. [ABSTRACT FROM AUTHOR]

Directional solidification experiments of eutectic Al Fe alloys were carried out under different high magnetic field gradients. High magnetic field gradient changed the microstructure selection during solidification process, induced the solidification microstructure to undergo eutectic instability, cellular transition, single-phase instability, and dendrite transition, which is similar to the planar-cellular-dendritic crystal growth pattern transition usually induced by an increasing growth velocity without magnetic field. The single phase was proved to be formed through an independent nucleation mechanism during single-phase instability. The effect of high magnetic field gradient on solidification was analyzed. Through the coupling effect of magnetic force and Lorentz force on solute migration and diffusion during solidification, high magnetic field gradient triggered a constitutional supercooling at the front of solid-liquid interface, which led to the growth pattern transition. A solidification model of eutectic alloy under high magnetic field gradient was proposed, and the microstructure selection map of Al Fe alloy under gradient magnetic field was qualitatively drawn for the first time. This work proved that an alloy material with a microstructure usually obtained at high growth velocity can be obtained at a low growth velocity by applying a high magnetic field gradient, and suggested a new potential method for the future controlling of alloy structures and properties. [Display omitted] • High magnetic field gradient changes the microstructure selection during alloy solidification. • Critical solidification velocity for crystal growth pattern transition decreased by high magnetic field gradient. • Under high magnetic field gradient, the left boundary of coupled zone of Al Fe eutectic alloy moves right. • Coupling effect of Lorentz force and magnetic force induces constitutional supercooling during solidification. • High magnetic field gradient has a same effect as increasing solidification velocity on alloy solidification. [ABSTRACT FROM AUTHOR]

Using Tb 0.27 Dy 0.73 Fe 1.95 as a model alloy, we generate (Tb, Dy)Fe 2 and (Tb, Dy)Fe 3 phases with preferred orientations. We study the mechanism that determines the preferred crystal orientation of a peritectic alloy under high magnetic fields. Adjusting the preparation parameters yields four Tb 0.27 Dy 0.73 Fe 1.95 alloys with respective 〈110〉, 〈111〉, 〈112〉, and 〈113〉 directions of the peritectic (Tb, Dy)Fe 2 phase parallel to the high magnetic field. The 〈11 2 ¯ 0〉, 〈0001〉, 〈10 1 ¯ 0〉, and 〈10 1 ¯ 3 ¯ 〉 directions of the corresponding primary (Tb, Dy)Fe 3 phase are parallel to the magnetic field. We deduce the orientation relationships (1 ¯ 11)//(0001) and [110]//[11 2 ¯ 0] for the (Tb, Dy)Fe 3 and (Tb, Dy)Fe 2 phases. The growth velocity and high magnetic field do not change the orientation relationships of these two phases. The high magnetic field induces the rotation of the primary (Tb, Dy)Fe 3 phase and then affects the orientation of the peritectic (Tb, Dy)Fe 2 phase. Magnetic torque induces stacking of the {0001} plane perpendicular to the magnetic field, meaning the c -axis of the primary (Tb, Dy)Fe 3 phase aligns parallel to the field. At this time, the {111} plane of the (Tb, Dy)Fe 2 phase grows perpendicular to the magnetic field, as reflected in the preferred orientation of the (Tb, Dy)Fe 2 phase along the 〈111〉 direction. • Mechanism that determines the crystal orientation of a peritectic alloy under high magnetic fields was clarified. • There is a fixed orientation relationships between primary (Tb, Dy)Fe 3 and peritectic (Tb, Dy)Fe 2 phases. • Easy axis orientation of peritectic phase can be produced by high magnetic field during solidification. [ABSTRACT FROM AUTHOR]

[Display omitted] • A non-invasive rotating flow for bubble refinement is designed. • Bubble size decreases by rotating flow of liquid without using invasive parts. • Rotating flow causes the formation size of mother bubble to be small. • Turbulent shear stress and turbulent normal stress make mother bubble break into small daughter bubbles. Gas–liquid flow widely exists in industrial processes. Bubble refinement is of importance because smaller bubbles lead to higher efficiency of the gas–liquid interaction. Here, the novel rotating flow is designed for bubble refinement without using invasive parts. The drag force along the flow direction and the additional shear-lift force applied on the mother bubble allow it to detach from the orifice more easily with smaller size. In addition, the non-invasive rotating flow generates a large velocity gradient in both the shear and normal directions, resulting in turbulent shear and normal stress, causing the rising mother bubbles to break up in either the shear or normal direction. As a result, the number of bubbles increases to 408 compared to 9 under the static condition. Approximately 50% of the bubbles in the liquid are less than 3.60 mm in size and the Sauter mean bubble diameter is reduced from 10.45 to 4.77 mm, a decrease of 54.41%. The bubble refinement mechanism in the non-invasive rotating flow applies to other occasions where no invasive parts are needed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microstructural and mechanical anisotropy of CSAMed 7075 deposits were revealed. • As the tensile direction changes from X/Y to Z direction, UTS gradually decreases. • In a certain range of tensile direction, UTS of 7075 deposits can be predicted. • A possible mechanism to explain the anisotropy was proposed. In this work, microstructural and mechanical anisotropy in cold spray additively manufactured (CSAMed) 7075 Al deposits were studied in detail. For clarity, spray gun traverse direction, pass interval direction and deposition direction were defined as the X, Y and Z, respectively. Tensile tests for two different groups of samples were carried out in different orientations to study the in-plane and three-dimensional anisotropy of CSAMed 7075 Al deposits. Fracture morphology of the specimens was studied by optical microscopy (OM) and scanning electron microscopy (SEM). Transmission electron microscopy (TEM) was employed to examine particle–particle interface bonding. The results revealed that there exists a strong microstructural and mechanical anisotropy in the CSAMed deposits. The ultimate tensile strength (UTS) gradually decreased as the tensile direction changed from X/Y to Z direction. Further, crack propagation behavior was uniform in XY plane but a strong anisotropy was resulted in the planes that were perpendicular to XY plane. The underlying reason and possible mechanism related to this anisotropy was discussed in detail. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is an endocrine-disrupting compound that impairs testosterone synthesis in male mammals. A circadian clock gene deficiency leads to diminished fertility and even infertility in male mice. However, whether circadian clock signaling pathways mediate the suppressive effect of BPA on testosterone synthesis in Leydig cells (LCs) remains unknown. The present study aims to detect the effect of BPA on cellular circadian clock and testosterone synthesis in mouse LCs, and examine the mechanisms underlying NR1D1 signaling. BPA treatment significantly attenuated the transcription levels of Nr1d1 and steroidogenic genes (Hsd3b2 and Hsd17b3) in TM3 cells, but increased other circadian clock gene levels (Per2 and Dbp). BPA treatment also significantly downregulated NR1D1 and StAR protein expression, but upregulated BMAL1 protein expression in TM3 cells. Furthermore, there was a marked decline in testosterone production in BPA-treated TM3 cells. Intraperitoneal injection of BPA profoundly reduced NR1D1 and StAR protein levels and steroidogenic gene transcription levels (Cyp11a1 , Hsd3b2 , and Hsd17b3), while enhancing BMAL1 protein and other circadian clock gene (Per2 and Dbp) levels in mouse testes. Notably, serum testosterone levels were also drastically reduced in BPA-treated mice. Moreover, SR9009, an NR1D1 agonist, augmented testosterone production in TM3 cells via elevated expression of steroidogenic genes (StAR, Cyp11a1 and Hsd17b3). Conversely, Nr1d1 knockdown inhibited testosterone accumulation and attenuated steroidogenic gene expression. Moreover, treatment with SR9009 partially reversed the BPA effect on the circadian clock and testosterone production. Taken together, our study demonstrates that BPA perturbs testosterone production, at least partially, via inhibiting NR1D1 signaling in LCs. • BPA attenuates testosterone synthesis in Leydig cells in vivo and in vitro. • BPA administration alters PER2::LUC oscillations in primary Leydig cells. • SR9009, an agonist of NR1D1, augments testosterone production in TM3 cells. • Knock-down of Nr1d1 represses testosterone production in TM3 cells. • BPA perturbs testosterone synthesis via inhibiting NR1D1 signaling in Leydig cells. [ABSTRACT FROM AUTHOR]