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With the widespread use of nuclear energy, the storage of surplus spent fuel has emerged as a critical issue that needs to be solved, especially for the efficient absorption of neutron radiation and secondary γ-rays generated by spent fuel produced when 10B absorbs neutrons. In this work, B4C/Al and W/B4C/Al coating were prepared on 316 L stainless steel by cold spraying. The microstructure and tensile properties of the coatings were investigated. The performance of the thermal neutron and secondary γ-rays absorption of the two coatings were simulated using the Monte Carlo approach. The results indicated that, compared to the B4C/Al coating, the W/B4C/Al coating exhibited better mechanical properties due to the tamping effect of the W particles. In addition, the secondary γ-rays absorption property was improved due to the addition of W. [ABSTRACT FROM AUTHOR]

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]

Al-based metal matrix composites (MMCs) coatings, prepared by cold spray, have been extensively investigated in recent years. However, only a fraction of the ceramic reinforcement particles could be retained in the final deposit due to the rebound of the hard ceramic particles. Thus, improving the ceramic content in MMCs has been a longstanding issue. To address this issue, for the first time, the effect of particle size of the metal matrix as well as the reinforcement phases on the retention of ceramic particles (in the composite) was simultaneously studied. For this purpose, 12 different kinds of mechanically blended Al/B4C feedstock powders (with different particle sizes) were deposited by cold spray to prepare composite coatings. The results showed that the content of B4C in the prepared Al/B4C coating increases from ~ 20 to ~ 30 vol.% with the decrease in Al particle size from 42 to 11 µm. Finally, a mechanism, elaborating the influence of metal matrix particle size on the retention of ceramic particles in the coating, was proposed. The hardness test for selected Al/B4C composite coatings was performed, which is consistent to the change trend of B4C content. [ABSTRACT FROM AUTHOR]

In this work, a bifunctional ligand 2,2′-disulfonic acid benzidine (H2L) was selected, and we adopted a mixed ligand strategy, in which the ligand reacted with 2,2′-bipyridine and 1,10-o-phenanthroline, where two new silver-based coordination polymer materials [Ag2(2,2′-bipy)2L]·H2O (BAg-1) and [Ag2(phen)2L] (BAg-2) were obtained. BAg-1 was zero-dimensional, which could interconnect with one-dimensional hydrogen bonds to form a three-dimensional stacking structure, while BAg-2 was a one-dimensional chain structure, and the one-dimensional chains formed a two-dimensional planar structure through hydrogen bonding between the sulfonic acid group and the amino group. Their proton conductivity reached a high level among the coordination polymers at 98% relative humidity (RH) and 90 °C, where their proton conductivity values were 0.455 × 10−4 S cm−1 (BAg-1) and 1.09 × 10−4 S cm−1 (BAg-2), respectively. Combining their respective single crystal data with the results of Hirshfeld surface analysis, water adsorption experiments, and activation energy calculations, we determined their proton conduction pathways and mechanisms. The results showed that the abundant hydrogen bond chains and hydrogen bond networks co-constructed using sulfonic acid groups, amino groups and crystal water molecules in the framework and numerous uncoordinated sulfonic acid groups as proton carriers in the material were the reasons for efficient proton transfer. [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]

Using uniform carbon nanospheres as sacrificial templates, gold nanoparticle-modified ZnO@ In 2 O 3 hollow nanospheres with controlled dimensions and porous architectures were successfully synthesized through water bath, hydrothermal and chemical reduction methods. Gas sensing evaluation revealed that the Au-decorated ZnO@ In 2 O 3 hollow nanostructures exhibited a dramatically amplified response up to 14.8 when exposed to 10 ppm formaldehyde analyte at room temperature. Furthermore, multifaceted performance benefits of Au-decorated ZnO@ In 2 O 3 over single-phase ZnO, Au-ZnO, ZnO@ In 2 O 3 heterojunction-based composites were observed, including excellent selectivity towards formaldehyde even in complex gas mixtures; tremendous sensitivity enhancement stemming from synergies between efficient gas diffusion through hollow heterojunction nanospheres and accelerated surface reactions at catalytically-active Au sites; and rapid, fully-reversible response/recovery time of 32 s and 42 s, respectively. In-depth investigations were conducted into the fundamental sensing mechanisms enabling formaldehyde detection using AC impedance spectroscopy, in situ diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS), and density functional theory (DFT) computational modeling analyses. • The hollow Au-ZnO@In 2 O 3 based sensor presents high response and excellent selectivity to formaldehyde under UV-LED at 20 °C. • The hollow Au-ZnO@In 2 O 3 based sensor displays shorter response and recovery time (32 s and 42 s) to 10 ppm formaldehyde. • In-situ DRIFTS confirms that the oxidation of HCHO by the adsorbed O 2 could be significantly enhanced by UV light. • DFT calculations indicate that the formed heterojunctions enhance the adsorption ability and charge transfer of the sensors. [ABSTRACT FROM AUTHOR]

The effects of molecular weight (Mw) and content of poly(vinyl acetate) (PVAc) on the crystallization behaviors, competing crystallization of homocrystallites and stereocomplex crystallites (SCs), crystalline structure, and mechanical properties of poly(L-lactic acid) (PLLA)/poly(D-lactic acid) (PDLA) blends were investigated. The crystallization of PLLA/PDLA component is accelerated after the addition of low-Mw PVAc and is suppressed with high-Mw PVAc. The ability of SC formation is enhanced via blending with PVAc, irrespective of its Mw, and becomes prominent with low-Mw PVAc. The exclusive SCs are obtained in the blends with 30 mass % low-Mw PVAc. The improvement in thermomechanical property above 170 °C is ascribed to the enhancement of SC content. This work presents guidance for achieving the melt processability of SC-PLA, thus proving their potential as a high-performance substitute for conventional plastics. [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]

Stereocomplexable polylactide (sc-PLA) with improved thermomechanical performance had been prepared by melt compounding of poly(L-lactide) (PLLA), poly(D-lactide) (PDLA), and nanosilica. The silica nanoparticles dispersed evenly in the sc-PLA matrix and there were no air bubbles because of good compatibility between nanosilica and sc-PLA. The aggregates size of nanosilica increased with increasing nanosilica content. The introduction of nanosilica facilitated the formation of stereocomplex, which was manifested as the degree of crystallinity of sc-PLA increased from 17.0 to 24.3% as the nanosilica content increased from 0 to 10 wt%. Thermal stability of sc-PLA was greatly improved by adding nanosilica, and the onset of decomposition temperature of sc-PLA/silica nanocomposites was ~33 °C higher than that of neat sc-PLA. Superior storage modulus was found for sc-PLA/silica nanocomposites compared to neat sc-PLA. The tensile strength and modulus of sc-PLA nanocomposites were greatly improved by the addition of nanosilica, but the elongation at break decreased. [ABSTRACT FROM AUTHOR]

Due to the high strength of the nickel‑aluminum bronze (NAB), the cold spray deposition efficiency of the NAB powders was less than satisfactory. To improve the deformation behavior of powder, different heat treatment strategies were adopted for gas atomized NAB powders and then the heat-treated powders were deposited on NAB substrates using a high-pressure cold spray system. For various powders and their corresponding deposits, a series of related characterizations were performed. The results indicate that the microstructure of the gas-atomized powder was mainly composed of martensitic β′ and bainite α with high hardness, resulting in low deposition efficiency and poor bonding between particles and particles in the prepared deposits. An effective technique of heat treatment can eliminate the non-equilibrium structure in the gas atomized powder, reduce the hardness of the powder, and significantly improve the deposition efficiency and enhance particle interface bonding. • Nickel‑aluminum bronze(NAB) powders using for cold spray were heat-treated. • The effects of heat treatment on microstructure of NAB powders were studied. • Heat treatment can eliminate NAB powder's non-equilibrium microstructure. • Powder heat treatment can improve deposition efficiency and particle bonding. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEA), a mycotoxin, is known to impair reproductive capability by disrupting the synthesis and secretion of testosterone by Leydig cells (LCs), although the mechanism is unknown. Robust rhythmicity of circadian clock and steroidogenic genes were identified in LCs. The aim of this study was to examine whether ZEA significantly attenuated the transcription of core clock genes (Bmal1, Dbp, Per2, and Nr1d1) as well as steroidogenic genes (StAR, Hsd3b2, and Cyp11a1) in mouse testis Leydig cell line (TM3). Western blotting confirmed declines in BMAL1, NR1D1, and StAR protein levels. ZEA also suppressed secreted testosterone levels. In primary LCs, isolated from PER2::LUCIFERASE reporter gene knock in mice, ZEA diminished the amplitude of PER2::LUC expression, and induced a phase shift and period extension. In primary LCs, ZEA also suppressed the expression levels of core clock and steroidogenic genes, reduced protein levels of BMAL1, and decreased testosterone secretion. In vivo expression of core clock and steroidogenic genes were reduced in testes of mice exposed to ZEA for 1 week leading to decreased serum testosterone levels. In summary, data suggest that ZEA may impair testosterone synthesis through attenuation of the circadian clock in LCs culminating in reproductive dysfunction in male mammals. [ABSTRACT FROM AUTHOR]

The aim of this study was to prepare a new blend system by blending equimolar poly(L-lactic acid) (PLLA) and poly(D-lactide acid) (PDLA) with poly(butylene adipate-co-terephthalate) (PBAT) and to form stereocomplex polylactide (sc-PLA) during blending process. Then, sc-PLA would improve the performance of PBAT without compromising its biodegradability. Torque-time curve, differential scanning calorimetry (DSC), and wide angle X-ray diffraction (WAXD) measurements indicated that only sc-PLA formed in PBAT matrix. The phase morphology showed that sc-PLA particles were uniformly dispersed in PBAT matrix, and the sizes were independent of their contents. The rheological properties of PBAT were significantly enhanced by addition of sc-PLA, especially after the formation of a percolation network structure. With the increase of sc-PLA content, the blends displayed increased yield strength and modulus and decreased elongation at break and tensile strength. The sc-PLA particles could reinforce PBAT matrix. Compared with pure PBAT, the heat resistance of PBAT/sc-PLA blends was improved. [ABSTRACT FROM AUTHOR]

The hollow ZnO @ TiO 2 heterostructured nanospheres were synthesized by hydrothermal method using carbon nanospheres as sacrificed templates. With UV activation, the response of ZnO @ TiO 2 based chemiresistive-type sensors to 10 ppm formaldehyde is 11.02 at room temperature which is 5.48 times larger than that of the pure hollow ZnO. The response and recovery time significantly reduced to 14 s and 16 s. Selectivity, stability and repeatability of the hollow ZnO @ TiO 2 based sensor under UV-activation have also been examined. The sensing mechanism of the sensor to formaldehyde have been investigated by AC impedance spectroscopy, in-situ DRIFTS, and DFT theoretical calculation. • The hollow ZnO@TiO 2 based sensor presents high response and excellent selectivity to formaldehyde under UV-LED at 20 °C. • The hollow ZnO@TiO 2 based sensor displays shorter response and recovery time (14 s and 16 s) to 5 ppm formaldehyde. • In-situ DRIFTS confirms that the oxidation of HCHO by the adsorbed O 2 could be significantly enhanced by UV light. • DFT calculations indicate that the formed heterojunctions enhance the adsorption ability and charge transfer of the sensors. [ABSTRACT FROM AUTHOR]

[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]

7075 aluminum alloy deposits were fabricated using a solid-state additive manufacturing (AM) technology called laser-assisted cold spray (LACS). The effect of laser power on the microstructure evolution and mechanical property in the LACSed 7075 deposits was investigated. The microstructure of all deposits was analyzed by optical microscopy (OM), X-ray diffraction (XRD), and scanning electron microscopy (SEM) attached with energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD) systems. Pull-off adhesion, microhardness, and tensile tests were performed to assess their mechanical behaviors. The deposits showed a virtually linear increase in thickness with increased laser power and a minimum porosity of about 0.2%. With the accelerated diffusion of solute elements in deposits, lamellar η phase – Mg(Zn, Cu, Al) 2 and Al 7 Cu 2 Fe precipitated along grain boundaries at 2.6 kW eventually. Meanwhile, significant grain growth and recrystallization were initiated at the severely deformed prior-particle interfaces. All the LACSed deposits exhibited a noticeable increase in adhesion strength and a slight decrease in microhardness compared to the CSed one. The ultimate tensile strength (UTS) and elongation to fracture (EL) were improved by up to ∼46% and ∼35% in LACSed 7075 deposits. The relationship between mechanical properties and microstructure and the contribution of underlying strengthening mechanisms involved in the LACS process were then thoroughly discussed. • Crack-free 7075 deposits were made through laser-assisted cold spray. • The laser improved mechanical properties and particle bonding of deposits. • Grain boundary strengthening and defect control play vital roles in LACS. [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]

Invited for the cover of this issue are the groups of Lin Du and Qi‐Hua Zhao at Yunnan University. The image depicts astronauts as protons moving along the hydrogen‐bond network in the channel of Eu‐ETTB/Gd‐ETTB. Read the full text of the article at 10.1002/chem.202202154. [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]

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]

Au-decorated hollow TiO 2 nanospheres were synthesized via a template method subsequently followed by the reduction of Au nanoparticles decorated on the surface of TiO 2. The diameter of the hollow TiO 2 nanospheres is 150–200 nm and the thickness of the shell layer is 10–15 nm. The particle size of Au nanoparticles on the surface of TiO 2 nanospheres is about 15 nm. The 1 mol% Au-decorated hollow TiO 2 nanospheres based chemiresistive-type sensor exhibited a much improved sensing performance to formaldehyde under Ultraviolet (UV) irradiation at room temperature. The response of the sensor to 5 ppm formaldehyde is about 8.5, which is three times higher than that of the pure hollow TiO 2 nanospheres based one. The response and recovery time of the sensor to 5 ppm formaldehyde is 36 s and 110 s, respectively. The mechanisms of both electronic and chemical sensitizations induced by Au nanoparticles and the hollow structure were proposed for the enhanced sensing properties. • Au-decorated hollow TiO 2 nanospheres were prepared using water bath method and the followed chemical reduction process. • UV-light irradiation lowered the working temperature of Au-decorated hollow TiO 2 nanospheres to room temperature. • The 1 mol% Au/TiO 2 nanospheres based sensor presents highest response, shortest response time and excellent selectivity to formaldehyde. [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]

• Gas sensing materials hollow TiO 2 @SnO 2 heterojunction nanospheres were prepared using hydrothermal method. • The TiO 2 @SnO 2 heterojunctions based sensor presents a better response to UV-LED. • The gas sensor exhibits high response and excellent selectivity to formaldehyde under UV-LED at room temperature. • The gas sensor displays shorter response time and recovery time. Hollow TiO 2 @SnO 2 nanospheres were synthesized via a hydrothermal process. Comparing to pure hollow TiO 2 nanospheres, the hollow TiO 2 @SnO 2 heterojunction nanospheres based sensor exhibited better sensing properties to formaldehyde under Ultraviolet (UV) irradiation at room temperature. The response time and recovery time were 20 s and 56 s, respectively, which are reduced compared to the pure one. The enhanced sensing properties could be ascribed to the formation of heterojunction between SnO 2 and TiO 2 together with hollow nanosphere architectures. The decorated TiO 2 nanocrystals are even more depleted at the shallow Debye region which is equivalent to the reduction in the effective particle size of TiO 2 significantly contributing to the enhanced response. After the targeted gases were removed, the chemisorbed oxygen on the surface of the metal oxides trapped electrons to the surface of the heterojunction sample. This process can also be promoted by energy barriers, which can explain the faster recovery speed of the heterojunction based sensor compared to that of the pure hollow TiO 2 based one. [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]

To improve the wear resistance of commercial AZ31 Mg alloy, two types of dense and thick composite coatings were prepared on AZ31 Mg alloy by means of cold-spray technology. For this purpose, Al 2 O 3 particles with different morphology (round and irregular) were separately added to the Al 5Si feedstock. The morphological effects of Al 2 O 3 on the microstructure, adhesion strength, hardness, and tribological properties of the coatings were comprehensively studied. Microstructural features of the coatings were examined by means of optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD). The analysis reveals that most of the grains in both coatings are ultrafine, and approximately half of the total grain boundary length is composed of low-angle grain boundaries. Wear, hardness, and pull-off tests showed that both types of Al 2 O 3 particles have a positive impact on porosity, adhesion, hardness, and wear resistance of the composite coatings. Compared to round Al 2 O 3 , irregular Al 2 O 3 particles exhibit better retention in the coating, thereby resulting in a higher hardness and wear resistance. • Al-5Si/Al 2 O 3 composite coatings were deposited on AZ31 Mg by cold spray. • The effects of Al 2 O 3 morphology on the coating were studied. • Irregular Al 2 O 3 particles exhibit better retention in the coating. • Irregular Al 2 O 3 particles can better increase coating's wear resistance. [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]

Dynamic recrystallization (DRX) is an important grain refinement mechanism to fabricate steels with high strength and high ductility (toughness). The conventional DRX mechanism has reached the limitation of refining grains to several microns even though employing high-strain deformation. Here we show a DRX phenomenon occurring in the dynamically transformed (DT) ferrite, by which the required strain for the operation of DRX and the formation of ultrafine grains is significantly reduced. The DRX of DT ferrite shows an unconventional temperature dependence, which suggests an optimal condition for grain refinement. We further show that new strategies for ultra grain refinement can be evoked by combining DT and DRX mechanisms, based on which fully ultrafine microstructures having a mean grain size down to 0.35 microns can be obtained without high-strain deformation and exhibit superior mechanical properties. This study will open the door to achieving optimal grain refinement to nanoscale in a variety of steels requiring no high-strain deformation in practical industrial application. [ABSTRACT FROM AUTHOR]

Hot deformation behavior of an equiatomic CoCrFeMnNi high entropy alloy was investigated. Hot compression tests were carried out at various temperatures ranging from 800 °C to 1000 °C at different strain rates from 0.001s −1 to 1s −1 . Stress-strain curves indicated softening due to dynamic recrystallization (DRX) under most conditions. Flow stress analysis was carried out by using Arrhenius type hyperbolic-sine relationship, and a linear dependence of flow stress on Zener-Hollomon parameter ( Z ) was found. Based on the flow stress analysis, a constitutive equation was formulated for describing interdependency between deformation temperature, strain rate, flow stress and strain. The estimated apparent activation energy (Q) ∼350 kJmol -1 for the hot deformation was approximately similar to the activation energy for diffusion of the slowest diffusing element Ni in this alloy. Microstructural observations were carried out by electron backscatter diffraction (EBSD). The EBSD analysis indicated that the DRX grains nucleated along initial grain boundaries resulting in necklace like structures. The fraction and size of DRX grains showed a strong dependence on Z . Textures of deformed and DRX grains were found to be similar to each other, but rather weak. This feature could be attributed to the nucleation of dynamic recrystallization without any preferential orientation selection. [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: The Rev-erbα gene is regarded as a circadian clock gene and clock-regulated gene which regulates the circadian transcriptional/translational loop in a subtle way. Here, we first detected the circadian oscillation in mature granulosa cells from antral follicles using a real-time monitoring system of Per2 promoter activity with the addition of FSH. Then we used GSK4112, an agonist ligand of Rev-erbα, to investigate the function of Rev-erbα. GSK4112 treatment significantly reduced the Per2-dLuc amplitude and induced the Per2 oscillation phase advance shift. GSK4112 significantly inhibited Bmal1 mRNA expression, whereas it did clearly stimulate expression of StAR mRNA in a dose-dependent manner. Our data are the first to show the Rev-erbα function in the steroid biosynthesis of rat granulosa cells, and to suggest that Rev-erbα may coordinate circadian rhythm and metabolism in rat ovaries. [Copyright &y& Elsevier]

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]

Abstract The present work provides an insight into the phase-specific mechanical properties of the microstructural constituents in a quenching and partitioning (Q&P) processed steel. The mechanical properties of carbon-enriched retained austenite and low-carbon primary martensite were studied by nano-indentation tests. The results show that the hardness of the carbon-enriched retained austenite is slightly higher than or, at least, comparable to that of the low-carbon primary martensite. The evidence of the strain hardening due to the transformation of retained austenite to twinned martensite during the nano-indentation compression is also shown. [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]

Due to its low process temperature, cold spray (CS) is considered an excellent metallization method to deposit thick coatings on temperature-sensitive polymeric materials. However, in previous studies, the properties (such as electrical conductivity and adhesion strength) of the cold sprayed metallic coating on the polymeric substrate are relatively low. To address this issue, large-sized spherical Al 2 O 3 particles were added into Al powder in different proportions (i.e. 0, 10, 20, 30, 40 wt%) to prepare dense Al-Al 2 O 3 coatings on PEEK by CS. The effect of Al 2 O 3 content on microstructure, deposition efficiency (DE), microhardness, electrical conductivity, and adhesion strength of Al-Al 2 O 3 coatings was systematically studied. Results show that adding an appropriate amount of Al 2 O 3 to the feedstock can effectively improve the Al-Al splat bonding, electrical conductivity, and adhesion strength of the prepared coating on PEEK substrate, which is attributed to the 'in-situ tamping effect' of spherical Al 2 O 3 particles. Moreover, the molecular structure of the substrate was not damaged or affected after the impact of Al and Al 2 O 3 particles during the CS process. The prepared Al-Al 2 O 3 coating exhibits better performance and provides a novel approach for polymer metallization. [Display omitted] • Al-Al 2 O 3 coatings with different Al 2 O 3 content were deposited on PEEK via CS. • Adding Al 2 O 3 particles can improve electrical conductivity and adhesion strength. • The structure of PEEK was well retained after the impact of Al 2 O 3 particles. • Deposition mechanism of Al-Al 2 O 3 coating on PEEK substrate was discussed. [ABSTRACT FROM AUTHOR]

The nuclear receptor REV-ERBα links circadian rhythms and numerous physiological processes, but its physiological role in ovaries remains largely unknown. The aim of this study was to determine the potential role of REV-ERBα in the regulation of the transcription of its putative target genes in granulosa cells (GCs) prepared from Per2-destablized luciferase ( dLuc) reporter gene transgenic rats. Alas1, Ppargc1a, and Il6 were chosen as representatives for genes analysis. A real-time monitoring system of Per2 promoter activity was performed to detect Per2-dLuc circadian oscillations. Two agonists (GSK4112, heme) and an antagonist (SR8278) of REV-ERBα as well as Rev-erbα siRNA knockdown were used to identify its target genes. Clear Per2-dLuc circadian oscillations were generated in matured GCs after synchronization with GSK4112 or SR8278. GSK4112 treatment lengthened and SR8278 treatment shortened the period of circadian oscillations in matured GCs stimulated with or without luteinizing hormone (LH). GSK4112 showed an inhibitory effect on the amplitude of circadian oscillations and caused an arrhythmic expression of canonical clock genes. SR8278 also had a subtle effect on their daily expression profiles, but the treatment resulted only in the arrhythmic expression of Rev-erbα. These findings indicate the functional biological activity of REV-ERBα in response to its ligands. Its natural ligand heme further elongated the period of circadian oscillations and alleviated their amplitudes in GCs cultured with LH. Heme treatment also repressed the expressions of clock genes, Alas1, Il6, and Ppargc1a. Rev-erbα knockdown up-regulated these transcript levels. Collectively, these data extend the recent finding to rat GCs and demonstrate that REV-ERBα represses the expressions of Alas1, Ppargc1a, and Il6, providing novel insights into the physiological significance of REV-ERBα in ovarian circadian oscillators. [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]

Cold spray (CS) is an emerging deposition technique for the metallization of polymer material to improve its thermal and electrical properties. In this study, pure Al coatings were deposited on polyether ether ketone (PEEK) substrate by CS. Further, the influence of accelerating gas temperature on microstructure and properties (i.e. deposition efficiency, adhesive strength, electrical conductivity, thermal diffusivity and hardness distribution) of the prepared coatings was systematically investigated. Energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), the quantitative analysis of oxygen content and Raman spectra results revealed that the prepared coatings were composed of crystalline metallic Al without obvious oxide phases. Moreover, the polymer structure of PEEK substrate remained intact after high-velocity and high-temperature impact during the CS process. The adhesive strength, electrical conductivity and thermal diffusivity of the Al coating increased with increasing accelerating gas temperature. At the accelerating gas temperature of 380 °C, a dense and thick Al coating with high adhesive strength was obtained in just two deposition passes. Moreover, multi-pass tests (at high nozzle traverse speed) were performed to understand the deposition mechanism of Al coating on PEEK substrate through analyzing cross-section/surface morphology of samples with different thicknesses. Finally, the deposition mechanism of cold sprayed Al coating on PEEK was proposed. [Display omitted] • PEEK was metallized with Al via CS to enhance electrical and thermal properties. • The structure of Al and PEEK remained intact during the CS process. • A dense and thick Al coating was deposited on PEEK at high gas temperature. • Electrical and thermal properties of Al coating increased with gas temperature. • The deposition process of Al coating on PEEK was discussed and summarized. [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]

We report evidence of a displacive phase transformation from retained austenite to martensite during preparation of quenched and partitioned steel micro-pillars by using a focused ion beam (FIB) technique. The BCC phase produced by the FIB damage was identified as martensite. The invariant-plane strain surface relief associated with the martensitic transformation was observed in the retained austenite phase immediately after a FIB scan of the surface with the Ga+ ion beam. Use of a low acceleration voltage appears to lower the probability of the phase transformation, while a decrease of the acceleration voltage will result in an increase of the total milling time required to prepare a micro-pillar. This report addresses challenges related to the preparation of austenite micro-pillars by a conventional FIB technique. Image 1 • Austenite transforms to martensite during fabrication of Q&P steel micro-pillars. • Invariant-plane strain surface relief due to the transformation is shown after a FIB scan. • The parent austenite and product martensite had a K–S orientation relationship. • The product BCC phase produced by the FIB damage is identified as martensite. • A low acceleration voltage lowers the probability of the phase transformation. [ABSTRACT FROM AUTHOR]