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The sensitivity of grain boundary (GB) cracks often limits the high-temperature plasticity of superalloys. The 750 ℃ tensile deformation of fine-grained Ni-Co based wrought superalloys was observed in situ using a scanning electron microscope (SEM) equipped with an electron backscatter diffraction (EBSD) probe to clarify the texture formation and GB response. The GB stress concentration depends on the grain orientation and slip system alignment on both sides. This reflects the ability of GBs to cope with deformation incompatibility. This study provides valuable insights for predicting the failure of polycrystalline superalloys and offers new ideas for microstructure evaluation and GB design.

The solution-treated second-generation single crystal (SX) superalloys underwent hot isostatic pressing (HIP) at 1316 °C and 105 MPa for varying durations. This study investigates the effect of HIP on micropores and stress-rupture behavior under conditions of 980 °C and 250 MPa. The results illustrate that the application of HIP treatment significantly reduces the porosity and volume of micropores, thereby increasing the rupture life of the alloys. With the disappearance of micropores, the crack initiation site shifts from the micropores to the γ/γʹ interface, resulting in reduced crack dimensions and decelerated propagation. Consequently, the smaller size of cracks in HIPed specimens slow down fracture. Nonetheless, the crack propagation pattern remains consistent: cracks expand perpendicular to the stress axis, connecting with cracks at other heights via secondary cracks along the direction.

Massive access of renewable energy has prompted demand-side distributed resources to participate in regulation and improve flexibility of power systems. With large-scale access of massive, decentralized, and diverse distributed resources, demand-side market members have transformed from traditional “consumers” to “prosumers”. To explore the distributed transaction model of prosumers, in this paper, a multi-prosumer distributed transaction model is proposed, and the Conditional Value-at-Risk (CVaR) theory is applied to quantify potential risks caused by the stochastic characteristics inherited from renewable energy. First, a prosumer model under constraints of the distribution network including photovoltaic units, fuel cells, energy storage system, central air conditioning and flexible loads is established, and a multi-prosumer distributed transaction strategy is proposed to achieve power sharing among multiple prosumers. Second, a prosumer transaction model based on CVaR is constructed to measure risks inherited from the uncertainty of PV output within the prosumer and ensure safety of system operation in extreme PV output scenarios. Then, the alternating direction multiplier method (ADMM) is utilized to solve the constructed model efficiently. Finally, distributed transaction costs of prosumers are distributed fairly based on the generalized Nash equilibrium to maximize social benefits. Simulation results show the multi-prosumer distributed transaction mechanism established under the proposed generalized Nash equilibrium method can encourage power sharing among prosumers, increasing their own income and social benefits. Also, the CVaR can assist decision making of prosumers in weighting the risks and benefits, improving system resilience through energy management of prosumers.

Hydrogen energy is a promising solution to reaching carbon emissions peak and carbon neutrality. With the development of hydrogen energy devices, coupling hydrogen energy with renewable energy for power generation can compensate for the intermittency and instability of renewable energy. Furthermore, the two-stage coordinated planning of integrated energy system (IES) and electricity-hydrogen integrated energy system (EHIES), compared to independent planning, can help generate additional benefits and reduce carbon emissions. Therefore, this paper proposes a coordinated planning of EHIES considering lifecycle carbon emissions. In the first stage, aiming to minimize investment costs, network losses, voltage deviations, and lifecycle carbon emissions, the equipment capacity and location of EHIES is determined. The life cycle assessment (LCA) method is used to quantify the lifecycle carbon emissions of the EHIES, preparing for the coordinated operation in the second stage. Subsequently, in the second stage, using carbon emissions flow to allocate users’ responsibility for emissions, the carbon emissions per unit electricity of the IES system are calculated. With the optimal cost of independent operation for IES and EHIES as the coordinated operation objective, the alternating direction method of multipliers (ADMM) is employed for sequential solution, obtaining the carbon emissions reduction amount, and iteratively updating until convergence. Finally, the effectiveness of the proposed method is verified by using the IEEE 33-bus power distribution network (PDN) and natural gas 6 node systems. The results show that compared to independent planning, the two-stage coordinated planning method reduces the overall operating cost of IES by 3.81% and decreases carbon emissions by 15.89%. This method is effective in reducing the carbon emissions of IES.

Following publication, concerns were raised regarding the peer-review process related to the publication of this article [...]

Emotional false memories are the erroneous recollection of events accompanied by an emotional experience. In high-risk domains like psychotherapy and the legal system, emotional false memories are of particular importance. Despite the systematic research conducted on emotional false memories in recent years, findings remain contradictory. Some studies have suggested that negative emotion reduces false memories, while others have suggested that negative emotion increases false memories. Research has mainly employed words and pictures as experimental stimuli, and studies using both types of memory stimuli are reviewed here. From this examination, it emerged that the main reasons for contradictory findings are as follows: (1) different materials have varying effects on inducing false memories, with pictures demonstrating a memory advantage compared to words; (2) recall and recognition tests have been used interchangeably, leading to different false-memory effects depending on the memory test employed; and (3) different studies have adopted different levels of control over valence and arousal when manipulating emotional variables. Future studies should distinguish between the use of different memory materials, examine specific differences in recall and recognition tests, and measure the impact of specific emotions on false memory beyond the dimensions of valence and arousal.

The resource recovery and reuse of precious metal-laden wastewater is widely recognized as crucial for sustainable development. Superalloy electrolytes, produced through the electrolysis of superalloy scrap, contain significant quantities of precious metal ions, thereby possessing substantial potential for recovery value. This study first explores the feasibility of utilizing fungi to treat Superalloy electrolytes. Five fungi resistant to high concentrations of heavy metals in electrolytes (mainly containing Co, Cr, Mo, Re, and Ni) were screened from the soil of a mining area to evaluate their adsorption characteristics. All five fungi were identified by ITS sequencing, and among them, Paecilomyces lilacinus showed the best adsorption performance for the five heavy metals; therefore, we conducted further research on its adsorption characteristics. The best adsorption effect of Co, Cr, Mo, Re, and Ni was 37.09, 64.41, 47.87, 41.59, and 25.38%, respectively, under the conditions of pH 5, time 1 h, dosage 26.67 g/L, temperature 25–30°C, and an initial metal concentration that was diluted fivefold in the electrolyte. The biosorption of Co, Mo, Re, and Ni was better matched by the Langmuir model than by the Freundlich model, while Cr displayed the opposite pattern, showing that the adsorption process of P. lilacinus for the five heavy metals is not a single adsorption mechanism, but may involve a multi-step adsorption process. The kinetics study showed that the quasi-second-order model fitted better than the quasi-first-order model, indicating that chemical adsorption was the main adsorption process of the five heavy metals in P. lilacinus. Fourier transform infrared spectroscopy revealed that the relevant active groups, i.e., hydroxyl (-OH), amino (-NH2), amide (- CONH2), carbonyl (-C = O), carboxyl (-COOH), and phosphate (PO43–), participated in the adsorption process. This study emphasized the potential application of P. lilacinus in the treatment of industrial wastewater with extremely complex background values.

Laser cladding provides advanced surface treatment capabilities for enhancing the properties of components. However, its effectiveness is often challenged by the formation of hot cracks during the cladding process. This study focuses on the formation mechanism and inhibition of hot cracks in a novel cobalt-based alloy (K688) coating applied to 304LN stainless steel via laser cladding. The results indicate that hot crack formation is influenced by liquid film stability, the stress concentration, and precipitation phases. Most hot cracks were found at 25°–45° high-angle grain boundaries (HAGBs) due to the high energy of these grain boundaries, which stabilize the liquid film. A flat-top beam, compared to a Gaussian beam, creates a melt pool with a lower temperature gradient and more mitigatory fluid flow, reducing thermal stresses within the coating and the fraction of crack-sensitive, high-angle grain boundaries (S-HAGBs). Finally, crack formation was significantly inhibited by utilizing a flat-top laser beam to optimize the process parameters. These findings provide a technical foundation for achieving high-quality laser cladding of dissimilar materials, offering insights into optimizing process parameters to prevent hot crack formation.

Comparable investigation of pore-induced defects during in-phase (IP) and out-of-phase (OP) thermo-mechanical fatigue (TMF) were conducted on fourth-generation single crystal superalloy. It was discovered that recrystallizations and deformation twins would take shape near micro-pores at IP and OP cycling, respectively. High-resolution observation uncovered that the increasing a/6〈112〉 twinning dislocations and more frequent activation of 〈112〉{111} viscous slipping during OP-TMF accounted for twinning nucleation. Atom-scale mapping additionally disclosed the dual effect of Re, Co, and Cr in facilitating twinning formation and impeding of partial dislocations movement. It was deemed that the accumulation of pore-induced twins caused the premature fracture of alloy during OP-TMF.

Abstract Background Type 2 diabetes mellitus is a global health problem. It often leads to a decline in the differentiation capacity of myoblasts and progressive loss of muscle mass, which in turn results in deterioration of skeletal muscle function. However, effective therapies against skeletal muscle diseases are unavailable. Methods Skeletal muscle mass and differentiation ability were determined in db/+ and db/db mice. Transcriptomics and metabolomics approaches were used to explore the genetic mechanism regulating myoblast differentiation in C2C12 myoblasts. Results In this study, the relatively uncharacterized solute carrier family gene Slc2a6 was found significantly up-regulated during myogenic differentiation and down-regulated during diabetes-induced muscle atrophy. Moreover, RNAi of Slc2a6 impaired the differentiation and myotube formation of C2C12 myoblasts. Both metabolomics and RNA-seq analyses showed that the significantly differentially expressed genes (e.g., LDHB) and metabolites (e.g., Lactate) during the myogenic differentiation of C2C12 myoblasts post-Slc2a6-RNAi were enriched in the glycolysis pathway. Furthermore, we show that Slc2a6 regulates the myogenic differentiation of C2C12 myoblasts partly through the glycolysis pathway by targeting LDHB, which affects lactic acid accumulation. Conclusion Our study broadens the understanding of myogenic differentiation and offers the Slc2a6-LDHB axis as a potential therapeutic target for the treatment of diabetes-associated muscle atrophy. Video abstract

Due to the excellent combination of strength and ductility, eutectic high entropy alloys (EHEAs) are of great interests to the researchers. Here, a cobalt free cost-effective eutectic high entropy alloy was designed by VEC criterion. The cobalt element in AlCoCrFeNi2.1 alloy is replaced by Fe and Ni in equal proportions to maintain VEC value unchanged. The designed AlCrFe1.5Ni2.6 alloy exhibited a eutectic microstructure composed of FCC (L12) phase and BCC (B2) phase. The room temperature mechanical properties of the designed alloy were comparable to those of AlCoCrFeNi2.1 EHEA and better than those of a majority of as-cast high entropy alloys. An excellent combination of strength and ductility originates from the hetero-interface strengthening and slip continuity across the Kurdjumov-Sachs (K–S) interface. The present work proves the VEC criterion could successfully be used to design the cost-effective eutectic high entropy alloy and the designed alloy has a great potential in engineering applications.

The impact of a Pt-Al bond coat on the high-cycle fatigue (HCF) behaviour of fourth-generation single crystal superalloys at 760℃ and 900℃ was investigated. The Pt-Al bond coat was found to be almost negligible under low stresses at 760℃; however, the bond coat effect was detrimental at 900℃ or under high stresses at 760℃. At 760 °C with increasing high-amplitude stress, the tip cracks preferentially nucleated from defects within coat and propagated inwards, accelerating the fracture. The fatigue life of the coated alloys was considerably decreased at 900 °C, which was attributed to the damage accumulated in the bond coating via oxidation, crack-induced oxide cracking and interfacial microstructure degradation. An Elevated temperature led to the crack-induced oxides shifting from a small fan-shape to a large umbrella-shape, increasing the density of slip bands and quantity of secondary cracks in the substrate. Furthermore, more Ru diffused outwards at 900℃ than that at 760℃, which caused the disappearance of L-C dislocation locks and tertiary γ′ phases and aggravated TCP phases precipitation in the substrate at 900℃. Ultimately, to assess the degradation of the HCF life, an empirical life prediction method was developed, and the calculations results well matched the test results.

Solidification segregation behavior and homogenization heat treatment processes of a difficult-to-deform superalloy for use at 850 °C were studied. Additionally, the effect of carbon content on homogenization, the thermal treatment process, and pore growth behavior within the alloy were discussed. Our results revealed that Al, Ti, and Nb elements are distributed in the interdendritic space, while W and Mo elements are distributed in the dendrite. There is a significant quantity of γ-γ′ eutectic and MC carbide precipitates in the interdendritic space. Notably, for the alloy containing 0.1 wt% C, a homogenization heat treatment at 1200 °C for 48 h can effectively eliminate the segregation and undesirable phases. As carbon content increased, the γ-γ′ eutectic phases diminished, and the homogenization time decreased accordingly. In this context, pores are smaller and more dispersed, which may enhance alloy forging properties.

The increasing penetration of distributed renewable energy and electric vehicles (EV) in local microgrids/residential-community has brought a great challenge to balancing system stability and economic benefits. This paper proposes a decentralized framework based on an efficient federated deep reinforcement learning method for plug-in electric vehicle (PEV) fleet charging management in a residential community, which is equipped with a photovoltaic and battery energy storage system and connected to a local transformer. Firstly, the framework of PEV charging management is described as a virtual EV charging station coordinating charging tasks through sharing public information with distributed agents. Then, an individual preference model of PEV is developed considering heterogenous PEV charging anxiety, battery degradation, and collective penalty. Subsequently, we propose an attention-weighted federated soft-actor-critic method to efficiently seek the co-ordinational scheduling of the PEV fleet charging in a distributed way, where scalability and privacy protection can be ensured with attention-based information sharing. Finally, a real-world case study is conducted to validate the effectiveness and feasibility of the proposed approach.

A novel low-density nickel-based single-crystal superalloy was prepared and the effect of solution treatment on the creep deformation mechanism was systematically investigated. The results reveal that the creep life increases with the increase of solution treatment time, which can be ascribed to microstructural homogenization. However, when the solution treatment time exceeds a threshold limit, the relative proportion of undesirable defects significantly increases, which accelerates the failure and compromises the creep life. The homogenization of the composition leads to the precipitation of a more homogenized γ′ phase and, in turn, results in a more uniform and dense dislocation network, thus hindering the dislocation movement and improving the creep life. The undesirable defects may lead to the stress concentration and weaken the effect of the dislocation network, thus accelerating the creep process and the dislocation are more likely to shear into the γ′ phase. In general, the current study provides guidance for selecting a more reasonable solution treatment time to improve the creep strength.

Ceramic cores are applied in electronics, aerospace, medicine, military, automotive, and other fields. However, the effects of the build direction, along with the shrinkage of the green body and thermal stress, on the mechanical properties of 3D ceramic cores have not been elucidated. To reveal the optimum conditions for crack resistance in a high-solid-loading ceramic core, a silicon-based ceramic core with a solid content of 60 vol% was fabricated through stereolithography 3D printing and analyzed in terms of its microstructure-level crack initiation and propagation. The green bodies were initially 3D printed in different build directions (length-directed, width-directed, and height-directed) and then sintered at different temperatures (1100 °C-1250 °C). Higher sintering temperatures generally produced more cracks, and the synergistic effects of the sintering temperature and build direction induced crack initiation and propagation. The width-directed sample sintered at 1200 °C, in particular, exhibited effectively controlled crack growth without sacrificing strength.

A novel fourth-generation nickel-based single crystal superalloy was brazed with Co-based filler alloy. The effects of post-weld heat treatment (PWHT) on the microstructure and mechanical properties of brazed joints were investigated. The experimental and CALPHAD simulation results show that the non-isothermal solidification zone was composed of M3B2, MB-type boride and MC carbide, and the isothermal solidification zone was composed of γ and γ’ phases. After the PWHT, the distribution of borides and the morphology of the γ’ phase were changed. The change of the γ’ phase was mainly attributed to the effect of borides on the diffusion behavior of Al and Ta atoms. In the process of PWHT, stress concentration leads to the nucleation and growth of grains during recrystallization, thus forming high angle grain boundaries in the joint. The microhardness was slightly increased compared to the joint before PWHT. The relationship between microstructure and microhardness during the PWHT of the joint was discussed. In addition, the tensile strength and stress fracture life of the joints were significantly increased after the PWHT. The reasons for the improved mechanical properties of the joints were analyzed and the fracture mechanism of the joints was elucidated. These research results can provide important guidance for the brazing work of fourth-generation nickel-based single crystal superalloy.

In this work, the effect of the Ru element on the γ′-phase evolution and deformation mechanism in the fourth-generation Ni-based single-crystal superalloy was investigated. Results show that the Ru element alters the distribution coefficient of other elements in the alloy to produce reverse partitioning behavior, which leads to a difference in microstructure between 0Ru and 3Ru. The addition of Ru triggered the incubation period before the beginning of the primary creep stage, which depends on the creep temperature and stress during creep deformation. TEM results revealed that Ru addition inhibits the slip system {111} at medium-temperature (760–1050 °C) and high-stress (270–810 MPa) creep, which brings a considerably low creep rate and high creep life to the Ru-containing alloy.

The relationship between pulsed laser processing parameters and epitaxial growth of alloy is essential to additive manufacturing technology in repairing and manufacturing nickel-based single crystal (SX) superalloys. In this paper, orthogonal experiments of Laser Direct Energy Deposition (DED-L) process have been designed to optimize the process for the epitaxial growth of the SX superalloy. The relationship between process parameters and epitaxial growth of SX superalloy is established in a radar map, which shows that low laser power, pulse width and powder feeding rate help epitaxial growth in the DED-L process. It is implied that increasing the powder feeding rate value in the process range decreases the epitaxial growth rate of the molten pool and increases manufacturing efficiency. The size of the cladding layer width is greatly influenced by laser power (reached 44%) and pulse width (reached 38%). The deposited heigh of the cladding layer is mainly influenced by pulse width (reached 45%) and powder feeding rate (reached 42%). The process parameters have a similar level (approximately 33%) of influence on the powder using efficiency.

IbMYB1 was one of the major anthocyanin biosynthesis regulatory genes that has been identified and utilized in purple-fleshed sweet potato breeding. At least three members of this gene, namely, IbMYB1-1, -2a, and -2b, have been reported. We found that IbMYB1-2a and -2b are not necessary for anthocyanin accumulation in a variety of cultivated species (hexaploid) with purple shoots or purplish rings/spots of flesh. Transcriptomic and quantitative reverse transcription PCR (RT-qPCR) analyses revealed that persistent and vigorous expression of IbMYB1 is essential to maintain the purple color of leaves and storage roots in this type of cultivated species, which did not contain IbMYB1-2 gene members. Compared with IbbHLH2, IbMYB1 is an early response gene of anthocyanin biosynthesis in sweet potato. It cannot exclude the possibility that other MYBs participate in this gene regulation networks. Twenty-two MYB-like genes were identified from 156 MYBs to be highly positively or negatively correlated with the anthocyanin content in leaves or flesh. Even so, the IbMYB1 was most coordinately expressed with anthocyanin biosynthesis genes. Differences in flanking and coding sequences confirm that IbMYB2s, the highest similarity genes of IbMYB1, are not the members of IbMYB1. This phenomenon indicates that there may be more members of IbMYB1 in sweet potato, and the genetic complementation of these members is involved in the regulation of anthocyanin biosynthesis. The 3′ flanking sequence of IbMYB1-1 is homologous to the retrotransposon sequence of TNT1-94. Transposon movement is involved in the formation of multiple members of IbMYB1. This study provides critical insights into the expression patterns of IbMYB1, which are involved in the regulation of anthocyanin biosynthesis in the leaf and storage root. Notably, our study also emphasized the presence of a multiple member of IbMYB1 for genetic improvement.

The effect of the Mo contents of 1.0 wt.%, 1.5 wt.%, 2.0 wt.%, and 3.0 wt.% on the microstructures and mechanical properties of the polycrystalline superalloy with a high W content was studied. The typical dendrite morphology was observed in the high-W superalloy with different Mo contents, containing γ matrix, γ′ phase, eutectic, and MC carbide. After the heat treatment, the primary MC carbides were decomposed into M6C carbides, while a needle-like topologically close-packed (TCP) phase was formed in the alloy with high Mo content, in contrast to the other three alloys with low Mo content. The Mo addition increased the lattice parameter of the γ and γ′ phases and also changed the lattice misfits of the γ and γ′ phase lattice misfits towards a larger negative. The addition of Mo improved the yield strength at room temperature due to the solid solution strengthening and coherency strengthening. The improvement of the stress rupture lives at 975 °C/225 MPa was due to the combination of the suppressed propagation of the microcracks by the carbides and a more negative misfit. When the Mo content reached 3.0 wt.%, the TCP phases formed and decreased the ultimate tensile strength and the stress rupture lives as a result.

Post-bond heat treatment (PBHT) is an effective way to improve the bonding quality of a brazed joint. Herein, brazing of a nickel-based single crystal superalloy is carried out using a Ni-Cr-Co-B-Si-Al-Ti-W-Mo filler alloy, and the microstructure and creep property of the brazed joint are systematically investigated using scanning electron microscopy (SEM), Thermo-Calc software, an electron probe micro-analyzer (EPMA), X-ray diffractometer, confocal scanning laser microscope (CSLM), and transmission electron microscopy (TEM). The results reveal that the as-prepared joint only consists of an isothermally solidified zone (ISZ) and an athermally solidified zone (ASZ), where the cubic γ′ phase is observed in the ISZ, and skeleton-like M3B2, γ + γ′ eutectic and reticular G phases are observed in the ASZ. Furthermore, the γ + γ′ eutectic and G phases disappear and the M3B2 alters from a skeleton-like to block-like shape in the ASZ after PBHT. Meanwhile, some lath-like M3B2 phases are precipitated at the edge of the ISZ and several M3B2 phases are precipitated in the base metal, forming a new zone in the brazed joint, namely at the diffusion affected zone (DAZ). Owing to the removal of low melting point eutectics from the as-prepared joint, the creep life also increases from 188 h to 243 h after PBHT. The current work provides a method for the optimization of brazed joints based on the Ni-based single crystal superalloy.

Chinese hamster ovary (CHO) cell lines are widely used in industry for biological drug production. During cell culture development, considerable effort is invested to understand the factors that greatly impact cell growth, specific productivity and product qualities of the biotherapeutics. While high-throughput omics approaches have been increasingly utilized to reveal cellular mechanisms associated with cell line phenotypes and guide process optimization, comprehensive omics data analysis and management have been a challenge. Here we developed CHOmics, a web-based tool for integrative analysis of CHO cell line omics data that provides an interactive visualization of omics analysis outputs and efficient data management. CHOmics has a built-in comprehensive pipeline for RNA sequencing data processing and multi-layer statistical modules to explore relevant genes or pathways. Moreover, advanced functionalities were provided to enable users to customize their analysis and visualize the output systematically and interactively. The tool was also designed with the flexibility to accommodate other types of omics data and thereby enabling multi-omics comparison and visualization at both gene and pathway levels. Collectively, CHOmics is an integrative platform for data analysis, visualization and management with expectations to promote the broader use of omics in CHO cell research.

The surface morphology and chemical states of W-2%ThO2 thermionic cathode during vacuum high-temperature treatment were investigated in this research. The W-2%ThO2 thermionic cathode was prepared by a solid-liquid doping method combined with high-temperature sintering. The morphology and distribution of thorium oxide were observed using a transmission electron microscope and scanning electron microscope. The chemical states of elements at different temperatures were analyzed by X-ray photoelectron spectroscopy. Results indicate that the surface morphology and chemical form of the alloy evolve with the increase of temperature. The matrix had a lamellar structure at low temperatures, and the surface was relatively flat. The samples were heated to 500 °C, 1100 °C, and 1300 °C for 1 h. During the heating process, thorium oxide changed from granular to spherical, and the matrix was recrystallized. As the heating temperature rises, diffusion channels appear inside the cathode. As the temperature increases, the high-priced tungsten gradually decreases, and the zero-valent tungsten content increases. The adsorbed oxygen left the cathode surface, and the lattice oxygen increased. The surface oxygen content decreased, and the thorium and tungsten content increased.

This paper is concerned with modeling nonequilibrium phenomena in spatial domains with boundaries. The resultant models consist of hyperbolic systems of first-order partial differential equations with boundary conditions (BCs). Taking a linearized moment closure system as an example, we show that the structural stability condition and the uniform Kreiss condition do not automatically guarantee the compatibility of the models with the corresponding classical models. This motivated the generalized Kreiss condition (GKC)—a strengthened version of the uniform Kreiss condition. Under the GKC and the structural stability condition, we show how to derive the reduced BCs for the equilibrium systems as the classical models. For linearized problems, the validity of the reduced BCs can be rigorously verified. Furthermore, we use a simple example to show how thus far developed theory can be used to construct proper BCs for equations modeling nonequilibrium phenomena in spatial domains with boundaries.

Imatinib (IM) resistance could have significant impact on the survival time of the CML-patients treated with IM. Previous studies have shown that the protective effects of the bone marrow stroma cells (BMSCs) on CML cells are achieved by the secretion of CXCL12. The aim of this study was to investigate whether Oroxylin A could reverse the protective effect of BMSCs on CML cells and illuminate the underlying mechanisms. The results showed that CXCL12 could enhance the resistance potential of K562 and KU812 cells to IM by increasing the expression of CXCR4, thus promoting the translocation of β-catenin into nucleus and subsequently increasing the expression of P-gp in K562 and KU812 cells. What's more, IM resistance could also be partially reversed by CXCR4 siRNA transfection. Moreover, the reverse effect of IM resistance by Oroxylin A was demonstrated by the inhibition of β-catenin/P-gp pathway via the decrease of CXCR4 in vitro. The in vivo study also showed that Oroxylin A could decrease the expression of P-gp and β-catenin in mice bone marrow with low toxicity, which could be consistent with the mechanisms verified in vitro studies. In conclusion, all these results showed that Oroxylin A improved the sensitivity of K562 and KU812 cells to IM in BM microenvironment by decreasing the expression of CXCR4 and then inhibiting β-catenin/P-gp pathway.

DZ951G is a novel developed nickel-based directional solidified superalloy with an incipient high melting point and low density. Compared with DZ417G superalloy, DZ951G superalloy has a higher ultimate tensile strength. At intermediate temperatures, the plasticity and strength were both markedly improved, and an obviously anomalous yield behavior could be observed where the yield strength reached its maximum at 760 °C. Below 600 °C, two competitive modes of dislocations shearing γ′ particles existed, in which one was the formation of stacking faults and another was a/2 dislocations shearing. At intermediate temperatures, a transitional phase between shearing γ′ particles and bypassing appeared, and the fracture translated from brittle fracture into ductile fracture. Exceeding 900 °C, bypassing of dislocations was operated under thermal activation. Moreover, short continuous stacking faults still existed at 760 °C. Finally, the various dislocation configurations were rationally illuminated and explained with the intrinsic connection of mechanical properties.

This study concentrates on several factors which govern the nanoscale plasticity of in situ compressed dislocation-free Ni3Al nanocubes: cube size, aspect ratio and the presence of grooves. The yield strength of dislocation-free Ni3Al nanocubes exhibits an apparent size dependence. The size dependence is strong when cubes are smaller than 300 nm. Compared with the strength of bulk Ni3Al single crystals, the strength of nanocubes is two orders of magnitude higher, which clearly demonstrates that there is a size effect. Nanocube plasticity strongly depends on the alignment and the shape of the cubes. Deformed aligned nanocubes either display only a few localized deformation events (slip lines) or were homogenously compressed into flats due to multiple slip dislocation-mediated plasticity. For an aligned cube, crack initiation at the intersection of a slip line with a groove in the cube surface was observed. In case of a double cube, crack initiation occurs at surface irregularities, while subsequent crack propagation occurs along one or more slip planes.

The preparation of rhenium powder by a hydrogen reduction of ammonium perrhenate is the only industrial production method. However, due to the uneven particle size distribution and large particle size of rhenium powder, it is difficult to prepare high-density rhenium ingot. Moreover, the existing process requires a secondary high-temperature reduction and the deoxidization process is complex and requires a high-temperature resistance of the equipment. Attempting to tackle the difficulties, this paper described a novel process to improve the particle size distribution uniformity and reduce the particle size of rhenium powder, aiming to produce a high-density rhenium ingot, and ammonium perrhenate is completely reduced by hydrogen at a low temperature. When the particle size of the rhenium powder was 19.74 µm, the density of the pressed rhenium ingot was 20.106 g/cm3, which was close to the theoretical density of rhenium. In addition, the hydrogen reduction mechanism of ammonium perrhenate was investigated in this paper. The results showed that the disproportionation of ReO3 decreased the rate of the reduction reaction, and the XRD and XPS patterns showed that the increase in the reduction temperature was conducive to increasing the reduction reaction rate and reducing the influence of disproportionation on the reduction process. At the same reduction temperature, reducing the particle sizes of ammonium perrhenate was conducive to increasing the hydrogen reduction rate and reducing the influence of the disproportionation.

Additive manufacturing (AM) of single crystal superalloys has got some progress in recent researches, but there are few reports on eliminating recrystallization or mechanical properties of single crystal superalloys by AM. In this work, single-crystal samples of SRR99 were fabricated at high temperature by laser melting deposition (LMD). Owing to the high temperature of substrate in the deposition process, recrystallization in the following heat treatment process was eliminated. The contrast sample of SRR99 was prepared by directional solidification, and the microstructure evolution during heat treatment and tensile property of deposited samples were analyzed. The results showed that the shapes of the γ ′ phase became irregular after solution treatment in deposited samples. After a solid solution and aging treatment, the γ ′ phase size is larger and the γ ′ volume fraction is slightly lower in deposited samples than in the contrast sample. As a result, the yield and tensile strength of deposited samples are slightly lower than that of contrast samples, but the plasticity of deposited samples is better.

Ammonium perrhenate is widely used in alloy manufacturing, powder processing, the catalytic industry, and other fields. Recrystallization can improve the specific surface area of ammonium perrhenate, reduce its particle size, and improve its particle size distribution uniformity. Therefore, recrystallized ammonium perrhenate can obtain better application benefits in the above fields. Stirring is an important factor that affects the recrystallization of ammonium perrhenate, and this paper systematically analyzes the influence of the stirring paddle types and stirring intensities on ammonium perrhenate during the homogeneous recrystallization process, ultimately revealing the relationship between the growth rate of ammonium perrhenate and the stirring process. Particle image velocimetry physical simulation results showed that the flow field in the reactor was more evenly distributed when using the disc turbine impeller, and a relatively uniform velocity liquid flow area was formed in the whole reactor, while the low-velocity liquid flow area was smaller. Therefore, this information, combined with SEM test results, suggests that under the same recrystallization time and stirring intensity, the stirring effect of a disc turbine impeller is more suitable than a propelling propeller and an Intermig impeller for the recrystallization process of ammonium perrhenate. Moreover, the XRD patterns and SEM analysis showed that if the agglomeration in the systems was too strong or too weak, the growths of the (101) crystal plane and (112) crystal plane were restrained, which caused an attenuation in the growth rates along the crystallographic directions that were orthogonal to the crystal faces. Finally, the reduction experiments show that the recrystallization of ammonium perrhenate could improve the phase parameters of rhenium powders.

The influencing factors of ammonia content and centrifugal speed on ammonium rhenate recovery from waste superalloy were systematically analyzed. It was found that proper ammonia content and centrifugal speed could promote crystal growth and a higher purity of ammonium rhenate was obtained. Moreover, the XRD patterns showed that excessive ammonia content and inappropriate centrifugal speed restrained the growth of (101) crystal plane and (112) crystal plane, which caused the crystal structural regularity and relative crystallinity to attenuate. The microscopic morphology and purity of the crystal also changed.

ABSTRACT Bacterial biofilms are ubiquitous in nature, and their resilience is derived in part from a complex extracellular matrix that can be tailored to meet environmental demands. Although common developmental stages leading to biofilm formation have been described, how the extracellular components are organized to allow three-dimensional biofilm development is not well understood. Here we show that uropathogenic Escherichia coli (UPEC) strains produce a biofilm with a highly ordered and complex extracellular matrix (ECM). We used electron microscopy (EM) techniques to image floating biofilms (pellicles) formed by UPEC. EM revealed intricately constructed substructures within the ECM that encase individual, spatially segregated bacteria with a distinctive morphology. Mutational and biochemical analyses of these biofilms confirmed curli as a major matrix component and revealed important roles for cellulose, flagella, and type 1 pili in pellicle integrity and ECM infrastructure. Collectively, the findings of this study elucidated that UPEC pellicles have a highly organized ultrastructure that varies spatially across the multicellular community. IMPORTANCE Bacteria can form biofilms in diverse niches, including abiotic surfaces, living cells, and at the air-liquid interface of liquid media. Encasing these cellular communities is a self-produced extracellular matrix (ECM) that can be composed of proteins, polysaccharides, and nucleic acids. The ECM protects biofilm bacteria from environmental insults and also makes the dissolution of biofilms very challenging. As a result, formation of biofilms within humans (during infection) or on industrial material (such as water pipes) has detrimental and costly effects. In order to combat bacterial biofilms, a better understanding of components required for biofilm formation and the ECM is required. This study defined the ECM composition and architecture of floating pellicle biofilms formed by Escherichia coli.