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This paper studies the effects of a high magnetic field on the structural evolution and magnetic properties of nanocrystalline films prepared on quartz substrates by a molecular beam vapor deposition (MBVD) method. Atomic force microscope, X-ray diffractometer, transmission electron microscope and vibrating sample magnetometer were used to study the microstructures and magnetic properties of the films. The results indicate that high magnetic field has no obvious influence on crystal structures except changing the lattice constant of the films. However, the high magnetic field can refine particle size. The film deposited under magnetic field tends to grow through columnar mode because of the magnetized particles aligning along the direction of magnetic field. Furthermore, the ordered and dense arrangement of atoms results in more spins contained in per unit volume and improves the saturation magnetization (Ms). Ms of the 6 T film increases by 70% (578 emu/cm3) than that of the film without magnetic field (341 emu/cm3), and the coercivity is also slightly increased for the 6 T film. Nanocrystalline magnetic Ni films were prepared under high magnetic field. It is found that a high magnetic field changes the growth mode and increases the saturation magnetization of Ni film. The high magnetic field also improves the ordered and dense arrangement of Ni atoms. [ABSTRACT FROM AUTHOR]

Al-Ni hypereutectic alloys with various compositions were solidified under various magnetic field conditions to investigate the alignment of primary Al3Ni phases. The results showed that the application of high magnetic fields could improve the homogeneity of the primary Al3Ni phase distribution and induce the alignment of primary Al3Ni phases in the direction perpendicular to the magnetic field direction to form chain-like structures. However, the alignment was different from the orientation of the Al3Ni phases. Furthermore, the degree of the alignment decreased with the increasing concentration of Ni element. This can be attributed to the combination effects of high magnetic field and alloy composition on the concentration field around the crystallized primary Al3Ni crystals. [ABSTRACT FROM AUTHOR]

Mn-90.4wt% Sb alloy specimens were solidified under both uniform magnetic field and magnetic field gradient conditions. The solidification behavior was examined to elucidate the effects of high magnetic fields on the solidified structure evolution of this hypoeutectic alloy. The macrostructures on the longitudinal section of the alloys were investigated by optical microscopy and x-ray diffraction (XRD). The volume fraction of primary MnSb phases and the interrod spacing of the eutectic were measured by metallographic analysis. It was found that the segregation of the primary MnSb particles at the certain regions of the specimens occurred under the influence of high magnetic field gradients. The MnSb phases obtained under magnetic fields were oriented with their (h0 l) planes along the direction of the magnetic field. Both the volume fraction of primary MnSb phases and the interrod spacing of the eutectic were decreased upon the application of the high magnetic fields. [ABSTRACT FROM AUTHOR]

The 2009 seminar on China and Medieval World History was held from August 23 to 26, 2009, at Chunmin Island, Shanghai, China. This seminar was sponsored by the Chinese Society of Medieval World History and Shanghai Normal University. Over 120 scholars and researchers from forty-plus universities and research institutes attended the seminar and presented more than sixty research papers. The themes of this seminar were as follows: 1) the political systems of medieval states; 2) the medieval economics and social transition; and 3) medieval culture.

An investigation on oscillating characteristic of free surface in a liquid bridge for high Pr number fluids under gravity has been conducted numerically. Against the former studies, free surface is treated as a deformable surface in the direct numerical simulation (DNS) of liquid bridge by using a mass conserving level set method for the first time. The results show that, the moving track of vortex centers appears the shape of axisymmetric hook in the stable stage of thermocapillary convection, and the fluctuation of surface velocity is closely relative to the motion of cell flow toward the center and cold disk. In the process of transforming from the stable stage to oscillatory stage, the moving track of vortex centers of cell flow shows the asymmetry and step characteristic. The coupling effects of the temperature, velocity and free surface oscillations constitute complete mechanism of thermocapillary convection oscillations. The temperature firstly oscillates at the hot corner, and transfer direction of temperature oscillation is from the hot corner to inner. The velocity of surface flow is larger than that of internal flow, and the surface flow is supplied by the bulk return flow with the disturbance information of the velocity. The velocity oscillation lags behind the temperature oscillation at the hot corner. The closer to the intermediate height, the larger amplitudes of temperature and velocity are. The oscillation law of velocity and free surface at the intermediate height are the same, and there are two obvious oscillation bifurcations. [ABSTRACT FROM AUTHOR]

[Display omitted] Segmenting casting defect regions is vital for assessing defect levels in casting products. In complex backgrounds with multi-scale defects and regions of fuzzy and weak texture, existing methods often fail to capture detailed features of the defect, leading to incomplete segmentation. This study developed a casting defect region segmentation method based on a dual–channel encoding–fusion decoding (DCE–FD) network. Initially, an encoding network module based on a deep and shallow dual–channel structure (ENM–DSDCS) was established to extract macroscopic and multi-scale detail features using deep and shallow structure networks, respectively. This approach ensures comprehensive feature extraction from multi-scale fuzzy and weak texture defect areas. Further, a decoding network module based on attention-based bidirectional guidance fusion (DNM–ABGF) was developed. This module guides the semantic and multi-scale detail branch features to achieve complementary information fusion at each scale level during the decoding stage, thereby preserving fuzzy boundaries and other details in the fusion process and enhancing the accuracy and integrity of segmentation. Experimental results demonstrate that the mean intersection over union (mIOU) and Dice coefficients for defect region segmentation in radiographic images of castings were 92% and 75.71%, respectively. These metrics surpass those of eight advanced segmentation methods in terms of accuracy and consistency. The proposed method significantly improves sensitivity to feature detail and accurately segments potential fuzzy regions of multi-scale defects, offering promising advancements in the nondestructive testing of casting products. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration (IDD) is considered the basis of serious clinical symptoms, especially for low back pain (LBP). Therefore, it is essential to explore the regulatory role and diagnostic performance of dysregulated genes and potential drugs in IDD. Through WGCNA co-expression analysis, 36 co-expression modules were obtained. Among them, MidnightBlue and Red modules were the most related to IDD. Functional enrichment analysis showed that the Red module was mainly related to neutrophil activation and regulation of cytokine-mediated signaling pathway and apoptosis, whereas the MidnightBlue module was mainly related to extracellular matrix organization, bone development, extracellular matrix, extracellular matrix component, and other extracellular matrices. Furthermore, 356 genes highly related to the module were screened to construct a protein interaction network. Network degree distribution analysis showed that the known IDD-related genes had a higher degree of distribution. Enrichment analysis demonstrated that these genes were enriched in MAPK_SIGNALING_PATHWAY (FDR = 0.012), CHEMOKINE_SIGNALING_PATHWAY, and some other pathways. By constructing a disease-gene interaction network, three disease-specific genes were finally identified. Through combining with the drug-target gene interaction network, two potential therapeutic drugs, entrectinib and larotrectinib, were determined. Finally, based on these genes, the diagnostic model in the training dataset, test dataset, and verification dataset all showed a high diagnostic performance. The findings of this study contributed to the diagnosis of IDD and personalized treatment of IDD. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a rigorous proof of existence and uniqueness of solutions to laminar boundary layer flow in power law non-Newtonian fluid. A theoretical estimate for skin friction coefficient is given, which is characterized by a power law exponent. The reliability and efficiency of the proposed estimate formula are verified by numerical results with a good agreement. The estimate formula can be successfully applied to give the value of the skin friction coefficient. [Copyright &y& Elsevier]

Suitable similarity transformations were used for reducing the generalized N-diffusion equations to a class of singular nonlinear boundary value problems. Similarity solutions are presented analytically and numerically. The results indicated that for each fixed α, the general diffusion flux θ(s) decreases with the increase of the power law N and sharply with the increase of σ. For 0<σ&les;1, θ(s) decrease with the increase of α, however, the behavior is quite opposite for σ>1. [Copyright &y& Elsevier]

The effects of Co, Ni together with W addition on the precipitation sequence, amount, and composition of carbides and FCC matrix in Fe–C–V–Cr–Mo based alloys are investigated with the help of Partial Equilibrium (PE) approximation and thermodynamic calculations as well as differential scanning calorimetry (DSC) and electron backscatter diffraction (EBSD) ‐ energy dispersive spectrometer (EDS) analyses. Results show that, individually, Co and Ni elements strengthen the matrix by their great solubility in FCC matrix; W element enlarges the hardness of the alloy through benefiting the formation of M6C carbide. Mutually, the addition of Co and Ni together with W increases the precipitation temperature of the eutectic carbides, although the addition of Co and Ni itself exerts little influence on the nature (type, amount, and composition) of the carbides. These predictions combined with the experimental verifications provide potentials for the alloy design and the property control in high speed steels. [ABSTRACT FROM AUTHOR]

Sinter-HIP combining vacuum and pressure in one-step sintering process has been applied to prepare ultrafine crystalline cemented carbide with a surface gradient layer enriched in binder. The effect of powder particle size on gradient formation and grain growth has been examined. The results show that the gradient layer thickness increases with decreasing WC and Ti(C,N) powder particle size. The number of abnormal WC grains increases with decreasing WC powder particle size. The formational mechanism of the gradient cemented carbide with ultrafine grains is discussed through analyzing the decomposability of nanoscale Ti(C,N), atomic diffusion and grain growth during one-step Sinter-HIP process. [ABSTRACT FROM AUTHOR]

Ultrafine crystalline functionally graded cemented carbides (FGCCs) with a surface zone enriched in binder phase were prepared by a one-step Sinter-HIP method. The influence of sintering pressure and cubic carbide composition on the formation of gradient layer was examined. The results show that the ultrafine FGCC with surface zone enriched in binder phase can be formed by the one-step Sinter-HIP method. The process of the gradient layer formation is accelerated under higher sintering pressure; the gradient layer thickness increases with the sintering pressure increasing. The gradient layer thickness is controlled by diffusion distance of cubic carbide formers, such as Ti, Ta and Nb. The addition of (Ta,Nb)C leads to decrease the thickness of gradient layer. [ABSTRACT FROM AUTHOR]

This paper studies the effects of Ag atomic segregation from the inner (100) or (111) planes on the melting of Ag-Pd clusters with different sizes by a molecular dynamics simulation. The results show that Ag segregation leads to the atomic energy decreases with increasing the temperature. Furthermore, the effect of the (100) segregation is larger than that of the (111) segregation. Meanwhile, the influence of segregation on the energy decreases with increasing the cluster size. The melting points of the clusters without segregation are the largest, followed by the clusters with a (111) and (100) segregation. [ABSTRACT FROM AUTHOR]

Structural evolutions of Co 561 clusters supported on the Cu(010) substrate were studied by molecular dynamics simulation using an embedded atom method. Energy, snapshot, pair distribution function and epitaxial factor were used to analyze the effects of supported position, configuration and temperature on the structural evolutions. It is found that the energy of the cluster changes significantly with varying the supported position and the original configuration. The most stable supported position is (111) facet. As a function of configuration the stability decreases in the order: icosahedron > truncated octahedron > decahedron > cuboctahedron > sphere. Supported (111) facet changes to stack along the (100) of substrate. Epitaxial growth on the substrate occurs for all configurations. The epitaxial temperature and the amount of epitaxial atoms are related to the configuration. The epitaxial growth is adverse to the stability of the cluster, while the epitaxy has no effect on the crystal structure of the supported cluster. The energy of the cluster is reduced by the epitaxial growth and atomic penetration into the substrate but is enhanced by the distortion of the cluster on the substrate. [ABSTRACT FROM AUTHOR]

In this study we have explored how a high magnetic field (HMF) affects the structure and magnetic properties of Fe thin films fabricated on Si (100) substrates at various substrate temperatures by using a thermal evaporation method. At a substrate temperature of room temperature (RT), the HMF increased the width of column and the formation energy of the films. This behavior occurred because the HMF induced an excess energy-Zeeman energy which is larger than the sum of the kinetic energy and thermal energy of Fe without the HMF. This increased the particle size and decreased the roughness of the film deposited at RT and 6 T. When the substrate temperature was increased to 400 °C, the growth mode is changed from columnar (RT) to layered (400 °C). The HMF increased the grain size. The film deposited at RT and 6 T had much improved soft magnetic properties from its modified microstructure. While thermal disturbances decreased the effect of HMF on the magnetic properties of the film deposited at 400 °C. In particular, the influence of HMF on the microstructure and magnetic properties of Fe films is significant not in the evaporation stage but in the condensation process of film. [ABSTRACT FROM AUTHOR]

Nanocrystalline Fe 30 Ni 70 (in atomic %) thin films were prepared by molecular-beam-vapor deposition in magnetic fields with different magnetic flux densities. The microstructure evolution of these thin films was studied by atomic force microscopy, transmission electron microscopy, and high resolution transmission electron microscopy; the soft magnetic properties were examined by vibrating sample magnetometer at room temperature. The results show that all our Fe 30 Ni 70 thin films feature an fcc single-phase structure. With increasing magnetic flux density, surface roughness, average particle size and grain size of the thin films decreased, and the short-range ordered clusters (embryos) of thin films increased. Additionally, the magnetic anisotropy in the in-plane and the coercive forces of the thin films gradually reduced with increasing magnetic flux density. [ABSTRACT FROM AUTHOR]

The effects of high magnetic field annealing on the inter-diffusion behavior of Co/Si (100) films were investigated using diffusion couple technique. Significant Co and Si inter-diffusion was verified by X-ray photoelectron spectroscopy. The inter-diffusion coefficients of thin-film/semiconductor were calculated. Compared to the no-field case, the inter-diffusion coefficients clearly increased when a high magnetic field of 11.5 T was applied at 300 °C, 350 °C, 450 °C and 500 °C. This effect can be attributed to an increase in the chemical potential gradient induced by magnetic free energy in a high magnetic field. For the samples at 400 °C, the inter-diffusion coefficients decreased when a high magnetic field of 11.5 T was applied. The phenomenon may due to the structure transformation caused by a high magnetic field. [ABSTRACT FROM AUTHOR]

The Fe 60 Ni 40 (in atomic %) nanoparticles (NPs) thin films with 90 nm thickness were prepared on 25 and 400 °C quartz substrates by using the molecular beam vapor deposition (MBVD) method under a 6 T high magnetic field (HMF). The effects of a HMF on the structure evolution and properties of Fe–Ni thin films were studied by using X-ray diffraction, atomic force microscopy, transmission electron microscopy, vibrating sample magnetometer and four-point probe method. The results show that the crystallinity of thin films is enhanced by a 6 T HMF, and a 6 T HMF changes phase composition of thin films on 25 °C substrate. It is found that the nanoparticle size decreases; the nanoparticle size distribution becomes narrow, and the root mean square (rms) roughness of thin films decreases under a 6 T HMF relative to that without HMF. These lead to the decrease of coercive force, and the increase of in-plane remanence ratio under a 6 T HMF. [ABSTRACT FROM AUTHOR]

Abstract: The effect of a high magnetic field on phase formation and determination in Ni–Fe film at nanoscale is reported. The bcc structure of the film changed to the coexistence of bcc and fcc phases by increasing the substrate temperature from 25 to 200 to 400 °C without magnetic field. Under a 6 T magnetic field, a coexistence of bcc and fcc phases was formed whatever structures the films prepared without magnetic field are. Furthermore, each nanograin exhibited only a single phase. The effect of high magnetic field indicates that the reduction in the Gibbs free energy (entropy) for the fcc phase by the high magnetic field is larger than that for the bcc phase. Furthermore, the reduction is different for various substrate temperatures. The results indicate that the phase formation is tunable at the nanoscale under high magnetic field. [Copyright &y& Elsevier]

Abstract: We report on the influence of magnetic field strength on the alloy Tb0.27Dy0.73Fe1.95 during slow-cooling solidification. We examined the effect of magnetic field strength on microstructure, magnetization, and magnetostrictive properties of this giant magnetostrictive alloy. We found that after field-treated solidification, the microstructure of specimens had a distinct grain arrangement and displayed magnetic anisotropy. The crystal orientation changed from random in the field-free treatment to aligned along the 〈110〉 direction in flux densities of 1 and 2.2T, and along the easy magnetization axis 〈111〉 at a flux density of 4.4T. In consequence, the magnetostrictive coefficient of the samples under various stresses improved with increasing magnetic flux density. Both the d 33 and k 33 values and the energy transformation efficiency of the field-treated specimens showed strong enhancements. [Copyright &y& Elsevier]

Highlights: [•] We present the change of the crystal orientation and magnetostriction of TbFe2 based alloy during treatment in the semi-solid state in high magnetic fields. [•] Orientation of the TbFe2 phase undergoes a transformation of 〈113〉 to 〈111〉 to 〈110〉 with increasing magnetic flux density. [•] Magnetostrictive property is slightly lowered at 4.4T, but strongly enhanced at 8.8T and 11.5T. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline Fe x Ni1−x (in at%, x=0.74, 0.6, 0.55, and 0.3) thin films were prepared on a 25°C quartz substrate by using a molecular beam vapor deposition method with and without a 6T magnetic field. The microstructure of the thin films was characterized by energy dispersive x-ray spectroscopy, x-ray diffractometry and transmission electron microscopy. The magnetic and electrical properties of the thin films were examined by a vibrating sample magnetometer and four-point probe method. Results show that the thicknesses of these films with different compositions are 50, 90, 80, and 150nm, correspondingly. The crystallinity of Fe x Ni1−x (x=0.74 and 0.6) thin films is enhanced, and the γ 〈111〉 orientation degree of the Fe x Ni1−x (x=0.55 and 0.3) thin films increases under a 6T magnetic field. The grain refinement and defect decrease under 6T magnetic field are affirmed by TEM. A 6T magnetic field can help the thin films transform from anisotropy to isotropy. The soft magnetic properties of the Fe x Ni1−x (x=0.74, 0.6, 0.55, and 0.3) thin films are enhanced, and their resistivities decrease under a 6T magnetic field. [Copyright &y& Elsevier]

This paper studies the melting of Ag-Pd bimetallic clusters with different Ag concentrations and atomic distributions by using molecular dynamics simulation with a general embedded-atom method. The melting of a cluster with 45 % Ag atoms distributing in the core was compared with that of 45 %, 15 % Ag on the surface and 15 % Ag in the core. It is found that the energy variation with the increasing temperature is strongly related to the Ag atomic segregation, due to the reason that there is a competition between the decreased energy induced by the atomic segregation and the increased energy as the temperature increases. The melting of the Ag-core clusters with different Ag concentrations from 5 to 55 % Ag was further explored. It is found that the irregular variation of energy occurred that the atomic energy increases, keeps unchanged or decreases with the increase of the temperature. Furthermore, the irregular phenomena of the melting were induced by the Ag concentrations. This gives a new method to tune the melting in bimetallic clusters. [ABSTRACT FROM AUTHOR]

The effects of an 11.5 T high magnetic field on the growth behavior of compounds layers during reactive diffusion in solid Al/solid Mg diffusion couples have been investigated. After annealing with and without a magnetic field, the interfacial zone was still composed of two layers of stable compounds β (MgAl) and γ (MgAl), but the thicknesses of the layers were increased by the magnetic field. Data analysis of the thicknesses of compound layers showed that the growth of the γ layer was controlled by grain boundary diffusion as well as volume diffusion at B=0 T, but only controlled by volume diffusion when an 11.5 T high magnetic field was applied. The interdiffusion coefficients for the samples annealed at 643-693 K were calculated from the parabolic relationship between the migration of the interface and the annealing time. The results show that the diffusion constant increased due to the high magnetic field, increasing the chemical potential gradient, and in turn it caused the interdiffusion coefficient to increase. [ABSTRACT FROM AUTHOR]

Abstract: In this work, Mn–Sb alloys were melted and held in various magnetic field gradients for various times. The corresponding distributions of the alloying elements in the alloys in liquid state were revealed by a quenching method. It was found that the primary MnSb showed a relatively uniform distribution in the alloy quenched in the magnetic field gradient of B dB/dz=0T2/m, while it was mainly distributed in the lower and upper part of the alloys quenched in negative and positive magnetic field gradients, respectively. The experimental results show that it is possible to in situ control the distributions of alloying elements in alloys in the liquid state using high gradient magnetic fields if there is a difference in magnetic susceptibility. [Copyright &y& Elsevier]

Abstract: The effect of high magnetic fields on the nucleation behavior of Ni-90at%Cu alloys and pure Sb were investigated. It was found that the undercooling of both Ni-90at%Cu alloys and pure Sb before nucleation was increased by the application of a high magnetic field of 11.5T. An obvious grain refinement was observed in the Ni-90at%Cu alloys solidified in the high magnetic field. Such grain refinement could be linked to the increase of the undercooling. The increase in the undercooling in the high magnetic field was attributed to the suppressing effect of the Lorentz force on the convection in the melt. Such suppressing effect could delay the formation of oxides which were responsible for the heterogeneous nucleation of the materials. [Copyright &y& Elsevier]

Abstract: The thermal instability of the Fe fibers in the heavily deformed Cu–12.8wt.%Fe composites is investigated experimentally and numerically. The fiber evolution is characterized by a field emission scanning electron microscopy (FESEM). The results show that the dominant instability of the Fe fibers is the longitudinal boundary splitting which is determined by the greater cross sectional aspect ratio (width/thickness, w/t) and the larger ratio of boundary to interfacial energy (γ B/γ S). The longitudinal boundary splitting makes the ribbon-like Fe fibers evolve into a series of cylindrical fibers. Then the cylindrical Fe fibers undergo the instability process in terms of the breakup, growth and coarsening concurrently. The breakup times are accurately predicted by the Rayleigh perturbation model. The growth process primarily contributes to the higher increasing rate of the fiber radius during isothermal annealing at 700°C than that calculated by the coarsening theory developed for cylindrical fibers, since the Cu-matrix of composites is highly supersaturated after casting/cold-working process. [Copyright &y& Elsevier]

Abstract: With the imposition of a high magnetic field up to 11.5T, the morphologic transition of the MnBi phase and the magnetic properties of the Bi–4.36wt.% and 8.25wt.% Mn alloy specimens solidified from a semi-solid state were investigated. Compared with the irregular shape and unequal dimensions of MnBi grains under 0T, the coarsened MnBi grains were connected together and tended to be parallel to the direction of the external field of 11.5T. The changes might be attributed to the Ostwald ripening of ferromagnetic grains in the isothermal holding stage and subsequent aggregation along the direction of external field driven by mutual magnetic force among the grains. The uniform orientation of the ferromagnetic MnBi grains obtained in the microstructures effectively improves the saturation magnetization of the Bi/MnBi composite materials, but the oversized grains and the defects in grains make the coercivity decrease. [ABSTRACT FROM AUTHOR]