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Thermal stability and the crystallization kinetics of a phase-separated Zr–Cu–Fe–Al bulk metallic glass were investigated using in situ high-energy synchrotron X-ray and neutron diffraction, as well as small-angle synchrotron X-ray scattering. It was revealed that this glass with excellent glass-forming ability possesses a two-step crystallization behavior. The crystalline products and their evolution sequence are more complicated than a homogeneous Zr–Cu–Al glass with average glass-forming ability. The experimental results indicate that a finely distributed nanometer-sized cubic Zr2Cu phase forms first and then transforms to a tetragonal Zr2Cu phase, while the matrix transforms to an orthorhombic Zr3Fe phase. The strength of the Zr–Cu–Fe–Al composite containing cubic Zr2Cu phase and glass matrix increases, and the plasticity also improves compared to the as-cast Zr–Cu–Fe–Al bulk metallic glass. Our results suggest that the formation of multiple and complex crystalline products would be the characteristics of the Zr–Cu–Fe–Al glass with better glass-forming ability. Our study may shed light on the synthesis of bulk-sized glass–nanocrystals composites of high strength and good plasticity.

The multiscale structures in a Pd82Si18 binary bulk metallic glass before and after deformation were studied using electron microscopies, high-energy synchrotron X-ray diffraction, and small-angle scattering techniques. The experimental results revealed an enhancement of hierarchical structure heterogeneities on multiple length scales after deformation. Hierarchical multiple shear bands of high number density were observed after bending, introducing complex but periodically distributed residual strain. Pair distribution function analysis revealed that the connectivity of the short-range clusters on the medium-range scale determines the packing density difference between the tension side and the compression side in the sample after bending. In-situ synchrotron X-ray diffraction study also revealed a transformation of connection modes among short-range clusters under uniaxial tension and compression, which is consistent with those of triaxial tension/compression parts upon bending in Pd82Si18 glassy alloys. The nanoscale heterogeneities for metallic glasses after deformation observed by small-angle scattering and transmission electron microscopy may be attributed to the nanoscale amorphous phase separation and interacting multiple shear bands enhanced by plastic deformation. Our findings suggested that the enhancement of hierarchical heterogeneous structure on multiple length scales may explain the excellent plasticity of Pd-Si glassy alloys, deepening the understanding of structure-property relation during plastic deformation in metallic glasses.

In-situ synchrotron high-energy X-ray diffraction was used to study the kinetics of structure evolution for two Fe-based bulk metallic glasses with different thermophysical behaviors upon heating and isothermal annealing in the supercooled liquid region. It is found that the structure change of (Fe0.72B0.24Nb0.04)97Y3, an average glass former, follows a continuous disordering process before crystallization, while that of (Fe0.72B0.24Nb0.04)95.5Y4.5, a better glass former with an anomalous exothermic peak below the crystallization temperature, is characterized by a reentrant supercooled liquid behavior. A hidden amorphous phase with a configurationally highly-correlated structure is found at a critical temperature of the anomalous exothermic peak for the (Fe0.72B0.24Nb0.04)95.5Y4.5 supercooled liquid, and then it reenters the disordered phase of lower correlation length at a higher temperature. Synchrotron diffraction and the density measurements together illustrate that the liquid-liquid phase transition accompanies with an unusual density change upon isothermal annealing at the anomalous exothermic peak temperature. Our experimental results suggest that a liquid-liquid phase transition which occurred at the medium-range length scale plays an important role in stabilizing the (Fe0.72B0.24Nb0.04)95.5Y4.5 supercooled liquid. Possible mechanisms for the observed differences and the relationship with the glass-forming ability are discussed based on the results of the pair distribution function analysis.

The systolic and diastolic dyssynchrony is physiologically related, but measure different left ventricular mechanisms. Left ventricular systolic mechanical dyssynchrony (systolic LVMD) has shown significant clinical values in improving cardiac resynchronization therapy (CRT) response in the heart failure patients with dilated cardiomyopathy (DCM). Our recent study demonstrated that LV diastolic dyssynchrony (diastolic LVMD) parameters have important prognostic values for DCM patients. However, there are a limited number of studies about the clinical value of diastolic LVMD for CRT. This study aims to explore the predictive values of both systolic LVMD and diastolic LVMD for CRT in DCM patients. Eighty-four consecutive CRT patients with both DCM and complete left bundle branch block (CLBBB) who received gated resting SPECT MPI at baseline were included in the present study. The phase analysis technique was applied on resting gated short-axis SPECT MPI images to measure systolic LVMD and diastolic LVMD, characterized by phase standard deviation (PSD) and phase histogram bandwidth (PBW). CRT response was defined as ≥ 5% improvement of LVEF at 6-month follow-up. Variables with P < 0.10 in the univariate analysis were included in the multivariate cox analysis. During the follow-up period, 59.5% (50 of 84) patients were CRT responders. The univariate cox regression analysis showed that at baseline QRS duration, non-sustained ventricular tachycardia (NS-VT), systolic PSD, systolic PBW, diastolic PSD, diastolic PBW, scar burden and LV lead in the scarred myocardium were statistically significantly associated with CRT response. The multivariate cox regression analysis showed that QRS duration, NS-VT, systolic PSD, systolic PBW, diastolic PSD, and diastolic PBW were independent predictive factors for CRT response. Furthermore, the rate of CRT response was 94.4% (17 of 18) in patients whose LV lead was in the segments with both the first three late contraction and the first three late relaxation; by contrast, the rate of CRT response was only 6.7% (1 of 15, P < 0.000) in patients whose LV lead was in the segments with neither the first three late contraction nor the first three late relaxation. Both systolic LVMD and diastolic LVMD from gated SPECT MPI have important predictive values for CRT response in DCM patients. Pacing at LV segments with both late contraction and late relaxation has potential to increase the CRT response.

The multiscale structures in a Pd82Si18 binary bulk metallic glass before and after bending were studied using electron microscopy, high-energy synchrotron X-ray diffraction, and small-angle X-ray scattering. The experimental results revealed the enhancement of hierarchical structure heterogeneities on multiple length scales after deformation. Hierarchical multiple shear bands of high number density can be observed after bending, introducing complex but periodically distributed residual strain. Pair distribution function analysis revealed that the connectivity of the short-range cluster on the medium-range scale determines the packing density difference between the tension side and the compression side in the sample after bending. The electron density fluctuations on the nanoscale observed in the deformed part of the sample are indicative of a nanoscale amorphous phase separation induced by plastic deformation. Our findings will deepen the understanding of the plastic deformation mechanism of metallic glasses and shed light on designing glassy alloys of excellent plasticity and toughness through hierarchical multiscale structure heterogeneities.

The effects of casting currents on the thermophysical behaviors, atomic and nanoscale structure, and mechanical properties of two Zr-based-bulk metallic glasses, i.e., Zr59Cu33Al8 and Zr59(Cu0.55Fe0.45)33Al8, were studied by using differential scanning calorimetry, wide-angle X-ray diffraction, and small-angle X-ray scattering, as well as compression tests. The casting currents can be tuned to change the casting initiative temperature. Results revealed that there is no anomalous structural change for the Zr59Cu33Al8 molten liquid before crystallization during cooling with different casting currents. In contrast, liquid-state phase separation was suggested to occur in the Zr59(Cu0.55Fe0.45)33Al8 molten liquid prepared using lower casting current before crystallization during cooling. The position shift of the first sharp diffraction peak for the diffraction pattern of Zr59(Cu0.55Fe0.45)33Al8 shows that the density of the molten liquid may decrease upon cooling at different casting currents. The small-angle X-ray scattering results indicate that the heterogeneity of the Zr59(Cu0.55Fe0.45)33Al8 metallic glasses increases with decreasing the casting temperature. As a result, the metallic glasses with a liquid-state phase separation possess better mechanical properties, including higher-yielding stress and more significant compressive ductility. The increase in degree of heterogeneity formed by nanoscale liquid-state phase separation and their interactions with the shear bands for the Zr–Cu–Fe–Al bulk metallic glasses were suggested to be responsible for the enhanced mechanical properties.

The presence of a liquid–liquid phase transition in the supercooled-liquid temperature range for a glass-forming Zr–Cu–Al–Ag alloy has been revealed using a suite of in situ neutron scattering techniques, including small-angle neutron scattering (SANS) and total neutron scattering. The SANS data analysis is indicative of the enhancement of nanoscale structural heterogeneities prior to crystallization, which is further supported by the total scattering result that points to an increase in the degree of medium-range ordering during the transition. In addition, a calorimetric anomaly and abnormal thermal expansion behavior were also observed upon heating. As such, this study provides multiscale structural evidence on the liquid–liquid phase transition and helps to gain insight into its underlying mechanism in terms of cluster connectivity.

The pathway of amorphous-to-crystalline phase transformation in Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glasses was studied using a suite of in-situ techniques. Multi-scale structure evidence reveals a five-stage pathway, analogous to the non-equilibrium transformation process with Guinier-Preston zones during aging in precipitation-hardened alloys, by the following sequence upon isothermal annealing the alloy in the supercooled liquid region: polyamorphous phase transition, chemical phase separation, the formation of a poorly-ordered metastable phase, and the formation of a final crystalline product. The changeable incubation periods at different annealing temperatures, and the abrupt multi-scale structure changes, as well as a latent heat release in the calorimetric measurements, support the first-order nature of the phase transformation at early stages. The structure evolution in real-space indicates that the enhancement of cluster connectivity on the medium-range scale plays essential roles in the early stages of the phase transformation, while the interface-limited ordering dominates the later stages. The experimental results suggest the phase transformation pathway with “Guinier-Preston zone-like” precipitates accompanied by the kinematic development of core-shell structures of diffuse interfaces with order parameters gradients, enabling the step-by-step decrease of free energy of the alloy system during phase transformation, which might be a characteristic behavior for multicomponent Zr-based alloys with excellent glass-forming ability.

This paper establishes hedonic price model and uses statistical methods such as multiple regression to analyze educational resources spillover effects on housing prices. It analyzes different market segments using the 3597 samples of school district housing on Xuhui District. The result shows that the overflow prices of Schools quality and Distance to schools reach 219 yuan and 2,844 yuan, respectively. And the influence of school characteristics on housing prices is also different in different market segments. Finally, combined with the demand of school district housing unit and area, it makes some appropriate recommendations to the education department, urban planning department, developers and consumers.

Housing security is a major social problem which related to the national economy, during the implementation of affordable housing projects, because of the obvious game relationships between stakeholders, which includes the central government, local government, developer and the low-income group, in their game relationships, each will demonstrate its "economic man" characteristics. This topic provides a theoretical analysis of the objective phenomenon by the use of the theory of stakeholders and game theory, which aims at the problems and disadvantages during the implementation of affordable housing. By making use of the game theory, analyzing the game relationships between stakeholders of affordable housing, exploring the origin reasons of the inefficiency of the affordable housing policy, proclaiming the problems between the stakeholders in the game, meanwhile, based on the game theory analysis, give the optimization ways and advices upon stakeholders and the affordable housing policy.