Research on industry-spatial relationship of existing industrial zones in Beijiao, Shunde based on comparison of data Point of Interest

Spatial distribution characteristics of existing industrial zones in cities are important to research on their functional upgrading, optimization and transformation. So is the correlation with surrounding functional facilities which providing business supporting and life safeguard. The methods of Kernel Density Estimation, Standard Deviation Ellipse and Spatial Autocorrelation were used in this study, based on comparison of data Point of Interest (POI) of existing industrial zones in Beijiao. The study discussed the changing of characteristics and influence factors of industrial enterprises and surrounding facilities. It made a comparative analysis of the space correlation among the enterprises and facilities, and determined configuration status of facilities. And it provided the optimization strategy which should follow principles of utilization and proper demolition, and a regional centre should be planned. The building density in the area should adjusted in order to restore the ecological environment. A low-carbon and energysaving urban form could to be constructed by optimizing the facility allocation. Tracking industrialspatial dynamics by establishing a transformation database

Research on industry-spatial relationship of existing industrial zones in Beijiao, Shunde based on comparison of data Point of Interest

Spatial distribution characteristics of existing industrial zones in cities are important to research on their functional upgrading, optimization and transformation. So is the correlation with surrounding functional facilities which providing business supporting and life safeguard. The methods of Kernel Density Estimation, Standard Deviation Ellipse and Spatial Autocorrelation were used in this study, based on comparison of data Point of Interest (POI) of existing industrial zones in Beijiao. The study discussed the changing of characteristics and influence factors of industrial enterprises and surrounding facilities. It made a comparative analysis of the space correlation among the enterprises and facilities, and determined configuration status of facilities. And it provided the optimization strategy which should follow principles of utilization and proper demolition, and a regional centre should be planned. The building density in the area should adjusted in order to restore the ecological environment. A low-carbon and energysaving urban form could to be constructed by optimizing the facility allocation. Tracking industrialspatial dynamics by establishing a transformation database.publishedVersio

Phase transition, leakage conduction mechanism evolution and enhanced ferroelectric properties in multiferroic Mn-dopedBiFeO3 thin films

International audiencePure and Mn-doped BiFeO3 thin films wereprepared by a facile chemical solution deposition process.X-ray diffraction patterns and Raman spectra imply a phasetransition from a rhombohedral structure in pure BiFeO3film to a nearly tetragonal structure in Mn-doped BiFeO3films. Moreover, it is found that doping of Mn couldgreatly modify the surface morphology, leakage currentproperties and ferroelectric properties of BiFeO3 films.Consequently, the lowest leakage current density and thelargest remnant polarization are observed in BiFe0.925Mn0.075O3 film which could be well explained by theleakage conduction mechanism and its evolution from thespace-charge-limited current behavior for BiFeO3 andBiFe0.95Mn0.05O3 films to the Poole–Frenkel emission forBiFe0.925Mn0.075O3 film, as well as completely an Ohmicbehavior for BiFe0.90Mn0.10O3 film. Based on the X-rayphotoelectron spectroscopy analysis of Mn ions, we arguethat the varied valences of Mn ions such as Mn4?, Mn3?and Mn2? may play an important role in lowering leakage current density and enhancing the ferroelectric propertiesof BiFeO3 films

Molecular Modelling of Ionic Liquids: Situations When Charge Scaling Seems Insufficient

Charge scaling as an effective solution to the experiment–computation disagreement in molecular modelling of ionic liquids (ILs) could bring the computational results close to the experimental reference for various thermodynamic properties. According to the large-scale benchmark calculations of mass density, solvation, and water-ILs transfer-free energies in our series of papers, the charge-scaling factor of 0.8 serves as a near-optimal option generally applicable to most ILs, although a system-dependent parameter adjustment could be attempted for further improved performance. However, there are situations in which such a charge-scaling treatment would fail. Namely, charge scaling cannot really affect the simulation outcome, or minimally perturbs the results that are still far from the experimental value. In such situations, the vdW radius as an additional adjustable parameter is commonly tuned to minimize the experiment–calculation deviation. In the current work, considering two ILs from the quinuclidinium family, we investigate the impacts of this vdW-scaling treatment on the mass density and the solvation/partition thermodynamics in a fashion similar to our previous charge-scaling works, i.e., scanning the vdW-scaling factor and computing physical properties under these parameter sets. It is observed that the mass density exhibits a linear response to the vdW-scaling factor with slopes close to −1.8 g/mL. By further investigating a set of physiochemically relevant temperatures between 288 K and 348 K, we confirm the robustness of the vdW-scaling treatment in the estimation of bulk properties. The best vdW-scaling parameter for mass density would worsen the computation of solvation/partition thermodynamics, and a marginal decrease in the vdW-scaling factor is considered as an intermediate option balancing the reproductions of bulk properties and solvation thermodynamics. These observations could be understood in a way similar to the charge-scaling situation. i.e., overfitting some properties (e.g., mass density) would degrade the accuracy of the other properties (e.g., solvation free energies). Following this principle, the general guideline for applying this vdW-tuning protocol is by using values between the density-derived choice and the solvation/partition-derived solution. The charge and current vdW scaling treatments cover commonly encountered ILs, completing the protocol for accurate modelling of ILs with fixed-charge force fields