Color-tunable hypersensitive temperature sensor based on metal organic framework doped with Eu^(3+)and Dy^(3+)via phonon-assisted energy transfer

In this work,catena-[(μ-benzene-1,3,5-tricarboxylato)-(1,10-phenanthroline)-(N,N-dimethylfo rmamide)-gadolinium(ⅲ)-N,N-dimethylformamide solvate](denoted as Gd-MOF)co-doped with Eu^(3+)and Dy^(3+)was successfully synthesized.The entire X-ray diffraction peaks of the sample match well with the GdMOF phase.A detailed characterization by inductively coupled plasma mass spectrometry(ICP-MS)shows that the actual concentration is basically consistent with the design concentration.The temperature sensing properties of Gd-MOF:Eu^(3+),Dy^(3+)were analyzed by temperature-dependent fluorescence spectra from 213 to 453 K.As temperature rises,the emission color of Gd-MOF:Eu^(3+),Dy^(3+)changes from yellow to red.The relative sensitivity reaches a maximum of 5.87%/K at 383 K in the Gd-MOF:1%Eu^(3+),30%Dy^(3+)sample.The high relative sensitivity of this MOF is due to the phonon-assisted energy transfer from Dy^(3+)to Eu^(3+),which is proved via fluorescence decay curves and fluoresce nce spectra.The major route of this energy transfer is^(4)F_(9/2)(Dy^(3+))→^(5)D_(1)(Eu^(3+)).

Spatial characteristics of defensive traditional architecture in multiethnic village of Guangxi:Case studies of Mozhuang Village and Guxietun Village

Defensive traditional architecture research is critical to the understanding of the ethnic history and multiethnic villages.Currently,there are few studies on the combination of traditional architecture and multiethnicity,and most of the defensive traditional buildings in multiethnic villages of Guangxi are facing the plight of being destroyed and abandoned.The aim of this research is to identify the spatial characteristics,commonalities,and differences of Guangxi’s defensive traditional architecture with Mozhuang Village and Guxietun Village as the examples,in order to preserve the architectural and ethnic components of these villages.This research uses the four research methods:literature review,field research,observation and space syntax analysis,and it summarizes the three results from the five aspects:plan,elevation,construction material,masonry and decoration.Results showed that the spatial characteristics are dominated by the ethnic group with the higher technological,cultural or economic level,and there are both commonalities and differences in defensive traditional architecture in multiethnic villages.Based on the three study results,this research proposes some overall suggestions toward traditional villages and architecture improvement in ethnic areas.