The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-X...The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved scale.This combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme conditions.Moreover,ED-XAS and SR-IR can be used independently in the two branches of the D-Line.The ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample position.An exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy resolution.The focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 keV.Using one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be realized.Several distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.展开更多
Europium and samarium co-doped strontium sulfide (SrS∶Eu, Sm) infrared up-conversion phosphor was synthesized through calcining the precursor, which prepared by wet-method with strontium carbonate (SrCO_3), sulphur (...Europium and samarium co-doped strontium sulfide (SrS∶Eu, Sm) infrared up-conversion phosphor was synthesized through calcining the precursor, which prepared by wet-method with strontium carbonate (SrCO_3), sulphur (S), europium oxide (Eu_2O_3) and samarium oxide (Sm_2O_3) as the starting materials, lithium fluoride (LiF) as the fluxing agent, at 750~1200 ℃ in carbon-reducing atmosphere. XRD analysis shows that SrS crystal structure is formed at 750 ℃, most completely at 1100 ℃. The IR up-conversion luminescence properties were characterized by excitation, emission, up-conversion excitation, up-conversion emission and thermoluminescence spectra. The spectral analysis associated with the physical model of up-conversion luminescence shows that the IR up-conversion luminescence is resulted from electron trapping process of Sm 3+ energy level. The thermoluminescence peak does not appear below 500 ℃ indicating the trapping energy level is appropriately deep, 800~1400 nm near infrared light can be the release light to realize up-conversion luminescence.展开更多
Super-resolution (SR) is a widely used tech- nology that increases image resolution using algorithmic methods. However, preserving the local edge structure and visual quality in infrared (IR) SR images is challeng...Super-resolution (SR) is a widely used tech- nology that increases image resolution using algorithmic methods. However, preserving the local edge structure and visual quality in infrared (IR) SR images is challenging because of their disadvantages, such as lack of detail, poor contrast, and blurry edges. Traditional and advanced methods maintain the quantitative measures, but they mostly fail to preserve edge and visual quality. This paper proposes an algorithm based on high frequency layer features. This algorithm focuses on the IR image edge texture in the reconstruction process. Experimental results show that the mean gradient of the IR image reconstructed by the proposed algorithm increased by 1.5, 1.4, and 1.2 times than that of the traditional algorithm based on L1- norm, L2-norm, and traditional mixed norm, respectively. The peak signal-to-noise ratio, structural similarity index, and visual effect of the reconstructed image also improved.展开更多
基金supported by the SSRF Phase-II Beamline Project.
文摘The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved scale.This combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme conditions.Moreover,ED-XAS and SR-IR can be used independently in the two branches of the D-Line.The ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample position.An exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy resolution.The focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 keV.Using one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be realized.Several distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.
文摘Europium and samarium co-doped strontium sulfide (SrS∶Eu, Sm) infrared up-conversion phosphor was synthesized through calcining the precursor, which prepared by wet-method with strontium carbonate (SrCO_3), sulphur (S), europium oxide (Eu_2O_3) and samarium oxide (Sm_2O_3) as the starting materials, lithium fluoride (LiF) as the fluxing agent, at 750~1200 ℃ in carbon-reducing atmosphere. XRD analysis shows that SrS crystal structure is formed at 750 ℃, most completely at 1100 ℃. The IR up-conversion luminescence properties were characterized by excitation, emission, up-conversion excitation, up-conversion emission and thermoluminescence spectra. The spectral analysis associated with the physical model of up-conversion luminescence shows that the IR up-conversion luminescence is resulted from electron trapping process of Sm 3+ energy level. The thermoluminescence peak does not appear below 500 ℃ indicating the trapping energy level is appropriately deep, 800~1400 nm near infrared light can be the release light to realize up-conversion luminescence.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 61275099 and 6 1671094) and the Natural Science foundation of Chongqing Science and Technology Commission (No, CSTC2015JCYJA40032).
文摘Super-resolution (SR) is a widely used tech- nology that increases image resolution using algorithmic methods. However, preserving the local edge structure and visual quality in infrared (IR) SR images is challenging because of their disadvantages, such as lack of detail, poor contrast, and blurry edges. Traditional and advanced methods maintain the quantitative measures, but they mostly fail to preserve edge and visual quality. This paper proposes an algorithm based on high frequency layer features. This algorithm focuses on the IR image edge texture in the reconstruction process. Experimental results show that the mean gradient of the IR image reconstructed by the proposed algorithm increased by 1.5, 1.4, and 1.2 times than that of the traditional algorithm based on L1- norm, L2-norm, and traditional mixed norm, respectively. The peak signal-to-noise ratio, structural similarity index, and visual effect of the reconstructed image also improved.