This study proposes a three-dimensional (3D) particle image velocimetry (PIV) method using W- shaped light sheet and color PIV with a digital SLR camera. The uncertainty of the velocity measurement was also studied an...This study proposes a three-dimensional (3D) particle image velocimetry (PIV) method using W- shaped light sheet and color PIV with a digital SLR camera. The uncertainty of the velocity measurement was also studied and it was acceptable. The spatial resolution of the z-direction has much room for improvement by increasing the number of cameras. When applied to the velocity distribution measurement of a thermal vertical buoyant plume, the proposed 3D PIV method is found to be very effective for studying thermal structures and well suited for measuring the airflow velocity field.展开更多
We present a threedimensional(3D)isotropic imaging of mouse brain using light-sheet fuo-rescent microscopy(LSFM)in conjumction with a multi-view imaging computation.Unlike common single view LSFM is used for mouse bra...We present a threedimensional(3D)isotropic imaging of mouse brain using light-sheet fuo-rescent microscopy(LSFM)in conjumction with a multi-view imaging computation.Unlike common single view LSFM is used for mouse brain imaging,the brain tissue is 3D imaged under eight views in our study,by a home-built selective plane ilumination microscopy(SPIM).An output image containing complete structural infornation as well as significantly improved res olution(~4 times)are then computed based on these eight views of data,using a bead-guided multi-view registration and deconvolution.With superior imaging quality,the astrocyte and pyrarmidal neurons together with their subcellular nerve fbers can be clearly visualized and segmented.With further incuding other computational methods,this study can be potentially scaled up to map the conectome of whole mouse brain with a simple light.sheet microscope.展开更多
The dependence of the performance of organic light-emitting devices(OLEDs) on the sheet resistance of indiumtin-oxide(ITO) anodes was investigated by measuring the steady state current density brightness voltage c...The dependence of the performance of organic light-emitting devices(OLEDs) on the sheet resistance of indiumtin-oxide(ITO) anodes was investigated by measuring the steady state current density brightness voltage characteristics and the electroluminescent spectra. The device with a higher sheet resistance anode shows a lower current density, a lower brightness level, and a higher operation voltage. The electroluminescence(EL) efficiencies of the devices with the same structure but different ITO anodes show more complicated differences. Furthermore, the shift of the light-emitting zone toward the anode was found when an anode with a higher sheet resistance was used. These performance differences are discussed and attributed to the reduction of hole injection and the increase in voltage drop over ITO anode with the increase in sheet resistance.展开更多
The design of optical instruments is an active subject due to improvement in lens techniques, fabrication technology, and data handling capacity. Much remains to do to expand its application to phytopathology, which w...The design of optical instruments is an active subject due to improvement in lens techniques, fabrication technology, and data handling capacity. Much remains to do to expand its application to phytopathology, which would be in particular quite useful to improve crop growth monitoring in countries like Mali. An optical multimodal system for plant samples has been developed to improve the characterization of leaf disease symptoms, provide information on their effects, and avoid their spread. Potentially inexpensive components (laser, lens, turntables camera and sample, filter, lens, camera and computer) have been selected, assembled and aligned on an optical table into a multimodal system operating in transmission, reflection, diffusion and fluorescence. The illumination and observation angles can be adjusted to optimize viewing conditions in the four modes. This scientific contribution has been an initiation into the design and implementation of an optical instrument. Initial results are shown and will now be extended in cooperation with agronomic laboratories in African countries for tests on specific plant diseases in relation with prevailing climate conditions.展开更多
ZnO as a semiconductor photocatalyst is widely applied in the photodegradation of organic pollutants. Its photocatalytic activity is greatly decreased because of the recombination of photoexcited electrons and holes i...ZnO as a semiconductor photocatalyst is widely applied in the photodegradation of organic pollutants. Its photocatalytic activity is greatly decreased because of the recombination of photoexcited electrons and holes in the bulk. In this work, ZnO sheets are synthesized by adjusting the NaOH concentration under light irradiation at room temperature. Compared with ZnO particles, the ZnO sheets prepared with a light-assisted growth method exhibit a higher rate of photodegradation of methylene blue under UV visible light irradiation. The improved photodegradation rate is mainly attributed to the shortened transport distance of photoexcited electrons, the high surface area, and the surface atom structure modified by the light-assisted growth process. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.展开更多
The assembly of metal ions Zn2+, Co2+ and H2E2Ge2O3 ligand under mild hydro- thermal conditions leads to a mixed 3D transition zinc-cobalt-organogermanate framework, Zn0.88Co0.12(E2Ge2O3) (1, E = -CH2CH2COO-). T...The assembly of metal ions Zn2+, Co2+ and H2E2Ge2O3 ligand under mild hydro- thermal conditions leads to a mixed 3D transition zinc-cobalt-organogermanate framework, Zn0.88Co0.12(E2Ge2O3) (1, E = -CH2CH2COO-). The structure was determined by single-crystal X-ray diffraction and further characterized by IR spectroscopy, elemental analysis, energy- dispersive X-ray analysis, inductively coupled plasma, powder X-ray diffraction, thermogra- vimetric analysis and fluorescence spectroscopy. Compound 1 crystallizes in the chiral space group P212121, with a = 4.9096(5), b = 8.9031(11), c = 24.046(3) A, V = 1051.0(2) A3, C6H8Ge2O7Zn0.88Co0.12, Mr = 401.88, Z = 4, Dc = 2.540 g.cm-1,μ = 7.875 mm-1, F(000) = 775, GOF= 1.016, the final R = 0.0324 and wR = 0.0642. The structure ofl is built up by Ge-O sheets with Ge6 rings and Zn/Co-carboxyl layers. It should be mentioned that although the whole E2Ge2O32- ligand exhibits only one kind of coordination mode, it plays two roles in forming the structure: SBU and linker. In this situation, the E group of H2E2Ge2O3 ligand becomes a determining factor for structural dimensionality. In addition, it displays blue-violet emission light and shows high thermostability.展开更多
Fluorescence imaging through the second near-infrared window(NIR-Ⅱ,1000–1700 nm) allows in-depth imaging.However, current imaging systems use wide-field illumination and can only provide low-contrast 2D information,...Fluorescence imaging through the second near-infrared window(NIR-Ⅱ,1000–1700 nm) allows in-depth imaging.However, current imaging systems use wide-field illumination and can only provide low-contrast 2D information, without depth resolution. Here, we systematically apply a light-sheet illumination, a time-gated detection, and a deep-learning algorithm to yield high-contrast high-resolution volumetric images. To achieve a large Fo V(field of view) and minimize the scattering effect, we generate a light sheet as thin as 100.5 μm with a Rayleigh length of 8 mm to yield an axial resolution of 220 μm. To further suppress the background, we time-gate to only detect long lifetime luminescence achieving a high contrast of up to 0.45 Icontrast. To enhance the resolution, we develop an algorithm based on profile protrusions detection and a deep neural network and distinguish vasculature from a low-contrast area of 0.07 Icontrast to resolve the 100μm small vessels. The system can rapidly scan a volume of view of 75 × 55 × 20 mm3and collect 750 images within 6mins. By adding a scattering-based modality to acquire the 3D surface profile of the mice skin, we reveal the whole volumetric vasculature network with clear depth resolution within more than 1 mm from the skin. High-contrast large-scale 3D animal imaging helps us expand a new dimension in NIR-Ⅱ imaging.展开更多
文摘This study proposes a three-dimensional (3D) particle image velocimetry (PIV) method using W- shaped light sheet and color PIV with a digital SLR camera. The uncertainty of the velocity measurement was also studied and it was acceptable. The spatial resolution of the z-direction has much room for improvement by increasing the number of cameras. When applied to the velocity distribution measurement of a thermal vertical buoyant plume, the proposed 3D PIV method is found to be very effective for studying thermal structures and well suited for measuring the airflow velocity field.
基金funding support from 1000 Youth Talents Plan of China (P.F.)Fundamental Research Program of Shenzhen (P.F.,JCYJ20160429182424047)+1 种基金National Science Foundation of China (NSFC31571002,D.Z)Graduates'Innovation Fund of Huazhong University of Science and Technology (5003182004).
文摘We present a threedimensional(3D)isotropic imaging of mouse brain using light-sheet fuo-rescent microscopy(LSFM)in conjumction with a multi-view imaging computation.Unlike common single view LSFM is used for mouse brain imaging,the brain tissue is 3D imaged under eight views in our study,by a home-built selective plane ilumination microscopy(SPIM).An output image containing complete structural infornation as well as significantly improved res olution(~4 times)are then computed based on these eight views of data,using a bead-guided multi-view registration and deconvolution.With superior imaging quality,the astrocyte and pyrarmidal neurons together with their subcellular nerve fbers can be clearly visualized and segmented.With further incuding other computational methods,this study can be potentially scaled up to map the conectome of whole mouse brain with a simple light.sheet microscope.
基金Supported by the National Natural Science Foundation of China(No. 20372060), the Key National Natural Science Foundationof China(No. 20131010), the Important National Natural Science Foundation of China(No. 20490210), the"863"Program(Nos.2002AA302105 and 2002AA324080) and Foreign Communion &Cooperation of National Natural Science Foundation of China(No.20340420326).
文摘The dependence of the performance of organic light-emitting devices(OLEDs) on the sheet resistance of indiumtin-oxide(ITO) anodes was investigated by measuring the steady state current density brightness voltage characteristics and the electroluminescent spectra. The device with a higher sheet resistance anode shows a lower current density, a lower brightness level, and a higher operation voltage. The electroluminescence(EL) efficiencies of the devices with the same structure but different ITO anodes show more complicated differences. Furthermore, the shift of the light-emitting zone toward the anode was found when an anode with a higher sheet resistance was used. These performance differences are discussed and attributed to the reduction of hole injection and the increase in voltage drop over ITO anode with the increase in sheet resistance.
文摘The design of optical instruments is an active subject due to improvement in lens techniques, fabrication technology, and data handling capacity. Much remains to do to expand its application to phytopathology, which would be in particular quite useful to improve crop growth monitoring in countries like Mali. An optical multimodal system for plant samples has been developed to improve the characterization of leaf disease symptoms, provide information on their effects, and avoid their spread. Potentially inexpensive components (laser, lens, turntables camera and sample, filter, lens, camera and computer) have been selected, assembled and aligned on an optical table into a multimodal system operating in transmission, reflection, diffusion and fluorescence. The illumination and observation angles can be adjusted to optimize viewing conditions in the four modes. This scientific contribution has been an initiation into the design and implementation of an optical instrument. Initial results are shown and will now be extended in cooperation with agronomic laboratories in African countries for tests on specific plant diseases in relation with prevailing climate conditions.
基金support from the Institute of Metal Research,Chinese Academy of Sciencessupported by the National Science Fund of China(51202105,21366020)+1 种基金the Natural Science Foundation of Jiangxi Province(20151BAB216006)the Science and Technology Project of Education Department of Jiangxi Province(GJJ14109)
文摘ZnO as a semiconductor photocatalyst is widely applied in the photodegradation of organic pollutants. Its photocatalytic activity is greatly decreased because of the recombination of photoexcited electrons and holes in the bulk. In this work, ZnO sheets are synthesized by adjusting the NaOH concentration under light irradiation at room temperature. Compared with ZnO particles, the ZnO sheets prepared with a light-assisted growth method exhibit a higher rate of photodegradation of methylene blue under UV visible light irradiation. The improved photodegradation rate is mainly attributed to the shortened transport distance of photoexcited electrons, the high surface area, and the surface atom structure modified by the light-assisted growth process. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.
基金supported by the Natural Science Fund for Young Scholars of Fujian Province(No. 2011J05018)the Fund for Young Scholars from Fujian Agriculture and Forestry University (No. 2011xjj06)
文摘The assembly of metal ions Zn2+, Co2+ and H2E2Ge2O3 ligand under mild hydro- thermal conditions leads to a mixed 3D transition zinc-cobalt-organogermanate framework, Zn0.88Co0.12(E2Ge2O3) (1, E = -CH2CH2COO-). The structure was determined by single-crystal X-ray diffraction and further characterized by IR spectroscopy, elemental analysis, energy- dispersive X-ray analysis, inductively coupled plasma, powder X-ray diffraction, thermogra- vimetric analysis and fluorescence spectroscopy. Compound 1 crystallizes in the chiral space group P212121, with a = 4.9096(5), b = 8.9031(11), c = 24.046(3) A, V = 1051.0(2) A3, C6H8Ge2O7Zn0.88Co0.12, Mr = 401.88, Z = 4, Dc = 2.540 g.cm-1,μ = 7.875 mm-1, F(000) = 775, GOF= 1.016, the final R = 0.0324 and wR = 0.0642. The structure ofl is built up by Ge-O sheets with Ge6 rings and Zn/Co-carboxyl layers. It should be mentioned that although the whole E2Ge2O32- ligand exhibits only one kind of coordination mode, it plays two roles in forming the structure: SBU and linker. In this situation, the E group of H2E2Ge2O3 ligand becomes a determining factor for structural dimensionality. In addition, it displays blue-violet emission light and shows high thermostability.
基金Technology Program(KQTD20170810110913065,20200925174735005)National Natural Science Foundation of China(62005116,51720105015)Guangdong Provincial Key Laboratory of Advanced Biomaterials(2022B1212010003).
文摘Fluorescence imaging through the second near-infrared window(NIR-Ⅱ,1000–1700 nm) allows in-depth imaging.However, current imaging systems use wide-field illumination and can only provide low-contrast 2D information, without depth resolution. Here, we systematically apply a light-sheet illumination, a time-gated detection, and a deep-learning algorithm to yield high-contrast high-resolution volumetric images. To achieve a large Fo V(field of view) and minimize the scattering effect, we generate a light sheet as thin as 100.5 μm with a Rayleigh length of 8 mm to yield an axial resolution of 220 μm. To further suppress the background, we time-gate to only detect long lifetime luminescence achieving a high contrast of up to 0.45 Icontrast. To enhance the resolution, we develop an algorithm based on profile protrusions detection and a deep neural network and distinguish vasculature from a low-contrast area of 0.07 Icontrast to resolve the 100μm small vessels. The system can rapidly scan a volume of view of 75 × 55 × 20 mm3and collect 750 images within 6mins. By adding a scattering-based modality to acquire the 3D surface profile of the mice skin, we reveal the whole volumetric vasculature network with clear depth resolution within more than 1 mm from the skin. High-contrast large-scale 3D animal imaging helps us expand a new dimension in NIR-Ⅱ imaging.