A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemen...A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows： orthorhombic system, space group P212121 with a = 13.8287（7）, b = 14.0715（7）, c = 25.7403（12） A^°, V = 5008.8（4） A^°3, Mr = 1333.08, Z = 4, F（000） = 2644, Dc = 1.768 g/cm^3, μ（MoKα） = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 （I 〉 2σ（I））. Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism （VCD） spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.展开更多
A new metal-organic framework, {[Cd（DPA）（OBA）]＇（HzO）}n （1, DPA = 4,4＂-dipyri- dylamine, H2OBA = 4,4＂-oxybisbenzoic acid）, has been synthesized and characterized by elemental analysis, IR and single-crystal ...A new metal-organic framework, {[Cd（DPA）（OBA）]＇（HzO）}n （1, DPA = 4,4＂-dipyri- dylamine, H2OBA = 4,4＂-oxybisbenzoic acid）, has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Single-crystal X-ray analysis shows that it is a 3-D framework. Complex 1 crystallizes in monoclinic, space group C2/c with a = 21.699（7）, b = 12.192（4）, c = 17.566（5） A, β = 105.254（5）°, V = 4483.43 A3, Z = 8, Dc = 1.653 g/cm3, p = 1.021 mm^-1], F（000） = 2240, the final R = 0.0307, wR = 0.0867 （I 〉 2σ（I））. Complex I exhibits a rare three-dimensional highly 8-connected LOMFOI topology with a point symbol of {424＂64}. Thermogravimetric analysis shows that the decomposition temperature of the host framework of the complex is above 400 ℃.展开更多
为提高水域鱼类资源监测的自动化程度和实时分析能力,结合YOLOv8X(You only look once version 8-extra large)目标检测模型、ByteTrack(ByteTrack:a strong baseline for multi-object tracking)算法与双频识别声呐(Dual-frequency ide...为提高水域鱼类资源监测的自动化程度和实时分析能力,结合YOLOv8X(You only look once version 8-extra large)目标检测模型、ByteTrack(ByteTrack:a strong baseline for multi-object tracking)算法与双频识别声呐(Dual-frequency identification sonar,DIDSON)数据,开发了1种快速、准确的鱼类目标识别与计数方法。实验结果表明,YOLOv8X与ByteTrack联合方法与传统的Echoview软件识别精度接近(偏差率仅为1.36%),但处理时间显著减少(单条测线从约30 min减少至约3 min),表现出较强的实时处理能力和泛化性能。同时,通过重复实验验证了该方法的稳定性,确认其在不同场景中的可靠性。本研究方法与成果为水域鱼类资源的自动化监测提供了可靠的技术支持,可广泛地应用于大范围高频次的渔业资源监测与管理工作中。展开更多
基金supported by National Natural Science Foundation of China(21401147)Basic Research Program of Natural Science from Shaanxi Provincial Government(2015JQ2032)+2 种基金Scientific Research Program from Education Department of Shaanxi Provincial Government(2013JK0654)Opening Foundation from State Key Laboratory of Coordination Chemistry in Nanjing University(201219)the Program for Distinguished Young Scholars of Xi’an Polytechnic University(201403)
文摘A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows： orthorhombic system, space group P212121 with a = 13.8287（7）, b = 14.0715（7）, c = 25.7403（12） A^°, V = 5008.8（4） A^°3, Mr = 1333.08, Z = 4, F（000） = 2644, Dc = 1.768 g/cm^3, μ（MoKα） = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 （I 〉 2σ（I））. Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism （VCD） spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.
基金supported by the National Ministry of Science and Technology of China(2012CB821702)the National Science Foundation of China(21073192,21203194 and 21233009)the Science Foundation of CAS and Fujian Province for research funding support(KJCX2-YW-H20)
文摘A new metal-organic framework, {[Cd（DPA）（OBA）]＇（HzO）}n （1, DPA = 4,4＂-dipyri- dylamine, H2OBA = 4,4＂-oxybisbenzoic acid）, has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Single-crystal X-ray analysis shows that it is a 3-D framework. Complex 1 crystallizes in monoclinic, space group C2/c with a = 21.699（7）, b = 12.192（4）, c = 17.566（5） A, β = 105.254（5）°, V = 4483.43 A3, Z = 8, Dc = 1.653 g/cm3, p = 1.021 mm^-1], F（000） = 2240, the final R = 0.0307, wR = 0.0867 （I 〉 2σ（I））. Complex I exhibits a rare three-dimensional highly 8-connected LOMFOI topology with a point symbol of {424＂64}. Thermogravimetric analysis shows that the decomposition temperature of the host framework of the complex is above 400 ℃.
文摘为提高水域鱼类资源监测的自动化程度和实时分析能力,结合YOLOv8X(You only look once version 8-extra large)目标检测模型、ByteTrack(ByteTrack:a strong baseline for multi-object tracking)算法与双频识别声呐(Dual-frequency identification sonar,DIDSON)数据,开发了1种快速、准确的鱼类目标识别与计数方法。实验结果表明,YOLOv8X与ByteTrack联合方法与传统的Echoview软件识别精度接近(偏差率仅为1.36%),但处理时间显著减少(单条测线从约30 min减少至约3 min),表现出较强的实时处理能力和泛化性能。同时,通过重复实验验证了该方法的稳定性,确认其在不同场景中的可靠性。本研究方法与成果为水域鱼类资源的自动化监测提供了可靠的技术支持,可广泛地应用于大范围高频次的渔业资源监测与管理工作中。
