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Growth and optical properties of ytterbium and rare earth ions codoped CaF2-SrF2 eutectic solid-solution(RE=Y^(3+),Gd^(3+),La^(3+))

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Journal of Rare Earths 2021年第4期39卷 390-397页

作者： Binbin Jiang Lihe Zheng Dapeng Jiang Handi Yin Jiangang Zheng qiuhong yang Guofeng Cheng Liangbi Su School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201899China School of Physics and Astronomy Yunnan UniversityKunming 650091China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Science and Technology on High Energy Laser China Academy of Engineering and PhysicsMianyang 621900China

Ytterbium and rare earth ions(RE=Y,Gd,La)codoped CaF_(2)-SrF_(2)single crystals(3 at%Yb,6 at%RE:CaF_(2)-SrF_(2))were fabricated by temperature gradient technology(TGT).All the space groups remain the same Fm3m as that of Yb:CaF_(2)-SrF_(2).The lattice parameter a,unit cell volume V,as well as bond length of Ca/Sr-F and F-F increase in the sequence of rare-earth ions radius Y^(3+)

关键词： Rare earth ions Optical materials Crystal growth Luminescence Raman spectroscopy

Study on photoluminescence of thermally treated Bi_(12)GeO_(20) and Mo:Bi_(12)GeO_(20) crystals

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Science China(Technological Sciences) 2011年第5期54卷 1287-1291页

作者： YU PingSheng SU LiangBi TANG HuiLi GUO Xin ZHAO HengYu yang qiuhong XU Jun School of Materials Science and Engineering Shanghai University Shanghai 200072 China Key Laboratory of Tranaparent and Opto-Functional Inorganic Materials Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Photoluminescence (PL) of Bi12GeO20 and Mo doped Bi12GeO20 (Mo: Bi12GeO20) crystals in visible and near-infrared (NIR) spectral regions were studied. X-ray diffraction analysis, absorption and Raman scattering spectra of these crystals were also measured. Pure Bi12GeO20 after annealing in N2 atmosphere at 450 oC and 550 °C show predominant emissions at about 745 and 1250 nm bands, while the emission peaks of Mo:Bi12GeO20 crystals untreated or after annealing in Ar at 300 °C are at around 538 and 1165 nm. The results suggest that annealing induces intrinsic luminescence of Bi in pure Bi12GeO20 at room temperature and Mo influences the luminescence centers of Bi12GeO20. The emission peaks of Bi12GeO20 and Mo: Bi12GeO20 probably owe to lower-valent Bi ions.

关键词： photoluminescence Bi12GeO20 Mo: Bi12GeO20 thermally treated

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用体视学方法分析透明氧化铝陶瓷的显微结构

硅酸盐学报 2006年第1期34卷 30-33页

作者：杨秋红丁君上海大学电子信息材料系上海200072

以高纯Al2O3(>99.9%)粉末为原料,采用无压烧结工艺制备了透明性良好的Al2O3透明陶瓷,并测定其体积密度和透过率。用体视学方法推导论证得到三维参数,即:表面积密度、总自由程以及体积密度和透明陶瓷透过率的关系,并和实际测得的透过率... 详细信息

以高纯Al2O3(>99.9%)粉末为原料,采用无压烧结工艺制备了透明性良好的Al2O3透明陶瓷,并测定其体积密度和透过率。用体视学方法推导论证得到三维参数,即:表面积密度、总自由程以及体积密度和透明陶瓷透过率的关系,并和实际测得的透过率进行比较。实验结果表明:体视学方法预测的透过率和实际测得的透过率很好地一致。因此,将体视学方法用于透明陶瓷显微结构的分析是可行的。

关键词：体视学方法透明陶瓷显微结构透过率

Improved Gossypium raimondii genome using a Hi-C-based proximity-guided assembly

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Journal of Cotton Research 2021年第3期4卷 261-267页

作者： yang qiuhong ZUO Dongyun CHENG Hailiang ZHANG Youping WANG Qiaolian JAVARIA Ashraf FENG Xiaoxu LI Simin CHEN Xiaoqin LIU Shang SONG Guoli State Key Laboratory of Cotton Biology Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyangHenanChina

Introduction:Genome sequence plays an important role in both basic and applied *** raimondii,the putative contributor of the D subgenome of upland cotton(***,highlights the need to improve the genome quality rapidly and ***:We performed Hi-C sequencing of *** and reassembled its genome based on a set of new Hi-C data and previously published *** also compared the reassembled genome sequenee with the previously published G raimondii genomes for gene and genome sequence ***:A total of 9842%of scaffold sequences were clustered successfully,among which 99.72%of the clustered sequences were ordered and 99.92%of the ordered sequences were oriented with *** evaluation of results by heat-map and collinearity analysis revealed that the current reassembled genome is significantly improved than the previous one(Nat Genet 44:98-1103,2012).Conclusion:This improvement in G raimondii genome not only provides a better reference to increase study efficiency but also offers a new way to assemble cotton ***,Hi-C data of *** may be used for 3D structure research or regulating analysis.

关键词： Gossypium raimondii Hi-C Genome assembly Heatmap and collinearity

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乡村振兴视域下的新型职业农民培育浅析

职教论坛 2019年第11期35卷 107-111页

作者：杨秋红潍坊科技学院马克思主义学院山东大学马克思主义学院

新型职业农民培育对于推动农业农村改革发展,全面落实乡村振兴战略意义重大。当前我国新型职业农民培育呈现出政府支持明显加大但外部支撑仍显薄弱、培育工作不断深化但培育体系有待健全、培育范围不断扩大但培育主体有待挖掘的状况。... 详细信息

新型职业农民培育对于推动农业农村改革发展,全面落实乡村振兴战略意义重大。当前我国新型职业农民培育呈现出政府支持明显加大但外部支撑仍显薄弱、培育工作不断深化但培育体系有待健全、培育范围不断扩大但培育主体有待挖掘的状况。应把握乡村振兴战略实施带来的契机,发挥政府职能、优化外部环境,构建科学的培育体系、提高培育的精准性,拓宽培育主体来源、不断培育新能人。

关键词：乡村振兴新型职业农民农民培育

掺Yb^(3+)的氧化镧钇透明激光陶瓷的光谱特性

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硅酸盐学报 2006年第6期34卷 675-678页

作者：张红伟杨秋红徐军上海大学材料科学与工程学院上海200072 中国科学院上海光学精密机械研究所上海201800

采用传统陶瓷烧结工艺,在无压还原气氛中低温制备了Yb3+掺杂量高达10％(按摩尔计)的透明性良好的氧化镧钇激光陶瓷,研究了其在室温的吸收光谱、发射光谱以及荧光寿命。结果表明:掺Yb3+氧化镧钇透明激光陶瓷具有宽的吸收和发射光谱以及... 详细信息

采用传统陶瓷烧结工艺,在无压还原气氛中低温制备了Yb3+掺杂量高达10％(按摩尔计)的透明性良好的氧化镧钇激光陶瓷,研究了其在室温的吸收光谱、发射光谱以及荧光寿命。结果表明:掺Yb3+氧化镧钇透明激光陶瓷具有宽的吸收和发射光谱以及长的荧光寿命。吸收峰位于902,942nm 和968 nm处,吸收截面分别为0.31×10-20,0．45×10-20 cm2和0．53×10-20 cm2;主发射峰位于1032nm和1075 nm处,发射截面分别为1．05×10-20 cm2 和0．87×10-20 cm2,上能级荧光寿命分别为1．17ms和1．04ms。掺Yb3+氧化镧钇透明激光陶瓷大的吸收和发射截面以及长的荧光寿命有利于高效吸收泵浦能量,是一种适合于高效、高功率激光二极管泵浦的固体激光介质。

关键词：氧化镧钇透明陶瓷激光陶瓷:光谱特性镱离子掺杂

Gain and laser performance of heavily Er-doped silica fiber fabricated by MCVD combined with the sol-gel method

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Chinese Optics Letters 2021年第11期19卷 27-31页

作者： Qiubai yang Yan Jiao Chunlei Yu Chongyun Shao Fengguang Lou Shikai Wang Lei Zhang qiuhong yang Lili Hu School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Key Laboratory of High Power Laser Materials Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

In this work, a heavily Er-doped fiber with an 8 μm core diameter and a numerical aperture of 0.13 was prepared by the modified chemical vapor deposition(MCVD) technique combined with the sol-gel method. The background loss and absorption coefficient at 1530 nm were measured to be 20 d B/km and 128 d B/m, respectively. Thanks to the sol-gel method, the fiber showed a good doping homogeneity, which was confirmed through unsaturable absorption measurement. The net gains of three 25, 45, and 75-cm-long fibers were measured in the range of 1520 to 1600 nm, and the highest gain reached above 23 d B at both 1530 and 1560 nm in 25 and 75-cm-long fibers, respectively. The short-cavity laser performance was measured using centimeter-scale fibers. The maximum output power of 12 m W was demonstrated in a 6.5-cm-long active fiber with a slope efficiency of 20.4%. Overall, the prepared heavily Er-doped silica fiber is a promising item to be applied in a high-repetition-rate or single-frequency fiber laser.

关键词： erbium-doped fiber short-cavity fiber laser sol-gel method

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氟锆酸盐玻璃析晶动力学研究

无机材料学报 1995年第1期10卷 17-22页

作者：杨秋红姜中宏中国科学院上海光学精密机械研究所

本文用差示热分析ＤＴＡ研究了ＮａＦ和ＮａＣｌ的引入对氟锆酸盐玻璃析晶动力学参数的影响，指出ＮａＦ和ＮａＣｌ的引入使氟锆酸盐玻璃析晶活化能下降，Ｔｘ—Ｔｇ增加，改善了玻璃形成能力．用Ａｕｇｉｓ－Ｂｅｎｎｅｔｔ法及修正Ｋ... 详细信息

本文用差示热分析ＤＴＡ研究了ＮａＦ和ＮａＣｌ的引入对氟锆酸盐玻璃析晶动力学参数的影响，指出ＮａＦ和ＮａＣｌ的引入使氟锆酸盐玻璃析晶活化能下降，Ｔｘ—Ｔｇ增加，改善了玻璃形成能力．用Ａｕｇｉｓ－Ｂｅｎｎｅｔｔ法及修正Ｋｉｓｓｉｎｇｅｒ法处理实验结果，所得析晶活化能基本一致，而由Ａｕｇｉｓ－Ｂｅｎｎｅｔｔ法得到的频率因子较由修正Ｋｉｓｓｉｎｇｅｒ法得到的频率因子小一个数量级．同时用一种新的析晶动力学判据Ｋｙ（Ｔ）＝ｖｅｘｐ（－Ｅ／ＲＴ×△Ｔ／Ｔｍ（△Ｔ＝Ｔｘ—Ｔｇ）来判断氟锆酸盐玻璃形成能力，并与别的判据进行了分析比较．析晶活化能与玻璃的热稳定性有关．

关键词：玻璃析晶动力学氟锆酸玻璃

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具有n个小时滞脉冲系统的周期解

应用数学学报 2013年第1期36卷 165-175页

作者：杨秋鸿冯春华广西师范大学数学科学学院桂林541004

本文考虑有n个小时滞的脉冲系统,利用隐函数存在性定理证明了该系统时滞充分小时,系统的周期解存在性,推广了已有的相关结论.

关键词：小时滞脉冲周期解隐函数存在性定理