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Preparation and upconversion luminescence modification of YbPO4:Er3+inverse opal heterostructure

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Journal of Rare Earths 2017年第12期35卷 1180-1185页

作者： Zhuangzhuang Chai Zhengwen Yang Anjun Huang Chengye Yu Jianbei Qiu zhiguo song College of Materials Science and Engineering Kunming University of Science and Technology

Photonic crystal heterostructures composed of YbPO4：Er^（3＋） inverse opal and polystyrene opal were prepared via a template-assisted process, which exhibited two photonic band gaps. The microstructure,phase and optical properties of photonic crystal heterostructures were investigated by x-ray diffraction,scanning electron microscopy, fluorescence spectroscopy, absorption spectroscopy, fluorescence lifetime,etc. The upconversion emission suppression caused by single photonic band gap from the following YbPO4：Er^（3＋） inverse opal or the upper opal was observed. The upconversion luminescence was strongly suppressed due to the two photonic band gap overlapping effect caused by the following YbPO4：Er^（3＋） inverse opal or the upper opal. The modified mechanisms of upconversion luminescence were discussed by the upconversion luminescence lifetime of YbPO4：Er^（3＋） photonic crystal heterostructures. The results demonstrated the modified upconversion luminescence is attributed to the photon trapping caused by Bragg reflection of photonic crystal heterostructures.

关键词： Photonic crystal Heterostructures Upconversion luminescence Modification

Rate compatible reconciliation for continuous-variable quantum key distribution using Raptor-like LDPC codes

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Science China(Physics,Mechanics & Astronomy) 2021年第6期64卷 26-34页

作者： Chao Zhou Xiang Yu Wang zhiguo Zhang song Yu ZiYang Chen Hong Guo State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Advanced Optical Communication Systems and NetworksDepartment of Electronicsand Center for Quantum Information TechnologyPeking UniversityBeijing 100871China

In the practical continuous-variable quantum key distribution(CV-QKD)system,the postprocessing process,particularly the error correction part,significantly impacts the system ***-edge type low-density parity-check(MET-LDPC)codes are suitable for CV-QKD systems because of their Shannon-limit-approaching performance at a low signal-to-noise ratio(SNR).However,the process of designing a low-rate MET-LDPC code with good performance is extremely ***,we introduce Raptor-like LDPC(RL-LDPC)codes into the CV-QKD system,exhibiting both the rate compatible property of the Raptor code and capacity-approaching performance of MET-LDPC ***,this technique can significantly reduce the cost of constructing a new *** design the RL-LDPC matrix with a code rate of 0.02 and easily and effectively adjust this rate from 0.016 to *** results show that we can achieve more than 98%reconciliation efficiency in a range of code rate variation using only one RL-LDPC code that can support high-speed decoding with an SNR less than-16.45 d *** code allows the system to maintain a high key extraction rate under various SNRs,paving the way for practical applications of CV-QKD systems with different transmission distances.

关键词： continuous-variable quantum key distribution reconciliation Raptor-like LDPC codes

Variations of temperature, salinity and current in the southern tidal passage of the Hangzhou Bay, China

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Acta Oceanologica Sinica 2016年第3期35卷 30-37页

作者： HE zhiguo HUANGFU Kailong YUAN Yeping song Dan LI Li Ocean College Zhejiang University State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration

Field surveys covering a spring-neap tidal period were conducted to investigate the characteristics of tidal dynamics within a curved channel in the southern Hangzhou Bay, China. The channel has a maximum depth of more than 100 m with an average tidal range of 2.5 m, serving as the main tidal passage in the southern part of the Hangzhou Bay. Water salinity, temperature and velocity data were collected from the ship-based transects and mooring measurements. During flood tide, the tidal current intrudes into the Hangzhou Bay through the northern side of the channel with a maximum velocity of about 2 m/s, while retreats through the southern side during ebb tide with a maximum velocity of 1.8 m/s. Due to the pressure, density gradients, the Coriolis force and centrifugal effect, a lateral exchange flow is generated as the tidal current relaxes from flood to ebb. Salinity and temperature data show that the water in the channel is weakly stratified during both spring and neap tides in summer ***, mixing in the middle region will be enhanced by the lateral circulation. Mooring data indicate that the temperature and salinity are varying at a frequency similar to tidal current but higher than sea level *** results support the hypothesis that the high frequency salinity and temperature variations could be generated by combination of the tidal current and the lateral exchanging flow.

关键词： macro-tidal estuary mooring observations temperature and salinity variations tidal current curved channel

4,4′-联吡啶桥联的钴配位聚合物的合成、表征及量子化学计算

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人工晶体学报 2024年第9期53卷 1583-1590页

作者：史燚威杨瑞杰张迎春王鑫王敏宋志国渤海大学化学与材料工程学院锦州121013

本文通过溶剂热法以对甲基苯磺酸钠为主配体,4,4′-联吡啶为辅助配体制备了一种结构新颖的钴配位聚合物{[Co(4,4′-bipy)(H_(2)O)_(4)]·(p-CH_(3)C_(6)H_(4)SO_(3))_(2)}_(n)。通过红外光谱、X射线单晶衍射、热重分析、X射线粉末衍射... 详细信息

本文通过溶剂热法以对甲基苯磺酸钠为主配体,4,4′-联吡啶为辅助配体制备了一种结构新颖的钴配位聚合物{[Co(4,4′-bipy)(H_(2)O)_(4)]·(p-CH_(3)C_(6)H_(4)SO_(3))_(2)}_(n)。通过红外光谱、X射线单晶衍射、热重分析、X射线粉末衍射等方法对钴配位聚合物进行了表征。结果表明,{[Co(4,4′-bipy)(H_(2)O)_(4)]·(p-CH_(3)C_(6)H_(4)SO_(3))_(2)}_(n)属于单斜晶系,P2_(1/c)空间群,晶胞参数为a=11.3191(14)Å,b=8.0626(11)Å,c=14.936(2)Å,α=90°,β=92.423(4)°,γ=90°,V=1361.9(3)Å^(3),Z=2。中心金属Co(Ⅱ)离子为六配位略有畸变的八面体构型,通过4,4′-联吡啶中的N原子桥联形成一维无限链状,层间通过配位水分子与对甲基苯磺酸之间的氢键作用进一步扩展成三维超分子结构。并运用Gaussian 09程序对钴配位聚合物中[Co(4,4′-bipy)_(2)(H_(2)O)_(4)]·(p-CH_(3)C_(6)H_(4)SO_(3))结构单元进行了量子化学计算,获得了优化构型。原子电荷分布及前沿占据轨道组成很好地佐证了晶体结构的配位环境。电化学阻抗测试结果证明该配位聚合物的电阻较小,导电性能良好,为其在电化学应用方面提供了一定的理论依据。

关键词：钴配位聚合物溶剂热法晶体结构 4 4′-联吡啶量子化学计算

Reversible 3D optical data storage and information encryption in photo-modulated transparent glass medium

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Light(Science & Applications) 2021年第8期10卷 1485-1493页

作者： Zhen Hu Xiongjian Huang Zhengwen Yang Jianbei Qiu zhiguo song Junying Zhang Guoping Dong College of Materials Science and Engineering Kunming University of Science and Technology650093 KunmingChina. State Key Laboratory of Luminescent Materials and Devices School of Materials Science and EngineeringSouth China University of Technology510640 GuangzhouChina. School of Physics Beihang University100191 BeijingChina

Transparent glass has been identified as a vital medium for three-dimensional(3D)optical information storage and multi-level ***,it has remained a challenge for directly writing 3D patterning inside a transparent glass using semiconductor blue laser instead of high-cost femtosecond ***,we demonstrate that rare earth ions doped transparent glass can be used as 3D optical information storage and data encryption medium based on their reversible transmittance and photoluminescence *** color of tungsten phosphate glass doped with rare earth ions change reversibly from light yellow to blue upon alternating 473 nm laser illumination and temperature stimulation,resulting in the reversible luminescence *** information data could be repeatedly written and erased in arbitrary 3D space of transparent glass,not only showing the ability of the excellent reproducibility and storage capacity,but also opening opportunities in information *** present work expands the application fields of luminescent glass,and it is conducive to develop a novel 3D data storage and information encryption media.

关键词： encryption optical transparent

基于苯磺酸和2,2′-联吡啶双配体的锰配合物的结构及其催化Mannich反应性能和机理

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无机化学学报 2024年第8期40卷 1501-1510页

作者：张迎春史燚威杨瑞杰王鑫宋志国王敏渤海大学化学与材料工程学院锦州121013

由溶剂热法合成了2个锰的超分子配合物[Mn_(2)(2,2'-bipy)_(4)(H_(2)O)Cl_(3)](L_1)·6H_(2)O (1)和[Mn(2,2'-bipy)_(2)(H_(2)O)Cl](L_(2))·3H_(2)O (2)(L_(1)^(-)=对甲基苯磺酸根,L_(2)^(-)=间硝基苯磺酸根,2,2'-bipy=2,2'-联吡啶),并用单晶X射线衍射、红外光谱、热重分析和氮气吸附-脱附测试对其进行了表征。以Mannich反应为探针,研究了2种配合物的催化性能,并通过对比2种配合物的扫描电镜和粉末X射线衍射表征结果,分析了配合物结构对其催化性能的影响。最后通过密度泛函理论预测了配合物的活性位点,利用X射线光电子能谱证明了活性位点的活化作用,进而阐述了配合物催化Mannich反应的机理。

关键词：超分子配合物晶体结构 Mannich反应理论计算催化机理

Joint Optimization of Satisfaction Index and Spectrum Efficiency with Cache Restricted for Resource Allocation in Multi-Beam Satellite Systems

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China Communications 2019年第2期16卷 189-201页

作者： Pei Zhang Xiaohui Wang zhiguo Ma Junde song School of Computer Science Beijing University of Posts and Telecommunications China Academy of Information and Communications Technology

Dynamic resource allocation(DRA) is a key technology to improve system performances in GEO multi-beam satellite systems. And, since the cache resource on the satellite is very valuable and limited, DRA problem under restricted cache resources is also an important issue to be studied. This paper mainly investigates the DRA problem of carrier resources under certain cache constraints. What's more, with the aim to satisfy all users' traffic demands as more as possible, and to maximize the utilization of the bandwidth, we formulate a multi-objective optimization problem(MOP) where the satisfaction index and the spectrum efficiency are jointly optimized. A modified strategy SA-NSGAII which combines simulated annealing(SA) and non-dominated sorted genetic algorithm-II(NSGAII) is proposed to approximate the Pareto solution to this MOP problem. Simulation results show the effectiveness of the proposed algorithm in terms of satisfaction index, spectrum efficiency, occupied cache, and etc.

关键词： GEO multi-beam satellite system dynamic resource allocation SA-NSGAII cache satisfaction index spectrum efficiency

Color tunable and white light emitting via energy transfer in single-phase BiOCl:Er^(3+),Sm^(3+) phosphors for WLEDs

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Journal of Rare Earths 2018年第3期36卷 231-237页

作者： Xiangzhou Zhang Yongjin Li Rui Hu Zuyuan Xu Jianbei Qiu Zhengwen Yang zhiguo song School of Materials Science and Engineering Kunming University of Science and Technology School of Materials Science and Engineering Sun Yat-sen University

BiOCl crystal shows potential as efficient optical host due to its special layered structure. Here,the luminescence properties of the Er^3＋/Sm^3＋ co-doped BiOCl phosphors as single-phase phosphors were reported. Upon near ultraviolet excitation（NUV, 380 nm corresponding the ^4 I15/2→ ^4 G11/2 transition of Er^3＋ ions）, the phosphors exhibit the efficient characteristic emissions of Er^3＋ and Sm^3＋ ions simultaneously. The energy transfer（ET） from Er^3＋ to Sm^3＋ ions in the layered crystals has been validated by the variation of emission intensities and decay lifetimes respectively, which is ascribed to be a dipoledipole interaction. By virtue of the ET behavior and increasing Sm^3＋ ion concentration, the enhancing emission intensity of Sm^3＋ and the tunability of emission color from yellowish-green（0.318, 0.420） to white（0.343, 0.347） are realized. The results of our work indicate that the Er^3＋/Sm^3＋ co-doped BiOCI phosphor has a promising application serving as single component white emitting phosphors for NUV excited WLEDs.

关键词： BiOCl Er^3+ Sm^3+ Color tunable Photoluminescence Energy transfer

止裂孔-疲劳裂纹尖端相对位置对工业纯铁DT4C抗疲劳性能的影响

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锻压技术 2024年第2期49卷 265-274页

作者：刘荣伟黄志国李艳艳孙立强宋劲松河北石油职业技术大学工业技术中心河北承德067000 河北石油职业技术大学机械工程系河北承德067000

止裂孔是金属结构件疲劳延寿的重要方法之一,但其对疲劳裂纹扩展速率及疲劳寿命的影响规律复杂多变,以工业纯铁DT4C金属板材为例,采用扩展紧凑拉伸试样(E-CT)研究了止裂孔相对疲劳裂纹尖端的不同位置(即裂纹尖端前沿材料切除量分别为0.3... 详细信息

止裂孔是金属结构件疲劳延寿的重要方法之一,但其对疲劳裂纹扩展速率及疲劳寿命的影响规律复杂多变,以工业纯铁DT4C金属板材为例,采用扩展紧凑拉伸试样(E-CT)研究了止裂孔相对疲劳裂纹尖端的不同位置(即裂纹尖端前沿材料切除量分别为0.3、0.6和0.9 mm)对含裂纹试件的疲劳寿命和裂纹扩展速率的影响规律。结果表明:由于在疲劳裂纹扩展过程中裂纹尖端沿厚度方向上扩展速率的差异及裂尖塑性区的存在,裂纹尖端前沿材料切除量对止裂孔的延寿作用具有重要影响,且影响程度差别较大。在相同疲劳载荷和应力比近似为0的情况下,裂纹尖端前沿材料切除量为0.6 mm时,试样的疲劳裂纹扩展速率和疲劳寿命改善最为明显,与常规试样相比疲劳寿命增加了2倍以上。

关键词：止裂孔裂纹尖端疲劳裂纹扩展速率疲劳寿命裂纹尖端塑性区