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Up-conversion emissions of Er^(3+)-Yb^(3+) codoped Al_2O_3 nanoparticles by the arc discharge synthesis method

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Science china({1.,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DOnG Bin1. CAO BaoSheng1. FEnG ZhiQing1. wang XingJun2, LI ChengRen3 & HUA Ruinian4 1.{1. of Science, Dalian nationalities University, Dalian 1.6600, china 2 {1. of electronics engineering and Computer Science, Peking University, Beijing 1.0871. china 3 College of physics and electronic Technology, Liaoning normal University, Dalian 1.6029, china 4 College of Life Science, Dalian nationalities University, Dalian 1.6600, china 1. school of Science Dalian Nationalities University Dalian 116600 China 2. school of {1.s engineering and Computer Science Peking University Beijing 100871 China 3. College of physics and {1. Technology Liaoning Normal University Dalian 116029 China 4. College of Life Science Dalian Nationalities University Dalian 116600 China

The Er3+-Yb3+ codoped Al2O3 nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 547 and 677 nm, corresponding respectively to the 2H1./2→4I1./2, 4S3/2→4I1./2 and 4 F9/2→4I1./2 transitions of Er3+, were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3Al5O1. and α-(Al,Er,Yb)2O3 phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4I1./2+a photon→4F7/2 and ET (III) of 2F5/2(Yb3+)+4I1./2(Er3+)→2F7/2(Yb3+)+4F7/2(Er3+) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3+-Yb3+ codoped Al2O3 arc discharge synthesis

Wavelength and oscillator strength of dipole transition 1.^22p—1.^2nd for Mn^(22+) ion

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Science china({1.,Mechanics & Astronomy) 2008年第11期51卷 1633-1637页

作者： wang ZhiWen, wang Yanan, HU MuHong, LI XinRu & LIU Ying school of physics and electronic Technology, Liaoning normal University, Dalian 1.6029, china 1. school of {1. and electronic Technology Liaoning Normal University Dalian 116029 China

The transition energies, wavelengths and dipole oscillator strengths of 1.22p-1.2nd (3≤n≤9) for Mn22+ ion are calculated. The fine structure splittings of 1.2nd (n≤9) states for this ion are also evaluated. In calculating energy, the higher-order relativistic contribution is estimated under a hydrogenic approximation. The quantum defect of Rydberg series 1.2nd is determined according to the quantum defect theory. The results obtained in this paper excellently agree with the experi-mental data available in literatures.

关键词： Mn22+ ion transition energy fine structure splitting quantum defect oscillator strength

A Tri-Section Stepped Impedance Bandpass Filter with Harmonic Suppression

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A Tri-Section Stepped Impedance Bandpass Filter with Harmoni...

Parallel Scheduling Algorithms Investigation of Support Strict Resource Reservation from Grid

2007 7th International Conference on ASIC electronic Version(ASICOn 2007)

作者： Yunxiu wang1 2 Bing-Zhong wang1 Jianpeng wang1 1 Institute of Applied physics University of electronic Science and Technology of china Chengdu 610054 P.R.china 2 school of physics and electronic Information china-West normal University nanchong 637002 P.R.china

A compact microstrip bandpass filter with harmonic suppression is presented in this *** filter is composed of two tri-section stepped impedance resonators cascaded and two end-open L-shaped microstrip lines for the input and output feed *** harmonic suppression of the bandpass filter may be realized by choosing proper lengths for the L-shaped microstrip lines and proper impedance ratios of the stepped impedance *** filter has been investigated *** results show that the second-order harmonic response is effectively suppressed,and the rejection level is kept below-1.dB.

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Parallel Scheduling Algorithms Investigation of Support Stri...

201. 3rd IEEE International Conference on Information Management and engineering(ICIME 201.)

作者： Jun Chen 1.1.school of {1. and electronic engineering Qujing normal University Qujing Yunnan P.R.china (65501.) Bo Li 2 Erfei wang 2.school of Information Science and engineering Yunnan University Kunming Yunnan P.R.china (650091.

This paper studies resource reservation mechanisms in the strict parallel computing grid,and proposed to support the parallel strict resource reservation request scheduling model and algorithms,FCFS and EASY backfill analysis of two important parallel scheduling algorithm,given four parallel scheduling algorithms supporting resource *** results of four algorithms of resource utilization,job bounded slowdown factor and the success rate of Advanced Reservation（AR） jobs were *** results show that the EASY backfill + firstfit algorithm can ensure QoS of AR jobs while taking into account the performance of good non-AR jobs.

关键词： grid computing strict resource reservation parallel scheduling algorithm

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太阳能固体吸附式制冰机间隙制冷现象的研究

太阳能学报 2004年第4期25卷 473-478页

作者：李明王如竹王六玲云南师范大学物理与电子信息学院昆明650092 上海交通大学制冷与低温工程研究所上海200030

对整体无阀结构太阳能固体吸附式制冰机在真实环境工况下进行实验研究,得出在外界云层影响下太阳能固体吸附式制冰机的性能特性。采用经实验验证后的传热传质模型,分析了太阳能制冰机受外界云层影响下所表现出的间隙制冷效果。实验与理... 详细信息

对整体无阀结构太阳能固体吸附式制冰机在真实环境工况下进行实验研究,得出在外界云层影响下太阳能固体吸附式制冰机的性能特性。采用经实验验证后的传热传质模型,分析了太阳能制冰机受外界云层影响下所表现出的间隙制冷效果。实验与理论两方面的工作为太阳能固体吸附式制冰机的合理应用提供了区域气候选择的依据,为科学分析太阳能制冰机性能提供了客观的基础。

关键词：太阳能固体吸附间隙制冷云层影响

广义Hénon映像的广义超混沌同步的电路实验

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深圳大学学报（理工版） 2005年第1期22卷 31-36页

作者：王琳赵明彭建华深圳大学理学院

利用电子线路实验,以具有超混沌特性的广义H啨non映像为例,提出一种构造广义超混沌同步系统的方法.实验结果与理论数值分析基本一致,实验证明该方法有效可行,且其广义超混沌同步系统具有一定的鲁棒性.

关键词：广义超混沌同步线性变换电路实验

The birhythmicity increases the diversity of p53 oscillation induced by DnA damage

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Chinese physics B 2017年第12期26卷 68-75页

作者：王道光周春红张小鹏 national Laboratory of Solid State Microstructure and Department of physics Nanjing University Nanjing 210093 China school of {1. and electronic engineering Jiangsu Normal University Xuzhou 221116 China Kuang Yaming Honors school Nanjing University Nanjing 210023 China

The tumor suppressor p53 mediates the cellular response to various stresses. It was experimentally shown that the concentration of p53 can show oscillations with short or long periods upon DnA damage. The underlying mechanism for this phenomenon is still not fully understood. Here, we construct a network model comprising the ATM-p53-Wip1.and p53-Mdm2 negative feedback loops and ATM autoactivation. We recapitulate the typical features of p53 oscillations including p53 birhythmicity. We show the dependence of p53 birhythmicity on various factors such as the phosphorylation status of ATM. We also perform stochastic simulation and find the noise-induced transitions between two modes of p53 oscillation, which increases the p53 variability in both the amplitude and period. These results suggest that p53 birhythmicity enhances the responsiveness of p53 network, which may facilitate its tumor suppressive function.

关键词： p53 birhythmicity oscillation

基于塔姆激元-表面等离极化激元混合模式的单缝加凹槽纳米结构的增强透射

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物理学报 2018年第10期67卷 179-186页

作者：祁云平周培阳张雪伟严春满王向贤西北师范大学物理与电子工程学院甘肃省智能信息技术与应用工程研究中心兰州730070 兰州理工大学理学院兰州730050

金属单缝纳米结构因为结构简单、易于集成,常用在基于表面等离极化激元(surface plasmon polaritons,SPPs)的纳米结构中构建光源.但是,金属亚波长单缝结构一直存在透射率低的问题,如何提高其透射率一直是研究的重点.为了更好地提高金属... 详细信息

金属单缝纳米结构因为结构简单、易于集成,常用在基于表面等离极化激元(surface plasmon polaritons,SPPs)的纳米结构中构建光源.但是,金属亚波长单缝结构一直存在透射率低的问题,如何提高其透射率一直是研究的重点.为了更好地提高金属亚波长单缝的透射率,本文对之前文献提出的分布式布拉格反射镜(distributed bragg reflector,DBR)和金属银薄膜纳米缝结构进行改进,在金属银薄膜两侧设计凹槽.当TM偏振光由DBR侧入射至DBR-银纳米缝结构时,DBR-银膜界面上和银膜入射侧凹槽一起激发的塔姆激元(Tamm plasmon polaritons,TPPs)和SPPs,以及纳米缝和银膜出射侧凹槽对的SPPs同时激发,利用凹槽激发的SPPs和银膜表面处的TPPs-SPPs混合模式的干涉相长耦合作用,通过塔姆激元的局域场增强效应和两侧凹槽与单纳米缝的干涉相长耦合作用进一步提高了表面等离极化激元模式的激发效率,再加上纳米缝中的类法布里-珀罗腔共振效应,使纳米缝的透射率得到增强.本文采用有限元方法研究了DBR-银纳米缝结构上单纳米缝加凹槽的透射特性.经过一系列参数优化,使DBR-银纳米缝凹槽结构的最大透射率增加到0.22,相对于TiO_2-银纳米缝结构的透射率(0.01.提高了22倍,比文献[23]得到的最大透射率0.1.6有所提高.研究结果在纳米光源设计、光子集成电路和光学信号传输等相关领域具有一定的应用价值.

关键词：光学异常透射塔姆激元表面等离极化激元类法布里-珀罗腔共振

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人体阻抗模型与人体域通信信道特性分析

微波学报 2010年第S2期26卷 321-324页

作者：阮方鸣孙思扬陈旋周峰王晓璐杨乘高攸纲贵州师范大学物理与电子学院贵阳550001 北京邮电大学电子工程学院北京100876 工业与信息化部通信计量中心北京100191

基于人体柱体模型分析了输入阻抗与人体形状大小的关系,就人体信道的频率传输特性进行了讨论,在3～5GHz的频率范围内,人体对传输信号具有良好的响应。考虑到多径传输环境下的信噪比和误码率,采用二相相移键控(BPSK)的调制方式,对人体域... 详细信息

基于人体柱体模型分析了输入阻抗与人体形状大小的关系,就人体信道的频率传输特性进行了讨论,在3～5GHz的频率范围内,人体对传输信号具有良好的响应。考虑到多径传输环境下的信噪比和误码率,采用二相相移键控(BPSK)的调制方式,对人体域无线传输信道具有更好的性能。

关键词：人体阻抗频率响应人体域网络