Gd掺杂的Bi系2212相单晶电子状态的X射线光电子能谱研究

利用X射线光电子能谱(XPS)研究了Bi系纯2212相超导单晶和Gd掺杂的2212相绝缘体单晶的电子状态的区别。实验结果表明Gd掺杂引起超导电性的变化是由于D_2p轨道空穴填充引起。本文还对Cu2p_3/2XPS卫星峰与主峰强度之比(I_s/I_m),Bi-O层性质以及Bi系Fermi能级附近态密度的来源等问题进行了讨论。 关键词：     

低通量慢中子对Bi系超导体的辐照效应

本文研究低通量慢中子对Bi系超导体的辐照效应。实验结果表明:(1)Bi系超导体在适量慢中子辐照后,临界电流密度J_c和零电阻温度T_c0都有不同程度提高;(2)低通量慢中子和高通量快中子对Bi系超导体具有相似的辐照效应。 关键词：     

一种橙光磷光铱(Ⅲ)配合物的合成、晶体结构及光电性质研究

采用二氯甲烷为溶剂,无水碳酸钾为缚酸剂,在25℃温和条件下,以2-苯基-4-甲基喹啉铱(III)氯桥二聚体[(4m2pq)2Ir(μ-Cl)2Ir(4m2pq)2]和乙酰丙酮(Hacac)进行配位,反应合成了新型铱(Ⅲ)配合物[(4m2pq)2Ir(acac)]。通过核磁共振氢谱(1H NMR)、碳谱(13C NMR)、X射线单晶衍射等确定分子结构,利用紫外-可见吸收光谱、发射光谱对其光物理性质进行研究。结果表明:(4m2pq)2Ir(acac)的单晶结构属三斜晶系,空间群为P1;(4m2pq)2Ir(acac)在二氯甲烷溶液中呈橙光发射,发射峰为597 nm,磷光寿命0.33μs,量子效率达50.4%。以(4m2pq)2Ir(acac)为客体掺杂在CBP中,制备了结构为ITO/NPB(30 nm)/CBP:(4m2pq)2Ir(acac)(质量分数6%和8%,20 nm)/BCP(10 nm)/Alq3(20 nm)/LiF(1 nm)/Al(150 nm)的橙色磷光有机电致发光器件,器件的最大亮度达到39 667 cd/m2,发射峰位于597 nm,最大电流效率为14.2 cd/A,最大功率效率为8.1 lm/W。     

Color-stable,reduced efficiency roll-off hybrid white organic light emitting diodes with ultra high brightness

High-brightness and color-stable two-wavelength hybrid white organic light emitting diodes (HWOLEDs) with the configuration of indium tin oxide (ITO)/ N, N, N, N-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD): tetrafluoro-tetracyanoqino dimethane (F4-TCNQ)/N,N-di(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB)/ 4,4-N,N-dicarbazolebiphenyl (CBP): iridium (III) diazine complexes (MPPZ) 2 Ir(acac)/NPB/2-methyl-9,10-di(2-naphthyl)anthracene (MADN): p-bis(p-N,N-di-phenyl-aminostyryl)benzene (DSA-ph)/bis(10-hydroxybenzo[h] quino-linato)beryllium complex (Bebq2)/LiF/Al have been fabricated and characterized. The optimal brightness of the device is 69932 cd/m2 at a voltage of 13 V, and the Commission Internationale de l'Eclairage (CIE) chromaticity coordinates are almost constant during a large voltage change of 6-12 V. Furthermore, a current efficiency of 15.3 cd/A at an illumination-relevant brightness of 1000 cd/m2 is obtained, which rolls off slightly to 13.0 cd/A at an ultra high brightness of 50000 cd/m2. We attribute this great performance to wisely selecting an appropriate spacer together with effectively utilizing the combinations of exciton-harvested orange-phosphorescence/blue-fluorescence in the device. Undoubtedly, this is one of the most exciting results in two-wavelength HWOLEDs up to now.     

Online data quality monitoring system at BESⅢ

The online Data Quality Monitoring (DQM) tool plays an important role in the data recording process of HEP experiments. The BESⅢ DQM collects data from the online data flow, reconstructs them with offline reconstruction software and automatically analyzes the reconstructed data with user-defined algorithms. The DQM software is a scalable distributed system. The monitored results are gathered and displayed in various formats, which provides the shifter with current run information that can be used to identify problems quickly. This paper gives an overview of the DQM system at BESⅢ.     

Solutions for a Mode Ⅲ Growing Crack in a Piezoelectric Plane Under Two Kinds of Electric Boundary Conditions ＊

The solutions for a mode Ⅲ crack growing along an arbitrary propagation path in a piezoelectric plane are studied under the impermeable surface condition and the electrical contact surface condition respectively. According to the two kinds of electric boundary conditions, the Hilbert and Riemann boundary value problems in a half-plane including opening smooth arc are obtained from the theoretical analysis. Moreover, the equipollence of the solution formed under these two electric boundaries is proved, and unified solutions for the stress and electric displacement distribution in the crack-tipfield of the piezoelectric plane are achieved.     

流动注射在线分离富集-火焰原子吸收光谱法测定环境水样中Cr(Ⅲ)和Cr(Ⅵ)的形态

采用单阀阴离子和阳离子交换树脂微柱并联 ,两柱交替采样逆向洗脱流动注射在线分离富集环境水样中Cr(Ⅲ )和Cr(Ⅵ ) ,分别用 15 %HNO3和 8%NH4 NO3洗脱 ,火焰原子吸收光谱法直接检测。富集 1min时Cr(Ⅲ )和Cr(Ⅵ )的特征浓度分别为 :1 5 0 μg·L- 1 和 1 39μg·L- 1 ,Cr(Ⅲ )和Cr(Ⅵ )检出限 (3σ)分别为 1 0 3μg·L- 1 和 0 5 4 μg·L- 1 ;相对标准偏差 (10 μg·L- 1 )分别为 :3 4 1%和 1 80 % ,分析样品加标回收率在 93 5 %～ 10 7 5 %之间。     

催化动力学光度法测定痕量铁

论文研究和建立了催化动力学褪色光度法测定痕量Fe(Ⅲ)的新体系,反应介质为盐酸-邻苯二甲酸氢钾(pH2.2)缓冲溶液,催化体系为痕量Fe(Ⅲ)催化过硫酸铵氧化邻甲氧基酚的自聚反应。研究了此反应体系的最佳条件、动力学参数及反应机理,考察了21种干扰离子的影响,建立了一种新型催化动力学光度法测定痕量Fe(Ⅲ)的方法。本法的线性范围0.07～1.1μg·(25mL)~(-1)。方法灵敏度远远高于普通光度法,检出限为5.4×10~(-8)g·L~(-1)。方法应用于自来水、河水、城市污水、豆奶粉和茶叶中痕量Fe(Ⅲ)的测定,相对标准偏差为0.36％～3.4％,标准加入回收率为97.3％～102.7％,结果满意。     

B0d→φK*0极化反常和Bd→φKs CP不对称的研究

在模型Ⅲ下,仅考虑来自于中性规范玻色子H0,H0和A0产生的树图阶味改变中性流的贡献,并利用QCD因子化方法,对B0d→φK(≠)0衰变过程的极化反常和Bd→φKs衰变过程的CP不对称进行了研究,经过计算发现,在147＜|λbsλss|＜165的参数范围内,这两个过程中存在的反常现象能够同时给予解释.