Ⅱ-Ⅵ族稀磁半导体Cd_(1-x)Mn_xTe/Cd_(1-y)Mn_yTe超晶格的光调制反射谱的研究

本文报道用分子束外延（ＭＢＥ）技术生长的Ｃｄ１－ｘＭｎｘＴｅ／Ｃｄ１－ｙＭｎｙＴｅ超晶格样品在８０Ｋ下的光调制反射谱实验结果。观测到１１Ｈ、２２Ｈ、３３Ｈ和１１Ｌ等激子跃迁结构。计及晶格失配导致的应力效应，对子能级结构进行了理论计算。实验结果与理论计算符合较好。     

La—Ce—Mn系钙钛矿型催化剂性能研究

采用共沉淀法制得了Ｃｅ＾４＋，部分取代Ｌａ＾３＋的Ｌａ１－ｘＣｅｘＭｎＯ３钙钛矿型催化剂，实验结果表明，随Ｃｅ＾４＋取代量ｘ的增大，Ｌａ１－ｘＣｅｘＭｎＯ３催化剂越易被还原，其还原活化逐渐降低，对于ＣＯ，ＣＨ４氧化的反应其活性有一最大值，ＣＯ反应ｘ的０．４，ＣＨ４反应ｘ为０．２，这是由于随ｘ值的增大，催化剂晶格缺陷增多，晶格氧的化学势增大，以及ＣｅＯ２杂质相的协同作用的结果，在ＣＯ氧化和用Ｈ２还原     

5—Meng氧基—3,4—二取代丁烯内酯NMR的研究

报道了光学纯５－（１－Ｍｅｎｇ氧基）－３，４－二取代２（５Ｈ）－呋喃酮的＾１Ｈ ＮＭＲ和＾１３Ｃ ＮＭＲ数据，研究了不同取代基对结构以及核磁参数的影响。     

合成抗孕酮新药RU-486中间体3,3-乙撑二氧-5α,10α及5β,10β-环氧-Δ~(9(11))-雌烯-17α(1-丙炔基)-17β-羟基的~1H和~(13)C NMR谱线全归属

用１Ｄ及２ＤＮＭＲ技术（ＣＯＳＹ，ＴＯＣＳＹ，ＨＭＱＣ及ＨＭＢＣ）归属了合成抗孕酮新药ＲＵ－４８６中间体３，３乙撑二氧５α，１０α及５β，１０β环氧－Δ９（１１），雌烯１７α（１－丙炔基）１７β羟基的１Ｈ和１３ＣＮＭＲ谱线．     

槲皮素—3—鼠李糖—（6—对羟基反式桂皮酰）葡萄糖甙1—2连接的NMR谱 …

用２Ｄ ＮＭＲ技术研究了从银杏叶提取物中分离的一个黄酮双糖甙［槲皮素－３－鼠李糖－（６－对羟基反式桂皮酰）葡萄糖甙］的结构,对鼠李糖部分的＾１Ｈ ＮＭＲ,＾１３Ｃ ＮＭＲ化学位移进行了归属。＾１３Ｃ化学位移和＾１Ｈ ＮＯＥ相关性都证明鼠李糖为１″－２″连接。     

a－Si：H／a－SiC＿x：H超晶格的界面特性

报道等离子体化学汽相沉积法制备的ａ－Ｓｉ：Ｈ／ａ－ＳｉＣ：Ｈ超晶格的蓝移现象，用小角度Ｘ射线衍射确定超晶格的界面陡度。通过红外测量和常数光电流测量发现，超晶格界面附近存在较高浓度的Ｈ和较多的Ｓｉ－Ｃ键，界面Ｈ的热稳定性较差，界面缺陷态密度为１．２×１０￣（１１）ｃｍ￣（－２）。     

2：17型结构Gd—Fe—Co—Ga化合物的结构与磁性

用电弧熔炼的方法制备了Ｇｄ２（Ｆｅ１－ｘＣｏｘ）１５Ｇａ２（０≤ｘ≤１０）和Ｇｄ２（Ｆｅ０８Ｃｏ０２）１７－ｙＧａｙ（０≤ｙ≤８）化合物，通过Ｘ射线衍射和磁性测量手段研究了它们的结构和磁性．实验结果表明它们都是２∶１７型结构的单相化合物．Ｇｄ２（Ｆｅ１－ｘＣｏｘ）１５Ｇａ２的单胞体积Ｖ随Ｃｏ含量的增加单调下降，而居里温度ＴＣ单调上升，１５Ｋ下的饱和磁化强度Ｍｓ随Ｃｏ含量的增加开始时略有增大，在ｘ＝０２时出现极大值，然后单调下降；对Ｇｄ２（Ｆｅ０８Ｃｏ０２）１７－ｙＧａｙ的样品，随Ｇａ含量的增加单胞体积增加，居里温度和饱和磁化强度单调下降．用Ｃｏ替代Ｆｅ，或用Ｇａ替代Ｆｅ和Ｃｏ都能导致Ｆｅ或Ｃｏ次晶格出现室温单轴各向异性，这可能与Ｇａ原子的择优占位有关．     

a-Si:H/a-SiCx:H超晶格的界面特性

报道等离子体化学汽相沉积法制备的ａ－Ｓｉ：Ｈ／ａ－ＳｉＣ：Ｈ超晶格的蓝移现象，用小角度Ｘ射线衍射确定超晶格的界面陡度。通过红外测量和常数光电流测量发现，超晶格界面附近存在较高浓度的Ｈ和较多的Ｓｉ－Ｃ键，界面Ｈ的热稳定性较差，界面缺陷态密度为１．２×１０^１１ｃｍ^-2。 关键词：     

质子射频场照射对碳—13自旋晶格弛豫的影响

用推广的Ｓｏｌｏｍｏｎ方程描述了＾１Ｈ通道加上射频场的＾１３Ｃ自旋晶格弛豫，分析表明在＾１Ｈ射频照射下＾１３Ｃ自旋晶格弛豫通常是一个三指数过程，但是在一些实验条件下可以变为单指数的；数值计算给出了满足Ｔ１＾ｃ＜Ｔ１＾Ｈ和满足Ｔ１＾ｃ＞Ｔ１＾Ｈ的＾１３Ｃ自旋晶格弛豫过程的明显差别，并显示了不同射频场强度的影响，实验观测了固体Ｌ－缬氨酸的甲基＾１３Ｃ自旋晶格弛豫，所得结果与理论分析很好符合。     

GeO2—Sb2O3—K2O玻璃空芯光纤材料的光学特性研究

系统地研究了传输ＣＯ２激光用的新型光材料ＧｅＯ２－Ｓｂ２Ｏ３－Ｋ２Ｏ玻璃空芯光纤的光学特性。通过理论计算，得到了该材料ｎｒ＜１的波长范围，消光系数Ｋ和损耗数ａ，通过工艺和材料的选择，使ａ理论值达到０．０５ｄＢ／ｍ。同时讨论了ＨＥ１１，ＴＭ０１，ＴＥ０１模式损耗和频率的关系。     

高组分稀磁半导体Cd1-xMnxTe/CdTe超晶格的荧光谱研究

报道用分子束外延(MBE)技术生长的x=0.4,0.8的高组分稀磁半导体Cd1-xMnxTe/CdTe超晶格低温和室温荧光谱研究结果.基态激子跃迁能级荧光谱实验结果显示高组分超晶格中具有高量子效率和高质量光发射.对激子能级随温度的变化进行了详细研究,给出激子跃迁能量的温度系数.激子能级线型的展宽随温度变化关系可用激子-纵向光学声子耦合模型解释.与光调制反射谱实验结果进行了比较.     

Effects of Cd compensation on the photoluminescence of Cd1-xZnxTe single crystals grown by the modified Bridgman method

In order to deal with the phenomenon of Cd evaporation during the growth of Cd_1-xZn_xTe (x=0.1) crystals, Cd compensation was adopted during the growth by adding excess Cd into the raw materials. Photoluminescence (PL) spectra were used to investigate the effects of Cd compensation on the properties of Cd_1-xZn_xTe. A free exciton (FE) peak appeared in the near band-edge region after Cd compensation, which indicated that the concentration of Cd vacancies (V_Cd) was reduced in Cd_1-xZn_xTe crystals by Cd compensation. The donor–acceptor pair (DAP) peak became dominant in the PL spectrum and its first and second order phonon replica could also be easily identified after Cd compensation, which was only a weak hump in the case of Cd_1-xZn_xTe crystals without Cd compensation. It possibly meant that impurities of Al and In were released from the V_Cd-related complexes. In addition, the deep energy level transition D peak, decreased obviously after Cd compensation, which confirmed that Cd compensation could reduce the dislocation density effectively. PACS 71.20.Nr; 71.55.Gs; 78.55.-m     

The quadrupole moments of Cd and Zn isotopes - an apology

In 2010 we presented an update of the nuclear quadrupole moments (Q) for the Cd and Zn isotopes, based essentially on straightforward density functional (DF) calculations (H. Haas and J.G. Correia, Hyperfine Interact 198, 133–137 (2010)). It has been apparent for some years that the standard DF procedure obviously fails, however, to reproduce the known electric-field gradient (EFG) for various systems, typical cases being Cu₂O, As and Sb, and the solid halogens. Recently a cure for this deficiency has been found in the hybrid DF technique. This method is now applied to solid Cd and Zn, and the resultant quadrupole moments are about 15 % smaller than in our earlier report. Also nuclear systematics, using the recently revised values of Q for the long-lived 11/2 isomers in¹¹¹Cd to¹²⁹Cd, together with earlier PAD data for^107,109Cd, leads to the same conclusion. In addition, EFG calculations for the cadmium dimethyl molecule further support the new values: Q(¹¹¹Cd, 5/2⁺) = .683(20) b, Q(⁶⁷Zn, gs) = .132(5) b. This implies, that the value for the atomic EFG in the \(^{3}\textit {P}_{1}\) state of Zn must be revised, as it has been for Cd.     

石墨炉原子吸收光谱法测定水处理剂中微量铅和镉

本文研究了石墨炉原子吸收光谱法测定水处理剂聚合氯化铝中铅、镉含量的适宜条件。用氘灯校正背景 ,磷酸二氢铵做基体改进剂 ,省去了冗长的前处理过程。在测定条件下 ,铅的检测限为 0 .6 5μg· L- 1 ,线性范围 0～ 5 0 μg·L- 1 ;镉的检测限为 0 .12 μg· L- 1 ,线性范围 0～ 2 0 μg·L- 1 ;回收率在 90 %～ 110 %之间。本方法具有准确、快速、简便之优点 ,用于实验样品的测定 ,结果令人满意。     

偶偶Cd同位素核的形变HF态及负宇称带研究

将具有正宇称的轨道空间扩大到包含具有负宇称的1h_11/2轨道,采用修正的表面δ相互作用(MSDI),对¹⁰⁴Cd,¹⁰⁶Cd,¹⁰⁸Cd,¹¹⁰Cd,¹¹²Cd,¹¹⁴Cd和¹¹⁶Cd等7个偶偶核作了形变HF计算.得到了基态和一些激发态的解.同时,还用近似角动量投影形变Hartree-Fock(PDHF)方法对¹⁰⁸Cd和¹¹⁰Cd进行了能谱计算,得到其正、负宇称带的解,计算结果与实验谱基本一致.     

Deexcitation of Cd 53P1 atoms in collisions with ground state atoms and molecules

Collisions of excited Cd 5³P₁ atoms were investigated using atomic fluorescence spectroscopy. Cadmium vapor, together with a quenching gas, was irradiated in a quartz fluorescence vessel with Cd 3261 Å resonance radiation and the intensity of the resulting resonance fluorescence was monitored in relation to the gas pressures. The experiments yielded the following cross sections Q₁₀ (in A²) for collisional transfer 5³P₁→5³P₀: CdAr=2×10^?3, CdN₂=8.0, CdH₂=7.0, CdCO=15.6. The cross sections Q for collisional deexcitation to the ground state (quenching) in A² are CdN₂ = 2.6×10^?2, CdH₂ = 11.0, CdCO = 3.4, CdCO₂ = 26.     

Electronic energy transfer from Cd(53P1 to Popop vapor

Quenching of Cd(5³P₁) by POPOP and sensitization of POPOP by Cd(5³P₁) have been investigated in the vapor phase at total pressures of 10^-1 to 10^-2 torr. Quenching of Cd is observed to occur at a rate of 5.9 X 10^-10 cm³/sec and sensitization of POPOP at a rate of 4.2 X 10^-11 cm³/sec. The sensitized fluorescence rate has been found to be consistent with Forsters long-range dipole-dipole mechanism. Selection of a donor for a possible energy transfer, vapor phase, dye laser is discussed.     

Hg1-xCdxTe/Cd1-zZnzTe的X射线反射率及半峰全宽的动力学研究

X射线衍射摇摆曲线的计算机模拟是一种获得材料晶体质量参量的有效方法，其中材料本征摇摆曲线的计算是计算机模拟的基础。用X射线动力学理论计算了Hg1-xCdxTe和Cd1-zZnzTe本征反射率曲线，并研究了组分、膜厚分别对本征反射率和半峰全宽的影响。结果表明Hg1-xCdxTe和Cd1-zZnzTe的本征反射率和半峰全宽与材料组分和厚度有明显的依赖关系，且该依赖关系取决于X射线在材料中的散射和吸收的相对强弱。薄膜的厚度也是直接影响本征摇摆曲线峰形、半峰全宽和反射率的重要因素，当薄膜厚度小于穿透深度时，表征本征反射率曲线的各个参量均与薄膜厚度有直接的关系。对于(333)衍射面，碲镉汞材料厚度大于7μm后，本征反射率和半峰全宽将不再发生明显变化。     

Collective band structures in106,107Cd

Levels in^106,107Cd have been studied with the reactions⁸²Se(³⁰Si, 5-6n)^106,107Cd. The bands observed in the experimental are mostly due to the N=4 and h_11/2 neutron structures.     

水杨醛缩3-羟基-2-萘甲酰肼与Cd2+、Co2+、Cu2+、Zn2+配合物的合成与表征

合成了新型酰腙试剂水杨醛缩3-羟基-2-萘甲酰肼(H2L)及其与Cu2+、Zn2+、Cd2+和Co2+的配合物,通过元素分析、红外光谱、紫外吸收光谱等对配体和配合物进行了表征,确定了其组成和配比,并对配合物的结构进行了推测.