Tb0.3Dy0.7(Fe0.9T0.1)1.95合金的结构、自旋重取向和穆斯堡尔谱

系统研究了室温下Tb_0.3Dy_0.7(Fe_0.9T_0.1)_1.95(过渡金属元素T=Mn，Fe，Co，B，Al，Ga)合金中ⅢA族金属和过渡金属元素T替代Fe对结构、自旋重取向和穆斯堡尔谱的影响.结果发现，不同金属T替代Fe，Tb_0.3Dy_0.7(Fe_0.9T_0.1)_1.95，合金具有相同的MgCu₂型立方Laves相结构；Al，Ga替代使Tb_0.3Dy_0.7(Fe_0.9T_0.1)_1.95合金的易磁化方向在{110}面逐渐偏离了立方晶体的主对称轴，即自旋重取向，B，Mn，Co替代未使易磁化轴发生明显转动；Al，Ga元素替代使超精细场H_hf略有下降，B，Mn替代对超精细场H_hf的影响不大，而Co元素替代使超精细场H_hf有较大增加；所有元素替代使同质异能移IS有所增加；B，Al，Ga和Mn替代使四极劈裂Q_s增加，而Co替代使四极劈裂Q_s下降. 关键词： 立方Laves相 自旋重取向 穆斯堡尔谱     

强碱性阴离子交换树脂分离富集土壤中的钼

研究了以强碱性阴离子交换树脂为固定相的离子交换色谱法分离富集土壤中钼,实现了钼与其他常见金属元素离子的选择性分离,富集在色谱柱上的钼以0.5mol.L^-1NH4NO3＋2mol.L^-1HNO3洗脱并用富氧火焰原子吸收光谱法进行测定,钼的回收率为99%—101.3%。     

Tb$lt;sub$gt;0.3$lt;/sub$gt;Dy$lt;sub$gt;0.6$lt;/sub$gt;Pr$lt;sub$gt;0.1$lt;/sub$gt;(Fe$lt;sub$gt;1-$lt;i$gt;x$lt;/i$gt;$lt;/sub$gt;Al$lt;sub$gt;$lt;i$gt;x$lt;/i$gt;$lt;/sub$gt;)$lt;sub$gt;1.95$lt;/sub$gt;合金的磁性、磁致伸缩和穆斯堡尔谱研究

系统研究了室温下Tb_0.3Dy_0.6Pr_0.1（Fe_1-xAl_x）_1.95 （x=0.05,0.1,0.15,0.2,0.25,0.3）合金中元素Al替代Fe对结构、磁性、磁致伸缩性能和自旋重取向的影响.测量结果发现,x<0.2时Tb_0.3Dy_0.6Pr_0.1（Fe_1-xAl_x）_1.95合金基本上是纯的单相,x=0.2时出现其他杂相,杂相随Al替代量的增加不断增多.随Al替代量x的增加,点阵常数a接近于线性增大,Curie温度T_C逐渐下降,而矫顽力H_c急剧下降.振动样品磁强计（VSM）测量发现,磁化强度M随Al替代量x的变化较为复杂.VSM计和磁致伸缩效应测量共同表明,少量Al的替代有利于降低磁晶各向异性,而且随着Al替代量x的增多磁致伸缩系数快速减小,x>0.15时巨磁致伸缩效应消失.穆斯堡尔效应研究发现,随Al含量的增加Tb_0.3Dy_0.6Pr_0.1（Fe_1-xAl_x）_1.95合金中易磁化轴可能在{110}面逐渐偏离了立方晶体的主对称轴,发生自旋重取向,从而引起合金宏观磁性、磁致伸缩性能的变化. 关键词： 磁致伸缩 立方Laves相 自旋重取向 穆斯堡尔谱     

超高压水的分子动力学模拟

 采用平衡分子动力学（EMD）方法,模拟研究了温度范围为243~348 K、压强范围为0.1~400 MPa条件下水的热力学性质、结构和动力学性质,模拟结果与实验值吻合较好。模拟结果表明,随着压强的增大,水分子间的氢键作用增强,扩散系数减小;随着温度的升高,水分子间的氢键作用减弱,有序程度下降,扩散系数增大。但在过冷水中,扩散系数随压强的增大有增加的趋势。     

1-苯并噻唑基-吡唑啉类荧光化合物的合成及其荧光光谱

合成了几种苯并噻唑基 -吡唑啉类化合物 ,经红外吸收光谱和荧光发射光谱测定 ,此类化合物具有一定的荧光性 ,其荧光强度的大小与衍生物中不同的取代基有关。     

Synthesis,reactivity and structural characterization of lanthanide hydroxides stabilized by a carbon-bridged bis(phenolate) ligand

The synthesis of lanthanide hydroxo complexes stabilized by a carbon-bridged bis(phenolate) ligand 2,2’-methylene-bis(6-tert-butyl-4-methylphenoxo) (MBMP²⁻) was described, and their reactivity toward phenyl isocyanate was explored. Reactions of (MBMP)Ln(C₅H₅)(THF)₂ with a molar equiv. of water in THF at −78 °C afforded the bis(phenolate) lanthanide hydroxides as dimers [{(MBMP)Ln(μ-OH)(THF)₂}₂] [Ln = Nd (1), Yb (2)] in high yields. Complexes 1 and 2 reacted with phenyl isocyanate in THF, after workup, to give the desired O−H addition products, [(MBMP)Ln(μ-η¹:η²-O₂CNHPh)(THF)₂]₂ [Ln = Nd (3), Yb (4)] in excellent isolated yields. These complexes were well characterized, and the molecular structures of complexes 2 to 4 were determined by X-ray crystallography. The ytterbium atom in complex 2 is coordinated to six oxygen atoms to form a distorted octahedral geometry, whereas each metal center in complexes 3 and 4 is seven-coordinated, and the coordination geometry can be best described as a distorted pentagonal bipyramid.     

咔唑衍生物的固相合成及其双光子吸收和光存储应用

以N-乙基咔唑为原料,通过室温固相化学反应改进合成了2种双光子吸收材料(咔唑类衍生物2, 8-二[2'-(吡啶-4"-基)乙烯基]-5-乙基咔唑(L1),2, 8-二[2'-(吡啶-2"-基)乙烯基]-5-乙基咔唑(L2),其结构经¹H NMR,IR和MS确证,利用Z-扫描技术,测试了其纳秒下的双光子吸收截面为6 210和5 590 GM (1 GM = 1 ´ 10 ^-50 cm ⁴ · s · photon ^-1),用820 nm的飞秒单脉冲激光作为写入激光对存储介质进行双光子光漂白,对其作为三维光存储材料作了初步的探索。     

Increasing structure dimensionality of copper(I) complexes by varying the flexible thioether ligand geometry and counteranions

This work focuses on the systematic investigation of the influences of pyrimidine-based thioether ligand geometries and counteranions on the overall molecular architectures. A N-containing heterocyclic dithioether ligand 2,6-bis(2-pyrimidinesulfanylmethyl)pyridine (L1) and three structurally related isomeric bis(2-pyrimidinesulfanylmethyl)benzene (L2-L4) ligands have been prepared. On the basis of the self-assembly of CuX (X = I, Br, Cl, SCN, or CN) and the four structurally related flexible dithioether ligands, we have synthesized and characterized 10 new metal-organic entities, Cu4(L1)2I4 1, Cu4(L1)2Br4 2, [Cu2(L2)2I2.CH3CN]n 3, [Cu(L3)I]n 4, [Cu(L3)Br]n 5, [Cu(L3)CN]n 6, [Cu(L4)CN]n 7, [Cu2(L4)I2]n 8, [Cu2(L4)(SCN)2]n 9, and [[Cu6I5(L4)3](BF4).H2O]n 10, by elemental analyses, IR spectroscopy, and X-ray crystallography. Single-crystal X-ray analyses show that the 10 Cu(I) complexes possess an increasing dimensionality from 0D (1 and 2) to 1D (3-5) to 2D (6-9) to 3D (10), which indicates that the ligand geometry takes an essential role in the framework formation of the Cu(I) complexes. The influence of counteranions and pi-pi weak interactions on the formation and dimensionality of these coordination polymers has also been explored. In addition, the photoluminescence properties of Cu(I) coordination polymers 4-10 in the solid state have been studied.     

高中化学校本课程的开发与实施进展

介绍了高中化学校本课程的开发和实施进展,综述了化学校本课程的活动方式,总结了化学校本课程的实施特点,初步探讨了校本课程的开发和实施过程中存在的问题,提出跨学科课程整合、校际合作和职业化课程开发是今后我国化学校本课程开发的新方向。     

铁电存储器中高能质子引发的单粒子功能中断效应实验研究

利用中国原子能科学研究院的中高能质子实验平台,针对两款商用铁电存储器开展了中高能质子单粒子效应实验研究,发现其中一款器件在质子辐照下发生了单粒子翻转和单粒子功能中断.本文主要针对单粒子功能中断效应展开了后续实验研究.首先通过改变质子能量对器件进行辐照,发现单粒子功能中断截面随质子能量的提高而增加.为进一步研究器件发生单粒子功能中断的机理,利用激光微束平台开展了辅助实验,对铁电存储器的单粒子功能中断效应的敏感区域进行了定位,最后发现铁电存储器单粒子功能中断是由器件外围电路发生的微锁定导致的.