流动注射化学发光法测定盐酸米托蒽醌

在酸性条件下，甲醛与高锰酸钾能够产生较弱的化学发光，而盐酸米托蒽醌能够大大地增强该化学发光强度．在一定浓度范围内，增加的发光强度与盐酸米托蒽醌的浓度呈良好的线性关系．由此建立了一种测定盐酸米托蒽醌的流动注射化学发光新方法，方法的检出限为6．4μg／L（IUPAC），线性范围为0.01～1.0mg／L，对0.5mg／L盐酸米托蒽醌平行测定11次，其相对标准偏差为2．8％．

镧系离子掺杂的AgY(MoO4)2上转换荧光粉的形貌调控及其温敏性研究

在没有添加剂的条件下,仅通过一步水热法成功制备出AgY(MoO4)2:Yb^3+/Er^3+上转换微米材料,探讨了发光粒子浓度与发光强度关系和上转换发光机理.在980 nm近红外光激发下,AgY(MoO4)2:Yb^3+/Er^3+荧光粉的绿色发射(526 nm,551 nm)在298 K至573 K的温度区间展现了良好的温度依赖性,并在498 K处得出最大的灵敏度为0.01685 K^-1.表明该荧光材料在光学测温技术中具有潜在应用,可作为高温、高灵敏度的光学温度传感器.

On the Bonding Nature of Noble Gas Compounds MRg^(+) and MRgF(M=Co,Rh,Ir;Rg=Ar,Kr,Xe)

The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and thermodynamics properties of these compounds.A series of theoretical methods on the basis of wavefunction analysis,including natural bond orbitals,atoms in molecules,electron localization function,and energy decomposition analysis,were performed to explore bonding nature of the M-Rg and Rg-F bonds.These bonds are mainly noncovalent,the metal weakly interacts with Rg in MRg^(+),but their interaction is much stronger in MRg F.The neutral molecule MRg F can be well described by the Lewis structure[MRg]^(+)F^(-).

关于水热合成AgY(MoO_(4))2:Yb^(3+),Ho^(3+),Tm^(3+)荧光粉的上转换白光研究

在无任何添加剂作用下仅通过简单水热法成功制备了AgY(MoO_(4))2:Ln^(3+)(Ln=Yb^(3+),Ho^(3+),Tm^(3+))荧光粉。在980 nm近红外激发下,研究了荧光粉的上转换发光性质与能量传递机制,AgY(MoO_(4))2:Yb^(3+)/Ho^(3+)的上转换发射光谱由绿色发射(539 nm)和红色发射(658 nm)组成,AgY(MoO_(4))2:Yb^(3+)/Tm^(3+)的上转换发射光谱主要为蓝色发射(475 nm)。当三掺Yb^(3+)/Ho^(3+)/Tm^(3+)离子时,成功制得较为理想的白色上转换荧光粉(0.3345,0.3309),与国际标准色度坐标值相接近(0.33,0.33),可能具有生物医学探针等潜在应用。

o-C8 Carbon: a New Allotrope of Superhard Carbon

An orthonormal crystal of carbon with PMMA space group(o-C8)was found to be a stable superhard carbon allotrope by particle swarm optimization algorithm and density functional calculations.The phonon spectrum calculations demonstrate that the o-C8 carbon phase is dynamically stable.The volume compression calculations show that it is highly incompressible,with bulk modulus of 298.6 GPa.The calculations demonstrate that it is a low-density superhard material with density of 2.993 g/cm^3 and Vickers hardness of 82.4 GPa.

Surface,Size and Thermal Effects in Alkali Metal with Core-Electron Binding-Energy Shifts

Consistency between density functional theory calculations and X-ray photoelectron spectroscopy measurements confirms our predications on the undercoordination-induced local bond relaxation and core level shift of alkali metal,which determine the surface,size and thermal properties of materials.Zone-resolved photoelectron spectroscopyanalysis method and bond order-length-strength theory can be utilized to quantify the physical parameters regarding bonding identities and electronic property of metal surfaces,which allows for the study of the core-electron binding-energy shifts in alkali metals.By employing these methods and first principle calculation in this work,we can obtain the information of bond and atomic cohesive energy of under-coordinated atoms at the alkali metal surface.In addition,the effect of size and temperature towards the binding-energy in the surface region can be seen from the view point of Hamiltonian perturbation by atomic relaxation with atomic bonding.