Crystal Structure and Property of Perovskite-Type Oxides Containing Ion Vacancy

Studies on the role of oxygen vacancy in structural change of nonstoichiometric perovskites and a property of oxygen-deficient perovskite-related K₂NiF₄ compounds are reviewed.The structural changes on which the authors focused are cation ordering and lattice distortion. The relationship between the distortion and oxygen vacancy was investigated by comparing the structures of Sr₂(Sr_1-xM_x)TaO_6-d (M = Ca²⁺ and Nd³⁺) solid solutions. It was found that distortion of a perovskite-type lattice decreased with an increasing amount of oxygen vacancies. In order to investigate the relationship between the cation ordering on octahedral sites and oxygen vacancy, structures of stoichiometric Sr_2-xLa_xCo_1-yTa_1+yO₆ and oxygen-deficient Sr_2-xLa_xMg_1-yTa_1+yO_6-d solid solutions were compared. The authors' work reveals that the cation ordering affects the amount of oxygen vacancies in addition to cation charge and size.     

工作用玻璃液体温度计温度修正值的测量不确定度分析

依据JJF1059－1999，利用二等水银湿度计标准装置，分析了工作用玻璃液体温度计温度修正值的测量不确定度。当温度测量点为20℃时，工作用玻璃液体温度计温度修正值的扩展不确定度为0.054℃，当温度测量点为95℃时，工作用玻璃液体温度计温度修正值的扩展不确定度为0.055℃。     

Emission,Emissionslebensdauer und Absorption von [Cr urea6]X3-Einkristallen

Emission and absorption polarization spectra as well as emission lifetimes between room temperature and 5 °K have been measured of [Cr urea₆]X₃ single crystals, where X stands for ClO ₄ ^– , J^–, NO ₃ ^– , Br^–, Cl^–, F^–, and X₃ for JSO ₄ ^3– . The strong temperature dependence of the fluorescence/phosphorescence-ratios, and of the emission lifetimes is discussed. The differences between the spectra as well as the emission lifetimes of the various salts can be attributed to an anion dependent trigonal perturbation.

Die Autoren danken dem Verband der Chemischen Industrie für finanzielle Unterstützung dieser Arbeit.     

茜素红与蛋白质分子Langmuir吸附聚集反应研究

在pH4.3的B-R缓冲体系中,用微相吸附-光谱修正技术[1]研究了茜素红(ARS)与牛血清白蛋白(BSA)、人血清白蛋白(HSA)的结合反应。其吸附结合常数分别为:KBSA-ARS=3.950×104,KHSA-ARS=4.377×104。染料与蛋白的最大结合数分别为NARS∶NBSA=9∶1,NARS∶NHSA=7∶1。经光谱修正技术计算结合产物的实际摩尔吸光系数分别为εBSA-ARS(537nm)=2.517×104L.mol-1.cm-1,εHSA-ARS(519nm)=2.051×104L.mol-1.cm-1,检出限BSA为19mg/L,HSA为23mg/L。经探讨该结合反应机理符合Langmuir吸附聚集反应方程。     

EDS X-Ray Investigation of Interdiffusion in Au–Ni Micro- and Nanolayers

The interdiffusion process in thin and thick (500nm–60µm) Au–Ni layers deposited on different substrates is studied using the EDS technique. In-depth X-ray analysis based on the Pouchou and Pichoir method is applied for obtaining the concentration profiles in nanometre scale multi-layers. A theoretical analysis using the Darken method is employed for modelling interdiffusion in the Au–Ni system. Computer simulations, where intrinsic diffusivities of the Au and Ni are functions of composition, are presented and compared with experimental results.     

乙烯在纳米催化剂InVO4-TiO2上的可见光降解

The InVO₄-TiO₂ nano-crystalline photocatalyst was prepared by sol-gel method and characterized by DRS, FTIR, Raman and XRD. The photocatalytic activities of the prepared sample were investigated by photocatalytic degradation of ethylene in the gaseous phase under visible light irradiation (λ>450 nm). The results indicate that both of pure TiO₂ and InVO₄ or their simple mixture show no photocatalytic activities for degradation of ethylene under visible light irradiation. However, as-synthesized InVO₄-TiO₂ catalyzes the degradation of ethylene into CO₂ under visible light irradiation. In addition, the interaction between InVO₄ and TiO₂ results in some structural distortion to all the crystal forms of TiO₂ in as-synthesized catalyst InVO₄-TiO₂.     

用重复卷积法求解物理宽化函数

用重复卷积法求解物理宽化函数吴万国,林嘉　（福州大学中心实验室,福州３５０００２）（中国（福建）对外贸易中心集团,福州３５０００１）关键词Ｘ射线衍射,晶粒度,晶格畸变,重复卷积粉末试样的Ｘ射线衍射谱线一般具有一定的宽度,引起话线宽化的主要原因有仪器致...     

Probability theory and polymer physics

This study applies the theory of stochastic processes to the equilibrium statistical physics of polymers in solution. The topics treated include random copolymers and randomly branching polymers, with self-consistent mean field effects. A new and more natural way of dealing with Boltzmann weighting is discussed, which makes it possible from the beginning of a calculation to consider only the physical polymer conformations. We also show that in general the random copolymer problem can be reduced to the ordinary polymer problem, and treat the self-consistent field problem for a general branching polymer.     

Characteristic polynomial theory of two-stage phase shifting algorithms

Two-stage phase shifting algorithms make possible to directly recover the sum or the difference of the optical phase of two different fringe patterns. These algorithms can be built by combining the known phase shifting algorithms in a non-linear way. In this work, we associate a two-dimensional characteristic polynomial to each two-stage phase shifting algorithm. This enables us to qualitatively compare their behaviour against the main systematic error sources, by means of an analysis protocol like that used for phase shifting algorithms. We show that this tool allows to understand the propagation of properties from precursor phase shifting algorithms to new evaluation algorithms built from them. As an experimental application, a wavefront distortion evaluation in differential phase-shifting interferometry is presented.     

Distorted wave response of ultrasonic annular stator incorporating non-uniform geometry

The traveling wave ultrasonic stator is normally fabricated with teeth. The tooth geometry improves the driving speed, but it creates natural frequency splitting and mode contamination, especially a distorted traveling wave. A dynamic model of a stepped-plate periodic stator is developed to examine the distortion. The stator is treated as an annular supported by a thin mid plate, and the support stiffness is formulated by using equivalent energy principle. The effects of the tooth and mid plate on the natural frequency and vibration mode are examined by using the perturbation method. The rules governing the frequency splitting, frequency perturbation as well as mode contamination are also identified. The traveling wave response and elliptical trace on stator surface are obtained by using the mode superposition method and they are proved to be distorted due to the tooth geometry. The response at the repeated doublets becomes coupled forward and backward traveling waves, but that at the split doublets becomes coupled forward traveling, standing and backward traveling waves. The results indicate that the tooth mass instead of the stiffness decreases the vibration amplitude and driving speed of the dominant wave, but their effects are different at the repeated and split doublets. Inspection of the model implies that the distortion can be suppressed by using a suitable combination of the wavenumber, tooth count, tooth height and occupying fraction. Numerical calculations are carried out to demonstrate the tooth geometry effect on the transient waveform, driving speed and elliptical trace. The optimization of the tooth geometry that can help achieve a purer traveling wave is discussed.