Fu Yi-Bei

A study on radiation resistance of siloxane foam containing phenyl

Abstract In this paper, the radiation effect on spherical open-porous polymethylphenylvinyl siloxane foam was studied in different atmospheres at room temperature. The behavior of unirradiated and irradiated materials was studied by SEM, FTIR, TG, GC/MS, etc. The results indicate that the gas yield increases linearly with increasing dose. Furthermore, there were some changes in the microscopic structure, composition, and mechanical property, but the maximum thermal decomposition temperature of the sample alters little with the dose.

SOLVENT EXTRACTION SEPARATION OF RUBIDIUM WITH A CROWN ETHER FOR NEUTRON ACTIVATION ANALYSIS IN ROCK SAMPLES

The extraction behavior of rubidium with a crown ether has been studied and methods for the separation and determination of rubidium have been developed. Rubidium was separated with tetraphenylborate from sample solution, and then quantitatively extracted into nitrobenzene by 18-crown-6 from 0.05 mol/l picric acid (pH 6) and back-extracted by 6 mol/l hydrochloric acid. Rubidium was determined by the neutron activation method in rock samples.

Study of analytic potential energy function and stability for PuOn + with density functional theory

The theoretical study of PuOn + (n=1,2,3) using a density functional method shows that PuO+ (X6Si-) and PuO2+ (X5Si-, 7Si-, 9Si-) ions are stable and the PuO3+ (4Si+, 6Si+) ion is unstable. The analytic potential energy functions of X6Si- for PuO+ and X5Si-, 7Si-, 9Si- for PuO2+ have been derived and their force constants and spectroscopic data have been calculated.

Geometrical structures, vibrational frequencies, force constants and dissociation energies of isotopic water molecules （H2O, HDO, D2O, HTO, DTO, and T2O） under dipole electric field

The dissociation limits of isotopic water molecules are derived for the ground state. The equilibrium geometries, the vibrational frequencies, the force constants and the dissociation energies for the ground states of all isotopic water molecules under the dipole electric fields from ?0.05 a.u. to 0.05 a.u. are calculated using B3P86/6-311++G(3df,3pf). The results show that when the dipole electric fields change from ?0.05 a.u. to 0.05 a.u., the bond length of H?O increases whereas the bond angle of H?O?H decreases because of the charge transfer induced by the applied dipole electric field. The vibrational frequencies and the force constants of isotopic water molecules change under the influence of the strong external torque. The dissociation energies increase when the dipole electric fields change from ?0.05 a.u. to 0.05 a.u. and the increased dissociation energies are in the order of H2O, HDO, HTO, D2O, DTO, and T2O under the same external electric fields.

Potentional Energy Function and Stability of PuO n

用密度泛函Ｂ３ＬＹＰ方法对ＰｕＯ＾ｎ＋（ｎ＝１，２，３）分子离子进行了理论研究。结果表明，ＰｕＯ＾＋、ＰｕＯ＾２＋分子离子能稳定存在，电子状态是Ｘ＾６∑＾－（ＰｕＯ＾＋）、Ｘ＾５（ＰｕＯ＾２＋）、＾９∑＾－（ＰｕＯ＾２＋、＾７∑＾－（ＰｕＯ＾２＋），导出了相应的几何性质，力学性质和光谱数据。ＰｕＯ＾３＋分子离子不能稳定存在。

Studies on the Structures and Optical Properties of TiO2 Doped with Transition Metals

The structures and optical properties TiO2 doped with 4th periodic transition metal ions were investigated in this paper. The characterization results of X-ray photoelectron spectroscopy and X-ray diffraction show that the metal ions exist in oxidative states, and composites form because of the reaction between doped metal ions and TiO2. The absorption spectroscopy of TiO2 doped with zinc is mainly in ultraviolet region, close to that of pure TiO2. While for TiO2 doped with other transition metal ions including V, Cr, Mn, Fe, Co, Ni and Cu ions, the absorption spectroscopies cover ultraviolet region and visible light region, which are broaden greatly comparing with that of pure TiO2.

The reduction kinetics of pertechnetate by thiocyanate in perchloric acid medium

The reduction kinetics of pertechnetate by thiocyanate in perchloric acid is studied by spectrophotometric method. The effect of the concentrations of pertechnetate, hydrogen ion and thiocyanate on the reaction rate is investigated. The kinetic expression at 25°C is: −dCVII/dt=(2.2±0.4)·10−3 [TcO4−]1.1 [H+]3.2 [SCN−]3.3 The effect of temperature on the reaction rate is studied. The activation energy is 91 kJ/mol. The possible mechanism of the reaction is discussed.

Neutron activation analysis of gold and iridium in steel

A method of determination of trace gold and iridium in steel is presented. The samples were preconcentrated with an anion exchanger. The chemical recoveries were determined by an isotope tracer technique using198Au and192Ir.

Ionic Charge State Distribution of Au Plasma for 7-Ion System

The present work extends the previous work [2] on 5-ion system to consider 7-ion system (i.e., Au47+~Au53+). It is found that more highly charged ions, e.g., Au53+, Au54+ etc., could be able to be neglected, however, less highly charged ions, e.g., Au47+, Au46+ etc., are rather important. Therefore, a new idea to consider 8-ion system, i.e., Au46+~Au53+, is under way. As a supplement, we discuss the simultaneous reaction, which would be important in this sort of works.

Spin polarization effect for Os2 molecule

Density functional Theory (DFT) (B3p86) of Gaussian03 has been used to optimize the structure of Os2 molecule. The result shows that the ground state for Os2 molecule is 9-multiple state and its electronic configuration is 9Σg+, which shows spin polarization effect of Os2 molecule of transition metal elements for the first time. Meanwhile, we have not found any spin pollution because the wavefunction of the ground state does not mingle with wavefunctions with higher energy states. So, the fact that the ground state for Os2 molecule is a 9-multiple state is indicative of spin polarization effect of Os2 molecule of transition metal elements. That is, there exist 8 parallel spin electrons. The non-conjugated electron is greatest in number. These electrons occupy different spacious tracks, so that the energy of Os2 molecule is minimized. It can be concluded that the effect of parallel spin of Os2 molecule is larger than the effect of the conjugated molecule, which is obviously related to the effect of electron d delocalization. In addition, the Murrell–Sorbie potential functions with the parameters for the ground state 9Σg+ and other states of Os2 molecule are derived. Dissociation energy De for the ground state of Os2 molecule is 3.3971eV, equilibrium bond length Re is 0.2403nm, vibration frequency ωe is 235.32cm−1. Its force constants f2, f3 and f4 are 3.1032×102aJ.nm−2, −14.3425×103aJ.nm−3 and 50.5792×104aJ.nm−4 respectively. The other spectroscopic data for the ground state of Os2 molecule ωeχe, Be and αe are 0.4277cm−1, 0.0307cm−1 and 0.6491× 10−4cm−1 respectively.