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The energetic atom deposition of thin Au/Au(100) film has been studied by molecular dynamics simulation using the Au-Au interatomic interaction potential with embedded atom method. By investigating the variation of coverage curves and Bragg diffraction intensities during the film growth, the transition of Stranski-Kranstanov growth mode to Frank-van der Merwe growth mode was observed with the increase of the incident energy of deposition atoms. The role of energetic atoms in the film growth is discussed by analyzing the transport properties of deposited atoms and the evolution of incident energy and substrate temperatures.

Atomic spectra of singly ionized praseodymium have been measured by collinear fast-ion-beam laser spectroscopy. Hyperfine structure in the 576 nm line was resolved and the magnetic dipole and electric quadruple coupling constants were determined.

The single electron impact ionization cross sections of Ar+, Kr+, In+ and Ge+ were measured on the improved electron-ion impact apparatus at Fudan University. The Ar+, Kr+ and In+ experimental results are in good agreement with data from other laboratories. The cross section of Ge+ was measured for the first time. The experimental results indicate that the indirect ionization process gives a larger contribution to the total ionization cross section of In+, as compared to the other three targets. The experimental data were compared with our Distorted-Wave-Born-Exchange-Approximation (DWBEA) calculation, the Lotz formula, and Configuration-Averaged-Distorted-Wave (CADW) calculations.

The optical isotope shifts in the transition - of Nd II were measured by using collinear fast-ion-beam laser spectroscopy. The changes in mean-square nuclear charge radii among five even - even neodymium isotopes were deduced from the measured optical isotope shifts: (142,144) 0.269; (144,146) 0.259; (146,148) 0.278; (148,150) 0.403. The configuration admixtures of the previously unclassified level were quantitatively analysed to be , , and with mixing probabilities of 13%, 85%, 2%, respectively.

The charge states of sputtered cesium and oxygen ions/atoms from metal surfaces have been discussed with the time-dependent Newns-Anderson model. The final charge state distribution has been calculated as a function of work function of the surfaces. The calculated results fit the experimental data well. Besides, the dependence of the final charge states of the sputtered oxygen particles on the surface temperature is also predicted.

We previously determined the effects of dietary selenium (Se) deficiency or excess on mRNA abundance of 12 selenoprotein genes in pig tissues. In this study, we determined the effect of dietary Se on mRNA levels of the remaining porcine selenoprotein genes along with protein production of 4 selenoproteins (Gpx1, Sepp1, Selh, and Sels) and body glucose homeostasis. Weanling male pigs (n = 24) were fed a Se-deficient (

We report the 170° backscattering cross sections of 4He from O in the energy range of 2.0–9.0 MeV. Our measurements show that the alpha-oxygen scattering remains Rutherfordlike up to Eα = 2.35 MeV, and there exist two energy regions, 5.55–5.85 MeV and 8.50–8.80 MeV, where the cross sections present an enhanced and smooth variation. The measured cross sections in these two regions exhibit enhancement factors of 9.7 and 34, respectively, compared to the Rutherford values. In the 8.50–8.80 MeV region, the cross sections at scattering angles of 160°, 165°, 170° and 175° were measured and found to be strongly angle-dependent. The strongest resonance was seen at 7.60 MeV, where the cross section is 200 times its Rutherford value. We report the use of this resonance to measure the O areal density on a Cu surface, with a sensitivity of 1 × 1015 oxygen atoms cm 2 . We have also studied the scattering angle dependence of the threshold energy at which the cross section begins to depart from its Rutherford value. Our experimental results are not in agreement with the prediction from the analytical formula developed by Bozoian et al. [Nucl. Instr. and Meth. B 51 (1990) 311].

An energy dependence of the axial minimum channeling yield in GexSi1-x/Si(100) Strained-layer superlattice is observed in the energy range of impinging He+ ions from 1.2 to 3.0 MeV. For [100] axial channeling, the measurements are in agreement with what have been known in a single crystal. However, for [110] axial channeling, it is found that the minimum channeling yields increase markedly with the increase of He+ ion energy, which is contrary to the general channeling behaviors in a single crystal. A tentative model is suggested to explain this aberrance.

Non-Rutherford cross sections are needed in high energy backscattering spectroscopy. Bozoian et al. have developed a classical model and derived an analytical expression to calculate the projectile energy E nr at which the scattering cross section begins to deviate from its Rutherford value. We make comments on the model and conclude, through discussions and experiments, that (1) it is useful in estimating the energy value but gives incorrect dependences of E nr on the departure factor F and the scattering angle χ, and (2) these inadequacies originate from the classical approach, which is an over-simplified and phenomenal description of nature.

The hyperfine structure of the transition 5d6s b1D2 – 5d6p 3D1o (576.91 nm), 5d6s b1D2 – 5d6p x3F3o (597.11 nm) and 5d6s b1D2–5d6p x3F2o (612.61 nm) of 139La II has been measured by collinear laser-ion-beam spectroscopy. The magnetic-dipole constants A and electric-quadrupole constants B of the involved levels were determined.

Time-resolved collinear fast-beam laser spectroscopy has been used to measure the lifetime of the T=23 537 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, J=9/2 odd-parity [abbreviated as (23 537)${\mathrm{\ifmmode^\circ\else\textdegree\fi{}}}_{9/2}$] level in Nd ii. Nanosecond pulsed excitation was achieved with the Doppler switching technique. The fast ions were selectively excited from the metastable 4${\mathit{f}}^{4}$5d $^{6}$${\mathit{K}}_{9/2}$ level to the (23 537)${\mathrm{\ifmmode^\circ\else\textdegree\fi{}}}_{9/2}$ level by the light of a cw dye laser. The decay of the resonance fluorescence photons emitted in the transition to the ground 4${\mathit{f}}^{4}$6s $^{6}$${\mathit{I}}_{7/2}$ level, as a function of the flight distance, was observed. The decay length was scaled into the decay time by the ion velocity, which was determined using the optical resonance itself. The lifetime is 27.7(9) ns.

The optical isotope shifts in the transition 4f4 5d 6 K9/2 -(23 537)9/2 0 (5702 A) of Nd II by collinear fast-ion-beam laser spectroscopy have been used to deduce for the first time that the mixing probabilities of the configurations 4f3 5d2 , 4f4 6p and 4f3 5d6s of the level (23 537)9/2 0 are 0.84, 0.15 and 0.01 respectively.

Paper discoloration and its tensile strength degradation caused by 2.1 MeV external proton beam bombardment under low beam current density ( 2 ) were measured as a function of the number of incident protons. The target temperature reached during bombardment was measured using an infrared thermometer. Under low beam current density, paper heating is negligible and the paper deterioration depends only on the total beam fluence. Some of the experimental results are presented and discussed for several types of paper, including one used for traditional Chinese paintings.

The optical isotope shifts of five even isotopes of neodymium have been measured by using collinear ion beam laser spectroscopy (CIBLS). Isotopically pure NdII ions with energy of 30ke V from an isotope separator were collinearly interacted with light from a tunable dye laser and selectively excited from a metastable level of 4f4 5d6 K9/2 to the (23537)9/20 level by Doppler tuning technique. The resonant excitation frequency values for each Nd isotope with mass number of 142, 144, 146, 148 and 150 were obtained. After the separation of the normal and specific mass shift and the field shift from the experimentally measured isotope shift, the configuration of the (23537)9/20 level was decomposed into 4f4 6p, 4f3 5d2 and 4f3 5d6p, and their fractions, for the first time. were determined to be 0.12-0.13, 0.88-0.85 and 0-0.02, respectively.

The R-matrix theory is used to analyze the elastic scattering cross sections of 4 He from 16 O in the energy range 2.0–9.0 MeV. Level parameters of the compound nucleus 20 Ne, i.e., the spins, parities, resonant energies, and widths of the excited levels for alpha energies from 2.5 to 9.7 MeV, were identified. These level parameters can then be used, for application purposes, to check either the measured values of resonant cross sections or the cross sections at certain particular angles according to the experimental conditions.