[en] Glass forming ability/range of the Mo-Pd binary metal system was studied by thermodynamic calculations employing Miedema's model and ion beam mixing of multiple metal layers. The thermodynamic calculations predict a narrow composition range of 8-26 at% Pd, within which metallic glass formation is energetically favored, whereas the experimental results showed that ion beam mixing was able to synthesize metallic glasses within a composition range 13-30 at% Pd, which was well in accordance with the prediction. Besides, in the Mo₇₀Pd₃₀ multilayered films, with varying the irradiation dose, a dual-phase metallic glass was formed, and it could be considered as an intermediate state. The possible mechanism for the formation of the metallic glasses was also discussed in terms of the atomic collision theory.

[en] In this letter, we present the first experimental results of climbing a vibrational ladder by Raman chirped adiabatic rapid passage. We obtain the bandwidth necessary for this experiment by utilizing pulses from a unique dual-wavelength high-intensity laser. The vibrationally excited molecules are field ionized by an intense 180 fs laser pulse, enabling us to probe the extent of the vibrational excitation of the symmetric stretch based on an enhanced ionization calculation. (letter to the editor)

[en] Full text: This study evaluated the safety and efficacy of strontium- 89-chloride in bone metastases patients without bone pain. Methods; an evaluation was made on 54 patients with no painful bone metastases, treated with a single IV dose of 1.48-2.22MBq/kg of strontium-89-chloride. The retreatment was between 3 and 6 months after therapy. Results: The total response rate was 74.0% in 54 patients with no painful bone metastases. The response rate in the focal size>2cm patients was significantly lower than the focal size of 2cm (33.3%? 66.6%, X2=14.9, P<00.1). The side effects of strontium-89-chloride were thrombocytopenia and neutropenia, which were generally mild and reversible. Conclusion: Strontium-89-chloride is effective and safe in painless bone metastases patients. (author)

[en] In this communication, the delayed bistable system under the excitation of two different periodic signals is investigated by numerical simulation. It is found that the delay can induce quasi-periodic vibrational resonance. With the cooperation of the strong high-frequency signal and the delay, the weak low-frequency signal in the delayed bistable system can be enhanced greatly. (fast track communication)

[en] We propose an extended Finnis-Sinclair (FS) potential by extending the repulsive term into a sextic polynomial for enhancing the repulsive interaction and adding a quartic term to describe the electronic density function. It turns out that for bcc metals the proposed potential not only overcomes the 'soft' behaviour of the original FS potential, but also performs better than the modified FS one by Ackland et al, and that for fcc metals the proposed potential is able to reproduce the lattice constants, cohesive energies, elastic constant, vacancy formation energies, equations of state, pressure-volume relationships, melting points and melting heats. Moreover, for some fcc-bcc systems, e.g. the Ag-refractory metal systems, the lattice constants, cohesive energies and elastic constants of some alloys are reproduced by the proposed potential and are quite compatible with those directly determined by ab initio calculations

[en] We present a laser architecture to obtain continuous-wave orange–yellow radiation at 589 nm. A 808 nm diode-pumped the Nd:GdVO₄ crystal emitting at 1341 nm. A part of the pump power was then absorbed by the Nd:GdVO₄ crystal. The remainder was used to pump the Nd:YLiF₄ (Nd:YLF) crystal emitting at 1053 nm. Intracavity sum-frequency-mixing at 1341 and 1053 nm was then realized in a LiB₃O₅ (LBO) crystal to produce orange–yellow radiation. We obtained a continuous-wave output power of 352 mW at 589 nm with a pump laser diode emitting 18.4 W at 808 nm. (letter)

No abstract available

[en] The structural transformation and disordered atomic packing of metallic glasses in a selected immiscible system at equilibrium, i.e. the Cu-Nb system characterized by a positive heat of formation, are studied using ion beam mixing far from equilibrium. The experimental results indicate that the Cu-Nb metallic glasses could be formed in a composition range from 30 to 85 at.% of Nb and that the Cu-Nb metallic glasses are formed through two different structural phase transition routes, i.e. from the Nb-based body centred cubic and face centred cubic solid solutions, in which the two distinct predominant atomic packings have icosahedral and icositetrahedral orderings, respectively, revealed by the respective diffraction patterns. These observations not only help in formulating a general atomic structural spectrum for the binary metallic glasses, but also suggest an important concept of structural heredity: that the crystalline structure of the constituent metals plays a decisive role in determining the atomic structure of the resultant metallic glasses. (letter to the editor)

[en] An n-body potential is developed and satisfactorily applied to hcp metals, Co, Hf, Mg, Re, Ti, and Zr, in the form of long-range empirical potential. The potential can well reproduce the lattice constants, c/a ratios, cohesive energies, and the bulk modulus for their stable structures (hcp) and metastable structures (bcc or fcc). Meanwhile, the potential can correctly predict the order of structural stability and distinguish the energy differences between their stable hcp structure and other structures. The energies and forces derived by the potential can smoothly go to zero at cutoff radius, thus completely avoiding the unphysical behaviors in the simulations. The developed potential is applied to study the vacancy, surface fault, stacking fault and self-interstitial atom in the hcp metals. The calculated formation energies of vacancy and divacancy and activation energies of self-diffusion by vacancies are in good agreement with the values in experiments and in other works. The calculated surface energies and stacking fault energies are also consistent with the experimental data and those obtained in other theoretical works. The calculated formation energies generally agree with the results in other works, although the stable configurations of self-interstitial atoms predicted in this work somewhat contrast with those predicted by other methods. The proposed potential is shown to be relevant for describing the interaction of bcc, fcc and hcp metal systems, bringing great convenience for researchers in constructing potentials for metal systems constituted by any combination of bcc, fcc and hcp metals.

[en] Based on the recently constructed Ni-Zr-Al n-body potential, Monte Carlo simulations are performed to study the glass formation and associated structural evolutions in the system. The micro-chemical inhomogeneity (MCI) parameter and Honeycutt and Anderson (HA) pair analysis are employed to investigate both the chemical short-range orders and topological short-range orders for the ternary Ni-Zr-Al metallic glasses. Results reveal that remarkable chemical short-range orders (CSROs) exist in the ternary Ni-Zr-Al metallic glasses and are strongly influenced by the chemical interactions among the constituent elements. Moreover, topological short-range orders are clearly formed in the ternary Ni-Zr-Al metallic glasses, with the most remarkable characteristic being the icosahedral local packing. Similarly to CSRO, the extent of icosahedral short-range orders formed in the Ni-Zr-Al system varies distinctly with the chemical composition. In addition, simulation results reveal that chemical short-range orders and topological short-range orders turn out to be influenced by different factors. Unlike CSRO, both chemical interactions and geometrical constraints play important roles in forming the topological short-range orders.