[en] This work presents a systematic density functional theory study of the structural, electronic, and magnetic properties of the golden cage doped with a transition-metal atom, M@Au₁₆^q (M=Cr, Mn; q=0, −1). We found that the endohedral structures are always favored. The Cr@Au₁₆⁻ clusters show smaller X-A energy gaps, suggesting that its geometric and electronic structures alter remarkably due to the addition of Cr atom. However, the characteristics of the Mn@Au₁₆⁻ species include their remarkably high X-A energy gaps, indicating doping by Mn atom could stabilize the hollow Au₁₆⁻ cage. Furthermore, the magnetic moment of the impurity Mn/Cr atom is slightly quenched. - Highlights: • The endohedral structures are always favored for Cr@Au₁₆^q and Mn@Au₁₆^q clusters. • All the doped cluster anions show larger ADE and VDE. • Atom like magnetism is maintained by doping into the golden hollow cage. • A new endohedral golden cage with varying magnetic properties may exist

[en] Ionizing radiation (IR) therapy is a primary treatment for glioblastoma multiforme (GBM), a common and devastating brain tumor in humans. IR has been shown to induce PI3K-Akt activation in many cell types, and activation of the PI3K-Akt signaling pathway has been correlated with radioresistance. Initially, the effects of IR on Akt activation were assessed in multiple human GBM cell lines. Next, to evaluate a potential causative role of IR-induced Akt activation on radiosensitivity, Akt activation was inhibited during IR with several complementary genetic and pharmacological approaches, and radiosensitivity measured using clonogenic survival assays. Three of the eight cell lines tested demonstrated IR-induced Akt activation. Further studies revealed that IR-induced Akt activation was dependent upon the presence of a serum factor, and could be inhibited by the EGFR inhibitor AG1478. Inhibition of PI3K activation with LY294002, or with inducible wild-type PTEN, inhibition of EGFR, as well as direct inhibition of Akt with two Akt inhibitors during irradiation increased the radiosensitivity of U87MG cells. These results suggest that Akt may be a central player in a feedback loop whereby activation of Akt induced by IR increases radioresistance of GBM cells. Targeting the Akt signaling pathway may have important therapeutic implications when used in combination with IR in the treatment of a subset of brain tumor patients

[en] A discharge-pumped 351 nm XeF (B-X) excimer laser has been developed. For improving output efficiency and energy and achieving stationary discharge, the laser adopted a new switching power supply, compact Chang's electrodes and spark preionization structure, and the optimization of storage/discharge capacitances and working gas mixture was performed. The maximum laser efficiency of the laser is 0.88%. When the laser works at 30 kV with the maximum repetition rate of 80 Hz, the output energy is about 153 mJ/pulse, the average power is 12.9 W, the pulse-to-pulse energy stability is no more than 4%, and the beam dimensions are 7 mm x 22 mm near the output window. The laser has been applied to the experiments of the printed circuit board (PCB) lithography system based on resist exposure. (authors)

[en] The orientation of CO molecule controlled by two-color femtosecond laser pulse and positively chirped laser pulse is investigated theoretically. Compared with the single two-color or positively chirped laser pulse, the combination of two laser pulses with an optimized delay time can greatly improve the degrees of the positive and negative molecular orientation, respectively. The effects of intensity of two-color femtosecond laser pulse on molecular orientation are discussed, and the molecular orientation can be achieved by a calculated intensity. Additionally, the delay time between two-color femtosecond laser pulse and positively chirped laser pulse can significantly enhance the molecular orientation. Furthermore, by varying the carrier frequency and the chirp value of the positively chirped laser pulse, it is shown that the molecular orientation can be changed to some degree. The positive and negative molecular orientation can also be manipulated by adjusting the relative amplitude of the second harmonic field with respect to the fundamental. Graphical abstract: .

[en] A simple filter, which is composed of transmission lines and can reject interference is introduced. Its working principle, characteristics and some applications in the National Synchrotron Radiation Laboratory (NSRL) are described

[en] The collective properties along the yrast line in well-deformed even–even ${}^{164-<!--\; ???\; -->178}$ Yb isotopes are investigated by pairing self-consistent total Routhian surface (TRS) calculations and extended E-gamma over spin (E-GOS) curves. The calculated results from ground-state deformations, e.g., ${\mathrm{\beta <!--\; ??\; -->}}_2$, are in agreement with previous theoretical predictions and available experimental data. The basic behaviors of moment of inertia are reproduced by the present TRS calculations and discussed based on the aligned angular momenta. The centipede-like E-GOS curves indicate that the non-rotational components appear along the yrast sequences in these nuclei, which can explain the discrepancy in the moment of inertia between theory and experiment to some extent. The further extended E-GOS curves, which include the first-order rotation–vibration coupling, appear to provide possible evidence of vibrational effects in the well-deformed nuclei of ${}^{164-<!--\; ???\; -->178}$Yb.

[en] The geometrical structures, relative stabilities, electronic and magnetic properties of small B_nAl⁻ (2 ≤ n ≤ 9) clusters are systematically investigated by using the first-principles density functional theory. The results show that the Al atom prefers to reside either on the outer-side or above the surface, but not in the centre of the clusters in all of the most stable B_nAl⁻ (2 ≤ n ≤ 9) isomers and the one excess electron is strong enough to modify the geometries of some specific sizes of the neutral clusters. All the results of the analysis for the fragmentation energies, the second-order difference of energies, and the highest occupied-lowest unoccupied molecular orbital energy gaps show that B₄Al⁻ and B₈Al⁻ clusters each have a higher relative stability. Especially, the B₈Al⁻ cluster has the most enhanced chemical stability. Furthermore, both the local magnetic moments and the total magnetic moments display a pronounced odd-even oscillation with the number of boron atoms, and the magnetic effects arise mainly from the boron atoms except for the B₇Al⁻ and B₉Al⁻ clusters. (atomic and molecular physics)

[en] Highlights: • The bond length of MCl and MO in extraction complexes was K⁺ > Na⁺ > Li⁺. • The form of FeCl₄⁻ was easier in CaCl₂ brine solution than MgCl₂ under the same concentration. The extraction rules of mental ions in salt lake brine by TBP-FeCl₃ extraction system were investigated. The theoretical calculations and experiments were conducted in order to explicit the behavior of cations Li⁺, Na⁺, K⁺, Mg²⁺ and Ca²⁺ in extraction process. The results of theoretical calculations indicated the bond length of MCl and MO in extraction complexes was K⁺ > Na⁺ > Li⁺. The results of experiments suggested LiCl had much stronger effect on PO in TBP than NaCl and KCl and the form of FeCl₄⁻ was easier in CaCl₂ solution than MgCl₂ under the same concentration.

[en] We report on the calculations of transition wavelengths and weighted oscillator strengths for 2s²2p⁶−2s2p⁶np (4 ≤ n ≤ 20) electric dipole (E1) transitions of Cu¹⁹⁺ ion. The flexible atomic code (FAC) has been adopted for the calculations. Comparisons are made with the experimental data available, showing that the present results for 4 ≤ n ≤ 6 are more accurate than the previous calculated values. Furthermore, combining the quantum defect theory (QDT) with the transition energies of 2s²2p⁶−2s2p⁶np, the quantum defects for 2s2p⁶np Rydberg series of Cu¹⁹⁺ ion are determined. In addition, the energies of any highly excited states (n > 20) for this series can be reliably predicted using the QDT and the given quantum defects. The ionization energies for Cu¹⁹⁺ and Cu²⁰⁺ ions are also calculated and they excellently accord with previous experimental and calculated values. (atomic and molecular physics)

[en] Density functional calculations are performed to investigate the electronic and structural properties of M@Si₆ (M = Pr, Gd, Ho). Generalized Koopmans' theorem is applied to predict the vertical detachment energies and simulate the photoelectron spectra (PES). Subsequently, a detailed comparison between previously published experimental PES spectra and the present theoretical simulations helps to identify the ground state structures. The most stable M@Si₆^- (M = Pr, Gd, Ho) is a three-dimensional structure with the lanthanide-metal atom sitting on top (or bottom) of the regular pentagonal bipyramid. Instead, the neutral species show the impurity as a four-coordinate atom in the equatorial plane of pentagonal bipyramid. Moreover, the nucleus independent chemical shift (NICS) is discussed at various points at and over or under the center of the Si₅ ring plane, and the negative NICS values support the aromatic character of the M@Si₆^- (M = Pr, Gd, Ho) clusters. -- Highlights: → We examine the electronic and structural properties of M@Si₆ (M = Pr, Gd, Ho). → The impurity M in M@Si₆^- sits on top of the regular pentagonal bipyramid. → The impurity M in M@Si₆ becomes a part of the pentagonal ring. → The photoelectron spectra are simulated to compare with the experimental results. → NICS values at various points are calculated to discuss aromaticity.