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Photochemical vapor generation (PVG) of germanium (Ge) was first reported in this work. The synergistic effect from cobalt/chloride ions and air-liquid interfaces was found for the PVG of Ge. No obvious signal response was observed from the standard solution of Ge in 10% (v/v) formic acids (FAs) under UV irradiation. The addition of 300 mg L−1 of Co2+ and 30 mmol L−1 of Cl− resulted in enhanced photochemical reduction for Ge, and the introduction of air-liquid interfaces proceeding and succeeding the sample solution caused another 4.6 folds of enhancement in signal response of Ge. Under the selected condition, the limit of detection (LOD, 3σ, n = 11) was obtained to be 0.008 ng mL−1 with inductively coupled plasma mass spectrometry (ICP MS) measurement. A good precision, expressed as a relative standard deviation (RSD, n = 7) of 2.0%, was found from replicated measurements of 2 ng mL−1 of Ge. The generation efficiency was found to be no better than 9 ± 2%. The PVG mechanism of Ge was investigated in this work. The new finding is useful for understanding the principle of PVG, and further exploring the analytical and environmental application of PVG. [ABSTRACT FROM AUTHOR]

The recently released CENDL-3.2 nuclear data library is deemed as an important achievement in the field of nuclear data research in China. To verify the applicability of the library to the shielding calculation of PWR and analyze the influence of multigroup cross-section parameters on the shielding calculation, ARES-MACXS module is used to process the MATXS format multigroup library based on CENDL-3.2 to generate multigroup working cross sections for PWR shielding calculation. VENUS-3 experimental facility has a clear and complete geometry. It is often used to test the ability of the advanced transport calculation method of calculating RPV fast neutron flux and to evaluate the accuracy of cross-section library. Different cross-section parameters are chosen for ARES to calculate VENUS-3 benchmark, and equivalent neutron flux of 58Ni(n,p)58Co, 115In(n,n′)115mIn and 27Al(n,α)24Na detectors is calculated according to the data provided by the benchmark report. The numerical results demonstrate that almost all the relative deviations between the calculated results and the experimental results are within 20%, which satisfies the requirement of shielding calculation. CENDL-3.2 is suitable for PWR shielding calculation. The comparison of various cross-section parameters results indicates that multigroup cross-section parameters have large effects on the transport calculation results. [ABSTRACT FROM AUTHOR]

[Display omitted] • PVG of Zinc and Gallium was reported for the first time. • The addition of Cu2+ can largely promote the photochemical reduction of Zn and Ga. • The generated volatile species were speculated to be carbonyl compounds. Photochemical vapor generation (PVG) of Zinc (Zn) and Gallium (Ga) was firstly reported in this study. The main parameters influencing PVG of Zn and Ga were investigated with inductively coupled plasma mass spectrometry (ICP-MS), such as the type and concentration of low molecular weight organic acids (LMWOAs), the concentration of transition metal ions and their synergistic effects, the wavelength and time of UV irradiation, and pH of sample solution. Formic acid (FA) and Cu2+ were required for the generation of volatile species of Zn and Ga. In addition, the effects of interfering ions on the PVG of Zn and Ga were investigated. Good precisions with 2.3% and 2.7% were obtained under the selected conditions for replicate measurement of 200 ng mL−1 Zn and Ga standard solution (n = 7), respectively. The limits of detection (LOD, 3σ, n = 11) were calculated to be 8.8 ng mL−1 and 0.77 ng mL−1 for Zn and Ga with PVG-ICP-MS measurement, respectively. Carbonyl compounds were speculated to be formed in this study. Moreover, nanoparticles containing Cu, Zn or Ga were found in liquid solution after UV irradiation, which may be useful for investigating the formation of natural nanoparticles in environment as well as the isotope fractionation of Zn and Ga in photochemical processes. [ABSTRACT FROM AUTHOR]

• A multi-group cross section generation code ARES-MACXS was developed independently. • The latest version of Chinese Evaluated Nuclear Data Library CENDL-3.2 is used as base library. • The effects of multi-group cross-section parameters on fusion shielding calculation are analyzed. • Suggestions for selection of cross-section parameters for fusion deterministic shielding calculation and problems in the generation of multi-group cross-sections are proposed, which provides a valuable interest for fusion engineering shielding calculation. Fusion devices are always characterized by complex geometries and high neutron energy, which pose great challenges in the transport calculations. The discrete ordinates method (S N) with the advantages of high precision, high efficiency and the adaptivity to deep penetration problems is applied to fusion neutron calculations. High accuracy multi-group cross-sections are essential foundation to solve transport equations in S N methods. Therefore, how to select appropriate corrections and parameters in processing multi-group cross-sections for different nuclear systems is an interesting theme. We independently developed a multi-group cross-section generation code ARES-MACXS based on the Bondarenko method, which deals with the MATXS format multi-group cross-section library to generate problem-dependent macro cross-section data. In this paper, multi-group cross-sections are obtained for the fusion neutron shielding calculation based on the recently released CENDL-3.2 nuclear data library by ARES-MACXS. Moreover, a series of cross-section parameters and corrections are applied to calculate and analyze the OKTAVIAN-Fe benchmark. Comparisons with the RMC results shows that the parameters and corrections have varying extent of impacts for the multi-group cross-sections and a suitable combination is found for OKTAVIAN-Fe benchmark, which provides a valuable reference for other similar fusion engineering shielding calculation. [ABSTRACT FROM AUTHOR]

To solve the Boltzmann transport equation, the discrete ordinates method was applied using multi-group cross-sections, the accuracy of which affects markedly the transport calculation. For large shielding models, using fine-group cross-sections directly in the transport calculation is inefficient. Subsequently, the multi-group cross-section generation code ARES-MACXS utilized contribution theory in selecting a broad-group structure to meet calculational requirements of engineering shielding. For different computational problems, the ARES-MACXS code generates different optimal broad-group structures and corresponding multi-group working cross-sections. The numerical results indicate that, compared with the BUGLE-B7 broad-group structure, using these optimal broad-group structures may yield transport calculation results of higher accuracy with fewer groups. On the basis of a comprehensive analysis of different shielding calculation problems, ARES-60 broad-group structure with 46 groups of neutrons, 14 groups of photons is proposed, which is suitable for AP1000 shielding calculations and other similar PWR shielding calculations. • Multi-group cross-section generation code for radiation shielding calculation. • Optimization algorithms based on contribution theory for broad-group energy structures(ESs). • Broad-group ESs for fast/thermal flux, detector response and dose rate. [ABSTRACT FROM AUTHOR]

Shear failure of bedding slopes along weak zones is the main failure mechanism of the Layue landslide. To investigate the seismic dynamic response and destabilization failure mode of rock slopes with laminated fracture structures, a two-dimensional shaking table test with different ground motion inputs was performed, taking into consideration a variety of factors, such as the input seismic wave type and amplitude. The results show that the ground shaking characteristics and geological structure of the slope are the decisive factors in determining the seismic dynamic stability and failure mode of the slope. The horizontal dynamic response of the slope has an obvious elevation amplification effect and topographic effect, and the elevation has less influence on the vertical dynamic response of the slope. The ground motion amplification effect is related to the mechanical strength of the structural surface, the waveform of seismic waves, and the spectral characteristics. The sine wave has a more significant influence on the amplification effect of the slope than the natural wave. The slope cracks are initiated and propagate at the weakest part depending on the dominant structural surface and trace to the joint surface to form creep sections and locking sections. The strength parameter of the joint surface weakens under the action of geological agents, which results in two failure modes of the slope: the forward failure mode and the backward failure mode. The former refers to the potential slip belt lap through from the trailing edge to the front edge, where the sliding mass is cut out from the high position. The latter refers to the potential slip belt lap through the front edge to the trailing edge, and the sliding mass breaks down and is destroyed. Through a unique adaptive device, the seismic anchor cable can coordinate the deformation of the anchor cable with the rock-soil body, which can reduce the risk of a slope earthquake disaster. [ABSTRACT FROM AUTHOR]

Oral submucous fibrosis (OSF) caused by areca nut chewing is a prevalent fibrotic disease in Asia‐Pacific countries. Arecoline‐induced migration of fibroblasts (FBs) plays a vital role in the development of OSF. However, the specific molecular mechanisms involved remain unclear. Many studies have shown that tyrosine sulphation of chemokines can influence cell migration. Herein, we demonstrated that arecoline stimulates tyrosine sulphation of the chemokine receptor 4 (CXCR4) through the tyrosylprotein sulphotransferase‐1 (TPST‐1) to enhance the migration ability of FBs. Moreover, by RNA‐Seq analysis, we found that the most significantly altered pathway was the EGFR pathway after the arecoline stimulation for FBs. After the knockdown of arecoline‐induced EGFR expression, the tyrosine sulphation of CXCR4 was significantly decreased by the inhibition of TPST‐1 induction. Finally, in human OSF specimens, TPST‐1 expression was directly correlated with the expression of CXCR4. These data indicate that the arecoline‐induced tyrosine sulphation of CXCR4, which is regulated by TPST‐1, might be a potential mechanism that contributes to FB migration in OSF. [ABSTRACT FROM AUTHOR]

Multigroup constants are the foundation of neutron and photon transport problems, and the accuracy of multigroup cross-sections has a significant impact on shielding calculation. Challenges have arisen in generating accurate multigroup macroscopic cross-sections for some problems using the widely used cross-section processing code TRANSX 2.15. We developed the multigroup neutron-photon macroscopic cross-section processing module in the shielding transport code ARES. The module is capable of handling the neutron-photon coupled master libraries in MATXS format and providing the problem-dependent multigroup macroscopic cross-sections tailored to each specific shielding physics problem. The self-designed problems with a single nuclide, as well as the iron and OKTAVIAN experiments, are used to verify and analyze the accuracy of neutron and photon macroscopic cross-sections. Results indicate that the macroscopic cross-sections, neutron flux and neutron-photon leakage spectrum obtained by the MGMXS module are consistent with corresponding reference values. As for the JANUS Phase I fixed source shielding benchmark, the relative differences in the reaction rate between the calculation results and experimental data are within 20%. The module provides better problem-dependent multigroup macroscopic cross-sections for neutron and photon shielding calculations that satisfy the accuracy requirements of engineering applications. [ABSTRACT FROM AUTHOR]